Sample records for diverse fields ranging

  1. Socially-Oriented Ventures and Traditional Entrepreneurship Education Models: A Case Review

    ERIC Educational Resources Information Center

    Mars, Matthew M.; Garrison, Sharon

    2009-01-01

    As an academic area of study, entrepreneurship has become institutionalized and now includes students from a diverse range of disciplinary fields (M. M. Mars, 2006, 2007). Consequently, students' range of entrepreneurial interests has also become more diverse in scope and nature. Specifically, more students studying entrepreneurship are expressing…

  2. Conceptualizing and Communicating SoTL: A Framework for the Field

    ERIC Educational Resources Information Center

    Miller-Young, Janice; Yeo, Michelle

    2015-01-01

    The emerging field of SoTL is an inherently interdisciplinary endeavor which requires embracing a diverse range of research methods and disciplinary differences in world views. This diversity has caused a lack of coherence in its conceptualization and communication, which can be confusing for new scholars. Ongoing debates in the community concern…

  3. Diversity in Information Technology Education: Issues and Controversies

    ERIC Educational Resources Information Center

    Trajkovski, Goran, Ed.

    2006-01-01

    "Diversity in Information Technology Education: Issues and Controversies" sheds light on the status of diversity in the field of IT education. It identifies a wide range of problems that educators face on a daily basis, and gives practical, applicable solutions, mainly by showcasing successful and replicable examples. The chapters in "Diversity in…

  4. Increasing Diversity in School Psychology: Uniting the Efforts of Institutions, Faculty, Students, and Practitioners

    ERIC Educational Resources Information Center

    Grapin, Sally L.; Bocanegra, Joel O.; Green, Tonika Duren; Lee, Erica T.; Jaafar, Dounia

    2016-01-01

    Historically, practitioners from culturally diverse backgrounds, especially racial, ethnic, and linguistic (REL) minority backgrounds, have been significantly underrepresented in the field of school psychology. A lack of diversity in the workforce is problematic for a number of reasons and ultimately limits the range of talents, ideas, and…

  5. Global assessment of nitrogen deposition effects on terrestrial plant diversity: a synthesis

    Treesearch

    R. Bobbink; K. Hicks; J. Galloway; T. Spranger; R. Alkemade; M. Ashmore; M. Bustamante; S. Cinderby; E. Davidson; F. Dentener; B. Emmett; J.-W. Erisman; M. Fenn; F. Gilliam; A. Nordin; L. Pardo; W. De Vries

    2010-01-01

    Atmospheric nitrogen (N) deposition is a recognized threat to plant diversity in temperate and northern parts of Europe and North America. This paper assesses evidence from field experiments for N deposition effects and thresholds for terrestrial plant diversity protection across a latitudinal range of main categories of ecosystems, from arctic and boreal systems to...

  6. Genetic diversity of red-grained rice landraces in Hani's terraced fields based on phenotypic characteristics

    NASA Astrophysics Data System (ADS)

    Zhou, Xiaomei; Zheng, Yun; Zhang, Tingting; Zhang, Xiaoqian; Ma, Mengli; Meng, Hengling; Wang, Tiantao; Lu, Bingyue

    2018-06-01

    In order to provide useful information for protection and utilization of red-grained rice landraces from Hani's terraced fields, the phenotypic diversity of 61 red-grained rice landraces were assessed based 20 quantitative traits. The results indicated that the phenotypic diversity was abundant in red-grained rice landraces. Coefficients of variation (CV) ranged from 4.878% to 72.878%, and the largest of CV was the panicle neck length, while grain width was smallest. Shannon-Weaver diversity index (H') of 20 traits ranged from 1.464 to 2.165, the largest and the smallest H' values were observed in filled grain number and chalkiness, respectively. Cluster analysis based on unweighted pair group method showed 61 red-grain rice landraces grouped into eight clusters at a cut-off value of 6.2631. The first cluster included 11 landraces, the main cluster II involved 42 landraces, and the cluster IV included 3 landraces. Laopinzhonghongmi, Chena2, Laojingnuo, Bianhao6 and Baimi were separated from the main clusters.

  7. Handbook of Moral Development

    ERIC Educational Resources Information Center

    Killen, Melanie; Smetana, Judith

    2006-01-01

    The psychological study of moral development has expanded greatly, both in terms of the diversity of theoretical perspectives that are represented in the field, as well as in the range of topics that have been studied. This "Handbook of Moral Development" represents the diversity and multidisciplinary influences on current theorizing about the…

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Novotny, Lukas

    The seventh conference in the NFO conference series, held here in Rochester, provided to be the principal forum for advances in sub-wavelength optics, near-field optical microscopy, local field enhancement, instrumental developments and the ever-increasing range of applications. This conference brought together the diverse scientific communities working on the theory and application of near-field optics (NFO) and related techniques.

  9. Selection and Participation in Higher Education: University Selection in Support of Student Success and Diversity of Participation

    ERIC Educational Resources Information Center

    Palmer, Nigel; Bexley, Emmaline; James, Richard

    2011-01-01

    A range of imperatives underpin university selection practices. These include demonstrating merit based on prior academic achievement and supporting successful graduate outcomes in the professions and in broader fields of endeavour. They also include improving diversity of participation and equality of educational opportunity. Selection for…

  10. Correlating Species and Spectral Diversity using Remote Sensing in Successional Fields in Virginia

    NASA Astrophysics Data System (ADS)

    Aneece, I.; Epstein, H. E.

    2015-12-01

    Conserving biodiversity can help preserve ecosystem properties and function. As the increasing prevalence of invasive plant species threatens biodiversity, advances in remote sensing technology can help monitor invasive species and their effects on ecosystems and plant communities. To assess whether we could study the effects of invasive species on biodiversity using remote sensing, we asked whether species diversity was positively correlated with spectral diversity, and whether correlations differed among spectral regions along the visible and near-infrared range. To answer these questions, we established community plots in secondary successional fields at the Blandy Experimental Farm in northern Virginia and collected vegetation surveys and ground-level hyperspectral data from 350 to 1025 nm wavelengths. Pearson correlation analysis revealed a positive correlation between spectral diversity and species diversity in the visible ranges of 350-499 nm (Pearson correlation=0.69, p=0.01), 500-589 nm (Pearson=0.64, p=0.03), and 590-674 nm (Pearson=0.70, p=0.01), slight positive correlation in the red edge range of 675-754 nm (Pearson=0.56, p=0.06), and no correlation in the near-infrared ranges of 755-924 nm (Pearson=-0.06, p=0.85) and 925-1025 nm (Pearson=0.30, p=0.34). These differences in correlations across spectral regions may be due to the elements that contribute to signatures in those regions and spectral data transformation methods. To investigate the role of pigment variability in these correlations, we estimated chlorophyll, carotenoid, and anthocyanin concentrations of five dominant species in the plots using vegetation indices. Although interspecific variability in pigment levels exceeded intraspecific variability, chlorophyll (F value=118) was more varied within species than carotenoids (F=322) and anthocyanins (F=126), perhaps contributing to the lack of correlation between species diversity and spectral diversity in the red edge region. Interspecific differences in pigment levels, however, make it possible to differentiate species remotely.

  11. Australian Applied Linguistics in Relation to International Trends

    ERIC Educational Resources Information Center

    Baldauf, Richard B., Jr.; Kaplan, Robert B.

    2010-01-01

    Applied Linguistics is a diverse field, comprising a substantial number of sub-fields, sub-specialisations and related fields. To see that this is the case one need only examine the various handbooks and encyclopaedic references that have been published in the last ten years to see the wide range of topics that have been covered. As with many…

  12. Bridging the Gender Gap: The demographics of scientists in the USDA Forest Service and academia

    Treesearch

    Christel C. Kern; Laura S. Kenefic; Susan L. Stout

    2015-01-01

    Past research has established that diverse scientific communities foster innovation and problem solving more effectively than communities with a narrow range of knowledge, skills, and experience. However, gender diversity among scientists is limited, particularly in natural-resource fields. We compared data on scientist gender and rank from the US Department of...

  13. Association mapping analysis of the response to Macrophomina phaseolina in the Andean Diversity Panel

    USDA-ARS?s Scientific Manuscript database

    The Andean Diversity Panel was evaluated for response to inoculation with charcoal rot in a field trial in Isabela, Puerto Rico in 2012. The trial was inoculated with backpack sprayers at flowering and a visual evaluation was conducted three weeks later. There was a broad range of response, with abo...

  14. Molecular diversity of arbuscular mycorrhizal fungi in onion roots from organic and conventional farming systems in the Netherlands.

    PubMed

    Galván, Guillermo A; Parádi, István; Burger, Karin; Baar, Jacqueline; Kuyper, Thomas W; Scholten, Olga E; Kik, Chris

    2009-06-01

    Diversity and colonization levels of naturally occurring arbuscular mycorrhizal fungi (AMF) in onion roots were studied to compare organic and conventional farming systems in the Netherlands. In 2004, 20 onion fields were sampled in a balanced survey between farming systems and between two regions, namely, Zeeland and Flevoland. In 2005, nine conventional and ten organic fields were additionally surveyed in Flevoland. AMF phylotypes were identified by rDNA sequencing. All plants were colonized, with 60% for arbuscular colonization and 84% for hyphal colonization as grand means. In Zeeland, onion roots from organic fields had higher fractional colonization levels than those from conventional fields. Onion yields in conventional farming were positively correlated with colonization level. Overall, 14 AMF phylotypes were identified. The number of phylotypes per field ranged from one to six. Two phylotypes associated with the Glomus mosseae-coronatum and the G. caledonium-geosporum species complexes were the most abundant, whereas other phylotypes were infrequently found. Organic and conventional farming systems had similar number of phylotypes per field and Shannon diversity indices. A few organic and conventional fields had larger number of phylotypes, including phylotypes associated with the genera Glomus-B, Archaeospora, and Paraglomus. This suggests that farming systems as such did not influence AMF diversity, but rather specific environmental conditions or agricultural practices.

  15. A general framework for analysing diversity in science, technology and society.

    PubMed

    Stirling, Andy

    2007-08-22

    This paper addresses the scope for more integrated general analysis of diversity in science, technology and society. It proposes a framework recognizing three necessary but individually insufficient properties of diversity. Based on 10 quality criteria, it suggests a general quantitative non-parametric diversity heuristic. This allows the systematic exploration of diversity under different perspectives, including divergent conceptions of relevant attributes and contrasting weightings on different diversity properties. It is shown how this heuristic may be used to explore different possible trade-offs between diversity and other aspects of interest, including portfolio interactions. The resulting approach offers a way to be more systematic and transparent in the treatment of scientific and technological diversity in a range of fields, including conservation management, research governance, energy policy and sustainable innovation.

  16. Topographic influences on vegetation mosaics and tree diversity in the Chihuahuan Desert Borderlands.

    PubMed

    Poulos, Helen M; Camp, Ann E

    2010-04-01

    The abundance and distribution of species reflect how the niche requirements of species and the dynamics of populations interact with spatial and temporal variation in the environment. This study investigated the influence of geographical variation in environmental site conditions on tree dominance and diversity patterns in three topographically dissected mountain ranges in west Texas, USA, and northern Mexico. We measured tree abundance and basal area using a systematic sampling design across the forested areas of three mountain ranges and related these data to a suite of environmental parameters derived from field and digital elevation model data. We employed cluster analysis, classification and regression trees (CART), and rarefaction to identify (1) the dominant forest cover types across the three study sites and (2) environmental influences on tree distribution and diversity patterns. Elevation, topographic position, and incident solar radiation were the major influences on tree dominance and diversity. Mesic valley bottoms hosted high-diversity vegetation types, while hotter and drier mid-slopes and ridgetops supported lower tree diversity. Valley bottoms and other topographic positions shared few species, indicating high species turnover at the landscape scale. Mountain ranges with high topographic complexity also had higher species richness, suggesting that geographical variability in environmental conditions was a major influence on tree diversity. This study stressed the importance of landscape- and regional-scale topographic variability as a key factor controlling vegetation pattern and diversity in southwestern North America.

  17. Securing Information Technology in Healthcare

    PubMed Central

    Anthony, Denise; Campbell, Andrew T.; Candon, Thomas; Gettinger, Andrew; Kotz, David; Marsch, Lisa A.; Molina-Markham, Andrés; Page, Karen; Smith, Sean W.; Gunter, Carl A.; Johnson, M. Eric

    2014-01-01

    Dartmouth College’s Institute for Security, Technology, and Society conducted three workshops on securing information technology in healthcare, attended by a diverse range of experts in the field. This article summarizes the three workshops. PMID:25379030

  18. Evidence for a common scale O(0.1) m that controls seabed scattering and reverberation in shallow water.

    PubMed

    Holland, Charles W

    2012-10-01

    Analysis of the spectral content of long-range reverberation yields two observations. First, there is a remarkably similar scale, O(0.1) m, between three diverse continental shelf regions. This is surprising given the complexity and diversity of geologic processes. Second, there is strong evidence that the scale is associated with heterogeneities within the sediment. Thus, sediment volume scattering, not interface scattering, controls long-range reverberation from a few hundred hertz to several kilohertz. This is also unexpected given that at long ranges the vertical grazing angles are less than the critical angle, and hence the penetration of the acoustic field into the sub-bottom is expected to be modest. The consistency of the scale, O(0.1) m, suggests an underlying feature or mechanism that is consistent across many ostensibly diverse geological settings. Neither the feature nor mechanism is known at this time.

  19. Phylogeography of infectious haematopoietic necrosis virus in North America

    USGS Publications Warehouse

    Kurath, Gael; Garver, Kyle A.; Troyer, Ryan M.; Emmenegger, Eveline J.; Einer-Jensen, Katja; Anderson, Eric D.

    2003-01-01

    Infectious hematopoietic necrosis virus (IHNV) is a rhabdoviral pathogen that infects wild and cultured salmonid fish throughout the Pacific Northwest of North America. IHNV causes severe epidemics in young fish and can cause disease or occur asymptomatically in adults. In a broad survey of 323 IHNV field isolates, sequence analysis of a 303 nucleotide variable region within the glycoprotein gene revealed a maximum nucleotide diversity of 8.6 %, indicating low genetic diversity overall for this virus. Phylogenetic analysis revealed three major virus genogroups, designated U, M and L, which varied in topography and geographical range. Intragenogroup genetic diversity measures indicated that the M genogroup had three- to fourfold more diversity than the other genogroups and suggested relatively rapid evolution of the M genogroup and stasis within the U genogroup. We speculate that factors influencing IHNV evolution may have included ocean migration ranges of their salmonid host populations and anthropogenic effects associated with fish culture.

  20. Chemical and behavioral studies of femoral gland secretions in iguanid lizards.

    PubMed

    Alberts, A C

    1993-01-01

    Comparative studies on the chemistry and behavioral significance of femoral gland secretions in desert iguanas (Dipsosaurus dorsalis) and green iguanas (Iguana iguana) are reviewed. Field and laboratory studies suggest that femoral gland secretions function in conspecific recognition and range marking. In desert iguanas, secretions are of low volatility and may be detected initially using long-range ultraviolet visual cues. In contrast, green iguana secretions contain a diversity of volatile lipids and appear to be localized by chemoreception. Interspecific differences in femoral gland chemistry may reflect adaptations to the diverse climatic conditions of arid desert and tropical forest environments.

  1. The Spark of Disruptive Innovation for Space Physics and Aeronomy

    NASA Astrophysics Data System (ADS)

    MacDonald, E.

    2017-12-01

    What is disruptive innovation and why does it matter for Space Physics and Aeronomy (SPA)? This presentation will define disruptive innovation and present several examples relevant to SPA. These examples range from Cubesats to Citizen Science. Disruptive innovation requires not just an idea but also execution. Why do we need disruptive innovation? Simply put, we need to break out of our comfortable rut to solve bigger problems and evolve as a field for the future. These opportunities are exciting and they are difficult. SPA is well-suited to these types of interdisciplinary applications, due to its dual fundamental and applied nature that dovetails with many other fields. Challenges are that we do not incentivize disruptive innovation, we do not recognize it, and we typically do not fund it. As a result we are risk averse and we suffer from the "Matthew effect" of accumulated advantage. We do not allow ourselves to learn from new and uncomfortable angles and recognize the innovation that comes from there. The strength of having a more diverse and inclusive field is that a range of more diverse ideas and perspectives will be promoted. The next big innovations for SPA may come from the outside, and the best way to capture such ideas may be to promote diversity and inclusion at all levels.

  2. Curriculum Documents and Practice in the NZ Polytechnic Sector: Consensus and Dissensus

    ERIC Educational Resources Information Center

    Melles, Gavin

    2008-01-01

    In New Zealand the polytechnic sector embraces a range of post-compulsory education fields. Fields as diverse as nursing, business, social work and English as a Second Language (ESL) may co-exist on polytechnic campuses and are subject to similar curriculum documentation processes. The common competency-based framework and discourse of such…

  3. Ethnography for Teachers' Professional Development: Japanese Approach of Investigation on Classroom Activities

    ERIC Educational Resources Information Center

    Matoba, Masami; Sarkar Arani Mohammed Reza

    2006-01-01

    In this paper, we examine how journal and ethnography field notes in Jugyou Kenkyu (lesson study) help teachers to understand the diverse range of talents and abilities of their students. Especially, we focus on how ethnography field note and reflective papers (karate) help teachers to change their assumptions about student learning. The data…

  4. Geochemistry and origin of regional dolomites

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanson, G.N.; Meyers, W.J.

    1992-01-01

    This grant supports research on the origins and geochemical aspects of regional dolomites. Eight graduate students are involved in research on dolomite allowing a diverse range of studies. This report outlines their work in the field. (JL)

  5. The Training of Epidemiologists and Diversity in Epidemiology: Findings from the 2006 Congress of Epidemiology Survey

    PubMed Central

    Carter-Pokras, Olivia D.; Spirtas, Robert; Bethune, Lisa; Mays, Vickie; Freeman, Vincent L.; Cozier, Yvette C.

    2013-01-01

    Purpose In the past decade, we have witnessed increasing numbers of individuals entering the field of epidemiology. With the increase also has come a diversity of training and paths by which individuals entered the field. The purpose of this survey was characterization of the epidemiology workforce, its job diversity, and continuing education needs. Methods The Minority Affairs and Membership committees of the American College of Epidemiology (ACE) prepared and administered a workforce survey to identify racial/ethnic diversity, demographic background, workplace type, credentials, income, subspecialties, and continuing education needs of epidemiologists. The survey was self-administered to attendees of the Second North American Congress of Epidemiology in June 2006. Results A sample of 397 respondents of the 1348 registered for the Congress was captured (29.5% response). Epidemiologists who participated were from 36 states and 18 countries; 54.6% were trained at the doctoral level; 19.1% earned $120,001 or more a year. A wide range of epidemiology subspecialties and continuing education needs were identified. Conclusions This preliminary snapshot of epidemiologists indicates a wide range of training mechanisms, workplace sites, and subspecialties. Results indicate a need for examination of the core graduate training needs of epidemiologist as well as responding to desired professional development needs through the provision of continuing educations efforts. PMID:19344867

  6. On the diversity of compact objects within supernova remnants - I. A parametric model for magnetic field evolution

    NASA Astrophysics Data System (ADS)

    Rogers, Adam; Safi-Harb, Samar

    2016-04-01

    A wealth of X-ray and radio observations has revealed in the past decade a growing diversity of neutron stars (NSs) with properties spanning orders of magnitude in magnetic field strength and ages, and with emission processes explained by a range of mechanisms dictating their radiation properties. However, serious difficulties exist with the magneto-dipole model of isolated NS fields and their inferred ages, such as a large range of observed braking indices (n, with values often <3) and a mismatch between the NS and associated supernova remnant (SNR) ages. This problem arises primarily from the assumptions of a constant magnetic field with n = 3, and an initial spin period that is much smaller than the observed current period. It has been suggested that a solution to this problem involves magnetic field evolution, with some NSs having magnetic fields buried within the crust by accretion of fall-back supernova material following their birth. In this work, we explore a parametric phenomenological model for magnetic field growth that generalizes previous suggested field evolution functions, and apply it to a variety of NSs with both secure SNR associations and known ages. We explore the flexibility of the model by recovering the results of previous work on buried magnetic fields in young NSs. Our model fits suggest that apparently disparate classes of NSs may be related to one another through the time evolution of the magnetic field.

  7. State of the Field: A Critical Essay on the 2003 Comparative Education Review Bibliography

    ERIC Educational Resources Information Center

    Raby, Rosalind Latiner

    2004-01-01

    The Comparative Education Review bibliography compiles articles from a diverse selection of journals on a broad range of themes and subject areas that are of particular interest to CER readers. In particular, the CER bibliography helps to broaden the field of pertinent articles that may be overlooked when doing a simple search. The journals…

  8. Optoelectrofluidic field separation based on light-intensity gradients

    PubMed Central

    Lee, Sanghyun; Park, Hyun Jin; Yoon, Jin Sung; Kang, Kwan Hyoung

    2010-01-01

    Optoelectrofluidic field separation (OEFS) of particles under light -intensity gradient (LIG) is reported, where the LIG illumination on the photoconductive layer converts the short-ranged dielectrophoresis (DEP) force to the long-ranged one. The long-ranged DEP force can compete with the hydrodynamic force by alternating current electro-osmosis (ACEO) over the entire illumination area for realizing effective field separation of particles. In the OEFS system, the codirectional illumination and observation induce the levitation effect, compensating the attenuation of the DEP force under LIG illumination by slightly floating particles from the surface. Results of the field separation and concentration of diverse particle pairs (0.82–16 μm) are well demonstrated, and conditions determining the critical radius and effective particle manipulation are discussed. The OEFS with codirectional LIG strategy could be a promising particle manipulation method in many applications where a rapid manipulation of biological cells and particles over the entire working area are of interest. PMID:20697461

  9. Optoelectrofluidic field separation based on light-intensity gradients.

    PubMed

    Lee, Sanghyun; Park, Hyun Jin; Yoon, Jin Sung; Kang, Kwan Hyoung

    2010-07-14

    Optoelectrofluidic field separation (OEFS) of particles under light -intensity gradient (LIG) is reported, where the LIG illumination on the photoconductive layer converts the short-ranged dielectrophoresis (DEP) force to the long-ranged one. The long-ranged DEP force can compete with the hydrodynamic force by alternating current electro-osmosis (ACEO) over the entire illumination area for realizing effective field separation of particles. In the OEFS system, the codirectional illumination and observation induce the levitation effect, compensating the attenuation of the DEP force under LIG illumination by slightly floating particles from the surface. Results of the field separation and concentration of diverse particle pairs (0.82-16 mum) are well demonstrated, and conditions determining the critical radius and effective particle manipulation are discussed. The OEFS with codirectional LIG strategy could be a promising particle manipulation method in many applications where a rapid manipulation of biological cells and particles over the entire working area are of interest.

  10. Near Field Observations of Seismicity in Volcanic Environments: A Read-Made Field Laboratory

    NASA Astrophysics Data System (ADS)

    Bean, C. J.; Thun, J.; Eibl, E. P. S.; Benson, P. M.; Rowley, P.; Lokmer, I.; Cauchie, L.

    2017-12-01

    Volcanic environments experience periods of rapid stress fluctuations and consequent seismicity. This volcano seismicity is diverse in character, spanning the range from discrete high frequency events through low-frequency earthquakes and tremor. The inter-relationships between these events appear to be controlled by edifice rheology, stress state and the presence of fluids (which help modulate the stress field). In general volcanoes are accessible to instrumentation, allowing near-field access to the seismicity at play. Here we present results from a range of field, numerical and laboratory experiments that demonstrate the controls that rheology and strain rate play on seismicity type. In particular we demonstrate the role played by internal friction angles on the initiation and evolution of seismicity, in dry weak-compliant volcanic materials. Furthermore we show the importance of near field observation in constraining details of the seismic source, in a meso-scale field setting.

  11. Field-based evaluations of horizontal flat-plate fish screens

    USGS Publications Warehouse

    Rose, B.P.; Mesa, M.G.; Barbin-Zydlewski, G.

    2008-01-01

    Diversions from streams are often screened to prevent the loss of or injury to fish. Hydraulic criteria meant to protect fish that encounter screens have been developed, but primarily for screens that are vertical to the water flow rather than horizontal. For this reason, we measured selected hydraulic variables and released wild rainbow trout Oncorhynchus mykiss over two types of horizontal flat-plate fish screens in the field. Our goal was to assess the efficacy of these screens under a variety of conditions in the field and provide information that could be used to develop criteria for safe fish passage. We evaluated three different invertedweir screens over a range of stream (0.24-1.77 m3/s) and diversion flows (0.10-0.31 m3/s). Approach velocities (AVs) ranged from 3 to 8 cm/s and sweeping velocities (SVs) from 69 to 143 cm/s. We also evaluated a simple backwatered screen over stream flows of 0.23-0.79 m3/s and diversion flows of 0.08-0.32 m3/s. The mean SVs for this screen ranged from 15 to 66 cm/s and the mean AVs from 1 to 5 cm/s. The survival rates of fish held for 24 h after passage over these screens exceeded 98%. Overall, the number of fish-screen contacts was low and the injuries related to passage were infrequent and consisted primarily of minor fin injuries. Our results indicate that screens of this type have great potential as safe and effective fish screens for small diversions. Care must be taken, however, to avoid operating conditions that produce shallow or no water over the screen surface, situations of high AVs and low SVs at backwatered screens, and situations producing a localized high AV with spiraling flow. ?? Copyright by the American Fisheries Society 2008.

  12. A Serpentinite-Hosted Ecosystem: The Lost City Hydrothermal Field

    NASA Astrophysics Data System (ADS)

    Kelley, Deborah S.; Karson, Jeffrey A.; Früh-Green, Gretchen L.; Yoerger, Dana R.; Shank, Timothy M.; Butterfield, David A.; Hayes, John M.; Schrenk, Matthew O.; Olson, Eric J.; Proskurowski, Giora; Jakuba, Mike; Bradley, Al; Larson, Ben; Ludwig, Kristin; Glickson, Deborah; Buckman, Kate; Bradley, Alexander S.; Brazelton, William J.; Roe, Kevin; Elend, Mitch J.; Delacour, Adélie; Bernasconi, Stefano M.; Lilley, Marvin D.; Baross, John A.; Summons, Roger E.; Sylva, Sean P.

    2005-03-01

    The serpentinite-hosted Lost City hydrothermal field is a remarkable submarine ecosystem in which geological, chemical, and biological processes are intimately interlinked. Reactions between seawater and upper mantle peridotite produce methane- and hydrogen-rich fluids, with temperatures ranging from <40° to 90°C at pH 9 to 11, and carbonate chimneys 30 to 60 meters tall. A low diversity of microorganisms related to methane-cycling Archaea thrive in the warm porous interiors of the edifices. Macrofaunal communities show a degree of species diversity at least as high as that of black smoker vent sites along the Mid-Atlantic Ridge, but they lack the high biomasses of chemosynthetic organisms that are typical of volcanically driven systems.

  13. Synthetic biology: advancing the design of diverse genetic systems

    PubMed Central

    Wang, Yen-Hsiang; Wei, Kathy Y.; Smolke, Christina D.

    2013-01-01

    A main objective of synthetic biology is to make the process of designing genetically-encoded biological systems more systematic, predictable, robust, scalable, and efficient. The examples of genetic systems in the field vary widely in terms of operating hosts, compositional approaches, and network complexity, ranging from a simple genetic switch to search-and-destroy systems. While significant advances in synthesis capabilities support the potential for the implementation of pathway- and genome-scale programs, several design challenges currently restrict the scale of systems that can be reasonably designed and implemented. Synthetic biology offers much promise in developing systems to address challenges faced in manufacturing, the environment and sustainability, and health and medicine, but the realization of this potential is currently limited by the diversity of available parts and effective design frameworks. As researchers make progress in bridging this design gap, advances in the field hint at ever more diverse applications for biological systems. PMID:23413816

  14. SemanticOrganizer: A Customizable Semantic Repository for Distributed NASA Project Teams

    NASA Technical Reports Server (NTRS)

    Keller, Richard M.; Berrios, Daniel C.; Carvalho, Robert E.; Hall, David R.; Rich, Stephen J.; Sturken, Ian B.; Swanson, Keith J.; Wolfe, Shawn R.

    2004-01-01

    SemanticOrganizer is a collaborative knowledge management system designed to support distributed NASA projects, including diverse teams of scientists, engineers, and accident investigators. The system provides a customizable, semantically structured information repository that stores work products relevant to multiple projects of differing types. SemanticOrganizer is one of the earliest and largest semantic web applications deployed at NASA to date, and has been used in diverse contexts ranging from the investigation of Space Shuttle Columbia's accident to the search for life on other planets. Although the underlying repository employs a single unified ontology, access control and ontology customization mechanisms make the repository contents appear different for each project team. This paper describes SemanticOrganizer, its customization facilities, and a sampling of its applications. The paper also summarizes some key lessons learned from building and fielding a successful semantic web application across a wide-ranging set of domains with diverse users.

  15. A 40-kW fuel cell field test summary utilities activities report

    NASA Astrophysics Data System (ADS)

    Racine, W. C.; Londos, T. C.

    1987-07-01

    Forty six 40 kW fuel cell power plants were field tested by 37 host participants at 42 sites in a variety of commercial, light industrial and multifamily residential applications. The participants obtained over 300,000 hours of operating experience with the power plants covering a diverse range of applications for power plant electricity and heat utilization in both single and multiple unit installations.

  16. APA Educational Psychology Handbook

    ERIC Educational Resources Information Center

    Harris, Karen R., Ed.; Graham, Steve, Ed.; Urdan, Tim, Ed.

    2011-01-01

    The "APA Educational Psychology Handbook" reflects the broad nature of the field today, with state-of-the-science reviews of the diverse critical theories driving research and practice; in-depth investigation of the range of individual differences and cultural/contextual factors that affect student achievement, motivation, and beliefs;…

  17. Geochemistry and origin of regional dolomites. Technical progress report, July 26, 1991--April 21, 1992

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanson, G.N.; Meyers, W.J.

    1992-07-01

    This grant supports research on the origins and geochemical aspects of regional dolomites. Eight graduate students are involved in research on dolomite allowing a diverse range of studies. This report outlines their work in the field. (JL)

  18. Pop Goes the Culture

    ERIC Educational Resources Information Center

    Kurlansky, Mark J.

    1977-01-01

    Popular culture is defended as a solid academic entry that is a new approach to sociology, art, and literature. The contributions and theories of three professors are discussed: Arthur Asa Berger, Leslie Fiedler, and Alan Gowans. They illustrate the range and diversity in the pop culture field. (LBH)

  19. Does Interdisciplinary Research Lead to Higher Citation Impact? The Different Effect of Proximal and Distal Interdisciplinarity

    PubMed Central

    Yegros-Yegros, Alfredo; Rafols, Ismael; D’Este, Pablo

    2015-01-01

    This article analyses the effect of degree of interdisciplinarity on the citation impact of individual publications for four different scientific fields. We operationalise interdisciplinarity as disciplinary diversity in the references of a publication, and rather than treating interdisciplinarity as a monodimensional property, we investigate the separate effect of different aspects of diversity on citation impact: i.e. variety, balance and disparity. We use a Tobit regression model to examine the effect of these properties of interdisciplinarity on citation impact, controlling for a range of variables associated with the characteristics of publications. We find that variety has a positive effect on impact, whereas balance and disparity have a negative effect. Our results further qualify the separate effect of these three aspects of diversity by pointing out that all three dimensions of interdisciplinarity display a curvilinear (inverted U-shape) relationship with citation impact. These findings can be interpreted in two different ways. On the one hand, they are consistent with the view that, while combining multiple fields has a positive effect in knowledge creation, successful research is better achieved through research efforts that draw on a relatively proximal range of fields, as distal interdisciplinary research might be too risky and more likely to fail. On the other hand, these results may be interpreted as suggesting that scientific audiences are reluctant to cite heterodox papers that mix highly disparate bodies of knowledge—thus giving less credit to publications that are too groundbreaking or challenging. PMID:26266805

  20. Does Interdisciplinary Research Lead to Higher Citation Impact? The Different Effect of Proximal and Distal Interdisciplinarity.

    PubMed

    Yegros-Yegros, Alfredo; Rafols, Ismael; D'Este, Pablo

    2015-01-01

    This article analyses the effect of degree of interdisciplinarity on the citation impact of individual publications for four different scientific fields. We operationalise interdisciplinarity as disciplinary diversity in the references of a publication, and rather than treating interdisciplinarity as a monodimensional property, we investigate the separate effect of different aspects of diversity on citation impact: i.e. variety, balance and disparity. We use a Tobit regression model to examine the effect of these properties of interdisciplinarity on citation impact, controlling for a range of variables associated with the characteristics of publications. We find that variety has a positive effect on impact, whereas balance and disparity have a negative effect. Our results further qualify the separate effect of these three aspects of diversity by pointing out that all three dimensions of interdisciplinarity display a curvilinear (inverted U-shape) relationship with citation impact. These findings can be interpreted in two different ways. On the one hand, they are consistent with the view that, while combining multiple fields has a positive effect in knowledge creation, successful research is better achieved through research efforts that draw on a relatively proximal range of fields, as distal interdisciplinary research might be too risky and more likely to fail. On the other hand, these results may be interpreted as suggesting that scientific audiences are reluctant to cite heterodox papers that mix highly disparate bodies of knowledge--thus giving less credit to publications that are too groundbreaking or challenging.

  1. The properties and origin of magnetic fields in white dwarfs

    NASA Astrophysics Data System (ADS)

    Kawka, A.

    2018-01-01

    A significant fraction of white dwarfs harbour a magnetic field with strengths ranging from a few kG up to about 1000 MG. The fraction appears to depend on the specific class of white dwarfs being investigated and may hold some clues to the origin of their magnetic field. The number of white dwarfs with variable fields as a function of their rotation phase have revealed a large field structure diversity, from a simple offset dipole to structures with spots or multipoles. A review of the current challenges in modelling white dwarf atmospheres in the presence of a magnetic field is presented, and the proposed scenarios for the formation of magnetic fields in white dwarfs are examined.

  2. Novel detection schemes of nuclear magnetic resonance and magnetic resonance imaging: applications from analytical chemistry to molecular sensors.

    PubMed

    Harel, Elad; Schröder, Leif; Xu, Shoujun

    2008-01-01

    Nuclear magnetic resonance (NMR) is a well-established analytical technique in chemistry. The ability to precisely control the nuclear spin interactions that give rise to the NMR phenomenon has led to revolutionary advances in fields as diverse as protein structure determination and medical diagnosis. Here, we discuss methods for increasing the sensitivity of magnetic resonance experiments, moving away from the paradigm of traditional NMR by separating the encoding and detection steps of the experiment. This added flexibility allows for diverse applications ranging from lab-on-a-chip flow imaging and biological sensors to optical detection of magnetic resonance imaging at low magnetic fields. We aim to compare and discuss various approaches for a host of problems in material science, biology, and physics that differ from the high-field methods routinely used in analytical chemistry and medical imaging.

  3. Magnetic maps in animals: nature's GPS.

    PubMed

    Lohmann, Kenneth J; Lohmann, Catherine M F; Putman, Nathan F

    2007-11-01

    Diverse animals detect the Earth's magnetic field and use it as a cue in orientation and navigation. Most research on magnetoreception has focused on the directional or ;compass' information that can be extracted from the Earth's field. Because the field varies predictably across the surface of the globe, however, it also provides a potential source of positional or 'map' information, which some animals use to steer themselves along migratory pathways or to navigate toward specific target areas. The use of magnetic positional information has been demonstrated in several diverse animals including sea turtles, spiny lobsters, newts and birds, suggesting that such systems are phylogenetically widespread and can function over a wide range of spatial scales. These ;magnetic maps' have not yet been fully characterized. They may be organized in several fundamentally different ways, some of which bear little resemblance to human maps, and they may also be used in conjunction with unconventional navigational strategies.

  4. Plant diversity and root traits benefit physical properties key to soil function in grasslands.

    PubMed

    Gould, Iain J; Quinton, John N; Weigelt, Alexandra; De Deyn, Gerlinde B; Bardgett, Richard D

    2016-09-01

    Plant diversity loss impairs ecosystem functioning, including important effects on soil. Most studies that have explored plant diversity effects belowground, however, have largely focused on biological processes. As such, our understanding of how plant diversity impacts the soil physical environment remains limited, despite the fundamental role soil physical structure plays in ensuring soil function and ecosystem service provision. Here, in both a glasshouse and a long-term field study, we show that high plant diversity in grassland systems increases soil aggregate stability, a vital structural property of soil, and that root traits play a major role in determining diversity effects. We also reveal that the presence of particular plant species within mixed communities affects an even wider range of soil physical processes, including hydrology and soil strength regimes. Our results indicate that alongside well-documented effects on ecosystem functioning, plant diversity and root traits also benefit essential soil physical properties. © 2016 The Authors Ecology Letters published by CNRS and John Wiley & Sons Ltd.

  5. Nurturing a growing field: Computers & Geosciences

    NASA Astrophysics Data System (ADS)

    Mariethoz, Gregoire; Pebesma, Edzer

    2017-10-01

    Computational issues are becoming increasingly critical for virtually all fields of geoscience. This includes the development of improved algorithms and models, strategies for implementing high-performance computing, or the management and visualization of the large datasets provided by an ever-growing number of environmental sensors. Such issues are central to scientific fields as diverse as geological modeling, Earth observation, geophysics or climatology, to name just a few. Related computational advances, across a range of geoscience disciplines, are the core focus of Computers & Geosciences, which is thus a truly multidisciplinary journal.

  6. Looking toward the Blue Sky: Environmental Education Researchers' Experience, Influences, and Aspirations

    ERIC Educational Resources Information Center

    Ardoin, Nicole M.; Clark, Charlotte R.; Wojcik, Deborah J.

    2016-01-01

    Environmental education (EE) researchers hail from diverse disciplines and sociocultural contexts, work in a range of settings, and envision various outcomes. Desiring to better understand their backgrounds, interests, and aspirations for the field, we surveyed EE researchers to explore their theoretical and educational influences and what they…

  7. IsoBank – Stable isotope ecology in the age of ‘Big Data’

    USDA-ARS?s Scientific Manuscript database

    Stable isotopes ratios provide valuable information to fish biologists working in a diverse range of fields: e.g. ecologists, population biologists and fishery managers. Ecologists take advantage of stable isotope ratios to provide information on the diet and migration history of consumers or when a...

  8. The Application of Peer Teaching in Digital Forensics Education

    ERIC Educational Resources Information Center

    Govan, Michelle

    2016-01-01

    The field of digital forensics requires a multidisciplinary understanding of a range of diverse subjects, but is interdisciplinary (in using principles, techniques and theories from other disciplines) encompassing both computer and forensic science. This requires that practitioners have a deep technical knowledge and understanding, but that they…

  9. Race, Identity and Representation in Education.

    ERIC Educational Resources Information Center

    McCarthy, Cameron, Ed.; Crichlow, Warren, Ed.

    This book presents 24 essays, written by scholars in the humanities and social sciences, that offer cultural and poststructural appraisals of race. The essays illustrate the range, scope, diversity, appeal, and power of work currently underway in the field. They attempt to intervene in the increasingly acrimonious debate over racial inequality and…

  10. Using Technology to Support STEM Reading

    ERIC Educational Resources Information Center

    Schneps, Matthew H.; O'Keeffe, Jamie K.; Heffner-Wong, Amanda; Sonnert, Gerhard

    2010-01-01

    Tasks in science, technology, engineering, and mathematics (STEM) are unusually varied because they target phenomena occurring in diverse domains and call upon a wide range of abilities to perform them. The fact that STEM tasks cover such a broad spectrum of abilities makes these fields uncharacteristically inclusive: Individuals with disabilities…

  11. Multiple stressor effects in relation to declining amphibian populations

    USGS Publications Warehouse

    Linder, Greg L.; Krest, Sherry K.; Sparling, Donald; Little, E.

    2003-01-01

    Original research discusses the protocols and approaches to studying the effects of multiple environmental stressors on amphibian populations and gives new perspectives on this complicated subject. This new publication integrates a variety of stressors that can act in concert and may ultimately cause a decline in amphibian populations.Sixteen peer-reviewed papers cover:Toxicity Assessment examines methods, which range from long-established laboratory approaches for evaluating adverse chemical effects to amphibians, to methods that link chemicals in surface waters, sediments, and soils with adverse effects observed among amphibians in the field.Field and Laboratory Studies illustrates studies in the evaluation of multiple stressor effects that may lead to declining amphibian populations. A range of laboratory and field studies of chemicals, such as herbicides, insecticides, chlorinated organic compounds, metals, and complex mixtures are also included.Causal Analysis demonstrates the range of tools currently available for evaluating "cause-effect" relationships between environmental stressors and declining amphibian populations.Audience: This new publication is a must-have for scientists and resource management professionals from diverse fields, including ecotoxicology, chemistry, ecology, field biology, conservation biology, and natural resource management.

  12. Soil and plant factors driving the community of soil-borne microorganisms across chronosequences of secondary succession of chalk grasslands with a neutral pH.

    PubMed

    Kuramae, Eiko; Gamper, Hannes; van Veen, Johannes; Kowalchuk, George

    2011-08-01

    Although soil pH has been shown to be an important factor driving microbial communities, relatively little is known about the other potentially important factors that shape soil-borne microbial community structure. This study examined plant and microbial communities across a series of neutral pH fields (pH=7.0-7.5) representing a chronosequence of secondary succession after former arable fields were taken out of production. These fields ranged from 17 to >66 years since the time of abandonment, and an adjacent arable field was included as a reference. Hierarchical clustering analysis, nonmetric multidimensional scaling and analysis of similarity of 52 different plant species showed that the plant community composition was significantly different in the different chronosequences, and that plant species richness and diversity increased with time since abandonment. The microbial community structure, as analyzed by phylogenetic microarrays (PhyloChips), was significantly different in arable field and the early succession stage, but no distinct microbial communities were observed for the intermediate and the late succession stages. The most determinant factors in shaping the soil-borne microbial communities were phosphorous and NH(4)(+). Plant community composition and diversity did not have a significant effect on the belowground microbial community structure or diversity. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  13. Progress and trends in complement therapeutics.

    PubMed

    Ricklin, Daniel; Lambris, John D

    2013-01-01

    The past few years have proven to be a highly successful and exciting period for the field of complement-directed drug discovery and development. Driven by promising experiences with the first marketed complement drugs, increased knowledge about the involvement of complement in health and disease, and improvements in structural and analytical techniques as well as animal models of disease, the field has seen a surge in creative approaches to therapeutically intervene at various stages of the cascade. An impressive panel of compounds that show promise in clinical trials is meanwhile being lined up in the pipelines of both small biotechnology and big pharmaceutical companies. Yet with this new focus on complement-targeted therapeutics, important questions concerning target selection, point and length of intervention, safety, and drug delivery emerge. In view of the diversity of the clinical disorders involving abnormal complement activity or regulation, which include both acute and chronic diseases and affect a wide range of organs, diverse yet specifically tailored therapeutic approaches may be needed to shift complement back into balance. This chapter highlights the key changes in the field that shape our current perception of complement-targeted drugs and provides a brief overview of recent strategies and emerging trends. Selected examples of complement-related diseases and inhibitor classes are highlighted to illustrate the diversity and creativity in field.

  14. Progress and Trends in Complement Therapeutics.

    PubMed

    Ricklin, Daniel; Lambris, John D

    2013-01-01

    The past few years have proven to be a highly successful and exciting period for the field of complement-directed drug discovery and development. Driven by promising experiences with the first marketed complement drugs, increased knowledge about the involvement of complement in health and disease, and improvements in structural and analytical techniques as well as animal models of disease, the field has seen a surge in creative approaches to therapeutically intervene at various stages of the cascade. An impressive panel of compounds that show promise in clinical trials is meanwhile being lined up in the pipelines of both small biotechnology and big pharmaceutical companies. Yet with this new focus on complement-targeted therapeutics, important questions concerning target selection, point and length of intervention, safety, and drug delivery emerge. In view of the diversity of the clinical disorders involving abnormal complement activity or regulation, which include both acute and chronic diseases and affect a wide range of organs, diverse yet specifically tailored therapeutic approaches may be needed to shift complement back into balance. This chapter highlights the key changes in the field that shape our current perception of complement-targeted drugs and provides a brief overview of recent strategies and emerging trends. Selected examples of complement-related diseases and inhibitor classes are highlighted to illustrate the diversity and creativity in field.

  15. Genetic diversity in three endangered pitcher plant species (Sarracenia; Sarraceniaceae) is lower than widespread congeners.

    PubMed

    Furches, M Steven; Small, Randall L; Furches, Anna

    2013-10-01

    Narrow-ranging, rare species often exhibit levels of genetic diversity lower than more common or widespread congeners. These taxa are at increased risk of extinction due to threats associated with natural as well as anthropogenic events. We assessed genetic variation in three federally endangered Sarracenia species. We discuss maintenance of genetic diversity and evolutionary implications of rarity. • We analyzed three noncoding chloroplast regions and nine microsatellite loci in populations spanning the geographic ranges of S. oreophila, S. alabamensis, and S. jonesii. The same microsatellite loci were used to examine a single field site of three more widespread species (S. alata, S. leucophylla, and S. rubra subsp. wherryi). • All three endangered species have experienced reductions in population size and numbers. All show considerably less variation than more widespread members of the genus. Sarracenia alabamensis maintains the greatest microsatellite variation but has the fewest remaining populations and may be under the greatest threat. More widespread S. oreophila maintains surprising chloroplast diversity, yet exhibits little microsatellite diversity. Sarracenia jonesii lacks chloroplast diversity, yet maintains greater microsatellite diversity than S. oreophila. • The three endangered species differ in levels and structure of diversity, yet not in predictable ways, emphasizing that unique demographic and ecological histories, rather than current distribution and population size, best explain present patterns of genetic variation. Maintenance of remaining genetic variation is important, but preventing further habitat loss and degradation is critical.

  16. Shallow seismicity in volcanic system: what role does the edifice play?

    NASA Astrophysics Data System (ADS)

    Bean, Chris; Lokmer, Ivan

    2017-04-01

    Seismicity in the upper two kilometres in volcanic systems is complex and very diverse in nature. The origins lie in the multi-physics nature of source processes and in the often extreme heterogeneity in near surface structure, which introduces strong seismic wave propagation path effects that often 'hide' the source itself. Other complicating factors are that we are often in the seismic near-field so waveforms can be intrinsically more complex than in far-field earthquake seismology. The traditional focus for an explanation of the diverse nature of shallow seismic signals is to call on the direct action of fluids in the system. Fits to model data are then used to elucidate properties of the plumbing system. Here we show that solutions based on these conceptual models are not unique and that models based on a diverse range of quasi-brittle failure of low stiffness near surface structures are equally valid from a data fit perspective. These earthquake-like sources also explain aspects of edifice deformation that are as yet poorly quantified.

  17. Assessing five field sampling methods to monitor Yellowstone National Park's northern ungulate winter range: the advantages and disadvantages of implementing a new sampling protocol

    Treesearch

    Pamela G. Sikkink; Roy Renkin; Geneva Chong; Art Sikkink

    2013-01-01

    The five field sampling methods tested for this study differed in richness and Simpson's Index values calculated from the raw data. How much the methods differed, and which ones were most similar to each other, depended on which diversity measure and which type of data were used for comparisons. When the number of species (richness) was used as a measure of...

  18. Mosquito vector diversity across habitats in central Thailand endemic for dengue and other arthropod-borne diseases.

    PubMed

    Thongsripong, Panpim; Green, Amy; Kittayapong, Pattamaporn; Kapan, Durrell; Wilcox, Bruce; Bennett, Shannon

    2013-01-01

    Recent years have seen the greatest ecological disturbances of our times, with global human expansion, species and habitat loss, climate change, and the emergence of new and previously-known infectious diseases. Biodiversity loss affects infectious disease risk by disrupting normal relationships between hosts and pathogens. Mosquito-borne pathogens respond to changing dynamics on multiple transmission levels and appear to increase in disturbed systems, yet current knowledge of mosquito diversity and the relative abundance of vectors as a function of habitat change is limited. We characterize mosquito communities across habitats with differing levels of anthropogenic ecological disturbance in central Thailand. During the 2008 rainy season, adult mosquito collections from 24 sites, representing 6 habitat types ranging from forest to urban, yielded 62,126 intact female mosquitoes (83,325 total mosquitoes) that were assigned to 109 taxa. Female mosquito abundance was highest in rice fields and lowest in forests. Diversity indices and rarefied species richness estimates indicate the mosquito fauna was more diverse in rural and less diverse in rice field habitats, while extrapolated estimates of true richness (Chao1 and ACE) indicated higher diversity in the forest and fragmented forest habitats and lower diversity in the urban. Culex sp. (Vishnui subgroup) was the most common taxon found overall and the most frequent in fragmented forest, rice field, rural, and suburban habitats. The distributions of species of medical importance differed significantly across habitat types and were always lowest in the intact, forest habitat. The relative abundance of key vector species, Aedes aegypti and Culex quinquefasciatus, was negatively correlated with diversity, suggesting that direct species interactions and/or habitat-mediated factors differentially affecting invasive disease vectors may be important mechanisms linking biodiversity loss to human health. Our results are an important first step for understanding the dynamics of mosquito vector distributions under changing environmental features across landscapes of Thailand.

  19. Mosquito Vector Diversity across Habitats in Central Thailand Endemic for Dengue and Other Arthropod-Borne Diseases

    PubMed Central

    Thongsripong, Panpim; Green, Amy; Kittayapong, Pattamaporn; Kapan, Durrell; Wilcox, Bruce; Bennett, Shannon

    2013-01-01

    Recent years have seen the greatest ecological disturbances of our times, with global human expansion, species and habitat loss, climate change, and the emergence of new and previously-known infectious diseases. Biodiversity loss affects infectious disease risk by disrupting normal relationships between hosts and pathogens. Mosquito-borne pathogens respond to changing dynamics on multiple transmission levels and appear to increase in disturbed systems, yet current knowledge of mosquito diversity and the relative abundance of vectors as a function of habitat change is limited. We characterize mosquito communities across habitats with differing levels of anthropogenic ecological disturbance in central Thailand. During the 2008 rainy season, adult mosquito collections from 24 sites, representing 6 habitat types ranging from forest to urban, yielded 62,126 intact female mosquitoes (83,325 total mosquitoes) that were assigned to 109 taxa. Female mosquito abundance was highest in rice fields and lowest in forests. Diversity indices and rarefied species richness estimates indicate the mosquito fauna was more diverse in rural and less diverse in rice field habitats, while extrapolated estimates of true richness (Chao1 and ACE) indicated higher diversity in the forest and fragmented forest habitats and lower diversity in the urban. Culex sp. (Vishnui subgroup) was the most common taxon found overall and the most frequent in fragmented forest, rice field, rural, and suburban habitats. The distributions of species of medical importance differed significantly across habitat types and were always lowest in the intact, forest habitat. The relative abundance of key vector species, Aedes aegypti and Culex quinquefasciatus, was negatively correlated with diversity, suggesting that direct species interactions and/or habitat-mediated factors differentially affecting invasive disease vectors may be important mechanisms linking biodiversity loss to human health. Our results are an important first step for understanding the dynamics of mosquito vector distributions under changing environmental features across landscapes of Thailand. PMID:24205420

  20. Cover crops and related methods for enhancing agricultural diversity and conservation biocontrol: Successful case studies

    USDA-ARS?s Scientific Manuscript database

    The book explores ways in which biodiversity can be harnessed to achieve sustainable insect pest management. Vegetation diversification at scales ranging from the individual field to the landscape can lead to direct reductions in pest numbers. This chapter will be one of several in the penultimate s...

  1. Urban forestry: The final frontier?

    Treesearch

    E.G. McPherson

    2003-01-01

    Forestry and urban forestry have more in common than practitioners in either field may think. The two disciplines could each take better advantage of the other’s expertise, such as foresters' impressive range of scientific theory and technological sophistication, and urban foresters' experience in working with diverse stakeholders in the public arena. The...

  2. Science Communication Training: What Are We Trying to Teach?

    ERIC Educational Resources Information Center

    Baram-Tsabari, Ayelet; Lewenstein, Bruce V.

    2017-01-01

    Rapid growth in public communication of science and technology has led to many diverse training programs. We ask: What are learning goals of science communication training? A comprehensive set of learning goals for future trainings will draw fully from the range of fields that contribute to science communication. Learning goals help decide what to…

  3. Geology and geochemistry of volcanic centers within the eastern half of the Sonoma volcanic field, northern San Francisco Bay region, California

    USGS Publications Warehouse

    Sweetkind, Donald S.; Rytuba, James J.; Langenheim, V.E.; Fleck, Robert J.

    2011-01-01

    The volcanic fields in the California Coast Ranges north of San Francisco Bay are temporally and spatially associated with the northward migration of the Mendocino triple junction and the transition from subduction and associated arc volcanism to a slab window tectonic environment. Our geochemical analyses from the Sonoma volcanic field highlight the geochemical diversity of these volcanic rocks, allowing us to clearly distinguish these volcanic rocks from those of the roughly coeval ancestral Cascades magmatic arc to the west, and also to compare rocks of the Sonoma volcanic field to rocks from other slab window settings.

  4. Perspectives on the history of evo-devo and the contemporary research landscape in the genomics era.

    PubMed

    Tickle, Cheryll; Urrutia, Araxi O

    2017-02-05

    A fundamental question in biology is how the extraordinary range of living organisms arose. In this theme issue, we celebrate how evolutionary studies on the origins of morphological diversity have changed over the past 350 years since the first publication of the Philosophical Transactions of The Royal Society Current understanding of this topic is enriched by many disciplines, including anatomy, palaeontology, developmental biology, genetics and genomics. Development is central because it is the means by which genetic information of an organism is translated into morphology. The discovery of the genetic basis of development has revealed how changes in form can be inherited, leading to the emergence of the field known as evolutionary developmental biology (evo-devo). Recent approaches include imaging, quantitative morphometrics and, in particular, genomics, which brings a new dimension. Articles in this issue illustrate the contemporary evo-devo field by considering general principles emerging from genomics and how this and other approaches are applied to specific questions about the evolution of major transitions and innovations in morphology, diversification and modification of structures, intraspecific morphological variation and developmental plasticity. Current approaches enable a much broader range of organisms to be studied, thus building a better appreciation of the origins of morphological diversity.This article is part of the themed issue 'Evo-devo in the genomics era, and the origins of morphological diversity'. © 2016 The Author(s).

  5. Honey bee foraging ecology: Season but not landscape diversity shapes the amount and diversity of collected pollen

    PubMed Central

    Keller, Alexander; Härtel, Stephan; Steffan-Dewenter, Ingolf

    2017-01-01

    The availability of pollen in agricultural landscapes is essential for the successful growth and reproduction of honey bee colonies (Apis mellifera L.). The quantity and diversity of collected pollen can influence the growth and health of honey bee colonies, but little is known about the influence of landscape structure on pollen diet. In a field experiment, we rotated 16 honey bee colonies across 16 agricultural landscapes, used traps to collect samples of collected pollen and observed intra-colonial dance communication to gain information about foraging distances. DNA metabarcoding was applied to analyze mixed pollen samples. Neither the amount of collected pollen nor pollen diversity was related to landscape diversity. However, we found a strong seasonal variation in the amount and diversity of collected pollen in all sites independent of landscape diversity. The observed increase in foraging distances with decreasing landscape diversity suggests that honey bees compensated for lower landscape diversity by increasing their pollen foraging range in order to maintain pollen amount and diversity. Our results underscore the importance of a diverse pollen diet for honey bee colonies. Agri-environmental schemes aiming to support pollinators should focus on possible spatial and temporal gaps in pollen availability and diversity in agricultural landscapes. PMID:28854210

  6. Honey bee foraging ecology: Season but not landscape diversity shapes the amount and diversity of collected pollen.

    PubMed

    Danner, Nadja; Keller, Alexander; Härtel, Stephan; Steffan-Dewenter, Ingolf

    2017-01-01

    The availability of pollen in agricultural landscapes is essential for the successful growth and reproduction of honey bee colonies (Apis mellifera L.). The quantity and diversity of collected pollen can influence the growth and health of honey bee colonies, but little is known about the influence of landscape structure on pollen diet. In a field experiment, we rotated 16 honey bee colonies across 16 agricultural landscapes, used traps to collect samples of collected pollen and observed intra-colonial dance communication to gain information about foraging distances. DNA metabarcoding was applied to analyze mixed pollen samples. Neither the amount of collected pollen nor pollen diversity was related to landscape diversity. However, we found a strong seasonal variation in the amount and diversity of collected pollen in all sites independent of landscape diversity. The observed increase in foraging distances with decreasing landscape diversity suggests that honey bees compensated for lower landscape diversity by increasing their pollen foraging range in order to maintain pollen amount and diversity. Our results underscore the importance of a diverse pollen diet for honey bee colonies. Agri-environmental schemes aiming to support pollinators should focus on possible spatial and temporal gaps in pollen availability and diversity in agricultural landscapes.

  7. Engineered magnetic nanoparticles for biomedical applications.

    PubMed

    Canfarotta, Francesco; Piletsky, Sergey A

    2014-02-01

    In the past decades, magnetic nanoparticles (MNPs) have been used in wide range of diverse applications, ranging from separation to sensing. Here, synthesis and applications of functionalized MNPs in the biomedical field are discussed, in particular in drug delivery, imaging, and cancer therapy, highlighting also recent progresses in the development of multifunctional and stimuli-responsive MNPs. The role of their size, composition, and surface functionalization is analyzed, together with their biocompatibility issues. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Design for mosquito abundance, diversity, and phenology sampling within the National Ecological Observatory Network

    USGS Publications Warehouse

    Hoekman, D.; Springer, Yuri P.; Barker, C.M.; Barrera, R.; Blackmore, M.S.; Bradshaw, W.E.; Foley, D. H.; Ginsberg, Howard; Hayden, M. H.; Holzapfel, C. M.; Juliano, S. A.; Kramer, L. D.; LaDeau, S. L.; Livdahl, T. P.; Moore, C. G.; Nasci, R.S.; Reisen, W.K.; Savage, H. M.

    2016-01-01

    The National Ecological Observatory Network (NEON) intends to monitor mosquito populations across its broad geographical range of sites because of their prevalence in food webs, sensitivity to abiotic factors and relevance for human health. We describe the design of mosquito population sampling in the context of NEON’s long term continental scale monitoring program, emphasizing the sampling design schedule, priorities and collection methods. Freely available NEON data and associated field and laboratory samples, will increase our understanding of how mosquito abundance, demography, diversity and phenology are responding to land use and climate change.

  9. Anelastic spherical dynamos with radially variable electrical conductivity

    NASA Astrophysics Data System (ADS)

    Dietrich, W.; Jones, C. A.

    2018-05-01

    A series of numerical simulations of the dynamo process operating inside gas giant planets has been performed. We use an anelastic, fully nonlinear, three-dimensional, benchmarked MHD code to evolve the flow, entropy and magnetic field. Our models take into account the varying electrical conductivity, high in the ionised metallic hydrogen region, low in the molecular outer region. Our suite of electrical conductivity profiles ranges from Jupiter-like, where the outer hydrodynamic region is quite thin, to Saturn-like, where there is a thick non-conducting shell. The rapid rotation leads to the formation of two distinct dynamical regimes which are separated by a magnetic tangent cylinder - mTC. Outside the mTC there are strong zonal flows, where Reynolds stress balances turbulent viscosity, but inside the mTC Lorentz force reduces the zonal flow. The dynamic interaction between both regions induces meridional circulation. We find a rich diversity of magnetic field morphologies. There are Jupiter-like steady dipolar fields, and a belt of quadrupolar dominated dynamos spanning the range of models between Jupiter-like and Saturn-like conductivity profiles. This diversity may be linked to the appearance of reversed sign helicity in the metallic regions of our dynamos. With Saturn-like conductivity profiles we find models with dipolar magnetic fields, whose axisymmetric components resemble those of Saturn, and which oscillate on a very long time-scale. However, the non-axisymmetric field components of our models are at least ten times larger than those of Saturn, possibly due to the absence of any stably stratified layer.

  10. "Savoir Fare": Are Cooking Skills a New Morality?

    ERIC Educational Resources Information Center

    Coveney, John; Begley, Andrea; Gallegos, Danielle

    2012-01-01

    There has been a recent surge of interest in cooking skills in a diverse range of fields, such as health, education and public policy. There appears to be an assumption that cooking skills are in decline and that this is having an adverse impact on individual health and well-being, and family wholesomeness. The problematisation of cooking skills…

  11. Time Resolved Microfluorescence In Biomedical Diagnosis

    NASA Astrophysics Data System (ADS)

    Schneckenburger, Herbert

    1985-12-01

    A measuring system combining subnanosecond laser-induced fluorescence with microscopic signal detection was installed and used for diverse projects in the biomedical and environmental fields. These projects range from tumor diagnosis and enzymatic analysis to measurements of the activity of methanogenic bacteria, which affect biogas production and waste water cleaning. The advantages of this method and its practical applicability are discussed.

  12. Educational Challenges of Molecular Life Science: Characteristics and Implications for Education and Research

    ERIC Educational Resources Information Center

    Tibell, Lena A. E.; Rundgren, Carl-Johan

    2010-01-01

    Molecular life science is one of the fastest-growing fields of scientific and technical innovation, and biotechnology has profound effects on many aspects of daily life--often with deep, ethical dimensions. At the same time, the content is inherently complex, highly abstract, and deeply rooted in diverse disciplines ranging from "pure…

  13. The Unit of Analysis in Mathematics Education: Bridging the Political-Technical Divide?

    ERIC Educational Resources Information Center

    Ernest, Paul

    2016-01-01

    Mathematics education is a complex, multi-disciplinary field of study which treats a wide range of diverse but interrelated areas. These include the nature of mathematics, the learning of mathematics, its teaching, and the social context surrounding both the discipline and applications of mathematics itself, as well as its teaching and learning.…

  14. Academic Boredom among Students in Higher Education: A Mixed-Methods Exploration of Characteristics, Contributors and Consequences

    ERIC Educational Resources Information Center

    Sharp, John G.; Hemmings, Brian; Kay, Russell; Murphy, Barbara; Elliott, Sam

    2017-01-01

    Academic boredom usually contributes adversely towards student engagement and performance across a diverse range of settings including universities. The formal study of academic boredom in higher education remains, however, a relatively underdeveloped field and one surprisingly neglected in the UK. Rooted in Control-Value Theory, details of a…

  15. Future applications of electronic-nose technologies in healthcare and biomedicine

    Treesearch

    Alphus D. Wilson

    2011-01-01

    The development and utilization of many new electronic-nose (e-nose) applications in the healthcare and biomedical fields have continued to rapidly accelerate over the past 20 years. Innovative e-nose technologies are providing unique solutions to a diversity of complex problems in biomedicine that are now coming to fruition. A wide range of electronic-nose instrument...

  16. Highlights from the Faraday Discussion on Ionic Liquids: From Fundamental Properties to Practical Applications, Cambridge, UK, September 2017.

    PubMed

    Aldous, Leigh; Bendova, Magdalena; Gonzalez-Miquel, Maria; Swadźba-Kwaśny, Małgorzata

    2018-05-22

    For the third time, a Faraday Discussion addressed ionic liquids. Encompassing the wealth of research in this field, the contributions ranged from fundamental insights to the diverse applications of ionic liquids. Lively discussions initiated in the lecture hall and during poster sessions then seamlessly continued during the social program.

  17. Species diversity of ostracods (Crustacea: Ostracoda) from rice fields in Northeast Thailand, with the description of a new Tanycypris species.

    PubMed

    Savatenalinton, Sukonthip

    2017-12-07

    The species diversity of ostracods in rice fields from Northeast Thailand was studied. Fifty-two samples were collected from 43 rice fields during 2010-2016. This investigation revealed 23 genera and 52 species, including one new to science (Tanycypris eugenkempfi n. sp.) and 21 endemic species: endemic to the Oriental region (14 species), Southeast Asia (two species) and Thailand (five species). In addition, two species that were restricted to rice fields in this study were recognized: Bradleytriebella tuberculata (Hartmann, 1964) and Notodromas sinensis Neale & Zhao, 1991. The most diverse genus was Pseudostrandesia, followed by Strandesia with eight and five species, respectively. The most widely distributed species were Pseudocypretta maculata Klie, 1932 and Strandesia kraepelini (G.W. Müller, 1906) occurring in 48.8 % of the total of surveyed rice fields. The number of species in individual rice fields ranged from none to 18. Most of the samples contained three species, but one rice field showed very high species richness (18 species). Most of the species recorded in this study were also found in several types of water bodies and reported from several zoogeographical regions. The main distinguishing characters between Tanycypris eugenkempfi n. sp. and other Tanycypris species are the more tumid carapace in dorsal view, the distinctly arched dorsal margin of the carapace in lateral view, the presence of a subapical dorsal seta on the first segment of the first antenna, the smooth large bristles on the third endite of the maxillula, the absence of c-seta on the first thoracopod, and the long proximal claw (Gp) of the caudal ramus.

  18. Preservation of the genetic diversity of a local common carp in the agricultural heritage rice–fish system

    PubMed Central

    Ren, Weizheng; Hu, Liangliang; Guo, Liang; Zhang, Jian; Tang, Lu; Zhang, Entao; Zhang, Jiaen; Luo, Shiming; Tang, Jianjun; Chen, Xin

    2018-01-01

    We examined how traditional farmers preserve the genetic diversity of a local common carp (Cyprinus carpio), which is locally referred to as “paddy field carp” (PF-carp), in a “globally important agricultural heritage system” (GIAHS), i.e., the 1,200-y-old rice–fish coculture system in Zhejiang Province, China. Our molecular and morphological analysis showed that the PF-carp has changed into a distinct local population with higher genetic diversity and diverse color types. Within this GIAHS region, PF-carps exist as a continuous metapopulation, although three genetic groups could be identified by microsatellite markers. Thousands of small farmer households interdependently obtained fry and parental carps for their own rice–fish production, resulting in a high gene flow and large numbers of parent carps distributing in a mosaic pattern in the region. Landscape genetic analysis indicated that farmers’ connectivity was one of the major factors that shaped this genetic pattern. Population viability analysis further revealed that the numbers of these interconnected small farmer households and their connection intensity affect the carps’ inherent genetic diversity. The practice of mixed culturing of carps with diverse color types helped to preserve a wide range of genetic resources in the paddy field. This widespread traditional practice increases fish yield and resource use, which, in return, encourages famers to continue their practice of selecting and conserving diverse color types of PF-carp. Our results suggested that traditional farmers secure the genetic diversity of PF-carp and its viability over generations in this region through interdependently incubating and mixed-culturing practices within the rice−fish system. PMID:29295926

  19. The 2017 Plasma Roadmap: Low temperature plasma science and technology

    NASA Astrophysics Data System (ADS)

    Adamovich, I.; Baalrud, S. D.; Bogaerts, A.; Bruggeman, P. J.; Cappelli, M.; Colombo, V.; Czarnetzki, U.; Ebert, U.; Eden, J. G.; Favia, P.; Graves, D. B.; Hamaguchi, S.; Hieftje, G.; Hori, M.; Kaganovich, I. D.; Kortshagen, U.; Kushner, M. J.; Mason, N. J.; Mazouffre, S.; Mededovic Thagard, S.; Metelmann, H.-R.; Mizuno, A.; Moreau, E.; Murphy, A. B.; Niemira, B. A.; Oehrlein, G. S.; Petrovic, Z. Lj; Pitchford, L. C.; Pu, Y.-K.; Rauf, S.; Sakai, O.; Samukawa, S.; Starikovskaia, S.; Tennyson, J.; Terashima, K.; Turner, M. M.; van de Sanden, M. C. M.; Vardelle, A.

    2017-08-01

    Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012 consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic updates of the Plasma Roadmap. The continuously growing interdisciplinary nature of the low temperature plasma field and its equally broad range of applications are making it increasingly difficult to identify major challenges that encompass all of the many sub-fields and applications. This intellectual diversity is ultimately a strength of the field. The current state of the art for the 19 sub-fields addressed in this roadmap demonstrates the enviable track record of the low temperature plasma field in the development of plasmas as an enabling technology for a vast range of technologies that underpin our modern society. At the same time, the many important scientific and technological challenges shared in this roadmap show that the path forward is not only scientifically rich but has the potential to make wide and far reaching contributions to many societal challenges.

  20. Genetic diversity of Babesia bovis in virulent and attenuated strains.

    PubMed

    Mazuz, M L; Molad, T; Fish, L; Leibovitz, B; Wolkomirsky, R; Fleiderovitz, L; Shkap, V

    2012-03-01

    The aim of this study was to compare the genetic diversity of the single copy Bv80 gene sequences of Babesia bovis in populations of attenuated and virulent parasites. PCR/ RT-PCR followed by cloning and sequence analyses of 4 attenuated and 4 virulent strains were performed. Multiple fragments in the range of 420 to 744 bp were amplified by PCR or RT-PCR. Cloning of the PCR fragments and sequence analyses revealed the presence of mixed subpopulations in either virulent or attenuated parasites with a total of 19 variants with 12 different sequences that differed in number and type of tandem repeats. High levels of intra- and inter-strain diversity of the Bv80 gene, with the presence of mixed populations of parasites were found in both the virulent field isolates and the attenuated vaccine strains. In addition, during the attenuation process, sequence analyses showed changes in the pattern of the parasite subpopulations. Despite high polymorphism found by sequence analyses, the patterns observed and the number of repeats, order, or motifs found could not discriminate between virulent field isolates and attenuated vaccine strains of the parasite.

  1. Unusual polarity-dependent patterns in a bent-core nematic liquid crystal under low-frequency ac field.

    PubMed

    Xiang, Ying; Zhou, Meng-jie; Xu, Ming-Ya; Salamon, Péter; Éber, Nándor; Buka, Ágnes

    2015-04-01

    Electric-field-induced patterns of diverse morphology have been observed over a wide frequency range in a recently synthesized bent-core nematic (BCN) liquid crystal. At low frequencies (up to ∼25 Hz), the BCN exhibited unusual polarity-dependent patterns. When the amplitude of the ac field was enhanced, these two time-asymmetrical patterns turned into time-symmetrical prewavylike stripes. At ac frequencies in the middle-frequency range (∼50-3000 Hz), zigzag patterns were detected whose obliqueness varied with the frequency. Finally, if the frequency was increased above 3 kHz, the zigzag pattern was replaced by another, prewavylike pattern, whose threshold voltage depended on the frequency; however, the wave vector did not. For a more complete characterization, material parameters such as elastic constants, dielectric permittivities, and the anisotropy of the diamagnetic susceptibility were also determined.

  2. Estimates of effective population size and inbreeding in South African indigenous chicken populations: implications for the conservation of unique genetic resources.

    PubMed

    Mtileni, Bohani; Dzama, Kennedy; Nephawe, Khathutshelo; Rhode, Clint

    2016-06-01

    Conservation of locally adapted indigenous livestock breeds has become an important objective in sustainable animal breeding, as these breeds represent a unique genetic resource. Therefore, the Agricultural Research Council of South Africa initiated a conservation programme for four South African indigenous chicken breeds. The evaluation and monitoring of the genetic constitution of these conservation flocks is important for proper management of the conservation programme. Using molecular genetic analyses, the effective population sizes and relatedness of these conservation flocks were compared to village (field) chicken populations from which they were derived. Genetic diversity within and between these populations are further discussed within the context of population size. The conservation flocks for the respective breeds had relatively small effective population sizes (point estimate range 38.6-78.6) in comparison to the field populations (point estimate range 118.9-580.0). Furthermore, evidence supports a transient heterozygous excess, generally associated with the occurrence of a recent population bottleneck. Genetic diversity, as measured by the number of alleles, heterozygosity and information index, was also significantly reduced in the conservation flocks. The average relatedness amongst the conservation flocks was high, whilst it remained low for the field populations. There was also significant evidence for population differentiation between field and conservation populations. F st estimates for conservation flocks were moderate to high with a maximum reached between VD_C and VD_F (0.285). However, F st estimates for field population were excessively low between the NN_C and EC_F (0.007) and between EC_F and OV_F (0.009). The significant population differentiation of the conservation flocks from their geographically correlated field populations of origin is further supported by the analysis of molecular variance (AMOVA), with 10.51 % of genetic diversity ascribed to population differences within groups (F SC = 0.106). The results suggest that significant genetic erosion has occurred within the conservation flocks due to inbreeding, pronounced effects of random drift and selection. It might be necessary to introduce new breeding individuals from the respective field populations in order to increase the effective population sizes of the conservation flocks and counter the effects of genetic erosion.

  3. Preparing the NDE engineers of the future: Education, training, and diversity

    NASA Astrophysics Data System (ADS)

    Holland, Stephen D.

    2017-02-01

    As quantitative NDE has matured and entered the mainstream, it has created an industry need for engineers who can select, evaluate, and qualify NDE techniques to satisfy quantitative engineering requirements. NDE as a field is cross-disciplinary with major NDE techniques relying on a broad spectrum of physics disciplines including fluid mechanics, electromagnetics, mechanical waves, and high energy physics. An NDE engineer needs broad and deep understanding of the measurement physics across modalities, a general engineering background, and familiarity with shop-floor practices and tools. While there are a wide range of certification and training programs worldwide for NDE technicians, there are few programs aimed at engineers. At the same time, substantial demographic shifts are underway with many experienced NDE engineers and technicians nearing retirement, and with new generations coming from much more diverse backgrounds. There is a need for more and better education opportunities for NDE engineers. Both teaching and learning NDE engineering are inherently challenging because of the breadth and depth of knowledge required. At the same time, sustaining the field in a more diverse era will require broadening participation of previously underrepresented groups. The QNDE 2016 conference in Atlanta, GA included a session on NDE education, training, and diversity. This paper summarizes the outcomes and discussion from this session.

  4. Policy Implications at the State and District Level with RtI for Gifted students

    ERIC Educational Resources Information Center

    Brown, Elissa F.; Abernethy, Sherry H.

    2009-01-01

    As a field, gifted education does not endorse any one approach to serving students because of the range of student abilities and resulting concomitant diverse needs. Therefore, service delivery in gifted education is still heavily teacher dependent. Yet, many of the components of Response to Intervention (RtI) are employed in gifted education,…

  5. Hamiltonian methods: BRST, BFV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Garcia, J. Antonio

    2006-09-25

    The range of applicability of Hamiltonian methods to gauge theories is very diverse and cover areas of research from phenomenology to mathematical physics. We review some of the areas developed in Mexico in the last decades. They cover the study of symplectic methods, BRST-BFV and BV approaches, Klauder projector program, and non perturbative technics used in the study of bound states in relativistic field theories.

  6. Hamiltonian methods: BRST, BFV

    NASA Astrophysics Data System (ADS)

    García, J. Antonio

    2006-09-01

    The range of applicability of Hamiltonian methods to gauge theories is very diverse and cover areas of research from phenomenology to mathematical physics. We review some of the areas developed in México in the last decades. They cover the study of symplectic methods, BRST-BFV and BV approaches, Klauder projector program, and non perturbative technics used in the study of bound states in relativistic field theories.

  7. Time-Resolved Microfluorescence In Biomedical Diagnosis

    NASA Astrophysics Data System (ADS)

    Schneckenburger, Herbert

    1985-02-01

    A measuring system combining subnanosecond laser-induced fluorescence with microscopic signal detection was installed and used for diverse projects in the biomedical and environmental field. These projects are ranging from tumor diagnosis and enzymatic analysis to measurements of the activity of methanogenic bacteria which effect biogas production and waste water cleaning. The advantages of this method and its practical applicability are discussed.

  8. The Teacher Educator's Handbook: Building a Knowledge Base for the Preparation of Teachers. The Jossey-Bass Education Series.

    ERIC Educational Resources Information Center

    Murray, Frank B., Ed.

    In this book, leading scholars address a range of issues, ideas, and research findings in the field of teacher education, examining specific disciplines, social foundations, and program structures, as well as school reform and diversity. Part One: The Need for a Knowledge Base contains five chapters: "Beyond Natural Teaching: The Case for…

  9. Adaptive management of natural resources: theory, concepts, and management institutions.

    Treesearch

    George H. Stankey; Roger N. Clark; Bernard T. Bormann

    2005-01-01

    This report reviews the extensive and growing literature on the concept and application of adaptive management. Adaptive management is a central element of the Northwest Forest Plan and there is a need for an informed understanding of the key theories, concepts, and frameworks upon which it is founded. Literature from a diverse range of fields including social learning...

  10. Gate-tunable carbon nanotube-MoS2 heterojunction p-n diode.

    PubMed

    Jariwala, Deep; Sangwan, Vinod K; Wu, Chung-Chiang; Prabhumirashi, Pradyumna L; Geier, Michael L; Marks, Tobin J; Lauhon, Lincoln J; Hersam, Mark C

    2013-11-05

    The p-n junction diode and field-effect transistor are the two most ubiquitous building blocks of modern electronics and optoelectronics. In recent years, the emergence of reduced dimensionality materials has suggested that these components can be scaled down to atomic thicknesses. Although high-performance field-effect devices have been achieved from monolayered materials and their heterostructures, a p-n heterojunction diode derived from ultrathin materials is notably absent and constrains the fabrication of complex electronic and optoelectronic circuits. Here we demonstrate a gate-tunable p-n heterojunction diode using semiconducting single-walled carbon nanotubes (SWCNTs) and single-layer molybdenum disulfide as p-type and n-type semiconductors, respectively. The vertical stacking of these two direct band gap semiconductors forms a heterojunction with electrical characteristics that can be tuned with an applied gate bias to achieve a wide range of charge transport behavior ranging from insulating to rectifying with forward-to-reverse bias current ratios exceeding 10(4). This heterojunction diode also responds strongly to optical irradiation with an external quantum efficiency of 25% and fast photoresponse <15 μs. Because SWCNTs have a diverse range of electrical properties as a function of chirality and an increasing number of atomically thin 2D nanomaterials are being isolated, the gate-tunable p-n heterojunction concept presented here should be widely generalizable to realize diverse ultrathin, high-performance electronics and optoelectronics.

  11. Gate-tunable carbon nanotube–MoS2 heterojunction p-n diode

    PubMed Central

    Jariwala, Deep; Sangwan, Vinod K.; Wu, Chung-Chiang; Prabhumirashi, Pradyumna L.; Geier, Michael L.; Marks, Tobin J.; Lauhon, Lincoln J.; Hersam, Mark C.

    2013-01-01

    The p-n junction diode and field-effect transistor are the two most ubiquitous building blocks of modern electronics and optoelectronics. In recent years, the emergence of reduced dimensionality materials has suggested that these components can be scaled down to atomic thicknesses. Although high-performance field-effect devices have been achieved from monolayered materials and their heterostructures, a p-n heterojunction diode derived from ultrathin materials is notably absent and constrains the fabrication of complex electronic and optoelectronic circuits. Here we demonstrate a gate-tunable p-n heterojunction diode using semiconducting single-walled carbon nanotubes (SWCNTs) and single-layer molybdenum disulfide as p-type and n-type semiconductors, respectively. The vertical stacking of these two direct band gap semiconductors forms a heterojunction with electrical characteristics that can be tuned with an applied gate bias to achieve a wide range of charge transport behavior ranging from insulating to rectifying with forward-to-reverse bias current ratios exceeding 104. This heterojunction diode also responds strongly to optical irradiation with an external quantum efficiency of 25% and fast photoresponse <15 μs. Because SWCNTs have a diverse range of electrical properties as a function of chirality and an increasing number of atomically thin 2D nanomaterials are being isolated, the gate-tunable p-n heterojunction concept presented here should be widely generalizable to realize diverse ultrathin, high-performance electronics and optoelectronics. PMID:24145425

  12. Diversity of bees and their floral resources at altitudinal areas in the Southern Espinhaço Range, Minas Gerais, Brazil.

    PubMed

    Araújo, Vinícius A; Antonini, Yasmine; Araújo, Ana P A

    2006-01-01

    The Southern Espinhaço Range consists of large areas covered by quartzitic or metaliferous tropical altitudinal fields. The Espinhaço Range ecosystems are endangered by anthropic high impacts, particularly due to mining and urbanization. We conducted a one-year inventory of the bee flora and fauna at the quartzitic Ouro Branco Mountains and a two-year survey of the metaliferous Ouro Preto fields. The samples were collected twice a month, from 8:00 am to 5:00 pm. The bees (677) belonged to 91 species, five families. The family Apidae was the richest and most abundant, followed by the Halictidae and Megachilidae. The bees visited 46 flowering plant species; the most visited plants were the Asteraceae (n = 220), the Malpighiaceae (n = 95), the Melastomataceae (n = 94), the Fabaceae (n = 78), and the Solanaceae (n = 63). Diversity was higher in Ouro Branco (H = 1.47) than in Ouro Preto (H = 1.17). The low richness and abundance of bees in our research site when compared to other Brazilian "Cerrado" areas can be due to the high altitude, low temperature, and low availability of flowers we found. "Canga" and rupestrian areas house fauna and flora species that are rare and threatened by extinction. The southern Espinhaço areas can, therefore, be given the status of permanent biodiversity preservation area.

  13. Multicontext Diversity: The critical dimension of diversity that can attract students and help them thrive

    NASA Astrophysics Data System (ADS)

    Weissmann, G. S.; Ibarra, R.; Howland-Davis, M.

    2017-12-01

    Diversity programs on college campuses have expanded over the past several decades, bringing a broad range of students to academia; however, these programs have not resulted in diversification of faculty or PhD students. Current diversity programs generally focus on two dimensions of diversity: (1) structural diversity, which aims to bring in students from underrepresented groups to college campuses through scholarships, admissions policies, and targeted marketing; and (2) multicultural diversity, which uses programs designed to give students from underrepresented groups homes on campus and programs designed to study cultural aspects of different groups. Though these programs are important, something else must be controlling the lack of minority participation in STEM at advanced levels. We posit that a third dimension of diversity, context diversity, is lacking in university education, especially in STEM fields, and without accessing this form of diversity, programs will never benefit from the broader diversity of society. Context diversity results through application of Multicontext theory, which both explains and predicts the inclusion of exclusion of people within an institutional culture. It describes how different cultures approach understanding the world around them. This "cultural ways of knowing and doing" has been described using a binary system, consisting of "Low Context" and "High Context" cultures. Ibarra (2001) described how a spectrum exists between these end members, and thus individuals brought up in different cultures will understand the world from somewhere along this context diversity spectrum. Academic culture tends to fall on the low context side of the spectrum. Thus, students (and faculty) who come from cultures that tend toward the high context side of the spectrum often feel excluded from the academic setting, especially in STEM fields which tend to be strongly low context in nature. A high percentage of students from underrepresented groups and women tend to fall on toward the high context side of the spectrum, thus this disproportionately affects women and minorities. Multicontextuality can be readily applied in classroom and research settings, thus leading to helping all students thrive in the academic setting.

  14. Plasmonic Fiber Optic Refractometric Sensors: From Conventional Architectures to Recent Design Trends

    PubMed Central

    Klantsataya, Elizaveta; Jia, Peipei; Ebendorff-Heidepriem, Heike; Monro, Tanya M.; François, Alexandre

    2016-01-01

    Surface Plasmon Resonance (SPR) fiber sensor research has grown since the first demonstration over 20 year ago into a rich and diverse field with a wide range of optical fiber architectures, plasmonic coatings, and excitation and interrogation methods. Yet, the large diversity of SPR fiber sensor designs has made it difficult to understand the advantages of each approach. Here, we review SPR fiber sensor architectures, covering the latest developments from optical fiber geometries to plasmonic coatings. By developing a systematic approach to fiber-based SPR designs, we identify and discuss future research opportunities based on a performance comparison of the different approaches for sensing applications. PMID:28025532

  15. The Grism Lens-Amplified Survey from Space (GLASS). VII. The Diversity of the Distribution of Star Formation in Cluster and Field Galaxies at 0.3 less than or equal to z less than or equal to 0.7

    NASA Astrophysics Data System (ADS)

    Vulcani, Benedetta; Treu, Tommaso; Schmidt, Kasper B.; Morishita, Takahiro; Dressler, Alan; Poggianti, Bianca M.; Abramson, Louis; Bradač, Marusa; Brammer, Gabriel B.; Hoag, Austin; Malkan, Matthew; Pentericci, Laura; Trenti, Michele

    2016-12-01

    Exploiting the slitless spectroscopy taken as part of the Grism Lens-Amplified Survey from Space (GLASS), we present an extended analysis of the spatial distribution of star formation in 76 galaxies in 10 clusters at 0.3\\lt z\\lt 0.7. We use 85 foreground and background galaxies in the same redshift range as a field sample. The samples are well matched in stellar mass (108-1011 {M}⊙ ) and star formation rate (0.5-50 {M}⊙ {{yr}}-1). We visually classify galaxies in terms of broad band morphology, Hα morphology, and likely physical process acting on the galaxy. Most Hα emitters have a spiral morphology (41% ± 8% in clusters, 51% ± 8% in the field), followed by mergers/interactions (28% ± 8%, 31% ± 7%, respectively) and early-type galaxies (remarkably as high as 29% ± 8% in clusters and 15% ± 6% in the field). A diversity of Hα morphologies is detected, suggesting a diversity of physical processes. In clusters, 30% ± 8% of the galaxies present a regular morphology, mostly consistent with star formation diffused uniformly across the stellar population (mostly in the disk component, when present). The second most common morphology (28% ± 8%) is asymmetric/jellyfish, consistent with ram-pressure stripping or other non-gravitational processes in 18% ± 8% of the cases. Ram-pressure stripping appears significantly less prominent in the field (2% ± 2%), where the most common morphology/mechanism appears to be consistent with minor gas-rich mergers or clump accretion. This work demonstrates that while environment-specific mechanisms affect galaxy evolution at this redshift, they are diverse and their effects are subtle. A full understanding of this complexity requires larger samples and detailed and spatially resolved physical models.

  16. Elevational Patterns in Archaeal Diversity on Mt. Fuji

    PubMed Central

    Singh, Dharmesh; Takahashi, Koichi; Adams, Jonathan M.

    2012-01-01

    Little is known of how archaeal diversity and community ecology behaves along elevational gradients. We chose to study Mount Fuji of Japan as a geologically and topographically uniform mountain system, with a wide range of elevational zones. PCR-amplified soil DNA for the archaeal 16 S rRNA gene was pyrosequenced and taxonomically classified against EzTaxon-e archaeal database. At a bootstrap cut-off of 80%, most of the archaeal sequences were classified into phylum Thaumarchaeota (96%) and Euryarchaeota (3.9%), with no sequences classified into other phyla. Archaeal OTU richness and diversity on Fuji showed a pronounced ‘peak’ in the mid-elevations, around 1500 masl, within the boreal forest zone, compared to the temperate forest zone below and the alpine fell-field and desert zones above. Diversity decreased towards higher elevations followed by a subtle increase at the summit, mainly due to an increase in the relative abundance of the group I.1b of Thaumarchaeota. Archaeal diversity showed a strong positive correlation with soil NH4 +, K and NO3 − . Archaeal diversity does not parallel plant diversity, although it does roughly parallel bacterial diversity. Ecological hypotheses to explain the mid diversity bulge on Fuji include intermediate disturbance effects, and the result of mid elevations combining a mosaic of upper and lower slope environments. Our findings show clearly that archaeal soil communities are highly responsive to soil environmental gradients, in terms of both their diversity and community composition. Distinct communities of archaea specific to each elevational zone suggest that many archaea may be quite finely niche-adapted within the range of soil environments. A further interesting finding is the presence of a mesophilic component of archaea at high altitudes on a mountain that is not volcanically active. This emphasizes the importance of microclimate – in this case solar heating of the black volcanic ash surface – for the ecology of soil archaea. PMID:22970233

  17. Automatic process control in anaerobic digestion technology: A critical review.

    PubMed

    Nguyen, Duc; Gadhamshetty, Venkataramana; Nitayavardhana, Saoharit; Khanal, Samir Kumar

    2015-10-01

    Anaerobic digestion (AD) is a mature technology that relies upon a synergistic effort of a diverse group of microbial communities for metabolizing diverse organic substrates. However, AD is highly sensitive to process disturbances, and thus it is advantageous to use online monitoring and process control techniques to efficiently operate AD process. A range of electrochemical, chromatographic and spectroscopic devices can be deployed for on-line monitoring and control of the AD process. While complexity of the control strategy ranges from a feedback control to advanced control systems, there are some debates on implementation of advanced instrumentations or advanced control strategies. Centralized AD plants could be the answer for the applications of progressive automatic control field. This article provides a critical overview of the available automatic control technologies that can be implemented in AD processes at different scales. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. The Divide between Diversity Training and Diversity Education: Integrating Best Practices

    ERIC Educational Resources Information Center

    King, Eden B.; Gulick, Lisa M. V.; Avery, Derek R.

    2010-01-01

    The fields of diversity training and diversity education have developed in a disconnected manner. This divide ensures that each field advances slowly and with narrow focus. The authors argue here that the divide should be bridged with attention to the best practices that diversity training and diversity education offer. By integrating the best…

  19. Wide dynamic range enrichment method of semiconducting single-walled carbon nanotubes with weak field centrifugation

    NASA Astrophysics Data System (ADS)

    Reis, Wieland G.; Tomović, Željko; Weitz, R. Thomas; Krupke, Ralph; Mikhael, Jules

    2017-03-01

    The potential of single-walled carbon nanotubes (SWCNTs) to outperform silicon in electronic application was finally enabled through selective separation of semiconducting nanotubes from the as-synthesized statistical mix with polymeric dispersants. Such separation methods provide typically high semiconducting purity samples with narrow diameter distribution, i.e. almost single chiralities. But for a wide range of applications high purity mixtures of small and large diameters are sufficient or even required. Here we proof that weak field centrifugation is a diameter independent method for enrichment of semiconducting nanotubes. We show that the non-selective and strong adsorption of polyarylether dispersants on nanostructured carbon surfaces enables simple separation of diverse raw materials with different SWCNT diameter. In addition and for the first time, we demonstrate that increased temperature enables higher purity separation. Furthermore we show that the mode of action behind this electronic enrichment is strongly connected to both colloidal stability and protonation. By giving simple access to electronically sorted SWCNTs of any diameter, the wide dynamic range of weak field centrifugation can provide economical relevance to SWCNTs.

  20. Diversity in Laboratory Animal Science: Issues and Initiatives

    PubMed Central

    Alworth, Leanne; Ardayfio, Krystal L; Blickman, Andrew; Greenhill, Lisa; Hill, William; Sharp, Patrick; Talmage, Roberta; Plaut, Victoria C; Goren, Matt J

    2010-01-01

    Since diversity in the workplace began receiving scholarly attention in the late 1980s, many corporations and institutions have invested in programs to address and manage diversity. We encourage laboratory animal science to address the challenges and to build on the strengths that personal diversity brings to our field and workplaces. Diversity is already becoming increasingly relevant in the workplace and the laboratory animal science field. By addressing issues related to diversity, laboratory animal science could benefit and potentially fulfill its goals more successfully. To date, diversity has received minimal attention from the field as a whole. However, many individuals, workplaces, and institutions in industry, academia, and the uniformed services that are intimately involved with the field of laboratory animal science are actively addressing issues concerning diversity. This article describes some of these programs and activities in industry and academia. Our intention is that this article will provide useful examples of inclusion-promoting activities and prompt further initiatives to address diversity awareness and inclusion in laboratory animal science. PMID:20353686

  1. Diversity in laboratory animal science: issues and initiatives.

    PubMed

    Alworth, Leanne; Ardayfio, Krystal L; Blickman, Andrew; Greenhill, Lisa; Hill, William; Sharp, Patrick; Talmage, Roberta; Plaut, Victoria C; Goren, Matt

    2010-03-01

    Since diversity in the workplace began receiving scholarly attention in the late 1980s, many corporations and institutions have invested in programs to address and manage diversity. We encourage laboratory animal science to address the challenges and to build on the strengths that personal diversity brings to our field and workplaces. Diversity is already becoming increasingly relevant in the workplace and the laboratory animal science field. By addressing issues related to diversity, laboratory animal science could benefit and potentially fulfill its goals more successfully. To date, diversity has received minimal attention from the field as a whole. However, many individuals, workplaces, and institutions in industry, academia, and the uniformed services that are intimately involved with the field of laboratory animal science are actively addressing issues concerning diversity. This article describes some of these programs and activities in industry and academia. Our intention is that this article will provide useful examples of inclusion-promoting activities and prompt further initiatives to address diversity awareness and inclusion in laboratory animal science.

  2. Age Factor in Business Education Students' Use of Social Networking Sites in Tertiary Institutions in Anambra State, Nigeria

    ERIC Educational Resources Information Center

    Ementa, Christiana Ngozi; Ile, Chika Madu

    2015-01-01

    There are diverse social networking sites which range from those that provide social sharing and interaction to those that provide networks for professionals within same and other fields. Social networking sites require a user to sign up, create a profile and begin sending short messages about what the user is doing or thinking. The study sought…

  3. Rock glaciers and related periglacial landforms in the Sierra Nevada, CA, USA; inventory, distribution and climatic relationships

    Treesearch

    Constance I. Millar; Robert D. Westfall

    2008-01-01

    Rock glaciers and related periglacial rock-ice features (RIFs) are abundant yet overlooked landforms in the Sierra Nevada, California, where they occur in diverse forms. We mapped 421 RIFs from field surveys, and grouped these into six classes based on morphology and location. These categories comprise a greater range of frozen-ground features than are commonly...

  4. Patterns of genetic diversity reveal multiple introductions and recurrent founder effects during range expansion in invasive populations of Geranium carolinianum (Geraniaceae)

    PubMed Central

    Shirk, R Y; Hamrick, J L; Zhang, C; Qiang, S

    2014-01-01

    Genetic diversity, and thus the adaptive potential of invasive populations, is largely based on three factors: patterns of genetic diversity in the species' native range, the number and location of introductions and the number of founding individuals per introduction. Specifically, reductions in genetic diversity (‘founder effects') should be stronger for species with low within-population diversity in their native range and few introductions of few individuals to the invasive range. We test these predictions with Geranium carolinianum, a winter annual herb native to North America and invasive in China. We measure the extent of founder effects using allozymes and microsatellites, and ask whether this is consistent with its colonization history and patterns of diversity in the native range. In the native range, genetic diversity is higher and structure is lower than expected based on life history traits. In China, our results provide evidence for multiple introductions near Nanjing, Jiangsu province, with subsequent range expansion to the west and south. Patterns of genetic diversity across China reveal weak founder effects that are driven largely by low-diversity populations at the expansion front, away from the introduction location. This suggests that reduced diversity in China has resulted from successive founder events during range expansion, and that the loss of genetic diversity in the Nanjing area was mitigated by multiple introductions from diverse source populations. This has implications for the future of G. carolinianum in China, as continued gene flow among populations should eventually increase genetic diversity within the more recently founded populations. PMID:24346497

  5. Microbial Populations in Extreme Environments: Investigations and Characterizations of the Microbiology and Geochemistry of Galapagos Island Fumaroles

    NASA Astrophysics Data System (ADS)

    Mayhew, L. E.; Childers, S. E.; Geist, D.

    2005-12-01

    The extreme physiochemical conditions, insularity, and wide range in ages of fumaroles of the Galapagos Islands provide an excellent opportunity to explore for novel microorganisms and to study life in extreme environments. This is the first study that measures microbial diversity of Galapagos fumaroles. Forty-seven samples were collected from six distinct fumarole fields on Sierra Negra and Alcedo volcanoes. Vulcan Chico, on Sierra Negra, was activated during the last eruption in 1979. Two of the other fumarole fields on Sierra Negra are associated with a long-lived fault system on the caldera floor and are therefore likely to be significantly older. The fault-associated fumaroles have widespread alteration haloes (up to 100 m in diameter) and thick deposits of native sulfur. The most vigorous of the fumarole fields on Alcedo activated in late 1993 to early 1994. The second fumarole field on Alcedo is associated with a recently extinct geyser and the third is located on a rhyolite vent. A diversity of colors was observed in the substrates at all of the fumarole fields and some may be the result of microbial activity. Collection sites were chosen on the basis of temperature and the variations in the substrate in order to obtain samples from a variety of environments. Temperatures at sample sites range from 25.0 to 178.5° C, and pH from 0 to 6. The material collected varies between sites and includes crystalline sulfur deposits, clay, sandy and rocky soils, and microbial mats. Substrate material is characterized by powder x-ray diffractometry and scanning electron microscopy and gases collected from five of the fumarole fields are being analyzed to test for chemical controls on the microbial populations. Genomic DNA is being extracted from all of the samples. Primers for Bacteria and Archaea are used for PCR amplification of the 16S rRNA gene. To date, 22 of 37 processed samples have amplifiable DNA. Microbial diversity of samples possessing amplifiable DNA is being assessed by denaturing gradient gel electrophoresis (DGGE). These results may reveal the presence of novel organisms and will provide insights into how vent age, insularity, temperature, pH, and geochemistry influence the microbial populations in extreme environments in the Galapagos Islands.

  6. Diverse Geological Applications For Basil: A 2d Finite-deformation Computational Algorithm

    NASA Astrophysics Data System (ADS)

    Houseman, Gregory A.; Barr, Terence D.; Evans, Lynn

    Geological processes are often characterised by large finite-deformation continuum strains, on the order of 100% or greater. Microstructural processes cause deformation that may be represented by a viscous constitutive mechanism, with viscosity that may depend on temperature, pressure, or strain-rate. We have developed an effective com- putational algorithm for the evaluation of 2D deformation fields produced by Newto- nian or non-Newtonian viscous flow. With the implementation of this algorithm as a computer program, Basil, we have applied it to a range of diverse applications in Earth Sciences. Viscous flow fields in 2D may be defined for the thin-sheet case or, using a velocity-pressure formulation, for the plane-strain case. Flow fields are represented using 2D triangular elements with quadratic interpolation for velocity components and linear for pressure. The main matrix equation is solved by an efficient and compact conjugate gradient algorithm with iteration for non-Newtonian viscosity. Regular grids may be used, or grids based on a random distribution of points. Definition of the prob- lem requires that velocities, tractions, or some combination of the two, are specified on all external boundary nodes. Compliant boundaries may also be defined, based on the idea that traction is opposed to and proportional to boundary displacement rate. In- ternal boundary segments, allowing fault-like displacements within a viscous medium have also been developed, and we find that the computed displacement field around the fault tip is accurately represented for Newtonian and non-Newtonian viscosities, in spite of the stress singularity at the fault tip. Basil has been applied by us and colleagues to problems that include: thin sheet calculations of continental collision, Rayleigh-Taylor instability of the continental mantle lithosphere, deformation fields around fault terminations at the outcrop scale, stress and deformation fields in and around porphyroblasts, and deformation of the subducted oceanic slab. Application of Basil to a diverse range of topics is facilitated by the use of command syntax input files that allow most aspects of the calculation to be controlled easily, together with a post-processing package, Sybil, for display and interpretation of the results. Sybil uses a menu-driven graphical interface to access a powerful combination of commands, to- gether with log files that allow repetitive tasks to be more automated

  7. MARS-OZ - A Design for a Simulated Mars Base in the Australian Outback

    NASA Astrophysics Data System (ADS)

    Willson, D.; Clarke, J. D. A.; Murphy, G.

    Mars Society Australia has developed the design of a simulated Mars base, MARS-OZ, for deployment in outback Australia. MARS-OZ will provide a platform for a diverse range of Mars analogue research in Australia. The simulated base consists of two mobile modules whose dimensions and shape approximate those of horizontally landed bent biconic spacecraft described in an earlier paper. The modules are designed to support field engineering, robotics, architectural, geological, biological and human factors research at varying levels of simulation fidelity. Non-Mars related research can also be accommodated, for example general field geology and biology, and engineering research associated with sustainable, low impact architecture. Crews of up to eight can be accommodated. In addition to its research function, the base also will serve as a centre of space education and outreach activities. The prime site for the MARS-OZ simulated base is located in the northern Flinders Ranges near Arkaroola in South Australia. This region contains many features that provide useful scientific analogues to known or possible past and present conditions on Mars from both a geological and biological perspective. The features will provide a wealth of study opportunities for crews. The very diverse terrain and regolith materials will provide ideal opportunities to field trial a range of equipment, sensors and exploration strategies. If needed, the prime site can be secured from casual visitors, allowing research into human interaction in isolation. Despite its relative isolation, the site is readily accessible by road and air from major Australian centres. This paper provides description of the configuration, design and construction of the proposed facility, its interior layout, equipment and systems fitouts, a detailed cost estimate, and its deployment. We estimate that the deployment of MARS-OZ could occur within nine months of securing funding.

  8. The 2017 Plasma Roadmap: Low temperature plasma science and technology

    DOE PAGES

    Adamovich, I.; Baalrud, S. D.; Bogaerts, A.; ...

    2017-07-14

    Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012 consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic updates of the Plasma Roadmap. The continuously growing interdisciplinary nature of the low temperature plasma field and its equally broad range of applications are making it increasingly difficult to identify major challenges that encompass all of the many sub-fields and applications. This intellectual diversity is ultimately a strength of the field. The currentmore » state of the art for the 19 sub-fields addressed in this roadmap demonstrates the enviable track record of the low temperature plasma field in the development of plasmas as an enabling technology for a vast range of technologies that underpin our modern society. At the same time, the many important scientific and technological challenges shared in this roadmap show that the path forward is not only scientifically rich but has the potential to make wide and far reaching contributions to many societal challenges.« less

  9. The 2017 Plasma Roadmap: Low temperature plasma science and technology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Adamovich, I.; Baalrud, S. D.; Bogaerts, A.

    Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012 consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic updates of the Plasma Roadmap. The continuously growing interdisciplinary nature of the low temperature plasma field and its equally broad range of applications are making it increasingly difficult to identify major challenges that encompass all of the many sub-fields and applications. This intellectual diversity is ultimately a strength of the field. The currentmore » state of the art for the 19 sub-fields addressed in this roadmap demonstrates the enviable track record of the low temperature plasma field in the development of plasmas as an enabling technology for a vast range of technologies that underpin our modern society. At the same time, the many important scientific and technological challenges shared in this roadmap show that the path forward is not only scientifically rich but has the potential to make wide and far reaching contributions to many societal challenges.« less

  10. [Spatio-temporal distribution of carabids and spiders between semi-natural field margin and the adjacent crop fields in agricultural landscape].

    PubMed

    Zhang, Xu Zhu; Han, Yin; Yu, Zhen Rong; Liu, Yun Hui

    2017-06-18

    This study was conducted before and after harvesting of wheat and maize in a typical agricultural landscape of the North China Plain. We investigated the diversity of two important natural enemy groups, carabids and spiders, using pitfall traps at crop field margin with different vegetation structures and their neighboring crop field. Throughout the comparison of the spatial and temporal distribution of the diversity of carabids and spiders in field margin and neighboring field, and the investigation of the relationship between arthropod communities and vegetation structure, this study aimed to understand the role of semi-natural field margin in biodiversity conservation of different natural enemy taxa. Results showed that the abundance of spiders was significantly higher in field margin than in neighboring fields over the entire period. No significant difference of the diversity of carabids in field margin and crop field was observed, but the community composition was different. Number of spider families increased in field margin but deceased in crop field after harvesting, indicating a migration activity between field and field margin. Vegetation structure in the field margin had different association with carabids than with spiders, with diversity of dominant carabid species positively associated with herb coverage and negatively with wood coverage, while the diversity of spider family Linyphiidae was positively associated with herb coverage only. Semi-natural habitat benefited the conservation of the diversity of arthropod natural enemies in crop field via promoting their dispersal to crop field, while such impacts differed from different vegetation structures and varied from target beneficial natural enemy communities. Future studies should focus on in-depth understanding of the food and habitat source requirement of different natural enemy taxa, and hence to design suitable semi-natural habitats to maintain a high diversity of natural enemy communities.

  11. Editorial. Festschrift on the occasion of Kurt Kremer's 60th birthday

    NASA Astrophysics Data System (ADS)

    Site, Luigi Delle; Deserno, Markus; Dünweg, Burkhard; Holm, Christian; Peter, Christine; Pleiner, Harald

    2016-10-01

    This special topics issue offers a broad perspective on recent theoretical and computational soft matter science, providing state of the art advances in many of its sub-fields. As is befitting for a discipline as diverse as soft matter, the papers collected here span a considerable range of subjects and questions, but they also illustrate numerous connections into both fundamental science and technological/industrial applications, which have accompanied the field since its earliest days. This issue is dedicated to Kurt Kremer, on the occasion of his 60th birthday, honouring his role in establishing this exciting field and consolidating its standing in the frame of current science and technology.

  12. Degeneracy allows for both apparent homogeneity and diversification in populations

    PubMed Central

    Whitacre, James M.; Atamas, Sergei P.

    2013-01-01

    Trait diversity – the substrate for natural selection – is necessary for adaptation through selection, particularly in populations faced with environmental changes that diminish population fitness. In habitats that remain unchanged for many generations, stabilizing selection maximizes exploitation of resources by reducing trait diversity to a narrow optimal range. One might expect that such ostensibly homogeneous populations would have a reduced potential for heritable adaptive responses when faced with fitness-reducing environmental changes. However, field studies have documented populations that, even after long periods of evolutionary stasis, can still rapidly evolve in response to changed environmental conditions. We argue that degeneracy, the ability of diverse population elements to function similarly, can satisfy both the current need to maximize fitness and the future need for diversity. Degenerate ensembles appear functionally redundant in certain environmental contexts and functionally diverse in others. We propose that genetic variation not contributing to the observed range of phenotypes in a current population, also known as cryptic genetic variation (CGV), is a specific case of degeneracy. We argue that CGV, which gradually accumulates in static populations in stable environments, reveals hidden trait differences when environments change. By allowing CGV accumulation, static populations prepare themselves for future rapid adaptations to environmental novelty. A greater appreciation of degeneracy’s role in resolving the inherent tension between current stabilizing selection and future directional selection has implications in conservation biology and may be applied in social and technological systems to maximize current performance while strengthening the potential for future changes. PMID:22910487

  13. Enzymatic Halogenation and Dehalogenation Reactions: Pervasive and Mechanistically Diverse.

    PubMed

    Agarwal, Vinayak; Miles, Zachary D; Winter, Jaclyn M; Eustáquio, Alessandra S; El Gamal, Abrahim A; Moore, Bradley S

    2017-04-26

    Naturally produced halogenated compounds are ubiquitous across all domains of life where they perform a multitude of biological functions and adopt a diversity of chemical structures. Accordingly, a diverse collection of enzyme catalysts to install and remove halogens from organic scaffolds has evolved in nature. Accounting for the different chemical properties of the four halogen atoms (fluorine, chlorine, bromine, and iodine) and the diversity and chemical reactivity of their organic substrates, enzymes performing biosynthetic and degradative halogenation chemistry utilize numerous mechanistic strategies involving oxidation, reduction, and substitution. Biosynthetic halogenation reactions range from simple aromatic substitutions to stereoselective C-H functionalizations on remote carbon centers and can initiate the formation of simple to complex ring structures. Dehalogenating enzymes, on the other hand, are best known for removing halogen atoms from man-made organohalogens, yet also function naturally, albeit rarely, in metabolic pathways. This review details the scope and mechanism of nature's halogenation and dehalogenation enzymatic strategies, highlights gaps in our understanding, and posits where new advances in the field might arise in the near future.

  14. Multiple-locus variable-number tandem repeat analysis of Salmonella Enteritidis isolates from human and non-human sources using a single multiplex PCR

    PubMed Central

    Cho, Seongbeom; Boxrud, David J; Bartkus, Joanne M; Whittam, Thomas S; Saeed, Mahdi

    2007-01-01

    Simplified multiple-locus variable-number tandem repeat analysis (MLVA) was developed using one-shot multiplex PCR for seven variable-number tandem repeats (VNTR) markers with high diversity capacity. MLVA, phage typing, and PFGE methods were applied on 34 diverse Salmonella Enteritidis isolates from human and non-human sources. MLVA detected allelic variations that helped to classify the S. Enteritidis isolates into more evenly distributed subtypes than other methods. MLVA-based S. Enteritidis clonal groups were largely associated with sources of the isolates. Nei's diversity indices for polymorphism ranged from 0.25 to 0.70 for seven VNTR loci markers. Based on Simpson's and Shannon's diversity indices, MLVA had a higher discriminatory power than pulsed field gel electrophoresis (PFGE), phage typing, or multilocus enzyme electrophoresis. Therefore, MLVA may be used along with PFGE to enhance the effectiveness of the molecular epidemiologic investigation of S. Enteritidis infections. PMID:17692097

  15. Application of Unmanned Aircraft System Instrumentation to Study Coastal Geochemistry

    NASA Astrophysics Data System (ADS)

    Coffin, R. B.; Osburn, C. L.; Smith, J. P.

    2016-02-01

    Coastal evaluation of key geochemical cycles is in strong need for thorough spatial data to address diverse topics. In many field studies we find that fixed station data taken from ship operations does not provide complete understanding of key research questions. In complicated systems where there is a need to integrate physical, chemical and biological parameters data taken from research vessels needs to be interpreted across large spatial areas. New technology in Unmanned Aircraft System (UAS) instrumentation coupled with ship board data can provide the thorough spatial data needed for a thorough evaluation of coastal sciences. This presentation will provide field data related to UAS application in two diverse environments. One study focuses on the flux of carbon dioxide and methane from Alaskan Arctic tundra and shallow Beaufort Sea coastal region to the atmosphere. In this study gas chemistry from samples is used to predict the relative fluxes to the atmosphere. A second study applies bio-optical analyses to differentiate between Gulf of Mexico coastal water column DOC and Lignin. This wide range of parameters in diverse ecosystems is selected to show current capability for application of UAS and the potential for understanding large scale questions about climate change and carbon cycling in coastal waters.

  16. High-contrast imaging with the JWST-NIRSpec Integral Field Unit

    NASA Astrophysics Data System (ADS)

    Ygouf, M.; Beichman, C.; Hodapp, K.; Roellig, T.

    2017-12-01

    With its integral field unit, the near-infrared spectrograph NIRSPEC on JWST will allow to measure high-resolution spectra into the 3-\\SI{5}μm range with an increased sensitivity over ground-based systems. This capability will considerably extend our knowledge of brown dwarfs and bright exoplanets at large separations from their host star. But because there is not any coronagraph on NIRSPEC, the performance in term of contrast at close separation will be extremely limited. In this communication, we explore possibilities to further push this limitation by exploiting the wavelength diversity offered by the spectral differential imaging strategy.

  17. Medical color displays and their calibration

    NASA Astrophysics Data System (ADS)

    Fan, Jiahua; Roehrig, Hans; Dallas, W.; Krupinski, Elizabeth

    2009-08-01

    Color displays are increasingly used for medical imaging, replacing the traditional monochrome displays in radiology for multi-modality applications, 3D representation applications, etc. Color displays are also used increasingly because of wide spread application of Tele-Medicine, Tele-Dermatology and Digital Pathology. At this time, there is no concerted effort for calibration procedures for this diverse range of color displays in Telemedicine and in other areas of the medical field. Using a colorimeter to measure the display luminance and chrominance properties as well as some processing software we developed a first attempt to a color calibration protocol for the medical imaging field.

  18. Fungal Communities Including Plant Pathogens in Near Surface Air Are Similar across Northwestern Europe.

    PubMed

    Nicolaisen, Mogens; West, Jonathan S; Sapkota, Rumakanta; Canning, Gail G M; Schoen, Cor; Justesen, Annemarie F

    2017-01-01

    Information on the diversity of fungal spores in air is limited, and also the content of airborne spores of fungal plant pathogens is understudied. In the present study, a total of 152 air samples were taken from rooftops at urban settings in Slagelse, DK, Wageningen NL, and Rothamsted, UK together with 41 samples from above oilseed rape fields in Rothamsted. Samples were taken during 10-day periods in spring and autumn, each sample representing 1 day of sampling. The fungal content of samples was analyzed by metabarcoding of the fungal internal transcribed sequence 1 (ITS1) and by qPCR for specific fungi. The metabarcoding results demonstrated that season had significant effects on airborne fungal communities. In contrast, location did not have strong effects on the communities, even though locations were separated by up to 900 km. Also, a number of plant pathogens had strikingly similar patterns of abundance at the three locations. Rooftop samples were more diverse than samples taken above fields, probably reflecting greater mixing of air from a range of microenvironments for the rooftop sites. Pathogens that were known to be present in the crop were also found in air samples taken above the field. This paper is one of the first detailed studies of fungal composition in air with the focus on plant pathogens and shows that it is possible to detect a range of pathogens in rooftop air samplers using metabarcoding.

  19. Mass spectrometry as a quantitative tool in plant metabolomics

    PubMed Central

    Jorge, Tiago F.; Mata, Ana T.

    2016-01-01

    Metabolomics is a research field used to acquire comprehensive information on the composition of a metabolite pool to provide a functional screen of the cellular state. Studies of the plant metabolome include the analysis of a wide range of chemical species with very diverse physico-chemical properties, and therefore powerful analytical tools are required for the separation, characterization and quantification of this vast compound diversity present in plant matrices. In this review, challenges in the use of mass spectrometry (MS) as a quantitative tool in plant metabolomics experiments are discussed, and important criteria for the development and validation of MS-based analytical methods provided. This article is part of the themed issue ‘Quantitative mass spectrometry’. PMID:27644967

  20. Trail networks formed by populations of immune cells

    NASA Astrophysics Data System (ADS)

    Yang, Taeseok Daniel; Kwon, Tae Goo; Park, Jin-sung; Lee, Kyoung J.

    2014-02-01

    Populations of biological cells that communicate with each other can organize themselves to generate large-scale patterns. Examples can be found in diverse systems, ranging from developing embryos, cardiac tissues, chemotaxing ameba and swirling bacteria. The similarity, often shared by the patterns, suggests the existence of some general governing principle. On the other hand, rich diversity and system-specific properties are exhibited, depending on the type of involved cells and the nature of their interactions. The study on the similarity and the diversity constitutes a rapidly growing field of research. Here, we introduce a new class of self-organized patterns of cell populations that we term as ‘cellular trail networks’. They were observed with populations of rat microglia, the immune cells of the brain and the experimental evidence suggested that haptotaxis is the key element responsible for them. The essential features of the observed patterns are well captured by the mathematical model cells that actively crawl and interact with each other through a decomposing but non-diffusing chemical attractant laid down by the cells. Our finding suggests an unusual mechanism of socially cooperative long-range signaling for the crawling immune cells.

  1. Location Based Application Availability

    NASA Astrophysics Data System (ADS)

    Naeem Akram, Raja; Markantonakis, Konstantinos; Mayes, Keith

    Smart cards are being integrated into a diverse range of industries: ranging from banking, telecom, transport, home/office access control to health and E-passport. Traditionally, cardholders are required to carry a smart card for each application. However, recent developments in the Near Field Communication (NFC) have renewed the interest in multiple applications for different services on a single device. This paper builds onto the NFC initiative and avoids the smart card ownership issues that hinder the adoption of such devices. The proposal integrates the Global Positioning System with the NFC in mobile phones to provide a ubiquitously and flexible service access model.

  2. European Invasion of North American Pinus strobus at Large and Fine Scales: High Genetic Diversity and Fine-Scale Genetic Clustering over Time in the Adventive Range

    PubMed Central

    Mandák, Bohumil; Hadincová, Věroslava; Mahelka, Václav; Wildová, Radka

    2013-01-01

    Background North American Pinus strobus is a highly invasive tree species in Central Europe. Using ten polymorphic microsatellite loci we compared various aspects of the large-scale genetic diversity of individuals from 30 sites in the native distribution range with those from 30 sites in the European adventive distribution range. To investigate the ascertained pattern of genetic diversity of this intercontinental comparison further, we surveyed fine-scale genetic diversity patterns and changes over time within four highly invasive populations in the adventive range. Results Our data show that at the large scale the genetic diversity found within the relatively small adventive range in Central Europe, surprisingly, equals the diversity found within the sampled area in the native range, which is about thirty times larger. Bayesian assignment grouped individuals into two genetic clusters separating North American native populations from the European, non-native populations, without any strong genetic structure shown over either range. In the case of the fine scale, our comparison of genetic diversity parameters among the localities and age classes yielded no evidence of genetic diversity increase over time. We found that SGS differed across age classes within the populations under study. Old trees in general completely lacked any SGS, which increased over time and reached its maximum in the sapling stage. Conclusions Based on (1) the absence of difference in genetic diversity between the native and adventive ranges, together with the lack of structure in the native range, and (2) the lack of any evidence of any temporal increase in genetic diversity at four highly invasive populations in the adventive range, we conclude that population amalgamation probably first happened in the native range, prior to introduction. In such case, there would have been no need for multiple introductions from previously isolated populations, but only several introductions from genetically diverse populations. PMID:23874648

  3. Avian Species and Functional Diversity in Agricultural Landscapes: Does Landscape Heterogeneity Matter?

    PubMed Central

    2017-01-01

    While the positive relationship between avian diversity and habitat heterogeneity is widely accepted, it is primarily based on observed species richness without accounting for imperfect detection. Other facets of diversity such as functional diversity are also rarely explored. We investigated the avian diversity-landscape heterogeneity relationship in agricultural landscapes by considering two aspects of diversity: taxonomic diversity (species richness) estimated from a multi-species dynamic occupancy model, and functional diversity (functional evenness [FEve] and divergence [FDiv]) based on traits of occurring species. We also assessed how agricultural lands enrolled in a conservation program managed on behalf of declining early successional bird species (hereafter CP38 fields, an agri-environment scheme) influenced avian diversity. We analyzed breeding bird data collected at CP38 fields in Mississippi, USA, during 2010–2012, and two principal components of environmental variables: a gradient of heterogeneity (Shannon’s landscape diversity index) and of the amount of CP38 fields (percent cover of CP38 fields; CP38). FEve did not show significant responses to environmental variables, whereas FDiv responded positively to heterogeneity and negatively to CP38. However, most FDiv values did not significantly differ from random expectations along an environmental gradient. When there was a significant difference, FDiv was lower than that expected. Unlike functional diversity, species richness showed a clear pattern. Species richness increased with increasing landscape heterogeneity but decreased with increasing amounts of CP38 fields. Only one species responded negatively to heterogeneity and positively to CP38. Our results suggest that the relationships between avian diversity and landscape heterogeneity may vary depending on the aspect of diversity considered: strong positive effects of heterogeneity on taxonomic diversity, but weakly positive or non-significant effects on functional diversity. Our results also indicate that effectiveness of CP38 in conserving avian diversity, particularly, taxonomic diversity, could be limited without the consideration of landscape heterogeneity. PMID:28125653

  4. Avian Species and Functional Diversity in Agricultural Landscapes: Does Landscape Heterogeneity Matter?

    PubMed

    Lee, Myung-Bok; Martin, James A

    2017-01-01

    While the positive relationship between avian diversity and habitat heterogeneity is widely accepted, it is primarily based on observed species richness without accounting for imperfect detection. Other facets of diversity such as functional diversity are also rarely explored. We investigated the avian diversity-landscape heterogeneity relationship in agricultural landscapes by considering two aspects of diversity: taxonomic diversity (species richness) estimated from a multi-species dynamic occupancy model, and functional diversity (functional evenness [FEve] and divergence [FDiv]) based on traits of occurring species. We also assessed how agricultural lands enrolled in a conservation program managed on behalf of declining early successional bird species (hereafter CP38 fields, an agri-environment scheme) influenced avian diversity. We analyzed breeding bird data collected at CP38 fields in Mississippi, USA, during 2010-2012, and two principal components of environmental variables: a gradient of heterogeneity (Shannon's landscape diversity index) and of the amount of CP38 fields (percent cover of CP38 fields; CP38). FEve did not show significant responses to environmental variables, whereas FDiv responded positively to heterogeneity and negatively to CP38. However, most FDiv values did not significantly differ from random expectations along an environmental gradient. When there was a significant difference, FDiv was lower than that expected. Unlike functional diversity, species richness showed a clear pattern. Species richness increased with increasing landscape heterogeneity but decreased with increasing amounts of CP38 fields. Only one species responded negatively to heterogeneity and positively to CP38. Our results suggest that the relationships between avian diversity and landscape heterogeneity may vary depending on the aspect of diversity considered: strong positive effects of heterogeneity on taxonomic diversity, but weakly positive or non-significant effects on functional diversity. Our results also indicate that effectiveness of CP38 in conserving avian diversity, particularly, taxonomic diversity, could be limited without the consideration of landscape heterogeneity.

  5. Genetic Diversity and Population Structure in a Legacy Collection of Spring Barley Landraces Adapted to a Wide Range of Climates

    PubMed Central

    Walther, Alexander; Özkan, Hakan; Graner, Andreas; Kilian, Benjamin

    2014-01-01

    Global environmental change and increasing human population emphasize the urgent need for higher yielding and better adapted crop plants. One strategy to achieve this aim is to exploit the wealth of so called landraces of crop species, representing diverse traditional domesticated populations of locally adapted genotypes. In this study, we investigated a comprehensive set of 1485 spring barley landraces (Lrc1485) adapted to a wide range of climates, which were selected from one of the largest genebanks worldwide. The landraces originated from 5° to 62.5° N and 16° to 71° E. The whole collection was genotyped using 42 SSR markers to assess the genetic diversity and population structure. With an average allelic richness of 5.74 and 372 alleles, Lrc1485 harbours considerably more genetic diversity than the most polymorphic current GWAS panel for barley. Ten major clusters defined most of the population structure based on geographical origin, row type of the ear and caryopsis type – and were assigned to specific climate zones. The legacy core reference set Lrc648 established in this study will provide a long-lasting resource and a very valuable tool for the scientific community. Lrc648 is best suited for multi-environmental field testing to identify candidate genes underlying quantitative traits but also for allele mining approaches. PMID:25541702

  6. What triggers the rising of an intraspecific biodiversity hotspot? Hints from the agile frog.

    PubMed

    Canestrelli, Daniele; Bisconti, Roberta; Sacco, Florinda; Nascetti, Giuseppe

    2014-05-23

    Hotspots of genetic diversity are regions of utmost importance for species survival and conservation, and their intimate link with the geographic location of glacial refugia has been well established. Nonetheless, the microevolutionary processes underlying the generation of hotspots in such regions have only recently become a fervent field of research. We investigated the phylogeographic and population genetic structure of the agile frog, Rana dalmatina, within its putative refugium in peninsular Italy. We found this region to harbour far more diversity, phylogeographic structure, and lineages of ancient origin than that by the rest of the species' range in Europe. This pattern appeared to be well explained by climate-driven microevolutionary processes that occurred during both glacial and interglacial epochs. Therefore, the inferred evolutionary history of R. dalmatina in Italy supports a view of glacial refugia as 'factories' rather than as repositories of genetic diversity, with significant implications for conservation strategies for hotspots.

  7. Nucleobases, nucleosides, and nucleotides: versatile biomolecules for generating functional nanomaterials.

    PubMed

    Pu, Fang; Ren, Jinsong; Qu, Xiaogang

    2018-02-21

    The incorporation of biomolecules into nanomaterials generates functional nanosystems with novel and advanced properties, presenting great potential for applications in various fields. Nucleobases, nucleosides and nucleotides, as building blocks of nucleic acids and biological coenzymes, constitute necessary components of the foundation of life. In recent years, as versatile biomolecules for the construction or regulation of functional nanomaterials, they have stimulated interest in researchers, due to their unique properties such as structural diversity, multiplex binding sites, self-assembly ability, stability, biocompatibility, and chirality. In this review, strategies for the synthesis of nanomaterials and the regulation of their morphologies and functions using nucleobases, nucleosides, and nucleotides as building blocks, templates or modulators are summarized alongside selected applications. The diverse applications range from sensing, bioimaging, and drug delivery to mimicking light-harvesting antenna, the construction of logic gates, and beyond. Furthermore, some perspectives and challenges in this emerging field are proposed. This review is directed toward the broader scientific community interested in biomolecule-based functional nanomaterials.

  8. Chemical diversity of microbial volatiles and their potential for plant growth and productivity

    PubMed Central

    Kanchiswamy, Chidananda Nagamangala; Malnoy, Mickael; Maffei, Massimo E.

    2015-01-01

    Microbial volatile organic compounds (MVOCs) are produced by a wide array of microorganisms ranging from bacteria to fungi. A growing body of evidence indicates that MVOCs are ecofriendly and can be exploited as a cost-effective sustainable strategy for use in agricultural practice as agents that enhance plant growth, productivity, and disease resistance. As naturally occurring chemicals, MVOCs have potential as possible alternatives to harmful pesticides, fungicides, and bactericides as well as genetic modification. Recent studies performed under open field conditions demonstrate that efficiently adopting MVOCs may contribute to sustainable crop protection and production. We review here the chemical diversity of MVOCs by describing microbial–plants and microbial–microbial interactions. Furthermore, we discuss MVOCs role in inducing phenotypic plant responses and their potential physiological effects on crops. Finally, we analyze potential and actual limitations for MVOC use and deployment in field conditions as a sustainable strategy for improving productivity and reducing pesticide use. PMID:25821453

  9. Mitochondrial DNA Analyses Indicate High Diversity, Expansive Population Growth and High Genetic Connectivity of Vent Copepods (Dirivultidae) across Different Oceans

    PubMed Central

    Kihara, Terue C.; Laurent, Stefan; Kodami, Sahar; Martinez Arbizu, Pedro

    2016-01-01

    Communities in spatially fragmented deep-sea hydrothermal vents rich in polymetallic sulfides could soon face major disturbance events due to deep-sea mineral mining, such that unraveling patterns of gene flow between hydrothermal vent populations will be an important step in the development of conservation policies. Indeed, the time required by deep-sea populations to recover following habitat perturbations depends both on the direction of gene flow and the number of migrants available for re-colonization after disturbance. In this study we compare nine dirivultid copepod species across various geological settings. We analyze partial nucleotide sequences of the mtCOI gene and use divergence estimates (FST) and haplotype networks to infer intraspecific population connectivity between vent sites. Furthermore, we evaluate contrasting scenarios of demographic population expansion/decline versus constant population size (using, for example, Tajima’s D). Our results indicate high diversity, population expansion and high connectivity of all copepod populations in all oceans. For example, haplotype diversity values range from 0.89 to 1 and FST values range from 0.001 to 0.11 for Stygiopontius species from the Central Indian Ridge, Mid Atlantic Ridge, East Pacific Rise, and Eastern Lau Spreading Center. We suggest that great abundance and high site occupancy by these species favor high genetic diversity. Two scenarios both showed similarly high connectivity: fast spreading centers with little distance between vent fields and slow spreading centers with greater distance between fields. This unexpected result may be due to some distinct frequency of natural disturbance events, or to aspects of individual life histories that affect realized rates of dispersal. However, our statistical performance analyses showed that at least 100 genomic regions should be sequenced to ensure accurate estimates of migration rate. Our demography parameters demonstrate that dirivultid populations are generally large and continuously undergoing population growth. Benthic and pelagic species abundance data support these findings. PMID:27732624

  10. Detecting in situ copepod diet diversity using molecular technique: development of a copepod/symbiotic ciliate-excluding eukaryote-inclusive PCR protocol.

    PubMed

    Hu, Simin; Guo, Zhiling; Li, Tao; Carpenter, Edward J; Liu, Sheng; Lin, Senjie

    2014-01-01

    Knowledge of in situ copepod diet diversity is crucial for accurately describing pelagic food web structure but is challenging to achieve due to lack of an easily applicable methodology. To enable analysis with whole copepod-derived DNAs, we developed a copepod-excluding 18S rDNA-based PCR protocol. Although it is effective in depressing amplification of copepod 18S rDNA, its applicability to detect diverse eukaryotes in both mono- and mixed-species has not been demonstrated. Besides, the protocol suffers from the problem that sequences from symbiotic ciliates are overrepresented in the retrieved 18S rDNA libraries. In this study, we designed a blocking primer to make a combined primer set (copepod/symbiotic ciliate-excluding eukaryote-common: CEEC) to depress PCR amplification of symbiotic ciliate sequences while maximizing the range of eukaryotes amplified. We firstly examined the specificity and efficacy of CEEC by PCR-amplifying DNAs from 16 copepod species, 37 representative organisms that are potential prey of copepods and a natural microplankton sample, and then evaluated the efficiency in reconstructing diet composition by detecting the food of both lab-reared and field-collected copepods. Our results showed that the CEEC primer set can successfully amplify 18S rDNA from a wide range of isolated species and mixed-species samples while depressing amplification of that from copepod and targeted symbiotic ciliate, indicating the universality of CEEC in specifically detecting prey of copepods. All the predetermined food offered to copepods in the laboratory were successfully retrieved, suggesting that the CEEC-based protocol can accurately reconstruct the diets of copepods without interference of copepods and their associated ciliates present in the DNA samples. Our initial application to analyzing the food composition of field-collected copepods uncovered diverse prey species, including those currently known, and those that are unsuspected, as copepod prey. While testing is required, this protocol provides a useful strategy for depicting in situ dietary composition of copepods.

  11. Mitochondrial DNA Analyses Indicate High Diversity, Expansive Population Growth and High Genetic Connectivity of Vent Copepods (Dirivultidae) across Different Oceans.

    PubMed

    Gollner, Sabine; Stuckas, Heiko; Kihara, Terue C; Laurent, Stefan; Kodami, Sahar; Martinez Arbizu, Pedro

    2016-01-01

    Communities in spatially fragmented deep-sea hydrothermal vents rich in polymetallic sulfides could soon face major disturbance events due to deep-sea mineral mining, such that unraveling patterns of gene flow between hydrothermal vent populations will be an important step in the development of conservation policies. Indeed, the time required by deep-sea populations to recover following habitat perturbations depends both on the direction of gene flow and the number of migrants available for re-colonization after disturbance. In this study we compare nine dirivultid copepod species across various geological settings. We analyze partial nucleotide sequences of the mtCOI gene and use divergence estimates (FST) and haplotype networks to infer intraspecific population connectivity between vent sites. Furthermore, we evaluate contrasting scenarios of demographic population expansion/decline versus constant population size (using, for example, Tajima's D). Our results indicate high diversity, population expansion and high connectivity of all copepod populations in all oceans. For example, haplotype diversity values range from 0.89 to 1 and FST values range from 0.001 to 0.11 for Stygiopontius species from the Central Indian Ridge, Mid Atlantic Ridge, East Pacific Rise, and Eastern Lau Spreading Center. We suggest that great abundance and high site occupancy by these species favor high genetic diversity. Two scenarios both showed similarly high connectivity: fast spreading centers with little distance between vent fields and slow spreading centers with greater distance between fields. This unexpected result may be due to some distinct frequency of natural disturbance events, or to aspects of individual life histories that affect realized rates of dispersal. However, our statistical performance analyses showed that at least 100 genomic regions should be sequenced to ensure accurate estimates of migration rate. Our demography parameters demonstrate that dirivultid populations are generally large and continuously undergoing population growth. Benthic and pelagic species abundance data support these findings.

  12. Functional supramolecular polymers for biomedical applications.

    PubMed

    Dong, Ruijiao; Zhou, Yongfeng; Huang, Xiaohua; Zhu, Xinyuan; Lu, Yunfeng; Shen, Jian

    2015-01-21

    As a novel class of dynamic and non-covalent polymers, supramolecular polymers not only display specific structural and physicochemical properties, but also have the ability to undergo reversible changes of structure, shape, and function in response to diverse external stimuli, making them promising candidates for widespread applications ranging from academic research to industrial fields. By an elegant combination of dynamic/reversible structures with exceptional functions, functional supramolecular polymers are attracting increasing attention in various fields. In particular, functional supramolecular polymers offer several unique advantages, including inherent degradable polymer backbones, smart responsiveness to various biological stimuli, and the ease for the incorporation of multiple biofunctionalities (e.g., targeting and bioactivity), thereby showing great potential for a wide range of applications in the biomedical field. In this Review, the trends and representative achievements in the design and synthesis of supramolecular polymers with specific functions are summarized, as well as their wide-ranging biomedical applications such as drug delivery, gene transfection, protein delivery, bio-imaging and diagnosis, tissue engineering, and biomimetic chemistry. These achievements further inspire persistent efforts in an emerging interdisciplin-ary research area of supramolecular chemistry, polymer science, material science, biomedical engineering, and nanotechnology. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Beta diversity at different spatial scales: plant communities in organic and conventional agriculture.

    PubMed

    Gabriel, Doreen; Roschewitz, Indra; Tscharntke, Teja; Thies, Carsten

    2006-10-01

    Biodiversity studies that guide agricultural subsidy policy have generally compared farming systems at a single spatial scale: the field. However, diversity patterns vary across spatial scales. Here, we examined the effects of farming system (organic vs. conventional) and position in the field (edge vs. center) on plant species richness in wheat fields at three spatial scales. We quantified alpha-, beta-, and gamma-diversity at the microscale in 800 plots, at the mesoscale in 40 fields, and at the macroscale in three regions using the additive partitioning approach, and evaluated the relative contribution of beta-diversity at each spatial scale to total observed species richness. We found that alpha-, beta-, and gamma-diversity were higher in organic than conventional fields and higher at the field edge than in the field center at all spatial scales. In both farming systems, beta-diversity at the meso- and macroscale explained most of the overall species richness (up to 37% and 25%, respectively), indicating considerable differences in community composition among fields and regions due to environmental heterogeneity. The spatial scale at which beta-diversity contributed the most to overall species richness differed between rare and common species. Total richness of rare species (present in < or = 5% of total samples) was mainly explained by differences in community composition at the meso- and macroscale (up to 27% and 48%, respectively), but only in organic fields. Total richness of common species (present in > or = 25% of total samples) was explained by differences in community composition at the micro- and mesoscale (up to 29% and 47%, respectively), i.e., among plots and fields, independent of farming system. Our results show that organic farming made the greatest contribution to total species richness at the meso (among fields) and macro (among regions) scale due to environmental heterogeneity. Hence, agri-environment schemes should exploit this large-scale contribution of beta-diversity by tailoring schemes at regional scales to maximize dissimilarity between conservation areas using geographic information systems rather than focusing entirely at the classical local-field scale, which is the current practice.

  14. Degeneracy allows for both apparent homogeneity and diversification in populations.

    PubMed

    Whitacre, James M; Atamas, Sergei P

    2012-10-01

    Trait diversity - the substrate for natural selection - is necessary for adaptation through selection, particularly in populations faced with environmental changes that diminish population fitness. In habitats that remain unchanged for many generations, stabilizing selection maximizes exploitation of resources by reducing trait diversity to a narrow optimal range. One might expect that such ostensibly homogeneous populations would have a reduced potential for heritable adaptive responses when faced with fitness-reducing environmental changes. However, field studies have documented populations that, even after long periods of evolutionary stasis, can still rapidly evolve in response to changed environmental conditions. We argue that degeneracy, the ability of diverse population elements to function similarly, can satisfy both the current need to maximize fitness and the future need for diversity. Degenerate ensembles appear functionally redundant in certain environmental contexts and functionally diverse in others. We propose that genetic variation not contributing to the observed range of phenotypes in a current population, also known as cryptic genetic variation (CGV), is a specific case of degeneracy. We argue that CGV, which gradually accumulates in static populations in stable environments, reveals hidden trait differences when environments change. By allowing CGV accumulation, static populations prepare themselves for future rapid adaptations to environmental novelty. A greater appreciation of degeneracy's role in resolving the inherent tension between current stabilizing selection and future directional selection has implications in conservation biology and may be applied in social and technological systems to maximize current performance while strengthening the potential for future changes. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  15. Emergent magnetic anisotropy in the cubic heavy-fermion metal CeIn3

    DOE PAGES

    Moll, Philip J. W.; Helm, Toni; Zhang, Shang-Shun; ...

    2017-08-21

    Metals containing cerium exhibit a diverse range of fascinating phenomena including heavy fermion behavior, quantum criticality, and novel states of matter such as unconventional superconductivity. The cubic system CeIn3 has attracted significant attention as a structurally isotropic Kondo lattice material possessing the minimum required complexity to still reveal this rich physics. By using magnetic fields with strengths comparable to the crystal field energy scale, we illustrate a strong field-induced anisotropy as a consequence of non-spherically symmetric spin interactions in the prototypical heavy fermion material CeIn3. We demonstrate the importance of magnetic anisotropy in modeling f-electron materials when the orbital charactermore » of the 4f wavefunction changes (e.g., with pressure or composition). Additionally, magnetic fields are shown to tune the effective hybridization and exchange interactions potentially leading to new exotic field tuned effects in f-based materials.« less

  16. Emergent magnetic anisotropy in the cubic heavy-fermion metal CeIn3

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moll, Philip J. W.; Helm, Toni; Zhang, Shang-Shun

    Metals containing cerium exhibit a diverse range of fascinating phenomena including heavy fermion behavior, quantum criticality, and novel states of matter such as unconventional superconductivity. The cubic system CeIn3 has attracted significant attention as a structurally isotropic Kondo lattice material possessing the minimum required complexity to still reveal this rich physics. By using magnetic fields with strengths comparable to the crystal field energy scale, we illustrate a strong field-induced anisotropy as a consequence of non-spherically symmetric spin interactions in the prototypical heavy fermion material CeIn3. We demonstrate the importance of magnetic anisotropy in modeling f-electron materials when the orbital charactermore » of the 4f wavefunction changes (e.g., with pressure or composition). Additionally, magnetic fields are shown to tune the effective hybridization and exchange interactions potentially leading to new exotic field tuned effects in f-based materials.« less

  17. PARPs and ADP-Ribosylation: 50 Years … and Counting.

    PubMed

    Kraus, W Lee

    2015-06-18

    Over 50 years ago, the discovery of poly(ADP-ribose) (PAR) set a new field of science in motion-the field of poly(ADP-ribosyl) transferases (PARPs) and ADP-ribosylation. The field is still flourishing today. The diversity of biological processes now known to require PARPs and ADP-ribosylation was practically unimaginable even two decades ago. From an initial focus on DNA damage detection and repair in response to genotoxic stresses, the field has expanded to include the regulation of chromatin structure, gene expression, and RNA processing in a wide range of biological systems, including reproduction, development, aging, stem cells, inflammation, metabolism, and cancer. This special focus issue of Molecular Cell includes a collection of three Reviews, three Perspectives, and a SnapShot, which together summarize the current state of the field and suggest where it may be headed. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Somerville, Chris

    Summer Lecture Series 2007: Chris Somerville, Director of the Energy Biosciences Institute and an award-winning plant biochemist with Berkeley Lab's Physical Biosciences Division, is a leading authority on the structure and function of plant cell walls. He discusses an overview of some of the technical challenges associated with the production of cellulosic biofuels, which will require an improved understanding of a diverse range of topics in fields such as agronomy, chemical engineering, microbiology, structural biology, genomics, environmental sciences, and socioeconomics.

  19. Using Field and Satellite Measurements to Improve Snow and Riming Processes in Cloud Resolving Models

    NASA Technical Reports Server (NTRS)

    Colle, Brian A.; Molthan, Andrew L.

    2013-01-01

    The representation of clouds in climate and weather models is a driver in forecast uncertainty. Cloud microphysics parameterizations are challenged by having to represent a diverse range of ice species. Key characteristics of predicted ice species include habit and fall speed, and complex interactions that result from mixed-phased processes like riming. Our proposed activity leverages Global Precipitation Measurement (GPM) Mission ground validation studies to improve parameterizations

  20. Design of virus-based nanomaterials for medicine, biotechnology, and energy

    PubMed Central

    Wen, Amy M.; Steinmetz, Nicole F.

    2016-01-01

    Virus-based nanomaterials are versatile materials that naturally self-assemble and have relevance for a broad range of applications including medicine, biotechnology, and energy. This review provides an overview of recent developments in “chemical virology.” Viruses, as materials, provide unique nanoscale scaffolds that have relevance in chemical biology and nanotechnology, with diverse areas of applications. Some fundamental advantages of viruses, compared to synthetically programmed materials, include the highly precise spatial arrangement of their subunits into a diverse array of shapes and sizes and many available avenues for easy and reproducible modification. Here, we will first survey the broad distribution of viruses and various methods for producing virus-based nanoparticles, as well as engineering principles used to impart new functionalities. We will then examine the broad range of applications and implications of virus-based materials, focusing on the medical, biotechnology, and energy sectors. We anticipate that this field will continue to evolve and grow, with exciting new possibilities stemming from advancements in the rational design of virus-based nanomaterials. PMID:27152673

  1. Resolving the substructure of molecular clouds in the LMC

    NASA Astrophysics Data System (ADS)

    Wong, Tony; Hughes, Annie; Tokuda, Kazuki; Indebetouw, Remy; Wojciechowski, Evan; Bandurski, Jeffrey; MC3 Collaboration

    2018-01-01

    We present recent wide-field CO and 13CO mapping of giant molecular clouds in the Large Magellanic Cloud with ALMA. Our sample exhibits diverse star-formation properties, and reveals comparably diverse molecular cloud properties including surface density and velocity dispersion at a given scale. We first present the results of a recent study comparing two GMCs at the extreme ends of the star formation activity spectrum. Our quiescent cloud exhibits 10 times lower surface density and 5 times lower velocity dispersion than the active 30 Doradus cloud, yet in both clouds we find a wide range of line widths at the smallest resolved scales, spanning nearly the full range of line widths seen at all scales. This suggests an important role for feedback on sub-parsec scales, while the energetics on larger scales are dominated by clump-to-clump relative velocities. We then extend our analysis to four additional clouds that exhibit intermediate levels of star formation activity.

  2. Rangewide genetic analysis of Lesser Prairie-Chicken reveals population structure, range expansion, and possible introgression

    USGS Publications Warehouse

    Oyler-McCance, Sara J.; DeYoung, Randall W; Fike, Jennifer; Hagen, Christian A.; Johnson, Jeff A.; Larsson, Lena C.; Patten, Michael

    2016-01-01

    The distribution of the Lesser Prairie-Chicken (Tympanuchus pallidicinctus) has been markedly reduced due to loss and fragmentation of habitat. Portions of the historical range, however, have been recolonized and even expanded due to planting of conservation reserve program (CRP) fields that provide favorable vegetation structure for Lesser Prairie-Chickens. The source population(s) feeding the range expansion is unknown, yet has resulted in overlap between Lesser and Greater Prairie-Chickens (T. cupido) increasing the potential for hybridization. Our objectives were to characterize connectivity and genetic diversity among populations, identify source population(s) of recent range expansion, and examine hybridization with the Greater Prairie-Chicken. We analyzed 640 samples from across the range using 13 microsatellites. We identified three to four populations corresponding largely to ecoregions. The Shinnery Oak Prairie and Sand Sagebrush Prairie represented genetically distinct populations (F ST > 0.034 and F ST > 0.023 respectively). The Shortgrass/CRP Mosaic and Mixed Grass ecoregions appeared admixed (F ST = 0.009). Genetic diversity was similar among ecoregions and N e ranged from 142 (95 % CI 99–236) for the Shortgrass/CRP Mosaic to 296 (95 % CI 233–396) in the Mixed Grass Prairie. No recent migration was detected among ecoregions, except asymmetric dispersal from both the Mixed Grass Prairie and to a lesser extent the Sand Sagebrush Prairie north into adjacent Shortgrass/CRP Mosaic (m = 0.207, 95 % CI 0.116–0.298, m = 0.097, 95 % CI 0.010–0.183, respectively). Indices investigating potential hybridization in the Shortgrass/CRP Mosaic revealed that six of the 13 individuals with hybrid phenotypes were significantly admixed suggesting hybridization. Continued monitoring of diversity within and among ecoregions is warranted as are actions promoting genetic connectivity and range expansion.

  3. Direct vs. Microclimate-Driven Effects of Tree Species Diversity on Litter Decomposition in Young Subtropical Forest Stands.

    PubMed

    Seidelmann, Katrin N; Scherer-Lorenzen, Michael; Niklaus, Pascal A

    2016-01-01

    Effects of tree species diversity on decomposition can operate via a multitude of mechanism, including alterations of microclimate by the forest canopy. Studying such effects in natural settings is complicated by the fact that topography also affects microclimate and thus decomposition, so that effects of diversity are more difficult to isolate. Here, we quantified decomposition rates of standard litter in young subtropical forest stands, separating effects of canopy tree species richness and topography, and quantifying their direct and micro-climate-mediated components. Our litterbag study was carried out at two experimental sites of a biodiversity-ecosystem functioning field experiment in south-east China (BEF-China). The field sites display strong topographical heterogeneity and were planted with tree communities ranging from monocultures to mixtures of 24 native subtropical tree species. Litter bags filled with senescent leaves of three native tree species were placed from Nov. 2011 to Oct. 2012 on 134 plots along the tree species diversity gradient. Topographic features were measured for all and microclimate in a subset of plots. Stand species richness, topography and microclimate explained important fractions of the variations in litter decomposition rates, with diversity and topographic effects in part mediated by microclimatic changes. Tree stands were 2-3 years old, but nevertheless tree species diversity explained more variation (54.3%) in decomposition than topography (7.7%). Tree species richness slowed litter decomposition, an effect that slightly depended on litter species identity. A large part of the variance in decomposition was explained by tree species composition, with the presence of three tree species playing a significant role. Microclimate explained 31.4% of the variance in decomposition, and was related to lower soil moisture. Within this microclimate effect, species diversity (without composition) explained 8.9% and topography 34.4% of variance. Topography mainly affected diurnal temperature amplitudes by varying incident solar radiation.

  4. Direct vs. Microclimate-Driven Effects of Tree Species Diversity on Litter Decomposition in Young Subtropical Forest Stands

    PubMed Central

    Seidelmann, Katrin N.; Scherer-Lorenzen, Michael; Niklaus, Pascal A.

    2016-01-01

    Effects of tree species diversity on decomposition can operate via a multitude of mechanism, including alterations of microclimate by the forest canopy. Studying such effects in natural settings is complicated by the fact that topography also affects microclimate and thus decomposition, so that effects of diversity are more difficult to isolate. Here, we quantified decomposition rates of standard litter in young subtropical forest stands, separating effects of canopy tree species richness and topography, and quantifying their direct and micro-climate-mediated components. Our litterbag study was carried out at two experimental sites of a biodiversity-ecosystem functioning field experiment in south-east China (BEF-China). The field sites display strong topographical heterogeneity and were planted with tree communities ranging from monocultures to mixtures of 24 native subtropical tree species. Litter bags filled with senescent leaves of three native tree species were placed from Nov. 2011 to Oct. 2012 on 134 plots along the tree species diversity gradient. Topographic features were measured for all and microclimate in a subset of plots. Stand species richness, topography and microclimate explained important fractions of the variations in litter decomposition rates, with diversity and topographic effects in part mediated by microclimatic changes. Tree stands were 2–3 years old, but nevertheless tree species diversity explained more variation (54.3%) in decomposition than topography (7.7%). Tree species richness slowed litter decomposition, an effect that slightly depended on litter species identity. A large part of the variance in decomposition was explained by tree species composition, with the presence of three tree species playing a significant role. Microclimate explained 31.4% of the variance in decomposition, and was related to lower soil moisture. Within this microclimate effect, species diversity (without composition) explained 8.9% and topography 34.4% of variance. Topography mainly affected diurnal temperature amplitudes by varying incident solar radiation. PMID:27490180

  5. Achieving consistent color and grayscale presentation on medial color displays

    NASA Astrophysics Data System (ADS)

    Fan, Jiahua; Roehrig, Hans; Dallas, William; Krupinski, Elizabeth A.

    2008-03-01

    Color displays are increasingly used for medical imaging, replacing the traditional monochrome displays in radiology for multi-modality applications, 3D representation applications, etc. Color displays are also used increasingly because of wide spread application of Tele-Medicine, Tele-Dermatology and Digital Pathology. At this time, there is no concerted effort for calibration procedures for this diverse range of color displays in Telemedicine and in other areas of the medical field. Using a colorimeter to measure the display luminance and chrominance properties as well as some processing software we developed a first attempt to a color calibration protocol for the medical imaging field.

  6. Mixing effects on litter decomposition rates in a young tree diversity experiment

    NASA Astrophysics Data System (ADS)

    Setiawan, Nuri Nurlaila; Vanhellemont, Margot; De Schrijver, An; Schelfhout, Stephanie; Baeten, Lander; Verheyen, Kris

    2016-01-01

    Litter decomposition is an essential process for biogeochemical cycling and for the formation of new soil organic matter. Mixing litter from different tree species has been reported to increase litter decomposition rates through synergistic effects. We assessed the decomposition rates of leaf litter from five tree species in a recently established tree diversity experiment on a post-agriculture site in Belgium. We used 20 different leaf litter compositions with diversity levels ranging from 1 up to 4 species. Litter mass loss in litterbags was assessed 10, 20, 25, 35, and 60 weeks after installation in the field. We found that litter decomposition rates were higher for high-quality litters, i.e., with high nitrogen content and low lignin content. The decomposition rates of mixed litter were more affected by the identity of the litter species within the mixture than by the diversity of the litter per se, but the variability in litter decomposition rates decreased as the litter diversity increased. Among the 15 different mixed litter compositions in our study, only three litter combinations showed synergistic effects. Our study suggests that admixing tree species with high-quality litter in post-agricultural plantations helps in increasing the mixture's early-stage litter decomposition rate.

  7. Diversification of school psychology: Developing an evidence base from current research and practice.

    PubMed

    Blake, Jamilia J; Graves, Scott; Newell, Markeda; Jimerson, Shane R

    2016-09-01

    Why is there a need to increase the racial/ethnic diversity of faculty in school psychology? Chiefly, school psychologists serve the most racially/ethnically diverse population: children in US schools. Therefore, developing a knowledge base that is inclusive of this wide range of perspective as well as growing a workforce that is reflective of this diversity is essential to effective service delivery. To achieve this goal, school psychology trainers must develop evidence-based, purposeful efforts to recruit and retain racial/ethnic minority students in doctoral programs. For these reasons, we called for a special issue on diversifying the field of school psychology. The purpose of this special issue is to advance the evidence-base in school psychology on how to increase diverse scholars and leaders in the profession. Moreover, the goal is to also evaluate the status of the profession in effectively recruiting and retaining racial/ethnic minority graduate students, mentoring racial/ethnic minority students to pursue careers in academia, and promoting faculty development and retention of racially and ethnically diverse faculty. Thus, the articles in this special issue will address critical areas where trainers can improve recruitment and retention strategies that will increase the racial/ethnic diversity of school psychology faculty, leaders, and practitioners. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  8. Genetic Structure and Potential Environmental Determinants of Local Genetic Diversity in Japanese Honeybees (Apis cerana japonica)

    PubMed Central

    Nagamitsu, Teruyoshi; Yasuda, Mika; Saito-Morooka, Fuki; Inoue, Maki N.; Nishiyama, Mio; Goka, Koichi; Sugiura, Shinji; Maeto, Kaoru; Okabe, Kimiko; Taki, Hisatomo

    2016-01-01

    Declines in honeybee populations have been a recent concern. Although causes of the declines remain unclear, environmental factors may be responsible. We focused on the potential environmental determinants of local populations of wild honeybees, Apis cerana japonica, in Japan. This subspecies has little genetic variation in terms of its mitochondrial DNA sequences, and genetic variations at nuclear loci are as yet unknown. We estimated the genetic structure and environmental determinants of local genetic diversity in nuclear microsatellite genotypes of fathers and mothers, inferred from workers collected at 139 sites. The genotypes of fathers and mothers showed weak isolation by distance and negligible genetic structure. The local genetic diversity was high in central Japan, decreasing toward the peripheries, and depended on the climate and land use characteristics of the sites. The local genetic diversity decreased as the annual precipitation increased, and increased as the proportion of urban and paddy field areas increased. Positive effects of natural forest area, which have also been observed in terms of forager abundance in farms, were not detected with respect to the local genetic diversity. The findings suggest that A. cerana japonica forms a single population connected by gene flow in its main distributional range, and that climate and landscape properties potentially affect its local genetic diversity. PMID:27898704

  9. Tucson Diversion Channel. Phase I. Sport Fields & Picnic Area. Feature Design Memorandum Number 3.

    DTIC Science & Technology

    1983-04-01

    opportunities for picnicking, a variety of field sports and court games , archery, jogging, and bicycling. d. Rapid urban growth in the Tucson metropolitan area...AD’A136 927 TUCSON DIVERSION CHANNEL PHASE I SPORT FIELDS A PICNI IC J AREA FEATURE DESIGN MEMORANDUM NUMBER 3(U) ARMY ENGINEER DISTRICT LOS ANGELES...TUCSON DIVERSION CHMNEL DESIGN EIORANDUK NO. 3 FEATURE DESIGN MNRORANDIJ PHASE I SPORT FIELDS & PICNIC AREA APRIL 1983 t1 US AM CORPS OF

  10. Diversity and Distribution of Thermophilic Bacteria in Hot Springs of Pakistan.

    PubMed

    Amin, Arshia; Ahmed, Iftikhar; Salam, Nimaichand; Kim, Byung-Yong; Singh, Dharmesh; Zhi, Xiao-Yang; Xiao, Min; Li, Wen-Jun

    2017-07-01

    Chilas and Hunza areas, located in the Main Mantle Thrust and Main Karakoram Thrust of the Himalayas, host a range of geochemically diverse hot springs. This Himalayan geothermal region encompassed hot springs ranging in temperature from 60 to 95 °C, in pH from 6.2 to 9.4, and in mineralogy from bicarbonates (Tato Field), sulfates (Tatta Pani) to mixed type (Murtazaabad). Microbial community structures in these geothermal springs remained largely unexplored to date. In this study, we report a comprehensive, culture-independent survey of microbial communities in nine samples from these geothermal fields by employing a bar-coded pyrosequencing technique. The bacterial phyla Proteobacteria and Chloroflexi were dominant in all samples from Tato Field, Tatta Pani, and Murtazaabad. The community structures however depended on temperature, pH, and physicochemical parameters of the geothermal sites. The Murtazaabad hot springs with relatively higher temperature (90-95 °C) favored the growth of phylum Thermotogae, whereas the Tatta Pani thermal spring site TP-H3-b (60 °C) favored the phylum Proteobacteria. At sites with low silica and high temperature, OTUs belonging to phylum Chloroflexi were dominant. Deep water areas of the Murtazaabad hot springs favored the sulfur-reducing bacteria. About 40% of the total OTUs obtained from these samples were unclassified or uncharacterized, suggesting the presence of many undiscovered and unexplored microbiota. This study has provided novel insights into the nature of ecological interactions among important taxa in these communities, which in turn will help in determining future study courses in these sites.

  11. Genotypic diversity effects on the performance of Taraxacum officinale populations increase with time and environmental favorability.

    PubMed

    Drummond, Emily B M; Vellend, Mark

    2012-01-01

    Within-population genetic diversity influences many ecological processes, but few studies have examined how environmental conditions may impact these short-term diversity effects. Over four growing seasons, we followed experimental populations of a clonal, ubiquitous weed, Taraxacum officinale, with different numbers of genotypes in relatively favorable fallow field and unfavorable mowed lawn environmental treatments. Population performance (measured as total leaf area, seed production or biomass) clearly and consistently increased with diversity, and this effect became stronger over the course of the experiment. Diversity effects were stronger, and with different underlying mechanisms, in the fallow field versus the mowed lawn. Large genotypes dominated in the fallow field driving overyielding (via positive selection effects), whereas in the mowed lawn, where performance was limited by regular disturbance, there was evidence for complementarity among genotypes (with one compact genotype in particular performing better in mixture than monoculture). Hence, we predict stronger genotypic diversity effects in environments where intense intraspecific competition enhances genotypic differences. Our four-year field experiment plus seedling establishment trials indicate that genotypic diversity effects have far-reaching and context-dependent consequences across generations.

  12. Diversity in a Hidden Community: Tardiagrades in Lichens.

    ERIC Educational Resources Information Center

    Shofner, Marcia; Vodopich, Darrell

    1993-01-01

    Describes an interesting field experiment examining the distribution and diversity of a single community using lichens and the animals living in them. Combining field experience and laboratory work reveals not only the biology of some unusual organisms, but also community ecology and diversity. (PR)

  13. Ecologic and Morphologic Analysis of a Proposed Network of Sediment Diversions

    NASA Astrophysics Data System (ADS)

    Meselhe, E. A.; Sadid, K. M.; Jung, H.; Messina, F.; Esposito, C.; Liang, M.

    2017-12-01

    Deltaic processes are governed by factors including the characteristics of inflowing sediment (e.g., temporal variability of the load and size class distribution), receiving basins (e.g., water depth, tidal range, circulation pattern, and wind field), and substrate (e.g., sediment type and soil strength). These factors influence the deltaic growth as well as the size and pattern of channel bifurcations. This topic is of importance to deltas experiencing land loss due to subsidence and sea level rise. The Mississippi River Delta is an example where a number of sediment diversions are being considered in conjunction with other restoration actions to minimize loss of wetlands. Historically, the Mississippi River played a significant role in providing sediment, nutrients, and fresh water to support Louisiana's coastal wetland system. As such, a systems perspective for regional-scale implementation of diversions is important. Field observations coupled with numerical modeling at various temporal and spatial scales, has provided insights toward a system-scale approach to design, evaluate and operate sediment diversions. These research activities investigate the uncertainties associated with morphodynamic processes both on the river and receiving basin sides and identify parameters influencing the magnitude and rate of building new land and sustaining existing wetland areas. Specifically, this presentation discusses the impact of extracting sediment and water from fluvial rivers, the ability to convey (and retain) sediment to the receiving basins. In addition to delivering sediment to receiving basins, some proposed sediment diversions could discharge high volumes of nutrient-rich fresh water into existing wetlands and bays. A goal of the analysis presented here is to improve our understanding of morphodynamic responses of the receiving basins and the ecosystem effects of discharges of freshwater and nutrients at this scale.

  14. The geological heritage of the Kurkur-Dungul area in southern Egypt

    NASA Astrophysics Data System (ADS)

    Sallam, Emad S.; Ponedelnik, Alena A.; Tiess, Günter; Yashalova, Natalia N.; Ruban, Dmitry A.

    2018-01-01

    The inventory of the geological heritage of Egypt is important for its efficient conservation and usage for the purposes of science, education, and tourism. The field investigations in the Kurkur-Dungul area in southern Egypt have permitted to identify several unique geological features. Their type, rank, relative abundance, and intrinsic diversity, as well as importance of the entire geological heritage of the study area are investigated. Seven geological heritage types are distinguished, namely stratigraphical, sedimentary, palaeogeographical, mineralogical, structural, geomorphological, and economical types. The rank of the features belonging to the listed types ranges from local to global, and the relative abundance and the intrinsic diversity range from low to high. The global rank is established for the sedimentary type, which is determined by the wide distribution of palaeospring tufa deposits. The high relative abundance and intrinsic diversity are established for the geomorphological type. The entire geological heritage of the Kurkur-Dungul area can be employed for diversification of the existing tourism programs offered at the tourist destination of Aswan, as well as for geotourism development. A geopark can be created in the Kurkur-Dungul area for the better exploitation of its geological heritage. The combined development of geological and industrial tourism seems to be possible.

  15. Massachusetts Institute of Technology Consortium Agreement

    DTIC Science & Technology

    1999-03-01

    In this, our second progress report of the Phase Two Home Automation and Healthcare Consortium at the Brit and Alex d’Arbeloff Laboratory for...Covered here are the diverse fields of home automation and healthcare research, ranging from human modeling, patient monitoring, and diagnosis to new...sensors and actuators, physical aids, human-machine interface and home automation infrastructure. These results will be presented at the upcoming General Assembly of the Consortium held on October 27-October 30, 1998 at MIT.

  16. Geochemistry and origin of regional dolomites

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hanson, G.N.; Meyers, W.J.

    1991-01-01

    This grant supports the geochemical aspects of the research directed by Profs. W.J. Meyers and G.N. Hanson on the origins of regional dolomites. The field aspects and the stipend for most of the graduate students is provided by donations from oil companies and by grants from NSF and ACS-PRF. Eleven graduate students are involved in dolomite projects allowing diverse range of studies. Each student's results provide new insights to the others which invigorates all of the studies.

  17. Fabryq: Using Phones as Smart Proxies to Control Wearable Devices from the Web

    DTIC Science & Technology

    2014-06-12

    energy efficient, embedded low power device with a short range radio; 2) a user’s mobile phone, which shows a user interface but also acts as a router...ically relays information to a companion application running on the user’s mobile phone (or PC), which in turn communi- cates with servers that the...skills in several diverse fields. Thus, experimentation in deploy- able, mobile wearable devices is largely reserved to experts, and implementation cycles

  18. Thermal Investigations of Nanoaluminum/Perfluoropolyether Core-Shell Impregnated Composites for Structural Energetics

    DTIC Science & Technology

    2014-07-19

    that undergo an oxidation reduction thermite reaction releasing energy. Advances in the field have generated diverse material platforms ranging from bulk...This is a pre ignition reaction (PIR) similar to the one observed by Pantoya and Dean in n Al/Teflon thermite based reactions [14]. PIR exotherms were...2010) 2560–2569. [5] S. Yan, G. Jian, M.R. Zachariah, Electrospun nanofiber-based thermite textiles and their reactive properties, ACS Appl. Mater

  19. 2012 Gordon Research Conference on Bioinspired Materials - Formal Schedule and Speaker/Poster Program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chilkoti, Ashutosk

    2012-06-29

    The emerging, interdisciplinary field of Bioinspired Materials focuses on developing a fundamental understanding of the synthesis, directed self-assembly and hierarchical organization of natural occurring materials, and uses this understanding to engineer new bioinspired artificial materials for diverse applications. The inaugural 2012 Gordon Conference on Bioinspired Materials seeks to capture the excitement of this burgeoning field by a cutting-edge scientific program and roster of distinguished invited speakers and discussion leaders who will address the key issues in the field. The Conference will feature a wide range of topics, such as materials and devices from DNA, reprogramming the genetic code for designmore » of new materials, peptide, protein and carbohydrate based materials, biomimetic systems, complexity in self-assembly, and biomedical applications of bioinspired materials.« less

  20. International Permafrost Field Courses in Siberia: the Synthesis of Research and Education

    NASA Astrophysics Data System (ADS)

    Ablyazina, D.; Boitsov, A.; Grebenets, V.; Kaverin, D.; Klene, A.; Kurchatova, A.; Pfeiffer, E. M.; Zschocke, A.; Shiklomanov, N.; Streletskiy, D.

    2009-04-01

    During summers of 2007 and 2008 a series of International University Courses on Permafrost (IUCP) were conducted in West Siberia, Russia. Courses were organized as part of the International Permafrost Association (IPA) International Polar Year activities. The North of West Siberia region was selected to represent diverse permafrost, climatic and landscape conditions. The courses were jointly organized by the Moscow State University (MSU) and the Tumen' Oil and Gas University (TOGU) with the help from German and U.S. institutions. The program attracted undergraduate and graduate students with diverse interests and backgrounds from Germany, Russia and the U.S. and involved instructors specializing in different aspects of permafrost research. Courses were designed to address three major topics of permafrost-related research: a) permafrost environments characteristic of the discontinuous and continuous zones; b) field instrumentation and techniques; c) permafrost engineering and problems of development in permafrost regions. Methodologically, courses consisted of systematic permafrost investigations at long-term monitoring sites and survey-type expeditions. Systematic, process-based investigations were conducted at a network of sites which constitute the TEPO established by TOGU in collaboration with the gas company NadymGasProm. The observation complex includes an array of 30-m deep boreholes equipped with automatic data collection systems and representing characteristic permafrost landscapes of West Siberia. Boreholes are complemented by sites for snow cover, vegetation, soil, ground ice, and geomorphologic investigations. As part of student research activities, four new Circumpolar Active Layer Monitoring (CALM) sites were established in proximity to boreholes for monitoring spatial distribution and long-term dynamic of the active layer. New sites represent diverse landscapes characteristic of the West Siberian previously underrepresented in the CALM network. Specific emphasis was made on the study of permafrost soils. Throughout the course students were exposed to a wide range of field techniques, including surveying, coring, geothermal monitoring, thaw-depth measurements, landscape characterization, geomorphologic investigations, soil description and classification according to International, Russian, German, and U.S. classification schemes, and hydrologic and botanical field investigations. Significant portion of the course curriculum was devoted to problems of industrial development in permafrost regions. Pipelines, material sites, operating gas wells, processing plants, pump stations, and permafrost engineering testing facilities associated with three major gas fields (Yamburg, Yubileinoe, and Zapolyarnoe) were visited as part of the field excursions. Several meetings with Russian gas industry executives and workers were arranged to openly discuss economic and political issues associated with GasProm activities in West Siberia. The field work was complemented by daily lectures prepared by instructors and students, covering a wide range of topics. Students also participated in active permafrost research through daily data collection and analysis activities. Analysis of the diverse data sets obtained during the course was conducted at Moscow State University, presented in a series of detailed reports. The data collected by students were contributed to the international IPY permafrost monitoring programmes. Several students have presented results of their research at the Ninth International Conference on Permafrost and other national and international scientific meetings. This presentation describes research and educational activities of the IUCP, provides results of student research, and outlines the plan for the future.

  1. 3D Magnetic Reconnection

    NASA Astrophysics Data System (ADS)

    Parnell, Clare E.; Maclean, Rhona C.; Haynes, Andrew L.; Galsgaard, Klaus

    2011-08-01

    Magnetic reconnection is an important process that is prevalent in a wide range of astrophysical bodies. It is the mechanism that permits magnetic fields to relax to a lower energy state through the global restructuring of the magnetic field and is thus associated with a range of dynamic phenomena such as solar flares and CMEs. The characteristics of three-dimensional reconnection are reviewed revealing how much more diverse it is than reconnection in two dimensions. For instance, three-dimensional reconnection can occur both in the vicinity of null points, as well as in the absence of them. It occurs continuously and continually throughout a diffusion volume, as opposed to at a single point, as it does in two dimensions. This means that in three-dimensions field lines do not reconnect in pairs of lines making the visualisation and interpretation of three-dimensional reconnection difficult. By considering particular numerical 3D magnetohydrodynamic models of reconnection, we consider how magnetic reconnection can lead to complex magnetic topologies and current sheet formation. Indeed, it has been found that even simple interactions, such as the emergence of a flux tube, can naturally give rise to `turbulent-like' reconnection regions.

  2. Analytical methods for determination of mycotoxins: An update (2009-2014).

    PubMed

    Turner, Nicholas W; Bramhmbhatt, Heli; Szabo-Vezse, Monika; Poma, Alessandro; Coker, Raymond; Piletsky, Sergey A

    2015-12-11

    Mycotoxins are a problematic and toxic group of small organic molecules that are produced as secondary metabolites by several fungal species that colonise crops. They lead to contamination at both the field and postharvest stages of food production with a considerable range of foodstuffs affected, from coffee and cereals, to dried fruit and spices. With wide ranging structural diversity of mycotoxins, severe toxic effects caused by these molecules and their high chemical stability the requirement for robust and effective detection methods is clear. This paper builds on our previous review and summarises the most recent advances in this field, in the years 2009-2014 inclusive. This review summarises traditional methods such as chromatographic and immunochemical techniques, as well as newer approaches such as biosensors, and optical techniques which are becoming more prevalent. A section on sampling and sample treatment has been prepared to highlight the importance of this step in the analytical methods. We close with a look at emerging technologies that will bring effective and rapid analysis out of the laboratory and into the field. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Bioprospecting and biotechnological applications of fungal laccase.

    PubMed

    Upadhyay, Pooja; Shrivastava, Rahul; Agrawal, Pavan Kumar

    2016-06-01

    Laccase belongs to a small group of enzymes called the blue multicopper oxidases, having the potential ability of oxidation. It belongs to enzymes, which have innate properties of reactive radical production, but its utilization in many fields has been ignored because of its unavailability in the commercial field. There are diverse sources of laccase producing organisms like bacteria, fungi and plants. In fungi, laccase is present in Ascomycetes, Deuteromycetes, Basidiomycetes and is particularly abundant in many white-rot fungi that degrade lignin. Laccases can degrade both phenolic and non-phenolic compounds. They also have the ability to detoxify a range of environmental pollutants. Due to their property to detoxify a range of pollutants, they have been used for several purposes in many industries including paper, pulp, textile and petrochemical industries. Some other application of laccase includes in food processing industry, medical and health care. Recently, laccase has found applications in other fields such as in the design of biosensors and nanotechnology. The present review provides an overview of biological functions of laccase, its mechanism of action, laccase mediator system, and various biotechnological applications of laccase obtained from endophytic fungi.

  4. Dynamics of levitated objects in acoustic vortex fields.

    PubMed

    Hong, Z Y; Yin, J F; Zhai, W; Yan, N; Wang, W L; Zhang, J; Drinkwater, Bruce W

    2017-08-02

    Acoustic levitation in gaseous media provides a tool to process solid and liquid materials without the presence of surfaces such as container walls and hence has been used widely in chemical analysis, high-temperature processing, drop dynamics and bioreactors. To date high-density objects can only be acoustically levitated in simple standing-wave fields. Here we demonstrate the ability of a small number of peripherally placed sources to generate acoustic vortex fields and stably levitate a wide range of liquid and solid objects. The forces exerted by these acoustic vortex fields on a levitated water droplet are observed to cause a controllable deformation of the droplet and/or oscillation along the vortex axis. Orbital angular momentum transfer is also shown to rotate a levitated object rapidly and the rate of rotation can be controlled by the source amplitude. We expect this research can increase the diversity of acoustic levitation and expand the application of acoustic vortices.

  5. Cavity quantum electrodynamics in the nonperturbative regime

    NASA Astrophysics Data System (ADS)

    De Bernardis, Daniele; Jaako, Tuomas; Rabl, Peter

    2018-04-01

    We study a generic cavity-QED system where a set of (artificial) two-level dipoles is coupled to the electric field of a single-mode L C resonator. This setup is used to derive a minimal quantum mechanical model for cavity QED, which accounts for both dipole-field and direct dipole-dipole interactions. The model is applicable for arbitrary coupling strengths and allows us to extend the usual Dicke model into the nonperturbative regime of QED, where the dipole-field interaction can be associated with an effective fine-structure constant of order unity. In this regime, we identify three distinct classes of normal, superradiant, and subradiant vacuum states and discuss their characteristic properties and the transitions between them. Our findings reconcile many of the previous, often contradictory predictions in this field and establish a common theoretical framework to describe ultrastrong-coupling phenomena in a diverse range of cavity-QED platforms.

  6. Agriculture's impact on microbial diversity and associated fluxes of carbon dioxide and methane

    PubMed Central

    Levine, Uri Y; Teal, Tracy K; Robertson, G Philip; Schmidt, Thomas M

    2011-01-01

    Agriculture has marked impacts on the production of carbon dioxide (CO2) and consumption of methane (CH4) by microbial communities in upland soils—Earth's largest biological sink for atmospheric CH4. To determine whether the diversity of microbes that catalyze the flux of these greenhouse gases is related to the magnitude and stability of these ecosystem-level processes, we conducted molecular surveys of CH4-oxidizing bacteria (methanotrophs) and total bacterial diversity across a range of land uses and measured the in situ flux of CH4 and CO2 at a site in the upper United States Midwest. Conversion of native lands to row-crop agriculture led to a sevenfold reduction in CH4 consumption and a proportionate decrease in methanotroph diversity. Sites with the greatest stability in CH4 consumption harbored the most methanotroph diversity. In fields abandoned from agriculture, the rate of CH4 consumption increased with time along with the diversity of methanotrophs. Conversely, estimates of total bacterial diversity in soil were not related to the rate or stability of CO2 emission. These combined results are consistent with the expectation that microbial diversity is a better predictor of the magnitude and stability of processes catalyzed by organisms with highly specialized metabolisms, like CH4 oxidation, as compared with processes driven by widely distributed metabolic processes, like CO2 production in heterotrophs. The data also suggest that managing lands to conserve or restore methanotroph diversity could mitigate the atmospheric concentrations of this potent greenhouse gas. PMID:21490688

  7. A Polarization-Diversity Homodyne Image-Reject Optical Tranceiver Architecture for Improved Range and Signal Detection in Coherent Doppler Lidars

    NASA Astrophysics Data System (ADS)

    Abari, C. F.; Chu, X.; Mann, J.

    2014-12-01

    Doppler light detection and ranging (lidar) has been used for a few decades for the characterization of wind fields and turbulence structures in the atmosphere. More recently, due to the advances in fiber optic communications, all-fiber coherent Doppler lidars (CDL) have been developed and widely used as a primary instrument for probing the atmospheric boundary layer wind fields. Due to a variety of reasons, all-fiber CDLs have gradually replaced their counterparts benefiting from technologies other than fiber optics. Most CDLs suffer from a number of drawbacks inherent to their principle of operation. For instance, one of the main challenges in CDLs is extracting the signal information from noisy observations, which is common to most opto-electronic systems. Moreover, it is sometimes challenging to extract the sign of the measured radial velocity. Conventionally, CDLs have benefitted from an intermediate frequency (IF) heterodyne receiver architecture for the determination of the radial velocity. In such systems, either the transmitted or the local oscillator (LO) signal is shifted in frequency. Such architectures may suffer from increased noise and spurious effects due to the employment of additional active components, e.g., acousto-optic modulator (AOM), limited measurement bandwidth (BW), and a more sophisticated electronic front-end for signal detection. On the other hand, one of the main challenges in long-range (pulsed) CDLs is the limitations imposed on the pulse repetition rate (PRR) as well as the available transmit power. These restrictions are more significant in all-fiber pulsed CDLs in which Erbium doped fiber amplifiers (EDFA) are employed for the amplification of the optical pulses. In this study, we propose an alternative reconfigurable opto-electronic front-end transceiver architecture in all-fiber CDLs where there is no compromise in the detection BW. Additionally, by benefiting from a polarization diversity architecture we show that both the PRR and transmit optical power can be doubled. Other benefits of the proposed system include, but not limited to, capturing additional information about the nature of aerosol particles, improvement of the signal-to-estimation-noise-ratio (SENR), faster scanning of the wind field, and improved measurement range.

  8. Avian diversity and feeding guilds in a secondary forest, an oil palm plantation and a paddy field in riparian areas of the kerian river basin, perak, malaysia.

    PubMed

    Azman, Nur Munira; Latip, Nurul Salmi Abdul; Sah, Shahrul Anuar Mohd; Akil, Mohd Abdul Muin Md; Shafie, Nur Juliani; Khairuddin, Nurul Liyana

    2011-12-01

    The diversity and the feeding guilds of birds in three different habitats (secondary forest, oil palm plantation and paddy field) were investigated in riparian areas of the Kerian River Basin (KRB), Perak, Malaysia. Point-count observation and mist-netting methods were used to determine bird diversity and abundance. A total of 132 species of birds from 46 families were recorded in the 3 habitats. Species diversity, measured by Shannon's diversity index, was 3.561, 3.183 and 1.042 in the secondary forest, the paddy field and the oil palm plantation, respectively. The vegetation diversity and the habitat structure were important determinants of the number of bird species occurring in an area. The relative abundance of the insectivore, insectivore-frugivore and frugivore guilds was greater in the forest than in the monoculture plantation. In contrast, the relative abundance of the carnivore, granivore and omnivore guilds was higher in the plantation. The results of the study show that the conversion of forest to either oil palm plantation or paddy fields produced a decline in bird diversity and changes in the distribution of bird feeding guilds.

  9. Avian Diversity and Feeding Guilds in a Secondary Forest, an Oil Palm Plantation and a Paddy Field in Riparian Areas of the Kerian River Basin, Perak, Malaysia

    PubMed Central

    Azman, Nur Munira; Latip, Nurul Salmi Abdul; Sah, Shahrul Anuar Mohd; Akil, Mohd Abdul Muin Md; Shafie, Nur Juliani; Khairuddin, Nurul Liyana

    2011-01-01

    The diversity and the feeding guilds of birds in three different habitats (secondary forest, oil palm plantation and paddy field) were investigated in riparian areas of the Kerian River Basin (KRB), Perak, Malaysia. Point-count observation and mist-netting methods were used to determine bird diversity and abundance. A total of 132 species of birds from 46 families were recorded in the 3 habitats. Species diversity, measured by Shannon’s diversity index, was 3.561, 3.183 and 1.042 in the secondary forest, the paddy field and the oil palm plantation, respectively. The vegetation diversity and the habitat structure were important determinants of the number of bird species occurring in an area. The relative abundance of the insectivore, insectivore-frugivore and frugivore guilds was greater in the forest than in the monoculture plantation. In contrast, the relative abundance of the carnivore, granivore and omnivore guilds was higher in the plantation. The results of the study show that the conversion of forest to either oil palm plantation or paddy fields produced a decline in bird diversity and changes in the distribution of bird feeding guilds. PMID:24575217

  10. Genotypic Diversity Effects on the Performance of Taraxacum officinale Populations Increase with Time and Environmental Favorability

    PubMed Central

    Drummond, Emily B. M.; Vellend, Mark

    2012-01-01

    Within-population genetic diversity influences many ecological processes, but few studies have examined how environmental conditions may impact these short-term diversity effects. Over four growing seasons, we followed experimental populations of a clonal, ubiquitous weed, Taraxacum officinale, with different numbers of genotypes in relatively favorable fallow field and unfavorable mowed lawn environmental treatments. Population performance (measured as total leaf area, seed production or biomass) clearly and consistently increased with diversity, and this effect became stronger over the course of the experiment. Diversity effects were stronger, and with different underlying mechanisms, in the fallow field versus the mowed lawn. Large genotypes dominated in the fallow field driving overyielding (via positive selection effects), whereas in the mowed lawn, where performance was limited by regular disturbance, there was evidence for complementarity among genotypes (with one compact genotype in particular performing better in mixture than monoculture). Hence, we predict stronger genotypic diversity effects in environments where intense intraspecific competition enhances genotypic differences. Our four-year field experiment plus seedling establishment trials indicate that genotypic diversity effects have far-reaching and context-dependent consequences across generations. PMID:22348004

  11. Response diversity of free-floating plants to nutrient stoichiometry and temperature: growth and resting body formation.

    PubMed

    McCann, Michael J

    2016-01-01

    Free-floating plants, like most groups of aquatic primary producers, can become nuisance vegetation under certain conditions. On the other hand, there is substantial optimism for the applied uses of free-floating plants, such as wastewater treatment, biofuel production, and aquaculture. Therefore, understanding the species-specific responses of floating plants to abiotic conditions will inform both management decisions and the beneficial applications of these plants. I measured the responses of three floating plant species common in the northeast United States (Lemna minor, Spirodela polyrhiza, and Wolffia brasiliensis) to nutrient stoichiometry (nitrogen and phosphorus) and temperature in the laboratory. I also used survey data to determine the pattern of species richness of floating plants in the field and its relationship with the dominance of this group. Floating plant species exhibited unique responses to nutrient stoichiometry and temperature in the laboratory, especially under low temperatures (18 °C) and low nutrient conditions (0.5 mg N L(-1), 0.083 mg P L(-1)). The three species displayed an apparent tradeoff with different strategies of growth or dormancy. In the field, water bodies with three or more species of floating plants were not more frequently dominated by this group. The response diversity observed in the lab may not be associated with the dominance of this group in the field because it is masked by environmental variability, has a weak effect, or is only important during transient circumstances. Future research to develop applied uses of floating plants should examine response diversity across a greater range of species or clones and environmental conditions.

  12. Response diversity of free-floating plants to nutrient stoichiometry and temperature: growth and resting body formation

    PubMed Central

    2016-01-01

    Free-floating plants, like most groups of aquatic primary producers, can become nuisance vegetation under certain conditions. On the other hand, there is substantial optimism for the applied uses of free-floating plants, such as wastewater treatment, biofuel production, and aquaculture. Therefore, understanding the species-specific responses of floating plants to abiotic conditions will inform both management decisions and the beneficial applications of these plants. I measured the responses of three floating plant species common in the northeast United States (Lemna minor, Spirodela polyrhiza, and Wolffia brasiliensis) to nutrient stoichiometry (nitrogen and phosphorus) and temperature in the laboratory. I also used survey data to determine the pattern of species richness of floating plants in the field and its relationship with the dominance of this group. Floating plant species exhibited unique responses to nutrient stoichiometry and temperature in the laboratory, especially under low temperatures (18 °C) and low nutrient conditions (0.5 mg N L−1, 0.083 mg P L−1). The three species displayed an apparent tradeoff with different strategies of growth or dormancy. In the field, water bodies with three or more species of floating plants were not more frequently dominated by this group. The response diversity observed in the lab may not be associated with the dominance of this group in the field because it is masked by environmental variability, has a weak effect, or is only important during transient circumstances. Future research to develop applied uses of floating plants should examine response diversity across a greater range of species or clones and environmental conditions. PMID:26989619

  13. Genetic diversity of human isolates of Salmonella enterica serovar Enteritidis in Malaysia.

    PubMed

    Bakeri, S A; Yasin, R M; Koh, Y T; Puthucheary, S D; Thong, K L

    2003-01-01

    The study was undertaken to determine clonal relationship and genetic diversity of the human strains of Salmonella enterica serovar Enteritidis isolated from 1995 to 2002 from different parts of Malaysia. Antimicrobial susceptibility test, plasmid profiling and pulsed-field gel electrophoresis were applied to analyse 65 human isolates of S. Enteritidis obtained over an eight year period from different parts of Malaysia. Four nonhuman isolates were included for comparison. A total of 14 distinct XbaI-pulsed-field profiles (PFPs) were observed, although a single PFP X1 was predominant and this particular clone was found to be endemic in Malaysia. The incidence of drug resistant S. Enteritidis remained relatively low with only 37% of the strains analysed being resistant to one or more antimicrobial agents. All except one resistant strain carried at least one plasmid ranging in size from 3.7 to 62 MDa giving nine plasmid profiles. The three isolates from raw milk and one from well-water had similar PFPs to that of the human isolates. Salmonella Enteritidis strains were more diverse than was previously thought. Fourteen subtypes were noted although one predominant clone persisted in Malaysia. The combination of pulsed-field gel electrophoresis, plasmid profiling and antibiograms provided additional discrimination to the highly clonal strains of S. Enteritidis. This is the first report to assess the genotypes of the predominant clinical S. Enteritidis in different parts of the country. As S. Enteritidis is highly endemic in Malaysia, the data generated would be useful for tracing the source during outbreaks of gastroenteritis in the study area.

  14. What triggers the rising of an intraspecific biodiversity hotspot? Hints from the agile frog

    PubMed Central

    Canestrelli, Daniele; Bisconti, Roberta; Sacco, Florinda; Nascetti, Giuseppe

    2014-01-01

    Hotspots of genetic diversity are regions of utmost importance for species survival and conservation, and their intimate link with the geographic location of glacial refugia has been well established. Nonetheless, the microevolutionary processes underlying the generation of hotspots in such regions have only recently become a fervent field of research. We investigated the phylogeographic and population genetic structure of the agile frog, Rana dalmatina, within its putative refugium in peninsular Italy. We found this region to harbour far more diversity, phylogeographic structure, and lineages of ancient origin than that by the rest of the species' range in Europe. This pattern appeared to be well explained by climate-driven microevolutionary processes that occurred during both glacial and interglacial epochs. Therefore, the inferred evolutionary history of R. dalmatina in Italy supports a view of glacial refugia as ‘factories' rather than as repositories of genetic diversity, with significant implications for conservation strategies for hotspots. PMID:24853644

  15. 2009 Gordon Research Conference, Applied and Environmental Microbiology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dubilier, Nicole

    The topic of the 2009 Gordon Conference on Applied and Environmental Microbiology is: From Single Cells to the Environment. The Conference will present and discuss cutting-edge research on applied and environmental microbiology with a focus on understanding interactions between microorganisms and the environment at levels ranging from single cells to complex communities. The Conference will feature a wide range of topics such as single cell techniques (including genomics, imaging, and NanoSIMS), microbial diversity at scales ranging from clonal to global, environmental 'meta-omics', biodegradation and bioremediation, metal - microbe interactions, animal microbiomes and symbioses. The Conference will bring together investigators whomore » are at the forefront of their field, and will provide opportunities for junior scientists and graduate students to present their work in poster format and exchange ideas with leaders in the field. Some poster presenters will be selected for short talks. The collegial atmosphere of this Conference, with extensive discussion sessions as well as opportunities for informal gatherings in the afternoons and evenings, provides an ideal setting for scientists from different disciplines to exchange ideas, brainstorm and discuss cross-disciplinary collaborations.« less

  16. Demonstration of a mid-infrared NO molecular Faraday optical filter.

    PubMed

    Wu, Kuijun; Feng, Yutao; Li, Juan; Yu, Guangbao; Liu, Linmei; Xiong, Yuanhui; Li, Faquan

    2017-12-11

    A molecular Faraday optical filter (MFOF) working in the mid-infrared region is realized for the first time. NO molecule was used as the working material of the MFOF for potential applications in atmospheric remote sensing and combustion diagnosis. We develop a complete theory to describe the performance of MFOF by taking both Zeeman absorption and Faraday rotation into account. We also record the Faraday rotation transmission (FRT) signal using a quantum cascade laser over the range of 1,820 cm -1 to 1,922 cm -1 and calibrate it by using a 101.6 mm long solid germanium etalon with a free spectral range of 0.012 cm -1 . Good agreement between the simulation results and experimental data is achieved. The NO-MFOF's transmission characteristics as a function of magnetic field and pressure are studied in detail. Both Comb-like FRT spectrum and single branch transmission spectrum are obtained by changing the magnetic field. The diversity of FRT spectrum expands the range of potential applications in infrared optical remote sensing. This filtering method can also be extended to the lines of other paramagnetic molecules.

  17. An Overview of Internet biosurveillance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hartley, David M.; Nelson, Noele P.; Arthur, Ray

    Internet biosurveillance utilizes unstructured data from diverse Web-based sources to provide early warning and situational awareness of public health threats. The scope of source coverage ranges from local based media in the vernacular to international media in widely read languages. Internet biosurveillance is a timely modality available to government and public health officials, health care workers, and the public and private sector, serving as a real-time complementary approach to traditional indicator-based public health disease surveillance methods. Internet biosurveillance also supports the broader activity of epidemic intelligence. This review covers the current state of the field of Internet biosurveillance and providesmore » a perspective on the future of the field.« less

  18. Multiscale Characterization of the Probability Density Functions of Velocity and Temperature Increment Fields

    NASA Astrophysics Data System (ADS)

    DeMarco, Adam Ward

    The turbulent motions with the atmospheric boundary layer exist over a wide range of spatial and temporal scales and are very difficult to characterize. Thus, to explore the behavior of such complex flow enviroments, it is customary to examine their properties from a statistical perspective. Utilizing the probability density functions of velocity and temperature increments, deltau and deltaT, respectively, this work investigates their multiscale behavior to uncover the unique traits that have yet to be thoroughly studied. Utilizing diverse datasets, including idealized, wind tunnel experiments, atmospheric turbulence field measurements, multi-year ABL tower observations, and mesoscale models simulations, this study reveals remarkable similiarities (and some differences) between the small and larger scale components of the probability density functions increments fields. This comprehensive analysis also utilizes a set of statistical distributions to showcase their ability to capture features of the velocity and temperature increments' probability density functions (pdfs) across multiscale atmospheric motions. An approach is proposed for estimating their pdfs utilizing the maximum likelihood estimation (MLE) technique, which has never been conducted utilizing atmospheric data. Using this technique, we reveal the ability to estimate higher-order moments accurately with a limited sample size, which has been a persistent concern for atmospheric turbulence research. With the use robust Goodness of Fit (GoF) metrics, we quantitatively reveal the accuracy of the distributions to the diverse dataset. Through this analysis, it is shown that the normal inverse Gaussian (NIG) distribution is a prime candidate to be used as an estimate of the increment pdfs fields. Therefore, using the NIG model and its parameters, we display the variations in the increments over a range of scales revealing some unique scale-dependent qualities under various stability and ow conditions. This novel approach can provide a method of characterizing increment fields with the sole use of only four pdf parameters. Also, we investigate the capability of the current state-of-the-art mesoscale atmospheric models to predict the features and highlight the potential for use for future model development. With the knowledge gained in this study, a number of applications can benefit by using our methodology, including the wind energy and optical wave propagation fields.

  19. Modeling a synthetic multicellular clock: repressilators coupled by quorum sensing.

    PubMed

    Garcia-Ojalvo, Jordi; Elowitz, Michael B; Strogatz, Steven H

    2004-07-27

    Diverse biochemical rhythms are generated by thousands of cellular oscillators that somehow manage to operate synchronously. In fields ranging from circadian biology to endocrinology, it remains an exciting challenge to understand how collective rhythms emerge in multicellular structures. Using mathematical and computational modeling, we study the effect of coupling through intercell signaling in a population of Escherichia coli cells expressing a synthetic biological clock. Our results predict that a diverse and noisy community of such genetic oscillators interacting through a quorum-sensing mechanism should self-synchronize in a robust way, leading to a substantially improved global rhythmicity in the system. As such, the particular system of coupled genetic oscillators considered here might be a good candidate to provide the first quantitative example of a synchronization transition in a population of biological oscillators.

  20. Modeling a synthetic multicellular clock: Repressilators coupled by quorum sensing

    NASA Astrophysics Data System (ADS)

    Garcia-Ojalvo, Jordi; Elowitz, Michael B.; Strogatz, Steven H.

    2004-07-01

    Diverse biochemical rhythms are generated by thousands of cellular oscillators that somehow manage to operate synchronously. In fields ranging from circadian biology to endocrinology, it remains an exciting challenge to understand how collective rhythms emerge in multicellular structures. Using mathematical and computational modeling, we study the effect of coupling through intercell signaling in a population of Escherichia coli cells expressing a synthetic biological clock. Our results predict that a diverse and noisy community of such genetic oscillators interacting through a quorum-sensing mechanism should self-synchronize in a robust way, leading to a substantially improved global rhythmicity in the system. As such, the particular system of coupled genetic oscillators considered here might be a good candidate to provide the first quantitative example of a synchronization transition in a population of biological oscillators.

  1. Toward a Neural Basis for Social Behavior

    PubMed Central

    Stanley, Damian A.; Adolphs, Ralph

    2014-01-01

    Nearly 25 years ago, the shared interests of psychologists and biologists in understanding the neural basis of social behavior led to the inception of social neuroscience. In the past decade, this field has exploded, in large part due to the infusion of studies that use fMRI. At the same time, tensions have arisen about how to prioritize a diverse range of questions and about the authority of neurobiological data in answering them. The field is now poised to tackle some of the most interesting and important questions about human and animal behavior but at the same time faces uncertainty about how to achieve focus in its research and cohesion among the scientists who tackle it. The next 25 years offer the opportunity to alleviate some of these growing pains, as well as the challenge of answering large questions that encompass the nature and bounds of diverse social interactions (in humans, including interactions through the internet); how to characterize, and treat, social dysfunction in psychiatric illness; and how to compare social cognition in humans with that in other animals. PMID:24183030

  2. Toward a neural basis for social behavior.

    PubMed

    Stanley, Damian A; Adolphs, Ralph

    2013-10-30

    Nearly 25 years ago, the shared interests of psychologists and biologists in understanding the neural basis of social behavior led to the inception of social neuroscience. In the past decade, this field has exploded, in large part due to the infusion of studies that use fMRI. At the same time, tensions have arisen about how to prioritize a diverse range of questions and about the authority of neurobiological data in answering them. The field is now poised to tackle some of the most interesting and important questions about human and animal behavior but at the same time faces uncertainty about how to achieve focus in its research and cohesion among the scientists who tackle it. The next 25 years offer the opportunity to alleviate some of these growing pains, as well as the challenge of answering large questions that encompass the nature and bounds of diverse social interactions (in humans, including interactions through the internet); how to characterize, and treat, social dysfunction in psychiatric illness; and how to compare social cognition in humans with that in other animals. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Low archaeal diversity linked to subseafloor geochemical processes at the Lost City Hydrothermal Field, Mid-Atlantic Ridge.

    PubMed

    Schrenk, Matthew O; Kelley, Deborah S; Bolton, Sheryl A; Baross, John A

    2004-10-01

    The recently discovered Lost City Hydrothermal Field (LCHF) represents a new type of submarine hydrothermal system driven primarily by exothermic serpentinization reactions in ultramafic oceanic crust. Highly reducing, alkaline hydrothermal environments at the LCHF produce considerable quantities of hydrogen, methane and organic molecules through chemo- and biosynthetic reactions. Here, we report the first analyses of microbial communities inhabiting carbonate chimneys awash in warm, high pH fluids at the LCHF and the predominance of a single group of methane-metabolizing Archaea. The predominant phylotype, related to the Methanosarcinales, formed tens of micrometre-thick biofilms in regions adjacent to hydrothermal flow. Exterior portions of active structures harboured a diverse microbial community composed primarily of filamentous Eubacteria that resembled sulphide-oxidizing species. Inactive samples, away from regions of hydrothermal flow, contained phylotypes related to pelagic microorganisms. The abundance of organisms linked to the volatile chemistry at the LCHF hints that similar metabolic processes may operate in the subseafloor. These results expand the range of known geological settings that support biological activity to include submarine hydrothermal systems that are not dependent upon magmatic heat sources.

  4. Recent advances in designed coiled coils and helical bundles with inorganic prosthetic groups-from structural to functional applications.

    PubMed

    Peacock, Anna Fa

    2016-04-01

    Recent contributions to the de novo design of metalloproteins based on coiled coils and helical bundles are described herein, with examples covering mononuclear, multinuclear, and metallo-porphyrin sites, as well as membrane soluble designs. Important progress is being made in the field with a diverse range of functionalities, sometimes beyond those found in biology, being successfully engineered into these simplified scaffolds and represents an exciting prospect for the future. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Development of Cellulosic Biofuels (LBNL Summer Lecture Series)

    ScienceCinema

    Somerville, Chris [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Physical Biosciences Division; Stanford Univ., CA (United States). Dept. of Biological Sciences

    2018-05-18

    Summer Lecture Series 2007: Chris Somerville, Director of the Energy Biosciences Institute and an award-winning plant biochemist with Berkeley Lab's Physical Biosciences Division, is a leading authority on the structure and function of plant cell walls. He discusses an overview of some of the technical challenges associated with the production of cellulosic biofuels, which will require an improved understanding of a diverse range of topics in fields such as agronomy, chemical engineering, microbiology, structural biology, genomics, environmental sciences, and socioeconomics.

  6. Rich Support for Heterogeneous Polar Data in RAMADDA

    NASA Astrophysics Data System (ADS)

    McWhirter, J.; Crosby, C. J.; Griffith, P. C.; Khalsa, S.; Lazzara, M. A.; Weber, W. J.

    2013-12-01

    Difficult to navigate environments, tenuous logistics, strange forms, deeply rooted cultures - these are all experiences shared by Polar scientist in the field as well as the developers of the underlying data management systems back in the office. Among the key data management challenges that Polar investigations present are the heterogeneity and complexity of data that are generated. Polar regions are intensely studied across many science domains through a variety of techniques - satellite and aircraft remote sensing, in-situ observation networks, modeling, sociological investigations, and extensive PI-driven field project data collection. While many data management efforts focus on large homogeneous collections of data targeting specific science domains (e.g., satellite, GPS, modeling), multi-disciplinary efforts that focus on Polar data need to be able to address a wide range of data formats, science domains and user communities. There is growing use of the RAMADDA (Repository for Archiving, Managing and Accessing Diverse Data) system to manage and provide services for Polar data. RAMADDA is a freely available extensible data repository framework that supports a wide range of data types and services to allow the creation, management, discovery and use of data and metadata. The broad range of capabilities provided by RAMADDA and its extensibility makes it well-suited as an archive solution for Polar data. RAMADDA can run in a number of diverse contexts - as a centralized archive, at local institutions, and can even run on an investigator's laptop in the field, providing in-situ metadata and data management services. We are actively developing archives and support for a number of Polar initiatives: - NASA-Arctic Boreal Vulnerability Experiment (ABoVE): ABoVE is a long-term multi-instrument field campaign that will make use of a wide range of data. We have developed an extensive ontology of program, project and site metadata in RAMADDA, in support of the ABoVE Science Definition Team and Project Office. See: http://above.nasa.gov - UNAVCO Terrestrial Laser Scanning (TLS): UNAVCO's Polar program provides support for terrestrial laser scanning field projects. We are using RAMADDA to archive these field projects, with over 40 projects ingested to date. - NASA-IceBridge: As part of the NASA LiDAR Access System (NLAS) project, RAMADDA supports numerous airborne and satellite LiDAR data sets - GLAS, LVIS, ATM, Paris, McORDS, etc. - Antarctic Meteorological Research Center (AMRC): Satellite and surface observation network - Support for numerous other data from AON-ACADIS, Greenland GC-Net, NOAA-GMD, AmeriFlux, etc. In this talk we will discuss some of the challenges that Polar data brings to geoinformatics and describe the approaches we have taken to address these challenges in RAMADDA.

  7. High taxonomic diversity of cultivation-recalcitrant endophytic bacteria in grapevine field shoots, their in vitro introduction, and unsuspected persistence.

    PubMed

    Thomas, Pious; Sekhar, Aparna C; Shaik, Sadiq Pasha

    2017-11-01

    Molecular and microscopic analyses reveal enormous non-cultivable endophytic bacteria in grapevine field shoots with functional significance. Diverse bacteria enter tissue cultures through surface-sterilized tissues and survive surreptitiously with varying taxonomic realignments. The study was envisaged to assess the extent of endophytic bacterial association with field shoot tissues of grapevine and the likelihood of introduction of such internally colonizing bacteria in vitro adopting molecular techniques targeting the non-cultivable bacterial community. PowerFood ® -kit derived DNA from surface-sterilized field shoot tips of grapevine Flame Seedless was employed in a preliminary bacterial class-specific PCR screening proving positive for major prokaryotic taxa including Archaea. Taxonomic and functional diversity were analyzed through whole metagenome profiling (WMG) which revealed predominantly phylum Actinobacteria, Proteobacteria, and minor shares of Firmicutes, Bacteroidetes, and Deinococcus-Thermus with varying functional roles ascribable to the whole bacterial community. Field shoot tip tissues and callus derived from stem segments were further employed in 16S rRNA V3-V4 amplicon taxonomic profiling. This revealed elevated taxonomic diversity in field shoots over WMG, predominantly Proteobacteria succeeded by Actinobacteria, Firmicutes, Bacteroidetes, and 15 other phyla including several candidate phyla (135 families, 179 genera). Callus stocks also displayed broad bacterial diversity (16 phyla; 96 families; 141 genera) bearing resemblance to field tissues with Proteobacterial dominance but a reduction in its share, enrichment of Actinobacteria and Firmicutes, disappearance of some field-associated phyla and detection of a few additional taxonomic groups over field community. Similar results were documented during 16S V3-V4 amplicon taxonomic profiling on Thompson Seedless field shoot tip and callus tissues. Video microscopy on tissue homogenates corroborated enormous endophytic bacteria. This study elucidates a vast diversity of cultivation-recalcitrant endophytic bacteria prevailing in grapevine field shoots, their in vitro introduction, and unsuspecting sustenance with possible silent participation in tissue culture processes.

  8. Enhancing the diversity of breeding invertebrates within field margins of intensively managed grassland: Effects of alternative management practices.

    PubMed

    Fritch, Rochelle A; Sheridan, Helen; Finn, John A; McCormack, Stephen; Ó hUallacháin, Daire

    2017-11-01

    Severe declines in biodiversity have been well documented for many taxonomic groups due to intensification of agricultural practices. Establishment and appropriate management of arable field margins can improve the diversity and abundance of invertebrate groups; however, there is much less research on field margins within grassland systems. Three grassland field margin treatments (fencing off the existing vegetation "fenced"; fencing with rotavation and natural regeneration "rotavated" and; fencing with rotavation and seeding "seeded") were compared to a grazed control in the adjacent intensively managed pasture. Invertebrates were sampled using emergence traps to investigate species breeding and overwintering within the margins. Using a manipulation experiment, we tested whether the removal of grazing pressure and nutrient inputs would increase the abundance and richness of breeding invertebrates within grassland field margins. We also tested whether field margin establishment treatments, with their different vegetation communities, would change the abundance and richness of breeding invertebrates in the field margins. Exclusion of grazing and nutrient inputs led to increased abundance and richness in nearly all invertebrate groups that we sampled. However, there were more complex effects of field margin establishment treatment on the abundance and richness of invertebrate taxa. Each of the three establishment treatments supported a distinct invertebrate community. The removal of grazing from grassland field margins provided a greater range of overwintering/breeding habitat for invertebrates. We demonstrate the capacity of field margin establishment to increase the abundance and richness in nearly all invertebrate groups in study plots that were located on previously more depauperate areas of intensively managed grassland. These results from grassland field margins provide evidence to support practical actions that can inform Greening (Pillar 1) and agri-environment measures (Pillar 2) of the Common Agricultural Policy (CAP). Before implementing specific management regimes, the conservation aims of agri-environment measures should be clarified by defining the target species or taxonomic groups.

  9. Expansion Under Climate Change: The Genetic Consequences.

    PubMed

    Garnier, Jimmy; Lewis, Mark A

    2016-11-01

    Range expansion and range shifts are crucial population responses to climate change. Genetic consequences are not well understood but are clearly coupled to ecological dynamics that, in turn, are driven by shifting climate conditions. We model a population with a deterministic reaction-diffusion model coupled to a heterogeneous environment that develops in time due to climate change. We decompose the resulting travelling wave solution into neutral genetic components to analyse the spatio-temporal dynamics of its genetic structure. Our analysis shows that range expansions and range shifts under slow climate change preserve genetic diversity. This is because slow climate change creates range boundaries that promote spatial mixing of genetic components. Mathematically, the mixing leads to so-called pushed travelling wave solutions. This mixing phenomenon is not seen in spatially homogeneous environments, where range expansion reduces genetic diversity through gene surfing arising from pulled travelling wave solutions. However, the preservation of diversity is diminished when climate change occurs too quickly. Using diversity indices, we show that fast expansions and range shifts erode genetic diversity more than slow range expansions and range shifts. Our study provides analytical insight into the dynamics of travelling wave solutions in heterogeneous environments.

  10. Eleven years of crop diversification alters decomposition dynamics of litter mixtures incubated with soil

    DOE PAGES

    McDaniel, M. D.; Grandy, A. S.; Tiemann, L. K.; ...

    2016-08-11

    Agricultural crop rotations have been shown to increase soil carbon (C), nitrogen (N), and microbial biomass. The mechanisms behind these increases remain unclear, but may be linked to the diversity of crop residue inputs to soil organic matter (SOM). Here, we used a residue mixture incubation to examine how variation in long-term diversity of plant communities in agroecosystems influences decomposition of residue mixtures, thus providing a comparison of the effects of plant diversification on decomposition in the long term (via crop rotation) and short term (via residue mixtures). Three crop residue mixtures, ranging in diversity from two to four species,more » were incubated for 360 d with soils from five crop rotations, ranging from monoculture corn (mC) to a complex five-crop rotation. In response, we measured fundamental soil pools and processes underlying C and N cycling. These included soil respiration, inorganic N, microbial biomass, and extracellular enzymes. We hypothesized that soils with more diverse cropping histories would show greater synergistic mixture effects than mC. For most variables (except extracellular enzymes), crop rotation history, or the long-term history of plant diversity in the field, had a stronger effect on soil processes than mixture composition. In contrast to our hypothesis, the mC soil had nearly three and seven times greater synergistic mixture effects for respiration and microbial biomass N, respectively, compared with soils from crop rotations. This was due to the low response of the mC soils to poor quality residues (corn and wheat), likely resulting from a lack of available C and nutrients to cometabolize these residues. These results indicate that diversifying crop rotations in agricultural systems alter the decomposition dynamics of new residue inputs, which may be linked to the benefits of increasing crop rotation diversity on soil nutrient cycling, SOM dynamics, and yields.« less

  11. Crop diversity loss as primary cause of grey partridge and common pheasant decline in Lower Saxony, Germany.

    PubMed

    Ronnenberg, Katrin; Strauß, Egbert; Siebert, Ursula

    2016-09-09

    The grey partridge (Perdix perdix) and the common pheasant (Phasianus colchicus) are galliform birds typical of arable lands in Central Europe and exhibit a partly dramatic negative population trend. In order to understand general habitat preferences we modelled grey partridge and common pheasant densities over the entire range of Lower Saxony. Spatially explicit developments in bird densities were modelled using spatially explicit trends of crop cultivation. Pheasant and grey partridge densities counted annually by over 8000 hunting district holders over 10 years in a range of 3.7 Mio ha constitute a unique dataset (wildlife survey of Lower Saxony). Data on main landscape groups, functional groups of agricultural crops (consisting of 9.5 million fields compiled by the Integrated Administration and Control System) and landscape features were aggregated to 420 municipalities. To model linear 8 or 10 year population trends (for common pheasant and grey partridge respectively) we use rho correlation coefficients of densities, but also rho coefficients of agricultural crops. All models confirm a dramatic decline in population densities. The habitat model for the grey partridge shows avoidance of municipalities with a high proportion of woodland and water areas, but a preference for areas with a high proportion of winter grains and high crop diversity. The trend model confirms these findings with a linear positive effect of diversity on grey partridge population development. Similarly, the pheasant avoids wooded areas but showed some preference for municipalities with open water. The effect of maize was found to be positive at medium densities, but negative at very high proportions. Winter grains, landscape features and high crop diversity are favorable. The positive effect of winter grains and higher crop diversity is also supported by the trend model. The results show the strong importance of diverse crop cultivation. Most incentives favor the cultivation of specific crops, which results in large areas of monocultures. The results confirm the importance of sustainable agricultural policies.

  12. Geogenic Factors as Drivers of Microbial Community Diversity in Soils Overlying Polymetallic Deposits.

    PubMed

    Reith, Frank; Zammit, Carla M; Pohrib, Rebecca; Gregg, Adrienne L; Wakelin, Steven A

    2015-11-01

    This study shows that the geogenic factors landform, lithology, and underlying mineral deposits (expressed by elevated metal concentrations in overlying soils) are key drivers of microbial community diversity in naturally metal-rich Australian soils with different land uses, i.e., agriculture versus natural bushland. One hundred sixty-eight soil samples were obtained from two metal-rich provinces in Australia, i.e., the Fifield Au-Pt field (New South Wales) and the Hillside Cu-Au-U rare-earth-element (REE) deposit (South Australia). Soils were analyzed using three-domain multiplex terminal-restriction-fragment-length-polymorphism (M-TRFLP) and PhyloChip microarrays. Geogenic factors were determined using field-mapping techniques and analyses of >50 geochemical parameters. At Fifield, microbial communities differed significantly with geogenic factors and equally with land use (P < 0.05). At Hillside, communities in surface soils (0.03- to 0.2-m depth) differed significantly with landform and land use (P < 0.05). Communities in deeper soils (>0.2 m) differed significantly with lithology and mineral deposit (P < 0.05). Across both sites, elevated metal contents in soils overlying mineral deposits were selective for a range of bacterial taxa, most importantly Acidobacteria, Bacilli, Betaproteobacteria, and Epsilonproteobacteria. In conclusion, long-term geogenic factors can be just as important as land use in determining soil microbial community diversity. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  13. Geogenic Factors as Drivers of Microbial Community Diversity in Soils Overlying Polymetallic Deposits

    PubMed Central

    Zammit, Carla M.; Pohrib, Rebecca; Gregg, Adrienne L.; Wakelin, Steven A.

    2015-01-01

    This study shows that the geogenic factors landform, lithology, and underlying mineral deposits (expressed by elevated metal concentrations in overlying soils) are key drivers of microbial community diversity in naturally metal-rich Australian soils with different land uses, i.e., agriculture versus natural bushland. One hundred sixty-eight soil samples were obtained from two metal-rich provinces in Australia, i.e., the Fifield Au-Pt field (New South Wales) and the Hillside Cu-Au-U rare-earth-element (REE) deposit (South Australia). Soils were analyzed using three-domain multiplex terminal-restriction-fragment-length-polymorphism (M-TRFLP) and PhyloChip microarrays. Geogenic factors were determined using field-mapping techniques and analyses of >50 geochemical parameters. At Fifield, microbial communities differed significantly with geogenic factors and equally with land use (P < 0.05). At Hillside, communities in surface soils (0.03- to 0.2-m depth) differed significantly with landform and land use (P < 0.05). Communities in deeper soils (>0.2 m) differed significantly with lithology and mineral deposit (P < 0.05). Across both sites, elevated metal contents in soils overlying mineral deposits were selective for a range of bacterial taxa, most importantly Acidobacteria, Bacilli, Betaproteobacteria, and Epsilonproteobacteria. In conclusion, long-term geogenic factors can be just as important as land use in determining soil microbial community diversity. PMID:26341204

  14. Diversity of Edible and Medicinal Mushrooms Used in the Noun Division of the West Region of Cameroon.

    PubMed

    Njouonkou, André Ledoux; De Crop, Eske; Mbenmoun, Abdoulayi Mbouombouo; Kinge, Tonjock Rosemary; Biyé, Elvire Hortense; Verbeken, Annemieke

    2016-01-01

    This article presents discussions of mushrooms as a source of food, income, as well as medicine among the Bamoun people of the highlands of West Cameroon, where the vegetation is mainly savannah mixed with forest galleries. Like most tribes in tropical Africa, the Bamoun people use a wide range of natural products as mushrooms. This study attempts to identify the various mushrooms exploited by the Bamoun. Ethnomycological surveys and field trips were conducted over 4 years in several villages in the Noun Division. Samples of wild mushrooms were collected from both the savannah and the forest galleries. These were described, preserved, and identified. The study shows that the Bamoun people use at least 40 species of mushrooms for either food or medicine. These species belong to 8 genera: Auricularia, Cantharellus, Ganoderma, Pleurotus, Lactarius, Lactifluus, Russula, and Termitomyces. Species of genera Lactarius, Lactifluus, Russula, and Termitomyces are most often used for food, whereas Ganoderma spp. and Pleurotus tuber-regium are mainly exploited for medicinal purposes. This survey provides an overview of the diversity of mushrooms and their importance to the local people of this area. Since some of the species mentioned by the local population were not fruiting at the time of our field trips, additional investigations are needed to further clarify the diversity and the usage of mushrooms in this region.

  15. Foundational Field Experiences: A Window into Preservice Teachers' Cultural Consciousness and Self-Efficacy for Teaching Diverse Learners

    ERIC Educational Resources Information Center

    Lastrapes, Wanda; Negishi, Meiko

    2012-01-01

    This study examined preservice teachers' cultural consciousness and self-efficacy while tutoring diverse students during an initial urban field experience. The 46 participants, enrolled in an introduction to diversity course, completed an 18-hour tutoring requirement in elementary and secondary schools. Paired-sample t-tests yielded statistically…

  16. Genetic diversity demonstrated by pulsed field gel electrophoresis of Salmonella enterica isolates obtained from diverse sources in Mexico

    USDA-ARS?s Scientific Manuscript database

    This study was conducted to determine the genetic diversity of Salmonella isolates recovered from a variety of sources using pulsed-field gel electrophoresis (PFGE) to assess their possible relatedness. Salmonella was isolated from ca. 52% of samples from a pepper var. Bell production system. A to...

  17. NASA Tech Briefs, April 2007

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Topics include: Wearable Environmental and Physiological Sensing Unit; Broadband Phase Retrieval for Image-Based Wavefront Sensing; Filter Function for Wavefront Sensing Over a Field of View; Iterative-Transform Phase Retrieval Using Adaptive Diversity; Wavefront Sensing With Switched Lenses for Defocus Diversity; Smooth Phase Interpolated Keying; Maintaining Stability During a Conducted-Ripple EMC Test; Photodiode Preamplifier for Laser Ranging With Weak Signals; Advanced High-Definition Video Cameras; Circuit for Full Charging of Series Lithium-Ion Cells; Analog Nonvolatile Computer Memory Circuits; JavaGenes Molecular Evolution; World Wind 3D Earth Viewing; Lithium Dinitramide as an Additive in Lithium Power Cells; Accounting for Uncertainties in Strengths of SiC MEMS Parts; Ion-Conducting Organic/Inorganic Polymers; MoO3 Cathodes for High-Temperature Lithium Thin-Film Cells; Counterrotating-Shoulder Mechanism for Friction Stir Welding; Strain Gauges Indicate Differential-CTE-Induced Failures; Antibodies Against Three Forms of Urokinase; Understanding and Counteracting Fatigue in Flight Crews; Active Correction of Aberrations of Low-Quality Telescope Optics; Dual-Beam Atom Laser Driven by Spinor Dynamics; Rugged, Tunable Extended-Cavity Diode Laser; Balloon for Long-Duration, High-Altitude Flight at Venus; and Wide-Temperature-Range Integrated Operational Amplifier.

  18. Environmental contaminants of health-care origin: Exposure and potential effects in wildlife

    USGS Publications Warehouse

    Bean, Thomas; Rattner, Barnett A.

    2018-01-01

    A diverse range of fauna could be exposed to active pharmaceutical ingredients (APIs) via diet, dermal absorption or bioconcentration. Low level exposures of free-ranging wildlife to APIs has only been demonstrated for a few pathways (e.g., ingestion of fish in estuaries by piscivorous birds), and many remain hypothetical (e.g., ingestion of invertebrates in sludge amended fields by terrestrial vertebrates). Our understanding of API dose-response relationships in wildlife have only been assessed for endocrine disrupting compounds and a few veterinary therapeutics. Drug specific responses at various levels of biological organization are poorly characterized for nearly all wildlife species, and thus our understanding of risk is limited. There is interest in using a read-across approach to fill knowledge gaps for risk. This approach, using data collected in laboratory mammals and humans, would enable predictions for likelihood of adverse effects in wildlife. Given the great diversities in physiologies among species, a combination of in vivo, in vitro and in silico approaches will be required to fill the knowledge gaps for exposure, hazard and risk.

  19. Real-Time DNA Sequencing in the Antarctic Dry Valleys Using the Oxford Nanopore Sequencer

    PubMed Central

    Johnson, Sarah S.; Zaikova, Elena; Goerlitz, David S.; Bai, Yu; Tighe, Scott W.

    2017-01-01

    The ability to sequence DNA outside of the laboratory setting has enabled novel research questions to be addressed in the field in diverse areas, ranging from environmental microbiology to viral epidemics. Here, we demonstrate the application of offline DNA sequencing of environmental samples using a hand-held nanopore sequencer in a remote field location: the McMurdo Dry Valleys, Antarctica. Sequencing was performed using a MK1B MinION sequencer from Oxford Nanopore Technologies (ONT; Oxford, United Kingdom) that was equipped with software to operate without internet connectivity. One-direction (1D) genomic libraries were prepared using portable field techniques on DNA isolated from desiccated microbial mats. By adequately insulating the sequencer and laptop, it was possible to run the sequencing protocol for up to 2½ h under arduous conditions. PMID:28337073

  20. Spatial Biodiversity Patterns of Madagascar's Amphibians and Reptiles

    PubMed Central

    Brown, Jason L.; Sillero, Neftali; Glaw, Frank; Bora, Parfait; Vieites, David R.; Vences, Miguel

    2016-01-01

    Madagascar has become a model region for testing hypotheses of species diversification and biogeography, and many studies have focused on its diverse and highly endemic herpetofauna. Here we combine species distribution models of a near-complete set of species of reptiles and amphibians known from the island with body size data and a tabulation of herpetofaunal communities from field surveys, compiled up to 2008. Though taxonomic revisions and novel distributional records arose since compilation, we are confident that the data are appropriate for inferring and comparing biogeographic patterns among these groups of organisms. We observed species richness of both amphibians and reptiles was highest in the humid rainforest biome of eastern Madagascar, but reptiles also show areas of high richness in the dry and subarid western biomes. In several amphibian subclades, especially within the Mantellidae, species richness peaks in the central eastern geographic regions while in reptiles different subclades differ distinctly in their richness centers. A high proportion of clades and subclades of both amphibians and reptiles have a peak of local endemism in the topographically and bioclimatically diverse northern geographic regions. This northern area is roughly delimited by a diagonal spanning from 15.5°S on the east coast to ca. 15.0°S on the west coast. Amphibian diversity is highest at altitudes between 800–1200 m above sea-level whereas reptiles have their highest richness at low elevations, probably reflecting the comparatively large number of species specialized to the extended low-elevation areas in the dry and subarid biomes. We found that the range sizes of both amphibians and reptiles strongly correlated with body size, and differences between the two groups are explained by the larger body sizes of reptiles. However, snakes have larger range sizes than lizards which cannot be readily explained by their larger body sizes alone. Range filling, i.e., the amount of suitable habitat occupied by a species, is less expressed in amphibians than in reptiles, possibly reflecting their lower dispersal capacity. Taxonomic composition of communities assessed by field surveys is largely explained by bioclimatic regions, with communities from the dry and especially subarid biomes distinctly differing from humid and subhumid biomes. PMID:26735688

  1. Spatial Biodiversity Patterns of Madagascar's Amphibians and Reptiles.

    PubMed

    Brown, Jason L; Sillero, Neftali; Glaw, Frank; Bora, Parfait; Vieites, David R; Vences, Miguel

    2016-01-01

    Madagascar has become a model region for testing hypotheses of species diversification and biogeography, and many studies have focused on its diverse and highly endemic herpetofauna. Here we combine species distribution models of a near-complete set of species of reptiles and amphibians known from the island with body size data and a tabulation of herpetofaunal communities from field surveys, compiled up to 2008. Though taxonomic revisions and novel distributional records arose since compilation, we are confident that the data are appropriate for inferring and comparing biogeographic patterns among these groups of organisms. We observed species richness of both amphibians and reptiles was highest in the humid rainforest biome of eastern Madagascar, but reptiles also show areas of high richness in the dry and subarid western biomes. In several amphibian subclades, especially within the Mantellidae, species richness peaks in the central eastern geographic regions while in reptiles different subclades differ distinctly in their richness centers. A high proportion of clades and subclades of both amphibians and reptiles have a peak of local endemism in the topographically and bioclimatically diverse northern geographic regions. This northern area is roughly delimited by a diagonal spanning from 15.5°S on the east coast to ca. 15.0°S on the west coast. Amphibian diversity is highest at altitudes between 800-1200 m above sea-level whereas reptiles have their highest richness at low elevations, probably reflecting the comparatively large number of species specialized to the extended low-elevation areas in the dry and subarid biomes. We found that the range sizes of both amphibians and reptiles strongly correlated with body size, and differences between the two groups are explained by the larger body sizes of reptiles. However, snakes have larger range sizes than lizards which cannot be readily explained by their larger body sizes alone. Range filling, i.e., the amount of suitable habitat occupied by a species, is less expressed in amphibians than in reptiles, possibly reflecting their lower dispersal capacity. Taxonomic composition of communities assessed by field surveys is largely explained by bioclimatic regions, with communities from the dry and especially subarid biomes distinctly differing from humid and subhumid biomes.

  2. The role of nitrogen fixation in neotropical dry forests: insights from ecosystem modeling and field data

    NASA Astrophysics Data System (ADS)

    Trierweiler, A.; Xu, X.; Gei, M. G.; Powers, J. S.; Medvigy, D.

    2016-12-01

    Tropical dry forests (TDFs) have immense functional diversity and face multiple resource constraints (both water and nutrients). Legumes are abundant and exhibit a wide diversity of N2-fixing strategies in TDFs. The abundance and diversity of legumes and their interaction with N2-fixing bacteria may strongly control the coupled carbon-nitrogen cycle in the biome and influence whether TDFs will be particularly vulnerable or uniquely adapted to projected global change. However, the importance of N2-fixation in TDFs and the carbon cost of acquiring N through symbiotic relationships are not fully understood. Here, we use models along with field measurements to examine the role of legumes, nitrogen fixation, and plant-symbiont nutrient exchanges in TDFs. We use a new version of the Ecosystem Demography (ED2) model that has been recently parameterized for TDFs. The new version incorporates plant-mycorrhizae interactions and multiple resource constraints (carbon, nitrogen, phosphorus, and water). We represent legumes and other functional groups found in TDFs with a range of resource acquisition strategies. In the model, plants then can dynamically adjust their carbon allocation and nutrient acquisition strategies (e.g. N2-fixing bacteria and mycorrhizal fungi) according to the nutrient limitation status. We test (i) the model's performance against a nutrient gradient of field sites in Costa Rica and (ii) the model's sensitivity to the carbon cost to acquire N through fixation and mycorrhizal relationships. We also report on simulated tree community responses to ongoing field nutrient fertilization experiments. We found that the inclusion of the N2-fixation legume plant functional traits were critical to reproducing community dynamics of Costa Rican field TDF sites and have a large impact on forest biomass. Simulated ecosystem fixation rates matched the magnitude and temporal patterns of field measured fixation. Our results show that symbiotic nitrogen fixation plays an important role in tropical dry forests and biomass accumulation. Also, we suggest that fixation's tight link to the rainy season could result in potential nutrient cycling vulnerabilities with projected rainfall changes.

  3. Biological Evaluations of an Off-Stream Channel, Horizontal Flat-Plate Fish Screen-The Farmers Screen

    USGS Publications Warehouse

    Mesa, Matthew G.; Rose, Brien P.; Copeland, Elizabeth S.

    2010-01-01

    Screens are commonly installed at water diversion sites to reduce entrainment of fish. Recently, the Farmers Irrigation District in Hood River, Oregon, developed a new flat-plate screen design that offers passive operation and may result in reduced operation and installation costs to irrigators. To evaluate the performance (its biological effect on fish) of this type of screen, two size classes of juvenile coho salmon (Oncorhynchus kistuch) were released over a small version of this screen in the field-the Herman Creek screen. The performance of the screen was evaluated over a range of inflow [0.02 to 0.42 m3/s (cubic meters per second)] and diversion flows (0.02 to 0.34 m3/s) at different weir wall heights. The mean approach velocities for the screen ranged from 0 to 5 cm/s (centimeters per second) and mean sweeping velocities ranged from 36 to 178 cm/s. Water depths over the screen surface ranged from 1 to 25 centimeters and were directly related to weir wall height and inflow. Passage of juvenile coho salmon over the screen under a variety of hydraulic conditions did not severely injure them or cause delayed mortality. For all fish, the mean percentage of body surface area that was injured after passage over the screen ranged from about 0.4 to 3.0%. This occurred even though many fish contacted the screen surface during passage. No fish were observed becoming impinged on the screen surface (greater than 1 second contact with the screen). When operated within its design criteria (diversion flows of about 0.28 m3/s), the screen provided safe and effective downstream passage of juvenile salmonids under a variety of hydraulic conditions. However, we do not recommend operating the screen at inflows less than 0.14 m3/s (5 ft3/s) because water depth can get quite shallow and the screen can completely dewater, particularly at very low flows.

  4. Progress Towards an Interdisciplinary Science of Plant Phenology: Building Predictions Across Space, Time and Species Diversity

    NASA Technical Reports Server (NTRS)

    Wolkovich, Elizabeth M.; Cook, Benjamin I.; Davies, T. Jonathan

    2013-01-01

    Climate change has brought renewed interest in the study of plant phenology - the timing of life history events. Data on shifting phenologies with warming have accumulated rapidly, yet research has been comparatively slow to explain the diversity of phenological responses observed across latitudes, growing seasons and species. Here, we outline recent efforts to synthesize perspectives on plant phenology across the fields of ecology, climate science and evolution. We highlight three major axes that vary among these disciplines: relative focus on abiotic versus biotic drivers of phenology, on plastic versus genetic drivers of intraspecific variation, and on cross-species versus autecological approaches. Recent interdisciplinary efforts, building on data covering diverse species and climate space, have found a greater role of temperature in controlling phenology at higher latitudes and for early-flowering species in temperate systems. These efforts have also made progress in understanding the tremendous diversity of responses across species by incorporating evolutionary relatedness, and linking phenological flexibility to invasions and plant performance. Future research with a focus on data collection in areas outside the temperate mid-latitudes and across species' ranges, alongside better integration of how risk and investment shape plant phenology, offers promise for further progress.

  5. Determination of Genetic Diversity in Chilo partellus, Busseola fusca, and Spodoptera frugiperda Infesting Sugarcane in Southern Malawi Using DNA Barcodes.

    PubMed

    Kasambala Donga, Trust; Meadow, Richard

    2018-06-22

    Sugarcane is one of the most valuable crops in the world. Native and exotic Lepidopteran stemborers significantly limit sugarcane production. However, the identity and genetic diversity of stemborers infesting sugarcane in Malawi is unknown. The main objectives for this study were to identify and determine genetic diversity in stemborers infesting sugarcane in Malawi. We conducted field surveys between June 2016 and March 2017 in the Lower Shire Valley district of Chikwawa and Nsanje, southern Malawi. Molecular identification was based amplification the partial cytochrome oxidase subunit I (COI) gene region. Phylogenetic trees for sequences were generated and published GenBank accessions for each species were constructed. We found that Malawi Busseola fusca (Lepidoptera: Noctuidae) specimens belonged to clade II, Spodoptera frugiperda sp. 1 (Lepidoptera: Noctuidae) and Chilo partellus (Lepidoptera: Crambidae) were infesting sugarcane. Interspecific divergence ranged from 8.7% to 15.3%. Intraspecific divergence was highest for B. fusca , 3.6%. There were eight haplotypes for B. fusca , three for S. frugiperda and three for C. partellus . The importance of accurate species identification and genetic diversity on stemborer management is presented.

  6. Shrub range expansion alters diversity and distribution of soil fungal communities across an alpine elevation gradient.

    PubMed

    Collins, Courtney G; Stajich, Jason E; Weber, Sören E; Pombubpa, Nuttapon; Diez, Jeffrey M

    2018-04-19

    Global climate and land use change are altering plant and soil microbial communities worldwide, particularly in arctic and alpine biomes where warming is accelerated. The widespread expansion of woody shrubs into historically herbaceous alpine plant zones is likely to interact with climate to affect soil microbial community structure and function; however, our understanding of alpine soil ecology remains limited. This study aimed to (i) determine whether the diversity and community composition of soil fungi vary across elevation gradients and to (ii) assess the impact of woody shrub expansion on these patterns. In the White Mountains of California, sagebrush (Artemisia rothrockii) shrubs have been expanding upwards into alpine areas since 1960. In this study, we combined observational field data with a manipulative shrub removal experiment along an elevation transect of alpine shrub expansion. We utilized next-generation sequencing of the ITS1 region for fungi and joint distribution modelling to tease apart effects of the environment and intracommunity interactions on soil fungi. We found that soil fungal diversity declines and community composition changes with increasing elevation. Both abiotic factors (primarily soil moisture and soil organic C) and woody sagebrush range expansion had significant effects on these patterns. However, fungal diversity and relative abundance had high spatial variation, overwhelming the predictive power of vegetation type, elevation and abiotic soil conditions at the landscape scale. Finally, we observed positive and negative associations among fungal taxa which may be important in structuring community responses to global change. © 2018 John Wiley & Sons Ltd.

  7. High-precision genetic mapping of behavioral traits in the diversity outbred mouse population

    PubMed Central

    Logan, R W; Robledo, R F; Recla, J M; Philip, V M; Bubier, J A; Jay, J J; Harwood, C; Wilcox, T; Gatti, D M; Bult, C J; Churchill, G A; Chesler, E J

    2013-01-01

    Historically our ability to identify genetic variants underlying complex behavioral traits in mice has been limited by low mapping resolution of conventional mouse crosses. The newly developed Diversity Outbred (DO) population promises to deliver improved resolution that will circumvent costly fine-mapping studies. The DO is derived from the same founder strains as the Collaborative Cross (CC), including three wild-derived strains. Thus the DO provides more allelic diversity and greater potential for discovery compared to crosses involving standard mouse strains. We have characterized 283 male and female DO mice using open-field, light–dark box, tail-suspension and visual-cliff avoidance tests to generate 38 behavioral measures. We identified several quantitative trait loci (QTL) for these traits with support intervals ranging from 1 to 3 Mb in size. These intervals contain relatively few genes (ranging from 5 to 96). For a majority of QTL, using the founder allelic effects together with whole genome sequence data, we could further narrow the positional candidates. Several QTL replicate previously published loci. Novel loci were also identified for anxiety- and activity-related traits. Half of the QTLs are associated with wild-derived alleles, confirming the value to behavioral genetics of added genetic diversity in the DO. In the presence of wild-alleles we sometimes observe behaviors that are qualitatively different from the expected response. Our results demonstrate that high-precision mapping of behavioral traits can be achieved with moderate numbers of DO animals, representing a significant advance in our ability to leverage the mouse as a tool for behavioral genetics PMID:23433259

  8. Field-trip guides to selected volcanoes and volcanic landscapes of the western United States

    USGS Publications Warehouse

    ,

    2017-06-23

    The North American Cordillera is home to a greater diversity of volcanic provinces than any comparably sized region in the world. The interplay between changing plate-margin interactions, tectonic complexity, intra-crustal magma differentiation, and mantle melting have resulted in a wealth of volcanic landscapes.  Field trips in this guide book collection (published as USGS Scientific Investigations Report 2017–5022) visit many of these landscapes, including (1) active subduction-related arc volcanoes in the Cascade Range; (2) flood basalts of the Columbia Plateau; (3) bimodal volcanism of the Snake River Plain-Yellowstone volcanic system; (4) some of the world’s largest known ignimbrites from southern Utah, central Colorado, and northern Nevada; (5) extension-related volcanism in the Rio Grande Rift and Basin and Range Province; and (6) the eastern Sierra Nevada featuring Long Valley Caldera and the iconic Bishop Tuff.  Some of the field trips focus on volcanic eruptive and emplacement processes, calling attention to the fact that the western United States provides opportunities to examine a wide range of volcanological phenomena at many scales.The 2017 Scientific Assembly of the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) in Portland, Oregon, was the impetus to update field guides for many of the volcanoes in the Cascades Arc, as well as publish new guides for numerous volcanic provinces and features of the North American Cordillera. This collection of guidebooks summarizes decades of advances in understanding of magmatic and tectonic processes of volcanic western North America. These field guides are intended for future generations of scientists and the general public as introductions to these fascinating areas; the hope is that the general public will be enticed toward further exploration and that scientists will pursue further field-based research.

  9. Non-destructive assessment of grapevine water status in the field using a portable NIR spectrophotometer.

    PubMed

    Tardaguila, Javier; Fernández-Novales, Juan; Gutiérrez, Salvador; Diago, Maria Paz

    2017-08-01

    Until now, the majority of methods employed to assess grapevine water status have been destructive, time-intensive, costly and provide information of a limited number of samples, thus the ability of revealing within-field water status variability is reduced. The goal of this work was to evaluate the capability of non-invasive, portable near infrared (NIR) spectroscopy acquired in the field, to assess the grapevine water status in diverse varieties, grown under different environmental conditions, in a fast and reliable way. The research was conducted 2 weeks before harvest in 2012, in two commercial vineyards, planted with eight different varieties. Spectral measurements were acquired in the field on the adaxial and abaxial sides of 160 individual leaves (20 leaves per variety) using a commercially available handheld spectrophotometer (1600-2400 nm). Principal component analysis (PCA) and modified partial least squares (MPLS) were used to interpret the spectra and to develop reliable prediction models for stem water potential (Ψ s ) (cross-validation correlation coefficient (r cv ) ranged from 0.77 to 0.93, and standard error of cross validation (SECV) ranged from 0.10 to 0.23), and leaf relative water content (RWC) (r cv ranged from 0.66 to 0.81, and SECV between 1.93 and 3.20). The performance differences between models built from abaxial and adaxial-acquired spectra is also discussed. The capability of non-invasive NIR spectroscopy to reliably assess the grapevine water status under field conditions was proved. This technique can be a suitable and promising tool to appraise within-field variability of plant water status, helpful to define optimised irrigation strategies in the wine industry. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  10. A global synthesis of the effects of diversified farming systems on arthropod diversity within fields and across agricultural landscapes.

    PubMed

    Lichtenberg, Elinor M; Kennedy, Christina M; Kremen, Claire; Batáry, Péter; Berendse, Frank; Bommarco, Riccardo; Bosque-Pérez, Nilsa A; Carvalheiro, Luísa G; Snyder, William E; Williams, Neal M; Winfree, Rachael; Klatt, Björn K; Åström, Sandra; Benjamin, Faye; Brittain, Claire; Chaplin-Kramer, Rebecca; Clough, Yann; Danforth, Bryan; Diekötter, Tim; Eigenbrode, Sanford D; Ekroos, Johan; Elle, Elizabeth; Freitas, Breno M; Fukuda, Yuki; Gaines-Day, Hannah R; Grab, Heather; Gratton, Claudio; Holzschuh, Andrea; Isaacs, Rufus; Isaia, Marco; Jha, Shalene; Jonason, Dennis; Jones, Vincent P; Klein, Alexandra-Maria; Krauss, Jochen; Letourneau, Deborah K; Macfadyen, Sarina; Mallinger, Rachel E; Martin, Emily A; Martinez, Eliana; Memmott, Jane; Morandin, Lora; Neame, Lisa; Otieno, Mark; Park, Mia G; Pfiffner, Lukas; Pocock, Michael J O; Ponce, Carlos; Potts, Simon G; Poveda, Katja; Ramos, Mariangie; Rosenheim, Jay A; Rundlöf, Maj; Sardiñas, Hillary; Saunders, Manu E; Schon, Nicole L; Sciligo, Amber R; Sidhu, C Sheena; Steffan-Dewenter, Ingolf; Tscharntke, Teja; Veselý, Milan; Weisser, Wolfgang W; Wilson, Julianna K; Crowder, David W

    2017-11-01

    Agricultural intensification is a leading cause of global biodiversity loss, which can reduce the provisioning of ecosystem services in managed ecosystems. Organic farming and plant diversification are farm management schemes that may mitigate potential ecological harm by increasing species richness and boosting related ecosystem services to agroecosystems. What remains unclear is the extent to which farm management schemes affect biodiversity components other than species richness, and whether impacts differ across spatial scales and landscape contexts. Using a global metadataset, we quantified the effects of organic farming and plant diversification on abundance, local diversity (communities within fields), and regional diversity (communities across fields) of arthropod pollinators, predators, herbivores, and detritivores. Both organic farming and higher in-field plant diversity enhanced arthropod abundance, particularly for rare taxa. This resulted in increased richness but decreased evenness. While these responses were stronger at local relative to regional scales, richness and abundance increased at both scales, and richness on farms embedded in complex relative to simple landscapes. Overall, both organic farming and in-field plant diversification exerted the strongest effects on pollinators and predators, suggesting these management schemes can facilitate ecosystem service providers without augmenting herbivore (pest) populations. Our results suggest that organic farming and plant diversification promote diverse arthropod metacommunities that may provide temporal and spatial stability of ecosystem service provisioning. Conserving diverse plant and arthropod communities in farming systems therefore requires sustainable practices that operate both within fields and across landscapes. © 2017 John Wiley & Sons Ltd.

  11. CHARMM Force-Fields with Modified Polyphosphate Parameters Allow Stable Simulation of the ATP-Bound Structure of Ca(2+)-ATPase.

    PubMed

    Komuro, Yasuaki; Re, Suyong; Kobayashi, Chigusa; Muneyuki, Eiro; Sugita, Yuji

    2014-09-09

    Adenosine triphosphate (ATP) is an indispensable energy source in cells. In a wide variety of biological phenomena like glycolysis, muscle contraction/relaxation, and active ion transport, chemical energy released from ATP hydrolysis is converted to mechanical forces to bring about large-scale conformational changes in proteins. Investigation of structure-function relationships in these proteins by molecular dynamics (MD) simulations requires modeling of ATP in solution and ATP bound to proteins with accurate force-field parameters. In this study, we derived new force-field parameters for the triphosphate moiety of ATP based on the high-precision quantum calculations of methyl triphosphate. We tested our new parameters on membrane-embedded sarcoplasmic reticulum Ca(2+)-ATPase and four soluble proteins. The ATP-bound structure of Ca(2+)-ATPase remains stable during MD simulations, contrary to the outcome in shorter simulations using original parameters. Similar results were obtained with the four ATP-bound soluble proteins. The new force-field parameters were also tested by investigating the range of conformations sampled during replica-exchange MD simulations of ATP in explicit water. Modified parameters allowed a much wider range of conformational sampling compared with the bias toward extended forms with original parameters. A diverse range of structures agrees with the broad distribution of ATP conformations in proteins deposited in the Protein Data Bank. These simulations suggest that the modified parameters will be useful in studies of ATP in solution and of the many ATP-utilizing proteins.

  12. Assessing diversity of prairie plants using remote sensing

    NASA Astrophysics Data System (ADS)

    Gamon, J. A.; Wang, R.

    2017-12-01

    Biodiversity loss endangers ecosystem services and is considered as a global change that may generate unacceptable environmental consequences for the Earth system. Global biodiversity observations are needed to provide a better understanding of biodiversity - ecosystem services relationships and to provide a stronger foundation for conserving the Earth's biodiversity. While remote sensing metrics have been applied to estimate α biodiversity directly through optical diversity, a better understanding of the mechanisms behind the optical diversity-biodiversity relationship is needed. We designed a series of experiments at Cedar Creek Ecosystem Science Reserve, MN, to investigate the scale dependence of optical diversity and explore how species richness, evenness, and composition affect optical diversity. We collected hyperspectral reflectance of 16 prairie species using both a full-range field spectrometer fitted with a leaf clip, and an imaging spectrometer carried by a tram system to simulate plot-level images with different species richness, evenness, and composition. Two indicators of spectral diversity were explored: the coefficient of variation (CV) of spectral reflectance in space, and spectral classification using a Partial Least Squares Discriminant Analysis (PLS-DA). Our results showed that sampling methods (leaf clip-derived data vs. image-derived data) affected the optical diversity estimation. Both optical diversity indices were affected by species richness and evenness (P<0.001 for each case). At fine spatial scales, species composition also had a substantial influence on optical diversity. CV was sensitive to the background soil influence, but the spectral classification method was insensitive to background. These results provide a critical foundation for assessing biodiversity using imaging spectrometry and these findings can be used to guide regional studies of biodiversity estimation using high spatial and spectral resolution remote sensing.

  13. Agriculture shapes the trophic niche of a bat preying on multiple pest arthropods across Europe: Evidence from DNA metabarcoding.

    PubMed

    Aizpurua, Ostaizka; Budinski, Ivana; Georgiakakis, Panagiotis; Gopalakrishnan, Shyam; Ibañez, Carlos; Mata, Vanessa; Rebelo, Hugo; Russo, Danilo; Szodoray-Parádi, Farkas; Zhelyazkova, Violeta; Zrncic, Vida; Gilbert, M Thomas P; Alberdi, Antton

    2018-02-01

    The interaction between agricultural production and wildlife can shape, and even condition, the functioning of both systems. In this study, we i) explored the degree to which a widespread European bat, namely the common bent-wing bat Miniopterus schreibersii, consumes crop-damaging insects at a continental scale, and ii) tested whether its dietary niche is shaped by the extension and type of agricultural fields. We employed a dual-primer DNA metabarcoding approach to characterize arthropod 16S and COI DNA sequences within bat faecal pellets collected across 16 Southern European localities, to first characterize the bat species' dietary niche, second measure the incidence of agricultural pests across their ranges and third assess whether geographical dietary variation responds to climatic, landscape diversity, agriculture type and vegetation productivity factors. We detected 12 arthropod orders, among which lepidopterans were predominant. We identified >200 species, 44 of which are known to cause agricultural damage. Pest species were detected at all but one sampling site and in 94% of the analysed samples. Furthermore, the dietary diversity of M. schreibersii exhibited a negative linear relation with the area of intensive agricultural fields, thus suggesting crops restrict the dietary niche of bats to prey taxa associated with agricultural production within their foraging range. Overall, our results imply that M. schreibersii might be a valuable asset for biological pest suppression in a variety of agricultural productions and highlight the dynamic interplay between wildlife and agricultural systems. © 2017 John Wiley & Sons Ltd.

  14. Field-based evaluations of horizontal flat-plate fish screens, II: Testing of a unique off-stream channel device - The Farmers Screen

    USGS Publications Warehouse

    Mesa, Matthew G.; Rose, Brien P.; Copeland, Elizabeth S.

    2012-01-01

    Screens are installed at water diversion sites to reduce entrainment of fish. Recently, the Farmers Irrigation District (Oregon) developed a unique flat-plate screen (the “Farmers Screen”) that operates passively and may offer reduced installation and operating costs. To evaluate the effectiveness of this screen on fish, we conducted two separate field experiments. First, juvenile coho salmon Oncorhynchus kisutch were released over a working version of this screen under a range of inflows (0.02–0.42 m3/s) and diversion flows (0.02–0.34 m3/s) at different water depths. Mean approach velocities ranged from 0 to 5 cm/s and sweeping velocities ranged from 36 to 178 cm/s. Water depths over the screen surface ranged from 1 to 25 cm and were directly related to inflow. Passage of fish over the screen under these conditions did not severely injure them or cause delayed mortality, and no fish were observed becoming impinged on the screen surface. Second, juvenile coho salmon and steelhead O. mykiss were released at the upstream end of a 34-m flume and allowed to volitionally move downstream and pass over a 3.5-m section of the Farmers Screen to determine whether fish would refuse to pass over the screen after encountering its leading edge. For coho salmon, 75–95% of the fish passed over the screen within 5 min and 82–98% passed within 20 min, depending on hydraulic conditions. For steelhead, 47–90% of the fish passed over the screen within 5 min and 79–95% passed within 20 min. Our results indicate that when operated within its design criteria, the Farmers Screen provides safe and efficient downstream passage of juvenile salmonids under a variety of hydraulic conditions.

  15. An overview of turbulence compensation

    NASA Astrophysics Data System (ADS)

    Schutte, Klamer; van Eekeren, Adam W. M.; Dijk, Judith; Schwering, Piet B. W.; van Iersel, Miranda; Doelman, Niek J.

    2012-09-01

    In general, long range visual detection, recognition and identification are hampered by turbulence caused by atmospheric conditions. Much research has been devoted to the field of turbulence compensation. One of the main advantages of turbulence compensation is that it enables visual identification over larger distances. In many (military) scenarios this is of crucial importance. In this paper we give an overview of several software and hardware approaches to compensate for the visual artifacts caused by turbulence. These approaches are very diverse and range from the use of dedicated hardware, such as adaptive optics, to the use of software methods, such as deconvolution and lucky imaging. For each approach the pros and cons are given and it is indicated for which type of scenario this approach is useful. In more detail we describe the turbulence compensation methods TNO has developed in the last years and place them in the context of the different turbulence compensation approaches and TNO's turbulence compensation roadmap. Furthermore we look forward and indicate the upcoming challenges in the field of turbulence compensation.

  16. Turbulence compensation: an overview

    NASA Astrophysics Data System (ADS)

    van Eekeren, Adam W. M.; Schutte, Klamer; Dijk, Judith; Schwering, Piet B. W.; van Iersel, Miranda; Doelman, Niek J.

    2012-06-01

    In general, long range visual detection, recognition and identification are hampered by turbulence caused by atmospheric conditions. Much research has been devoted to the field of turbulence compensation. One of the main advantages of turbulence compensation is that it enables visual identification over larger distances. In many (military) scenarios this is of crucial importance. In this paper we give an overview of several software and hardware approaches to compensate for the visual artifacts caused by turbulence. These approaches are very diverse and range from the use of dedicated hardware, such as adaptive optics, to the use of software methods, such as deconvolution and lucky imaging. For each approach the pros and cons are given and it is indicated for which scenario this approach is useful. In more detail we describe the turbulence compensation methods TNO has developed in the last years and place them in the context of the different turbulence compensation approaches and TNO's turbulence compensation roadmap. Furthermore we look forward and indicate the upcoming challenges in the field of turbulence compensation.

  17. Toward a psychology of human-animal relations.

    PubMed

    Amiot, Catherine E; Bastian, Brock

    2015-01-01

    Nonhuman animals are ubiquitous to human life, and permeate a diversity of social contexts by providing humans with food and clothing, serving as participants in research, improving healing, and offering entertainment, leisure, and companionship. Despite the impact that animals have on human lives and vice versa, the field of psychology has barely touched upon the topic of human-animal relations as an important domain of human activity. We review the current state of research on human-animal relations, showing how this body of work has implications for a diverse range of psychological themes including evolutionary processes, development, normative factors, gender and individual differences, health and therapy, and intergroup relations. Our aim is to highlight human-animal relations as a domain of human life that merits theoretical and empirical attention from psychology as a discipline. PsycINFO Database Record (c) 2015 APA, all rights reserved.

  18. Modeling a synthetic multicellular clock: Repressilators coupled by quorum sensing

    PubMed Central

    Garcia-Ojalvo, Jordi; Elowitz, Michael B.; Strogatz, Steven H.

    2004-01-01

    Diverse biochemical rhythms are generated by thousands of cellular oscillators that somehow manage to operate synchronously. In fields ranging from circadian biology to endocrinology, it remains an exciting challenge to understand how collective rhythms emerge in multicellular structures. Using mathematical and computational modeling, we study the effect of coupling through intercell signaling in a population of Escherichia coli cells expressing a synthetic biological clock. Our results predict that a diverse and noisy community of such genetic oscillators interacting through a quorum-sensing mechanism should self-synchronize in a robust way, leading to a substantially improved global rhythmicity in the system. As such, the particular system of coupled genetic oscillators considered here might be a good candidate to provide the first quantitative example of a synchronization transition in a population of biological oscillators. PMID:15256602

  19. BacDive--The Bacterial Diversity Metadatabase in 2016.

    PubMed

    Söhngen, Carola; Podstawka, Adam; Bunk, Boyke; Gleim, Dorothea; Vetcininova, Anna; Reimer, Lorenz Christian; Ebeling, Christian; Pendarovski, Cezar; Overmann, Jörg

    2016-01-04

    BacDive-the Bacterial Diversity Metadatabase (http://bacdive.dsmz.de) provides strain-linked information about bacterial and archaeal biodiversity. The range of data encompasses taxonomy, morphology, physiology, sampling and concomitant environmental conditions as well as molecular biology. The majority of data is manually annotated and curated. Currently (with release 9/2015), BacDive covers 53 978 strains. Newly implemented RESTful web services provide instant access to the content in machine-readable XML and JSON format. Besides an overall increase of data content, BacDive offers new data fields and features, e.g. the search for gene names, plasmids or 16S rRNA in the advanced search, as well as improved linkage of entries to external life science web resources. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  20. Differing forms, differing purposes: A typology of health impact assessment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harris-Roxas, Ben, E-mail: b.harris-roxas@unsw.edu.au; Harris, Elizabeth, E-mail: e.harris@unsw.edu.a

    2011-07-15

    There is currently considerable diversity in health impact assessment (HIA) practice internationally. Historically this diversity has been described as simple dichotomies, for example the differences between HIAs of projects and policies. However these distinctions have failed to adequately describe the differences that can be observed between different forms of HIAs. This paper describes the three historical and disciplinary fields from which HIA has emerged - environmental health, a social view of health, and health equity. It also puts forward a typology of four different forms of HIA that can be observed in current HIA practice: mandated, decision-support, advocacy, and community-ledmore » HIAs. This paper argues that these different forms of HIA serve different purposes and are not necessarily in competition; rather they allow HIA to be responsive to a range of population health concerns and purposes.« less

  1. Translating Population Difference: The Use and Re-Use of Genetic Ancestry in Brazilian Cancer Genetics

    PubMed Central

    Gibbon, Sahra

    2016-01-01

    ABSTRACT In the past ten years, there has been an expansion of scientific interest in population genetics linked to both understanding histories of human migration and the way that population difference and diversity may account for and/or be implicated in health and disease. In this article, I examine how particular aspects of a globalizing research agenda related to population differences and genetic ancestry are taken up in locally variant ways in the nascent field of Brazilian cancer genetics. Drawing on a broad range of ethnographic data from clinical and nonclinical contexts in the south of Brazil, I examine the ambiguities that attention to genetic ancestry generates, so revealing the disjunctured and diverse ways a global research agenda increasingly orientated to questions of population difference and genetic ancestry is being used and reused. PMID:26452039

  2. Plasmodium vivax merozoite surface protein-3 alpha: a high-resolution marker for genetic diversity studies.

    PubMed

    Prajapati, Surendra Kumar; Joshi, Hema; Valecha, Neena

    2010-06-01

    Malaria, an ancient human infectious disease caused by five species of Plasmodium, among them Plasmodium vivax is the most widespread human malaria species and causes huge morbidity to its host. Identification of genetic marker to resolve higher genetic diversity for an ancient origin organism is a crucial task. We have analyzed genetic diversity of P. vivax field isolates using highly polymorphic antigen gene merozoite surface protein-3 alpha (msp-3 alpha) and assessed its suitability as high-resolution genetic marker for population genetic studies. 27 P. vivax field isolates collected during chloroquine therapeutic efficacy study at Chennai were analyzed for genetic diversity. PCR-RFLP was employed to assess the genetic variations using highly polymorphic antigen gene msp-3 alpha. We observed three distinct PCR alleles at msp-3 alpha, and among them allele A showed significantly high frequency (53%, chi2 = 8.22, p = 0.001). PCR-RFLP analysis revealed 14 and 17 distinct RFLP patterns for Hha1 and Alu1 enzymes respectively. Further, RFLP analysis revealed that allele A at msp-3 alpha is more diverse in the population compared with allele B and C. Combining Hha1 and Alu1 RFLP patterns revealed 21 distinct genotypes among 22 isolates reflects higher diversity resolution power of msp-3 alpha in the field isolates. P. vivax isolates from Chennai region revealed substantial amount of genetic diversity and comparison of allelic diversity with other antigen genes and microsatellites suggesting that msp-3 alpha could be a high-resolution marker for genetic diversity studies among P. vivax field isolates.

  3. Is plant temporal beta diversity of field margins related to changes in management practices?

    NASA Astrophysics Data System (ADS)

    Alignier, Audrey; Baudry, Jacques

    2016-08-01

    Field margins have considerable ecological significance in agriculture-dominated landscapes by supporting biodiversity and associated services. However, agricultural changes during mid-20th century led to their drastic loss with a serious threat for biodiversity. Using time-series data, we aimed to get better insights into processes underlying plant patterns of field margins through time by i) quantifying plant temporal beta diversity components, ii) assessing whether the observed changes in plant communities can be related to changes in management practices applied to field margins. During the springs of 1994, 1998 and 2001, we surveyed plant communities and management practices of the same 116 field margins in three contrasted landscapes. We estimated temporal beta diversity in plant communities and partitioned it into its two dissimilarity resultant components, accounting for replacement of species (i.e. turnover) and for the nested gain or loss of species (i.e. nestedness). We then tested whether the observed changes in plant communities between 1994 and 1998 and, between 1998 and 2001 were related to changes in management practices using linear models. Plant communities of field margins exhibited strong temporal beta diversity dominated by turnover. Temporal turnover in plant communities was partly related to changes in management practices, i.e., a decrease of grazing concomitant to an increase of herbicide spraying. However, relationships were not consistent between all landscape contexts nor time period, suggesting that other unmeasured deterministic or stochastic processes could be driving the observed plant patterns. Taken together, our results suggest that maintaining a wide diversity of field margins with contrasted management contribute to maintaining plant diversity at a landscape scale. They underline the value of investigating plant temporal diversity patterns using time-series data and thus, the need to develop long-term studies making it possible to understand ecological processes shaping plant communities in agricultural landscapes.

  4. Electrically Guided Assembly of Colloidal Particles

    NASA Astrophysics Data System (ADS)

    Ristenpart, W. D.; Aksay, I. A.; Saville, D. A.

    2002-11-01

    In earlier work it was shown that the strength and frequency of an applied electric field alters the dynamic arrangement of particles on an electrode. Two-dimensional 'gas,' 'liquid' and 'solid' arrangements were formed, depending on the field strength and frequency. Since the particles are similarly charged, yet migrate over large distances under the influence of steady or oscillatory fields, it is clear that both hydrodynamic and electrical processes are involved. Here we report on an extensive study of electrically induced ordering in a parallel electrode cell. First, we discuss the kinetics of aggregation in a DC field as measured using video microscopy and digital image analysis. Rate constants were determined as a function of applied electric field strength and particle zeta potential. The kinetic parameters are compared to models based on electrohydrodynamic and electroosmotic fluid flow mechanisms Second, using monodisperse micron-sized particles, we examined the average interparticle spacing over a wide range of applied frequencies and field strengths. Variation of these parameters allows formation of closely-spaced arrangements and ordered arrays of widely separated particles. We find that there is a strong dependence on frequency, but there is surprisingly little influence of the electric field strength past a small threshold. Last, we present experiments with binary suspensions of similarly sized particles with negative but unequal surface potentials. A long-range lateral attraction is observed in an AC field. Depending on the frequency, this attractive interaction results in a diverse set of aggregate morphologies, including superstructured hexagonal lattices. These results are discussed in terms of induced dipole-dipole interactions and electrohydrodynamic flow. Finally, we explore the implications for practical applications.

  5. Taxocoenosis and distribution of nektonic fauna in the rice fields of Kashmir (J and K) India.

    PubMed

    Bahaar, S W N; Bhat, G A

    2011-04-15

    Present study attempts to identify the taxocoenosis and distribution of nektonic fauna harbouring the rice field ecosystems of Kashmir. The main objective of the study was to provide an overview of the nektonic community composition and physicochemical characteristics of flood waters. 6 sites were selected in Kupwara, Bandipora, Budgam, Srinagar, Pulwama and Anantnag districts of valley Kashmir. A total of 26 taxa belonging to 13 different orders were reported during the study which commenced through 2 consecutive crop cycles. The taxocoenosis was dominated by Coleoptera (10 taxa) followed by Hemiptera (3 taxa), Diptera (2 taxa), Diplostraca (2 taxa), Acarina, Anostraca, Anura, Amphipoda, Basommatophora, Cypriniformes, Cyprinodontiformes, Odonata and Pulmonata (1 taxa each). Diversity was calculated using Simpsons Index (D), Simpsons Index of Diversity (1-D), Simpsons Reciprocal Index (1/D), Shannon-Weiner Index (H'), Margalef Richness Index (d) and Evenness Index (e). Kupwara (34 degrees 02'N; 74 degrees 16'E) formed the most diverse site registering a total of 2384 individuals belonging to 24 taxa. A perusal of the primary data related to the physicochemical attributes of flood waters exhibited that average water temperature varied between 19-30 degrees C, average air temperature varied between 21 and 33 degrees C. pH depicted a variation between 6.0 and 9.0, Dissolved Oxygen varied between a minimum of 1.0 mg L(-1) and a maximum of 10 mg L(-1). Free CO2 ranged between 0 mg L(-1) and 6.1 mg(-1). The results pressed the need for recognizing and preserving rice fields as potential habitats for organisms that have successfully adapted to the highly manipulated and eutrophic conditions of rice paddies.

  6. Implications of invasion by Juniperus virginiana on small mammals in the southern Great Plains

    USGS Publications Warehouse

    Horncastle, V.J.; Hellgren, E.C.; Mayer, P.M.; Ganguli, A.C.; Engle, David M.; Leslie, David M.

    2005-01-01

    Changes in landscape cover in the Great Plains are resulting from the range expansion and invasion of eastern red cedar (Juniperus virginiana). By altering the landscape and local vegetation, red cedar is changing the structure and function of habitat for small mammals. We examined effects of invasion by eastern red cedar on small mammals in 3 plant communities (tallgrass prairie, old field, and cross-timbers forest) in the cross-timbers ecoregion in Oklahoma. We sampled small mammals seasonally from May 2001 to August 2002 by using Sherman live traps and mark-recapture techniques on 3.24-ha, 450-trap grids in each plant community. We sampled vegetation in two hundred twenty-five 12 x 12-m cells within each grid. The structure of the small-mammal community differed among the 3 habitat types, with higher species diversity and richness in the tallgrass-prairie and old-field sites. Overall, the small-mammal community shifted along a gradient of increasing eastern red cedar. In the old-field and tallgrass-prairie plots, occurrence of grassland mammals decreased with increasing red cedar, whereas only 1 woodland mammal species increased. In the cross-timbers forest site, percent woody cover (<1 m in height), rather than cover of red cedar, was the most important factor affecting woodland mammal species. Examination of our data suggests that an increase in overstory cover from 0% to 30% red cedar can change a species-rich prairie community to a depauperate community dominated by 1 species, Peromyscus leucopus. Losses in species diversity and changes in mammal distribution paralleled those seen in avian communities invaded by eastern red cedar. Our results highlight ecological effects of invasion by eastern red cedar on diversity and function at multiple trophic levels. ?? 2005 American Society of Mammalogists.

  7. Ensuring the security of synthetic biology-towards a 5P governance strategy.

    PubMed

    Kelle, Alexander

    2009-12-01

    Over recent years the label "synthetic biology" has been attached to a number of diverse research and commercial activities, ranging from the search for a minimal cell to the quick delivery of customized genes by DNA synthesis companies. Based on the analysis of biosecurity issues surrounding synthetic biology during the SYNBIOSAFE project, this paper will first provide a rationale for taking security, in addition to safety aspects of this new field, seriously. It will then take stock of the initiatives and measures that have already been taken in this area and will lastly try to map out future areas of activities in order to minimise the security risks emanating from this promising new field of scientific inquiry and technological progress.

  8. Humboldt's spa: microbial diversity is controlled by temperature in geothermal environments

    PubMed Central

    Sharp, Christine E; Brady, Allyson L; Sharp, Glen H; Grasby, Stephen E; Stott, Matthew B; Dunfield, Peter F

    2014-01-01

    Over 200 years ago Alexander von Humboldt (1808) observed that plant and animal diversity peaks at tropical latitudes and decreases toward the poles, a trend he attributed to more favorable temperatures in the tropics. Studies to date suggest that this temperature–diversity gradient is weak or nonexistent for Bacteria and Archaea. To test the impacts of temperature as well as pH on bacterial and archaeal diversity, we performed pyrotag sequencing of 16S rRNA genes retrieved from 165 soil, sediment and biomat samples of 36 geothermal areas in Canada and New Zealand, covering a temperature range of 7.5–99 °C and a pH range of 1.8–9.0. This represents the widest ranges of temperature and pH yet examined in a single microbial diversity study. Species richness and diversity indices were strongly correlated to temperature, with R2 values up to 0.62 for neutral–alkaline springs. The distributions were unimodal, with peak diversity at 24 °C and decreasing diversity at higher and lower temperature extremes. There was also a significant pH effect on diversity; however, in contrast to previous studies of soil microbial diversity, pH explained less of the variability (13–20%) than temperature in the geothermal samples. No correlation was observed between diversity values and latitude from the equator, and we therefore infer a direct temperature effect in our data set. These results demonstrate that temperature exerts a strong control on microbial diversity when considered over most of the temperature range within which life is possible. PMID:24430481

  9. Humboldt's spa: microbial diversity is controlled by temperature in geothermal environments.

    PubMed

    Sharp, Christine E; Brady, Allyson L; Sharp, Glen H; Grasby, Stephen E; Stott, Matthew B; Dunfield, Peter F

    2014-06-01

    Over 200 years ago Alexander von Humboldt (1808) observed that plant and animal diversity peaks at tropical latitudes and decreases toward the poles, a trend he attributed to more favorable temperatures in the tropics. Studies to date suggest that this temperature-diversity gradient is weak or nonexistent for Bacteria and Archaea. To test the impacts of temperature as well as pH on bacterial and archaeal diversity, we performed pyrotag sequencing of 16S rRNA genes retrieved from 165 soil, sediment and biomat samples of 36 geothermal areas in Canada and New Zealand, covering a temperature range of 7.5-99 °C and a pH range of 1.8-9.0. This represents the widest ranges of temperature and pH yet examined in a single microbial diversity study. Species richness and diversity indices were strongly correlated to temperature, with R(2) values up to 0.62 for neutral-alkaline springs. The distributions were unimodal, with peak diversity at 24 °C and decreasing diversity at higher and lower temperature extremes. There was also a significant pH effect on diversity; however, in contrast to previous studies of soil microbial diversity, pH explained less of the variability (13-20%) than temperature in the geothermal samples. No correlation was observed between diversity values and latitude from the equator, and we therefore infer a direct temperature effect in our data set. These results demonstrate that temperature exerts a strong control on microbial diversity when considered over most of the temperature range within which life is possible.

  10. The potential of audiomagnetotellurics in the study of geothermal fields: A case study from the northern segment of the La Candelaria Range, northwestern Argentina

    NASA Astrophysics Data System (ADS)

    Barcelona, Hernan; Favetto, Alicia; Peri, Veronica Gisel; Pomposiello, Cristina; Ungarelli, Carlo

    2013-01-01

    Despite its reduced penetration depth, audiomagnetotelluric (AMT) studies can be used to determine a broad range of features related to little studied geothermal fields. This technique requires a stepwise interpretation of results taking into consideration diverse information (e.g. topographic, hydrological, geological and/or structural data) to constrain the characteristics of the study area. In this work, an AMT study was performed at the hot springs in the northern segment of the La Candelaria Range in order to characterize the area at depth. Geometric aspects of the shallow subsurface were determined based on the dimensional and distortion analysis of the impedance tensors. Also, the correlation between structural features and regional strikes allowed us to define two geoelectric domains, useful to determine the controls on fluid circulation. The subsurface resistivity distribution was determined through 1D and 2D models. The patterns of the 1D models were compared with the morpho-structure of the range. Shallow and deep conductive zones were defined and a possible shallow geothermal system scheme proposed. A strong correlation was found between the AMT results and the geological framework of the region, showing the relevance of using AMT in geothermal areas during the early stages of subsurface prospecting.

  11. Morphology and Structure of Ultraluminous Infrared Galaxies at z ≈ 2 in the EGS Field

    NASA Astrophysics Data System (ADS)

    Fang, G. W.; Ma, Z. Y.; Chen, Y.; Kong, X.

    2014-11-01

    Using high-resolution HST WFC3 (Hubble Space Telescope Wide Field Camera 3) F160W imaging from the CANDELS-EGS (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey-Extended Groth Strip) field, we present the morphology analysis of 9 ultraluminous infrared galaxies (ULIRGs) at z≈2. We find a wide range of morphological diversities for these ULIRGs, from spheroid to multiple bright nuclei or diffuse structures, e.g., double nuclei, bridges, dual asymmetries, irregular, or elliptical structures. In quantitative, these sources show a lower Gini coefficient (G) and a higher moment (M_{20}) in the rest-frame optical morphology, compared to the lower redshift counterparts, indicating less concentrated and symmetric spatial distribution of the stellar mass of ULIRGs at z≈2. Moreover, we derive accurate effective radii of these ULIRGs through 2-D profile fitting, which range from 2.4 to 5.8 kpc, with a mean value of (3.9±1.1) kpc. We find that the sizes of these ULIRGs at z≈2 are on average one to two times smaller than those of the local star-forming galaxies with analogous stellar mass. Our results are consistent with those studies at similar redshift and infrared luminosity.

  12. Patterns of Deep-Water Coral Diversity in the Caribbean Basin and Adjacent Southern Waters: An Approach based on Records from the R/V Pillsbury Expeditions

    PubMed Central

    Hernández-Ávila, Iván

    2014-01-01

    The diversity of deep-water corals in the Caribbean Sea was studied using records from oceanographic expeditions performed by the R/V Pillsbury. Sampled stations were sorted according to broad depth ranges and ecoregions and were analyzed in terms of species accumulation curves, variance in the species composition and contributions to alpha, beta and gamma diversity. According to the analysis of species accumulation curves using the Chao2 estimator, more diversity occurs on the continental slope (200–2000 m depth) than on the upper continental shelf (60–200 m depth). In addition to the effect of depth sampling, differences in species composition related to depth ranges were detected. However, the differences between ecoregions are dependent on depth ranges, there were fewer differences among ecoregions on the continental slope than on the upper continental shelf. Indicator species for distinctness of ecoregions were, in general, Alcyonaria and Antipatharia for the upper continental shelf, but also the scleractinians Madracis myriabilis and Cladocora debilis. In the continental slope, the alcyonarian Placogorgia and the scleractinians Stephanocyathus and Fungiacyathus were important for the distinction of ecoregions. Beta diversity was the most important component of gamma diversity in the Caribbean Basin. The contribution of ecoregions to alpha, beta and gamma diversity differed with depth range. On the upper continental shelf, the Southern Caribbean ecoregion contributed substantially to all components of diversity. In contrast, the northern ecoregions contributed substantially to the diversity of the Continental Slope. Strategies for the conservation of deep-water coral diversity in the Caribbean Basin must consider the variation between ecoregions and depth ranges. PMID:24671156

  13. A Field and Classroom Exercise for Measuring the Species Diversity of Freshwater Plankton Communities.

    ERIC Educational Resources Information Center

    Kirby, John M.; Reinking, Larry N.

    1994-01-01

    Utilizing the vast diversity of planktonic communities that exist in local, temperate ponds and lakes, the authors describe a simple exercise that gives students both a field and classroom experience in biodiversity. (ZWH)

  14. French invasive Asian tiger mosquito populations harbor reduced bacterial microbiota and genetic diversity compared to Vietnamese autochthonous relatives

    PubMed Central

    Minard, G.; Tran, F. H.; Van, Van Tran; Goubert, C.; Bellet, C.; Lambert, G.; Kim, Khanh Ly Huynh; Thuy, Trang Huynh Thi; Mavingui, P.; Valiente Moro, C.

    2015-01-01

    The Asian tiger mosquito Aedes albopictus is one of the most significant pathogen vectors of the twenty-first century. Originating from Asia, it has invaded a wide range of eco-climatic regions worldwide. The insect-associated microbiota is now recognized to play a significant role in host biology. While genetic diversity bottlenecks are known to result from biological invasions, the resulting shifts in host-associated microbiota diversity has not been thoroughly investigated. To address this subject, we compared four autochthonous Ae. albopictus populations in Vietnam, the native area of Ae. albopictus, and three populations recently introduced to Metropolitan France, with the aim of documenting whether these populations display differences in host genotype and bacterial microbiota. Population-level genetic diversity (microsatellite markers and COI haplotype) and bacterial diversity (16S rDNA metabarcoding) were compared between field-caught mosquitoes. Bacterial microbiota from the whole insect bodies were largely dominated by Wolbachia pipientis. Targeted analysis of the gut microbiota revealed a greater bacterial diversity in which a fraction was common between French and Vietnamese populations. The genus Dysgonomonas was the most prevalent and abundant across all studied populations. Overall genetic diversities of both hosts and bacterial microbiota were significantly reduced in recently established populations of France compared to the autochthonous populations of Vietnam. These results open up many important avenues of investigation in order to link the process of geographical invasion to shifts in commensal and symbiotic microbiome communities, as such shifts may have dramatic impacts on the biology and/or vector competence of invading hematophagous insects. PMID:26441903

  15. Self-shadowing effects of slim accretion disks in active galactic nuclei: the diverse appearance of the broad-line region

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Jian-Min; Qiu, Jie; Du, Pu

    2014-12-10

    Supermassive black holes in active galactic nuclei (AGNs) undergo a wide range of accretion rates, which lead to diversity of appearance. We consider the effects of anisotropic radiation from accretion disks on the broad-line region (BLR) from the Shakura-Sunyaev regime to slim disks with super-Eddington accretion rates. The geometrically thick funnel of the inner region of slim disks produces strong self-shadowing effects that lead to very strong anisotropy of the radiation field. We demonstrate that the degree of anisotropy of the radiation fields grows with increasing accretion rate. As a result of this anisotropy, BLR clouds receive different spectral energymore » distributions depending on their location relative to the disk, resulting in the diverse observational appearance of the BLR. We show that the self-shadowing of the inner parts of the disk naturally produces two dynamically distinct regions of the BLR, depending on accretion rate. These two regions manifest themselves as kinematically distinct components of the broad Hβ line profile with different line widths and fluxes, which jointly account for the Lorentzian profile generally observed in narrow-line Seyfert 1 galaxies. In the time domain, these two components are expected to reverberate with different time lags with respect to the varying ionizing continuum, depending on the accretion rate and the viewing angle of the observer. The diverse appearance of the BLR due to the anisotropic ionizing energy source can be tested by reverberation mapping of Hβ and other broad emission lines (e.g., Fe II), providing a new tool to diagnose the structure and dynamics of the BLR. Other observational consequences of our model are also explored.« less

  16. How hedge woody species diversity and habitat change is a function of land use history and recent management in a European agricultural landscape.

    PubMed

    McCann, Thomas; Cooper, Alan; Rogers, David; McKenzie, Paul; McErlean, Thomas

    2017-07-01

    European hedged agricultural landscapes provide a range of ecosystem services and are an important component of cultural and biodiversity heritage. This paper investigates the extent of hedges, their woody species diversity (including the influence of historical versus recent hedge origin) and dynamics of change. The rationale is to contribute to an ecological basis for hedge habitat management. Sample sites were allocated based on a multivariate classification of landscape attributes. All field boundaries present in each site were mapped and surveyed in 1998 and 2007. To assess diversity, a list of all woody species was recorded in one standard 30 m linear plot within each hedge. There was a net decrease in hedge habitat extent, mainly as a result of removal, and changes between hedges and other field boundary types due to the development and loss of shrub growth-form. Agricultural intensification, increased rural building, and variation in hedge management practices were the main drivers of change. Hedges surveyed at baseline, which were lost at resurvey, were more species rich than new hedges gained. Hedges coinciding with historical land unit boundaries of likely Early Medieval origin were found to be more species rich. The most frequent woody species in hedges were native, including a high proportion with Fraxinus excelsior, a species under threat from current and emerging plant pests and pathogens. Introduced species were present in circa 30% of hedges. We conclude that since hedge habitat distribution and woody species diversity is a function of ecology and anthropogenic factors, the management of hedges in enclosed agricultural landscapes requires an integrated approach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Digital detection of endonuclease mediated gene disruption in the HIV provirus

    PubMed Central

    Sedlak, Ruth Hall; Liang, Shu; Niyonzima, Nixon; De Silva Feelixge, Harshana S.; Roychoudhury, Pavitra; Greninger, Alexander L.; Weber, Nicholas D.; Boissel, Sandrine; Scharenberg, Andrew M.; Cheng, Anqi; Magaret, Amalia; Bumgarner, Roger; Stone, Daniel; Jerome, Keith R.

    2016-01-01

    Genome editing by designer nucleases is a rapidly evolving technology utilized in a highly diverse set of research fields. Among all fields, the T7 endonuclease mismatch cleavage assay, or Surveyor assay, is the most commonly used tool to assess genomic editing by designer nucleases. This assay, while relatively easy to perform, provides only a semi-quantitative measure of mutation efficiency that lacks sensitivity and accuracy. We demonstrate a simple droplet digital PCR assay that quickly quantitates a range of indel mutations with detection as low as 0.02% mutant in a wild type background and precision (≤6%CV) and accuracy superior to either mismatch cleavage assay or clonal sequencing when compared to next-generation sequencing. The precision and simplicity of this assay will facilitate comparison of gene editing approaches and their optimization, accelerating progress in this rapidly-moving field. PMID:26829887

  18. Principles and applications of polymerase chain reaction in medical diagnostic fields: a review

    PubMed Central

    Valones, Marcela Agne Alves; Guimarães, Rafael Lima; Brandão, Lucas André Cavalcanti; de Souza, Paulo Roberto Eleutério; de Albuquerque Tavares Carvalho, Alessandra; Crovela, Sergio

    2009-01-01

    Recent developments in molecular methods have revolutionized the detection and characterization of microorganisms in a broad range of medical diagnostic fields, including virology, mycology, parasitology, microbiology and dentistry. Among these methods, Polymerase Chain Reaction (PCR) has generated great benefits and allowed scientific advancements. PCR is an excellent technique for the rapid detection of pathogens, including those difficult to culture. Along with conventional PCR techniques, Real-Time PCR has emerged as a technological innovation and is playing an ever-increasing role in clinical diagnostics and research laboratories. Due to its capacity to generate both qualitative and quantitative results, Real-Time PCR is considered a fast and accurate platform. The aim of the present literature review is to explore the clinical usefulness and potential of both conventional PCR and Real-Time PCR assays in diverse medical fields, addressing its main uses and advances. PMID:24031310

  19. Enhanced magnetocaloric effect tuning efficiency in Ni-Mn-Sn alloy ribbons

    NASA Astrophysics Data System (ADS)

    Quintana-Nedelcos, A.; Sánchez Llamazares, J. L.; Daniel-Perez, G.

    2017-11-01

    The present work was undertaken to investigate the effect of microstructure on the magnetic entropy change of Ni50Mn37Sn13 ribbon alloys. Unchanged sample composition and cell parameter of austenite allowed us to study strictly the correlation between the average grain size and the total magnetic field induced entropy change (ΔST). We found that a size-dependent martensitic transformation tuning results in a wide temperature range tailoring (>40 K) of the magnetic entropy change with a reasonably small variation on the peak value of the total field induced entropy change. The peak values varied from 6.0 J kg-1 K-1 to 7.7 J kg-1 K-1 for applied fields up to 2 T. Different tuning efficiencies obtained by diverse MCE tailoring approaches are compared to highlight the advantages of the herein proposed mechanism.

  20. Why interdisciplinary research enriches the study of crime. Comment on "Statistical physics of crime: A review" by M.R. D'Orsogna and M. Perc

    NASA Astrophysics Data System (ADS)

    Donnay, Karsten

    2015-03-01

    The past several years have seen a rapidly growing interest in the use of advanced quantitative methodologies and formalisms adapted from the natural sciences to study a broad range of social phenomena. The research field of computational social science [1,2], for example, uses digital artifacts of human online activity to cast a new light on social dynamics. Similarly, the studies reviewed by D'Orsogna and Perc showcase a diverse set of advanced quantitative techniques to study the dynamics of crime. Methods used range from partial differential equations and self-exciting point processes to agent-based models, evolutionary game theory and network science [3].

  1. MicRhoDE: a curated database for the analysis of microbial rhodopsin diversity and evolution

    PubMed Central

    Boeuf, Dominique; Audic, Stéphane; Brillet-Guéguen, Loraine; Caron, Christophe; Jeanthon, Christian

    2015-01-01

    Microbial rhodopsins are a diverse group of photoactive transmembrane proteins found in all three domains of life and in viruses. Today, microbial rhodopsin research is a flourishing research field in which new understandings of rhodopsin diversity, function and evolution are contributing to broader microbiological and molecular knowledge. Here, we describe MicRhoDE, a comprehensive, high-quality and freely accessible database that facilitates analysis of the diversity and evolution of microbial rhodopsins. Rhodopsin sequences isolated from a vast array of marine and terrestrial environments were manually collected and curated. To each rhodopsin sequence are associated related metadata, including predicted spectral tuning of the protein, putative activity and function, taxonomy for sequences that can be linked to a 16S rRNA gene, sampling date and location, and supporting literature. The database currently covers 7857 aligned sequences from more than 450 environmental samples or organisms. Based on a robust phylogenetic analysis, we introduce an operational classification system with multiple phylogenetic levels ranging from superclusters to species-level operational taxonomic units. An integrated pipeline for online sequence alignment and phylogenetic tree construction is also provided. With a user-friendly interface and integrated online bioinformatics tools, this unique resource should be highly valuable for upcoming studies of the biogeography, diversity, distribution and evolution of microbial rhodopsins. Database URL: http://micrhode.sb-roscoff.fr. PMID:26286928

  2. MicRhoDE: a curated database for the analysis of microbial rhodopsin diversity and evolution.

    PubMed

    Boeuf, Dominique; Audic, Stéphane; Brillet-Guéguen, Loraine; Caron, Christophe; Jeanthon, Christian

    2015-01-01

    Microbial rhodopsins are a diverse group of photoactive transmembrane proteins found in all three domains of life and in viruses. Today, microbial rhodopsin research is a flourishing research field in which new understandings of rhodopsin diversity, function and evolution are contributing to broader microbiological and molecular knowledge. Here, we describe MicRhoDE, a comprehensive, high-quality and freely accessible database that facilitates analysis of the diversity and evolution of microbial rhodopsins. Rhodopsin sequences isolated from a vast array of marine and terrestrial environments were manually collected and curated. To each rhodopsin sequence are associated related metadata, including predicted spectral tuning of the protein, putative activity and function, taxonomy for sequences that can be linked to a 16S rRNA gene, sampling date and location, and supporting literature. The database currently covers 7857 aligned sequences from more than 450 environmental samples or organisms. Based on a robust phylogenetic analysis, we introduce an operational classification system with multiple phylogenetic levels ranging from superclusters to species-level operational taxonomic units. An integrated pipeline for online sequence alignment and phylogenetic tree construction is also provided. With a user-friendly interface and integrated online bioinformatics tools, this unique resource should be highly valuable for upcoming studies of the biogeography, diversity, distribution and evolution of microbial rhodopsins. Database URL: http://micrhode.sb-roscoff.fr. © The Author(s) 2015. Published by Oxford University Press.

  3. Physical soil architectural traits are functionally linked to carbon decomposition and bacterial diversity.

    PubMed

    Rabbi, S M F; Daniel, H; Lockwood, P V; Macdonald, C; Pereg, L; Tighe, M; Wilson, B R; Young, I M

    2016-09-12

    Aggregates play a key role in protecting soil organic carbon (SOC) from microbial decomposition. The objectives of this study were to investigate the influence of pore geometry on the organic carbon decomposition rate and bacterial diversity in both macro- (250-2000 μm) and micro-aggregates (53-250 μm) using field samples. Four sites of contrasting land use on Alfisols (i.e. native pasture, crop/pasture rotation, woodland) were investigated. 3D Pore geometry of the micro-aggregates and macro-aggregates were examined by X-ray computed tomography (μCT). The occluded particulate organic carbon (oPOC) of aggregates was measured by size and density fractionation methods. Micro-aggregates had 54% less μCT observed porosity but 64% more oPOC compared with macro-aggregates. In addition, the pore connectivity in micro-aggregates was lower than macro-aggregates. Despite both lower μCT observed porosity and pore connectivity in micro-aggregates, the organic carbon decomposition rate constant (Ksoc) was similar in both aggregate size ranges. Structural equation modelling showed a strong positive relationship of the concentration of oPOC with bacterial diversity in aggregates. We use these findings to propose a conceptual model that illustrates the dynamic links between substrate, bacterial diversity, and pore geometry that suggests a structural explanation for differences in bacterial diversity across aggregate sizes.

  4. Physical soil architectural traits are functionally linked to carbon decomposition and bacterial diversity

    PubMed Central

    Rabbi, S. M. F.; Daniel, H.; Lockwood, P. V.; Macdonald, C.; Pereg, L.; Tighe, M.; Wilson, B. R.; Young, I. M.

    2016-01-01

    Aggregates play a key role in protecting soil organic carbon (SOC) from microbial decomposition. The objectives of this study were to investigate the influence of pore geometry on the organic carbon decomposition rate and bacterial diversity in both macro- (250–2000 μm) and micro-aggregates (53–250 μm) using field samples. Four sites of contrasting land use on Alfisols (i.e. native pasture, crop/pasture rotation, woodland) were investigated. 3D Pore geometry of the micro-aggregates and macro-aggregates were examined by X-ray computed tomography (μCT). The occluded particulate organic carbon (oPOC) of aggregates was measured by size and density fractionation methods. Micro-aggregates had 54% less μCT observed porosity but 64% more oPOC compared with macro-aggregates. In addition, the pore connectivity in micro-aggregates was lower than macro-aggregates. Despite both lower μCT observed porosity and pore connectivity in micro-aggregates, the organic carbon decomposition rate constant (Ksoc) was similar in both aggregate size ranges. Structural equation modelling showed a strong positive relationship of the concentration of oPOC with bacterial diversity in aggregates. We use these findings to propose a conceptual model that illustrates the dynamic links between substrate, bacterial diversity, and pore geometry that suggests a structural explanation for differences in bacterial diversity across aggregate sizes. PMID:27615807

  5. Long-term on-farm participatory maize breeding by stratified mass selection retains molecular diversity while improving agronomic performance.

    PubMed

    Alves, Mara Lisa; Belo, Maria; Carbas, Bruna; Brites, Cláudia; Paulo, Manuel; Mendes-Moreira, Pedro; Brites, Carla; Bronze, Maria do Rosário; Šatović, Zlatko; Vaz Patto, Maria Carlota

    2018-02-01

    Modern maize breeding programs gave rise to genetically uniform varieties that can affect maize's capacity to cope with increasing climate unpredictability. Maize populations, genetically more heterogeneous, can evolve and better adapt to a broader range of edaphic-climatic conditions. These populations usually suffer from low yields; it is therefore desirable to improve their agronomic performance while maintaining their valuable diversity levels. With this objective, a long-term participatory breeding/on-farm conservation program was established in Portugal. In this program, maize populations were subject to stratified mass selection. This work aimed to estimate the effect of on-farm stratified mass selection on the agronomic performance, quality, and molecular diversity of two historical maize populations. Multilocation field trials, comparing the initial populations with the derived selection cycles, showed that this selection methodology led to agronomic improvement for one of the populations. The molecular diversity analysis, using microsatellites, revealed that overall genetic diversity in both populations was maintained throughout selection. The comparison of quality parameters between the initial populations and the derived selection cycles was made using kernel from a common-garden experiment. This analysis showed that the majority of the quality traits evaluated progressed erratically over time. In conclusion, this breeding approach, through simple and low-cost methodologies, proved to be an alternative strategy for genetic resources' on-farm conservation.

  6. Diverse effects of degree of urbanisation and forest size on species richness and functional diversity of plants, and ground surface-active ants and spiders

    PubMed Central

    Melliger, Ramona Laila; Rusterholz, Hans-Peter; Baur, Bruno

    2018-01-01

    Urbanisation is increasing worldwide and is regarded a major driver of environmental change altering local species assemblages in urban green areas. Forests are one of the most frequent habitat types in urban landscapes harbouring many native species and providing important ecosystem services. By using a multi-taxa approach covering a range of trophic ranks, we examined the influence of degree of urbanisation and forest size on the species richness and functional diversity of plants, and ground surface-active ants and spiders. We conducted field surveys in twenty-six forests in the urban region of Basel, Switzerland. We found that a species’ response to urbanisation varied depending on trophic rank, habitat specificity and the diversity indices used. In plants, species richness decreased with degree of urbanisation, whereas that of both arthropod groups was not affected. However, ants and spiders at higher trophic rank showed greater shifts in species composition with increasing degree of urbanisation, and the percentage of forest specialists in both arthropod groups increased with forest size. Local abiotic site characteristics were also crucial for plant species diversity and species composition, while the structural diversity of both leaf litter and vegetation was important for the diversity of ants and spiders. Our results highlight that even small urban forests can harbour a considerable biodiversity including habitat specialists. Nonetheless, urbanisation directly and indirectly caused major shifts in species composition. Therefore, special consideration needs to be given to vulnerable species, including those with special habitat requirements. Locally adapted management practices could be a step forward to enhance habitat quality in a way to maximize diversity of forest species and thus ensure forest ecosystem functioning; albeit large-scale factors also remain important. PMID:29920553

  7. Diverse effects of degree of urbanisation and forest size on species richness and functional diversity of plants, and ground surface-active ants and spiders.

    PubMed

    Melliger, Ramona Laila; Braschler, Brigitte; Rusterholz, Hans-Peter; Baur, Bruno

    2018-01-01

    Urbanisation is increasing worldwide and is regarded a major driver of environmental change altering local species assemblages in urban green areas. Forests are one of the most frequent habitat types in urban landscapes harbouring many native species and providing important ecosystem services. By using a multi-taxa approach covering a range of trophic ranks, we examined the influence of degree of urbanisation and forest size on the species richness and functional diversity of plants, and ground surface-active ants and spiders. We conducted field surveys in twenty-six forests in the urban region of Basel, Switzerland. We found that a species' response to urbanisation varied depending on trophic rank, habitat specificity and the diversity indices used. In plants, species richness decreased with degree of urbanisation, whereas that of both arthropod groups was not affected. However, ants and spiders at higher trophic rank showed greater shifts in species composition with increasing degree of urbanisation, and the percentage of forest specialists in both arthropod groups increased with forest size. Local abiotic site characteristics were also crucial for plant species diversity and species composition, while the structural diversity of both leaf litter and vegetation was important for the diversity of ants and spiders. Our results highlight that even small urban forests can harbour a considerable biodiversity including habitat specialists. Nonetheless, urbanisation directly and indirectly caused major shifts in species composition. Therefore, special consideration needs to be given to vulnerable species, including those with special habitat requirements. Locally adapted management practices could be a step forward to enhance habitat quality in a way to maximize diversity of forest species and thus ensure forest ecosystem functioning; albeit large-scale factors also remain important.

  8. Cryo-electron tomography of bacterial viruses

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guerrero-Ferreira, Ricardo C.; Wright, Elizabeth R., E-mail: erwrigh@emory.edu

    2013-01-05

    Bacteriophage particles contain both simple and complex macromolecular assemblages and machines that enable them to regulate the infection process under diverse environmental conditions with a broad range of bacterial hosts. Recent developments in cryo-electron tomography (cryo-ET) make it possible to observe the interactions of bacteriophages with their host cells under native-state conditions at unprecedented resolution and in three-dimensions. This review describes the application of cryo-ET to studies of bacteriophage attachment, genome ejection, assembly and egress. Current topics of investigation and future directions in the field are also discussed.

  9. The Use of Mathematical Modelling for Improving the Tissue Engineering of Organs and Stem Cell Therapy.

    PubMed

    Lemon, Greg; Sjoqvist, Sebastian; Lim, Mei Ling; Feliu, Neus; Firsova, Alexandra B; Amin, Risul; Gustafsson, Ylva; Stuewer, Annika; Gubareva, Elena; Haag, Johannes; Jungebluth, Philipp; Macchiarini, Paolo

    2016-01-01

    Regenerative medicine is a multidisciplinary field where continued progress relies on the incorporation of a diverse set of technologies from a wide range of disciplines within medicine, science and engineering. This review describes how one such technique, mathematical modelling, can be utilised to improve the tissue engineering of organs and stem cell therapy. Several case studies, taken from research carried out by our group, ACTREM, demonstrate the utility of mechanistic mathematical models to help aid the design and optimisation of protocols in regenerative medicine.

  10. Regeneration, morphogenesis and self-organization.

    PubMed

    Goldman, Daniel

    2014-07-01

    The RIKEN Center for Developmental Biology in Kobe, Japan, hosted a meeting entitled 'Regeneration of Organs: Programming and Self-Organization' in March, 2014. Scientists from across the globe met to discuss current research on regeneration, organ morphogenesis and self-organization - and the links between these fields. A diverse range of experimental models and organ systems was presented, and the speakers aptly illustrated the unique power of each. This Meeting Review describes the major advances reported and themes emerging from this exciting meeting. © 2014. Published by The Company of Biologists Ltd.

  11. Diverse Applications of Nanomedicine

    PubMed Central

    2017-01-01

    The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic. PMID:28290206

  12. CU Prime Diversity Workshops: Creating Spaces for Growth Amongst Organizers

    NASA Astrophysics Data System (ADS)

    Hyater-Adams, Simone

    2016-03-01

    CU Prime is a graduate student run organization that was created as a way to promote community and inclusion amongst students in CU Physics Department. With a mission to improve the experiences of students, especially those underrepresented in the department and field, the core organizers developed three programs: a seminar series, a class, and a mentorship program. However, because this is strictly volunteer time for most organizers, there is little time for development and growth as a group. In response, we developed a series of diversity workshops for the group, in order to provide space and time for organizers to reflect on and grapple with difficult issues around diversity and inclusion that are important to think about when running these programs. With a structure based on readings, informal videos, and reflection, there have been 5 workshops around topics ranging from gender in physics to how to be an ally. We overview the structure and framing of these workshops, along with the challenges and successes throughout the process of developing them, along with plans for future development.

  13. Focus on the emerging new fields of network physiology and network medicine

    NASA Astrophysics Data System (ADS)

    Ivanov, Plamen Ch; Liu, Kang K. L.; Bartsch, Ronny P.

    2016-10-01

    Despite the vast progress and achievements in systems biology and integrative physiology in the last decades, there is still a significant gap in understanding the mechanisms through which (i) genomic, proteomic and metabolic factors and signaling pathways impact vertical processes across cells, tissues and organs leading to the expression of different disease phenotypes and influence the functional and clinical associations between diseases, and (ii) how diverse physiological systems and organs coordinate their functions over a broad range of space and time scales and horizontally integrate to generate distinct physiologic states at the organism level. Two emerging fields, network medicine and network physiology, aim to address these fundamental questions. Novel concepts and approaches derived from recent advances in network theory, coupled dynamical systems, statistical and computational physics show promise to provide new insights into the complexity of physiological structure and function in health and disease, bridging the genetic and sub-cellular level with inter-cellular interactions and communications among integrated organ systems and sub-systems. These advances form first building blocks in the methodological formalism and theoretical framework necessary to address fundamental problems and challenges in physiology and medicine. This ‘focus on’ issue contains 26 articles representing state-of-the-art contributions covering diverse systems from the sub-cellular to the organism level where physicists have key role in laying the foundations of these new fields.

  14. Modeling of a pitching and plunging airfoil using experimental flow field and load measurements

    NASA Astrophysics Data System (ADS)

    Troshin, Victor; Seifert, Avraham

    2018-01-01

    The main goal of the current paper is to outline a low-order modeling procedure of a heaving airfoil in a still fluid using experimental measurements. Due to its relative simplicity, the proposed procedure is applicable for the analysis of flow fields within complex and unsteady geometries and it is suitable for analyzing the data obtained by experimentation. Currently, this procedure is used to model and predict the flow field evolution using a small number of low profile load sensors and flow field measurements. A time delay neural network is used to estimate the flow field. The neural network estimates the amplitudes of the most energetic modes using four sensory inputs. The modes are calculated using proper orthogonal decomposition of the flow field data obtained experimentally by time-resolved, phase-locked particle imaging velocimetry. To permit the use of proper orthogonal decomposition, the measured flow field is mapped onto a stationary domain using volume preserving transformation. The analysis performed by the model showed good estimation quality within the parameter range used in the training procedure. However, the performance deteriorates for cases out of this range. This situation indicates that, to improve the robustness of the model, both the decomposition and the training data sets must be diverse in terms of input parameter space. In addition, the results suggest that the property of volume preservation of the mapping does not affect the model quality as long as the model is not based on the Galerkin approximation. Thus, it may be relaxed for cases with more complex geometry and kinematics.

  15. Contrasting diversity patterns of soil mites and nematodes in secondary succession

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kardol, Paul; Newton, Jeffrey S.; Bezemer, T Martijn

    2009-01-01

    Soil biodiversity has been recognized as a key feature of ecosystem functioning and stability. However, soil biodiversity is strongly impaired by agriculture and relatively little is known on how and at what spatial and temporal scales soil biodiversity is restored after the human disturbances have come to an end. Here, a multi-scale approach was used to compare diversity patterns of soil mites and nematodes at four stages (early, mid, late, reference site) along a secondary succession chronosequence from abandoned arable land to heath land. In each field four soil samples were taken during four successive seasons. We determined soil diversitymore » within samples ({alpha}-diversity), between samples ({beta}-diversity) and within field sites ({gamma}-diversity). The patterns of {alpha}- and {gamma}-diversity developed similarly along the chronosequence for oribatid mites, but not for nematodes. Nematode {alpha}-diversity was highest in mid- and late-successional sites, while {gamma}-diversity was constant along the chronosequence. Oribatid mite {beta}-diversity was initially high, but decreased thereafter, whereas nematode {beta}-diversity increased when succession proceeded; indicating that patterns of within-site heterogeneity diverged for oribatid mites and nematodes. The spatio-temporal diversity patterns after land abandonment suggest that oribatid mite community development depends predominantly on colonization of new taxa, whereas nematode community development depends on shifts in dominance patterns. This would imply that at old fields diversity patterns of oribatid mites are mainly controlled by dispersal, whereas diversity patterns of nematodes are mainly controlled by changing abiotic or biotic soil conditions. Our study shows that the restoration of soil biodiversity along secondary successional gradients can be both scale- and phylum-dependent.« less

  16. Genetic diversity and population structure of Chinese natural bermudagrass [Cynodon dactylon (L.) Pers.] germplasm based on SRAP markers.

    PubMed

    Zheng, Yiqi; Xu, Shaojun; Liu, Jing; Zhao, Yan; Liu, Jianxiu

    2017-01-01

    Bermudagrass [Cynodon dactylon (L.) Pers.], an important turfgrass used in public parks, home lawns, golf courses and sports fields, is widely distributed in China. In the present study, sequence-related amplified polymorphism (SRAP) markers were used to assess genetic diversity and population structure among 157 indigenous bermudagrass genotypes from 20 provinces in China. The application of 26 SRAP primer pairs produced 340 bands, of which 328 (96.58%) were polymorphic. The polymorphic information content (PIC) ranged from 0.36 to 0.49 with a mean of 0.44. Genetic distance coefficients among accessions ranged from 0.04 to 0.61, with an average of 0.32. The results of STRUCTURE analysis suggested that 157 bermudagrass accessions can be grouped into three subpopulations. Moreover, according to clustering based on the unweighted pair-group method of arithmetic averages (UPGMA), accessions were divided into three major clusters. The UPGMA dendrogram revealed that accessions from identical or adjacent areas were generally, but not entirely, clustered into the same cluster. Comparison of the UPGMA dendrogram and the Bayesian STRUCTURE analysis showed general agreement between the population subdivisions and the genetic relationships among accessions. Principal coordinate analysis (PCoA) with SRAP markers revealed a similar grouping of accessions to the UPGMA dendrogram and STRUCTUE analysis. Analysis of molecular variance (AMOVA) indicated that 18% of total molecular variance was attributed to diversity among subpopulations, while 82% of variance was associated with differences within subpopulations. Our study represents the most comprehensive investigation of the genetic diversity and population structure of bermudagrass in China to date, and provides valuable information for the germplasm collection, genetic improvement, and systematic utilization of bermudagrass.

  17. Species composition, diversity and relative abundance of amphibians in forests and non-forest habitats on Langkawi Island, Peninsular Malaysia

    NASA Astrophysics Data System (ADS)

    Nur Johana, J.; Muzzneena, A. M.; Grismer, L. L.; Norhayati, A.

    2016-11-01

    Anurans on Langkawi Island, Peninsular Malaysia exhibit variation in their habits and forms, ranging from small (SVL < 25 mm) to large (SVL > 150 mm), and occupy a range of habitats, such as riverine forests, agricultural fields, peat swamps, and lowland and upland dipterocarp forests. These variations provide a platform to explore species diversity, distribution, abundance, microhabitat, and other ecological parameters to understand the distribution patterns and to facilitate conservation and management of sensitive or important species and areas. The objective of this study was to evaluate the diversity and distribution of anuran species in different types of habitat on Langkawi Island. Specimens were collected based on active sampling using the Visual Encounter Survey (VES) method. We surveyed anuran species inhabiting seven types of habitat, namely agriculture (AG), coastal (CL), forest (FT), pond (PD), mangrove (MG), riparian forest (RF) and river (RV). A total of 775 individuals were sampled from all localities, representing 23 species from 12 genera and included all six families of frogs in Malaysia. FT and RF showed high values of Shannon Index, H', 2.60 and 2.38, respectively, followed by the other types of habitat, CL (1.82), RV (1.71), MG (1.56), PD (1.54), and AG (1.53). AG had the highest abundance (156 individuals) compared to other habitat types. Based on Cluster Analysis by using Jaccard coefficient (UPGMA), two groups can be clearly seen and assigned as forested species group (FT and RF) and species associating with human activity (AG, CL, PD, MG and RV). Forest species group is more diverse compared to non-forest group. Nevertheless, non-forest species are found in abundance, highlighting the relevance of these disturbed habitats in supporting the amphibians.

  18. Genetic diversity and population structure of Chinese natural bermudagrass [Cynodon dactylon (L.) Pers.] germplasm based on SRAP markers

    PubMed Central

    Xu, Shaojun; Liu, Jing; Zhao, Yan; Liu, Jianxiu

    2017-01-01

    Bermudagrass [Cynodon dactylon (L.) Pers.], an important turfgrass used in public parks, home lawns, golf courses and sports fields, is widely distributed in China. In the present study, sequence-related amplified polymorphism (SRAP) markers were used to assess genetic diversity and population structure among 157 indigenous bermudagrass genotypes from 20 provinces in China. The application of 26 SRAP primer pairs produced 340 bands, of which 328 (96.58%) were polymorphic. The polymorphic information content (PIC) ranged from 0.36 to 0.49 with a mean of 0.44. Genetic distance coefficients among accessions ranged from 0.04 to 0.61, with an average of 0.32. The results of STRUCTURE analysis suggested that 157 bermudagrass accessions can be grouped into three subpopulations. Moreover, according to clustering based on the unweighted pair-group method of arithmetic averages (UPGMA), accessions were divided into three major clusters. The UPGMA dendrogram revealed that accessions from identical or adjacent areas were generally, but not entirely, clustered into the same cluster. Comparison of the UPGMA dendrogram and the Bayesian STRUCTURE analysis showed general agreement between the population subdivisions and the genetic relationships among accessions. Principal coordinate analysis (PCoA) with SRAP markers revealed a similar grouping of accessions to the UPGMA dendrogram and STRUCTUE analysis. Analysis of molecular variance (AMOVA) indicated that 18% of total molecular variance was attributed to diversity among subpopulations, while 82% of variance was associated with differences within subpopulations. Our study represents the most comprehensive investigation of the genetic diversity and population structure of bermudagrass in China to date, and provides valuable information for the germplasm collection, genetic improvement, and systematic utilization of bermudagrass. PMID:28493962

  19. Discovery of a novel mastrevirus and alphasatellite-like circular DNA in dragonflies (Epiprocta) from Puerto Rico.

    PubMed

    Rosario, Karyna; Padilla-Rodriguez, Marco; Kraberger, Simona; Stainton, Daisy; Martin, Darren P; Breitbart, Mya; Varsani, Arvind

    2013-01-01

    Geminiviruses have emerged as serious agricultural pathogens. Despite all the species that have been already catalogued, new molecular techniques continue to expand the diversity and geographical ranges of these single-stranded DNA viruses and their associated satellite molecules. Since all geminiviruses are insect-transmitted, examination of insect vector populations through vector-enabled metagenomics (VEM) has been recently used to investigate the diversity of geminiviruses transmitted by a specific vector in a given region. Here we used a more comprehensive adaptation of the VEM approach by surveying small circular DNA viruses found within top insect predators, specifically dragonflies (Epiprocta). This 'predator-enabled' approach is not limited to viral groups transmitted by specific vectors since dragonflies can accumulate the wide range of viruses transmitted by their diverse insect prey. Analysis of six dragonflies collected from an agricultural field in Puerto Rico culminated in the discovery of the first mastrevirus (Dragonfly-associated mastrevirus; DfasMV) and alphasatellite molecule (Dragonfly-associated alphasatellite; Dfas-alphasatellite) from the Caribbean. Since DfasMV and Dfas-alphasatellite are divergent from the limited number of sequences that have been reported from the Americas, this study unequivocally demonstrates that there have been at least two independent past introductions of both mastreviruses and alphasatellites to the New World. Overall, the use of predacious insects as sampling tools can profoundly alter our views of natural plant virus diversity and biogeography by allowing the discovery of novel geminiviruses and associated satellite molecules without a priori knowledge of the types of viruses or insect vectors in a given area. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Beginning Teachers and Inclusive Education: Frustrations, Dilemmas and Growth

    ERIC Educational Resources Information Center

    McKay, Loraine

    2016-01-01

    Scholars report desirable outcomes for all participants in classrooms where diverse learners are welcomed members. Data suggest teachers leave the profession early because of the demands of their work made increasingly difficult by the diverse range of students, lack of assistance to support the diverse range of student needs and the resulting…

  1. Mapping Plant Diversity and Composition Across North Carolina Piedmont Forest Landscapes Using Lidar-Hyperspectral Remote Sensing

    NASA Astrophysics Data System (ADS)

    Hakkenberg, Christopher R.

    Forest modification, from local stress to global change, has given rise to efforts to model, map, and monitor critical properties of forest communities like structure, composition, and diversity. Predictive models based on data from spatially-nested field plots and LiDAR-hyperspectral remote sensing systems are one particularly effective means towards the otherwise prohibitively resource-intensive task of consistently characterizing forest community dynamics at landscape scales. However, to date, most predictive models fail to account for actual (rather than idealized) species and community distributions, are unsuccessful in predicting understory components in structurally and taxonomically heterogeneous forests, and may suffer from diminished predictive accuracy due to incongruity in scale and precision between field plot samples, remotely-sensed data, and target biota of varying size and density. This three-part study addresses these and other concerns in the modeling and mapping of emergent properties of forest communities by shifting the scope of prediction from the individual or taxon to the whole stand or community. It is, after all, at the stand scale where emergent properties like functional processes, biodiversity, and habitat aggregate and manifest. In the first study, I explore the relationship between forest structure (a proxy for successional demographics and resource competition) and tree species diversity in the North Carolina Piedmont, highlighting the empirical basis and potential for utilizing forest structure from LiDAR in predictive models of tree species diversity. I then extend these conclusions to map landscape pattern in multi-scale vascular plant diversity as well as turnover in community-continua at varying compositional resolutions in a North Carolina Piedmont landscape using remotely-sensed LiDAR-hyperspectral estimates of topography, canopy structure, and foliar biochemistry. Recognizing that the distinction between correlation and causation mirrors that between knowledge and understanding, all three studies distinguish between prediction of pattern and inference of process. Thus, in addition to advancing mapping methodologies relevant to a range of forest ecosystem management and monitoring applications, all three studies are noteworthy for assessing the ecological relationship between environmental predictors and emergent landscape patterns in plant composition and diversity in North Carolina Piedmont forests.

  2. Identifying Centres of Plant Biodiversity in South Australia

    PubMed Central

    Guerin, Greg R.; Biffin, Ed; Baruch, Zdravko; Lowe, Andrew J.

    2016-01-01

    We aimed to identify regional centres of plant biodiversity in South Australia, a sub-continental land area of 983,482 km2, by mapping a suite of metrics. Broad-brush conservation issues associated with the centres were mapped, specifically climate sensitivity, exposure to habitat fragmentation, introduced species and altered fire regimes. We compiled 727,417 plant species records from plot-based field surveys and herbarium records and mapped the following: species richness (all species; South Australian endemics; conservation-dependent species; introduced species); georeferenced weighted endemism, phylogenetic diversity, georeferenced phylogenetic endemism; and measures of beta diversity at local and state-wide scales. Associated conservation issues mapped were: climate sensitivity measured via ordination and non-linear modelling; habitat fragmentation represented by the proportion of remnant vegetation within a moving window; fire prone landscapes assessed using fire history records; invasive species assessed through diversity metrics, species distribution and literature. Compared to plots, herbarium data had higher spatial and taxonomic coverage but records were more biased towards major transport corridors. Beta diversity was influenced by sampling intensity and scale of comparison. We identified six centres of high plant biodiversity for South Australia: Western Kangaroo Island; Southern Mount Lofty Ranges; Anangu Pitjantjatjara Yankunytjatjara lands; Southern Flinders Ranges; Southern Eyre Peninsula; Lower South East. Species composition in the arid-mediterranean ecotone was the most climate sensitive. Fragmentation mapping highlighted the dichotomy between extensive land-use and high remnancy in the north and intensive land-use and low remnancy in the south. Invasive species were most species rich in agricultural areas close to population centres. Fire mapping revealed large variation in frequency across the state. Biodiversity scores were not always congruent between metrics or datasets, notably for categorical endemism to South Australia versus georeferenced weighted endemism, justifying diverse approaches and cautious interpretation. The study could be extended to high resolution assessments of biodiversity centres and cost:benefit analysis for interventions. PMID:26735131

  3. Frontiers of two-dimensional correlation spectroscopy. Part 2. Perturbation methods, fields of applications, and types of analytical probes

    NASA Astrophysics Data System (ADS)

    Noda, Isao

    2014-07-01

    Noteworthy experimental practices, which are advancing forward the frontiers of the field of two-dimensional (2D) correlation spectroscopy, are reviewed with the focus on various perturbation methods currently practiced to induce spectral changes, pertinent examples of applications in various fields, and types of analytical probes employed. Types of perturbation methods found in the published literature are very diverse, encompassing both dynamic and static effects. Although a sizable portion of publications report the use of dynamic perturbatuions, much greater number of studies employ static effect, especially that of temperature. Fields of applications covered by the literature are also very broad, ranging from fundamental research to practical applications in a number of physical, chemical and biological systems, such as synthetic polymers, composites and biomolecules. Aside from IR spectroscopy, which is the most commonly used tool, many other analytical probes are used in 2D correlation analysis. The ever expanding trend in depth, breadth and versatility of 2D correlation spectroscopy techniques and their broad applications all point to the robust and healthy state of the field.

  4. Decline of traditional rice farming constrains the recovery of the endangered Asian crested ibis (Nipponia nippon).

    PubMed

    Sun, Yiwen; Wang, Tiejun; Skidmore, Andrew K; Wang, Qi; Ding, Changqing

    2015-12-01

    Traditional agriculture benefits a rich diversity of plants and animals. The winter-flooded rice fields in the Qinling Mountains, China, are the last refuge for the endangered Asian crested ibis (Nipponia nippon), and intensive efforts have been made to protect this anthropogenic habitat. Analyses of multi-temporal satellite data indicate that winter-flooded rice fields have been continuously reduced across the current range of crested ibis during the past two decades. The rate of loss of these fields in the core-protected areas has unexpectedly increased to a higher level than that in non-protected areas in the past decade. The best fit (R (2) = 0.87) numerical response model of the crested ibis population shows that a reduction of winter-flooded rice fields decreases population growth and predicts that the population growth will be constrained by the decline of traditional winter-flooded rice fields in the coming decades. Our findings suggest that the decline of traditional rice farming is likely to continue to pose a threat to the long-term survival and recovery of the crested ibis population in China.

  5. Evolutionary history of a vanishing radiation: isolation-dependent persistence and diversification in Pacific Island partulid tree snails.

    PubMed

    Lee, Taehwan; Li, Jingchun; Churchill, Celia K C; Foighil, Diarmaid Ó

    2014-09-24

    Partulid tree snails are endemic to Pacific high islands and have experienced extraordinary rates of extinction in recent decades. Although they collectively range across a 10,000 km swath of Oceania, half of the family's total species diversity is endemic to a single Eastern Pacific hot spot archipelago (the Society Islands) and all three partulid genera display highly distinctive distributions. Our goal was to investigate broad scale (range wide) and fine scale (within-Society Islands) molecular phylogenetic relationships of the two widespread genera, Partula and Samoana. What can such data tell us regarding the genesis of such divergent generic distribution patterns, and nominal species diversity levels across Oceania? Museum, captive (zoo) and contemporary field specimens enabled us to genotype 54 of the ~120 recognized species, including many extinct or extirpated taxa, from 14 archipelagoes. The genera Partula and Samoana are products of very distinct diversification processes. Originating at the western edge of the familial range, the derived genus Samoana is a relatively recent arrival in the far eastern archipelagoes (Society, Austral, Marquesas) where it exhibits a stepping-stone phylogenetic pattern and has proven adept at both intra-and inter- archipelago colonization. The pronounced east-west geographic disjunction exhibited by the genus Partula stems from a much older long-distance dispersal event and its high taxonomic diversity in the Society Islands is a product of a long history of within-archipelago diversification. The central importance of isolation for partulid lineage persistence and diversification is evident in time-calibrated phylogenetic trees that show that remote archipelagoes least impacted by continental biotas bear the oldest clades and/or the most speciose radiations. In contemporary Oceania, that isolation is being progressively undermined and these tree snails are now directly exposed to introduced continental predators throughout the family's range. Persistence of partulids in the wild will require proactive exclusion of alien predators in at least some designated refuge islands.

  6. Genetic diversity in the 3'-terminal region of papaya ringspot virus (PRSV-W) isolates from watermelon in Oklahoma.

    PubMed

    Abdalla, Osama A; Ali, Akhtar

    2012-03-01

    The 3'-terminal region (1191 nt) containing part of the NIb gene, complete coat protein (CP) and poly-A tail of 64 papaya ringspot virus (PRSV-W) isolates collected during 2008-2009 from watermelon in commercial fields of four different counties of Oklahoma were cloned and sequenced. Nucleotide and amino acid sequence identities ranged from 95.2-100% and 97.1-100%, respectively, among the Oklahoman PRSV-W isolates. Phylogenetic analysis showed that PRSW-W isolates clustered according to the locations where they were collected within Oklahoma, and each cluster contained two subgroups. All subgroups of Oklahoman PRSV-W isolates were on separate branches when compared to 35 known isolates originating from other parts of the world, including the one reported previously from the USA. This study helps in our understanding about the genetic diversity of PRSV-W isolates infecting cucurbits in Oklahoma.

  7. Design of virus-based nanomaterials for medicine, biotechnology, and energy.

    PubMed

    Wen, Amy M; Steinmetz, Nicole F

    2016-07-25

    This review provides an overview of recent developments in "chemical virology." Viruses, as materials, provide unique nanoscale scaffolds that have relevance in chemical biology and nanotechnology, with diverse areas of applications. Some fundamental advantages of viruses, compared to synthetically programmed materials, include the highly precise spatial arrangement of their subunits into a diverse array of shapes and sizes and many available avenues for easy and reproducible modification. Here, we will first survey the broad distribution of viruses and various methods for producing virus-based nanoparticles, as well as engineering principles used to impart new functionalities. We will then examine the broad range of applications and implications of virus-based materials, focusing on the medical, biotechnology, and energy sectors. We anticipate that this field will continue to evolve and grow, with exciting new possibilities stemming from advancements in the rational design of virus-based nanomaterials.

  8. A contribution to the study of the Lower Volga center of scarab beetle diversity in Russia: checklist of the tribe Aphodiini (Coleoptera, Scarabaeidae) of Dosang environs

    PubMed Central

    2013-01-01

    Abstract The field sampling of the Aphodiini scarab beetles in Dosang environs (Astrakhan Province, European Russia) in 2006–2012 resulted in the collection of 44 species. All but one of them belong to Aphodius Hellwig (sensu lato). This is apparently the richest recorded local Aphodiini fauna in Russia. The high Aphodiini diversity in the area can be explained by the long vegetative season with high effective heat sum, large livestock providing abundant food resources throughout the year, and location in the transition belt between Volga-Akhtuba Floodplain and Desert floristic districts. The core fauna consists of mesophilous species widely distributed in the Palearctic region and confined to the intrazonal habitats. Other species have ranges mostly limited to the steppe, semidesert, and desert zones. PMID:24723773

  9. Microbial diversity of culturable heterotrophs in the rhizosphere of salt marsh grass, Porteresia coarctata (Tateoka) in a mangrove ecosystem.

    PubMed

    Bharathkumar, Srinivasan; Paul, Diby; Nair, Sudha

    2008-02-01

    A study was conducted to understand the complexity of bacterial diversity of rhizosphere of Porteresia coarctata based on culture dependent method. A large number of bacteria were isolated on nutrient agar medium supplemented with 1% NaCl and the dominant ones were further analyzed with PCR-RFLP method. The sequence analyses of the dominant strains revealed that most of the sequences belonged to members of gamma proteobacteria, firmicutes, bacteroidetes and uncultured bacteria. The phylogenetic analysis of 16S rRNA gene sequences revealed close relationships to a wide range of clones or bacterial species of various divisions. These results afford an understanding of the role of rhizobacteria in alleviating salt stress in Porteresia coarctata expected to contribute towards long-term goal of improving plant-microbe interactions for salinity affected fields. (c) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Functional gene array-based analysis of microbial community structure in groundwaters with a gradient of contaminant levels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Waldron, P.J.; Wu, L.; Van Nostrand, J.D.

    2009-06-15

    To understand how contaminants affect microbial community diversity, heterogeneity, and functional structure, six groundwater monitoring wells from the Field Research Center of the U.S. Department of Energy Environmental Remediation Science Program (ERSP; Oak Ridge, TN), with a wide range of pH, nitrate, and heavy metal contamination were investigated. DNA from the groundwater community was analyzed with a functional gene array containing 2006 probes to detect genes involved in metal resistance, sulfate reduction, organic contaminant degradation, and carbon and nitrogen cycling. Microbial diversity decreased in relation to the contamination levels of the wells. Highly contaminated wells had lower gene diversity butmore » greater signal intensity than the pristine well. The microbial composition was heterogeneous, with 17-70% overlap between different wells. Metal-resistant and metal-reducing microorganisms were detected in both contaminated and pristine wells, suggesting the potential for successful bioremediation of metal-contaminated groundwaters. In addition, results of Mantel tests and canonical correspondence analysis indicate that nitrate, sulfate, pH, uranium, and technetium have a significant (p < 0.05) effect on microbial community structure. This study provides an overall picture of microbial community structure in contaminated environments with functional gene arrays by showing that diversity and heterogeneity can vary greatly in relation to contamination.« less

  11. Intraspecies Genomic Diversity and Natural Population Structure of the Meat-Borne Lactic Acid Bacterium Lactobacillus sakei▿ †

    PubMed Central

    Chaillou, Stéphane; Daty, Marie; Baraige, Fabienne; Dudez, Anne-Marie; Anglade, Patricia; Jones, Rhys; Alpert, Carl-Alfred; Champomier-Vergès, Marie-Christine; Zagorec, Monique

    2009-01-01

    Lactobacillus sakei is a food-borne bacterium naturally found in meat and fish products. A study was performed to examine the intraspecies diversity among 73 isolates sourced from laboratory collections in several different countries. Pulsed-field gel electrophoresis analysis demonstrated a 25% variation in genome size between isolates, ranging from 1,815 kb to 2,310 kb. The relatedness between isolates was then determined using a PCR-based method that detects the possession of 60 chromosomal genes belonging to the flexible gene pool. Ten different strain clusters were identified that had noticeable differences in their average genome size reflecting the natural population structure. The results show that many different genotypes may be isolated from similar types of meat products, suggesting a complex ecological habitat in which intraspecies diversity may be required for successful adaptation. Finally, proteomic analysis revealed a slight difference between the migration patterns of highly abundant GapA isoforms of the two prevailing L. sakei subspecies (sakei and carnosus). This analysis was used to affiliate the genotypic clusters with the corresponding subspecies. These findings reveal for the first time the extent of intraspecies genomic diversity in L. sakei. Consequently, identification of molecular subtypes may in the future prove valuable for a better understanding of microbial ecosystems in food products. PMID:19114527

  12. Site-specific recombination in the chicken genome using Flipase recombinase-mediated cassette exchange.

    PubMed

    Lee, Hong Jo; Lee, Hyung Chul; Kim, Young Min; Hwang, Young Sun; Park, Young Hyun; Park, Tae Sub; Han, Jae Yong

    2016-02-01

    Targeted genome recombination has been applied in diverse research fields and has a wide range of possible applications. In particular, the discovery of specific loci in the genome that support robust and ubiquitous expression of integrated genes and the development of genome-editing technology have facilitated rapid advances in various scientific areas. In this study, we produced transgenic (TG) chickens that can induce recombinase-mediated gene cassette exchange (RMCE), one of the site-specific recombination technologies, and confirmed RMCE in TG chicken-derived cells. As a result, we established TG chicken lines that have, Flipase (Flp) recognition target (FRT) pairs in the chicken genome, mediated by piggyBac transposition. The transgene integration patterns were diverse in each TG chicken line, and the integration diversity resulted in diverse levels of expression of exogenous genes in each tissue of the TG chickens. In addition, the replaced gene cassette was expressed successfully and maintained by RMCE in the FRT predominant loci of TG chicken-derived cells. These results indicate that targeted genome recombination technology with RMCE could be adaptable to TG chicken models and that the technology would be applicable to specific gene regulation by cis-element insertion and customized expression of functional proteins at predicted levels without epigenetic influence. © FASEB.

  13. Intraspecies genomic diversity and natural population structure of the meat-borne lactic acid bacterium Lactobacillus sakei.

    PubMed

    Chaillou, Stéphane; Daty, Marie; Baraige, Fabienne; Dudez, Anne-Marie; Anglade, Patricia; Jones, Rhys; Alpert, Carl-Alfred; Champomier-Vergès, Marie-Christine; Zagorec, Monique

    2009-02-01

    Lactobacillus sakei is a food-borne bacterium naturally found in meat and fish products. A study was performed to examine the intraspecies diversity among 73 isolates sourced from laboratory collections in several different countries. Pulsed-field gel electrophoresis analysis demonstrated a 25% variation in genome size between isolates, ranging from 1,815 kb to 2,310 kb. The relatedness between isolates was then determined using a PCR-based method that detects the possession of 60 chromosomal genes belonging to the flexible gene pool. Ten different strain clusters were identified that had noticeable differences in their average genome size reflecting the natural population structure. The results show that many different genotypes may be isolated from similar types of meat products, suggesting a complex ecological habitat in which intraspecies diversity may be required for successful adaptation. Finally, proteomic analysis revealed a slight difference between the migration patterns of highly abundant GapA isoforms of the two prevailing L. sakei subspecies (sakei and carnosus). This analysis was used to affiliate the genotypic clusters with the corresponding subspecies. These findings reveal for the first time the extent of intraspecies genomic diversity in L. sakei. Consequently, identification of molecular subtypes may in the future prove valuable for a better understanding of microbial ecosystems in food products.

  14. The diverse utility of ground-based magnetometer data

    NASA Astrophysics Data System (ADS)

    Love, J. J.

    2012-12-01

    The global network of magnetic observatories represents a unique collective asset for the scientific community. Since observatory data record a wide range of physical phenomena, they are also used for a wide range of applications. Historically, magnetic observatories were first established in the 19th century to support global magnetic-field mapping projects, and this application continues to be important today. But since the dawn of the space age and the International Geophysical Year, observatory data have become important for research analysis of the ionosphere, the magnetosphere, and, indirectly, the heliosphere. Over the past couple of solar cycles, magnetic observatories have also played an important role in real-time operational monitoring of the changing conditions of space weather and assessment of ground-level geomagnetic hazards. This diversification and expansion of the observatory-data user community has brought demands for data that meet new and more stringent standards. In cooperation with the many institutes that support magnetic observatories, INTERMAGNET has been helping to coordinate and facilitate observatory modernization and improved operation. In this presentation, we give an overview of the diversity of signals recorded in observatory data, including secular, quiet, storm-time, and solar-cycle variations. We discuss future opportunities, especially for global integration and data sharing.

  15. Emergent Rotational Symmetries in Disordered Magnetic Domain Patterns

    NASA Astrophysics Data System (ADS)

    Su, Run; Seu, Keoki A.; Parks, Daniel; Kan, Jimmy J.; Fullerton, Eric E.; Roy, Sujoy; Kevan, Stephen D.

    2011-12-01

    Uniaxial systems often form labyrinthine domains that exhibit short-range order but are macroscopically isotropic and would not be expected to exhibit precise symmetries. However, their underlying frustration results in a multitude of metastable configurations of comparable energy, and driving such a system externally might lead to pattern formation. We find that soft x-ray speckle diffraction patterns of the labyrinthine domains in CoPd/IrMn heterostructures reveal a diverse array of hidden rotational symmetries about the magnetization axis, thereby suggesting an unusual form of emergent order in an otherwise disordered system. These symmetries depend on applied magnetic field, magnetization history, and scattering wave vector. Maps of rotational symmetry exhibit intriguing structures that can be controlled by manipulating the applied magnetic field in concert with the exchange bias condition.

  16. Emergent rotational symmetries in disordered magnetic domain patterns.

    PubMed

    Su, Run; Seu, Keoki A; Parks, Daniel; Kan, Jimmy J; Fullerton, Eric E; Roy, Sujoy; Kevan, Stephen D

    2011-12-16

    Uniaxial systems often form labyrinthine domains that exhibit short-range order but are macroscopically isotropic and would not be expected to exhibit precise symmetries. However, their underlying frustration results in a multitude of metastable configurations of comparable energy, and driving such a system externally might lead to pattern formation. We find that soft x-ray speckle diffraction patterns of the labyrinthine domains in CoPd/IrMn heterostructures reveal a diverse array of hidden rotational symmetries about the magnetization axis, thereby suggesting an unusual form of emergent order in an otherwise disordered system. These symmetries depend on applied magnetic field, magnetization history, and scattering wave vector. Maps of rotational symmetry exhibit intriguing structures that can be controlled by manipulating the applied magnetic field in concert with the exchange bias condition. © 2011 American Physical Society

  17. Molecular epidemiology and evolution of fish Novirhabdoviruses

    USGS Publications Warehouse

    Kurath, Gael

    2014-01-01

    The genus Novirhabdoviridae contains several of the important rhabdoviruses that infect fish hosts. There are four established virus species: Infectious hematopoietic necrosis virus (IHNV), Viral hemorrhagic septicemia virus (VHSV), Hirame rhabdovirus(HIRRV), and Snakehead rhabdovirus (SHRV). Viruses of these species vary in host and geographic range, and they have all been studied at the molecular and genomic level. As globally significant pathogens of cultured fish, IHNV and VHSV have been particularly well studied in terms of molecular epidemiology and evolution. Phylogenic analyses of hundreds of field isolates have defined five major genogroups of IHNV and four major genotypes of VHSV worldwide. These phylogenies are informed by the known histories of IHNV and VHSV, each involving a series of viral emergence events that are sometimes associated with host switches, most often into cultured rainbow trout. In general, IHNV has relatively low genetic diversity and a narrow host range, and has been spread from its endemic source in North American to Europe and Asia due to aquaculture activities. In contrast, VHSV has broad host range and high genetic diversity, and the source of emergence events is virus in widespread marine fish reservoirs in the northern Atlantic and Pacific Oceans. Common mechanisms of emergence and host switch events include use of raw feed, proximity to wild fish reservoirs of virus, and geographic translocations of virus or naive fish hosts associated with aquaculture.

  18. The emperor's new wardrobe: Rebalancing diversity of animal models in neuroscience research.

    PubMed

    Yartsev, Michael M

    2017-10-27

    The neuroscience field is steaming ahead, fueled by a revolution in cutting-edge technologies. Concurrently, another revolution has been underway-the diversity of species utilized for neuroscience research is sharply declining, as the field converges on a few selected model organisms. Here, from the perspective of a young scientist, I naively ask: Is the great diversity of questions in neuroscience best studied in only a handful of animal models? I review some of the limitations the field is facing following this convergence and how these can be rectified by increasing the diversity of appropriate model species. I propose that at this exciting time of revolution in genetics and device technologies, neuroscience might be ready to diversify again, if provided the appropriate support. Copyright © 2017, American Association for the Advancement of Science.

  19. Dartmouth College Earth Sciences Mobile Field Program

    NASA Astrophysics Data System (ADS)

    Meyer, E. E.; Osterberg, E. C.; Dade, W. B.; Sonder, L. J.; Renshaw, C. E.; Kelly, M. A.; Hawley, R. L.; Chipman, J. W.; Mikucki, J.; Posmentier, E. S.; Moore, J. R.

    2011-12-01

    For the last 50 years the Department of Earth Sciences at Dartmouth College has offered a term-long, undergraduate field program, informally called "the Stretch". A student typically enrolls during fall quarter of his or her junior year soon after choosing a major or minor. The program thus provides valuable field context for courses that a student will take during the remainder of his or her undergraduate career. Unlike many traditional field camps that focus on one particular region, the Stretch is a mobile program that currently travels through Western North America, from the Canadian Rockies to the Grand Canyon. The program spans two and a half months, during which time undergraduates, graduate TAs, and faculty live, work, and learn collaboratively. Dartmouth College faculty members sequentially teach individual 1- to 2-week segments that focus on their interests and expertise; currently, there are a total of eight segments led by eleven faculty members. Consequently, topics are diverse and include economic geology, geobiology, geomorphology, glaciology, glacial geology, geophysics, hydrogeology, paleontology, stratigraphy, structure and tectonics, and volcanology. The field localities are equally varied, including the alpine glaciers of western Alberta, the national parks of Montana, Wyoming and Utah, the eastern Sierra Nevada, the southern Great Basin, and highlight such classic geological field locales as Sheep Mountain in Wyoming's Bighorn Basin, Death Valley, and the Grand Canyon. Overall, the program aims to: 1) give students a broad perspective on the timing and nature of the processes that resulted in the landscape and underlying geology of western North America; and 2) introduce students to a wide variety of geological environments, field techniques, and research equipment. Students emerge from the program with wide-ranging exposure to active research questions as well as a working knowledge of core field skills in the earth sciences. Stretch students spend several weeks conducting traditional multiday mapping of complexly-deformed sedimentary, metamorphic and igneous rocks, and also collect and interpret geobiological, geochemical, geophysical, paleoclimatological, paleontological, and remote-sensing data outside the context of traditional mapping. During the Mono Lake segment, for example, students examine the interaction of ecology and chemistry in alkaline lakes. During the Canadian Rockies segment, students reconstruct Holocene paleoclimate using tree stumps and fossil wood detritus marking former positions of an alpine glacier. While a mobile, wide-ranging field program requires complicated logistics and potentially high per-student costs, the diversity of research topics, geological environments, and field techniques have made it a successful cornerstone of the Dartmouth Earth Sciences major. After the Stretch experience, significant fractions of our students become involved in ongoing faculty research, pursue senior theses, and go on to pursue Earth Sciences graduate degrees.

  20. Rice to vegetables: short- versus long-term impact of land-use change on the indigenous soil microbial community.

    PubMed

    Sun, Bo; Dong, Zhi-Xing; Zhang, Xue-Xian; Li, Yun; Cao, Hui; Cui, Zong-Li

    2011-08-01

    Land-use change is known to have a significant effect on the indigenous soil microbial community, but it is unknown if there are any general trends regarding how this effect varies over time. Here, we describe a comparative analysis of microbial communities from three adjacent agricultural fields: one-century-old paddy field (OP) and two vegetable fields (new vegetable field (NV) and old vegetable field (OV)) that were established on traditional paddy fields 10 and 100 years ago, respectively. Soil chemical and physical analysis showed that both vegetable fields were more nutrient rich than the paddy field in terms of organic C, total N, total P, and available K. The vegetable fields possessed relatively higher abundance of culturable bacteria, fungi, and specific groups of bacteria (Actinomyces, nitrifying bacteria, and cellulose-decomposing bacteria) but lower levels of microbial biomass C and N. Notably, the decrease of biomass was further confirmed by analysis of seven additional soils in chronosequence sampled from the same area. Next we examined the metabolic diversity of the microbial community using the EcoPlate(TM) system from Biolog Inc. (Hayward, CA, USA). The utilization patterns of 31 unique C substrates (i.e., community-level physiological profile) showed that microorganisms in vegetable soil and paddy soil prefer to use different C substrates (polymeric compounds for NV and OV soils, phenolic acids for OP soil). Principal component analysis and the average well color development data showed that the NV is metabolically more distinct from the OV and OP. The effect was likely attributable to the elevated soil pH in NV soil. Furthermore, we assessed the diversity of soil bacterial populations using the cultivation-independent technology of amplified ribosomal DNA restriction analysis (ARDRA). Results showed that levels of bacterial diversity in OP and NV soils were similar (Shannon's diversity index H = 4.83 and 4.79, respectively), whereas bacteria in OV soil have the lowest score of diversity (H = 3.48). The low level of bacterial diversity in OV soil was supported by sequencing of ten randomly selected 16S rDNA clones from each of the three rDNA libraries. Phylogenetic analysis showed that all the ten OV clones belonged to Proteobacteria with eight in the gamma-subdivision and two in the alpha-subdivision. In contrast, the ten clones from NV and OP soils were classified into four and eight bacterial classes or unclassified groups, respectively. Taken together, our data suggest that land-use change from rice to vegetables resulted in a decrease of bacterial diversity and soil biomass despite an increase in the abundance of culturable microorganisms and, moreover, the decrease of bacterial diversity occurred during long-term rather than short-term vegetable cultivation.

  1. A map of local adaptation in Arabidopsis thaliana.

    PubMed

    Fournier-Level, A; Korte, A; Cooper, M D; Nordborg, M; Schmitt, J; Wilczek, A M

    2011-10-07

    Local adaptation is critical for species persistence in the face of rapid environmental change, but its genetic basis is not well understood. Growing the model plant Arabidopsis thaliana in field experiments in four sites across the species' native range, we identified candidate loci for local adaptation from a genome-wide association study of lifetime fitness in geographically diverse accessions. Fitness-associated loci exhibited both geographic and climatic signatures of local adaptation. Relative to genomic controls, high-fitness alleles were generally distributed closer to the site where they increased fitness, occupying specific and distinct climate spaces. Independent loci with different molecular functions contributed most strongly to fitness variation in each site. Independent local adaptation by distinct genetic mechanisms may facilitate a flexible evolutionary response to changing environment across a species range.

  2. A real-time optical tracking and measurement processing system for flying targets.

    PubMed

    Guo, Pengyu; Ding, Shaowen; Zhang, Hongliang; Zhang, Xiaohu

    2014-01-01

    Optical tracking and measurement for flying targets is unlike the close range photography under a controllable observation environment, which brings extreme conditions like diverse target changes as a result of high maneuver ability and long cruising range. This paper first designed and realized a distributed image interpretation and measurement processing system to achieve resource centralized management, multisite simultaneous interpretation and adaptive estimation algorithm selection; then proposed a real-time interpretation method which contains automatic foreground detection, online target tracking, multiple features location, and human guidance. An experiment is carried out at performance and efficiency evaluation of the method by semisynthetic video. The system can be used in the field of aerospace tests like target analysis including dynamic parameter, transient states, and optical physics characteristics, with security control.

  3. A Real-Time Optical Tracking and Measurement Processing System for Flying Targets

    PubMed Central

    Guo, Pengyu; Ding, Shaowen; Zhang, Hongliang; Zhang, Xiaohu

    2014-01-01

    Optical tracking and measurement for flying targets is unlike the close range photography under a controllable observation environment, which brings extreme conditions like diverse target changes as a result of high maneuver ability and long cruising range. This paper first designed and realized a distributed image interpretation and measurement processing system to achieve resource centralized management, multisite simultaneous interpretation and adaptive estimation algorithm selection; then proposed a real-time interpretation method which contains automatic foreground detection, online target tracking, multiple features location, and human guidance. An experiment is carried out at performance and efficiency evaluation of the method by semisynthetic video. The system can be used in the field of aerospace tests like target analysis including dynamic parameter, transient states, and optical physics characteristics, with security control. PMID:24987748

  4. Armillaria species: Primary drivers of forest ecosystem processes and potential impacts of climate change

    Treesearch

    Ned B. Klopfenstein; Mee-Sook Kim; John W. Hanna; Amy L. Ross-Davis; Sara M. Ashiglar; Geral I. McDonald

    2012-01-01

    Species of the fungal genus Armillaria are pervasive in forest soils and are associated with widely ranging tree species of diverse forests worldwide (Baumgartner et al., 2011). As primary decay drivers of ecosystem processes, Armillaria species exhibit diverse ecological behaviors, ranging from virulent root and/or butt pathogens of diverse woody hosts, such as timber...

  5. Evolution of magnetic fields in collapsing star-forming clouds under different environments

    NASA Astrophysics Data System (ADS)

    Higuchi, Koki; Machida, Masahiro N.; Susa, Hajime

    2018-04-01

    In nearby star-forming clouds, amplification and dissipation of the magnetic field are known to play crucial roles in the star-formation process. The star-forming environment varies from place to place and era to era in galaxies. In this study, amplification and dissipation of magnetic fields in star-forming clouds are investigated under different environments using magnetohydrodynamics (MHD) simulations. We consider various star-forming environments in combination with the metallicity and the ionization strength, and prepare prestellar clouds having two different mass-to-flux ratios. We calculate the cloud collapse until protostar formation using ideal and non-ideal (inclusion and exclusion of ohmic dissipation and ambipolar diffusion) MHD calculations to investigate the evolution of the magnetic field. We perform 288 runs in total and show the diversity of the density range within which the magnetic field effectively dissipates, depending on the environment. In addition, the dominant dissipation process (Ohmic dissipation or ambipolar diffusion) is shown to strongly depend on the star-forming environment. Especially, for the primordial case, magnetic field rarely dissipates without ionization source, while it efficiently dissipates when very weak ionization sources exist in the surrounding environment. The results of this study help to clarify star formation in various environments.

  6. Phylogenetic diversity of plants alters the effect of species richness on invertebrate herbivory

    PubMed Central

    2013-01-01

    Long-standing ecological theory proposes that diverse communities of plants should experience a decrease in herbivory. Yet previous empirical examinations of this hypothesis have revealed that plant species richness increases herbivory in just as many systems as it decreases it. In this study, I ask whether more insight into the role of plant diversity in promoting or suppressing herbivory can be gained by incorporating information about the evolutionary history of species in a community. In an old field system in southern Ontario, I surveyed communities of plants and measured levels of leaf damage on 27 species in 38 plots. I calculated a measure of phylogenetic diversity (PSE) that encapsulates information about the amount of evolutionary history represented in each of the plots and looked for a relationship between levels of herbivory and both species richness and phylogenetic diversity using a generalized linear mixed model (GLMM) that could account for variation in herbivory levels between species. I found that species richness was positively associated with herbivore damage at the plot-level, in keeping with the results from several other recent studies on this question. On the other hand, phylogenetic diversity was associated with decreased herbivory. Importantly, there was also an interaction between species richness and phylogenetic diversity, such that plots with the highest levels of herbivory were plots which had many species but only if those species tended to be closely related to one another. I propose that these results are the consequence of interactions with herbivores whose diets are phylogenetically specialized (for which I introduce the term cladophage), and how phylogenetic diversity may alter their realized host ranges. These results suggest that incorporating a phylogenetic perspective can add valuable additional insight into the role of plant diversity in explaining or predicting levels of herbivory at a whole-community scale. PMID:23825795

  7. Electron delocalization and charge mobility as a function of reduction in a metal-organic framework.

    PubMed

    Aubrey, Michael L; Wiers, Brian M; Andrews, Sean C; Sakurai, Tsuneaki; Reyes-Lillo, Sebastian E; Hamed, Samia M; Yu, Chung-Jui; Darago, Lucy E; Mason, Jarad A; Baeg, Jin-Ook; Grandjean, Fernande; Long, Gary J; Seki, Shu; Neaton, Jeffrey B; Yang, Peidong; Long, Jeffrey R

    2018-06-04

    Conductive metal-organic frameworks are an emerging class of three-dimensional architectures with degrees of modularity, synthetic flexibility and structural predictability that are unprecedented in other porous materials. However, engendering long-range charge delocalization and establishing synthetic strategies that are broadly applicable to the diverse range of structures encountered for this class of materials remain challenging. Here, we report the synthesis of K x Fe 2 (BDP) 3 (0 ≤ x ≤ 2; BDP 2-  = 1,4-benzenedipyrazolate), which exhibits full charge delocalization within the parent framework and charge mobilities comparable to technologically relevant polymers and ceramics. Through a battery of spectroscopic methods, computational techniques and single-microcrystal field-effect transistor measurements, we demonstrate that fractional reduction of Fe 2 (BDP) 3 results in a metal-organic framework that displays a nearly 10,000-fold enhancement in conductivity along a single crystallographic axis. The attainment of such properties in a K x Fe 2 (BDP) 3 field-effect transistor represents the realization of a general synthetic strategy for the creation of new porous conductor-based devices.

  8. Genetic diversity in butterflies: Interactive effects of habitat fragmentation and climate-driven range expansion.

    PubMed

    Hill, Jane K; Hughes, Clare L; Dytham, Calvin; Searle, Jeremy B

    2006-03-22

    Some species are expanding their ranges polewards during current climate warming. However, anthropogenic fragmentation of suitable habitat is affecting expansion rates and here we investigate interactions between range expansion, habitat fragmentation and genetic diversity. We examined three closely related Satyrinae butterflies, which differ in their habitat associations, from six sites along a transect in England from distribution core to expanding range margin. There was a significant decline in allozyme variation towards an expanding range margin in Pararge aegeria, which has the most restricted habitat availability, but not in Pyronia tithonus whose habitat is more widely available, or in a non-expanding 'control species' (Maniola jurtina). Moreover, data from another transect in Scotland indicated that declines in genetic diversity in P. aegeria were evident only on the transect in England, which had greater habitat fragmentation. Our results indicate that fragmentation of breeding habitats leads to more severe founder events during colonization, resulting in reduced diversity in marginal populations in more specialist species. The continued widespread loss of suitable habitats in the future may increase the likelihood of loss of genetic diversity in expanding species, which may affect whether or not species can adapt to future environmental change.

  9. The DEIMOS 10K Spectroscopic Survey Catalog of the COSMOS Field

    NASA Astrophysics Data System (ADS)

    Hasinger, G.; Capak, P.; Salvato, M.; Barger, A. J.; Cowie, L. L.; Faisst, A.; Hemmati, S.; Kakazu, Y.; Kartaltepe, J.; Masters, D.; Mobasher, B.; Nayyeri, H.; Sanders, D.; Scoville, N. Z.; Suh, H.; Steinhardt, C.; Yang, Fengwei

    2018-05-01

    We present a catalog of 10,718 objects in the COSMOS field, observed through multi-slit spectroscopy with the Deep Imaging Multi-Object Spectrograph (DEIMOS) on the Keck II telescope in the wavelength range ∼5500–9800 Å. The catalog contains 6617 objects with high-quality spectra (two or more spectral features), and 1798 objects with a single spectroscopic feature confirmed by the photometric redshift. For 2024 typically faint objects, we could not obtain reliable redshifts. The objects have been selected from a variety of input catalogs based on multi-wavelength observations in the field, and thus have a diverse selection function, which enables the study of the diversity in the galaxy population. The magnitude distribution of our objects is peaked at I AB ∼ 23 and K AB ∼ 21, with a secondary peak at K AB ∼ 24. We sample a broad redshift distribution in the range 0 < z < 6, with one peak at z ∼ 1, and another one around z ∼ 4. We have identified 13 redshift spikes at z > 0.65 with chance probabilities < 4 × 10‑4, some of which are clearly related to protocluster structures of sizes >10 Mpc. An object-to-object comparison with a multitude of other spectroscopic samples in the same field shows that our DEIMOS sample is among the best in terms of fraction of spectroscopic failures and relative redshift accuracy. We have determined the fraction of spectroscopic blends to about 0.8% in our sample. This is likely a lower limit and at any rate well below the most pessimistic expectations. Interestingly, we find evidence for strong lensing of Lyα background emitters within the slits of 12 of our target galaxies, increasing their apparent density by about a factor of 4. The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

  10. Bats, Trypanosomes, and Triatomines in Ecuador: New Insights into the Diversity, Transmission, and Origins of Trypanosoma cruzi and Chagas Disease.

    PubMed

    Pinto, C Miguel; Ocaña-Mayorga, Sofía; Tapia, Elicio E; Lobos, Simón E; Zurita, Alejandra P; Aguirre-Villacís, Fernanda; MacDonald, Amber; Villacís, Anita G; Lima, Luciana; Teixeira, Marta M G; Grijalva, Mario J; Perkins, Susan L

    2015-01-01

    The generalist parasite Trypanosoma cruzi has two phylogenetic lineages associated almost exclusively with bats-Trypanosoma cruzi Tcbat and the subspecies T. c. marinkellei. We present new information on the genetic variation, geographic distribution, host associations, and potential vectors of these lineages. We conducted field surveys of bats and triatomines in southern Ecuador, a country endemic for Chagas disease, and screened for trypanosomes by microscopy and PCR. We identified parasites at species and genotype levels through phylogenetic approaches based on 18S ribosomal RNA (18S rRNA) and cytochrome b (cytb) genes and conducted a comparison of nucleotide diversity of the cytb gene. We document for the first time T. cruzi Tcbat and T. c. marinkellei in Ecuador, expanding their distribution in South America to the western side of the Andes. In addition, we found the triatomines Cavernicola pilosa and Triatoma dispar sharing shelters with bats. The comparisons of nucleotide diversity revealed a higher diversity for T. c. marinkellei than any of the T. c. cruzi genotypes associated with Chagas disease. Findings from this study increased both the number of host species and known geographical ranges of both parasites and suggest potential vectors for these two trypanosomes associated with bats in rural areas of southern Ecuador. The higher nucleotide diversity of T. c. marinkellei supports a long evolutionary relationship between T. cruzi and bats, implying that bats are the original hosts of this important parasite.

  11. Bats, Trypanosomes, and Triatomines in Ecuador: New Insights into the Diversity, Transmission, and Origins of Trypanosoma cruzi and Chagas Disease

    PubMed Central

    Pinto, C. Miguel; Ocaña-Mayorga, Sofía; Tapia, Elicio E.; Lobos, Simón E.; Zurita, Alejandra P.; Aguirre-Villacís, Fernanda; MacDonald, Amber; Villacís, Anita G.; Lima, Luciana; Teixeira, Marta M. G.; Grijalva, Mario J.; Perkins, Susan L.

    2015-01-01

    The generalist parasite Trypanosoma cruzi has two phylogenetic lineages associated almost exclusively with bats—Trypanosoma cruzi Tcbat and the subspecies T. c. marinkellei. We present new information on the genetic variation, geographic distribution, host associations, and potential vectors of these lineages. We conducted field surveys of bats and triatomines in southern Ecuador, a country endemic for Chagas disease, and screened for trypanosomes by microscopy and PCR. We identified parasites at species and genotype levels through phylogenetic approaches based on 18S ribosomal RNA (18S rRNA) and cytochrome b (cytb) genes and conducted a comparison of nucleotide diversity of the cytb gene. We document for the first time T. cruzi Tcbat and T. c. marinkellei in Ecuador, expanding their distribution in South America to the western side of the Andes. In addition, we found the triatomines Cavernicola pilosa and Triatoma dispar sharing shelters with bats. The comparisons of nucleotide diversity revealed a higher diversity for T. c. marinkellei than any of the T. c. cruzi genotypes associated with Chagas disease. Findings from this study increased both the number of host species and known geographical ranges of both parasites and suggest potential vectors for these two trypanosomes associated with bats in rural areas of southern Ecuador. The higher nucleotide diversity of T. c. marinkellei supports a long evolutionary relationship between T. cruzi and bats, implying that bats are the original hosts of this important parasite. PMID:26465748

  12. Sympatric diversification vs. immigration: deciphering host-plant specialization in a polyphagous insect, the stolbur phytoplasma vector Hyalesthes obsoletus (Cixiidae).

    PubMed

    Imo, Miriam; Maixner, Michael; Johannesen, Jes

    2013-04-01

    The epidemiology of vector transmitted plant diseases is highly influenced by dispersal and the host-plant range of the vector. Widening the vector's host range may increase transmission potential, whereas specialization may induce specific disease cycles. The process leading to a vector's host shift and its epidemiological outcome is therefore embedded in the frameworks of sympatric evolution vs. immigration of preadapted populations. In this study, we analyse whether a host shift of the stolbur phytoplasma vector, Hyalesthes obsoletus from field bindweed to stinging nettle in its northern distribution range evolved sympatrically or by immigration. The exploitation of stinging nettle has led to outbreaks of the grapevine disease bois noir caused by a stinging nettle-specific phytoplasma strain. Microsatellite data from populations from northern and ancestral ranges provide strong evidence for sympatric host-race evolution in the northern range: Host-plant associated populations were significantly differentiated among syntopic sites (0.054 < F(HT) < 0.098) and constant over 5 years. While gene flow was asymmetric from the old into the predicted new host race, which had significantly reduced genetic diversity, the genetic identity between syntopic host-race populations in the northern range was higher than between these populations and syntopic populations in ancestral ranges, where there was no evidence for genetic host races. Although immigration was detected in the northern field bindweed population, it cannot explain host-race diversification but suggests the introduction of a stinging nettle-specific phytoplasma strain by plant-unspecific vectors. The evolution of host races in the northern range has led to specific vector-based bois noir disease cycles. © 2013 Blackwell Publishing Ltd.

  13. A Feedback Model of Attention Explains the Diverse Effects of Attention on Neural Firing Rates and Receptive Field Structure.

    PubMed

    Miconi, Thomas; VanRullen, Rufin

    2016-02-01

    Visual attention has many effects on neural responses, producing complex changes in firing rates, as well as modifying the structure and size of receptive fields, both in topological and feature space. Several existing models of attention suggest that these effects arise from selective modulation of neural inputs. However, anatomical and physiological observations suggest that attentional modulation targets higher levels of the visual system (such as V4 or MT) rather than input areas (such as V1). Here we propose a simple mechanism that explains how a top-down attentional modulation, falling on higher visual areas, can produce the observed effects of attention on neural responses. Our model requires only the existence of modulatory feedback connections between areas, and short-range lateral inhibition within each area. Feedback connections redistribute the top-down modulation to lower areas, which in turn alters the inputs of other higher-area cells, including those that did not receive the initial modulation. This produces firing rate modulations and receptive field shifts. Simultaneously, short-range lateral inhibition between neighboring cells produce competitive effects that are automatically scaled to receptive field size in any given area. Our model reproduces the observed attentional effects on response rates (response gain, input gain, biased competition automatically scaled to receptive field size) and receptive field structure (shifts and resizing of receptive fields both spatially and in complex feature space), without modifying model parameters. Our model also makes the novel prediction that attentional effects on response curves should shift from response gain to contrast gain as the spatial focus of attention drifts away from the studied cell.

  14. Changing geographic ranges of ticks and tick-borne pathogens: drivers, mechanisms and consequences for pathogen diversity

    PubMed Central

    Ogden, Nick H.; Mechai, Samir; Margos, Gabriele

    2013-01-01

    The geographic ranges of ticks and tick-borne pathogens are changing due to global and local environmental (including climatic) changes. In this review we explore current knowledge of the drivers for changes in the ranges of ticks and tick-borne pathogen species and strains via effects on their basic reproduction number (R0), and the mechanisms of dispersal that allow ticks and tick-borne pathogens to invade suitable environments. Using the expanding geographic distribution of the vectors and agent of Lyme disease as an example we then investigate what could be expected of the diversity of tick-borne pathogens during the process of range expansion, and compare this with what is currently being observed. Lastly we explore how historic population and range expansions and contractions could be reflected in the phylogeography of ticks and tick-borne pathogens seen in recent years, and conclude that combined study of currently changing tick and tick-borne pathogen ranges and diversity, with phylogeographic analysis, may help us better predict future patterns of invasion and diversity. PMID:24010124

  15. Changing geographic ranges of ticks and tick-borne pathogens: drivers, mechanisms and consequences for pathogen diversity.

    PubMed

    Ogden, Nick H; Mechai, Samir; Margos, Gabriele

    2013-01-01

    The geographic ranges of ticks and tick-borne pathogens are changing due to global and local environmental (including climatic) changes. In this review we explore current knowledge of the drivers for changes in the ranges of ticks and tick-borne pathogen species and strains via effects on their basic reproduction number (R 0), and the mechanisms of dispersal that allow ticks and tick-borne pathogens to invade suitable environments. Using the expanding geographic distribution of the vectors and agent of Lyme disease as an example we then investigate what could be expected of the diversity of tick-borne pathogens during the process of range expansion, and compare this with what is currently being observed. Lastly we explore how historic population and range expansions and contractions could be reflected in the phylogeography of ticks and tick-borne pathogens seen in recent years, and conclude that combined study of currently changing tick and tick-borne pathogen ranges and diversity, with phylogeographic analysis, may help us better predict future patterns of invasion and diversity.

  16. The type I fatty acid and polyketide synthases: a tale of two megasynthases

    PubMed Central

    Tsai, Shiou-Chuan

    2008-01-01

    This review chronicles the synergistic growth of the fields of fatty acid and polyketide synthesis over the last century. In both animal fatty acid synthases and modular polyketide synthases, similar catalytic elements are covalently linked in the same order in megasynthases. Whereas in fatty acid synthases the basic elements of the design remain immutable, guaranteeing the faithful production of saturated fatty acids, in the modular polyketide synthases, the potential of the basic design has been exploited to the full for the elaboration of a wide range of secondary metabolites of extraordinary structural diversity. PMID:17898897

  17. Developing an oropharyngeal cancer (OPC) knowledge and behaviors survey.

    PubMed

    Dodd, Virginia J; Riley Iii, Joseph L; Logan, Henrietta L

    2012-09-01

    To use the community participation research model to (1) develop a survey assessing knowledge about mouth and throat cancer and (2) field test and establish test-retest reliability with newly developed instrument. Cognitive interviews with primarily rural African American adults to assess their perception and interpretation of survey items. Test-retest reliability was established with a racially diverse rural population. Test-retest reliabilities ranged from .79 to .40 for screening awareness and .74 to .19 for knowledge. Coefficients increased for composite scores. Community participation methodology provided a culturally appropriate survey instrument that demonstrated acceptable levels of reliability.

  18. Using occupancy modelling to compare environmental DNA to traditional field methods for regional-scale monitoring of an endangered aquatic species.

    PubMed

    Schmelzle, Molly C; Kinziger, Andrew P

    2016-07-01

    Environmental DNA (eDNA) monitoring approaches promise to greatly improve detection of rare, endangered and invasive species in comparison with traditional field approaches. Herein, eDNA approaches and traditional seining methods were applied at 29 research locations to compare method-specific estimates of detection and occupancy probabilities for endangered tidewater goby (Eucyclogobius newberryi). At each location, multiple paired seine hauls and water samples for eDNA analysis were taken, ranging from two to 23 samples per site, depending upon habitat size. Analysis using a multimethod occupancy modelling framework indicated that the probability of detection using eDNA was nearly double (0.74) the rate of detection for seining (0.39). The higher detection rates afforded by eDNA allowed determination of tidewater goby occupancy at two locations where they have not been previously detected and at one location considered to be locally extirpated. Additionally, eDNA concentration was positively related to tidewater goby catch per unit effort, suggesting eDNA could potentially be used as a proxy for local tidewater goby abundance. Compared to traditional field sampling, eDNA provided improved occupancy parameter estimates and can be applied to increase management efficiency across a broad spatial range and within a diversity of habitats. © 2015 John Wiley & Sons Ltd.

  19. Irrigation and Maize Cultivation Erode Plant Diversity Within Crops in Mediterranean Dry Cereal Agro-Ecosystems.

    PubMed

    Fagúndez, Jaime; Olea, Pedro P; Tejedo, Pablo; Mateo-Tomás, Patricia; Gómez, David

    2016-07-01

    The intensification of agriculture has increased production at the cost of environment and biodiversity worldwide. To increase crop yield in dry cereal systems, vast farmland areas of high conservation value are being converted into irrigation, especially in Mediterranean countries. We analyze the effect of irrigation-driven changes on the farm biota by comparing species diversity, community composition, and species traits of arable plants within crop fields from two contrasting farming systems (dry and irrigated) in Spain. We sampled plant species within 80 fields of dry wheat, irrigated wheat, and maize (only cultivated under irrigation). Wheat crops held higher landscape and per field species richness, and beta diversity than maize. Within the same type of crop, irrigated wheat hosted lower plant diversity than dry wheat at both field and landscape scales. Floristic composition differed between crop types, with higher frequencies of perennials, cosmopolitan, exotic, wind-pollinated and C4 species in maize. Our results suggest that irrigation projects, that transform large areas of dry cereal agro-ecosystems into irrigated crop systems dominated by maize, erode plant diversity. An adequate planning on the type and proportion of crops used in the irrigated agro-ecosystems is needed in order to balance agriculture production and biodiversity conservation.

  20. What factors shape genetic diversity in cetaceans?

    PubMed

    Vachon, Felicia; Whitehead, Hal; Frasier, Timothy R

    2018-02-01

    Understanding what factors drive patterns of genetic diversity is a central aspect of many biological questions, ranging from the inference of historical demography to assessing the evolutionary potential of a species. However, as a larger number of datasets have become available, it is becoming clear that the relationship between the characteristics of a species and its genetic diversity is more complex than previously assumed. This may be particularly true for cetaceans, due to their relatively long lifespans, long generation times, complex social structures, and extensive ranges. In this study, we used microsatellite and mitochondrial DNA data from a systematic literature review to produce estimates of diversity for both markers across 42 cetacean species. Factors relating to demography, distribution, classification, biology, and behavior were then tested using phylogenetic methods and linear models to assess their relative influence on the genetic diversity of both marker types. The results show that while relative nuclear diversity is correlated with population size, mitochondrial diversity is not. This is particularly relevant given the widespread use of mitochondrial DNA to infer historical demography. Instead, mitochondrial diversity was mostly influenced by the range and social structure of the species. In addition to population size, habitat type (neritic vs. oceanic) had a significant correlation with relative nuclear diversity. Combined, these results show that many often-unconsidered factors are likely influencing patterns of genetic diversity in cetaceans, with implications regarding how to interpret, and what can be inferred from, existing patterns of diversity.

  1. Population genetics and the evolution of geographic range limits in an annual plant.

    PubMed

    Moeller, David A; Geber, Monica A; Tiffin, Peter

    2011-10-01

    Abstract Theoretical models of species' geographic range limits have identified both demographic and evolutionary mechanisms that prevent range expansion. Stable range limits have been paradoxical for evolutionary biologists because they represent locations where populations chronically fail to respond to selection. Distinguishing among the proposed causes of species' range limits requires insight into both current and historical population dynamics. The tools of molecular population genetics provide a window into the stability of range limits, historical demography, and rates of gene flow. Here we evaluate alternative range limit models using a multilocus data set based on DNA sequences and microsatellites along with field demographic data from the annual plant Clarkia xantiana ssp. xantiana. Our data suggest that central and peripheral populations have very large historical and current effective population sizes and that there is little evidence for population size changes or bottlenecks associated with colonization in peripheral populations. Whereas range limit populations appear to have been stable, central populations exhibit a signature of population expansion and have contributed asymmetrically to the genetic diversity of peripheral populations via migration. Overall, our results discount strictly demographic models of range limits and more strongly support evolutionary genetic models of range limits, where adaptation is prevented by a lack of genetic variation or maladaptive gene flow.

  2. Access for All Customers: Universal Strategies for One-Stop Career Centers. The Institute Brief. Issue Number 26

    ERIC Educational Resources Information Center

    Hoff, David; Varney, Elena; Enein-Donovan, Lara; Thomas, Cindy; Fesko, Sheila

    2009-01-01

    One-Stop Career Centers serve a diverse range of customers. These include individuals with a variety of educational and work backgrounds, people from diverse racial, linguistic and ethnic cultures, as well as individuals with a wide range of disabilities and support needs. One way of addressing the needs of this diverse customer base is to develop…

  3. Early Experiences and Integration in the Persistence of First-Generation College Students in STEM and Non-STEM Majors

    ERIC Educational Resources Information Center

    Dika, Sandra L.; D'Amico, Mark M.

    2016-01-01

    Representation of diverse groups in science, technology, engineering, and mathematics (STEM) fields is a persistent concern in the United States. Although there have been some strides toward more diverse representation, significant problems of underrepresentation remain in particular STEM fields: physical sciences, engineering, math, and computer…

  4. Fostering Knowledge and Skills to Teach for Diversity: "There Is Nothing so Practical as a Good Theory"

    ERIC Educational Resources Information Center

    Marchel, Carol A.; Green, Susan K

    2014-01-01

    Increased use of field-based teacher preparation offers important opportunities to develop skills with diverse learners. However, limited focus on theoretical content restricts understanding and generalization of well-proven theoretical approaches, resulting in fragmented field applications unlikely to result in broad application. Inspired by Kurt…

  5. The Role of Majority Groups in Diversity Programs

    ERIC Educational Resources Information Center

    Rheingans, Penny; Brodsky, Anne; Scheibler, Jill; Spence, Anne

    2011-01-01

    The underrepresentation of women in technical fields is a widely acknowledged national problem, limiting both the raw size of the talent pool and the diversity of experiences and perspectives of those who will design solutions to key problems facing society. Empowering women to succeed in these fields is clearly one important component of any…

  6. A resurgence in field research is essential to better understand the diversity, ecology, and evolution of microbial eukaryotes.

    PubMed

    Heger, Thierry J; Edgcomb, Virginia P; Kim, Eunsoo; Lukeš, Julius; Leander, Brian S; Yubuki, Naoji

    2014-01-01

    The discovery and characterization of protist communities from diverse environments are crucial for understanding the overall evolutionary history of life on earth. However, major questions about the diversity, ecology, and evolutionary history of protists remain unanswered, notably because data obtained from natural protist communities, especially of heterotrophic species, remain limited. In this review, we discuss the challenges associated with "field protistology", defined here as the exploration, characterization, and interpretation of microbial eukaryotic diversity within the context of natural environments or field experiments, and provide suggestions to help fill this important gap in knowledge. We also argue that increased efforts in field studies that combine molecular and microscopical methods offer the most promising path toward (1) the discovery of new lineages that expand the tree of eukaryotes; (2) the recognition of novel evolutionary patterns and processes; (3) the untangling of ecological interactions and functions, and their roles in larger ecosystem processes; and (4) the evaluation of protist adaptations to a changing climate. © 2013 The Author(s) Journal of Eukaryotic Microbiology © 2013 International Society of Protistologists.

  7. Climate-driven range shifts explain the distribution of extant gene pools and predict future loss of unique lineages in a marine brown alga.

    PubMed

    Assis, J; Serrão, E A; Claro, B; Perrin, C; Pearson, G A

    2014-06-01

    The climate-driven dynamics of species ranges is a critical research question in evolutionary ecology. We ask whether present intraspecific diversity is determined by the imprint of past climate. This is an ongoing debate requiring interdisciplinary examination of population genetic pools and persistence patterns across global ranges. Previously, contrasting inferences and predictions have resulted from distinct genomic coverage and/or geographical information. We aim to describe and explain the causes of geographical contrasts in genetic diversity and their consequences for the future baseline of the global genetic pool, by comparing present geographical distribution of genetic diversity and differentiation with predictive species distribution modelling (SDM) during past extremes, present time and future climate scenarios for a brown alga, Fucus vesiculosus. SDM showed that both atmospheric and oceanic variables shape the global distribution of intertidal species, revealing regions of persistence, extinction and expansion during glacial and postglacial periods. These explained the distribution and structure of present genetic diversity, consisting of differentiated genetic pools with maximal diversity in areas of long-term persistence. Most of the present species range comprises postglacial expansion zones and, in contrast to highly dispersive marine organisms, expansions involved only local fronts, leaving distinct genetic pools at rear edges. Besides unravelling a complex phylogeographical history and showing congruence between genetic diversity and persistent distribution zones, supporting the hypothesis of niche conservatism, range shifts and loss of unique genetic diversity at the rear edge were predicted for future climate scenarios, impoverishing the global gene pool. © 2014 John Wiley & Sons Ltd.

  8. Realising the Benefits of Adopting and Adapting Existing CF Metadata Conventions to a Broader Range of Geoscience Data

    NASA Astrophysics Data System (ADS)

    Druken, K. A.; Trenham, C. E.; Wang, J.; Bastrakova, I.; Evans, B. J. K.; Wyborn, L. A.; Ip, A. I.; Poudjom Djomani, Y.

    2016-12-01

    The National Computational Infrastructure (NCI) hosts one of Australia's largest repositories (10+ PBytes) of research data, colocated with a petascale High Performance Computer and a highly integrated research cloud. Key to maximizing benefit of NCI's collections and computational capabilities is ensuring seamless interoperable access to these datasets. This presents considerable data management challenges across the diverse range of geoscience data; spanning disciplines where netCDF-CF is commonly utilized (e.g., climate, weather, remote-sensing), through to the geophysics and seismology fields that employ more traditional domain- and study-specific data formats. These data are stored in a variety of gridded, irregularly spaced (i.e., trajectories, point clouds, profiles), and raster image structures. They often have diverse coordinate projections and resolutions, thus complicating the task of comparison and inter-discipline analysis. Nevertheless, much can be learned from the netCDF-CF model that has long served the climate community, providing a common data structure for the atmospheric, ocean and cryospheric sciences. We are extending the application of the existing Climate and Forecast (CF) metadata conventions to NCI's broader geoscience data collections. We present simple implementations that can significantly improve interoperability of the research collections, particularly in the case of line survey data. NCI has developed a compliance checker to assist with the data quality across all hosted netCDF-CF collections. The tool is an extension to one of the main existing CF Convention checkers, that we have modified to incorporate the Attribute Convention for Data Discovery (ACDD) and ISO19115 standards, and to perform parallelised checks over collections of files, ensuring compliance and consistency across the NCI data collections as a whole. It is complemented by a checker that also verifies functionality against a range of scientific analysis, programming, and data visualisation tools. By design, these tests are not necessarily domain-specific, and demonstrate that verified data is accessible to end-users, thus allowing for seamless interoperability with other datasets across a wide range of fields.

  9. Exploring diversity in ensemble classification: Applications in large area land cover mapping

    NASA Astrophysics Data System (ADS)

    Mellor, Andrew; Boukir, Samia

    2017-07-01

    Ensemble classifiers, such as random forests, are now commonly applied in the field of remote sensing, and have been shown to perform better than single classifier systems, resulting in reduced generalisation error. Diversity across the members of ensemble classifiers is known to have a strong influence on classification performance - whereby classifier errors are uncorrelated and more uniformly distributed across ensemble members. The relationship between ensemble diversity and classification performance has not yet been fully explored in the fields of information science and machine learning and has never been examined in the field of remote sensing. This study is a novel exploration of ensemble diversity and its link to classification performance, applied to a multi-class canopy cover classification problem using random forests and multisource remote sensing and ancillary GIS data, across seven million hectares of diverse dry-sclerophyll dominated public forests in Victoria Australia. A particular emphasis is placed on analysing the relationship between ensemble diversity and ensemble margin - two key concepts in ensemble learning. The main novelty of our work is on boosting diversity by emphasizing the contribution of lower margin instances used in the learning process. Exploring the influence of tree pruning on diversity is also a new empirical analysis that contributes to a better understanding of ensemble performance. Results reveal insights into the trade-off between ensemble classification accuracy and diversity, and through the ensemble margin, demonstrate how inducing diversity by targeting lower margin training samples is a means of achieving better classifier performance for more difficult or rarer classes and reducing information redundancy in classification problems. Our findings inform strategies for collecting training data and designing and parameterising ensemble classifiers, such as random forests. This is particularly important in large area remote sensing applications, for which training data is costly and resource intensive to collect.

  10. The evolution and future of diversity at work.

    PubMed

    Roberson, Quinetta; Ryan, Ann Marie; Ragins, Belle Rose

    2017-03-01

    This article examines the evolution of diversity in the Journal of Applied Psychology. To begin, we explore foundations of the concept of diversity, including its appearance in both applied contexts and the scholarly literature. We then review the literature on diversity, including the development of its conceptualization and operationalizations over time, in the Journal and in the field of applied psychological science at large. We also examine the processes underlying the effects of diversity, and specific outcomes of diversity in organizations. To conclude, we offer a future research agenda that highlights diversity-related topics and issues important for advancing an understanding of diversity and moving the field forward, especially within the Journal. This work makes several contributions to research on diversity in organizations. First, we provide a lens for examining change in the study of diversity over time as well as a critical examination of the benefits and challenges associated with these changes. Second, we review the underlying mechanisms and key contextual influences on diversity effects in organizations. Third, our review examines the explanatory power of current diversity research and then uses this to develop a research agenda. By organizing the broad body of literature that exists on diversity, our article offers a sharp picture of what gaps in knowledge exist and where future research should focus. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  11. Reflections on Field Experiences Related to Diversity Issues: Illinois State's Undergrad FCS Teaching Methods Course

    ERIC Educational Resources Information Center

    Banning, Jennifer

    2013-01-01

    This study documents what pre-service family and consumer sciences (FCS) teachers learned about diversity through observations in diverse FCS classrooms. Students reported that they experienced a change in their comfort level with diverse settings. Student feedback was used to modify FCS teacher education curriculum in subsequent semesters.

  12. Critical Examination of Candidates' Diversity Competence: Rigorous and Systematic Assessment of Candidates' Efficacy to Teach Diverse Student Populations

    ERIC Educational Resources Information Center

    Benton-Borghi, Beatrice Hope; Chang, Young Mi

    2011-01-01

    The National Center for Educational Statistics (NCES, 2010) continues to report substantial underachievement of diverse student populations in the nation's schools. After decades of focus on diversity and multicultural education, with integrating field and clinical practice, candidates continue to graduate without adequate knowledge, skills and…

  13. Recruitment of Diverse Students in School Psychology Programs: Direction for Future Research and Practice

    ERIC Educational Resources Information Center

    Proctor, Sherrie L.; Simpson, Chamane M.; Levin, Jacqueline; Hackimer, Laura

    2014-01-01

    Lack of racially, ethnically, and linguistically (REL) diverse school psychologists has been a concern for decades. Recent and rapid increases in student diversity within America's public schools require that school psychology address the longstanding lack of diversity within the field. This article details the demographics of school…

  14. From voice to voices: identifying a plurality of Muslim sources in the news media.

    PubMed

    Munnik, Michael B

    2017-03-01

    This article identifies a qualitative change in the diversity of actors who represent Muslims in British news media. Hitherto, the literature discussing Muslims and the media has tended to characterize media organizations as institutions which portray Muslims in an essentialized, monolithic way. In contrast, I propose in this article that the process of representation is more complex, including greater agency and engaging a wider diversity of Muslims than the prevailing literature suggests. Sociological studies distinguish between official and unofficial sources who help determine the representations that journalists employ in their texts, and I apply this to Muslim communities in Glasgow. Using qualitative methods drawn from media production analysis, including participant-observation and ethnographic interviews, I identify a shift from a 'gatekeeper' model of representing the community to that of a plurality of sources, which reveals and insists on the diversity of Muslim communities and voices. I will show why a wider range of actors emerged to speak publicly, what differentiates them and how they position themselves as representatives of Muslims. This focus on producers and on source strategies brings fresh insights into a field dominated by content analysis and a 'media-centric' approach.

  15. From voice to voices: identifying a plurality of Muslim sources in the news media

    PubMed Central

    Munnik, Michael B

    2017-01-01

    This article identifies a qualitative change in the diversity of actors who represent Muslims in British news media. Hitherto, the literature discussing Muslims and the media has tended to characterize media organizations as institutions which portray Muslims in an essentialized, monolithic way. In contrast, I propose in this article that the process of representation is more complex, including greater agency and engaging a wider diversity of Muslims than the prevailing literature suggests. Sociological studies distinguish between official and unofficial sources who help determine the representations that journalists employ in their texts, and I apply this to Muslim communities in Glasgow. Using qualitative methods drawn from media production analysis, including participant-observation and ethnographic interviews, I identify a shift from a ‘gatekeeper’ model of representing the community to that of a plurality of sources, which reveals and insists on the diversity of Muslim communities and voices. I will show why a wider range of actors emerged to speak publicly, what differentiates them and how they position themselves as representatives of Muslims. This focus on producers and on source strategies brings fresh insights into a field dominated by content analysis and a ‘media-centric’ approach. PMID:29708127

  16. Short-term invasibility patterns in burnt and unburnt experimental Mediterranean grassland communities of varying diversities.

    PubMed

    Dimitrakopoulos, Panayiotis G; Galanidis, Alexandros; Siamantziouras, Akis-Stavros D; Troumbis, Andreas Y

    2005-04-01

    This paper reports the findings of a short-term natural invasibility field study in constructed Mediterranean herbaceous communities of varying diversities, under a fire treatment. Three components of invasibility, i.e. species richness, density and biomass of invaders, have been monitored in burnt and unburnt experimental plots with resident diversity ranging from monocultures to 18-species mixtures. In general, species richness, density and biomass of invaders decreased significantly with the increase of resident species richness. Furthermore, the density and biomass of invading species were significantly influenced by the species composition of resident communities. Although aboveground biomass, leaf area index, canopy height and percent bare ground of the resident communities explained a significant part of the variation in the success of invading species, these covariates did not fully explain the effects of resident species richness. Fire mainly influenced invasibility via soil nutrient levels. The effect of fire on observed invasibility patterns seems to be less important than the effects of resident species richness. Our results demonstrate the importance of species richness and composition in controlling the initial stages of plant invasions in Mediterranean grasslands but that there was a lack of interaction with the effects of fire disturbance.

  17. Identifying Cellular and Molecular Mechanisms for Magnetosensation

    PubMed Central

    Clites, Benjamin L.; Pierce, Jonathan T.

    2017-01-01

    Diverse animals ranging from worms and insects to birds and turtles perf orm impressive journeys using the magnetic field of the earth as a cue. Although major cellular and molecular mechanisms for sensing mechanical and chemical cues have been elucidated over the past three decades, the mechanisms that animals use to sense magnetic fields remain largely mysterious. Here we survey progress on the search for magnetosensory neurons and magnetosensitive molecules important for animal behaviors. Emphasis is placed on magnetosensation in insects and birds, as well as on the magnetosensitive neuron pair AFD in the nematode Caenorhabditis elegans. We also review conventional criteria used to define animal magnetoreceptors and suggest how approaches used to identify receptors for other sensory modalities may be adapted for magnetoreceptors. Finally, we discuss prospects for under-utilized and novel approaches to identify the elusive magnetoreceptors in animals. PMID:28772099

  18. KSC-08pd2397

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, technicians monitor the movement of the Wide Field Camera 3, or WFC3, as it is lowered onto a work stand. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  19. KSC-08pd2396

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, technicians monitor the movement of the Wide Field Camera 3, or WFC3, as the overhead crane transfers it to a work stand. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  20. KSC-08pd2383

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, the cover of the Wide Field Camera 3, or WFC3, shipping container is lifted away from the mobile base. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  1. KSC-08pd2392

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, technicians move the base of the shipping container holding the Wide Field Camera 3, or WFC3, into the high bay. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  2. KSC-08pd2391

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, technicians move the base of the shipping container holding the Wide Field Camera 3, or WFC3. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  3. KSC-08pd2398

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, technicians monitor the placement of the Wide Field Camera 3, or WFC3, on a work stand. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  4. KSC-08pd2450

    NASA Image and Video Library

    2008-08-16

    CAPE CANAVERAL, Fla. – Technicians in the Payload Hazardous Servicing Facility remove the protective cover from the Wide Field Camera 3, or WFC3. The WFC3 is part of the payload on space shuttle Atlantis for the fifth and final Hubble servicing mission, STS-125. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Jack Pfaller

  5. KSC-08pd2381

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, technicians attach an overhead crane to the cover of the Wide Field Camera 3, or WFC3, shipping container. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  6. KSC-08pd2449

    NASA Image and Video Library

    2008-08-16

    CAPE CANAVERAL, Fla. – Technicians in the Payload Hazardous Servicing Facility begin removing the protective cover from the Wide Field Camera 3, or WFC3. The WFC3 is part of the payload on space shuttle Atlantis for the fifth and final Hubble servicing mission, STS-125. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Jack Pfaller

  7. KSC-08pd2378

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – The shipping container with the Wide Field Camera 3, or WFC3, inside is removed from the truck outside the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  8. KSC-08pd2382

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, technicians begin lifting the cover of the Wide Field Camera 3, or WFC3, shipping container. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  9. KSC-08pd2379

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, technicians unlatch the cover of the Wide Field Camera 3, or WFC3,shipping container before removing it. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  10. Determination of plant growth rate and growth temperature range from measurement of physiological parameters

    Treesearch

    R. S. Criddle; B. N. Smith; L. D. Hansen; J. N. Church

    2001-01-01

    Many factors influence species range and diversity, but temperature and temperature variability are always major global determinants, irrespective of local constraints. On a global scale, the ranges of many taxa have been observed to increase and their diversity decrease with increasing latitude. On a local scale, gradients in species distribution are observable with...

  11. The strengths of r- and K-selection shape diversity-disturbance relationships.

    PubMed

    Bohn, Kristin; Pavlick, Ryan; Reu, Björn; Kleidon, Axel

    2014-01-01

    Disturbance is a key factor shaping species abundance and diversity in plant communities. Here, we use a mechanistic model of vegetation diversity to show that different strengths of r- and K-selection result in different disturbance-diversity relationships. R- and K-selection constrain the range of viable species through the colonization-competition tradeoff, with strong r-selection favoring colonizers and strong K-selection favoring competitors, but the level of disturbance also affects the success of species. This interplay among r- and K-selection and disturbance results in different shapes of disturbance-diversity relationships, with little variation of diversity with no r- and no K-selection, a decrease in diversity with r-selection with disturbance rate, an increase in diversity with K-selection, and a peak at intermediate values with strong r- and K-selection. We conclude that different disturbance-diversity relationships found in observations may reflect different intensities of r- and K-selection within communities, which should be inferable from broader observations of community composition and their ecophysiological trait ranges.

  12. Quantifying understorey vegetation in the US Lake States: a proposed framework to inform regional forest carbon stocks

    USGS Publications Warehouse

    Russell, Matthew B.; D'Amato, Anthony W.; Schulz, Bethany K.; Woodall, Christopher W.; Domke, Grant M.; Bradford, John B.

    2014-01-01

    The contribution of understorey vegetation (UVEG) to forest ecosystem biomass and carbon (C) across diverse forest types has, to date, eluded quantification at regional and national scales. Efforts to quantify UVEG C have been limited to field-intensive studies or broad-scale modelling approaches lacking field measurements. Although large-scale inventories of UVEG C are not common, species- and community-level inventories of vegetation structure are available and may prove useful in quantifying UVEG C stocks. This analysis developed a general framework for estimating UVEG C stocks by employing per cent cover estimates of UVEG from a region-wide forest inventory coupled with an estimate of maximum UVEG C across the US Lake States (i.e. Michigan, Minnesota and Wisconsin). Estimates of UVEG C stocks from this approach reasonably align with expected C stocks in the study region, ranging from 0.86 ± 0.06 Mg ha-1 in red pine-dominated to 1.59 ± 0.06 Mg ha-1 for aspen/birch-dominated forest types. Although the data employed here were originally collected to assess broad-scale forest structure and diversity, this study proposes a framework for using UVEG inventories as a foundation for estimating C stocks in an often overlooked, yet important ecosystem C pool.

  13. Ecology, Microbial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Konopka, Allan

    2009-05-15

    Microbial ecology is a relatively young discipline within the field of microbiology. Its modern history spans just the past 60 years, and the field is defined by its emphasis on understanding the interactions of microbes with their environment, rather than their behavior under artificial laboratory conditions. Because microbes are ubiquitous, microbial ecologists study a broad diversity of habitats that range from aquatic to terrestrial to plant- or animal-associated. This has made it a challenge to identify unifying principles within the field. One approach is to recognize that although the activity of microbes in nature have effects at the macroscale, theymore » interact with their physical, chemical and biological milieu at a scale of micrometers. At this scale, several different microbial ecosystems can be defined, based upon association with particles, the presence of environmental gradients and the continuous availability of water. Principles applicable to microbial ecology reflect not only their population ecology and physiological ecology, but also their broad versatility and quantitative importance in the biosphere as biogeochemical catalysts and capacity for rapid physiological and evolutionary responses.« less

  14. Towards an Automated Acoustic Detection System for Free Ranging Elephants.

    PubMed

    Zeppelzauer, Matthias; Hensman, Sean; Stoeger, Angela S

    The human-elephant conflict is one of the most serious conservation problems in Asia and Africa today. The involuntary confrontation of humans and elephants claims the lives of many animals and humans every year. A promising approach to alleviate this conflict is the development of an acoustic early warning system. Such a system requires the robust automated detection of elephant vocalizations under unconstrained field conditions. Today, no system exists that fulfills these requirements. In this paper, we present a method for the automated detection of elephant vocalizations that is robust to the diverse noise sources present in the field. We evaluate the method on a dataset recorded under natural field conditions to simulate a real-world scenario. The proposed method outperformed existing approaches and robustly and accurately detected elephants. It thus can form the basis for a future automated early warning system for elephants. Furthermore, the method may be a useful tool for scientists in bioacoustics for the study of wildlife recordings.

  15. Broadband and Wide Field-of-view Plasmonic Metasurface-enabled Waveplates

    PubMed Central

    Jiang, Zhi Hao; Lin, Lan; Ma, Ding; Yun, Seokho; Werner, Douglas H.; Liu, Zhiwen; Mayer, Theresa S.

    2014-01-01

    Quasi two-dimensional metasurfaces composed of subwavelength nanoresonator arrays can dramatically alter the properties of light in an ultra-thin planar geometry, enabling new optical functions such as anomalous reflection and refraction, polarization filtering, and wavefront modulation. However, previous metasurface-based nanostructures suffer from low efficiency, narrow bandwidth and/or limited field-of-view due to their operation near the plasmonic resonance. Here we demonstrate plasmonic metasurface-based nanostructures for high-efficiency, angle-insensitive polarization transformation over a broad octave-spanning bandwidth. The structures are realized by optimizing the anisotropic response of an array of strongly coupled nanorod resonators to tailor the interference of light at the subwavelength scale. Nanofabricated reflective half-wave and quarter-wave plates designed using this approach have measured polarization conversion ratios and reflection magnitudes greater than 92% over a broad wavelength range from 640 to 1290 nm and a wide field-of-view up to ±40°. This work outlines a versatile strategy to create metasurface-based photonics with diverse optical functionalities. PMID:25524830

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Konopka, Allan

    Microbial ecology is a relatively young discipline within the field of microbiology. Its modern history spans just the past 60 years, and the field is defined by its emphasis on understanding the interactions of microbes with their environment, rather than their behavior under artificial laboratory conditions. Because microbes are ubiquitous, microbial ecologists study a broad diversity of habitats that range from aquatic to terrestrial to plant- or animal-associated. This has made it a challenge to identify unifying principles within the field. One approach is to recognize that although the activity of microbes in nature have effects at the macroscale, theymore » interact with their physical, chemical and biological milieu at a scale of micrometers. At this scale, several different microbial ecosystems can be defined, based upon association with particles, the presence of environmental gradients and the continuous availability of water. Principles applicable to microbial ecology reflect not only their population ecology and physiological ecology, but also their broad versatility and quantitative importance in the biosphere as biogeochemical catalysts and capacity for rapid physiological and evolutionary responses.« less

  17. The Influence of Landscape Heterogeneity - Ground Beetles (Coleoptera: Carabidae) in Fthiotida, Central Greece

    PubMed Central

    2014-01-01

    Abstract Pitfall traps were used to sample Carabidae in agricultural land of the Spercheios valley, Fthiotida, Central Greece. Four pairs of cultivated fields were sampled. One field of each pair was located in a heterogeneous area and the other in a more homogeneous area. Heterogeneous areas were composed of small fields. They had high percentages of non-cropped habitats and a high diversity of land use types. Homogeneous areas were composed of larger fields. They had lower percentages of non-cropped habitats and a lower diversity of land use types. One pair of fields had been planted with cotton, one with maize, one with olives and one with wheat. Altogether 28 carabid species were recorded. This paper describes the study areas, the sampling methods used and presents the data collected during the study. Neither heterogeneous nor homogeneous areas had consistently higher abundance levels, activity density levels, species richness levels or diversity levels. However, significant differences were seen in some of the comparisons between heterogeneous and homogeneous areas. PMID:24891833

  18. Genetic diversity of the Arctic fox using SRAP markers.

    PubMed

    Zhang, M; Bai, X J

    2013-12-04

    Sequence-related amplified polymorphism (SRAP) is a recently developed molecular marker technique that is stable, simple, reliable, and achieves moderate to high numbers of codominant markers. This study is the first to apply SRAP markers in a mammal, namely the Arctic fox. In order to investigate the genetic diversity of the Arctic fox and to provide a reference for use of its germplasm, we analyzed 7 populations of Arctic fox by SRAP. The genetic similarity coefficient, genetic distance, proportion of polymorphic loci, total genetic diversity (Ht), genetic diversity within populations (Hs), and genetic differentiation (Gst) were calculated using the Popgene software package. The results indicated abundant genetic diversity among the different populations of Arctic fox studied in China. The genetic similarity coefficient ranged from 0.1694 to 0.0417, genetic distance ranged from 0.8442 to 0.9592, and the proportion of polymorphic loci was smallest in the TS group. Genetic diversity ranged from 0.2535 to 0.3791, Ht was 0.3770, Hs was 0.3158, Gst was 0.1624, and gene flow (Nm) was estimated at 2.5790. Thus, a high level of genetic diversity and many genetic relationships were found in the populations of Arctic fox evaluated in this study.

  19. Genomic diversity of the Avian leukosis virus subgroup J gp85 gene in different organs of an infected chicken.

    PubMed

    Meng, Fanfeng; Li, Xue; Fang, Jian; Gao, Yalong; Zhu, Lilong; Xing, Guiju; Tian, Fu; Gao, Yali; Dong, Xuan; Chang, Shuang; Zhao, Peng; Cui, Zhizhong; Liu, Zhihao

    2016-12-30

    The genomic diversity of Avian leukosis virus subgroup J (ALV-J) was investigated in an experimentally infected chicken. ALV-J variants in tissues from four different organs of the same bird were re-isolated in DF-1 cells, and their gp85 gene was amplified and cloned. Ten clones from each organ were sequenced and compared with the original inoculum strain, NX0101. The minimum homology of each organ ranged from 96.7 to 97.6%, and the lowest homology between organs was only 94.9%, which was much lower than the 99.1% homology of inoculum NX0101, indicating high diversity of ALV-J, even within the same bird. The gp85 mutations from the left kidney, which contained tumors, and the right kidney, which was tumor-free, had higher non-synonymous to synonymous mutation ratios than those in the tumor-bearing liver and lungs. Additionally, the mutational sites of gp85 gene in the kidney were similar, and they differed from those in the liver and lung, implying that organ- or tissue-specific selective pressure had a greater influence on the evolution of ALV-J diversity. These results suggest that more ALV-J clones from different organs and tissues should be sequenced and compared to better understand viral evolution and molecular epidemiology in the field.

  20. Soft Coral Sarcophyton (Cnidaria: Anthozoa: Octocorallia) Species Diversity and Chemotypes

    PubMed Central

    Aratake, Satoe; Tomura, Tomohiko; Saitoh, Seikoh; Yokokura, Ryouma; Kawanishi, Yuichi; Shinjo, Ryuichi; Reimer, James Davis; Tanaka, Junichi; Maekawa, Hideaki

    2012-01-01

    Research on the soft coral genus Sarcophyton extends over a wide range of fields, including marine natural products and the isolation of a number of cembranoid diterpenes. However, it is still unknown how soft corals produce this diverse array of metabolites, and the relationship between soft coral diversity and cembranoid diterpene production is not clear. In order to understand this relationship, we examined Sarcophyton specimens from Okinawa, Japan, by utilizing three methods: morphological examination of sclerites, chemotype identification, and phylogenetic examination of both Sarcophyton (utilizing mitochondrial protein-coding genes MutS homolog: msh1) and their endosymbiotic Symbiodinium spp. (utilizing nuclear internal transcribed spacer of ribosomal DNA: ITS- rDNA). Chemotypes, molecular phylogenetic clades, and sclerites of Sarcophyton trocheliophorum specimens formed a clear and distinct group, but the relationships between chemotypes, molecular phylogenetic clade types and sclerites of the most common species, Sarcophyton glaucum, was not clear. S. glaucum was divided into four clades. A characteristic chemotype was observed within one phylogenetic clade of S. glaucum. Identities of symbiotic algae Symbiodinium spp. had no apparent relation to chemotypes of Sarcophyton spp. This study demonstrates that the complex results observed for S. glaucum are due to the incomplete and complex taxonomy of this species group. Our novel method of identification should help contribute to classification and taxonomic reassessment of this diverse soft coral genus. PMID:22272344

  1. Soft coral Sarcophyton (Cnidaria: Anthozoa: Octocorallia) species diversity and chemotypes.

    PubMed

    Aratake, Satoe; Tomura, Tomohiko; Saitoh, Seikoh; Yokokura, Ryouma; Kawanishi, Yuichi; Shinjo, Ryuichi; Reimer, James Davis; Tanaka, Junichi; Maekawa, Hideaki

    2012-01-01

    Research on the soft coral genus Sarcophyton extends over a wide range of fields, including marine natural products and the isolation of a number of cembranoid diterpenes. However, it is still unknown how soft corals produce this diverse array of metabolites, and the relationship between soft coral diversity and cembranoid diterpene production is not clear. In order to understand this relationship, we examined Sarcophyton specimens from Okinawa, Japan, by utilizing three methods: morphological examination of sclerites, chemotype identification, and phylogenetic examination of both Sarcophyton (utilizing mitochondrial protein-coding genes MutS homolog: msh1) and their endosymbiotic Symbiodinium spp. (utilizing nuclear internal transcribed spacer of ribosomal DNA: ITS- rDNA). Chemotypes, molecular phylogenetic clades, and sclerites of Sarcophyton trocheliophorum specimens formed a clear and distinct group, but the relationships between chemotypes, molecular phylogenetic clade types and sclerites of the most common species, Sarcophyton glaucum, was not clear. S. glaucum was divided into four clades. A characteristic chemotype was observed within one phylogenetic clade of S. glaucum. Identities of symbiotic algae Symbiodinium spp. had no apparent relation to chemotypes of Sarcophyton spp. This study demonstrates that the complex results observed for S. glaucum are due to the incomplete and complex taxonomy of this species group. Our novel method of identification should help contribute to classification and taxonomic reassessment of this diverse soft coral genus.

  2. Comparison of genetic diversity and population structure between two Schistosoma japonicum isolates--the field and the laboratory.

    PubMed

    Bian, Chao-Rong; Gao, Yu-Meng; Lamberton, Poppy H L; Lu, Da-Bing

    2015-06-01

    Schistosomiasis japonicum is one of the most important human parasitic diseases, and a number of studies have recently elucidated the difference in biological characteristics of S. japonicum among different parasite isolates, for example, between the field and the laboratory isolates. Therefore, the understanding of underlying genetic mechanism is of both theoretical and practical importance. In this study, we used six microsatellite markers to assess genetic diversity, population structure, and the bottleneck effect (a sharp reduction in population size) of two parasite populations, one field and one laboratory. A total of 136 S. japonicum cercariae from the field and 86 from the laboratory, which were genetically unique within single snails, were analyzed. The results showed bigger numbers of alleles and higher allelic richness in the field parasite population than in the laboratory indicating lower genetic diversity in the laboratory parasites. A bottleneck effect was detected in the laboratory population. When the field and laboratory isolates were combined, there was a clear distinction between two parasite populations using the software Structure. These genetic differences may partially explain the previously observed contrasted biological traits.

  3. James M. Kauffman's Ideas about Special Education: Implications for Educating Culturally and Linguistically Diverse Students

    ERIC Educational Resources Information Center

    Tetzloff, Lynn; Obiakor, Festus E.

    2015-01-01

    For decades, James M. Kauffman has been a reputable scholar in the field of special education. While his contributions to the field cannot be doubted, his ideas about special education have been somewhat controversial and even devastating to the education of culturally and linguistically diverse (CLD) learners with and without disabilities.…

  4. Purposes, Diversities, and Futures in MFT Doctoral Education

    ERIC Educational Resources Information Center

    Woolley, Scott R.

    2010-01-01

    Doctoral education in marital and family therapy (MFT) plays a crucial role in the future of the field. In this article, I write about the purposes, diversities, and futures of MFT doctoral education from the perspective of having hired 18 full-time MFT faculty over the last 13 years. I argue that the field needs well-rounded doctoral-level…

  5. From Unity to Diversity... to Diversity within Unity

    ERIC Educational Resources Information Center

    Larsen-Freeman, Diane

    2012-01-01

    For the 25th anniversary issue of "English Teaching Forum," published in 1987, the author wrote about the diversification of the language teaching field. Her point then was that during the preceding years from 1962 to 1987, the language teaching field had diversified: Where earlier there had been a unified approach to language teaching, by 1987,…

  6. Getting Geology Students Into the Field

    NASA Astrophysics Data System (ADS)

    Nocerino, J.

    2011-12-01

    The importance of field schools to practicing geologists is unquestionable; yet, the opportunities to experience field geology are dwindling. The Geological Society of America (GSA), in cooperation with ExxonMobil, are currently offering three programs to support and encourage field geology. The GSA/ExxonMobil Bighorn Basin Field award is a field seminar in the Bighorn Basin of north-central Wyoming emphasizing multi-disciplinary integrated basin analysis. The GSA/ExxonMobil Field Camp Scholar Award provides undergraduate students 2,000 each to attend the field camp of their choice based on diversity, economic/financial need, and merit. Finally, the GSA/ExxonMobil Field Camp Excellence Award provides one geologic field camp leader an award of 10,000 to assist with their summer field camp season based on safety awareness, diversity, and technical excellence. This non-profit/industry collaboration has proven very successful and in 2011 over 300 geology students and professors have applied for these awards.

  7. Increased Risk of Insect Injury to Corn Following Rye Cover Crop.

    PubMed

    Dunbar, Mike W; O'Neal, Matthew E; Gassmann, Aaron J

    2016-08-01

    Decreased pest pressure is sometimes associated with more diverse agroecosystems, including the addition of a rye cover crop (Secale cereale L.). However, not all pests respond similarly to greater vegetational diversity. Polyphagous pests, such as true armyworm (Mythimna unipuncta Haworth), black cutworm (Agrotis ipsilon Hufnagel), and common stalk borer (Papaipema nebris Guenee), whose host range includes rye have the potential to cause injury to crops following a rye cover crop. The objectives of this study were to compare the abundance of early-season insect pests and injury to corn (Zea mays L.) from fields with and without a rye cover crop on commercial farms. Fields were sampled weekly to quantify adult and larval pests and feeding injury to corn plants from mid-April until corn reached V8 stage, during 2014 and 2015. Measurements within fields were collected along transects that extended perpendicularly from field edges into the interior of cornfields. Adult true armyworm and adult black cutworm were captured around all cornfields, but most lepidopteran larvae captured within cornfields were true armyworm and common stalk borer. Cornfields with a rye cover crop had significantly greater abundance of true armyworm and greater proportion of injured corn. Both true armyworm abundance and feeding injury were significantly greater in the interior of cornfields with rye. Common stalk borer abundance did not differ between cornfields with or without rye cover. Farmers planting corn following a rye cover crop should be aware of the potential for increased presence of true armyworm and for greater injury to corn. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Longitudinal prevalence and molecular typing of Escherichia coli O157:H7 by use of multiple-locus variable-number tandem-repeat analysis and pulsed-field gel electrophoresis in fecal samples collected from a range-based herd of beef cattle in California.

    PubMed

    Kondo, Sonoko; Hoar, Bruce R; Villanueva, Veronica; Mandrell, Robert E; Atwill, Edward R

    2010-11-01

    To evaluate seasonal patterns and risk factors for Escherichia coli O157:H7 in feces in a beef cattle herd and determine strain diversity and transition in E coli over time by use of multiple-locus variable-number tandem-repeat analysis (MLVA) and pulsed-field gel electrophoresis (PFGE). 456 samples of freshly passed feces collected over a 1-year period from cattle in a range-based cow-calf operation located in the foothills of the Sierra Nevada Mountains in California. E coli O157:H7 was recovered from feces by use of immunomagnetic separation and 2 selective media. Virulence factors were detected via reverse transcriptase-PCR assay. Escherichia coli O157:H7 isolates were subtyped with MLVA and PFGE. Prevalence estimates were calculated and significant risk factors determined. A dendrogram was constructed on the basis of results of MLVA typing. Overall prevalence estimate for E coli O157:H7 was 10.5%, with the prevalence lowest during the winter. Mean temperature during the 30 days before collection of samples was significantly associated with prevalence of E coli O157:H7 in feces. Nineteen MLVA and 12 PFGE types were identified. A seasonal pattern was detected for prevalence of E coli O157:H7 in feces collected from beef cattle in California. Subtyping via MLVA and PFGE revealed a diversity of E coli O157:H7 strains in a cow-calf operation and noteworthy turnover of predominant types. Given the importance of accurately determining sources of contamination in investigations of disease outbreaks in humans, MLVA combined with PFGE should be powerful tools for epidemiologists.

  9. Don't Wag the Dog: Extending the Reach of Applied Behavior Analysis

    PubMed Central

    Normand, Matthew P.; Kohn, Carolynn S.

    2013-01-01

    We argue that the field of behavior analysis would be best served if behavior analysts worked to extend the reach of behavioral services into a more diverse range of settings and with more varied populations, with an emphasis on the establishment of new career opportunities for graduating students. This is not a new proposal, but it is a tall order; it is not difficult to see why many would choose a surer route to gainful employment. Currently, the most fruitful career path for behavior analysts in practice is in the area of autism and developmental disabilities. For the continued growth of the field of behavior analysis, however, it is important to foster new career opportunities for those trained as behavior analysts. Toward this end, we identify several fields that seem well suited to behavior analysts and summarize the training requirements and likely professional outcomes for behavior analysts who pursue education and certification in these fields. These fields require relatively little additional formal training in the hopes of minimizing the response effort necessary for individuals who have already completed a rigorous program of graduate study in behavior analysis. PMID:25729134

  10. Natural Nanoparticles: A Particular Matter Inspired by Nature.

    PubMed

    Griffin, Sharoon; Masood, Muhammad Irfan; Nasim, Muhammad Jawad; Sarfraz, Muhammad; Ebokaiwe, Azubuike Peter; Schäfer, Karl-Herbert; Keck, Cornelia M; Jacob, Claus

    2017-12-29

    During the last couple of decades, the rapidly advancing field of nanotechnology has produced a wide palette of nanomaterials, most of which are considered as "synthetic" and, among the wider public, are often met with a certain suspicion. Despite the technological sophistication behind many of these materials, "nano" does not always equate with "artificial". Indeed, nature itself is an excellent nanotechnologist. It provides us with a range of fine particles, from inorganic ash, soot, sulfur and mineral particles found in the air or in wells, to sulfur and selenium nanoparticles produced by many bacteria and yeasts. These nanomaterials are entirely natural, and, not surprisingly, there is a growing interest in the development of natural nanoproducts, for instance in the emerging fields of phyto- and phyco-nanotechnology. This review will highlight some of the most recent-and sometimes unexpected-advances in this exciting and diverse field of research and development. Naturally occurring nanomaterials, artificially produced nanomaterials of natural products as well as naturally occurring or produced nanomaterials of natural products all show their own, particular chemical and physical properties, biological activities and promise for applications, especially in the fields of medicine, nutrition, cosmetics and agriculture. In the future, such natural nanoparticles will not only stimulate research and add a greener outlook to a traditionally high-tech field, they will also provide solutions-pardon-suspensions for a range of problems. Here, we may anticipate specific biogenic factories, valuable new materials based on waste, the effective removal of contaminants as part of nano-bioremediation, and the conversion of poorly soluble substances and materials to biologically available forms for practical uses.

  11. High spatial variation in population size and symbiotic performance of Rhizobium leguminosarum bv. trifolii with white clover in New Zealand pasture soils.

    PubMed

    Wakelin, Steven; Tillard, Guyléne; van Ham, Robert; Ballard, Ross; Farquharson, Elizabeth; Gerard, Emily; Geurts, Rene; Brown, Matthew; Ridgway, Hayley; O'Callaghan, Maureen

    2018-01-01

    Biological nitrogen fixation through the legume-rhizobia symbiosis is important for sustainable pastoral production. In New Zealand, the most widespread and valuable symbiosis occurs between white clover (Trifolium repens L.) and Rhizobium leguminosarum bv. trifolii (Rlt). As variation in the population size (determined by most probable number assays; MPN) and effectiveness of N-fixation (symbiotic potential; SP) of Rlt in soils may affect white clover performance, the extent in variation in these properties was examined at three different spatial scales: (1) From 26 sites across New Zealand, (2) at farm-wide scale, and (3) within single fields. Overall, Rlt populations ranged from 95 to >1 x 108 per g soil, with variation similar at the three spatial scales assessed. For almost all samples, there was no relationship between rhizobia population size and ability of the population to fix N during legume symbiosis (SP). When compared with the commercial inoculant strain, the SP of soils ranged between 14 to 143% efficacy. The N-fixing ability of rhizobia populations varied more between samples collected from within a single hill country field (0.8 ha) than between 26 samples collected from diverse locations across New Zealand. Correlations between SP and calcium and aluminium content were found in all sites, except within a dairy farm field. Given the general lack of association between SP and MPN, and high spatial variability of SP at single field scale, provision of advice for treating legume seed with rhizobia based on field-average MPN counts needs to be carefully considered.

  12. High spatial variation in population size and symbiotic performance of Rhizobium leguminosarum bv. trifolii with white clover in New Zealand pasture soils

    PubMed Central

    Tillard, Guyléne; van Ham, Robert; Ballard, Ross; Farquharson, Elizabeth; Gerard, Emily; Geurts, Rene; Brown, Matthew; Ridgway, Hayley; O’Callaghan, Maureen

    2018-01-01

    Biological nitrogen fixation through the legume-rhizobia symbiosis is important for sustainable pastoral production. In New Zealand, the most widespread and valuable symbiosis occurs between white clover (Trifolium repens L.) and Rhizobium leguminosarum bv. trifolii (Rlt). As variation in the population size (determined by most probable number assays; MPN) and effectiveness of N-fixation (symbiotic potential; SP) of Rlt in soils may affect white clover performance, the extent in variation in these properties was examined at three different spatial scales: (1) From 26 sites across New Zealand, (2) at farm-wide scale, and (3) within single fields. Overall, Rlt populations ranged from 95 to >1 x 108 per g soil, with variation similar at the three spatial scales assessed. For almost all samples, there was no relationship between rhizobia population size and ability of the population to fix N during legume symbiosis (SP). When compared with the commercial inoculant strain, the SP of soils ranged between 14 to 143% efficacy. The N-fixing ability of rhizobia populations varied more between samples collected from within a single hill country field (0.8 ha) than between 26 samples collected from diverse locations across New Zealand. Correlations between SP and calcium and aluminium content were found in all sites, except within a dairy farm field. Given the general lack of association between SP and MPN, and high spatial variability of SP at single field scale, provision of advice for treating legume seed with rhizobia based on field-average MPN counts needs to be carefully considered. PMID:29489845

  13. Applications of biological pores in nanomedicine, sensing, and nanoelectronics

    PubMed Central

    Majd, Sheereen; Yusko, Erik C; Billeh, Yazan N; Macrae, Michael X; Yang, Jerry; Mayer, Michael

    2011-01-01

    Biological protein pores and pore-forming peptides can generate a pathway for the flux of ions and other charged or polar molecules across cellular membranes. In nature, these nanopores have diverse and essential functions that range from maintaining cell homeostasis and participating in cell signaling to activating or killing cells. The combination of the nanoscale dimensions and sophisticated – often regulated – functionality of these biological pores make them particularly attractive for the growing field of nanobiotechnology. Applications range from single-molecule sensing to drug delivery and targeted killing of malignant cells. Potential future applications may include the use of nanopores for single strand DNA sequencing and for generating bio-inspired, and possibly, biocompatible visual detection systems and batteries. This article reviews the current state of applications of pore-forming peptides and proteins in nanomedicine, sensing, and nanoelectronics. PMID:20561776

  14. Jesuit scientific activity in the overseas missions, 1540-1773.

    PubMed

    Harris, Steven J

    2005-03-01

    Within the context of national traditions in colonial science, the scientific activities of Jesuit missionaries present us with a unique combination of challenges. The multinational membership of the Society of Jesus gave its missionaries access to virtually every Portuguese, Spanish, and French colony. The Society was thus compelled to engage an astonishingly diverse array of cultural and natural environments, and that diversity of contexts is reflected in the range and the complexity of Jesuit scientific practices. Underlying that complexity, however, was what I see as a unique combination of institutional structures; namely, European colleges, overseas mission stations, and the regular circulation of personnel and information. With this institutional framework as a backdrop, I briefly trace what I see as the most salient themes emerging from recent studies of Jesuit overseas science: (1) the Societys ability to use scientific expertise to its advantage amid the complex web of dependencies upon which it missionary activities rested; (2) the ability of its missionaries to become intimate with a wide range of cultures and to appropriate natural knowledge held by indigenous peoples, especially in the fields of material medica and geography; and (3) the different ways Jesuits used published accounts of "remote nature" (i.e., natural histories of overseas colonies) to advance their corporate and religious causes.

  15. High but not dry: diverse epiphytic bromeliad adaptations to exposure within a seasonally dry tropical forest community.

    PubMed

    Reyes-García, C; Mejia-Chang, M; Griffiths, H

    2012-02-01

    • Vascular epiphytes have developed distinct lifeforms to maximize water uptake and storage, particularly when delivered as pulses of precipitation, dewfall or fog. The seasonally dry forest of Chamela, Mexico, has a community of epiphytic bromeliads with Crassulacean acid metabolism showing diverse morphologies and stratification within the canopy. We hypothesize that niche differentiation may be related to the capacity to use fog and dew effectively to perform photosynthesis and to maintain water status. • Four Tillandsia species with either 'tank' or 'atmospheric' lifeforms were studied using seasonal field data and glasshouse experimentation, and compared on the basis of water use, leaf water δ(18) O, photosynthetic and morphological traits. • The atmospheric species, Tillandsia eistetteri, with narrow leaves and the lowest succulence, was restricted to the upper canopy, but displayed the widest range of physiological responses to pulses of precipitation and fog, and was a fog-catching 'nebulophyte'. The other atmospheric species, Tillandsia intermedia, was highly succulent, restricted to the lower canopy and with a narrower range of physiological responses. Both upper canopy tank species relied on tank water and stomatal closure to avoid desiccation. • Niche differentiation was related to capacity for water storage, dependence on fog or dewfall and physiological plasticity. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

  16. Latin America: A Development Pole for Phenomics

    PubMed Central

    Camargo, Anyela V.; Lobos, Gustavo A.

    2016-01-01

    Latin America and the Caribbean (LAC) has long been associated with the production and export of a diverse range of agricultural commodities. Due to its strategic geographic location, which encompasses a wide range of climates, it is possible to produce almost any crop. The climate diversity in LAC is a major factor in its agricultural potential but this also means climate change represents a real threat to the region. Therefore, LAC farming must prepare and quickly adapt to an environment that is likely to feature long periods of drought, excessive rainfall and extreme temperatures. With the aim of moving toward a more resilient agriculture, LAC scientists have created the Latin American Plant Phenomics Network (LatPPN) which focuses on LAC's economically important crops. LatPPN's key strategies to achieve its main goal are: (1) training of LAC members on plant phenomics and phenotyping, (2) establish international and multidisciplinary collaborations, (3) develop standards for data exchange and research protocols, (4) share equipment and infrastructure, (5) disseminate data and research results, (6) identify funding opportunities and (7) develop strategies to guarantee LatPPN's relevance and sustainability across time. Despite the challenges ahead, LatPPN represents a big step forward toward the consolidation of a common mind-set in the field of plant phenotyping and phenomics in LAC. PMID:27999577

  17. Latin America: A Development Pole for Phenomics.

    PubMed

    Camargo, Anyela V; Lobos, Gustavo A

    2016-01-01

    Latin America and the Caribbean (LAC) has long been associated with the production and export of a diverse range of agricultural commodities. Due to its strategic geographic location, which encompasses a wide range of climates, it is possible to produce almost any crop. The climate diversity in LAC is a major factor in its agricultural potential but this also means climate change represents a real threat to the region. Therefore, LAC farming must prepare and quickly adapt to an environment that is likely to feature long periods of drought, excessive rainfall and extreme temperatures. With the aim of moving toward a more resilient agriculture, LAC scientists have created the Latin American Plant Phenomics Network (LatPPN) which focuses on LAC's economically important crops. LatPPN's key strategies to achieve its main goal are: (1) training of LAC members on plant phenomics and phenotyping, (2) establish international and multidisciplinary collaborations, (3) develop standards for data exchange and research protocols, (4) share equipment and infrastructure, (5) disseminate data and research results, (6) identify funding opportunities and (7) develop strategies to guarantee LatPPN's relevance and sustainability across time. Despite the challenges ahead, LatPPN represents a big step forward toward the consolidation of a common mind-set in the field of plant phenotyping and phenomics in LAC.

  18. Genome surfing as driver of microbial genomic diversity

    USDA-ARS?s Scientific Manuscript database

    Historical changes in population size, such as those caused by demographic range expansions, can produce nonadaptive changes in genomic diversity through mechanisms such as gene surfing. We propose that demographic range expansion of a microbial population capable of horizontal gene exchange can res...

  19. Yardangs in the Qaidam Basin, northwestern China: Distribution and morphology

    NASA Astrophysics Data System (ADS)

    Li, Jiyan; Dong, Zhibao; Qian, Guangqiang; Zhang, Zhengcai; Luo, Wanyin; Lu, Junfeng; Wang, Meng

    2016-03-01

    The northwestern Qaidam Basin exposes one of the largest and highest elevation yardang fields on Earth. The aim of the present study was to describe the distribution and morphology of these yardangs, and analyze the factors responsible for the distribution pattern of these aeolian landforms. The yardang fields are bounded by piedmont alluvial-diluvial fans from the mountain ranges surrounding the basin, except in the south, where they are bounded by dune fields, dry salt flats, lakes, and rivers. This distribution pattern can be attributed to regional tectogenesis and its corresponding environmental impacts. The morphology of the yardangs varies considerably in response to the diverse factors that control their formation and evolution. Long-ridge yardangs are mainly located in the northernmost part of the yardang field, and the long ridges are gradually dissected into smaller ridges in the downwind direction. Further downwind, the convergence of northerly and northwesterly winds and the effects of temporary runoff cause the ridges to gradually transition into mesa yardangs. Saw-toothed crests, and conical and pyramidal yardangs, occur in groups on folded brachyanticlinal structures. Typical whaleback yardangs are found in the southeast, at the northern margin of Dabuxun Lake. Morphological parameters vary among the yardang types. The orientation of the yardangs in the northernmost area is nearly N-S, with a transition towards NW-SE in the southernmost area in response to a change in the dominant wind direction that results from the orientations and positions of the mountain ranges that surround the basin.

  20. Mapping the spatial distribution of star formation in cluster galaxies at z ~ 0.5 with the Grism Lens-Amplified Survey from Space (GLASS)

    NASA Astrophysics Data System (ADS)

    Vulcani, Benedetta; Vulcani

    We present the first study of the spatial distribution of star formation in z ~ 0.5 cluster galaxies. The analysis is based on data taken with the Wide Field Camera 3 as part of the Grism Lens-Amplified Survey from Space (GLASS). We illustrate the methodology by focusing on two clusters (MACS0717.5+3745 and MACS1423.8+2404) with different morphologies (one relaxed and one merging) and use foreground and background galaxies as field control sample. The cluster+field sample consists of 42 galaxies with stellar masses in the range 108-1011 M ⊙, and star formation rates in the range 1-20 M⊙ yr -1. In both environments, Hα is more extended than the rest-frame UV continuum in 60% of the cases, consistent with diffuse star formation and inside out growth. The Hα emission appears more extended in cluster galaxies than in the field, pointing perhaps to ionized gas being stripped and/or star formation being enhanced at large radii. The peak of the Hα emission and that of the continuum are offset by less than 1 kpc. We investigate trends with the hot gas density as traced by the X-ray emission, and with the surface mass density as inferred from gravitational lens models and find no conclusive results. The diversity of morphologies and sizes observed in Hα illustrates the complexity of the environmental process that regulate star formation.

  1. Successive range expansion promotes diversity and accelerates evolution in spatially structured microbial populations.

    PubMed

    Goldschmidt, Felix; Regoes, Roland R; Johnson, David R

    2017-09-01

    Successive range expansions occur within all domains of life, where one population expands first (primary expansion) and one or more secondary populations then follow (secondary expansion). In general, genetic drift reduces diversity during range expansion. However, it is not clear whether the same effect applies during successive range expansion, mainly because the secondary population must expand into space occupied by the primary population. Here we used an experimental microbial model system to show that, in contrast to primary range expansion, successive range expansion promotes local population diversity. Because of mechanical constraints imposed by the presence of the primary population, the secondary population forms fractal-like dendritic structures. This divides the advancing secondary population into many small sub-populations and promotes intermixing between the primary and secondary populations. We further developed a mathematical model to simulate the formation of dendritic structures in the secondary population during succession. By introducing mutations in the primary or dendritic secondary populations, we found that mutations are more likely to accumulate in the dendritic secondary populations. Our results thus show that successive range expansion can promote intermixing over the short term and increase genetic diversity over the long term. Our results therefore have potentially important implications for predicting the ecological processes and evolutionary trajectories of microbial communities.

  2. No correlation between the diversity and productivity of assemblages: evidence from the phytophage and predator assemblages in various cotton agroecosystems.

    PubMed

    Gao, Feng; Men, XingYuan; Ge, Feng

    2014-09-01

    Biodiversity research has shown that primary productivity increases with plant species number, especially in many experimental grassland systems. Here, we assessed the correlation between productivity and diversity of phytophages and natural enemy assemblages associated with planting date and intercropping in four cotton agroecosystems. Twenty-one pairs of data were used to determine Pearson correlations between species richness, total number of individuals, diversity indices and productivity for each assemblage every five days from 5 June to 15 September 2012. At the same trophic level, the productivity exhibited a significant positive correlation with species richness of the phytophage or predator assemblage. A significant correlation was found between productivity and total number of individuals in most cotton fields. However, no significant correlations were observed between productivity and diversity indices (including indices of energy flow diversity and numerical diversity) in most cotton fields for either the phytophage or the predator assemblages. Species richness of phytophage assemblage and total individual numbers were significantly correlated with primary productivity. Also, species richness of natural enemy assemblage and total number of individuals correlated with phytophage assemblage productivity. A negative but not significant correlation occurred between the indices of numerical diversity and energy flow diversity and lower trophic-level productivity in the cotton-phytophage and phytophage-predator assemblages for most intercropped cotton agroecosystems. Our results clearly showed that there were no correlations between diversity indices and productivity within the same or lower trophic levels within the phytophage and predator assemblages in cotton agroecosystems, and inter-cropped cotton fields had a stronger ability to support the natural enemy assemblage and potentially to reduce phytophages.

  3. The wild flora biodiversity in pesticide free bufferzones along old hedgerows.

    PubMed

    Andresen, L C; Nothlev, J; Kristensen, K; Navntoft, S; Johnsen, I

    2012-05-01

    The natural field margin ecotone from the field border and into a cropped field hosts a diversity of plant species. In conventional cropped fields, biodiversity suffers from fertilizer and pesticide application. In our study at Danish conventional spring-barley fields, we laid out bufferzones with no pesticide application spraying after sowing, with the widths: 24, 12, 6 and 4 m (and control) to the field edge hedgerow. Through one season: plant species number, biodiversity and evenness for each bufferzone at the distances: 18, 9, 5, 2 and 0 m from the hedgerow were significantly affected by distance to the hedge and by width of bufferzone. The bufferzones affected: species number (total of 92 weed species), species diversity (1.27 to 0.44) and species evenness index (0.63 to 0.87), and revealed that the bufferzone of 24 m gave the largest improvementof the field margin for plants. Decreasing the bufferzone widths provided smaller biodiversity and larger evenness of plants at distances larger than the buffer width: the distance at which diversity (Shannons) was reduced by half the difference between hedge- and field diversity was 1.2, 3.1, 6.7, 10.8 and 10.9 m in bufferwidth treatments of 0, 4, 6, 12 and 24 m; likewise, the half-way distance for Smiths and Wilsons evenness index was 1.2, 1.7, 5.4, 14.0 and 30.2 m in the bufferwidth treatments of 0, 4, 6,12 and 24 m. Based on modelled diversity and evenness indexes a positive effect of buffer was evident from 6 m bufferzone. The average diversity over the distances from 0 to 18 m was 0.66, 0.75, 0.98, 1.14 and 1.11 in bufferwidth treatments of 0, 4, 6, 12 and 24 m and the average evenness over the distances from 0 to 18 m was 0.82, 0.80, 0.74, 0.66 and 0.63, in bufferwidth treatments of 0, 4, 6, 12 and 24 m. Furthermore, the accumulated number of species revealed that a bufferzone width of at least 6 m was needed to significantly increase the species richness at all distances between 2 and 18 m. At 18 m distance, the accumulated number of species was 37.1, 39.7, 41.2, 42.4 and 42.7 in bufferwidth treatments of 0, 4, 6, 12 and 24 m.

  4. A current disruption mechanism in the neutral sheet for triggering substorm expansions

    NASA Technical Reports Server (NTRS)

    Lui, A. T. Y.; Mankofsky, A.; Chang, C.-L.; Papadopoulos, K.; Wu, C. S.

    1989-01-01

    Two main areas were addressed in support of an effort to understand mechanism responsible for the broadband electrostatic noise (BEN) observed in the magnetotail. The first area concerns the generation of BEN in the boundary layer region of the magnetotail whereas the second area concerns the occassional presence of BEN in the neutral sheet region. For the generation of BEN in the boundary layer region, a hybrid simulation code was developed to perform reliable longtime, quiet, highly resolved simulations of field aligned electron and ion beam flow. The result of the simulation shows that broadband emissions cannot be generated by beam-plasma instability if realistic values of the ion beam parameters are used. The waves generated from beam-plasma instability are highly discrete and are of high frequencies. For the plasma sheet boundary layer condition, the wave frequencies are in the kHz range, which is incompatible with the observation that the peak power in BEN occur in the 10's of Hz range. It was found that the BEN characteristics are more consistent with lower hybrid drift instability. For the occasional presence of BEN in the neutral sheet region, a linear analysis of the kinetic cross-field streaming instability appropriate to the neutral sheet condition just prior to onset of substorm expansion was performed. By solving numerically the dispersion relation, it was found that the instability has a growth time comparable to the onset time scale of substorm onset. The excited waves have a mixed polarization in the lower hybrid frequency range. The imposed drift driving the instability corresponds to unmagnetized ions undergoing current sheet acceleration in the presence of a cross-tail electric field. The required electric field strength is in the 10 mV/m range which is well within the observed electric field values detected in the neutral sheet during substorms. This finding can potentially account for the disruption of cross-tail current and its diversion to the ionosphere to form the substorm current wedge. Furthermore, a number of features associated with substorm expansion onset can be understood based on this substorm onset scenario.

  5. Aspergillus flavus genetic diversity of corn fields treated with non-toxigenic strain afla-guard in the southern U.S

    USDA-ARS?s Scientific Manuscript database

    Aspergillus flavus genetic diversity of corn fields treated with the non-toxigenic strain Afla-Guard (NRRL 21882) was determined for 384 A. flavus isolates from 14 locations within 6 states in the southern U.S. ELISA test has determined low levels of toxigenic strains (only 91 positive). Nearly hal...

  6. Efforts in Increasing Racial and Ethnic Diversity in the Field of Art Therapy

    ERIC Educational Resources Information Center

    Awais, Yasmine J.; Yali, Ann Marie

    2015-01-01

    There is a clear need for greater diversity in the field of art therapy, with a particular need to increase the representation of racial and ethnic minorities in educational programs. In a sample of 16 art therapy program directors, strategies and barriers to recruitment were identified through an anonymous online survey. The results of the survey…

  7. Voices for Diversity.

    ERIC Educational Resources Information Center

    Future Teacher, 1995

    1995-01-01

    Prominent Americans were asked to reflect on the diversity challenge facing America's teacher workforce. The following leaders from several fields voiced their support of teachers and their beliefs America needs more diverse and culturally responsive teachers: (1) Mary Hatwood Futrell, President of Education International; (2) Carol Moseley-Braun,…

  8. Antimicrobial Properties of Plant Essential Oils against Human Pathogens and Their Mode of Action: An Updated Review

    PubMed Central

    2016-01-01

    A wide range of medicinal and aromatic plants (MAPs) have been explored for their essential oils in the past few decades. Essential oils are complex volatile compounds, synthesized naturally in different plant parts during the process of secondary metabolism. Essential oils have great potential in the field of biomedicine as they effectively destroy several bacterial, fungal, and viral pathogens. The presence of different types of aldehydes, phenolics, terpenes, and other antimicrobial compounds means that the essential oils are effective against a diverse range of pathogens. The reactivity of essential oil depends upon the nature, composition, and orientation of its functional groups. The aim of this article is to review the antimicrobial potential of essential oils secreted from MAPs and their possible mechanisms of action against human pathogens. This comprehensive review will benefit researchers who wish to explore the potential of essential oils in the development of novel broad-spectrum key molecules against a broad range of drug-resistant pathogenic microbes. PMID:28090211

  9. The effects of diversity and network ties on innovations: The emergence of a new scientific field.

    PubMed

    Lungeanu, Alina; Contractor, Noshir S

    2015-05-01

    This study examines the influence of different types of diversity, both observable and unobservable, on the creation of innovative ideas. Our framework draws upon theory and research on information processing, social categorization, coordination, and homophily to posit the influence of cognitive, gender, and country diversity on innovation. Our longitudinal model is based on a unique dataset of 1,354 researchers who helped create the new scientific field of Oncofertility, by collaborating on 469 publications over a four-year period. We capture the differences among researchers along cognitive, country and gender dimensions, as well as examine how the resulting diversity or homophily influences the formation of collaborative innovation networks. We find that innovation, operationalized as publishing in a new scientific discipline, benefits from both homophily and diversity. Homophily in country of residence and working with prior collaborators help reduce uncertainty in the interactions associated with innovation, while diversity in knowledge enables the recombinant knowledge required for innovation.

  10. Nitrogen comes down to earth: report from the 5th European Nitrogen Fixation Conference.

    PubMed

    De Hoff, Peter; Hirsch, Ann M

    2003-05-01

    For four days and four nights, with almost 50 presentations and more than 175 posters, the 5th European Nitrogen Fixation Conference continued a tradition of excellence, bringing scientists from diverse fields such as microbiology, biochemistry, computational genomics, and plant physiology together to address the complex problems associated with biological nitrogen fixation (BNF). The conference was hosted by the John Innes Center and the University of East Anglia in Norwich, England and took place from September 6 through 10, 2002. A diverse range of topics was presented, from the evolution of rhizobial genomes to the plant genes involved in bacterial and fungal symbiosis, to the structure of nitrogenase, and to the means by which nitrogen is shuttled between the symbiotic bacteria and the plant. Additionally, sessions involving broader issues, such as nitrogen fertilizer use and work being done in developing countries, brought home the importance of the research being carried out in BNF around the world.

  11. Changes of arthropod diversity across an altitudinal ecoregional zonation in Northwestern Argentina

    PubMed Central

    González-Reyes, Andrea X.; Rodriguez-Artigas, Sandra M.

    2017-01-01

    This study examined arthropod community patterns over an altitudinal ecoregional zonation that extended through three ecoregions (Yungas, Monte de Sierras y Bolsones, and Puna) and two ecotones (Yungas-Monte and Prepuna) of Northwestern Argentina (altitudinal range of 2,500 m), and evaluated the abiotic and biotic factors and the geographical distance that could influence them. Pitfall trap and suction samples were taken seasonally in 15 sampling sites (1,500–4,000 m a.s.l) during one year. In addition to climatic variables, several soil and vegetation variables were measured in the field. Values obtained for species richness between ecoregions and ecotones and by sampling sites were compared statistically and by interpolation–extrapolation analysis based on individuals at the same sample coverage level. Effects of predictor variables and the similarity of arthropods were shown using non-metric multidimensional scaling, and the resulting groups were evaluated using a multi-response permutation procedure. Polynomial regression was used to evaluate the relationship between altitude with total species richness and those of hyperdiverse/abundant higher taxa and the latter taxa with each predictor variable. The species richness pattern displayed a decrease in species diversity as the elevation increased at the bottom wet part (Yungas) of our altitudinal zonation until the Monte, and a unimodal pattern of diversity in the top dry part (Monte, Puna). Each ecoregion and ecotonal zone evidenced a particular species richness and assemblage of arthropods, but the latter ones displayed a high percentage of species shared with the adjacent ecoregions. The arthropod elevational pattern and the changes of the assemblages were explained by the environmental gradient (especially the climate) in addition to a geographic gradient (the distance of decay of similarity), demonstrating that the species turnover is important to explain the beta diversity along the elevational gradient. This suggests that patterns of diversity and distribution of arthropods are regulated by the dissimilarity of ecoregional environments that establish a wide range of geographic and environmental barriers, coupled with a limitation of species dispersal. Therefore, the arthropods of higher taxa respond differently to the altitudinal ecoregional zonation. PMID:29230361

  12. Population genetics of the invasive cryptogenic anemone, Anemonia alicemartinae, along the southeastern Pacific coast

    NASA Astrophysics Data System (ADS)

    Canales-Aguirre, C. B.; Quiñones, A.; Hernández, C. E.; Neill, P. E.; Brante, A.

    2015-08-01

    One of the most important issues in biological invasions is understanding the factors and mechanisms determining the invasion success of non-native species. Theoretical and empirical works have shown that genetic diversity is a determinant of invasion success; thus, studying spatial patterns of genetic diversity, and exploring how biological and physical factors shape this population trait, are fundamental for understanding this phenomenon. Coastal marine ecosystems are one of the most susceptible habitats to invasion given the complex network of maritime transport. In this work we study the cryptogenic anemone, Anemonia alicemartinae, which has rapidly increased its geographical range southward during the last 50 years (approx. 2000 km) along the southeastern Pacific coast. Based on COI mtDNA sequences we evaluated three main hypotheses: a) the genetic diversity of A. alicemartinae decreases according to the direction of invasion (from north to south); b) there is biogeographic-phylogeographic concordance at the 30°S biogeographic break; and c) the demographic history is coherent with a recent geographic expansion. A total of 161 individual samples of A. alicemartinae were collected along the southeastern Pacific coast range of distribution, covering more than 2000 km, including samples along the 30°S biogeographical break. Results showed low genetic diversity (Hd = 0.253; π = 0.08) and a lack of geographic population genetic structure (FST = - 0.009, p-value = 0.656). The highest genetic diversity was observed in Peru (Chero and Mesas) and at localities close to the main Chilean seaports. We did not observe concordance between biogeographic and phylogeographic patterns or isolation by distance. Demographic indices (D = - 2.604, p < 0.001; Fu's = - 26.619, p < 0.001), as well as a star-like configuration of the haplotype network support recent population expansion of this species. Our results, together with historical field observations, support the idea that the current distribution of A. alicemartinae may be explained by an increase in population size from one small ancestral population probably from the south of Peru, with subsequent human-mediated southward transport, probably associated with regional-scale maritime activities.

  13. Evolution on the move: specialization on widespread resources associated with rapid range expansion in response to climate change.

    PubMed

    Bridle, Jon R; Buckley, James; Bodsworth, Edward J; Thomas, Chris D

    2014-02-07

    Generalist species and phenotypes are expected to perform best under rapid environmental change. In contrast to this view that generalists will inherit the Earth, we find that increased use of a single host plant is associated with the recent climate-driven range expansion of the UK brown argus butterfly. Field assays of female host plant preference across the UK reveal a diversity of adaptations to host plants in long-established parts of the range, whereas butterflies in recently colonized areas are more specialized, consistently preferring to lay eggs on one host plant species that is geographically widespread throughout the region of expansion, despite being locally rare. By common-garden rearing of females' offspring, we also show an increase in dispersal propensity associated with the colonization of new sites. Range expansion is therefore associated with an increase in the spatial scale of adaptation as dispersive specialists selectively spread into new regions. Major restructuring of patterns of local adaptation is likely to occur across many taxa with climate change, as lineages suited to regional colonization rather than local success emerge and expand.

  14. A Call for Diversity: The Need to Recruit and Retain Ethnic Minority Students in Art Therapy

    ERIC Educational Resources Information Center

    Awais, Yasmine J.; Yali, Ann Marie

    2013-01-01

    There is a clear need for greater diversity in the field of art therapy with particular attention to increasing the representation of students of color in art therapy training programs. However, little to no data exists on how art therapy programs are actively recruiting for diversity. Diversity in the classroom can offer novel perspectives on…

  15. Invited Article: Mask-modulated lensless imaging with multi-angle illuminations

    NASA Astrophysics Data System (ADS)

    Zhang, Zibang; Zhou, You; Jiang, Shaowei; Guo, Kaikai; Hoshino, Kazunori; Zhong, Jingang; Suo, Jinli; Dai, Qionghai; Zheng, Guoan

    2018-06-01

    The use of multiple diverse measurements can make lensless phase retrieval more robust. Conventional diversity functions include aperture diversity, wavelength diversity, translational diversity, and defocus diversity. Here we discuss a lensless imaging scheme that employs multiple spherical-wave illuminations from a light-emitting diode array as diversity functions. In this scheme, we place a binary mask between the sample and the detector for imposing support constraints for the phase retrieval process. This support constraint enforces the light field to be zero at certain locations and is similar to the aperture constraint in Fourier ptychographic microscopy. We use a self-calibration algorithm to correct the misalignment of the binary mask. The efficacy of the proposed scheme is first demonstrated by simulations where we evaluate the reconstruction quality using mean square error and structural similarity index. The scheme is then experimentally tested by recovering images of a resolution target and biological samples. The proposed scheme may provide new insights for developing compact and large field-of-view lensless imaging platforms. The use of the binary mask can also be combined with other diversity functions for better constraining the phase retrieval solution space. We provide the open-source implementation code for the broad research community.

  16. A NEW APPROACH TO IDENTIFYING THE MOST POWERFUL GRAVITATIONAL LENSING TELESCOPES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wong, Kenneth C.; Zabludoff, Ann I.; Ammons, S. Mark

    2013-05-20

    The best gravitational lenses for detecting distant galaxies are those with the largest mass concentrations and the most advantageous configurations of that mass along the line of sight. Our new method for finding such gravitational telescopes uses optical data to identify projected concentrations of luminous red galaxies (LRGs). LRGs are biased tracers of the underlying mass distribution, so lines of sight with the highest total luminosity in LRGs are likely to contain the largest total mass. We apply this selection technique to the Sloan Digital Sky Survey and identify the 200 fields with the highest total LRG luminosities projected withinmore » a 3.'5 radius over the redshift range 0.1 {<=} z {<=} 0.7. The redshift and angular distributions of LRGs in these fields trace the concentrations of non-LRG galaxies. These fields are diverse; 22.5% contain one known galaxy cluster and 56.0% contain multiple known clusters previously identified in the literature. Thus, our results confirm that these LRGs trace massive structures and that our selection technique identifies fields with large total masses. These fields contain two to three times higher total LRG luminosities than most known strong-lensing clusters and will be among the best gravitational lensing fields for the purpose of detecting the highest redshift galaxies.« less

  17. Bioinspired magnetoreception and navigation using magnetic signatures as waypoints.

    PubMed

    Taylor, Brian K

    2018-05-15

    Diverse taxa use Earth's magnetic field in conjunction with other sensory modalities to accomplish navigation tasks ranging from local homing to long-distance migration across continents and ocean basins. However, despite extensive research, the mechanisms that underlie animal magnetoreception are not clearly understood, and how animals use Earth's magnetic field to navigate is an active area of investigation. Concurrently, Earth's magnetic field offers a signal that engineered systems can leverage for navigation in environments where man-made systems such as GPS are unavailable or unreliable. Using a proxy for Earth's magnetic field, and inspired by migratory animal behavior, this work implements a behavioral strategy that uses combinations of magnetic field properties as rare or unique signatures that mark specific locations. Using a discrete number of these signatures as goal waypoints, the strategy navigates through a closed set of points several times in a variety of environmental conditions, and with various levels of sensor noise. The results from this engineering/quantitative biology approach support existing notions that some animals may use combinations of magnetic properties as navigational markers, and provides insights into features and constraints that would enable navigational success or failure. The findings also offer insights into how autonomous engineered platforms might be designed to leverage the magnetic field as a navigational resource.

  18. Workforce Diversity in Outpatient Substance Abuse Treatment: The Role of Leaders’ Characteristics

    PubMed Central

    Guerrero, Erick G.

    2012-01-01

    Although the outpatient substance abuse treatment field has seen an increase in referrals of African American and Latino clients, there have been limited changes in the diversity of the workforce. This discordance may exacerbate treatment disparities experienced by these clients. Program leaders have significant influence to leverage resources to develop staff diversity. Analysis of panel data from 1995 to 2005 showed that the most significant predictors of diversity were the characteristics of leaders. In particular, programs with managers with racially and ethnically concordant backgrounds and their education level were positively related to the percentage of Latino and African American staff. A high percentage of African American staff was positively associated with managers’ tenure, but inversely related to licensed directors. Diversification of the field has increased, yet efforts have not matched increases in client diversity. Implications for health care reform legislation seeking to improve cultural competence through diversification of the workforce are discussed. PMID:22658932

  19. Diversity Digest. Volume 9, Number 1

    ERIC Educational Resources Information Center

    Musil, Caryn McTighe, Ed.; Hovland, Kevin, Ed.

    2005-01-01

    Civic engagement is the focus of this issue of "Diversity Digest." Concrete examples of institutions that have linked diversity and civic engagement in powerful, effective, and educationally transforming ways are presented. What is seen in the field is encouraging. Articles feature new conceptual frameworks for civic learning, curricular…

  20. Diversity's Impact on the Executive Coaching Process

    ERIC Educational Resources Information Center

    Maltbia, Terrence E.; Power, Anne

    2005-01-01

    This paper presents a conceptual model intended to expand existing executive coaching processes used in organizations by building the strategic learning capabilities needed to integrate a diversity perspective into this emerging field of HRD practice. This model represents the early development of results from a Diversity Practitioner Study…

  1. Multiple introductions boosted genetic diversity in the invasive range of black cherry (Prunus serotina; Rosaceae)

    PubMed Central

    Pairon, Marie; Petitpierre, Blaise; Campbell, Michael; Guisan, Antoine; Broennimann, Olivier; Baret, Philippe V.; Jacquemart, Anne-Laure; Besnard, Guillaume

    2010-01-01

    Background and Aims Black cherry (Prunus serotina) is a North American tree that is rapidly invading European forests. This species was introduced first as an ornamental plant then it was massively planted by foresters in many countries but its origins and the process of invasion remain poorly documented. Based on a genetic survey of both native and invasive ranges, the invasion history of black cherry was investigated by identifying putative source populations and then assessing the importance of multiple introductions on the maintenance of gene diversity. Methods Genetic variability and structure of 23 populations from the invasive range and 22 populations from the native range were analysed using eight nuclear microsatellite loci and five chloroplast DNA regions. Key Results Chloroplast DNA diversity suggests there were multiple introductions from a single geographic region (the north-eastern United States). A low reduction of genetic diversity was observed in the invasive range for both nuclear and plastid genomes. High propagule pressure including both the size and number of introductions shaped the genetic structure in Europe and boosted genetic diversity. Populations from Denmark, The Netherlands, Belgium and Germany showed high genetic diversity and low differentiation among populations, supporting the hypothesis that numerous introduction events, including multiple individuals and exchanges between sites, have taken place during two centuries of plantation. Conclusions This study postulates that the invasive black cherry has originated from east of the Appalachian Mountains (mainly the Allegheny plateau) and its invasiveness in north-western Europe is mainly due to multiple introductions containing high numbers of individuals. PMID:20400456

  2. Complex Light

    NASA Astrophysics Data System (ADS)

    Secor, Jeff; Alfano, Robert; Ashrafi, Solyman

    2017-01-01

    The emerging field of complex light-the study and application of custom light beams with tailored intensity, polarization or phase-is a focal point for fundamental breakthroughs in optical science. As this review will show, those advances in fundamental understanding, coupled with the latest developments in complex light generation, are translating into a range of diverse and cross-disciplinary applications that span microscopy, high-data-rate communications, optical trapping and quantum optics. We can expect more twists along the way, too, as researchers seek to manipulate and control the propagation speed of complex light beams, while others push the more exotic possibilities afforded by complex light in quantum-entanglement experiments.

  3. Fractography of induction-hardened steel fractured in fatigue and overload

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Santos, C.G.; Laird, C.

    1997-07-01

    The fracture surfaces of induction-hardened steel specimens obtained from an auto axle were characterized, macroscopically and microscopically, after being fractured in fatigue and monotonic overload. Specimens were tested in cyclic three-point bending under load control, and the S-N curve was established for specimens that had been notched by spark machining to facilitate fractography. Scanning electron microscopy of the fractured surfaces obtained for lives spanning the range 17,000 to 418,000 cycles revealed diverse fracture morphologies, including intergranular fracture and transgranular fatigue fracture. The results are being offered to assist in the analysis of complex field failures in strongly hardened steel.

  4. Wavefront Sensing with the Fine Guidance Sensor for James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    Smith, J. Scott; Aronstein, David; Dean, Bruce H.; Howard,Joe; Shiri, Ron

    2008-01-01

    An analysis is presented that utilizes the Fine Guidance Sensor (FGS) for focal-plane wavefront sensing (WFS) for the James Webb Space Telescope (JWST). WFS with FGS increases the number of wavefront measurements taken in field of the telescope, but has many challenges over the other JWST instruments that make it unique, such as; less sampling of the Point Spread Function (PSF), a smaller diversity-defocus range, a smaller image detector size, and a polychromatic object or source. Additionally, presented is an analysis of sampling for wavefront sensing. Results are shown based on simulations of flight and the cryogenic optical testing at NASA Johnson Space Center.

  5. Capturing the Diversity in Lexical Diversity

    ERIC Educational Resources Information Center

    Jarvis, Scott

    2013-01-01

    The range, variety, or diversity of words found in learners' language use is believed to reflect the complexity of their vocabulary knowledge as well as the level of their language proficiency. Many indices of lexical diversity have been proposed, most of which involve statistical relationships between types and tokens, and which ultimately…

  6. Faculty Teaching Diversity through Difficult Dialogues: Stories of Challenges and Success

    ERIC Educational Resources Information Center

    Gayles, Joy Gaston; Kelly, Bridget Turner; Grays, Shaefny; Zhang, Jing Jing; Porter, Kamaria P.

    2015-01-01

    Teaching diversity courses in graduate preparation programs is likely to trigger difficult dialogues that evoke a range of emotional responses. Difficult dialogues on diversity topics must be managed effectively in order to enhance multicultural competence. This interpretive study examined the experiences of faculty who teach diversity courses in…

  7. Opto-thermoelectric nanotweezers

    NASA Astrophysics Data System (ADS)

    Lin, Linhan; Wang, Mingsong; Peng, Xiaolei; Lissek, Emanuel N.; Mao, Zhangming; Scarabelli, Leonardo; Adkins, Emily; Coskun, Sahin; Unalan, Husnu Emrah; Korgel, Brian A.; Liz-Marzán, Luis M.; Florin, Ernst-Ludwig; Zheng, Yuebing

    2018-04-01

    Optical manipulation of plasmonic nanoparticles provides opportunities for fundamental and technical innovation in nanophotonics. Optical heating arising from the photon-to-phonon conversion is considered as an intrinsic loss in metal nanoparticles, which limits their applications. We show here that this drawback can be turned into an advantage, by developing an extremely low-power optical tweezing technique, termed opto-thermoelectric nanotweezers. By optically heating a thermoplasmonic substrate, a light-directed thermoelectric field can be generated due to spatial separation of dissolved ions within the heating laser spot, which allows us to manipulate metal nanoparticles of a wide range of materials, sizes and shapes with single-particle resolution. In combination with dark-field optical imaging, nanoparticles can be selectively trapped and their spectroscopic response can be resolved in situ. With its simple optics, versatile low-power operation, applicability to diverse nanoparticles and tunable working wavelength, opto-thermoelectric nanotweezers will become a powerful tool in colloid science and nanotechnology.

  8. Opto-thermoelectric nanotweezers.

    PubMed

    Lin, Linhan; Wang, Mingsong; Peng, Xiaolei; Lissek, Emanuel N; Mao, Zhangming; Scarabelli, Leonardo; Adkins, Emily; Coskun, Sahin; Unalan, Husnu Emrah; Korgel, Brian A; Liz-Marzán, Luis M; Florin, Ernst-Ludwig; Zheng, Yuebing

    2018-04-01

    Optical manipulation of plasmonic nanoparticles provides opportunities for fundamental and technical innovation in nanophotonics. Optical heating arising from the photon-to-phonon conversion is considered as an intrinsic loss in metal nanoparticles, which limits their applications. We show here that this drawback can be turned into an advantage, by developing an extremely low-power optical tweezing technique, termed opto-thermoelectric nanotweezers (OTENT). Through optically heating a thermoplasmonic substrate, alight-directed thermoelectric field can be generated due to spatial separation of dissolved ions within the heating laser spot, which allows us to manipulate metal nanoparticles of a wide range of materials, sizes and shapes with single-particle resolution. In combination with dark-field optical imaging, nanoparticles can be selectively trapped and their spectroscopic response can be resolved in-situ . With its simple optics, versatile low-power operation, applicability to diverse nanoparticles, and tuneable working wavelength, OTENT will become a powerful tool in colloid science and nanotechnology.

  9. Interpretation of coagulation test results using a web-based reporting system.

    PubMed

    Quesada, Andres E; Jabcuga, Christine E; Nguyen, Alex; Wahed, Amer; Nedelcu, Elena; Nguyen, Andy N D

    2014-01-01

    Web-based synoptic reporting has been successfully integrated into diverse fields of pathology, improving efficiency and reducing typographic errors. Coagulation is a challenging field for practicing pathologists and pathologists-in-training alike. To develop a Web-based program that can expedite the generation of a individualized interpretive report for a variety of coagulation tests. We developed a Web-based synoptic reporting system composed of 119 coagulation report templates and 38 thromboelastography (TEG) report templates covering a wide range of findings. Our institution implemented this reporting system in July 2011; it is currently used by pathology residents and attending pathologists. Feedback from the users of these reports have been overwhelmingly positive. Surveys note the time saved and reduced errors. Our easily accessible, user-friendly, Web-based synoptic reporting system for coagulation is a valuable asset to our laboratory services. Copyright© by the American Society for Clinical Pathology (ASCP).

  10. Evolutionary anthropology and genes: investigating the genetics of human evolution from excavated skeletal remains.

    PubMed

    Anastasiou, Evilena; Mitchell, Piers D

    2013-10-01

    The development of molecular tools for the extraction, analysis and interpretation of DNA from the remains of ancient organisms (paleogenetics) has revolutionised a range of disciplines as diverse as the fields of human evolution, bioarchaeology, epidemiology, microbiology, taxonomy and population genetics. The paper draws attention to some of the challenges associated with the extraction and interpretation of ancient DNA from archaeological material, and then reviews the influence of paleogenetics on the field of human evolution. It discusses the main contributions of molecular studies to reconstructing the evolutionary and phylogenetic relationships between extinct hominins (human ancestors) and anatomically modern humans. It also explores the evidence for evolutionary changes in the genetic structure of anatomically modern humans in recent millennia. This breadth of research has led to discoveries that would never have been possible using traditional approaches to human evolution. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Invariance property of wave scattering through disordered media

    PubMed Central

    Pierrat, Romain; Ambichl, Philipp; Gigan, Sylvain; Haber, Alexander; Carminati, Rémi; Rotter, Stefan

    2014-01-01

    A fundamental insight in the theory of diffusive random walks is that the mean length of trajectories traversing a finite open system is independent of the details of the diffusion process. Instead, the mean trajectory length depends only on the system's boundary geometry and is thus unaffected by the value of the mean free path. Here we show that this result is rooted on a much deeper level than that of a random walk, which allows us to extend the reach of this universal invariance property beyond the diffusion approximation. Specifically, we demonstrate that an equivalent invariance relation also holds for the scattering of waves in resonant structures as well as in ballistic, chaotic or in Anderson localized systems. Our work unifies a number of specific observations made in quite diverse fields of science ranging from the movement of ants to nuclear scattering theory. Potential experimental realizations using light fields in disordered media are discussed. PMID:25425671

  12. An active acoustic tripwire for simultaneous detection and localization of multiple underwater intruders.

    PubMed

    Folegot, Thomas; Martinelli, Giovanna; Guerrini, Piero; Stevenson, J Mark

    2008-11-01

    An algorithm allowing simultaneous detection and localization of multiple submerged targets crossing an acoustic tripwire based on forward scattering is described and then evaluated based upon data collected at sea. This paper quantifies the agreement between the theoretical performance and the results obtained from processing data gathered at sea for crossings at several depths and ranges. Targets crossing the acoustic field produce shadows on each side of the barrier, for specific sensors and for specific acoustic paths. In post-processing, a model is invoked to associate expected paths with the observed shadows. This process allows triangulation of the target's position inside the acoustic field. Precise localization is achieved by taking advantage of the multipath propagation structure of the received signal, together with the diversity of the source and receiver locations. Environmental robustness is demonstrated using simulations and can be explained by the use of an array of sources spatially distributed through the water column.

  13. Roadmap of optical communications

    NASA Astrophysics Data System (ADS)

    Agrell, Erik; Karlsson, Magnus; Chraplyvy, A. R.; Richardson, David J.; Krummrich, Peter M.; Winzer, Peter; Roberts, Kim; Fischer, Johannes Karl; Savory, Seb J.; Eggleton, Benjamin J.; Secondini, Marco; Kschischang, Frank R.; Lord, Andrew; Prat, Josep; Tomkos, Ioannis; Bowers, John E.; Srinivasan, Sudha; Brandt-Pearce, Maïté; Gisin, Nicolas

    2016-06-01

    Lightwave communications is a necessity for the information age. Optical links provide enormous bandwidth, and the optical fiber is the only medium that can meet the modern society's needs for transporting massive amounts of data over long distances. Applications range from global high-capacity networks, which constitute the backbone of the internet, to the massively parallel interconnects that provide data connectivity inside datacenters and supercomputers. Optical communications is a diverse and rapidly changing field, where experts in photonics, communications, electronics, and signal processing work side by side to meet the ever-increasing demands for higher capacity, lower cost, and lower energy consumption, while adapting the system design to novel services and technologies. Due to the interdisciplinary nature of this rich research field, Journal of Optics has invited 16 researchers, each a world-leading expert in their respective subfields, to contribute a section to this invited review article, summarizing their views on state-of-the-art and future developments in optical communications.

  14. KSC-08pd2451

    NASA Image and Video Library

    2008-08-16

    CAPE CANAVERAL, Fla. – Technicians in the Payload Hazardous Servicing Facility complete removal of the protective cover from the Wide Field Camera 3, or WFC3. The WFC3 is part of the payload on space shuttle Atlantis for the fifth and final Hubble servicing mission, STS-125. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Jack Pfaller

  15. KSC-08pd2393

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, an overhead crane is moved above the Wide Field Camera 3, or WFC3, for attachment. The WFC3 will be lifted and transferred to a work stand. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  16. KSC-08pd2453

    NASA Image and Video Library

    2008-08-18

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, technicians check the Wide Field Camera 3, or WFC3, after removal of its protective cover. WFC3 is part of the payload on space shuttle Atlantis' STS-125 mission for the fifth and final Hubble servicing flight to NASA's Hubble Space Telescope. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Amanda Diller

  17. KSC-08pd2454

    NASA Image and Video Library

    2008-08-18

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, technicians check the Wide Field Camera 3, or WFC3, after removal of its protective cover. WFC3 is part of the payload on space shuttle Atlantis' STS-125 mission for the fifth and final Hubble servicing flight to NASA's Hubble Space Telescope. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Amanda Diller

  18. KSC-08pd2474

    NASA Image and Video Library

    2008-08-18

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, the Wide Field Camera 3, or WFC3, is lowered onto the Super Lightweight Interchangeable Carrier. WFC3 is part of the payload on space shuttle Atlantis' STS-125 mission for the fifth and final Hubble servicing flight to NASA's Hubble Space Telescope. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Amanda Diller

  19. KSC-08pd2472

    NASA Image and Video Library

    2008-08-18

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, the Wide Field Camera 3, or WFC3, is moved toward the Super Lightweight Interchangeable Carrier. WFC3 is part of the payload on space shuttle Atlantis' STS-125 mission for the fifth and final Hubble servicing flight to NASA's Hubble Space Telescope. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Amanda Diller

  20. KSC-08pd2473

    NASA Image and Video Library

    2008-08-18

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, the Wide Field Camera 3, or WFC3, is lowered toward the Super Lightweight Interchangeable Carrier. WFC3 is part of the payload on space shuttle Atlantis' STS-125 mission for the fifth and final Hubble servicing flight to NASA's Hubble Space Telescope. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Amanda Diller

  1. KSC-08pd2471

    NASA Image and Video Library

    2008-08-18

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, an overhead crane lifts the Wide Field Camera 3, or WFC3, above the stand holding the Super Lightweight Interchangeable Carrier. WFC3 is part of the payload on space shuttle Atlantis' STS-125 mission for the fifth and final Hubble servicing flight to NASA's Hubble Space Telescope. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Amanda Diller

  2. KSC-08pd2458

    NASA Image and Video Library

    2008-08-18

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, the Wide Field Camera 3, or WFC3, is ready to be transferred to the Super Lightweight Interchangeable Carrier. WFC3 is part of the payload on space shuttle Atlantis' STS-125 mission for the fifth and final Hubble servicing flight to NASA's Hubble Space Telescope. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Amanda Diller

  3. KSC-08pd2448

    NASA Image and Video Library

    2008-08-16

    CAPE CANAVERAL, Fla. – The Wide Field Camera 3, or WFC3, rests on a work stand in the Payload Hazardous Servicing Facility since its arrival Aug. 12. WFC3 is part of the payload on space shuttle Atlantis for the fifth and final Hubble servicing mission, STS-125. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Jack Pfaller

  4. KSC-08pd2394

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, an overhead crane begins to lift the Wide Field Camera 3, or WFC3, from the base of the shipping container. The WFC3 will be transferred to a work stand. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  5. KSC-08pd2395

    NASA Image and Video Library

    2008-08-12

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, an overhead crane lifts the Wide Field Camera 3, or WFC3, from the base of the shipping container. The WFC3 will be transferred to a work stand. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. WFC3 is part of the payload on the fifth and final Hubble servicing mission, STS-125, targeted for launch Oct. 8. Photo credit: NASA/Jack Pfaller

  6. KSC-08pd2452

    NASA Image and Video Library

    2008-08-16

    CAPE CANAVERAL, Fla. – Technicians in the Payload Hazardous Servicing Facility complete removal of the protective cover from the Wide Field Camera 3, or WFC3. The WFC3 is part of the payload on space shuttle Atlantis for the fifth and final Hubble servicing mission, STS-125. As Hubble enters the last stage of its life, WFC3 will be Hubble's next evolutionary step, allowing Hubble to peer ever further into the mysteries of the cosmos. WFC3 will study a diverse range of objects and phenomena, from young and extremely distant galaxies, to much more nearby stellar systems, to objects within our very own solar system. WFC3 will take the place of Wide Field Planetary Camera 2, which astronauts will bring back to Earth aboard the shuttle. Launch of Atlantis is targeted at 1:34 a.m. EDT Oct. 8. Photo credit: NASA/Jack Pfaller

  7. Systematic Parameterization of Lignin for the CHARMM Force Field

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vermaas, Joshua; Petridis, Loukas; Beckham, Gregg

    Plant cell walls have three primary components, cellulose, hemicellulose, and lignin, the latter of which is a recalcitrant, aromatic heteropolymer that provides structure to plants, water and nutrient transport through plant tissues, and a highly effective defense against pathogens. Overcoming the recalcitrance of lignin is key to effective biomass deconstruction, which would in turn enable the use of biomass as a feedstock for industrial processes. Our understanding of lignin structure in the plant cell wall is hampered by the limitations of the available lignin forcefields, which currently only account for a single linkage between lignins and lack explicit parameterization formore » emerging lignin structures both from natural variants and engineered lignin structures. Since polymerization of lignin occurs via radical intermediates, multiple C-O and C-C linkages have been isolated , and the current force field only represents a small subset of lignin the diverse lignin structures found in plants. In order to take into account the wide range of lignin polymerization chemistries, monomers and dimer combinations of C-, H-, G-, and S-lignins as well as with hydroxycinnamic acid linkages were subjected to extensive quantum mechanical calculations to establish target data from which to build a complete molecular mechanics force field tuned specifically for diverse lignins. This was carried out in a GPU-accelerated global optimization process, whereby all molecules were parameterized simultaneously using the same internal parameter set. By parameterizing lignin specifically, we are able to more accurately represent the interactions and conformations of lignin monomers and dimers relative to a general force field. This new force field will enables computational researchers to study the effects of different linkages on the structure of lignin, as well as construct more accurate plant cell wall models based on observed statistical distributions of lignin that differ between disparate feedstocks, and guide further lignin engineering efforts.« less

  8. Disturbance Regimes Predictably Alter Diversity in an Ecologically Complex Bacterial System

    PubMed Central

    Scholz, Monika; Hutchison, Alan L.; Dinner, Aaron R.; Gilbert, Jack A.; Coleman, Maureen L.

    2016-01-01

    ABSTRACT Diversity is often associated with the functional stability of ecological communities from microbes to macroorganisms. Understanding how diversity responds to environmental perturbations and the consequences of this relationship for ecosystem function are thus central challenges in microbial ecology. Unimodal diversity-disturbance relationships, in which maximum diversity occurs at intermediate levels of disturbance, have been predicted for ecosystems where life history tradeoffs separate organisms along a disturbance gradient. However, empirical support for such peaked relationships in macrosystems is mixed, and few studies have explored these relationships in microbial systems. Here we use complex microbial microcosm communities to systematically determine diversity-disturbance relationships over a range of disturbance regimes. We observed a reproducible switch between community states, which gave rise to transient diversity maxima when community states were forced to mix. Communities showed reduced compositional stability when diversity was highest. To further explore these dynamics, we formulated a simple model that reveals specific regimes under which diversity maxima are stable. Together, our results show how both unimodal and non-unimodal diversity-disturbance relationships can be observed as a system switches between two distinct microbial community states; this process likely occurs across a wide range of spatially and temporally heterogeneous microbial ecosystems. PMID:27999158

  9. A novel symbiovar (aegeanense) of the genus Ensifer nodulates Vigna unguiculata.

    PubMed

    Tampakaki, Anastasia P; Fotiadis, Christos T; Ntatsi, Georgia; Savvas, Dimitrios

    2017-10-01

    Cowpea (Vigna unguiculata) forms nitrogen-fixing root nodules with diverse symbiotic bacteria, mainly slow-growing rhizobial species belonging to the genus Bradyrhizobium, although a few studies have reported the isolation of fast-growing rhizobia under laboratory and field conditions. Although much research has been done on cowpea-nodulating bacteria in various countries around the world, very limited information is available on cowpea rhizobia in European soils. The aim of this study was to study the genetic and phenotypic diversity of indigenous cowpea-nodulating rhizobia in Greece. The genetic diversity of indigenous rhizobia associated with cowpea was investigated through a polyphasic approach. ERIC-PCR based fingerprinting analysis grouped the isolates into three groups. Based on the analysis of the 16S rRNA genes, IGS and on the concatenation of six housekeeping genes (recA, glnII, gyrB, truA, thrA and SMc00019), rhizobial isolates were classified within the species Ensifer fredii. However, symbiotic gene phylogenies, based on nodC, nifH and rhcRST genes, showed that the Ensifer isolates are markedly diverged from type and reference strains of E. fredii and formed one clearly separate cluster. The E. fredii strains were able to nodulate and fix nitrogen in cowpea but not in soybean and common bean. The present study showed that cowpea is nodulated under field conditions by fast-growing rhizobia belonging to the species E. fredii. Based on the phylogenies, similarity levels of symbiotic genes and the host range, the Ensifer isolates may constitute a new symbiovar for which the name 'aegeanense' is proposed. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  10. Asian longhorned beetle complicates the relationship between taxonomic diversity and pest vulnerability in street tree assemblages

    EPA Science Inventory

    Urban foresters routinely emphasise the importance of taxonomic diversity to reduce the vulnerability of tree assemblages to invasive pests, but it is unclear to what extent diversity reduces vulnerability to polyphagous (i.e. generalist) pests. Drawing on field data from seven c...

  11. The State of Multiculturalism and Diversity in Undergraduate Psychology Training

    ERIC Educational Resources Information Center

    Fuentes, Milton A.; Shannon, Casey R.

    2016-01-01

    Over the past few decades, diversity and multiculturalism have received considerable attention in the field of psychology. While there have been notable efforts to ensure these important areas are addressed in undergraduate psychology training, little is known about this undertaking. The present study examined how diversity and multiculturalism…

  12. Research Report for the Organizing for Diversity Project.

    ERIC Educational Resources Information Center

    Betsinger, Alicia M.; Garcia, Shernaz B.; Guerra, Patricia L.

    This report describes the Organizing for Diversity Project, which generated professional development modules to prepare teachers to work more effectively with diverse students. Prototype modules were developed in collaboration with teacher volunteers, then field tested. The final 11 modules, which included 33 hours of training, were designed for…

  13. Preparing Future Librarians to Effectively Serve Their Communities

    ERIC Educational Resources Information Center

    Jaeger, Paul T.; Bertot, John Carlo; Subramaniam, Mega

    2013-01-01

    The field of library and information science (LIS) continues to struggle with the issue of diversity and inclusion. As we are perpetually working to increase racial and gender diversity in the profession, the definition of diversity continues to broaden to include socioeconomic status, education, language, literacy, age, sexual orientation,…

  14. Forensic science, genetics and wildlife biology: getting the right mix for a wildlife DNA forensics lab.

    PubMed

    Ogden, Rob

    2010-09-01

    Wildlife DNA forensics is receiving increasing coverage in the popular press and has begun to appear in the scientific literature in relation to several different fields. Recognized as an applied subject, it rests on top of very diverse scientific pillars ranging from biochemistry through to evolutionary genetics, all embedded within the context of modern forensic science. This breadth of scope, combined with typically limited resources, has often left wildlife DNA forensics hanging precariously between human DNA forensics and academics keen to seek novel applications for biological research. How best to bridge this gap is a matter for regular debate among the relatively few full-time practitioners in the field. The decisions involved in establishing forensic genetic services to investigate wildlife crime can be complex, particularly where crimes involve a wide range of species and evidential questions. This paper examines some of the issues relevant to setting up a wildlife DNA forensics laboratory based on experiences of working in this area over the past 7 years. It includes a discussion of various models for operating individual laboratories as well as options for organizing forensic testing at higher national and international levels.

  15. Stress-strain behaviour analysis of Middle Polish glacial tills from Warsaw (Poland) based on the interpretation of advanced field and laboratory tests

    NASA Astrophysics Data System (ADS)

    Bąkowska, Anna; Dobak, Dobak; Gawriuczenkow, Ireneusz; Kiełbasiński, Kamil; Szczepański, Tomasz; Trzciński, Jerzy; Wójcik, Emilia; Zawrzykraj, Piotr

    2016-09-01

    The selected parameters of the Wartanian and Odranian tills, with relation to their spatial occurrence, grain size distribution, mineralogical composition, matric suction and other physical characteristics, are presented. The assessment of the lithogenesis and stress history on the microstructure is attempted. The comparison of the compression and permeability characteristics from field and laboratory tests has been performed. Laboratory consolidation tests carried out with up to 20MPa vertical stress, revealed two yield stress values, one in the range of a couple hundreds kPa, the other in the range of a couple thousands kPa. Based on those results, the reliability of the soil preconsolidation assessment, with the use of the two different methods is discussed. The aspect of the triaxial strength reduction under the dynamic loading of diverse frequency and amplitude is raised. The research results depict a variety of possible geological-engineering characteristics, under the divergent constraints scenarios, of compression or strength weakening origin. The effects of the specialized research program will widen the possibilities of physio-mechanical and structural characterization of soils for geological-engineering purposes.

  16. Neural and neurochemical basis of reinforcement-guided decision making.

    PubMed

    Khani, Abbas; Rainer, Gregor

    2016-08-01

    Decision making is an adaptive behavior that takes into account several internal and external input variables and leads to the choice of a course of action over other available and often competing alternatives. While it has been studied in diverse fields ranging from mathematics, economics, ecology, and ethology to psychology and neuroscience, recent cross talk among perspectives from different fields has yielded novel descriptions of decision processes. Reinforcement-guided decision making models are based on economic and reinforcement learning theories, and their focus is on the maximization of acquired benefit over a defined period of time. Studies based on reinforcement-guided decision making have implicated a large network of neural circuits across the brain. This network includes a wide range of cortical (e.g., orbitofrontal cortex and anterior cingulate cortex) and subcortical (e.g., nucleus accumbens and subthalamic nucleus) brain areas and uses several neurotransmitter systems (e.g., dopaminergic and serotonergic systems) to communicate and process decision-related information. This review discusses distinct as well as overlapping contributions of these networks and neurotransmitter systems to the processing of decision making. We end the review by touching on neural circuitry and neuromodulatory regulation of exploratory decision making. Copyright © 2016 the American Physiological Society.

  17. Interaction between drug delivery vehicles and cells under the effect of shear stress.

    PubMed

    Godoy-Gallardo, M; Ek, P K; Jansman, M M T; Wohl, B M; Hosta-Rigau, L

    2015-09-01

    Over the last decades, researchers have developed an ever greater and more ingenious variety of drug delivery vehicles (DDVs). This has made it possible to encapsulate a wide selection of therapeutic agents, ranging from proteins, enzymes, and peptides to hydrophilic and hydrophobic small drugs while, at the same time, allowing for drug release to be triggered through a diverse range of physical and chemical cues. While these advances are impressive, the field has been lacking behind in translating these systems into the clinic, mainly due to low predictability of in vitro and rodent in vivo models. An important factor within the complex and dynamic human in vivo environment is the shear flow observed within our circulatory system and many other tissues. Within this review, recent advances to leverage microfluidic devices to better mimic these conditions through novel in vitro assays are summarized. By grouping the discussion in three prominent classes of DDVs (lipidic and polymeric particles as well as inorganic nanoparticles), we hope to guide researchers within drug delivery into this exciting field and advance a further implementation of these assay systems within the development of DDVs.

  18. Silage Collected from Dairy Farms Harbors an Abundance of Listeriaphages with Considerable Host Range and Genome Size Diversity

    PubMed Central

    Vongkamjan, Kitiya; Switt, Andrea Moreno; den Bakker, Henk C.; Fortes, Esther D.

    2012-01-01

    Since the food-borne pathogen Listeria monocytogenes is common in dairy farm environments, it is likely that phages infecting this bacterium (“listeriaphages”) are abundant on dairy farms. To better understand the ecology and diversity of listeriaphages on dairy farms and to develop a diverse phage collection for further studies, silage samples collected on two dairy farms were screened for L. monocytogenes and listeriaphages. While only 4.5% of silage samples tested positive for L. monocytogenes, 47.8% of samples were positive for listeriaphages, containing up to >1.5 × 104 PFU/g. Host range characterization of the 114 phage isolates obtained, with a reference set of 13 L. monocytogenes strains representing the nine major serotypes and four lineages, revealed considerable host range diversity; phage isolates were classified into nine lysis groups. While one serotype 3c strain was not lysed by any phage isolates, serotype 4 strains were highly susceptible to phages and were lysed by 63.2 to 88.6% of phages tested. Overall, 12.3% of phage isolates showed a narrow host range (lysing 1 to 5 strains), while 28.9% of phages represented broad host range (lysing ≥11 strains). Genome sizes of the phage isolates were estimated to range from approximately 26 to 140 kb. The extensive host range and genomic diversity of phages observed here suggest an important role of phages in the ecology of L. monocytogenes on dairy farms. In addition, the phage collection developed here has the potential to facilitate further development of phage-based biocontrol strategies (e.g., in silage) and other phage-based tools. PMID:23042180

  19. Approaches to culture and diversity: A critical synthesis of occupational therapy literature.

    PubMed

    Beagan, Brenda L

    2015-12-01

    The 2007 position statement on diversity for the Canadian occupational therapy profession argued discussion was needed to determine the implications of approaches to working with cultural differences and other forms of diversity. In 2014, a new position statement on diversity was published, emphasizing the importance of social power relations and power relations between client and therapist, and supporting two particular approaches: cultural safety and cultural humility with critical reflexivity This paper reviews and critically synthesizes the literature concerning culture and diversity published in occupational therapy between 2007 and 2014, tracing the major discourses and mapping the implications of four differing approaches: cultural competence, cultural relevance, cultural safety, and cultural humility. Approaches differ in where they situate the "problem," how they envision change, the end goal, and the application to a range of types of diversity. The latter two are preferred approaches for their attention to power relations and potential to encompass a range of types of social and cultural diversity. © CAOT 2015.

  20. Monitoring the impact of Bt maize on butterflies in the field: estimation of required sample sizes.

    PubMed

    Lang, Andreas

    2004-01-01

    The monitoring of genetically modified organisms (GMOs) after deliberate release is important in order to assess and evaluate possible environmental effects. Concerns have been raised that the transgenic crop, Bt maize, may affect butterflies occurring in field margins. Therefore, a monitoring of butterflies was suggested accompanying the commercial cultivation of Bt maize. In this study, baseline data on the butterfly species and their abundance in maize field margins is presented together with implications for butterfly monitoring. The study was conducted in Bavaria, South Germany, between 2000-2002. A total of 33 butterfly species was recorded in field margins. A small number of species dominated the community, and butterflies observed were mostly common species. Observation duration was the most important factor influencing the monitoring results. Field margin size affected the butterfly abundance, and habitat diversity had a tendency to influence species richness. Sample size and statistical power analyses indicated that a sample size in the range of 75 to 150 field margins for treatment (transgenic maize) and control (conventional maize) would detect (power of 80%) effects larger than 15% in species richness and the butterfly abundance pooled across species. However, a much higher number of field margins must be sampled in order to achieve a higher statistical power, to detect smaller effects, and to monitor single butterfly species.

  1. Women of Color Chief Diversity Officers: Their Positionality and Agency in Higher Education Institutions

    ERIC Educational Resources Information Center

    Nixon, Monica L.

    2013-01-01

    Colleges and universities are seen as sites for harnessing for the common good the challenges and opportunities associated with diversity. Research supports the link of diversity experiences with a range of individual, institutional, and societal benefits. Contemporary models of operationalizing diversity on college campuses focus on the…

  2. Web-based resources for mass-spectrometry-based metabolomics: a user's guide.

    PubMed

    Tohge, Takayuki; Fernie, Alisdair R

    2009-03-01

    In recent years, a plethora of web-based tools aimed at supporting mass-spectrometry-based metabolite profiling and metabolomics applications have appeared. Given the huge hurdles presented by the chemical diversity and dynamic range of the metabolites present in the plant kingdom, profiling the levels of a broad range of metabolites is highly challenging. Given the scale and costs involved in defining the plant metabolome, it is imperative that data are effectively shared between laboratories pursuing this goal. However, ensuring accurate comparison of samples run on the same machine within the same laboratory, let alone cross-machine and cross-laboratory comparisons, requires both careful experimentation and data interpretation. In this review, we present an overview of currently available software that aids either in peak identification or in the related field of peak alignment as well as those with utility in defining structural information of compounds and metabolic pathways.

  3. Applications of biological pores in nanomedicine, sensing, and nanoelectronics.

    PubMed

    Majd, Sheereen; Yusko, Erik C; Billeh, Yazan N; Macrae, Michael X; Yang, Jerry; Mayer, Michael

    2010-08-01

    Biological protein pores and pore-forming peptides can generate a pathway for the flux of ions and other charged or polar molecules across cellular membranes. In nature, these nanopores have diverse and essential functions that range from maintaining cell homeostasis and participating in cell signaling to activating or killing cells. The combination of the nanoscale dimensions and sophisticated - often regulated - functionality of these biological pores make them particularly attractive for the growing field of nanobiotechnology. Applications range from single-molecule sensing to drug delivery and targeted killing of malignant cells. Potential future applications may include the use of nanopores for single strand DNA sequencing and for generating bio-inspired, and possibly, biocompatible visual detection systems and batteries. This article reviews the current state of applications of pore-forming peptides and proteins in nanomedicine, sensing, and nanoelectronics. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Distance, elevation and environment as drivers of diversity and divergence in bumble bees across latitude and altitude.

    PubMed

    Jackson, Jason M; Pimsler, Meaghan L; Oyen, Kennan Jeannet; Koch-Uhuad, Jonathan B; Herndon, James D; Strange, James P; Dillon, Michael E; Lozier, Jeffrey D

    2018-06-04

    Identifying drivers of dispersal limitation and genetic differentiation is a key goal in biogeography. We examine patterns of population connectivity and genetic diversity using restriction site-associated DNA sequencing (RADseq) in two bumble bee species, Bombus vosnesenskii and Bombus bifarius, across latitude and altitude in mountain ranges from California, Oregon and Washington, U.S.A. Bombus vosnesenskii, which occurs across a broader elevational range at most latitudes, exhibits little population structure while B. bifarius, which occupies a relatively narrow higher elevation niche across most latitudes, exhibits much stronger population differentiation, although gene flow in both species is best explained by isolation with environmental niche resistance. A relationship between elevational habitat breadth and genetic diversity is also apparent, with B. vosnesenskii exhibiting relatively consistent levels of genetic diversity across its range, while B. bifarius has reduced genetic diversity at low latitudes, where it is restricted to high-elevation habitat. The results of this study highlight the importance of the intersect between elevational range and habitat suitability in influencing population connectivity and suggest that future climate warming will have a fragmenting effect even on populations that are presently well connected, as they track their thermal niches upward in montane systems. © 2018 John Wiley & Sons Ltd.

  5. Seasonal variations in the diversity and abundance of diazotrophic communities across soils.

    PubMed

    Pereira e Silva, Michele C; Semenov, Alexander V; van Elsas, Jan Dirk; Salles, Joana Falcão

    2011-07-01

    The nitrogen (N)-fixing community is a key functional community in soil, as it replenishes the pool of biologically available N that is lost to the atmosphere via anaerobic ammonium oxidation and denitrification. We characterized the structure and dynamic changes in diazotrophic communities, based on the nifH gene, across eight different representative Dutch soils during one complete growing season, to evaluate the amplitude of the natural variation in abundance and diversity, and identify possible relationships with abiotic factors. Overall, our results indicate that soil type is the main factor influencing the N-fixing communities, which were more abundant and diverse in the clay soils (n=4) than in the sandy soils (n=4). On average, the amplitude of variation in community size as well as the range-weighted richness were also found to be higher in the clay soils. These results indicate that N-fixing communities associated with sandy and clay soil show a distinct amplitude of variation under field conditions, and suggest that the diazotrophic communities associated with clay soil might be more sensitive to fluctuations associated with the season and agricultural practices. Moreover, soil characteristics such as ammonium content, pH and texture most strongly correlated with the variations observed in the diversity, size and structure of N-fixing communities, whose relative importance was determined across a temporal and spatial scale. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  6. Hydration dynamics promote bacterial coexistence on rough surfaces

    PubMed Central

    Wang, Gang; Or, Dani

    2013-01-01

    Identification of mechanisms that promote and maintain the immense microbial diversity found in soil is a central challenge for contemporary microbial ecology. Quantitative tools for systematic integration of complex biophysical and trophic processes at spatial scales, relevant for individual cell interactions, are essential for making progress. We report a modeling study of competing bacterial populations cohabiting soil surfaces subjected to highly dynamic hydration conditions. The model explicitly tracks growth, motion and life histories of individual bacterial cells on surfaces spanning dynamic aqueous networks that shape heterogeneous nutrient fields. The range of hydration conditions that confer physical advantages for rapidly growing species and support competitive exclusion is surprisingly narrow. The rapid fragmentation of soil aqueous phase under most natural conditions suppresses bacterial growth and cell dispersion, thereby balancing conditions experienced by competing populations with diverse physiological traits. In addition, hydration fluctuations intensify localized interactions that promote coexistence through disproportional effects within densely populated regions during dry periods. Consequently, bacterial population dynamics is affected well beyond responses predicted from equivalent and uniform hydration conditions. New insights on hydration dynamics could be considered in future designs of soil bioremediation activities, affect longevity of dry food products, and advance basic understanding of bacterial diversity dynamics and its role in global biogeochemical cycles. PMID:23051694

  7. Associations of Leaf Spectra with Genetic and Phylogenetic Variation in Oaks: Prospects for Remote Detection of Biodiversity

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cavender-Bares, Jeannine; Meireles, Jose; Couture, John

    Species and phylogenetic lineages have evolved to differ in the way that they acquire and deploy resources, with consequences for their physiological, chemical and structural attributes, many of which can be detected using spectral reflectance form leaves. Recent technological advances for assessing optical properties of plants offer opportunities to detect functional traits of organisms and differentiate levels of biological organization across the tree of life. We connect leaf-level full range spectral data (400–2400 nm) of leaves to the hierarchical organization of plant diversity within the oak genus (Quercus) using field and greenhouse experiments in which environmental factors and plant agemore » are controlled. We show that spectral data significantly differentiate populations within a species and that spectral similarity is significantly associated with phylogenetic similarity among species. Furthermore, we show that hyperspectral information allows more accurate classification of taxa than spectrally-derived traits, which by definition are of lower dimensionality. Finally, model accuracy increases at higher levels in the hierarchical organization of plant diversity, such that we are able to better distinguish clades than species or populations. This pattern supports an evolutionary explanation for the degree of optical differentiation among plants and demonstrates potential for remote detection of genetic and phylogenetic diversity.« less

  8. Microbial Functional Gene Diversity Predicts Groundwater Contamination and Ecosystem Functioning

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    He, Zhili; Zhang, Ping; Wu, Linwei

    Contamination from anthropogenic activities has significantly impacted Earth’s biosphere. However, knowledge about how environmental contamination affects the biodiversity of groundwater microbiomes and ecosystem functioning remains very limited. Here, we used a comprehensive functional gene array to analyze groundwater microbiomes from 69 wells at the Oak Ridge Field Research Center (Oak Ridge, TN), representing a wide pH range and uranium, nitrate, and other contaminants. We hypothesized that the functional diversity of groundwater microbiomes would decrease as environmental contamination (e.g., uranium or nitrate) increased or at low or high pH, while some specific populations capable of utilizing or resistant to those contaminantsmore » would increase, and thus, such key microbial functional genes and/or populations could be used to predict groundwater contamination and ecosystem functioning. Our results indicated that functional richness/diversity decreased as uranium (but not nitrate) increased in groundwater. In addition, about 5.9% of specific key functional populations targeted by a comprehensive functional gene array (GeoChip 5) increased significantly (P < 0.05) as uranium or nitrate increased, and their changes could be used to successfully predict uranium and nitrate contamination and ecosystem functioning. Here, this study indicates great potential for using microbial functional genes to predict environmental contamination and ecosystem functioning.« less

  9. Microbial Functional Gene Diversity Predicts Groundwater Contamination and Ecosystem Functioning

    PubMed Central

    Zhang, Ping; Wu, Linwei; Rocha, Andrea M.; Shi, Zhou; Wu, Bo; Qin, Yujia; Wang, Jianjun; Yan, Qingyun; Curtis, Daniel; Ning, Daliang; Van Nostrand, Joy D.; Wu, Liyou; Watson, David B.; Adams, Michael W. W.; Alm, Eric J.; Adams, Paul D.; Arkin, Adam P.

    2018-01-01

    ABSTRACT Contamination from anthropogenic activities has significantly impacted Earth’s biosphere. However, knowledge about how environmental contamination affects the biodiversity of groundwater microbiomes and ecosystem functioning remains very limited. Here, we used a comprehensive functional gene array to analyze groundwater microbiomes from 69 wells at the Oak Ridge Field Research Center (Oak Ridge, TN), representing a wide pH range and uranium, nitrate, and other contaminants. We hypothesized that the functional diversity of groundwater microbiomes would decrease as environmental contamination (e.g., uranium or nitrate) increased or at low or high pH, while some specific populations capable of utilizing or resistant to those contaminants would increase, and thus, such key microbial functional genes and/or populations could be used to predict groundwater contamination and ecosystem functioning. Our results indicated that functional richness/diversity decreased as uranium (but not nitrate) increased in groundwater. In addition, about 5.9% of specific key functional populations targeted by a comprehensive functional gene array (GeoChip 5) increased significantly (P < 0.05) as uranium or nitrate increased, and their changes could be used to successfully predict uranium and nitrate contamination and ecosystem functioning. This study indicates great potential for using microbial functional genes to predict environmental contamination and ecosystem functioning. PMID:29463661

  10. Microbial Functional Gene Diversity Predicts Groundwater Contamination and Ecosystem Functioning

    DOE PAGES

    He, Zhili; Zhang, Ping; Wu, Linwei; ...

    2018-02-20

    Contamination from anthropogenic activities has significantly impacted Earth’s biosphere. However, knowledge about how environmental contamination affects the biodiversity of groundwater microbiomes and ecosystem functioning remains very limited. Here, we used a comprehensive functional gene array to analyze groundwater microbiomes from 69 wells at the Oak Ridge Field Research Center (Oak Ridge, TN), representing a wide pH range and uranium, nitrate, and other contaminants. We hypothesized that the functional diversity of groundwater microbiomes would decrease as environmental contamination (e.g., uranium or nitrate) increased or at low or high pH, while some specific populations capable of utilizing or resistant to those contaminantsmore » would increase, and thus, such key microbial functional genes and/or populations could be used to predict groundwater contamination and ecosystem functioning. Our results indicated that functional richness/diversity decreased as uranium (but not nitrate) increased in groundwater. In addition, about 5.9% of specific key functional populations targeted by a comprehensive functional gene array (GeoChip 5) increased significantly (P < 0.05) as uranium or nitrate increased, and their changes could be used to successfully predict uranium and nitrate contamination and ecosystem functioning. Here, this study indicates great potential for using microbial functional genes to predict environmental contamination and ecosystem functioning.« less

  11. Historical mitochondrial diversity in African leopards (Panthera pardus) revealed by archival museum specimens.

    PubMed

    Anco, Corey; Kolokotronis, Sergios-Orestis; Henschel, Philipp; Cunningham, Seth W; Amato, George; Hekkala, Evon

    2018-04-01

    Once found throughout Africa and Eurasia, the leopard (Panthera pardus) was recently uplisted from Near Threatened to Vulnerable by the International Union for the Conservation of Nature (IUCN). Historically, more than 50% of the leopard's global range occurred in continental Africa, yet sampling from this part of the species' distribution is only sparsely represented in prior studies examining patterns of genetic variation at the continental or global level. Broad sampling to determine baseline patterns of genetic variation throughout the leopard's historical distribution is important, as these measures are currently used by the IUCN to direct conservation priorities and management plans. By including data from 182 historical museum specimens, faecal samples from ongoing field surveys, and published sequences representing sub-Saharan Africa, we identify previously unrecognized genetic diversity in African leopards. Our mtDNA data indicates high levels of divergence among regional populations and strongly differentiated lineages in West Africa on par with recent studies of other large vertebrates. We provide a reference benchmark of genetic diversity in African leopards against which future monitoring can be compared. These findings emphasize the utility of historical museum collections in understanding the processes that shape present biodiversity. Additionally, we suggest future research to clarify African leopard taxonomy and to differentiate between delineated units requiring monitoring or conservation action.

  12. The Other Kind of Rock: Diversifying Geosciences Outreach with some Tools from Rock n' Roll

    NASA Astrophysics Data System (ADS)

    Konecky, B. L.

    2015-12-01

    Music can communicate science at times when words and graphs fail. For this reason, earth scientists are increasingly using sounds and rhythms to capture the public's imagination while demonstrating technical concepts and sharing the societal impacts of their research. Musical approaches reach across the boundaries of perceptual learning style, age, gender, and life history. Music therefore makes science (and scientists) more approachable to a wide range of people. But in addition to its unique power for engaging diverse audiences, music-based outreach also sets an example for the geosciences' untapped potential as a public empowerment tool. Like many STEM fields, the music industry has long been criticized for poor inclusion of women and minorities. Rock n' roll camps for girls are answering this challenge by teaching music as a vessel for empowerment, with principles that can easily be adapted to geoscience outreach and education. The process of observing the planet is innately empowering; outreach programs that emphasize this in their design will take their impacts to the next level. Just as diversity in the scientific community benefits geoscience, geoscience also benefits diverse communities. This presentation will outline some principles and applications from the music world to achieving both of these aims.

  13. Associations of Leaf Spectra with Genetic and Phylogenetic Variation in Oaks: Prospects for Remote Detection of Biodiversity

    DOE PAGES

    Cavender-Bares, Jeannine; Meireles, Jose; Couture, John; ...

    2016-03-09

    Species and phylogenetic lineages have evolved to differ in the way that they acquire and deploy resources, with consequences for their physiological, chemical and structural attributes, many of which can be detected using spectral reflectance form leaves. Recent technological advances for assessing optical properties of plants offer opportunities to detect functional traits of organisms and differentiate levels of biological organization across the tree of life. We connect leaf-level full range spectral data (400–2400 nm) of leaves to the hierarchical organization of plant diversity within the oak genus (Quercus) using field and greenhouse experiments in which environmental factors and plant agemore » are controlled. We show that spectral data significantly differentiate populations within a species and that spectral similarity is significantly associated with phylogenetic similarity among species. Furthermore, we show that hyperspectral information allows more accurate classification of taxa than spectrally-derived traits, which by definition are of lower dimensionality. Finally, model accuracy increases at higher levels in the hierarchical organization of plant diversity, such that we are able to better distinguish clades than species or populations. This pattern supports an evolutionary explanation for the degree of optical differentiation among plants and demonstrates potential for remote detection of genetic and phylogenetic diversity.« less

  14. Landscape Context Affects Aphid Parasitism by Lysiphlebus testaceipes (Hymenoptera: Aphidiinae) in Wheat Fields.

    PubMed

    Elliott, Norman C; Brewer, Michael J; Giles, Kristopher L

    2018-04-12

    Winter wheat is Oklahoma's most widely grown crop, and is planted during September and October, grows from fall through spring, and is harvested in June. Winter wheat fields are typically interspersed in a mosaic of habitats in other uses, and we hypothesized that the spatial and temporal composition and configuration of landscape elements, which contribute to agroecosystem diversity also influence biological control of common aphid pests. The parasitoid Lysiphlebus testaceipes (Cresson; Hymenoptera: Aphidiinae) is highly effective at reducing aphid populations in wheat in Oklahoma, and though a great deal is known about the biology and ecology of L. testaceipes, there are gaps in knowledge that limit predicting when and where it will be effective at controlling aphid infestations in wheat. Our objective was to determine the influence of landscape structure on parasitism of cereal aphids by L. testaceipes in wheat fields early in the growing season when aphid and parasitoid colonization occurs and later in the growing season when aphid and parasitoid populations are established in wheat fields. Seventy fields were studied during the three growing seasons. Significant correlations between parasitism by L. testaceipes and landscape variables existed for patch density, fractal dimension, Shannon's patch diversity index, percent wheat, percent summer crops, and percent wooded land. Correlations between parasitism and landscape variables were generally greatest at a 3.2 km radius surrounding the wheat field. Correlations between parasitism and landscape variables that would be expected to increase with increasing landscape diversity were usually positive. Subsequent regression models for L. testaceipes parasitism in wheat fields in autumn and spring showed that landscape variables influenced parasitism and indicated that parasitism increased with increasing landscape diversity. Overall, results indicate that L. testaceipes utilizes multiple habitats throughout the year depending on their availability and acceptability, and frequently disperses among habitats. Colonization of wheat fields by L. testaceipes in autumn appears to be enhanced by proximity to fields of summer crops and semi-natural habitats other than grasslands.

  15. Natural Nanoparticles: A Particular Matter Inspired by Nature

    PubMed Central

    Griffin, Sharoon; Masood, Muhammad Irfan; Nasim, Muhammad Jawad; Sarfraz, Muhammad; Ebokaiwe, Azubuike Peter; Schäfer, Karl-Herbert; Keck, Cornelia M.; Jacob, Claus

    2017-01-01

    During the last couple of decades, the rapidly advancing field of nanotechnology has produced a wide palette of nanomaterials, most of which are considered as “synthetic” and, among the wider public, are often met with a certain suspicion. Despite the technological sophistication behind many of these materials, “nano” does not always equate with “artificial”. Indeed, nature itself is an excellent nanotechnologist. It provides us with a range of fine particles, from inorganic ash, soot, sulfur and mineral particles found in the air or in wells, to sulfur and selenium nanoparticles produced by many bacteria and yeasts. These nanomaterials are entirely natural, and, not surprisingly, there is a growing interest in the development of natural nanoproducts, for instance in the emerging fields of phyto- and phyco-nanotechnology. This review will highlight some of the most recent—and sometimes unexpected—advances in this exciting and diverse field of research and development. Naturally occurring nanomaterials, artificially produced nanomaterials of natural products as well as naturally occurring or produced nanomaterials of natural products all show their own, particular chemical and physical properties, biological activities and promise for applications, especially in the fields of medicine, nutrition, cosmetics and agriculture. In the future, such natural nanoparticles will not only stimulate research and add a greener outlook to a traditionally high-tech field, they will also provide solutions—pardon—suspensions for a range of problems. Here, we may anticipate specific biogenic factories, valuable new materials based on waste, the effective removal of contaminants as part of nano-bioremediation, and the conversion of poorly soluble substances and materials to biologically available forms for practical uses. PMID:29286304

  16. The Grism Lens-Amplified Survey from Space (GLASS). V. Extent and Spatial Distribution of Star Formation in z ~ 0.5 Cluster Galaxies

    NASA Astrophysics Data System (ADS)

    Vulcani, Benedetta; Treu, Tommaso; Schmidt, Kasper B.; Poggianti, Bianca M.; Dressler, Alan; Fontana, Adriano; Bradač, Marusa; Brammer, Gabriel B.; Hoag, Austin; Huang, Kuan-Han; Malkan, Matthew; Pentericci, Laura; Trenti, Michele; von der Linden, Anja; Abramson, Louis; He, Julie; Morris, Glenn

    2015-12-01

    We present the first study of the spatial distribution of star formation in z ˜ 0.5 cluster galaxies. The analysis is based on data taken with the Wide Field Camera 3 as part of the Grism Lens-Amplified Survey from Space (GLASS). We illustrate the methodology by focusing on two clusters (MACS 0717.5+3745 and MACS 1423.8+2404) with different morphologies (one relaxed and one merging) and use foreground and background galaxies as a field control sample. The cluster+field sample consists of 42 galaxies with stellar masses in the range 108-1011 M⊙ and star formation rates in the range 1-20 M⊙ yr-1. Both in clusters and in the field, Hα is more extended than the rest-frame UV continuum in 60% of the cases, consistent with diffuse star formation and inside-out growth. In ˜20% of the cases, the Hα emission appears more extended in cluster galaxies than in the field, pointing perhaps to ionized gas being stripped and/or star formation being enhanced at large radii. The peak of the Hα emission and that of the continuum are offset by less than 1 kpc. We investigate trends with the hot gas density as traced by the X-ray emission, and with the surface mass density as inferred from gravitational lens models, and find no conclusive results. The diversity of morphologies and sizes observed in Hα illustrates the complexity of the environmental processes that regulate star formation. Upcoming analysis of the full GLASS data set will increase our sample size by almost an order of magnitude, verifying and strengthening the inference from this initial data set.

  17. Landscape configurational heterogeneity by small-scale agriculture, not crop diversity, maintains pollinators and plant reproduction in western Europe.

    PubMed

    Hass, Annika L; Kormann, Urs G; Tscharntke, Teja; Clough, Yann; Baillod, Aliette Bosem; Sirami, Clélia; Fahrig, Lenore; Martin, Jean-Louis; Baudry, Jacques; Bertrand, Colette; Bosch, Jordi; Brotons, Lluís; Burel, Françoise; Georges, Romain; Giralt, David; Marcos-García, María Á; Ricarte, Antonio; Siriwardena, Gavin; Batáry, Péter

    2018-02-14

    Agricultural intensification is one of the main causes for the current biodiversity crisis. While reversing habitat loss on agricultural land is challenging, increasing the farmland configurational heterogeneity (higher field border density) and farmland compositional heterogeneity (higher crop diversity) has been proposed to counteract some habitat loss. Here, we tested whether increased farmland configurational and compositional heterogeneity promote wild pollinators and plant reproduction in 229 landscapes located in four major western European agricultural regions. High-field border density consistently increased wild bee abundance and seed set of radish ( Raphanus sativus ), probably through enhanced connectivity. In particular, we demonstrate the importance of crop-crop borders for pollinator movement as an additional experiment showed higher transfer of a pollen analogue along crop-crop borders than across fields or along semi-natural crop borders. By contrast, high crop diversity reduced bee abundance, probably due to an increase of crop types with particularly intensive management. This highlights the importance of crop identity when higher crop diversity is promoted. Our results show that small-scale agricultural systems can boost pollinators and plant reproduction. Agri-environmental policies should therefore aim to halt and reverse the current trend of increasing field sizes and to reduce the amount of crop types with particularly intensive management. © 2018 The Author(s).

  18. Insights into the sand fly saliva: Blood-feeding and immune interactions between sand flies, hosts, and Leishmania.

    PubMed

    Lestinova, Tereza; Rohousova, Iva; Sima, Michal; de Oliveira, Camila I; Volf, Petr

    2017-07-01

    Leishmaniases are parasitic diseases present worldwide that are transmitted to the vertebrate host by the bite of an infected sand fly during a blood feeding. Phlebotomine sand flies inoculate into the mammalian host Leishmania parasites embedded in promastigote secretory gel (PSG) with saliva, which is composed of a diverse group of molecules with pharmacological and immunomodulatory properties. In this review, we focus on 3 main aspects of sand fly salivary molecules: (1) structure and composition of salivary glands, including the properties of salivary molecules related to hemostasis and blood feeding, (2) immunomodulatory properties of salivary molecules and the diverse impacts of these molecules on leishmaniasis, ranging from disease exacerbation to vaccine development, and (3) use of salivary molecules for field applications, including monitoring host exposure to sand flies and the risk of Leishmania transmission. Studies showed interesting differences between salivary proteins of Phlebotomus and Lutzomyia species, however, no data were ever published on salivary proteins of Sergentomyia species. In the last 15 years, numerous studies have characterized sand fly salivary proteins and, in parallel, have addressed the impact of such molecules on the biology of the host-sand fly-parasite interaction. The results obtained shall pave the way for the development of field-application tools that could contribute to the management of leishmaniasis in endemic areas.

  19. Integrated knowledge-based tools for documenting and monitoring damages to built heritage

    NASA Astrophysics Data System (ADS)

    Cacciotti, R.

    2015-08-01

    The advancements of information technologies as applied to the most diverse fields of science define a breakthrough in the accessibility and processing of data for both expert and non-expert users. Nowadays it is possible to evidence an increasingly relevant research effort in the context of those domains, such as that of cultural heritage protection, in which knowledge mapping and sharing constitute critical prerequisites for accomplishing complex professional tasks. The aim of this paper is to outline the main results and outputs of the MONDIS research project. This project focusses on the development of integrated knowledge-based tools grounded on an ontological representation of the field of heritage conservation. The scope is to overcome the limitations of earlier databases by the application of modern semantic technologies able to integrate, organize and process useful information concerning damages to built heritage objects. In particular MONDIS addresses the need for supporting a diverse range of stakeholders (e.g. administrators, owners and professionals) in the documentation and monitoring of damages to historical constructions and in finding related remedies. The paper concentrates on the presentation of the following integrated knowledgebased components developed within the project: (I) MONDIS mobile application (plus desktop version), (II) MONDIS record explorer, (III) Ontomind profiles, (IV) knowledge matrix and (V) terminology editor. An example of practical application of the MONDIS integrated system is also provided and finally discussed.

  20. Bee communities along a prairie restoration chronosequence: similar abundance and diversity, distinct composition.

    PubMed

    Tonietto, Rebecca K; Ascher, John S; Larkin, Daniel J

    2017-04-01

    Recognition of the importance of bee conservation has grown in response to declines of managed honey bees and some wild bee species. Habitat loss has been implicated as a leading cause of declines, suggesting that ecological restoration is likely to play an increasing role in bee conservation efforts. In the midwestern United States, restoration of tallgrass prairie has traditionally targeted plant community objectives without explicit consideration for bees. However, restoration of prairie vegetation is likely to provide ancillary benefits to bees through increased foraging and nesting resources. We investigated community assembly of bees across a chronosequence of restored eastern tallgrass prairies and compared patterns to those in control and reference habitats (old fields and prairie remnants, respectively). We collected bees for 3 yr and measured diversity and abundance of in-bloom flowering plants, vegetation structure, ground cover, and surrounding land use as predictors of bee abundance and bee taxonomic and functional diversity. We found that site-level variables, but not site type or restoration age, were significant predictors of bee abundance (bloom diversity, P = 0.004; bare ground cover, P = 0.02) and bee diversity (bloom diversity, P = 0.01). There were significant correlations between overall composition of bee and blooming plant communities (Mantel test, P = 0.002), and both plant and bee assemblages in restorations were intermediate between those of old fields and remnant prairies. Restorations exhibited high bee beta diversity, i.e., restored sites' bee assemblages were taxonomically and functionally differentiated from each other. This pattern was strong in younger restorations (<20 yr old), but absent from older restorations (>20 yr), suggesting restored prairie bee communities become more similar to one another and more similar to remnant prairie bee communities over time with the arrival of more species and functional groups of bees. Our results indicate that old fields, restorations, and remnants provide habitat for diverse and abundant bee communities, but continued restoration of old fields will help support and conserve bee communities more similar to reference bee communities characteristic of remnant prairies. © 2016 by the Ecological Society of America.

  1. Snail species diversity impacts the infection patterns of Echinostoma spp.: Examples from field collected data.

    PubMed

    Zimmermann, Michael R; Luth, Kyle E; Esch, Gerald W

    2017-09-26

    Rapid losses of biodiversity due to the changing landscape have spurred increased interest in the role of species diversity and disease risk. A leading hypothesis for the importance of biodiversity in disease reduction is the dilution effect, which suggests that increasing species diversity within a system decreases the risk of disease among the organisms inhabiting it. The role of species diversity in trematode infection was investigated using field studies from sites across the U.S. to examine the impact of snail diversity in the infection dynamics of both first and second intermediate larval stages of Echinostoma spp. parasites. The prevalence of Echinostoma spp. sporocysts/rediae infection was not affected by increases in snail diversity, but significant negative correlations in metacercariae prevalence and intensity with snail diversity were observed. Additionally, varying effectiveness of the diluting hosts was found, i.e., snail species that were incompatible first intermediate hosts for Echinostoma spp. were more successful at diluting the echinostome parasites in the focal species, while H. trivolvis, a snail species that can harbor the first intermediate larval stages, amplified infection. These findings have important implications not only on the role of species diversity in reducing disease risk, but the success of the parasites in completing their life cycles and maintaining their abundance within an aquatic system.

  2. Cryptic species diversity reveals biogeographic support for the ‘mountain passes are higher in the tropics’ hypothesis

    PubMed Central

    Gill, B. A.; Kondratieff, B. C.; Casner, K. L.; Encalada, A. C.; Flecker, A. S.; Gannon, D. G.; Ghalambor, C. K.; Guayasamin, J. M.; Poff, N. L.; Simmons, M. P.; Thomas, S. A.; Zamudio, K. R.; Funk, W. C.

    2016-01-01

    The ‘mountain passes are higher in the tropics’ (MPHT) hypothesis posits that reduced climate variability at low latitudes should select for narrower thermal tolerances, lower dispersal and smaller elevational ranges compared with higher latitudes. These latitudinal differences could increase species richness at low latitudes, but that increase may be largely cryptic, because physiological and dispersal traits isolating populations might not correspond to morphological differences. Yet previous tests of the MPHT hypothesis have not addressed cryptic diversity. We use integrative taxonomy, combining morphology (6136 specimens) and DNA barcoding (1832 specimens) to compare the species richness, cryptic diversity and elevational ranges of mayflies (Ephemeroptera) in the Rocky Mountains (Colorado; approx. 40°N) and the Andes (Ecuador; approx. 0°). We find higher species richness and smaller elevational ranges in Ecuador than Colorado, but only after quantifying and accounting for cryptic diversity. The opposite pattern is found when comparing diversity based on morphology alone, underscoring the importance of uncovering cryptic species to understand global biodiversity patterns. PMID:27306051

  3. "Metamagnetoelectric" effect in multiferroics

    NASA Astrophysics Data System (ADS)

    Fouokeng, G. C.; Fodouop, F. Kuate; Tchoffo, M.; Fai, L. C.; Randrianantoandro, N.

    2018-05-01

    We present a theoretical calculation of magnetoelectric properties in a quasi-two dimensional spin chain externally controlled by a static electric field in y-direction and magnetic field in z-direction. Given the diversity of properties in functional materials and their applications in physics, the multiferroic model is investigated. By using the Fermi-Dirac statistics of quantum gases and the Landau theory, we assess the effects of the Dzyaloshinskii-Moriya interaction and the electric polarization on the magnetoelectric coupling that induces at low temperature the "metamagnetoelectric" effet, and likewise affects the ferroelectricity induced through symmetry mechanisms and magnetic properties of the multiferroic system. In fact, the variation of the induced polarisation due to spin arrangement through the Dzyaloshinskii-Moriya interaction gives rise to a multistep interdependent metamagnetic and metaelectric transitions which are settled up by the corresponding Dzyaloshinskii-Moriya parameter and the system then exhibits a spin gap that results from an electric and a magnetic demagnetization field range. This metamagnetoelectric effect observed in these multiferroic materials model is seem to be highly tunable via the external electric and magnetic fields and thus can be crucial in the design of new mechanisms for the processing and storage of data and other spintronic applications.

  4. The Specificity of Observational Studies in Physical Activity and Sports Sciences: Moving Forward in Mixed Methods Research and Proposals for Achieving Quantitative and Qualitative Symmetry.

    PubMed

    Anguera, M Teresa; Camerino, Oleguer; Castañer, Marta; Sánchez-Algarra, Pedro; Onwuegbuzie, Anthony J

    2017-01-01

    Mixed methods studies are been increasingly applied to a diversity of fields. In this paper, we discuss the growing use-and enormous potential-of mixed methods research in the field of sport and physical activity. A second aim is to contribute to strengthening the characteristics of mixed methods research by showing how systematic observation offers rigor within a flexible framework that can be applied to a wide range of situations. Observational methodology is characterized by high scientific rigor and flexibility throughout its different stages and allows the objective study of spontaneous behavior in natural settings, with no external influence. Mixed methods researchers need to take bold yet thoughtful decisions regarding both substantive and procedural issues. We present three fundamental and complementary ideas to guide researchers in this respect: we show why studies of sport and physical activity that use a mixed methods research approach should be included in the field of mixed methods research, we highlight the numerous possibilities offered by observational methodology in this field through the transformation of descriptive data into quantifiable code matrices, and we discuss possible solutions for achieving true integration of qualitative and quantitative findings.

  5. Accessible Earth: Enhancing diversity in the Geosciences through accessible course design

    NASA Astrophysics Data System (ADS)

    Bennett, R. A.; Lamb, D. A.

    2017-12-01

    The tradition of field-based instruction in the geoscience curriculum, which culminates in a capstone geological field camp, presents an insurmountable barrier to many disabled students who might otherwise choose to pursue geoscience careers. There is a widespread perception that success as a practicing geoscientist requires direct access to outcrops and vantage points available only to those able to traverse inaccessible terrain. Yet many modern geoscience activities are based on remotely sensed geophysical data, data analysis, and computation that take place entirely from within the laboratory. To challenge the perception of geoscience as a career option only for the non-disabled, we have created the capstone Accessible Earth Study Abroad Program, an alternative to geologic field camp for all students, with a focus on modern geophysical observation systems, computational thinking, data science, and professional development.In this presentation, we will review common pedagogical approaches in geosciences and current efforts to make the field more inclusive. We will review curricular access and inclusivity relative to a wide range of learners and provide examples of accessible course design based on our experiences in teaching a study abroad course in central Italy, and our plans for ongoing assessment, refinement, and dissemination of the effectiveness of our efforts.

  6. Promoting Cultural Diversity: African Music in Australian Teacher Education

    ERIC Educational Resources Information Center

    Joseph, Dawn

    2016-01-01

    Australia is forged by ongoing migration, welcoming a range of cultures, languages and ethnicities, celebrating a diverse range of the Arts. In this multicultural society, music and dance may serve as a positive medium to transmit and promote social cohesion. I argue that the inclusion of innovative and immersive practice of African music in…

  7. "Unthinkable" Selves: Identity Boundary Work in a Summer Field Ecology Enrichment Program for Diverse Youth

    ERIC Educational Resources Information Center

    Carlone, Heidi B.; Huffling, Lacey D.; Tomasek, Terry; Hegedus, Tess A.; Matthews, Catherine E.; Allen, Melony H.; Ash, Mary C.

    2015-01-01

    The historical under-representation of diverse youth in environmental science education is inextricably connected to access and identity-related issues. Many diverse youth with limited previous experience to the outdoors as a source for learning and/or leisure may consider environmental science as "unthinkable." This is an ethnographic…

  8. Science in the Mountains: A Unique Research Experience to Enhance Diversity in the Geosciences

    ERIC Educational Resources Information Center

    Hallar, A. Gannet; McCubbin, Ian B.; Hallar, Brittan; Levine, Roger; Stockwell, William R.; Lopez, Jimena P.; Wright, Jennifer M.

    2010-01-01

    Ethnic and racial minorities constitute an important part of the geosciences community because of their diverse perspectives and backgrounds. However, the geosciences have the poorest diversity record of all the science and engineering fields. Recruitment of minorities is important and numerous programs are focusing on engaging students in…

  9. Researching the Educational Benefits of Diversity. Research Report No. 2005-4

    ERIC Educational Resources Information Center

    Shaw, Emily J.

    2005-01-01

    There are many different ways to research the educational benefits of diversity. Most of the findings from the research in this field suggest that experiences with diversity in higher education result in significant benefits on learning and democracy outcomes. This paper offers several examples of previous studies, as well as recommendations and…

  10. Toward exploratory analysis of diversity unified across fields of study: an information visualization approach

    Treesearch

    Tuan Pham; Julia Jones; Ronald Metoyer; Frederick Colwell

    2014-01-01

    The study of the diversity of multivariate objects shares common characteristics and goals across disciplines, including ecology and organizational management. Nevertheless, subject-matter experts have adopted somewhat separate diversity concepts and analysis techniques, limiting the potential for sharing and comparing across disciplines. Moreover, while large and...

  11. Review of Gender and Racial Diversity in Radiation Protection.

    PubMed

    Gillenwalters, Elizabeth; Martinez, Nicole

    2017-04-01

    The rapidly changing demographics of the United States workforce include a large number of women and members of minority groups that are currently underrepresented in science and engineering-related education and careers. Recent research indicates that while singular incidents of sexism do exist, gender bias more often affects women in various subtle ways. The effects of stereotype threat and the lack of appropriate mentoring and female role models are samples of the possible factors contributing to performance and longevity for women in math-intensive fields. To address how this issue affects those in radiation protection, the current status of women in the field is reviewed as a progression through the scientific pipeline, from education and employment to positions in scientific bodies and professional recognition, with primary focus on American women and institutions. Racial diversity demographics are reviewed where available. Findings indicate women and minority racial groups are underrepresented in multiple aspects of education, research, and leadership. While gender diversity across the field has not yet reached gender parity, trending indicates that the percentage of women earning degrees in radiation protection has consistently increased over the last four decades. Diversity of racial groups, however, has remained fairly consistent and is well below national averages. Diverse perspectives have been documented in collective problem-solving to lead to more innovative solutions.

  12. Pollinator communities in strawberry crops - variation at multiple spatial scales.

    PubMed

    Ahrenfeldt, E J; Klatt, B K; Arildsen, J; Trandem, N; Andersson, G K S; Tscharntke, T; Smith, H G; Sigsgaard, L

    2015-08-01

    Predicting potential pollination services of wild bees in crops requires knowledge of their spatial distribution within fields. Field margins can serve as nesting and foraging habitats for wild bees and can be a source of pollinators. Regional differences in pollinator community composition may affect this spill-over of bees. We studied how regional and local differences affect the spatial distribution of wild bee species richness, activity-density and body size in crop fields. We sampled bees both from the field centre and at two different types of semi-natural field margins, grass strips and hedges, in 12 strawberry fields. The fields were distributed over four regions in Northern Europe, representing an almost 1100 km long north-south gradient. Even over this gradient, daytime temperatures during sampling did not differ significantly between regions and did therefore probably not impact bee activity. Bee species richness was higher in field margins compared with field centres independent of field size. However, there was no difference between centre and margin in body-size or activity-density. In contrast, bee activity-density increased towards the southern regions, whereas the mean body size increased towards the north. In conclusion, our study revealed a general pattern across European regions of bee diversity, but not activity-density, declining towards the field interior which suggests that the benefits of functional diversity of pollinators may be difficult to achieve through spill-over effects from margins to crop. We also identified dissimilar regional patterns in bee diversity and activity-density, which should be taken into account in conservation management.

  13. VisNAV 100: a robust, compact imaging sensor for enabling autonomous air-to-air refueling of aircraft and unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Katake, Anup; Choi, Heeyoul

    2010-01-01

    To enable autonomous air-to-refueling of manned and unmanned vehicles a robust high speed relative navigation sensor capable of proving high accuracy 3DOF information in diverse operating conditions is required. To help address this problem, StarVision Technologies Inc. has been developing a compact, high update rate (100Hz), wide field-of-view (90deg) direction and range estimation imaging sensor called VisNAV 100. The sensor is fully autonomous requiring no communication from the tanker aircraft and contains high reliability embedded avionics to provide range, azimuth, elevation (3 degrees of freedom solution 3DOF) and closing speed relative to the tanker aircraft. The sensor is capable of providing 3DOF with an error of 1% in range and 0.1deg in azimuth/elevation up to a range of 30m and 1 deg error in direction for ranges up to 200m at 100Hz update rates. In this paper we will discuss the algorithms that were developed in-house to enable robust beacon pattern detection, outlier rejection and 3DOF estimation in adverse conditions and present the results of several outdoor tests. Results from the long range single beacon detection tests will also be discussed.

  14. Diversity and Density: Lexically Determined Evaluative and Informational Consequences of Linguistic Complexity

    ERIC Educational Resources Information Center

    Bradac, James J.; And Others

    1977-01-01

    Defines lexical diversity as manifest vocabulary range and lexical density as the ratio of lexical to gramatical items in a unit of discourse. Examines the effects of lexical diversity and density on listeners' evaluative judgments. (MH)

  15. Pathways of nutrient loading and impacts on plant diversity in a New York peatland

    USGS Publications Warehouse

    Drexler, J.Z.; Bedford, B.L.

    2002-01-01

    Nutrient loading is a subtle, yet serious threat to the preservation of high diversity wetlands such as peatlands. Pathways of nutrient loading and impacts on plant diversity in a small peatland in New York State, USA were determined by collecting and analyzing a suite of hydrogeological, hydro-chemical, soil, and vegetation data. Piezometer clusters within an intensive network constituted hydro-chemical sampling points and focal points for randomly selected vegetation quadrats and soil-coring locations. Hydrogeological data and nutrient analyses showed that P and K loading occurred chiefly by means of overland flow from an adjacent farm field, whereas N loading occurred predominantly through ground-water flow from the farm field. Redundancy analysis and polynomial regression showed that nutrients, particularly total P in peat, total K in peat, extractable NH4-N, and NO3-N flux in ground water, were strongly negatively correlated with plant diversity measures at the site. No other environmental variables except vegetation measures associated with eutrophication demonstrated such a strong relationship with plant diversity. Nitrate loading over 4 mg m -2 day-1 was associated with low plant diversity, and Ca fluxes between 80 and 130 mg m-2 day-1 were associated with high plant diversity. Areas in the site with particularly low vascular plant and bryophyte species richness and Shannon-Wiener diversity (H') occurred adjacent to the farm field and near a hillside spring. High H' and species richness of vascular plants and bryophytes occurred in areas that were further removed from agriculture, contained no highly dominant vegetation, and were situated directly along the ground-water flow paths of springs. These areas were characterized by relatively constant water levels and consistent, yet moderate fluxes of base cations and nutrients. Overall, this study demonstrates that knowledge of site hydrogeology is crucial for determining potential pathways of nutrient loading and for developing relationships between nutrient inflows and wetland plant diversity. ?? 2002, The Society of Wetland Scientists.

  16. Portable Functional Neuroimaging as an Environmental Epidemiology Tool: A How-To Guide for the Use of fNIRS in Field Studies.

    PubMed

    Baker, Joseph M; Rojas-Valverde, Daniel; Gutiérrez, Randall; Winkler, Mirko; Fuhrimann, Samuel; Eskenazi, Brenda; Reiss, Allan L; Mora, Ana M

    2017-09-21

    The widespread application of functional neuroimaging within the field of environmental epidemiology has the potential to greatly enhance our understanding of how environmental toxicants affect brain function. Because many epidemiological studies take place in remote and frequently changing environments, it is necessary that the primary neuroimaging approach adopted by the epidemiology community be robust to many environments, easy to use, and, preferably, mobile. Here, we outline our use of functional near-infrared spectroscopy (fNIRS) to collect functional brain imaging data from Costa Rican farm workers enrolled in an epidemiological study on the health effects of chronic pesticide exposure. While couched in this perspective, we focus on the methodological considerations that are necessary to conduct a mobile fNIRS study in a diverse range of environments. Thus, this guide is intended to be generalizable to all research scenarios and projects in which fNIRS may be used to collect functional brain imaging data in epidemiological field surveys. https://doi.org/10.1289/EHP2049.

  17. Portable Functional Neuroimaging as an Environmental Epidemiology Tool: A How-To Guide for the Use of fNIRS in Field Studies

    PubMed Central

    Rojas-Valverde, Daniel; Gutiérrez, Randall; Winkler, Mirko; Fuhrimann, Samuel; Eskenazi, Brenda; Reiss, Allan L.; Mora, Ana M.

    2017-01-01

    Summary: The widespread application of functional neuroimaging within the field of environmental epidemiology has the potential to greatly enhance our understanding of how environmental toxicants affect brain function. Because many epidemiological studies take place in remote and frequently changing environments, it is necessary that the primary neuroimaging approach adopted by the epidemiology community be robust to many environments, easy to use, and, preferably, mobile. Here, we outline our use of functional near-infrared spectroscopy (fNIRS) to collect functional brain imaging data from Costa Rican farm workers enrolled in an epidemiological study on the health effects of chronic pesticide exposure. While couched in this perspective, we focus on the methodological considerations that are necessary to conduct a mobile fNIRS study in a diverse range of environments. Thus, this guide is intended to be generalizable to all research scenarios and projects in which fNIRS may be used to collect functional brain imaging data in epidemiological field surveys. https://doi.org/10.1289/EHP2049 PMID:28937962

  18. The scale invariant generator technique for quantifying anisotropic scale invariance

    NASA Astrophysics Data System (ADS)

    Lewis, G. M.; Lovejoy, S.; Schertzer, D.; Pecknold, S.

    1999-11-01

    Scale invariance is rapidly becoming a new paradigm for geophysics. However, little attention has been paid to the anisotropy that is invariably present in geophysical fields in the form of differential stratification and rotation, texture and morphology. In order to account for scaling anisotropy, the formalism of generalized scale invariance (GSI) was developed. Until now there has existed only a single fairly ad hoc GSI analysis technique valid for studying differential rotation. In this paper, we use a two-dimensional representation of the linear approximation to generalized scale invariance, to obtain a much improved technique for quantifying anisotropic scale invariance called the scale invariant generator technique (SIG). The accuracy of the technique is tested using anisotropic multifractal simulations and error estimates are provided for the geophysically relevant range of parameters. It is found that the technique yields reasonable estimates for simulations with a diversity of anisotropic and statistical characteristics. The scale invariant generator technique can profitably be applied to the scale invariant study of vertical/horizontal and space/time cross-sections of geophysical fields as well as to the study of the texture/morphology of fields.

  19. Experiences of Cultural Diversity in the Context of an Emergent Transnationalism

    ERIC Educational Resources Information Center

    Rizvi, Fazal

    2011-01-01

    In this article, the author argues that despite wide-ranging appeal of the discourses of globalization, our modes of thinking and ways of addressing issues of cultural diversity remain trapped within a national framework. The dominant constructions of cultural diversity often overlook the ways in which experiences of diversity now take place in…

  20. Workforce diversity in outpatient substance abuse treatment: the role of leaders' characteristics.

    PubMed

    Guerrero, Erick G

    2013-02-01

    Although the outpatient substance abuse treatment field has seen an increase in referrals of African American and Latino clients, there have been limited changes in the diversity of the workforce. This discordance may exacerbate treatment disparities experienced by these clients. Program leaders have significant influence to leverage resources to develop staff diversity. Analysis of panel data from 1995 to 2005 showed that the most significant predictors of diversity were the characteristics of leaders. In particular, programs with managers with racially and ethnically concordant backgrounds and their education level were positively related to the percentage of Latino and African American staff. A high percentage of African American staff was positively associated with managers' tenure, but inversely related to licensed directors. Diversification of the field has increased, yet efforts have not matched increases in client diversity. Implications for health care reform legislation seeking to improve cultural competence through diversification of the workforce are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Population genetic signatures of a climate change driven marine range extension.

    PubMed

    Ramos, Jorge E; Pecl, Gretta T; Moltschaniwskyj, Natalie A; Semmens, Jayson M; Souza, Carla A; Strugnell, Jan M

    2018-06-22

    Shifts in species distribution, or 'range shifts', are one of the most commonly documented responses to ocean warming, with important consequences for the function and structure of ecosystems, and for socio-economic activities. Understanding the genetic signatures of range shifts can help build our knowledge of the capacity of species to establish and persist in colonised areas. Here, seven microsatellite loci were used to examine the population connectivity, genetic structure and diversity of Octopus tetricus, which has extended its distribution several hundred kilometres polewards associated with the southwards extension of the warm East Australian Current along south-eastern Australia. The historical distribution and the range extension zones had significant genetic differences but levels of genetic diversity were comparable. The population in the range extension zone was sub-structured, contained relatively high levels of self-recruitment and was sourced by migrants from along the entire geographic distribution. Genetic bottlenecks and changes in population size were detected throughout the range extension axis. Persistent gene flow from throughout the historical zone and moderate genetic diversity may buffer the genetic bottlenecks and favour the range extension of O. tetricus. These characteristics may aid adaptation, establishment, and long-term persistence of the population in the range extension zone.

  2. Ethnic diversity and employment growth in English cities.

    PubMed

    Lee, Neil

    2011-01-01

    There are many reasons why cities with diverse populations may grow faster. Ethnic diversity might attract human capital, tourists or firms, increase productivity through diverse approaches to problem-solving or ethnic minority entrepreneurship. Yet there are also reasons to believe that diversity could be harmful, by leading to sub-optimal provision of public goods or reducing trust or social capital. Or it may be irrelevant, being merely a proxy for class. A number of studies have shown both positive and negative relationships between diversity and growth, using a range of different measures for "diversity." This paper asks two questions: have more diverse English cities grown faster? And does measurement matter: is it important to have a multinational population or an ethnically diverse one? To answer these questions, in this paper a range of models are estimated for employment growth for 53 English cities between 1981 and 2001. The evidence suggests that cities with a high proportion of their populations born abroad in 1981 grew faster in the subsequent 10 years. Neither diversity by country of birth nor ethnic diversity is significant in the period 1991-2001. However, when variables accounting for both are included together, it appears that cities with a large number of migrants saw higher employment growth in the 1990s, but that ethnically diverse cities were less successful. The results presented here suggest that considerable attention needs to be paid to the variable used to indicate "diversity" in these studies and that the impact of diversity varies according to nature of the groups any indicator for "diversity" is representing.

  3. Diversity in the dermatology workforce.

    PubMed

    Hinojosa, Jorge A; Pandya, Amit G

    2016-12-01

    The United States is becoming increasingly diverse, and minorities are projected to represent the majority of our population in the near future. Unfortunately, health disparities still exist for these groups, and inequalities have also become evident in the field of dermatology. There is currently a lack of diversity within the dermatology workforce. Potential solutions to these health care disparities include increasing cultural competence for all physicians and improving diversity in the dermatology workforce. ©2016 Frontline Medical Communications.

  4. Phenotype diversity analysis of red-grained rice landraces from Yuanyang Hani's terraced fields, China

    NASA Astrophysics Data System (ADS)

    Li, Lianjie; Cheng, Long

    2017-10-01

    There are many areas in the world have terraced fields, Yuanyang Rani's terraced fields are examples in the world, and their unique ecological diversity is beyond other terraced fields, rice landraces are very rich. In order to provide useful information for protection and utilization of red-grained rice landraces from Rani's terraced fields, 61 red-grained rice landraces were assessed based 20 quantitative traits. Principal component analysis (PCA) suggested that 20 quantitative characters could be simplified to seven principal components, and their accumulative contribution ration amounted to 78.699%. The first principal component (PC1) explained 18.375% of the total variance, which was contributed by filled grain number, 1000-grain weight, spikelets per panicle, secondary branch number, grain length, and grain thickness. PC2 accounted for 16.548% of the variance and featured flag leaf width, flag leaf area, panicle neck length and primary branch number. These traits were the most effective parameters to discriminate individuals. At the request of the proceedings editor and with the approval of all authors, article 040111 titled, "Phenotype diversity analysis of red-grained rice landraces from Yuanyang Hani's terraced fields, China," is being retracted from the public record due to the fact that it is a duplication of article 040110 published in the same volume.

  5. Characterizing fire-related spatial patterns in fire-prone ecosystems using optical and microwave remote sensing

    NASA Astrophysics Data System (ADS)

    Henry, Mary Catherine

    The use of active and passive remote sensing systems for relating forest spatial patterns to fire history was tested over one of the Arizona Sky Islands. Using Landsat Thematic Mapper (TM), Shuttle Imaging Radar (SIR-C), and data fusion I examined the relationship between landscape metrics and a range of fire history characteristics. Each data type (TM, SIR-C, and fused) was processed in the following manner: each band, channel, or derived feature was simplified to a thematic layer and landscape statistics were calculated for plots with known fire history. These landscape metrics were then correlated with fire history characteristics, including number of fire-free years in a given time period, mean fire-free interval, and time since fire. Results from all three case studies showed significant relationships between fire history and forest spatial patterns. Data fusion performed as well or better than Landsat TM alone, and better than SIR-C alone. These comparisons were based on number and strength of significant correlations each method achieved. The landscape metric that was most consistent and obtained the greatest number of significant correlations was Shannon's Diversity Index. Results also agreed with field-based research that has linked higher fire frequency to increased landscape diversity and patchiness. An additional finding was that the fused data seem to detect fire-related spatial patterns over a range of scales.

  6. Genetic Status and Timing of a Weevil Introduction to Santa Cruz Island, Galápagos

    PubMed Central

    2014-01-01

    Successful invasive species can overcome or circumvent the potential genetic loss caused by an introduction bottleneck through a rapid population expansion and admixture from multiple introductions. We explore the genetic makeup and the timing of a species introduction to Santa Cruz Island in the Galápagos archipelago. We investigate the presence of processes that can maintain genetic diversity in populations of the broad-nosed weevil Galapaganus howdenae howdenae. Analyses of combined genotypes for 8 microsatellite loci showed evidence of past population size reductions through moment and likelihood-based estimators. No evidence of admixture through multiple introductions was found, but substantial current population sizes (N0 298, 95% credible limits 50–2300), genetic diversity comparable with long-established endemics (Mean number of alleles = 3.875), and lack of genetic structure across the introduced range (F ST = 0.01359) could suggest that foundations are in place for populations to rapidly recover any loss of genetic variability. The time estimates for the introduction into Santa Cruz support an accidental transfer during the colonization period (1832–1959) predating the spurt in human population growth. Our evaluation of the genetic status of G. h. howdenae suggests potential for population growth in addition to our field observations of a concurrent expansion in range and feeding preferences towards protected areas and endemic host plants. PMID:24399746

  7. Increasing Diversity in Computer Science: Acknowledging, yet Moving Beyond, Gender

    NASA Astrophysics Data System (ADS)

    Larsen, Elizabeth A.; Stubbs, Margaret L.

    Lack of diversity within the computer science field has, thus far, been examined most fully through the lens of gender. This article is based on a follow-on to Margolis and Fisher's (2002) study and includes interviews with 33 Carnegie Mellon University students from the undergraduate senior class of 2002 in the School of Computer Science. We found evidence of similarities among the perceptions of these women and men on definitions of computer science, explanations for the notoriously low proportion of women in the field, characterizations of a typical computer science student, impressions of recent curricular changes, a sense of the atmosphere/culture in the program, views of the Women@SCS campus organization, and suggestions for attracting and retaining well-rounded students in computer science. We conclude that efforts to increase diversity in the computer science field will benefit from a more broad-based approach that considers, but is not limited to, notions of gender difference.

  8. Building a more diverse biomedical engineering workforce: Biomedical engineering at the university of the district of Columbia, a historically black college & university.

    PubMed

    Thompson, Lara A; Adebayo, A Segun; Nian Zhang; Haghani, Sasan; Dowell, Kathleen; Shetty, Devdas

    2016-08-01

    Biomedical Engineering (BME) is a new, multidisciplinary, and rapidly growing field, however, the BME Workforce suffers from limited ethnic and gender diversity. Despite the demand and growth of this new field due to its public health importance, only 4 out of the 107 Historically Black Colleges and Universities (HBCUs) nationwide offers a Bachelor's of Science (B.S.) in Bio-Engineering related fields. In order to contribute to a growing BME Workforce, HBCUs need to react and offer more degree-programs relevant to BME. At the University of the District of Columbia (UDC), an HBCU and the District's only public institution for higher learning, we have recently established a new, degree program: Bachelor of Science in Biomedical Engineering (B.S. in BME) full-board approved in Fall 2014, with program activities initiated in Fall 2015. The educational goal of this program is to enhance the quality and diversity of the BME Workforce via student professional development, new and relevant BME courses, and BME scholarly activities (e.g., guest lectures and journal club sessions), ultimately to increase the number of ethnic minorities pursuing careers and degrees in BME. Through our program activities, we are aiming to meet the nation's demand to contribute to a diverse BME workforce, directed towards solving problems in human health. A secondary, but related goal, is to increase the diversity of STEM-related fields. This paper summarizes our initial, but encouraging, BME activity-related findings. However, this study will be longitudinal (on a multiple year time period) to observe the true outcomes of our initiative.

  9. Diversity and functional traits of culturable microbiome members, including cyanobacteria in the rice phyllosphere.

    PubMed

    Venkatachalam, S; Ranjan, K; Prasanna, R; Ramakrishnan, B; Thapa, S; Kanchan, A

    2016-07-01

    The diversity and abundance of culturable microbiome members of the rice phyllosphere was investigated using cv. Pusa Punjab Basmati 1509. Both diversity and species richness of bacteria were significantly higher in plants in pots in a semi-controlled environment than those in fields. Application of fertilisers reduced both diversity and species richness in field-grown plants under a conventional flooded system of rice intensification (SRI) and in dry-seeded rice (DSR) modes. Sequence analyses of 16S rDNA of culturable bacteria, those selected after amplified ribosomal DNA restriction analysis (ARDRA), showed the dominance of α-proteobacteria (35%) and actinobacteria (38%); Pantoea, Exiguobacterium and Bacillus were common among the culturable phyllospheric bacteria. About 34% of 83 culturable bacterial isolates had higher potential (>2 μg·ml(-1) ) for indole acetic acid production in the absence of tryptophan. Interestingly, the phyllosphere bacterial isolates from the pot experiment had significantly higher potential for nitrogen fixation than isolates from the field experiment. Enrichment for cyanobacteria showed both unicellular forms and non-heterocystous filaments under aerobic as well as anaerobic conditions. PCR-DGGE analysis of these showed that aerobic and anaerobic conditions as well as the three modes of cultivation of rice in the field strongly influenced the number and abundance of phylotypes. The adaptability and functional traits of these culturable microbiome members suggest enormous diversity in the phyllosphere, including potential for plant growth promotion, which was also significantly influenced by the different methods of growing rice. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  10. Local Diversity and Fine-Scale Organization of Receptive Fields in Mouse Visual Cortex

    PubMed Central

    Histed, Mark H.; Yurgenson, Sergey

    2011-01-01

    Many thousands of cortical neurons are activated by any single sensory stimulus, but the organization of these populations is poorly understood. For example, are neurons in mouse visual cortex—whose preferred orientations are arranged randomly—organized with respect to other response properties? Using high-speed in vivo two-photon calcium imaging, we characterized the receptive fields of up to 100 excitatory and inhibitory neurons in a 200 μm imaged plane. Inhibitory neurons had nonlinearly summating, complex-like receptive fields and were weakly tuned for orientation. Excitatory neurons had linear, simple receptive fields that can be studied with noise stimuli and system identification methods. We developed a wavelet stimulus that evoked rich population responses and yielded the detailed spatial receptive fields of most excitatory neurons in a plane. Receptive fields and visual responses were locally highly diverse, with nearby neurons having largely dissimilar receptive fields and response time courses. Receptive-field diversity was consistent with a nearly random sampling of orientation, spatial phase, and retinotopic position. Retinotopic positions varied locally on average by approximately half the receptive-field size. Nonetheless, the retinotopic progression across the cortex could be demonstrated at the scale of 100 μm, with a magnification of ∼10 μm/°. Receptive-field and response similarity were in register, decreasing by 50% over a distance of 200 μm. Together, the results indicate considerable randomness in local populations of mouse visual cortical neurons, with retinotopy as the principal source of organization at the scale of hundreds of micrometers. PMID:22171051

  11. Landscape-level patterns of avian diversity in the Oregon Coast Range

    Treesearch

    Samuel A. Cushman; Kevin McGarigal

    2003-01-01

    We used a comparative mensurative landscape-level experiment to quantify the relative importance of mature forest area and fragmentation and differences among watersheds in influencing avian community diversity in the Oregon Coast Range, USA. Our study design included three large hydrological basins, two levels of fragmentation, and six levels of mature forest area. We...

  12. Morphological basis for the evolution of acoustic diversity in oscine songbirds.

    PubMed

    Riede, Tobias; Goller, Franz

    2014-03-22

    Acoustic properties of vocalizations arise through the interplay of neural control with the morphology and biomechanics of the sound generating organ, but in songbirds it is assumed that the main driver of acoustic diversity is variation in telencephalic motor control. Here we show, however, that variation in the composition of the vibrating tissues, the labia, underlies diversity in one acoustic parameter, fundamental frequency (F0) range. Lateral asymmetry and arrangement of fibrous proteins in the labia into distinct layers is correlated with expanded F0 range of species. The composition of the vibrating tissues thus represents an important morphological foundation for the generation of a broad F0 range, indicating that morphological specialization lays the foundation for the evolution of complex acoustic repertoires.

  13. Contrasting beneficial and pathogenic microbial communities across consecutive cropping fields of greenhouse strawberry.

    PubMed

    Huang, Ying; Xiao, Xu; Huang, Hongying; Jing, Jinquan; Zhao, Hejuan; Wang, Lin; Long, Xi-En

    2018-04-27

    Soil weakness across consecutive cropping fields can be partially explained by the changes in microbial community diversity and structure. Succession patterns and co-occurrence mechanisms of bacteria and fungi, especially beneficial or pathogenic memberships in continuous cropping strawberry fields and their response to edaphic factors remained unclear. In this study, Illumina sequencing of bacterial 16S ribosomal RNA and fungal internal transcribed spacer genes was applied in three time-course (1, 5, and 10 years) fields across spring and winter. Results showed that the richness and diversity of bacterial and fungal communities increased significantly (p < 0.05) in 1-year field and decreased afterwards across two seasons. Network analysis revealed beneficial bacterial and fungal genus (Bacillus and Trichoderma) dominated under 1-year field whereas Fusarium accumulated under 10-year field at either season. Moreover, Trichoderma harzianum and Bacillus subtilis that have been reported to effectively control Fusarium wilt in strawberries accumulated significantly under 1-year field. Canonical correspondence analysis showed that beneficial bacterial Rhodospirillales and Rhizobiales and fungal Glomerales accumulated in 1-year field and their distributions were significantly affected by soil pH, microbial biomass C (MBC), and moisture. On the contrary, fungal pathogenic species Fusarium oxysporum strongly increased under 10-year field at the winter sample and the abundance was positively (p < 0.01) correlated with soil moisture. Our study suggested that the potential of microcosm under 1-year field stimulates the whole microbial diversity and favors different beneficial taxa across two seasons. Soil pH, moisture, and MBC were the most important edaphic factors leading to contrasting beneficial and pathogenic memberships across consecutive strawberry cropping fields.

  14. Organic farming favours insect-pollinated over non-insect pollinated forbs in meadows and wheat fields.

    PubMed

    Batáry, Péter; Sutcliffe, Laura; Dormann, Carsten F; Tscharntke, Teja

    2013-01-01

    The aim of this study was to determine the relative effects of landscape-scale management intensity, local management intensity and edge effect on diversity patterns of insect-pollinated vs. non-insect pollinated forbs in meadows and wheat fields. Nine landscapes were selected differing in percent intensively used agricultural area (IAA), each with a pair of organic and conventional winter wheat fields and a pair of organic and conventional meadows. Within fields, forbs were surveyed at the edge and in the interior. Both diversity and cover of forbs were positively affected by organic management in meadows and wheat fields. This effect, however, differed significantly between pollination types for species richness in both agroecosystem types (i.e. wheat fields and meadows) and for cover in meadows. Thus, we show for the first time in a comprehensive analysis that insect-pollinated plants benefit more from organic management than non-insect pollinated plants regardless of agroecosystem type and landscape complexity. These benefits were more pronounced in meadows than wheat fields. Finally, the community composition of insect-pollinated and non-insect-pollinated forbs differed considerably between management types. In summary, our findings in both agroecosystem types indicate that organic management generally supports a higher species richness and cover of insect-pollinated plants, which is likely to be favourable for the density and diversity of bees and other pollinators.

  15. Organic Farming Favours Insect-Pollinated over Non-Insect Pollinated Forbs in Meadows and Wheat Fields

    PubMed Central

    Batáry, Péter; Sutcliffe, Laura; Dormann, Carsten F.; Tscharntke, Teja

    2013-01-01

    The aim of this study was to determine the relative effects of landscape-scale management intensity, local management intensity and edge effect on diversity patterns of insect-pollinated vs. non-insect pollinated forbs in meadows and wheat fields. Nine landscapes were selected differing in percent intensively used agricultural area (IAA), each with a pair of organic and conventional winter wheat fields and a pair of organic and conventional meadows. Within fields, forbs were surveyed at the edge and in the interior. Both diversity and cover of forbs were positively affected by organic management in meadows and wheat fields. This effect, however, differed significantly between pollination types for species richness in both agroecosystem types (i.e. wheat fields and meadows) and for cover in meadows. Thus, we show for the first time in a comprehensive analysis that insect-pollinated plants benefit more from organic management than non-insect pollinated plants regardless of agroecosystem type and landscape complexity. These benefits were more pronounced in meadows than wheat fields. Finally, the community composition of insect-pollinated and non-insect-pollinated forbs differed considerably between management types. In summary, our findings in both agroecosystem types indicate that organic management generally supports a higher species richness and cover of insect-pollinated plants, which is likely to be favourable for the density and diversity of bees and other pollinators. PMID:23382979

  16. Diversity and stability in Mississippi stream fish assemblages

    Treesearch

    Jocob F. Schaefer; Scott R. Clark; Melvin L. Jr. Warren

    2012-01-01

    Positive correlations between diversity and stability have been reported for a number of ecosystems and are thought to be caused by a stabilizing effect of differential species’ responses to environmental perturbation. Empirical field studies in which investigators tested for diversity–stability relationships are lacking for some taxonomic groups and typically have not...

  17. An Exercise to Demonstrate Soil Microbial Diversity in Introductory Environmental Science Classrooms

    ERIC Educational Resources Information Center

    Yarwood, Stephanie A.; Sulzman, Elizabeth W.

    2008-01-01

    High diversity of microorganisms in the soil matrix has been the focus of extensive research in the fields of soil biology and microbial ecology, and is a key concept that students in the environmental or biological sciences should understand. Two activities to demonstrate diversity and highlight the challenges faced in studying soil microbial…

  18. The Diversity of Cultural Participation: Findings from a National Survey. Building Arts Participation: New Findings from the Field

    ERIC Educational Resources Information Center

    Ostrower, Francie

    2005-01-01

    This survey represents a preliminary step toward demonstrating the diversity of motivations and circumstances that characterize cultural participation. This report examines only live attendance. The evidence presented in this report indicates the pressing need for additional analyses that make diversity a central facet of examining other…

  19. The `Strawberry Volcanic Field' of Northeastern Oregon: Another Piece of the CRB Puzzle?

    NASA Astrophysics Data System (ADS)

    Steiner, A. R.; Streck, M. J.

    2010-12-01

    The Mid to Late Miocene Strawberry Volcanics field (SVF) located along the southern margin of the John Day valley of NE Oregon, comprise a diverse group of volcanic rocks ranging from basalt to rhyolite. The main outcrop area of the SVF (3,400 km2) is bordered by units from the Columbia River Basalt Group (CRBG), with the main CRB units to the north, the Picture Gorge Basalt to the east and Steens Basalt to the south. The geographic position and age of the Strawberry Volcanics make a genetic relationship to CRB volcanism likely, yet little is known about this diverse volcanic field. This research aims at refining the stratigraphic and age relationships as well as the petrology and geochemistry of magmas associated with the SVF. Previous investigations (e.g. Robyn, 1977) found that the SVF was active between 20 to 10 Ma with the main pulse largely being coeval with the 15 Ma CRBG eruptions. Lavas and tuffs from the SVF are calc-alkaline with low FeO*/MgO (~ 2.56 wt. %), high Al2O3 (~ 16.4 wt. %), low TiO2 (~ 1.12 wt.%), and span the entire compositional range from basalt to rhyolite (47-78 wt. % SiO2) with andesite as the dominant lithology. Basaltic lavas from the SVF have compositional affinities to earlier Steens Basalt, and some trace element concentrations and ratios are indistinguishable from those of CRBG lavas (e.g. Zr, Ba, Sr, and Ce/Y). Andesites are calc-alkaline, but contrary to typical arc (orogenic) andesites, SVF andesites are exceedingly phenocryst poor (<3% phenocrysts with microphenocrysts of plagioclase and lesser pyroxene which occasionally occur in crystal clots instead of single crystals). In addition, some lavas (basaltic-intermediate) are phenocryst-rich (~25%), containing plagioclase, olivine, opx, and cpx. However, phenocrysts in these lavas are strongly zoned and resorbed, and in general, these lavas are volumetrically insignificant compared with the phenocrysts poor andesites. Rhyolitic lavas are also phenocryst poor (< 3%) and appear to be most voluminous in the southwestern portion of the field area from Bear Valley to Logan Valley. Our preliminary interpretation is that the Strawberry Volcanics are largely the product of hot-spot related basaltic magmas interacting with the continental crust. The range in compositions from calc-alkaline andesite to rhyolite may be attributed to the hybridization of mantle-derived and crustal melts, with the more evolved compositions reflecting greater proportions of crustally derived material and/or higher degrees of differentiation. Furthermore, since the earliest SVF eruption is 3 Ma older than the proposed onset of the CRBG (~ 17 Ma Steens Basalt), if the SVF is chemically related to the CRBG then the timing and location of the initiation of the CRBG will need to be reassessed.

  20. Diversity and host range of foliar fungal endophytes: are tropical leaves biodiversity hotspots?

    PubMed

    Arnold, A Elizabeth; Lutzoni, F

    2007-03-01

    Fungal endophytes are found in asymptomatic photosynthetic tissues of all major lineages of land plants. The ubiquity of these cryptic symbionts is clear, but the scale of their diversity, host range, and geographic distributions are unknown. To explore the putative hyperdiversity of tropical leaf endophytes, we compared endophyte communities along a broad latitudinal gradient from the Canadian arctic to the lowland tropical forest of central Panama. Here, we use molecular sequence data from 1403 endophyte strains to show that endophytes increase in incidence, diversity, and host breadth from arctic to tropical sites. Endophyte communities from higher latitudes are characterized by relatively few species from many different classes of Ascomycota, whereas tropical endophyte assemblages are dominated by a small number of classes with a very large number of endophytic species. The most easily cultivated endophytes from tropical plants have wide host ranges, but communities are dominated by a large number of rare species whose host range is unclear. Even when only the most easily cultured species are considered, leaves of tropical trees represent hotspots of fungal species diversity, containing numerous species not yet recovered from other biomes. The challenge remains to recover and identify those elusive and rarely cultured taxa with narrower host ranges, and to elucidate the ecological roles of these little-known symbionts in tropical forests.

  1. Discovering Diversity.

    ERIC Educational Resources Information Center

    Manner, Barbara M.; Hattler, Jean Anne

    2000-01-01

    Introduces a preservice teacher field trip to the rain forests and coastal areas. This experience develops an awareness for different cultures among preservice teachers by experiencing biological and cultural diversity in Costa Rica. Presents students' own ideas on this experience. (YDS)

  2. On the uses of diversity.

    PubMed Central

    Bishop, D

    1976-01-01

    An examination is made of the uses of diversity in medical library activities and personnel. This concept is extended also to the broader field of librarianship and to some forecasts of future directions for medical libraries. PMID:974292

  3. Multitarget, quantitative nanoplasmonic electrical field-enhanced resonating device (NE2RD) for diagnostics.

    PubMed

    Inci, Fatih; Filippini, Chiara; Baday, Murat; Ozen, Mehmet Ozgun; Calamak, Semih; Durmus, Naside Gozde; Wang, ShuQi; Hanhauser, Emily; Hobbs, Kristen S; Juillard, Franceline; Kuang, Ping Ping; Vetter, Michael L; Carocci, Margot; Yamamoto, Hidemi S; Takagi, Yuko; Yildiz, Umit Hakan; Akin, Demir; Wesemann, Duane R; Singhal, Amit; Yang, Priscilla L; Nibert, Max L; Fichorova, Raina N; Lau, Daryl T-Y; Henrich, Timothy J; Kaye, Kenneth M; Schachter, Steven C; Kuritzkes, Daniel R; Steinmetz, Lars M; Gambhir, Sanjiv S; Davis, Ronald W; Demirci, Utkan

    2015-08-11

    Recent advances in biosensing technologies present great potential for medical diagnostics, thus improving clinical decisions. However, creating a label-free general sensing platform capable of detecting multiple biotargets in various clinical specimens over a wide dynamic range, without lengthy sample-processing steps, remains a considerable challenge. In practice, these barriers prevent broad applications in clinics and at patients' homes. Here, we demonstrate the nanoplasmonic electrical field-enhanced resonating device (NE(2)RD), which addresses all these impediments on a single platform. The NE(2)RD employs an immunodetection assay to capture biotargets, and precisely measures spectral color changes by their wavelength and extinction intensity shifts in nanoparticles without prior sample labeling or preprocessing. We present through multiple examples, a label-free, quantitative, portable, multitarget platform by rapidly detecting various protein biomarkers, drugs, protein allergens, bacteria, eukaryotic cells, and distinct viruses. The linear dynamic range of NE(2)RD is five orders of magnitude broader than ELISA, with a sensitivity down to 400 fg/mL This range and sensitivity are achieved by self-assembling gold nanoparticles to generate hot spots on a 3D-oriented substrate for ultrasensitive measurements. We demonstrate that this precise platform handles multiple clinical samples such as whole blood, serum, and saliva without sample preprocessing under diverse conditions of temperature, pH, and ionic strength. The NE(2)RD's broad dynamic range, detection limit, and portability integrated with a disposable fluidic chip have broad applications, potentially enabling the transition toward precision medicine at the point-of-care or primary care settings and at patients' homes.

  4. Multitarget, quantitative nanoplasmonic electrical field-enhanced resonating device (NE2RD) for diagnostics

    PubMed Central

    Inci, Fatih; Filippini, Chiara; Ozen, Mehmet Ozgun; Calamak, Semih; Durmus, Naside Gozde; Wang, ShuQi; Hanhauser, Emily; Hobbs, Kristen S.; Juillard, Franceline; Kuang, Ping Ping; Vetter, Michael L.; Carocci, Margot; Yamamoto, Hidemi S.; Takagi, Yuko; Yildiz, Umit Hakan; Akin, Demir; Wesemann, Duane R.; Singhal, Amit; Yang, Priscilla L.; Nibert, Max L.; Fichorova, Raina N.; Lau, Daryl T.-Y.; Henrich, Timothy J.; Kaye, Kenneth M.; Schachter, Steven C.; Kuritzkes, Daniel R.; Steinmetz, Lars M.; Gambhir, Sanjiv S.; Davis, Ronald W.; Demirci, Utkan

    2015-01-01

    Recent advances in biosensing technologies present great potential for medical diagnostics, thus improving clinical decisions. However, creating a label-free general sensing platform capable of detecting multiple biotargets in various clinical specimens over a wide dynamic range, without lengthy sample-processing steps, remains a considerable challenge. In practice, these barriers prevent broad applications in clinics and at patients’ homes. Here, we demonstrate the nanoplasmonic electrical field-enhanced resonating device (NE2RD), which addresses all these impediments on a single platform. The NE2RD employs an immunodetection assay to capture biotargets, and precisely measures spectral color changes by their wavelength and extinction intensity shifts in nanoparticles without prior sample labeling or preprocessing. We present through multiple examples, a label-free, quantitative, portable, multitarget platform by rapidly detecting various protein biomarkers, drugs, protein allergens, bacteria, eukaryotic cells, and distinct viruses. The linear dynamic range of NE2RD is five orders of magnitude broader than ELISA, with a sensitivity down to 400 fg/mL This range and sensitivity are achieved by self-assembling gold nanoparticles to generate hot spots on a 3D-oriented substrate for ultrasensitive measurements. We demonstrate that this precise platform handles multiple clinical samples such as whole blood, serum, and saliva without sample preprocessing under diverse conditions of temperature, pH, and ionic strength. The NE2RD’s broad dynamic range, detection limit, and portability integrated with a disposable fluidic chip have broad applications, potentially enabling the transition toward precision medicine at the point-of-care or primary care settings and at patients’ homes. PMID:26195743

  5. Two colonisation stages generate two different patterns of genetic diversity within native and invasive ranges of Ulex europaeus

    PubMed Central

    Hornoy, B; Atlan, A; Roussel, V; Buckley, Y M; Tarayre, M

    2013-01-01

    Genetic diversity and the way a species is introduced influence the capacity of populations of invasive species to persist in, and adapt to, their new environment. The diversity of introduced populations affects their evolutionary potential, which is particularly important for species that have invaded a wide range of habitats and climates, such as European gorse, Ulex europaeus. This species originated in the Iberian peninsula and colonised Europe in the Neolithic; over the course of the past two centuries it was introduced to, and has become invasive in, other continents. We characterised neutral genetic diversity and its structure in the native range and in invaded regions. By coupling these results with historical data, we have identified the way in which gorse populations were introduced and the consequences of introduction history on genetic diversity. Our study is based on the genotyping of individuals from 18 populations at six microsatellite loci. As U. europaeus is an allohexaploid species, we used recently developed tools that take into account genotypic ambiguity. Our results show that genetic diversity in gorse is very high and mainly contained within populations. We confirm that colonisation occurred in two stages. During the first stage, gorse spread out naturally from Spain towards northern Europe, losing some genetic diversity. During the second stage, gorse was introduced by humans into different regions of the world, from northern Europe. These introductions resulted in the loss of rare alleles but did not significantly reduce genetic diversity and thus the evolutionary potential of this invasive species. PMID:23759725

  6. Two colonisation stages generate two different patterns of genetic diversity within native and invasive ranges of Ulex europaeus.

    PubMed

    Hornoy, B; Atlan, A; Roussel, V; Buckley, Y M; Tarayre, M

    2013-11-01

    Genetic diversity and the way a species is introduced influence the capacity of populations of invasive species to persist in, and adapt to, their new environment. The diversity of introduced populations affects their evolutionary potential, which is particularly important for species that have invaded a wide range of habitats and climates, such as European gorse, Ulex europaeus. This species originated in the Iberian peninsula and colonised Europe in the Neolithic; over the course of the past two centuries it was introduced to, and has become invasive in, other continents. We characterised neutral genetic diversity and its structure in the native range and in invaded regions. By coupling these results with historical data, we have identified the way in which gorse populations were introduced and the consequences of introduction history on genetic diversity. Our study is based on the genotyping of individuals from 18 populations at six microsatellite loci. As U. europaeus is an allohexaploid species, we used recently developed tools that take into account genotypic ambiguity. Our results show that genetic diversity in gorse is very high and mainly contained within populations. We confirm that colonisation occurred in two stages. During the first stage, gorse spread out naturally from Spain towards northern Europe, losing some genetic diversity. During the second stage, gorse was introduced by humans into different regions of the world, from northern Europe. These introductions resulted in the loss of rare alleles but did not significantly reduce genetic diversity and thus the evolutionary potential of this invasive species.

  7. The meaning, the sense and the significance: translating the science of mesenchymal stem cells into medicine.

    PubMed

    Bianco, Paolo; Cao, Xu; Frenette, Paul S; Mao, Jeremy J; Robey, Pamela G; Simmons, Paul J; Wang, Cun-Yu

    2013-01-01

    Mesenchymal stem cells (MSCs) are the focus of intensive efforts worldwide directed not only at elucidating their nature and unique properties but also developing cell-based therapies for a diverse range of diseases. More than three decades have passed since the original formulation of the concept, revolutionary at the time, that multiple connective tissues could emanate from a common progenitor or stem cell retained in the postnatal bone marrow. Despite the many important advances made since that time, substantial ambiguities still plague the field regarding the nature, identity, function, mode of isolation and experimental handling of MSCs. These uncertainties have a major impact on their envisioned therapeutic use.

  8. Liquid crystalline tactoids: ordered structure, defective coalescence and evolution in confined geometries

    NASA Astrophysics Data System (ADS)

    Wang, Pei-Xi; MacLachlan, Mark J.

    2017-12-01

    Tactoids are liquid crystalline microdroplets that spontaneously nucleate from isotropic dispersions, and transform into macroscopic anisotropic phases. These intermediate structures have been found in a range of molecular, polymeric and colloidal liquid crystals. Typically only studied by polarized optical microscopy, these ordered but easily deformable microdroplets are now emerging as interesting components for structural investigations and developing new materials. In this review, we highlight the structure, property and transformation of tactoids in different compositions, but especially cellulose nanocrystals. We have selected references that illustrate the diversity and most exciting developments in tactoid research, while capturing the historical development of this field. This article is part of a discussion meeting issue `New horizons for cellulose nanotechnology'.

  9. Dynamic Skin Patterns in Cephalopods

    PubMed Central

    How, Martin J.; Norman, Mark D.; Finn, Julian; Chung, Wen-Sung; Marshall, N. Justin

    2017-01-01

    Cephalopods are unrivaled in the natural world in their ability to alter their visual appearance. These mollusks have evolved a complex system of dermal units under neural, hormonal, and muscular control to produce an astonishing variety of body patterns. With parallels to the pixels on a television screen, cephalopod chromatophores can be coordinated to produce dramatic, dynamic, and rhythmic displays, defined collectively here as “dynamic patterns.” This study examines the nature, context, and potential functions of dynamic patterns across diverse cephalopod taxa. Examples are presented for 21 species, including 11 previously unreported in the scientific literature. These range from simple flashing or flickering patterns, to highly complex passing wave patterns involving multiple skin fields. PMID:28674500

  10. Microbial Extremophiles for Earth and Beyond: Pushing the Boundaries with Synthetic Biology

    NASA Technical Reports Server (NTRS)

    Rothschild, Lynn J.

    2017-01-01

    All organisms live in a multi-dimensional physical and chemical niche space. Discoveries in the 20th century enormously expanded the range of what was considered "habitable." However, the current diversity of life on Earth begs the question of what terrestrial life - or indeed, another life form - would be capable of. With the needs of both modern laboratory science and the burgeoning field of biotechnology, as well as our deeply held desire to answer the question "are we alone in the universe?, we are exploiting the tools of synthetic biology to probe the question of whether we can create "synthetic extremophiles" or, as our lab has dubbed them, "Hell Cells."

  11. Implementation for wideband applications using UWB fractal patch antenna

    NASA Astrophysics Data System (ADS)

    Kumar, D. Naresh

    2018-04-01

    This paper defines in detail about the diverse fractal patch antenna. Microstrip patch antennas has evolved in the field of research and development extending its impact across wide range of applications. A combination of patch antenna with fractal patterns has become a tryout to outspread it further. Because of its low profile nature patch antennas have added to a lot of prominence. Apart from have this property it can also be renovated further for wide bandwidth (2929 MHz) applications, as it exhibits self-analogous property. This antenna is premeditated on a patch using Sierpinski(4.040 GHz, 6.566 GHz) and Koch fractal geometries respectively. The antenna is designed using HFSS software.

  12. [Effects of rare earth elements on soil fauna community structure and their ecotoxicity to Holotrichia parallela].

    PubMed

    Li, Guiting; Jiang, Junqi; Chen, Jie; Zou, Yunding; Zhang, Xincai

    2006-01-01

    By the method of OECD filter paper contact, this paper studied the effects of applied rare earth elements on soil fauna community structure and their ecological toxicity to Holotrichia parallela in bean field. The results showed that there were no significant differences between the treatments and the control in soil fauna species, quantity of main species, and diversity index. Urgent and chronic toxic test showed that the differences between the treatments and the control were not significant. It was suggested that within the range of test dosages, rare earth elements had little ecological toxicity to Holotrichia parallela, and did not change the soil fauna community structure.

  13. KSC-08pd4126

    NASA Image and Video Library

    2008-12-23

    CAPE CANAVERAL, Fla. – A snowy egret stands in the shallow water of a pond in the Merritt island National Wildlife Refuge, which borders NASA's Kennedy Space Center in Florida. A type of heron, the snowy egret inhabits salt marshes, ponds, rice fields and shallow coastal bays ranging from Maine to southern South America on the east coast. It can also be found in California and Oklahoma to the Gulf of Mexico. The center shares a boundary with the refuge that includes salt-water estuaries, brackish marshes, hardwood hammocks and pine flatwoods. The diverse landscape provides habitat for more than 310 species of birds, 25 mammals, 117 fishes and 65 amphibians and reptiles. Photo credit: NASA/Jim Grossmann

  14. Protoplanetary disk observations in the ALMA era

    NASA Astrophysics Data System (ADS)

    Salyk, Colette

    2018-06-01

    In this talk, I’ll discuss how ALMA is advancing our understanding of protoplanetary disks with its unprecedented sensitivity and spatial resolution. In particular, I’ll focus on how ALMA is providing our first detailed view of gas-phase chemistry in giant planet forming regions, allowing us to test our ideas about how planets develop their diverse characteristics. Interpretation of these spectroscopic datasets requires sophisticated modeling tools and accurate laboratory data, as protoplanetary disks are ever-evolving environments that span a large range in density, temperature, and radiation field. I’ll discuss some recent results that highlight the important interplay between modeling and data analysis/interpretation, and suggest research directions that ALMA is likely to pursue going forward.

  15. Intuitive Physics: Current Research and Controversies.

    PubMed

    Kubricht, James R; Holyoak, Keith J; Lu, Hongjing

    2017-10-01

    Early research in the field of intuitive physics provided extensive evidence that humans succumb to common misconceptions and biases when predicting, judging, and explaining activity in the physical world. Recent work has demonstrated that, across a diverse range of situations, some biases can be explained by the application of normative physical principles to noisy perceptual inputs. However, it remains unclear how knowledge of physical principles is learned, represented, and applied to novel situations. In this review we discuss theoretical advances from heuristic models to knowledge-based, probabilistic simulation models, as well as recent deep-learning models. We also consider how recent work may be reconciled with earlier findings that favored heuristic models. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Diversity of soil fungi in North 24 Parganas and their antagonistic potential against Leucinodes orbonalis Guen. (Shoot and fruit borer of brinjal).

    PubMed

    Pal, Sujoy; Ghosh, Swapan Kumar

    2014-12-01

    Soil samples were collected from agricultural fields and gardens in North 24 Parganas, West Bengal, and fungi species were isolated from them. Thirty-one fungal species were isolated with 19 found in agricultural soil and 28 in garden soil. Twenty-eight out of 31 were identified using cultural and microscopic characters, and three were unidentified. The diversity of isolated fungi was calculated by Simpson's diversity index. The garden soil possessed more fungal colonies (750) than agricultural soil (477). In agricultural soil, the dominant fungi were Aspergillus niger, Rhizopus oryzae, and Penicillium expansum, and the dominant fungi of garden soil were A. niger and Fusarium moniliforme. Simpson's diversity index indicated that garden soil had more fungal diversity (0.939) than agricultural soil (0.896). The entomopathogenic capacity of the isolated fungi was tested against the brinjal shoot and fruit borer (Leucinodes orbonalis Guen) which is the major insect pest of brinjal. The isolated fungi were screened against larva of L. orbonalis for their entomopathogenic potential. Beauveria bassiana, A. niger, and P. expansum showed appreciable antagonism to L. orbonalis, and their lethal doses with 50 % mortality (LD50s) were 4.0 × 10(7), 9.06 × 10(7), and 1.50 × 10(8) spore/mL, respectively, and their times taken to reach 50 % mortality (LT50s) were 9.77, 10.56, and 10.60 days, respectively. This work suggests the restriction of chemical pesticide application in agricultural fields to increase fungal diversity. The entomopathogenic efficacy of B. bassiana could be used in agricultural fields to increase fugal diversity and protect the brinjal crop.

  17. DNA Polymorphism Among American Watermelon Cultivars Based on DNA Methylation

    USDA-ARS?s Scientific Manuscript database

    American watermelon heirlooms are diverse in their growth habits, fruit qualities and responses to biotic and abiotic stress. Wide ranging DNA marker tools resolved a narrow molecular diversity among these collections. The current research explored additional insights such as extent of diversity a...

  18. Field Validation of the Los Angeles Motor Scale as a Tool for Paramedic Assessment of Stroke Severity.

    PubMed

    Kim, Joon-Tae; Chung, Pil-Wook; Starkman, Sidney; Sanossian, Nerses; Stratton, Samuel J; Eckstein, Marc; Pratt, Frank D; Conwit, Robin; Liebeskind, David S; Sharma, Latisha; Restrepo, Lucas; Tenser, May-Kim; Valdes-Sueiras, Miguel; Gornbein, Jeffrey; Hamilton, Scott; Saver, Jeffrey L

    2017-02-01

    The Los Angeles Motor Scale (LAMS) is a 3-item, 0- to 10-point motor stroke-deficit scale developed for prehospital use. We assessed the convergent, divergent, and predictive validity of the LAMS when performed by paramedics in the field at multiple sites in a large and diverse geographic region. We analyzed early assessment and outcome data prospectively gathered in the FAST-MAG trial (Field Administration of Stroke Therapy-Magnesium phase 3) among patients with acute cerebrovascular disease (cerebral ischemia and intracranial hemorrhage) within 2 hours of onset, transported by 315 ambulances to 60 receiving hospitals. Among 1632 acute cerebrovascular disease patients (age 70±13 years, male 57.5%), time from onset to prehospital LAMS was median 30 minutes (interquartile range 20-50), onset to early postarrival (EPA) LAMS was 145 minutes (interquartile range 119-180), and onset to EPA National Institutes of Health Stroke Scale was 150 minutes (interquartile range 120-180). Between the prehospital and EPA assessments, LAMS scores were stable in 40.5%, improved in 37.6%, and worsened in 21.9%. In tests of convergent validity, against the EPA National Institutes of Health Stroke Scale, correlations were r=0.49 for the prehospital LAMS and r=0.89 for the EPA LAMS. Prehospital LAMS scores did diverge from the prehospital Glasgow Coma Scale, r=-0.22. Predictive accuracy (adjusted C statistics) for nondisabled 3-month outcome was as follows: prehospital LAMS, 0.76 (95% confidence interval 0.74-0.78); EPA LAMS, 0.85 (95% confidence interval 0.83-0.87); and EPA National Institutes of Health Stroke Scale, 0.87 (95% confidence interval 0.85-0.88). In this multicenter, prospective, prehospital study, the LAMS showed good to excellent convergent, divergent, and predictive validity, further establishing it as a validated instrument to characterize stroke severity in the field. © 2017 American Heart Association, Inc.

  19. Criterion 1: Conservation of biological diversity - Indicator 9: Population levels of representative species from diverse habitats monitored across their range

    Treesearch

    Carolyn Hull Sieg; Curtis H. Flather; Noah Barstatis

    2003-01-01

    This indicator estimates population trends of selected species as a surrogate measure of genetic diversity. Decreases in genetic diversity as populations decline, particularly if associated with small populations, contribute to increased risk of extinction. This indicator also provides an important measure of general biodiversity, as changes in species abundances are a...

  20. A novel complexity-to-diversity strategy for the diversity-oriented synthesis of structurally diverse and complex macrocycles from quinine.

    PubMed

    Ciardiello, J J; Stewart, H L; Sore, H F; Galloway, W R J D; Spring, D R

    2017-06-01

    Recent years have witnessed a global decline in the productivity and advancement of the pharmaceutical industry. A major contributing factor to this is the downturn in drug discovery successes. This can be attributed to the lack of structural (particularly scaffold) diversity and structural complexity exhibited by current small molecule screening collections. Macrocycles have been shown to exhibit a diverse range of biological properties, with over 100 natural product-derived examples currently marketed as FDA-approved drugs. Despite this, synthetic macrocycles are widely considered to be a poorly explored structural class within drug discovery, which can be attributed to their synthetic intractability. Herein we describe a novel complexity-to-diversity strategy for the diversity-oriented synthesis of novel, structurally complex and diverse macrocyclic scaffolds from natural product starting materials. This approach exploits the inherent structural (including functional) and stereochemical complexity of natural products in order to rapidly generate diversity and complexity. Readily-accessible natural product-derived intermediates serve as structural templates which can be divergently functionalized with different building blocks to generate a diverse range of acyclic precursors. Subsequent macrocyclisation then furnishes compounds that are each based around a distinct molecular scaffold. Thus, high levels of library scaffold diversity can be rapidly achieved. In this proof-of-concept study, the natural product quinine was used as the foundation for library synthesis, and six novel structurally diverse, highly complex and functionalized macrocycles were generated. Copyright © 2017 Elsevier Ltd. All rights reserved.

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