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Sample records for boris kruglikov valentin

  1. Valentine 2006

    NASA Technical Reports Server (NTRS)

    2006-01-01

    14 February 2006 Happy Valentine's Day from the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) team!

    This somewhat heart-shaped, eroded and partially-filled crater is located near the southeast wall of Columbus Crater in the Mare Sirenum region of Mars. North is toward the bottom/lower left.

    Location near: 29.9oS, 165.2oW Image width: 400 meter scale bar = 1,312 feet Illumination from: lower right Season: Southern Autumn

  2. Valentine's Day

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA02174 Valentine's Day

    This isolated mesa [lower left center of the image] has an almost heart-shaped margin. Happy Valentine's Day from Mars.

    Image information: VIS instrument. Latitude 29.4N, Longitude 79.1E. 18 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  3. Why is Boris Algorithm So Good?

    SciTech Connect

    et al, Hong Qin

    2013-03-03

    Due to its excellent long term accuracy, the Boris algorithm is the de facto standard for advancing a charged particle. Despite its popularity, up to now there has been no convincing explanation why the Boris algorithm has this advantageous feature. In this letter, we provide an answer to this question. We show that the Boris algorithm conserves phase space volume, even though it is not symplectic. The global bound on energy error typically associated with symplectic algorithms still holds for the Boris algorithm, making it an effective algorithm for the multi-scale dynamics of plasmas.

  4. Why is Boris algorithm so good?

    SciTech Connect

    Qin, Hong; Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 ; Zhang, Shuangxi; Xiao, Jianyuan; Liu, Jian; Sun, Yajuan; Tang, William M.

    2013-08-15

    Due to its excellent long term accuracy, the Boris algorithm is the de facto standard for advancing a charged particle. Despite its popularity, up to now there has been no convincing explanation why the Boris algorithm has this advantageous feature. In this paper, we provide an answer to this question. We show that the Boris algorithm conserves phase space volume, even though it is not symplectic. The global bound on energy error typically associated with symplectic algorithms still holds for the Boris algorithm, making it an effective algorithm for the multi-scale dynamics of plasmas.

  5. Valentine's Day: a Brief History and Game

    ERIC Educational Resources Information Center

    Maxwell, D. Jackson

    2009-01-01

    Valentine's Day presents an opportunity to show loved ones they are appreciated. Sweethearts, spouses, and families exchange gifts to express affection. Beyond traditional celebrations, new customs such as a romantic dinner, attending movies, and exchanging jewelry have been added. This article presents a brief history of Valentine's Day and a…

  6. CTCF and BORIS in genome regulation and cancer.

    PubMed

    Marshall, Amy D; Bailey, Charles G; Rasko, John E J

    2014-02-01

    CTCF plays a vital role in chromatin structure and function. CTCF is ubiquitously expressed and plays diverse roles in gene regulation, imprinting, insulation, intra/interchromosomal interactions, nuclear compartmentalisation, and alternative splicing. CTCF has a single paralogue, the testes-specific CTCF-like gene (CTCFL)/BORIS. CTCF and BORIS can be deregulated in cancer. The tumour suppressor gene CTCF can be mutated or deleted in cancer, or CTCF DNA binding can be altered by epigenetic changes. BORIS is aberrantly expressed frequently in cancer, leading some to propose a pro-tumourigenic role for BORIS. However, BORIS can inhibit cell proliferation, and is mutated in cancer similarly to CTCF suggesting BORIS activation in cancer may be due to global genetic or epigenetic changes typical of malignant transformation. PMID:24657531

  7. Streaming the Boris Pusher: a CUDA implementation

    SciTech Connect

    Abreu, Paulo; Fonseca, Ricardo; Silva, Luis O.

    2009-01-22

    We demonstrate an implementation of the Boris Particle Pusher Algorithm using CUDA-enabled processors. A simplified PIC code is used as a reference for the pusher and several tests are shown. The deployment time from a developer point of view is also evaluated. Results show that CUDA is a good tool for significant code acceleration with minimal code impact and minimal effort for the developer.

  8. 75 FR 15740 - Valentine Tool and Stamping, Inc.: Norton, MA; Notice of Termination of Investigation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Valentine Tool and Stamping, Inc.: Norton, MA; Notice of Termination... of Valentine Tool and Stamping, Inc., Norton, Massachusetts. The petitioner has requested that...

  9. Widespread expression of BORIS/CTCFL in normal and cancer cells.

    PubMed

    Jones, Tania A; Ogunkolade, Babatunji W; Szary, Jaroslaw; Aarum, Johan; Mumin, Muhammad A; Patel, Shyam; Pieri, Christopher A; Sheer, Denise

    2011-01-01

    BORIS (CTCFL) is the paralog of CTCF (CCCTC-binding factor; NM_006565), a ubiquitously expressed DNA-binding protein with diverse roles in gene expression and chromatin organisation. BORIS and CTCF have virtually identical zinc finger domains, yet display major differences in their respective C- and N-terminal regions. Unlike CTCF, BORIS expression has been reported only in the testis and certain malignancies, leading to its classification as a "cancer-testis" antigen. However, the expression pattern of BORIS is both a significant and unresolved question in the field of DNA binding proteins. Here, we identify BORIS in the cytoplasm and nucleus of a wide range of normal and cancer cells. We compare the localization of CTCF and BORIS in the nucleus and demonstrate enrichment of BORIS within the nucleolus, inside the nucleolin core structure and adjacent to fibrillarin in the dense fibrillar component. In contrast, CTCF is not enriched in the nucleolus. Live imaging of cells transiently transfected with GFP tagged BORIS confirmed the nucleolar accumulation of BORIS. While BORIS transcript levels are low compared to CTCF, its protein levels are readily detectable. These findings show that BORIS expression is more widespread than previously believed, and suggest a role for BORIS in nucleolar function. PMID:21811597

  10. High Expression of hTERT and Stemness Genes in BORIS/CTCFL Positive Cells Isolated from Embryonic Cancer Cells

    PubMed Central

    Alberti, Loredana; Renaud, Stéphanie; Losi, Lorena; Leyvraz, Serge; Benhattar, Jean

    2014-01-01

    BORIS/CTCFL is a member of cancer testis antigen family normally expressed in germ cells. In tumors, it is aberrantly expressed although its functions are not completely well-defined. To better understand the functions of BORIS in cancer, we selected the embryonic cancer cells as a model. Using a molecular beacon, which specifically targets BORIS mRNA, we demonstrated that BORIS positive cells are a small subpopulation of tumor cells (3–5% of total). The BORIS-positive cells isolated using BORIS-molecular beacon, expressed higher telomerase hTERT, stem cell (NANOG, OCT4, SOX2) and cancer stem cell marker genes (CD44 and ALDH1) compared to the BORIS-negative tumor cells. In order to define the functional role of BORIS, stable BORIS-depleted embryonic cancer cells were generated. BORIS silencing strongly down-regulated the expression of hTERT, stem cell and cancer stem cell marker genes. Moreover, the BORIS knockdown increased cellular senescence in embryonic cancer cells, revealing a putative role of BORIS in the senescence biological program. Our data indicate an association of BORIS expressing cells subpopulation with the expression of stemness genes, highlighting the critical role played by BORIS in embryonic neoplastic disease. PMID:25279549

  11. The evolution of epigenetic regulators CTCF and BORIS/CTCFL in amniotes.

    PubMed

    Hore, Timothy A; Deakin, Janine E; Marshall Graves, Jennifer A

    2008-08-01

    CTCF is an essential, ubiquitously expressed DNA-binding protein responsible for insulator function, nuclear architecture, and transcriptional control within vertebrates. The gene CTCF was proposed to have duplicated in early mammals, giving rise to a paralogue called "brother of regulator of imprinted sites" (BORIS or CTCFL) with DNA binding capabilities similar to CTCF, but testis-specific expression in humans and mice. CTCF and BORIS have opposite regulatory effects on human cancer-testis genes, the anti-apoptotic BAG1 gene, the insulin-like growth factor 2/H19 imprint control region (IGF2/H19 ICR), and show mutually exclusive expression in humans and mice, suggesting that they are antagonistic epigenetic regulators. We discovered orthologues of BORIS in at least two reptilian species and found traces of its sequence in the chicken genome, implying that the duplication giving rise to BORIS occurred much earlier than previously thought. We analysed the expression of CTCF and BORIS in a range of amniotes by conventional and quantitative PCR. BORIS, as well as CTCF, was found widely expressed in monotremes (platypus) and reptiles (bearded dragon), suggesting redundancy or cooperation between these genes in a common amniote ancestor. However, we discovered that BORIS expression was gonad-specific in marsupials (tammar wallaby) and eutherians (cattle), implying that a functional change occurred in BORIS during the early evolution of therian mammals. Since therians show imprinting of IGF2 but other vertebrate taxa do not, we speculate that CTCF and BORIS evolved specialised functions along with the evolution of imprinting at this and other loci, coinciding with the restriction of BORIS expression to the germline and potential antagonism with CTCF. PMID:18769711

  12. The Evolution of Epigenetic Regulators CTCF and BORIS/CTCFL in Amniotes

    PubMed Central

    Hore, Timothy A.; Deakin, Janine E.; Marshall Graves, Jennifer A.

    2008-01-01

    CTCF is an essential, ubiquitously expressed DNA-binding protein responsible for insulator function, nuclear architecture, and transcriptional control within vertebrates. The gene CTCF was proposed to have duplicated in early mammals, giving rise to a paralogue called “brother of regulator of imprinted sites” (BORIS or CTCFL) with DNA binding capabilities similar to CTCF, but testis-specific expression in humans and mice. CTCF and BORIS have opposite regulatory effects on human cancer-testis genes, the anti-apoptotic BAG1 gene, the insulin-like growth factor 2/H19 imprint control region (IGF2/H19 ICR), and show mutually exclusive expression in humans and mice, suggesting that they are antagonistic epigenetic regulators. We discovered orthologues of BORIS in at least two reptilian species and found traces of its sequence in the chicken genome, implying that the duplication giving rise to BORIS occurred much earlier than previously thought. We analysed the expression of CTCF and BORIS in a range of amniotes by conventional and quantitative PCR. BORIS, as well as CTCF, was found widely expressed in monotremes (platypus) and reptiles (bearded dragon), suggesting redundancy or cooperation between these genes in a common amniote ancestor. However, we discovered that BORIS expression was gonad-specific in marsupials (tammar wallaby) and eutherians (cattle), implying that a functional change occurred in BORIS during the early evolution of therian mammals. Since therians show imprinting of IGF2 but other vertebrate taxa do not, we speculate that CTCF and BORIS evolved specialised functions along with the evolution of imprinting at this and other loci, coinciding with the restriction of BORIS expression to the germline and potential antagonism with CTCF. PMID:18769711

  13. CTCFL (BORIS) mRNA Expression in a Peripheral Giant Cell Granuloma of the Oral Cavity

    PubMed Central

    Zambrano-Galván, Graciela; Reyes-Romero, Miguel; Bologna-Molina, Ronell; Almeda-Ojeda, Oscar Eduardo; Lemus-Rojero, Obed

    2014-01-01

    Peripheral giant cell granuloma (PGCG) is a relatively common benign reactive lesion of the oral cavity which can occur at any age. CTCFL/BORIS (CTCF like/Brother of the Regulator of Imprinted Sites) and CTCF (CCCTC-binding factor) are paralogous genes with an important role in the regulation of gene expression, genomic imprinting, and nuclear chromatin insulators regulation. BORIS expression promotes cell immortalization and growth while CTCF has tumor suppressor activity; the expression pattern may reflect the reverse transcription silencing of BORIS. The aim of this work was to describe a histopathological and molecular approach of an 8-year-old pediatric male patient with PGCG diagnosis. It was observed that the PGCG under study expressed CTCF as well as BORIS mRNAs alongside with the housekeeping gene GAPDH, which may be related to possible genetic and epigenetic changes in normal cells of oral cavity. PMID:25114808

  14. NASA's TRMM Satellite Sees Mexico Soaked from Boris, System 90L

    NASA Video Gallery

    TRMM satellite data showed that some areas in southwestern Mexico received over 12 inches of rainfall (red) from Boris, while System 90L on the eastern side of Mexico brought similar totals to part...

  15. Brother of the regulator of the imprinted site (BORIS) variant subfamily 6 is involved in cervical cancer stemness and can be a target of immunotherapy

    PubMed Central

    Asano, Takuya; Hirohashi, Yoshihiko; Torigoe, Toshihiko; Mariya, Tasuku; Horibe, Ryota; Kuroda, Takafumi; Tabuchi, Yuta; Saijo, Hiroshi; Yasuda, Kazuyo; Mizuuchi, Masahito; Takahashi, Akari; Asanuma, Hiroko; Hasegawa, Tadashi; Saito, Tsuyoshi; Sato, Noriyuki

    2016-01-01

    Cervical cancer is a major cause of cancer death in females worldwide. Cervical cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) are resistant to conventional radiotherapy and chemotherapy, and CSCs/CICs are thought to be responsible for recurrence. Eradication of CSCs/CICs is thus essential to cure cervical cancer. In this study, we isolated cervical CSCs/CICs by sphere culture, and we identified a cancer testis (CT) antigen, CTCFL/BORIS, that is expressed in cervical CSCs/CICs. BORIS has 23 mRNA isoform variants classified by 6 subfamilies (sfs), and they encode 17 different BORIS peptides. BORIS sf1 and sf4 are expressed in both CSCs/CICs and non-CSCs/CICs, whereas BORIS sf6 is expressed only in CSCs/CICs. Overexpression of BORIS sf6 in cervical cancer cells increased sphere formation and tumor-initiating ability compared with those in control cells, whereas overexpression of BORIS sf1 and BORIS sf4 resulted in only slight increases. Thus, BORIS sf6 is a cervical CSC/CIC-specific subfamily and has a role in the maintenance of cervical CSCs/CICs. BORIS sf6 contains a specific c-terminal domain (C34), and we identified a human leukocyte antigen (HLA)-A2-restricted antigenic peptide, BORIS C34_24(9) encoded by BORIS sf6. A BORIS C34_24(9)-specific cytotoxic T cell (CTL) clone showed cytotoxicity for BORIS sf6-overexpressing cervical cancer cells. Furthermore, the CTL clone significantly suppressed sphere formation of CaSki cells. Taken together, the results indicate that the CT antigen BORIS sf6 is specifically expressed in cervical CSCs/CICs, that BORIS sf6 has a role in the maintenance of CSCs/CICs, and that BORIS C34_24(9) peptide is a promising candidate for cervical CSC/CIC-targeting immunotherapy. PMID:26849232

  16. Brother of the regulator of the imprinted site (BORIS) variant subfamily 6 is involved in cervical cancer stemness and can be a target of immunotherapy.

    PubMed

    Asano, Takuya; Hirohashi, Yoshihiko; Torigoe, Toshihiko; Mariya, Tasuku; Horibe, Ryota; Kuroda, Takafumi; Tabuchi, Yuta; Saijo, Hiroshi; Yasuda, Kazuyo; Mizuuchi, Masahito; Takahashi, Akari; Asanuma, Hiroko; Hasegawa, Tadashi; Saito, Tsuyoshi; Sato, Noriyuki

    2016-03-01

    Cervical cancer is a major cause of cancer death in females worldwide. Cervical cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) are resistant to conventional radiotherapy and chemotherapy, and CSCs/CICs are thought to be responsible for recurrence. Eradication of CSCs/CICs is thus essential to cure cervical cancer. In this study, we isolated cervical CSCs/CICs by sphere culture, and we identified a cancer testis (CT) antigen, CTCFL/BORIS, that is expressed in cervical CSCs/CICs. BORIS has 23 mRNA isoform variants classified by 6 subfamilies (sfs), and they encode 17 different BORIS peptides. BORIS sf1 and sf4 are expressed in both CSCs/CICs and non-CSCs/CICs, whereas BORIS sf6 is expressed only in CSCs/CICs. Overexpression of BORIS sf6 in cervical cancer cells increased sphere formation and tumor-initiating ability compared with those in control cells, whereas overexpression of BORIS sf1 and BORIS sf4 resulted in only slight increases. Thus, BORIS sf6 is a cervical CSC/CIC-specific subfamily and has a role in the maintenance of cervical CSCs/CICs. BORIS sf6 contains a specific c-terminal domain (C34), and we identified a human leukocyte antigen (HLA)-A2-restricted antigenic peptide, BORIS C34_24(9) encoded by BORIS sf6. A BORIS C34_24(9)-specific cytotoxic T cell (CTL) clone showed cytotoxicity for BORIS sf6-overexpressing cervical cancer cells. Furthermore, the CTL clone significantly suppressed sphere formation of CaSki cells. Taken together, the results indicate that the CT antigen BORIS sf6 is specifically expressed in cervical CSCs/CICs, that BORIS sf6 has a role in the maintenance of CSCs/CICs, and that BORIS C34_24(9) peptide is a promising candidate for cervical CSC/CIC-targeting immunotherapy. PMID:26849232

  17. Review on Panton Valentine leukocidin toxin carriage among Staphylococcus aureus.

    PubMed

    Shrestha, B

    2013-09-01

    Panton Valentine leukocidin is a toxin making pores in the polymorphonuclear cells which is a virulence factor of some strains of Staphylococcus aureus. Initially it was produced by methicillin susceptible Staphylococcus aureus only. Later with the acquisition of mecA gene has lead it to be PVL positive methicillin resistant Staphylococcus aureus. Since MRSA are resistant to many antibiotics and further they produce a toxin the infections by PVL positive MRSA has become a challenge. PVL positive MRSA a virulent strain of drug resistant superbug MRSA that has spread around the world, has claimed many lives in UK, Europe, USA and Australia. Some strains of superbug attack the healthy young people and kill within 24 hrs. PVL positive Staphylococcus aureus has been reported to be associated with skin and soft tissue infections however they also cause invasive infections and necrotizing pneumonia. These microorganisms known to be community associated have spread to hospitals. Hospital acquired infection by such microorganisms lead to an increase in mortality hence should be controlled before they become prevalent in hospitals. PMID:24908537

  18. A polymorphic minisatellite region of BORIS regulates gene expression and its rare variants correlate with lung cancer susceptibility

    PubMed Central

    Yoon, Se-Lyun; Roh, Yun-Gil; Chu, In-Sun; Heo, Jeonghoon; Kim, Seung Il; Chang, Heekyung; Kang, Tae-Hong; Chung, Jin Woong; Koh, Sang Seok; Larionov, Vladimir; Leem, Sun-Hee

    2016-01-01

    Aberrant expression of BORIS/CTCFL (Brother of the Regulator of Imprinted Sites/CTCF-like protein) is reported in different malignancies. In this study, we characterized the entire promoter region of BORIS/CTCFL, including the CpG islands, to assess the relationship between BORIS expression and lung cancer. To simplify the construction of luciferase reporter cassettes with various-sized portions of the upstream region, genomic copies of BORIS were isolated using TAR cloning technology. We analyzed three promoter blocks: the GATA/CCAAT box, the CpG islands and the minisatellite region BORIS-MS2. Polymorphic minisatellite sequences were isolated from genomic DNA prepared from the blood of controls and cases. Of the three promoter blocks, the GATA/CCAAT box was determined to be a critical element of the core promoter, while the CpG islands and the BORIS-MS2 minisatellite region were found to act as regulators. Interestingly, the polymorphic minisatellite region BORIS-MS2 was identified as a negative regulator that repressed the expression levels of luciferase reporter cassettes less effectively in cancer cells compared with normal cells. We also examined the association between the size of BORIS-MS2 and lung cancer in a case–control study with 590 controls and 206 lung cancer cases. Rare alleles of BORIS-MS2 were associated with a statistically significantly increased risk of lung cancer (odds ratio, 2.04; 95% confidence interval, 1.02–4.08; and P=0.039). To conclude, our data provide information on the organization of the BORIS promoter region and gene regulation in normal and cancer cells. In addition, we propose that specific alleles of the BORIS-MS2 region could be used to identify the risk for lung cancer. PMID:27416782

  19. A polymorphic minisatellite region of BORIS regulates gene expression and its rare variants correlate with lung cancer susceptibility.

    PubMed

    Yoon, Se-Lyun; Roh, Yun-Gil; Chu, In-Sun; Heo, Jeonghoon; Kim, Seung Il; Chang, Heekyung; Kang, Tae-Hong; Chung, Jin Woong; Koh, Sang Seok; Larionov, Vladimir; Leem, Sun-Hee

    2016-01-01

    Aberrant expression of BORIS/CTCFL (Brother of the Regulator of Imprinted Sites/CTCF-like protein) is reported in different malignancies. In this study, we characterized the entire promoter region of BORIS/CTCFL, including the CpG islands, to assess the relationship between BORIS expression and lung cancer. To simplify the construction of luciferase reporter cassettes with various-sized portions of the upstream region, genomic copies of BORIS were isolated using TAR cloning technology. We analyzed three promoter blocks: the GATA/CCAAT box, the CpG islands and the minisatellite region BORIS-MS2. Polymorphic minisatellite sequences were isolated from genomic DNA prepared from the blood of controls and cases. Of the three promoter blocks, the GATA/CCAAT box was determined to be a critical element of the core promoter, while the CpG islands and the BORIS-MS2 minisatellite region were found to act as regulators. Interestingly, the polymorphic minisatellite region BORIS-MS2 was identified as a negative regulator that repressed the expression levels of luciferase reporter cassettes less effectively in cancer cells compared with normal cells. We also examined the association between the size of BORIS-MS2 and lung cancer in a case-control study with 590 controls and 206 lung cancer cases. Rare alleles of BORIS-MS2 were associated with a statistically significantly increased risk of lung cancer (odds ratio, 2.04; 95% confidence interval, 1.02-4.08; and P=0.039). To conclude, our data provide information on the organization of the BORIS promoter region and gene regulation in normal and cancer cells. In addition, we propose that specific alleles of the BORIS-MS2 region could be used to identify the risk for lung cancer. PMID:27416782

  20. Mainstream legitimization of homosexual men through Valentine's Day gift-giving and consumption rituals.

    PubMed

    Newman, P J; Nelson, M R

    1996-01-01

    Recently, the gay community has received increased attention from marketers through specially-made television commercials, direct mail pieces, and other media messages. However, little research in consumer behavior has examined the potential attitudinal and behavioral differences and similarities between heterosexuals and homosexuals. Specifically, this paper provides an exploratory look at the meaning and practices surrounding the consumer ritual of Valentine's Day from the perspective of homosexual men. Using depth interviews within an interpretative framework, our research suggests similarities exist for the celebration of Valentine's Day between homosexual and heterosexual singles, while differences may exist for the functions of Valentine's Day gift-giving between these groups. Some homosexual couples feel they cannot "legitimately participate" in the dominant rituals associated with the holiday due to oppression by a "heterosexual society". Marketing implications are discussed. PMID:8827492

  1. The novel BORIS + CTCF gene family is uniquely involved in the epigenetics of normal biology and cancer.

    PubMed

    Klenova, Elena M; Morse, Herbert C; Ohlsson, Rolf; Lobanenkov, Victor V

    2002-10-01

    CTCF is a ubiquitous 11 zinc finger (ZF) protein with highly versatile functions: in addition to transcriptional silencing or activating in a context-dependent fashion, it organizes epigenetically controlled chromatin insulators that regulate imprinted genes in soma. Recently, we have identified a CTCF paralogue, termed BORIS for Brother of the Regulator of Imprinted Sites, that is expressed only in the testis. BORIS has the same exons encoding the 11 ZF domain as mammalian CTCF genes, and hence interacts with similar cis elements, but encodes amino and carboxy termini distinct from those in CTCF. Normally, CTCF and BORIS are expressed in a mutually exclusive pattern that correlates with re-setting of methylation marks during male germ cell differentiation. The antagonistic features of these two gene siblings are underscored by showing that while CTCF overexpression blocks cell proliferation, expression of BORIS in normally BORIS-negative cells promotes cell growth which can lead to transformation. The suggestion that BORIS directs epigenetic reprogramming at CTCF target sites impinges on the observations that human BORIS is not only abnormally activated in a wide range of human cancers, but also maps to the cancer-associated amplification region at 20q13. The sibling rivalry occasioned by aberrant expression of BORIS in cancer may interfere with normal functions of CTCF including growth suppression, and contribute to epigenetic dysregulation which is a common feature in human cancer. PMID:12191639

  2. [Severe infection by methicillin sensitive Staphylococcus aureus producing Panton-Valentine leukocidin: reports of two cases].

    PubMed

    Brizuela, Martín; Pérez, Guadalupe; Ruvinsky, Silvina; Sarkis, Claudia; Romero, Romina; Mastroianni, Alejandra; Casimir, Lidia; Venuta, María E; Gómez Bonduele, Verónica; Bologna, Rosa

    2016-08-01

    Staphylococcus aureus is a major etiologic agent of infections in children from the community and the hospital setting. The severity of these conditions is associated with virulence factors, including the Panton-Valentine leukocidin. Both methicillin resistant and sensitive Staphylococcus aureus produce this leukocidin although with varying frequency. We present two children with severe infection by sensitive Staphylococcus aureus producer of Panton-Valentine leukocidin with musculoskeletal and endovascular complications. It is essential the suspected diagnosis, appropriate antibiotic treatment and early surgical management to improve the approach of these infections. Epidemiological surveillance should be mantained to detect the frequency of infections caused by these bacteria. PMID:27399020

  3. [Valentine's Day Activities Compiled from Eleven Years of February Issues of Instructor Magazine, 1973-1983.

    ERIC Educational Resources Information Center

    Instructor, 1983

    1983-01-01

    Valentine's Day activities which include a play, music, poetry, and numerous art and craft projects are presented in this compilation from February issues of "Instructor" magazine. The short and easy projects, suitable for primary and elementary students, use inexpensive and easily found materials such as paper, cloth, yarn, magazine pictures,…

  4. 76 FR 18291 - Culturally Significant Objects Imported for Exhibition Determinations: “Boris Mikhailov: Case...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-01

    ... Culturally Significant Objects Imported for Exhibition Determinations: ``Boris Mikhailov: Case History... Mikhailov: Case History,'' imported from abroad for temporary exhibition within the United States, are of... Art, New York, New York, from on or about May 26, 2011, until on or about September 5, 2011, and...

  5. Seismo-acoustic effects of sonic booms on archeological sites, Valentine Military Operations Area

    NASA Astrophysics Data System (ADS)

    Battis, J. C.

    1983-11-01

    Seismo-acoustic recordings of sonic booms were made at two sites in the Valentine Military Operations Areas (MOA). Each location was selected as representative of a class of significant archeological sites found within the MOA. These studies indicate that sonic booms are unlikely to cause damage to the archeological finds. The expected motions are, at worst, 8 percent of the limits set by strict blasting codes and comparable to velocities that could be produced by local earthquakes which have occurred in the Valentine area. At these levels of motion, competent rock will be unaffected by the transmission of seismic waves. The predicted velocity levels are unlikely to initiate either fracture or spalling in rocks. However, it is possible that in rocks where natural meteorological action has initiated these erosive mechanisms the sonic boom induced motion accelerate the processes to some small, and probably insignificant, degree.

  6. Outbreak of Panton-Valentine Leukocidin-Associated Methicillin-Susceptible Staphylococcus aureus Infection in a Rugby Team, France, 2010-2011.

    PubMed

    Couvé-Deacon, Elodie; Tristan, Anne; Pestourie, Nathalie; Faure, Christian; Doffoel-Hantz, Valérie; Garnier, Fabien; Laurent, Frédéric; Lina, Gerard; Ploy, Marie-Cecile

    2016-01-01

    Staphylococcus aureus strains that produce Panton-Valentine leukocidin are known to cause community infections. We describe an outbreak of skin abscesses caused by Panton-Valentine leukocidin-producing methicillin-susceptible S. aureus (clonal complex 121) in a professional rugby team in France during July 2010-February 2011. Eight team members were carriers; 7 had skin abscesses. PMID:26690308

  7. Outbreak of Panton-Valentine Leukocidin–Associated Methicillin-Susceptible Staphylococcus aureus Infection in a Rugby Team, France, 2010–2011

    PubMed Central

    Couvé-Deacon, Elodie; Tristan, Anne; Pestourie, Nathalie; Faure, Christian; Doffoel-Hantz, Valérie; Garnier, Fabien; Laurent, Frédéric; Lina, Gerard

    2016-01-01

    Staphylococcus aureus strains that produce Panton-Valentine leukocidin are known to cause community infections. We describe an outbreak of skin abscesses caused by Panton-Valentine leukocidin–producing methicillin-susceptible S. aureus (clonal complex 121) in a professional rugby team in France during July 2010–February 2011. Eight team members were carriers; 7 had skin abscesses. PMID:26690308

  8. A Valentine's Day bouquet for Temperature readers: pleasing with prizes, searching for the right words, and keeping things mysterious.

    PubMed

    Romanovsky, Andrej A

    2015-01-01

    This editorial tells its readers that the journal Temperature awards its first prizes for best papers to Boris Kingma and Assaf Yacobi. It also discusses the use of several thermoregulation-related terms and expressions, including "cold temperature," "thermoneutral temperature," and "warm-sensitive" and offers, arguably, better alternatives. The editorial also contains a new puzzle: how can color affect temperature perception? PMID:27226997

  9. [Valentin Sergeevich Kirpichnikov: on the 100th anniversary of his birth (1908-1991)].

    PubMed

    Golubovsiĭ, M D

    2008-07-01

    Valentin Sergeevich Kirpichnikov is an outstanding Russian biologist, geneticist, and evolutionist. In his work, the true interest to the theory of evolution was harmoniously combined with long-term successful research into fish genetics and breeding. In 1987, Kirpichnikov published a fundamental treatise entitled "Fish Genetics and Breeding," which was immediately translated into English, German, and Japanese and still remains the most comprehensive handbook in this field. The authority of Kirpichnikov was confirmed by his election to the International Association of Aquaculture and an expert of the leading international organization on food and agriculture, FAO, with the United Nations. During the hard years in the history of Soviet biology, the courage and fidelity to the principles in defending the scientific biology and opposing Lysenko's obscurantism won Valentin Sergeevich the deserved name of a "knight of science". His mode of speech at the seminars and in discussions was unhurried, calm, and fitting. Yet especially important moments supplemented his baritone with hard metal modulations, which revealed the concealed passion and conviction in the defended truth. PMID:18767534

  10. Integration of Full Particle Orbit in Toroidal Plasmas Using Boris Scheme

    NASA Astrophysics Data System (ADS)

    Wei, Xishuo; Xiao, Yong

    2014-10-01

    When studying particle dynamics in high frequency electromagnetic waves, such as low hybrid wave heating, it is important to integrate full particle orbit accurately to very long time in tokamaks. Here we derived a formulation under magnetic coordinate based on the Boris Scheme, which can be used effectively to push particles in long time scale. After several hundred gyro-periods, the banana orbit can be observed and the toroidal precession frequency can be measured. The toroidal precession frequency is found to match that from the guiding center simulation. This new method shows superior numeric properties than the traditional Runge-Kutta method in terms of conserving particle energy and magnetic moment.

  11. A Valentine's Day bouquet for Temperature readers: pleasing with prizes, searching for the right words, and keeping things mysterious

    PubMed Central

    Romanovsky, Andrej A

    2015-01-01

    This editorial tells its readers that the journal Temperature awards its first prizes for best papers to Boris Kingma and Assaf Yacobi. It also discusses the use of several thermoregulation-related terms and expressions, including “cold temperature,” “thermoneutral temperature,” and “warm-sensitive” and offers, arguably, better alternatives. The editorial also contains a new puzzle: how can color affect temperature perception? PMID:27226997

  12. [On a contribution of Boris Balinsky to the comparative and ecological embryology of amphibians].

    PubMed

    Desnitskiĭ, A G

    2014-01-01

    The outstanding embryologist Boris Ivanovich Balinsky (1905-1997) worked in the Soviet Union up to 1941 and in South Africa since 1949. His experimental studies fulfilled during the Soviet period of his scientific career mainly on the embryos of the caudate amphibians are widely known. After moving to Africa (Johannesburg), he continued the research of amphibian development, with using those possibilities, which were offered by the diverse fauna of local Anura. Other embryologists started complex studies of tropical frog ontogenies (mainly from South and Central America) 30-40 years later than Balinsky. Unfortunately, his pioneering works on numerous African species are poorly known (with the exceptions of the description of the development of endodermal derivatives in Xenopus laevis and the analysis of limb induction in the toad genus Amietophrynus). In this paper, the works of Balinsky are analyzed (with the emphasis on comparative and ecological aspects) and his priority in using of "nonmodel" tropical and subtropical anurans in embryological studies has been shown. PMID:25720271

  13. Growth rate of Usnea aurantiacoatra (Jacq.) Bory on Fildes Peninsula, Antarctica and its climatic background.

    PubMed

    Li, Ying; Kromer, Bernd; Schukraft, Gerd; Bubenzer, Olaf; Huang, Man-Rong; Wang, Ze-Min; Bian, Lin-Gen; Li, Cheng-Sen

    2014-01-01

    The ages of a fruticose lichen of Usnea aurantiacoatra (Jacq.) Bory, from Fildes Peninsula, King George Island, Southwest Antarctic, were determined by radiocarbon (14C), and it is 1993-1996 at bottom and 2006-2007 at top of the lichen branch. The growth rates of U. aurantiacoatra calculated are 4.3 to 5.5 mm year(-1) based on its length and ages. The comparisons show that the growth rates of U. aurantiacoatra are higher than those of U. antarctica (0.4 to 1.1 mm year(-1)). The growth rates of fruticose lichens are always higher, usually >2 mm year(-1), than those of crustose ones, usually <1 mm year(-1), in polar areas. A warming trend on Fildes Peninsula is recorded in the period from 1969 to 2010 obviously: the mean annual temperature rose from -2.75 to -1.9°C and the average temperature of summer months from 0.95 to 1.4°C, as well as the average temperature of winter months from -6.75 to -5.5°C. The alteration of lichen growth rates in polar areas may respond to the climatic and environmental changes, and the lichens may act as bio-monitor of natural condition. PMID:24968131

  14. Growth Rate of Usnea aurantiacoatra (Jacq.) Bory on Fildes Peninsula, Antarctica and Its Climatic Background

    PubMed Central

    Li, Ying; Kromer, Bernd; Schukraft, Gerd; Bubenzer, Olaf; Huang, Man-Rong; Wang, Ze-Min; Bian, Lin-Gen; Li, Cheng-Sen

    2014-01-01

    The ages of a fruticose lichen of Usnea aurantiacoatra (Jacq.) Bory, from Fildes Peninsula, King George Island, Southwest Antarctic, were determined by radiocarbon (14C), and it is 1993–1996 at bottom and 2006–2007 at top of the lichen branch. The growth rates of U. aurantiacoatra calculated are 4.3 to 5.5 mm year−1 based on its length and ages. The comparisons show that the growth rates of U. aurantiacoatra are higher than those of U. antarctica (0.4 to 1.1 mm year−1). The growth rates of fruticose lichens are always higher, usually >2 mm year−1, than those of crustose ones, usually <1 mm year−1, in polar areas. A warming trend on Fildes Peninsula is recorded in the period from 1969 to 2010 obviously: the mean annual temperature rose from −2.75 to −1.9°C and the average temperature of summer months from 0.95 to 1.4°C, as well as the average temperature of winter months from −6.75 to −5.5°C. The alteration of lichen growth rates in polar areas may respond to the climatic and environmental changes, and the lichens may act as bio-monitor of natural condition. PMID:24968131

  15. Investigations on modern carbon materials in the Boris Kidrič Institute, Vinča

    NASA Astrophysics Data System (ADS)

    Marinković, Slobodan

    1980-03-01

    Modern carbon materials which have been objects of research at the Boris Kidrič Institute, Vinča involve high-performance carbon fibres from PAN precursor, carbon-fibre-reinforced phenolic and epoxy resins, carbon-carbon composites, pyrolytic carbons deposited at 1500-2450 K both pure and containing small amounts of B, Si, P or U, and carbon felt from viscose rayon precursor. Investigations relevant to carbon fibres comprise a study of processes during air oxidation of PAN fibres and an extensive research of low-temperature SO 2-treatment of PAN fibres, which has resulted in a model of the structure stabilization and shows that this stabilization can be successfully applied for the preparation of high-performance carbon fibres. Extensive investigations of codeposition of carbon and small amounts of B, Si, P and U suggest that B, Si and P enter the pyrocarbon lattice substitutionally and produce important changes in properties of the product. B, Si and U act as graphitizing catalysts, the effect being most pronounced for Si. The fabrication technology of the carbon fibres, carbon-fibre-reinforced-plastics and of pyrolytic carbon has been developed on a laboratory scale.

  16. Development and usage of protein microarrays for the quantitative measurement of Panton-Valentine leukocidin.

    PubMed

    Stieber, Bettina; Monecke, Stefan; Müller, Elke; Baier, Vico; Coombs, Geoffrey W; Ehricht, Ralf

    2014-08-01

    Staphylococcus aureus is a human pathogen that can harbour several genes encoding exotoxins including leukocidins. A clinically most relevant factor is Panton-Valentine leukocidin (PVL) because of its association with chronic, recurrent or severe skin and soft tissue infections. In this study an antibody array was designed and used to obtain an overview about the in vitro PVL expression levels of 266 clinical isolates of MRSA as well as of MSSA belonging to a wide variety of clonal complexes. For that purpose, a novel precipitation based method was used. Unknown PVL concentrations were determined by mapping the signal intensities for spotted monoclonal antibodies to calibration curves that resulted from experiments with known concentrations of recombinant LukF-PV. In most cases, isolates belonging to one clonal complex (CC) showed similar PVL expressions. However, there were also CCs with widely varying PVL concentrations. First analyses, based on in vitro PVL measurements, showed low PVL concentrations in isolates from severe and fatal conditions that are not associated with PVL, such as sepsis, while isolates from skin and soft tissue infections yielded higher concentrations. Agr-group I and IV isolates generally produced more PVL than isolates from agr-groups II and III. The few isolates harbouring the gene encoding toxic shock syndrome toxin (tst1) were particularly low level PVL producers. However, these issues warrant further studies. The method described herein allows rapid quantification of expressed proteins such as PVL in collections of clinical isolates in order to correlate with clinical or genotypic data with a potential for further parallelisation. PMID:24308917

  17. Staphylococcus aureus Panton-Valentine Leukocidin Is a Very Potent Cytotoxic Factor for Human Neutrophils

    PubMed Central

    Löffler, Bettina; Hussain, Muzaffar; Grundmeier, Matthias; Brück, Michaela; Holzinger, Dirk; Varga, Georg; Roth, Johannes; Kahl, Barbara C.; Proctor, Richard A.; Peters, Georg

    2010-01-01

    The role of the pore-forming Staphylococcus aureus toxin Panton-Valentine leukocidin (PVL) in severe necrotizing diseases is debated due to conflicting data from epidemiological studies of community-associated methicillin-resistant S. aureus (CA-MRSA) infections and various murine disease-models. In this study, we used neutrophils isolated from different species to evaluate the cytotoxic effect of PVL in comparison to other staphylococcal cytolytic components. Furthermore, to study the impact of PVL we expressed it heterologously in a non-virulent staphylococcal species and examined pvl-positive and pvl-negative clinical isolates as well as the strain USA300 and its pvl-negative mutant. We demonstrate that PVL induces rapid activation and cell death in human and rabbit neutrophils, but not in murine or simian cells. By contrast, the phenol-soluble modulins (PSMs), a newly identified group of cytolytic staphylococcal components, lack species-specificity. In general, after phagocytosis of bacteria different pvl-positive and pvl-negative staphylococcal strains, expressing a variety of other virulence factors (such as surface proteins), induced cell death in neutrophils, which is most likely associated with the physiological clearing function of these cells. However, the release of PVL by staphylococcal strains caused rapid and premature cell death, which is different from the physiological (and programmed) cell death of neutrophils following phagocytosis and degradation of virulent bacteria. Taken together, our results question the value of infection-models in mice and non-human primates to elucidate the impact of PVL. Our data clearly demonstrate that PVL acts differentially on neutrophils of various species and suggests that PVL has an important cytotoxic role in human neutrophils, which has major implications for the pathogenesis of CA-MRSA infections. PMID:20072612

  18. Increased Susceptibility of Humanized NSG Mice to Panton-Valentine Leukocidin and Staphylococcus aureus Skin Infection

    PubMed Central

    Tseng, Ching Wen; Kolar, Stacey L.; Müller, Sabrina; Rodriguez, Maria D.; Rezai-Zadeh, Kavon; Fan, Xuemo; Beenhouwer, David O.; Town, Terrence; Liu, George Y.

    2015-01-01

    Staphylococcus aureus is a leading cause of skin and soft-tissue infections worldwide. Mice are the most commonly used animals for modeling human staphylococcal infections. However a supra-physiologic S. aureus inoculum is required to establish gross murine skin pathology. Moreover, many staphylococcal factors, including Panton-Valentine leukocidin (PVL) elaborated by community-associated methicillin-resistant S. aureus (CA-MRSA), exhibit selective human tropism and cannot be adequately studied in mice. To overcome these deficiencies, we investigated S. aureus infection in non-obese diabetic (NOD)/severe combined immune deficiency (SCID)/IL2rγnull (NSG) mice engrafted with human CD34+ umbilical cord blood cells. These “humanized” NSG mice require one to two log lower inoculum to induce consistent skin lesions compared with control mice, and exhibit larger cutaneous lesions upon infection with PVL+ versus isogenic PVL- S. aureus. Neutrophils appear important for PVL pathology as adoptive transfer of human neutrophils alone to NSG mice was sufficient to induce dermonecrosis following challenge with PVL+ S. aureus but not PVL- S. aureus. PMX53, a human C5aR inhibitor, blocked PVL-induced cellular cytotoxicity in vitro and reduced the size difference of lesions induced by the PVL+ and PVL- S. aureus, but PMX53 also reduced recruitment of neutrophils and exacerbated the infection. Overall, our findings establish humanized mice as an important translational tool for the study of S. aureus infection and provide strong evidence that PVL is a human virulence factor. PMID:26618545

  19. Association of recurrent furunculosis with Panton-Valentine leukocidin and the genetic background of Staphylococcus aureus.

    PubMed

    Masiuk, Helena; Kopron, Katarzyna; Grumann, Dorothee; Goerke, Christiane; Kolata, Julia; Jursa-Kulesza, Joanna; Giedrys-Kalemba, Stefania; Bröker, Barbara M; Holtfreter, Silva

    2010-05-01

    Staphylococcus aureus is a major cause of skin and soft tissue infections, such as furuncles, carbuncles, and abscesses, but it also frequently colonizes the human skin and mucosa without causing clinical symptoms. Panton-Valentine leukocidin (PVL) is a pore-forming toxin that has been associated with soft tissue infections and necrotizing pneumonia. We have compared the genotypes, virulence gene repertoires, and phage patterns of 74 furunculosis isolates with those of 108 control strains from healthy nasal carriers. The large majority of furunculosis strains were methicillin sensitive. Clonal cluster (CC) 121 (CC121) and CC22 accounted for 70% of the furunculosis strains but for only 8% of the nasal isolates. The PVL-encoding genes luk-PV were detected in 85% of furunculosis strains, while their prevalence among colonizing S. aureus strains was below 1%. luk-PV genes were distributed over several lineages (CCs 5, 8, 22, 30, and 121 and sequence type 59). Even within the same lineages, luk-PV-positive phages characterized furunculosis strains, while their luk-PV-negative variants were frequent among nasal strains. The very tight epidemiological linkage between luk-PV and furunculosis, which could be separated from the genetic background of the S. aureus strain as well as from the gene makeup of the luk-PV-transducing phage, lends support to the notion of an important role for PVL in human furunculosis. These results make a case for the determination of luk-PV in recurrent soft tissue infections with methicillin-sensitive as well as methicillin-resistant S. aureus. PMID:20200289

  20. Panton-Valentine leukocidin positive Staphylococcal aureus infections of the head and neck: case series and brief review of literature.

    PubMed

    Hanratty, John; Changez, Huma; Smith, Andrew; Wales, Craig

    2015-04-01

    Panton-valentine leukocidin (PVL) is a pore-forming cytotoxin produced by some clones of Staphylococcus aureus that is associated with infections ranging from uncomplicated skin and soft tissue infections to life-threatening necrotizing pneumonia. PVL S aureus-associated maxillofacial infections are rarely reported; therefore, a high degree of clinical suspicion is warranted and close liaison with microbiologists and appropriate samples are required for optimal management. This report discusses the management and learning points from 3 such cases managed by the Greater Glasgow and Clyde National Health Service maxillofacial surgical teams. PMID:25544295

  1. Comment on “Symplectic integration of magnetic systems”: A proof that the Boris algorithm is not variational

    SciTech Connect

    Ellison, C. L.; Burby, J. W.; Qin, H.

    2015-11-01

    One popular technique for the numerical time advance of charged particles interacting with electric and magnetic fields according to the Lorentz force law [1], [2], [3] and [4] is the Boris algorithm. Its popularity stems from simple implementation, rapid iteration, and excellent long-term numerical fidelity [1] and [5]. Excellent long-term behavior strongly suggests the numerical dynamics exhibit conservation laws analogous to those governing the continuous Lorentz force system [6]. Moreover, without conserved quantities to constrain the numerical dynamics, algorithms typically dissipate or accumulate important observables such as energy and momentum over long periods of simulated time [6]. Identification of the conservative properties of an algorithm is important for establishing rigorous expectations on the long-term behavior; energy-preserving, symplectic, and volume-preserving methods each have particular implications for the qualitative numerical behavior [6], [7], [8], [9], [10] and [11].

  2. Comment on “Symplectic integration of magnetic systems”: A proof that the Boris algorithm is not variational

    DOE PAGESBeta

    Ellison, C. L.; Burby, J. W.; Qin, H.

    2015-11-01

    One popular technique for the numerical time advance of charged particles interacting with electric and magnetic fields according to the Lorentz force law [1], [2], [3] and [4] is the Boris algorithm. Its popularity stems from simple implementation, rapid iteration, and excellent long-term numerical fidelity [1] and [5]. Excellent long-term behavior strongly suggests the numerical dynamics exhibit conservation laws analogous to those governing the continuous Lorentz force system [6]. Moreover, without conserved quantities to constrain the numerical dynamics, algorithms typically dissipate or accumulate important observables such as energy and momentum over long periods of simulated time [6]. Identification of themore » conservative properties of an algorithm is important for establishing rigorous expectations on the long-term behavior; energy-preserving, symplectic, and volume-preserving methods each have particular implications for the qualitative numerical behavior [6], [7], [8], [9], [10] and [11].« less

  3. [Investigation of the presence of panton-valentin leucocidin (PVL) in Staphylococcus aureus strains isolated from clinical samples].

    PubMed

    Ozkul, Hilal; Oktem, I M Ali; Gülay, Zeynep

    2007-07-01

    Panton-Valentin leucocidin (PVL) is a cytotoxin which causes tissue necrosis by degradating leucocytes and other cell types. PVL has recently become very up to date as it has been shown to be the major virulance factor of community acquired methicillin resistant Staphylococcus aureus strains. In this study, the presence of PVL was investigated in methicillin sensitive and resistant S. aureus (MSSA and MRSA, respectively) strains which were isolated from clinical samples between January 2005-May 2006 at Dokuz Eylul University Hospital, Izmir. Fifty five MRSA and 79 MSSA strains which were isolated from blood, wound and respiratory tract samples were randomly included to the study. The presence of PVL was evaluated by multiplex polymerase chain reaction (PCR) which detects pvl and S. aureus-specific nuc genes. As a result, PVL positivities were detected in two (5%) of 40 MSSA and four (10.3%) of 39 MSSA strains isolated in the years 2005 and 2006, respectively. None of the MRSA isolates had pvl gene. Although this cytotoxin was rarely detected among MSSA isolates, it was interesting to note that the prevalence of PVL was twice more in the year 2006 compared to 2005. It was also worth to notify that four of six (66.7%) PVL positive strains had been isolated from the patients of general surgery inpatient or outpatient clinics. PMID:17933245

  4. High Prevalence of Panton-Valentine Leukocidin Among Methicillin-Sensitive Staphylococcus aureus Colonization Isolates in Rural Iowa

    PubMed Central

    Wardyn, Shylo E.; Forshey, Brett M.

    2012-01-01

    Recent studies have shown that livestock can carry Staphylococcus aureus and transmit it to human caretakers. We conducted a pilot study to determine the prevalence and molecular epidemiology of S. aureus among rural Iowans, including individuals with livestock contact. Nasal and throat swabs were collected and plated onto selective media to isolate methicillin-susceptible and methicillin-resistant S. aureus (MRSA), followed by antibiotic resistance testing and molecular analysis of the isolates. While no MRSA was detected, overall, 23.7% (31/131) of participants were found to harbor S. aureus in their nose, throat, or both. Fifteen isolates displayed resistance to one or more tested antibiotics, and the Panton-Valentine leukocidin (PVL) genes were present at a high level (29% [9/31] of S. aureus-positive participants). Younger age and tobacco use were associated with increased risk of S. aureus carriage. Our results suggest that carriage of PVL-positive S. aureus is common among rural Iowans, even in the absence of detectable MRSA colonization. PMID:22533373

  5. Necrotizing pneumonia due to clonally diverse Staphylococcus aureus strains producing Panton-Valentine leukocidin: the Czech experience.

    PubMed

    Rájová, J; Pantůček, R; Petráš, P; Varbanovová, I; Mašlaňová, I; Beneš, J

    2016-02-01

    A prospective study (2007-2013) was undertaken to investigate clinical features and prognostic factors of necrotizing pneumonia caused by Staphylococcus aureus producing Panton-Valentine leukocidin (PVL) in the Czech Republic. Twelve cases of necrotizing pneumonia were detected in 12 patients (median age 25 years) without severe underlying disease. Eight cases occurred in December and January and the accumulation of cases in the winter months preceding the influenza season was statistically significant (P < 0·001). The course of pneumonia was very rapid, leading to early sepsis and/or septic shock in all but one patient. Seven patients died and mortality was fourfold higher in those patients presenting with primary pneumonia than with pneumonia complicating other staphylococcal/pyogenic infection elsewhere in the body. The S. aureus isolates displayed considerable genetic variability and were assigned to five lineages CC8 (n = 3), CC15 (n = 2), CC30 (n = 2), CC80 (n = 1), and CC121 (n = 3) and one was a singleton of ST154 (n = 1), all were reported to be associated with community-acquired infection. Four strains were methicillin resistant. The high case-fatality rate can only be reduced by improving the speed of diagnosis and a rapid test to detect S. aureus in the airways is needed. PMID:26201459

  6. High prevalence of Panton-Valentine leukocidin among methicillin-sensitive Staphylococcus aureus colonization isolates in rural Iowa.

    PubMed

    Wardyn, Shylo E; Forshey, Brett M; Smith, Tara C

    2012-08-01

    Recent studies have shown that livestock can carry Staphylococcus aureus and transmit it to human caretakers. We conducted a pilot study to determine the prevalence and molecular epidemiology of S. aureus among rural Iowans, including individuals with livestock contact. Nasal and throat swabs were collected and plated onto selective media to isolate methicillin-susceptible and methicillin-resistant S. aureus (MRSA), followed by antibiotic resistance testing and molecular analysis of the isolates. While no MRSA was detected, overall, 23.7% (31/131) of participants were found to harbor S. aureus in their nose, throat, or both. Fifteen isolates displayed resistance to one or more tested antibiotics, and the Panton-Valentine leukocidin (PVL) genes were present at a high level (29% [9/31] of S. aureus-positive participants). Younger age and tobacco use were associated with increased risk of S. aureus carriage. Our results suggest that carriage of PVL-positive S. aureus is common among rural Iowans, even in the absence of detectable MRSA colonization. PMID:22533373

  7. Patients with Panton-Valentine leukocidin positive Staphylococcus aureus infections run an increased risk of longer hospitalisation.

    PubMed

    Cupane, L; Pugacova, N; Berzina, D; Cauce, V; Gardovska, D; Miklaševics, E

    2012-01-01

    Staphylococcus aureus is a major cause of purulent infections. The spectrum of staphylococcal infections varies from mild superficial to invasive life-threatening diseases due to S. aureus ability to produce a wide range of virulence factors, including toxins. A prospective observational study was conducted in the Children Clinical University Hospital in Riga, Latvia. During a period of sixteen months from November 2006 to March 2008 224 S. aureus isolates were collected. Our study revealed that Panton-Valentine leukocidine (PVL) genes are carried by a high number (75%) of S. aureus isolates recovered from children hospitalised in the Children Clinical University hospital. Most of these isolates were associated with abscesses and other skin and soft tissue infections. Patients with PVL positive invasive infections stayed significantly longer in hospital than patients with PVL negative invasive infections. Clonal distribution of PVL positive S. aureus isolates were closely related, which provides evidence for the wide spread of PVL producing spa type t435 and ST121 staphylococci in community. PMID:22493751

  8. Differential Distribution and Expression of Panton-Valentine Leucocidin among Community-Acquired Methicillin-Resistant Staphylococcus aureus Strains

    PubMed Central

    Saïd-Salim, Battouli; Mathema, Barun; Braughton, Kevin; Davis, Stacy; Sinsimer, Daniel; Eisner, William; Likhoshvay, Yekaterina; DeLeo, Frank R.; Kreiswirth, Barry N.

    2005-01-01

    Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is an emerging threat worldwide. CA-MRSA strains differ from hospital-acquired MRSA strains in their antibiotic susceptibilities and genetic backgrounds. Using several genotyping methods, we clearly define CA-MRSA at the genetic level and demonstrate that the prototypic CA-MRSA strain, MW2, has spread as a homogeneous clonal strain family that is distinct from other CA-MRSA strains. The Panton-Valentine leucocidin (PVL)-encoding genes, lukF and lukS, are prevalent among CA-MRSA strains and have previously been associated with CA-MRSA infections. To better elucidate the role of PVL in the pathogenesis of CA-MRSA, we first analyzed the distribution and expression of PVL among different CA-MRSA strains. Our data demonstrate that PVL genes are differentially distributed among CA-MRSA strains and, when they are present, are always transcribed, albeit with strain-to-strain variability of transcript levels. To directly test whether PVL is critical for the pathogenesis of CA-MRSA, we evaluated the lysis of human polymorphonuclear leukocytes (PMNs) during phagocytic interaction with PVL-positive and PVL-negative CA-MRSA strains. Unexpectedly, there was no correlation between PVL expression and PMN lysis, suggesting that additional virulence factors underlie leukotoxicity and, thus, the pathogenesis of CA-MRSA. PMID:16000462

  9. High frequency of Panton-Valentine leukocidin in Staphylococcus aureus causing pediatric infections in the city of Cartagena-Colombia.

    PubMed

    Correa-Jiménez, Oscar; Pinzón-Redondo, Hernando; Reyes, Niradiz

    2016-01-01

    Panton-Valentine leucocidin (PVL) is a pore-forming toxin that has been epidemiologically associated with CA-MRSA infections. However, its role in the pathogenicity of Staphylococcus aureus is still unclear. We evaluated the prevalence of PVL-coding genes in methicillin-resistant (MRSA) and methicillin-sensitive (MSSA) isolates that cause infections in pediatric patients in the city of Cartagena, Colombia. We obtained S. aureus isolates from patients at the Napoleon Franco Pareja Children's Hospital in Cartagena. Then, we evaluated the presence of the nuc, mecA, and PVL genes in these isolates by multiplex PCR and determined the antibiotic susceptibility profiles using CLSI standards. We further correlated methicillin susceptibility and the presence of PVL genes with clinical variables. Overall PVL prevalence in S. aureus isolates was 73.91%, with a frequency of 80.92% among MRSA isolates and 67.59% among MSSA. We found a correlation between erythromycin resistance and lack of PVL and found that PVL+ cases were more common in older patients. We found a high PVL prevalence in both MRSA and MSSA isolates, in concordance with previous regional reports. PMID:26631434

  10. Crystallochemical effects of heat treatment on Fe-dominant tourmalines from Dolní Bory (Czech Republic) and Vlachovo (Slovakia)

    NASA Astrophysics Data System (ADS)

    Bačík, P.; Ozdín, D.; Miglierini, M.; Kardošová, P.; Pentrák, M.; Haloda, J.

    2011-09-01

    Heat treatment was performed on selected Fe-dominant tourmalines to establish the nature of any change in optical properties. Two tourmaline samples from Dolní Bory, Czech Republic (TDB) and Vlachovo, Slovakia (TVL) were heated at 450, 700 and 900°C at 0.1 mPa and ambient oxidation conditions for 8 h. EMPA study shows that tourmaline from Vlachovo has schorlitic composition and tourmaline from Dolní Bory is alkali-depleted schorl to foitite. Although the black colour remained unchanged after heating at 450°C, it changed to brown at 700°C and reddish brown at 900°C. No significant changes of chemical composition were observed during heating. X-ray diffraction, infrared and Mössbauer study showed negligible oxidation of tourmaline heated at 450°C, but a significant change in iron valency state and deprotonization at 700°C. The oxidation of Fe is the main cause of tourmaline colour change, and the substitution vector for oxidation of Fe is Fe3+OFe{-1/2+}(OH)-1. The predicted deprotonization of OH was confirmed by infrared spectroscopy, which documented a decrease in OH groups in both samples, mainly at the V site. The oxidation of Fe is mostly significant in the Y site as documented on the compression of the Y-site octahedra and subsequent decrease in the a lattice parameter. This feature is consistent with lattice dimensions in the transition from schorl and foitite dimensions to those consistent with fluor-buergerite. The Z-site octahedra did not compressed and were not affected by heating-induced Fe oxidation, which indicates only negligible content of Z Fe2+ in original samples. After heating at 900°C, the tourmaline structure collapsed likely due to the thermally induced weakening of bonds in Y and Z octahedra, which results in amorphization of tourmaline. Subsequently, breakdown products including Fe-oxides and mullite replaced alkali-depleted amorphized tourmaline.

  11. The role of the Panton-Valentine leucocidin toxin in staphylococcal disease: a systematic review and meta-analysis

    PubMed Central

    Shallcross, Laura J; Fragaszy, Ellen; Johnson, Anne M; Hayward, Andrew C

    2013-01-01

    Summary Background Invasive community-onset staphylococcal disease has emerged worldwide associated with Panton-Valentine leucocidin (PVL) toxin. Whether PVL is pathogenic or an epidemiological marker is unclear. We investigate the role of PVL in disease, colonisation, and clinical outcome. Methods We searched Medline and Embase for original research reporting the prevalence of PVL genes among Staphylococcus aureus pneumonia, bacteraemia, musculoskeletal infection, skin and soft-tissue infection, or colonisation published before Oct 1, 2011. We calculated odds ratios (ORs) to compare patients with PVL-positive colonisation and each infection relative to the odds of PVL-positive skin and soft-tissue infection. We did meta-analyses to estimate odds of infection or colonisation with a PVL-positive strain with fixed-effects or random-effects models, depending on the results of tests for heterogeneity. Results Of 509 articles identified by our search strategy, 76 studies from 31 countries met our inclusion criteria. PVL strains are strongly associated with skin and soft-tissue infections, but are comparatively rare in pneumonia (OR 0·37, 95% CI 0·22–0·63), musculoskeletal infections (0·44, 0·19–0·99), bacteraemias (0·10, 0·06–0·18), and colonising strains (0·07, 0·01–0·31). PVL-positive skin and soft-tissue infections are more likely to be treated surgically than are PVL-negative infections, and children with PVL-positive musculoskeletal disease might have increased morbidity. For other forms of disease we identified no evidence that PVL affects outcome. Interpretation PVL genes are consistently associated with skin and soft-tissue infections and are comparatively rare in invasive disease. This finding challenges the view that PVL mainly causes invasive disease with poor prognosis. Population-based studies are needed to define the role of PVL in mild, moderate, and severe disease and to inform control strategies. Funding None. PMID:23103172

  12. Can Panton Valentine Leukocidin Gene And Clindamycin Susceptibility Serve As Predictors of Community Origin of MRSA From Skin and Soft Tissue Infections?

    PubMed Central

    Shashindran, Nandita; Nagasundaram, Niveditha; Thappa, Devinder Mohan

    2016-01-01

    Introduction Community associated Methicillin-resistant Staphylococcus aureus (CA-MRSA) strains have begun to replace Hospital Associated MRSA (HA-MRSA) strains in hospital settings all over the world. With the epidemiological distinctions between these strains beginning to become ill-defined, the categorisation of a strain as CA-MRSA or HA-MRSA is dependent on molecular methods to detect the presence of SCCmec (Staphylococcal Cassette Chromosome mec) elements. However other markers like the presence of Panton Valentine Leukocidin toxin (pvl) genes or Clindamycin susceptibility may also be associated with community origin of MRSA. Aim To determine the prevalence of CA-MRSA among MRSA strains isolated from skin and soft tissue infections and to evaluate the usefulness of Panton Valentine Leukocidin and Clindamycin susceptibility as markers of community origin of MRSA. Materials and Methods One hundred isolates of MRSA from skin and soft tissue were studied for the presence of SCCmec IV and V genes and Panton valentine leukocidin gene by Polymerase chain reaction. Inducible clindamycin resistance was screened for using the D-test. Statistical analysis used Fischer’s exact test. A p-value <0.05 was considered significant Results Eighteen out of 100 MRSA strains were found to be CA-MRSA based on presence of SCCmecV. The proportion of Panton Valentine Leukocidin gene carriage among CA- MRSA as compared to HA-MRSA was found to be statistically significant (p<0.0001). Among the CA-MRSA strains, 94.4% were found to be susceptible to Clindamycin as against only 13.4% of the HA-MRSA strains (p<0.0001). The odds of an MRSA strain being CA-MRSA if it was both Clindamycin susceptible and PVL gene positive was calculated to be 68.25 (p<0.0001). Conclusion Both Clindamycin susceptibility and pvl gene carriage were found to be independent predictors of community origin of MRSA, but taken together the association was highly significant. PMID:26894063

  13. Recurrent skin infection associated with nasal carriage of Panton-Valentine leukocidin-positive methicillin-susceptible Staphylococcus aureus closely related to the EMRSA-15 clone.

    PubMed

    Vignaroli, Carla; Di Sante, Laura; Stano, Paola; Varaldo, Pietro E; Camporese, Alessandro

    2016-01-01

    We report the case of a soldier with recurrent skin infection associated with nasal carriage of a Panton-Valentine leukocidin (PVL)-producing methicillin-susceptible Staphylococcus aureus (MSSA), closely related to the EMRSA-15 clone. MSSA isolates causing infection not requiring hospitalization usually go unnoticed; however, their typing may be useful to understand the global distribution of successful staphylococcal lineages related to epidemic clones. PVL-positive MSSA strains might serve as reservoirs from which virulent methicillin-resistant strains may evolve and spread. PMID:26674061

  14. The life, achievements and legacy of a great Canadian investigator: Professor Boris Petrovich Babkin (1877-1950).

    PubMed

    Beck, Ivan T

    2006-09-01

    The present paper reviews the life and achievements of Professor Boris Petrovich Babkin (MD DSc LLD). History is only worth writing about if it teaches us about the future; therefore, this historical review concludes by describing what today's and future gastrointestinal physiologists could learn from Dr Babkin's life. Dr Babkin was born in Russia in 1877. He graduated with an MD degree from the Military Medical Academy in St Petersburg, Russia, in 1904. Not being attracted to clinical practice, and after some hesitation concerning whether he would continue in history or basic science of medicine, he entered the laboratory of Professor Ivan Petrovich Pavlov. Although he maintained an interest in history, in Pavlov's exciting environment he became fully committed to physiology of the gastrointestinal system. He advanced quickly in Russia and was Professor of Physiology at the University of Odessa. In 1922, he was critical of the Bolshevik revolution, and after a short imprisonment, he was ordered to leave Russia. He was invited with his family by Professor EH Starling (the discoverer of secretin) to his department at University College, London, England. Two years later, he was offered a professorship in Canada at Dalhousie University, Halifax, Nova Scotia. After contributing there for four years, he joined McGill University, Montreal, Quebec, in 1928 as Research Professor. He remained there for the rest of his career. Between 1940 and 1941, he chaired the Department, and following retirement, he remained as Research Professor. At the invitation of the world-famous neurosurgeon, Wilder Penfield, Dr Babkin continued as Research Fellow in the Department of Neurosurgery until his death in 1950 at age 73. His major achievements were related to establishing the concept of brain-gut-brain interaction and the influence of this on motility, as well as on interface of multiple different cells, nerves and hormones on secretory function. He had a major role in the rediscovery

  15. The life, achievements and legacy of a great Canadian investigator: Professor Boris Petrovich Babkin (1877–1950)

    PubMed Central

    Beck, Ivan T

    2006-01-01

    The present paper reviews the life and achievements of Professor Boris Petrovich Babkin (MD DSc LLD). History is only worth writing about if it teaches us about the future; therefore, this historical review concludes by describing what today’s and future gastrointestinal physiologists could learn from Dr Babkin’s life. Dr Babkin was born in Russia in 1877. He graduated with an MD degree from the Military Medical Academy in St Petersburg, Russia, in 1904. Not being attracted to clinical practice, and after some hesitation concerning whether he would continue in history or basic science of medicine, he entered the laboratory of Professor Ivan Petrovich Pavlov. Although he maintained an interest in history, in Pavlov’s exciting environment he became fully committed to physiology of the gastrointestinal system. He advanced quickly in Russia and was Professor of Physiology at the University of Odessa. In 1922, he was critical of the Bolshevik revolution, and after a short imprisonment, he was ordered to leave Russia. He was invited with his family by Professor EH Starling (the discoverer of secretin) to his department at University College, London, England. Two years later, he was offered a professorship in Canada at Dalhousie University, Halifax, Nova Scotia. After contributing there for four years, he joined McGill University, Montreal, Quebec, in 1928 as Research Professor. He remained there for the rest of his career. Between 1940 and 1941, he chaired the Department, and following retirement, he remained as Research Professor. At the invitation of the world-famous neurosurgeon, Wilder Penfield, Dr Babkin continued as Research Fellow in the Department of Neurosurgery until his death in 1950 at age 73. His major achievements were related to establishing the concept of brain-gut-brain interaction and the influence of this on motility, as well as on interface of multiple different cells, nerves and hormones on secretory function. He had a major role in the

  16. Infective Endocarditis Caused by Panton-Valentine Leukocidin-producing Methicillin-susceptible Staphylococcus aureus Identified by the Broad-range PCR Method.

    PubMed

    Nakajima, Hiroshi; Dohi, Kaoru; Tanabe, Masaki; Nakamura, Akiko; Kanemitsu, Shinji; Wada, Hideo; Yamada, Norikazu; Nobori, Tsutomu; Shinpo, Hideto; Ito, Masaaki

    2016-01-01

    A 76-year-old man was admitted to a community hospital due to a persistent high fever. He became afebrile after the administration of broad-spectrum antibiotics, but developed heart failure due to progressive aortic and mitral valve insufficiency and was transferred to our hospital. Although sequential blood cultures were negative, a broad-range polymerase chain reaction targeting the bacterial 16S-rRNA gene followed by the direct sequencing of whole blood revealed spa(+), mecA(-) and Panton-Valentine leukocidin (PVL)(+). He was finally diagnosed with infective endocarditis (IE) caused by PVL-producing methicillin-susceptible Staphylococcus aureus (MSSA), and underwent cardiac surgery. This is the first reported case of IE due to MSSA producing PVL. PMID:27432095

  17. First report of Panton-Valentine leukocidin-positive methicillin-susceptible Staphylococcus aureus ST88 harbouring ΦSa2usa isolated from refractory breast abscesses in Japan.

    PubMed

    Togashi, A; Aung, M S; Yoto, Y; Akane, Y; Tsugawa, T; Kawaguchiya, M; Tsutsumi, H; Kobayashi, N

    2016-09-01

    A methicillin-susceptible Staphylococcus aureus with Panton-Valentine leukocidin (PVL) genes was isolated from refractory breast abscesses of 12-year-old girl in Japan, and classified into ST88, spa-t1245 and coa-IIIa. This strain harboured PVL phage ΦSa2usa, which is usually found in ST8 community-acquired methicillin-resistant S. aureus clone USA300. PMID:27453786

  18. In Vivo Efficacy of Ceftaroline Fosamil in a Methicillin-Resistant Panton-Valentine Leukocidin-Producing Staphylococcus aureus Rabbit Pneumonia Model

    PubMed Central

    Hayez, Davy; Da Silva, Sonia; Labrousse, Delphine; Biek, Donald; Badiou, Cedric; Dumitrescu, Oana; Guerard, Pascal; Charles, Pierre-Emmanuel; Piroth, Lionel; Lina, Gerard; Vandenesch, Francois; Chavanet, Pascal

    2014-01-01

    Ceftaroline, the active metabolite of the prodrug ceftaroline fosamil, is a cephalosporin with broad-spectrum in vitro activity against Gram-positive organisms, including methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Streptococcus pneumoniae (MDRSP), and common Gram-negative pathogens. This study investigated the in vivo activity of ceftaroline fosamil compared with clindamycin, linezolid, and vancomycin in a severe pneumonia model due to MRSA-producing Panton-Valentine leukocidin (PVL). A USA300 PVL-positive clone was used to induce pneumonia in rabbits. Infected rabbits were randomly assigned to no treatment or simulated human-equivalent dosing with ceftaroline fosamil, clindamycin, linezolid, or vancomycin. Residual bacterial concentrations in the lungs and spleen were assessed after 48 h of treatment. PVL expression was measured using a specific enzyme-linked immunosorbent assay (ELISA). Ceftaroline, clindamycin, and linezolid considerably reduced mortality rates compared with the control, whereas vancomycin did not. Pulmonary and splenic bacterial titers and PVL concentrations were greatly reduced by ceftaroline, clindamycin, and linezolid. Ceftaroline, clindamycin, and linezolid were associated with reduced pulmonary tissue damage based on significantly lower macroscopic scores. Ceftaroline fosamil, clindamycin, and, to a lesser extent, linezolid were efficient in reducing bacterial titers in both the lungs and spleen and decreasing macroscopic scores and PVL production compared with the control. PMID:24395236

  19. Detection of stapylococcal enterotoxin, methicillin-resistant and Panton-Valentine leukocidin genes in coagulase-negative staphylococci isolated from cows and ewes with subclinical mastitis.

    PubMed

    Unal, Nilgün; Cinar, Oya Doğu

    2012-02-01

    Coagulase-negative staphylococci (CNS) are the most prevalent mastitis pathogens. However, virulence characteristics of CNS have not been well determined. The presence of genes for enterotoxins (sea-sej), toxic shock syndrome toxin-1 (tst), the exfoliative toxins (eta, etb), Panton-Valentine leukocidin (pvl) and mecA of CNS species isolated from cows and ewes with subclinical mastitis was investigated in this study. A total of 121 CNS (81 cows, 40 ewes) representing 18 different Staphylococci species were examined by PCR, and 38.1% (33 cows and 13 ewes) of CNS isolates had one or more se genes. The difference between percentages for SE toxin genes of CNS strains isolated from cows (40.7%) and ewes (32.5%) was not statistically significant (P > 0.05; χ(2) = 0.380). It was found that S. simulans isolates had the highest prevalent se genes. Furthermore, the most common SE gene types was seh-sej. In this study, none of the isolates harbored the toxic shock syndrome toxin gene (tsst) and the exfoliative toxin genes (eta, etb). Five cow (6.17%) and three ewe CNS (7.5%) isolates had mecA gene. Three cow (3.7%) and two ewe CNS (5.0%) isolates had pvl gene. In conclusion, the present study showed that CNS species isolated from cows and ewes could serve as potential reservoir of se, mecA, and pvl genes. PMID:22160510

  20. Evaluation of the R-Biopharm RIDA®GENE Panton-Valentine leukocidin (PVL) kit for the detection of Staphylococcus aureus PVL from pus samples.

    PubMed

    Bouchiat, C; Bes, M; Bouveyron, C; Vandenesch, F; Tristan, A

    2015-09-01

    Staphylococcus aureus Panton-Valentine leukocidin (PVL) is associated with primary skin and soft-tissue infections (SSTI). We aimed to divert the RIDA®GENE PVL kit (RBiopharm) from its intended use on cultures to the detection of PVL-encoding genes directly from pus samples. Performance was compared with that of the in-house PCR method developed by the French National Reference Centre for Staphylococci. From June 2013 to May 2014, pus samples from S. aureus SSTI were tested. Our in-house PCR was performed on parallel cultures as the gold standard, while the RIDA®GENE PVL assay was used directly on pus samples from the sterile container, or a swab or an Eswab previously dipped in the pus. The kit specificity was also evaluated with pus samples that grew Streptococcus pyogenes. S. aureus reference strains harboring PVL-encoding genes, including known polymorphisms, were also tested. A total of 56 S. aureus-containing pus samples (28 PVL + and 28 PVL-) were collected and analyzed. Sensitivity and specificity of the commercial kit were 96.4 % and 100 % respectively, with equal performance whether tested directly from the sterile container or the Eswab. Sensitivity was lower (67.9 %) when the test was performed from a regular SSTI swab. None of the Streptococcus pyogenes pus samples scored positive (n = 5). Specificity was assessed using reference strains (n = 14); in all strains the PVL gene was correctly detected. This study identified the RIDA®GENE PVL kit as an efficient, sensitive, and specific tool for the rapid detection of PVL-encoding genes in pus samples. PMID:26139561

  1. Staphylococcus aureus Isolates Carrying Panton-Valentine Leucocidin Genes: Their Frequency, Antimicrobial Patterns, and Association With Infectious Disease in Shahrekord City, Southwest Iran

    PubMed Central

    Shariati, Laleh; Validi, Majid; Hasheminia, Ali Mohammad; Ghasemikhah, Reza; Kianpour, Fariborz; Karimi, Ali; Nafisi, Mohammad Reza; Tabatabaiefar, Mohammad Amin

    2016-01-01

    Background: A diversity of virulence factors work together to create the pathogenicity of Staphylococcus aureus. These factors include cell surface components that promote adherence to surfaces as well as exoproteins such as Panton-Valentine leukocidin (PVL), encoded by the luk-PV genes, that invade or bypass the immune system and are toxic to the host, thereby enhancing the severity of infections caused by methicillin-resistant Staphylococcus aureus (MRSA). Objectives: The aim of this study was to determine the frequency of PVL-positive MRSA strains by real-time PCR and their antibiotic susceptibility patterns by phenotypic test. Materials and Methods: In total, 284 Staphylococcus isolates, identified by phenotypic methods from clinical samples of Shahrekord University Hospitals, Shahrekord, Iran, were tested for nuc, mecA, and PVL genes by TaqMan real-time PCR. The antibiotic susceptibility patterns of PVL-containing MRSA strains were determined via the disk diffusion method. Results: In total, 196 isolates (69%) were nuc positive (i.e., S. aureus); of those isolates, 96 (49%) were mecA positive (MRSA). Eighteen (18.8%) of the 96 MRSA positive and 3 (3%) of the 100 methicillin-susceptible Staphylococcus aureus (MSSA) strains were PVL positive. PVL-positive MRSA strains were mostly recovered from tracheal specimens. Eight PVL-positive MRSA strains were resistant to all the tested antibiotics except vancomycin. A significant correlation (P = 0.001) was found between the mecA positivity and the presence of luk-PV genes. Conclusions: Community acquired (CA)-MRSA is becoming a public health concern in many parts of the world, including Asian countries. The variable prevalence of luk-PV-positive MRSA isolates in different regions and their rather high frequency in pneumonia necessitate the application of rapid diagnostic methods such as real-time PCR to improve treatment effectiveness. PMID:27099685

  2. Kineret®/IL-1ra Blocks the IL-1/IL-8 Inflammatory Cascade during Recombinant Panton Valentine Leukocidin-Triggered Pneumonia but Not during S. aureus Infection

    PubMed Central

    Hayez, Davy; Da Silva, Sonia; Badiou, Cédric; Couzon, Florence; Bes, Michèle; Chavanet, Pascal; Lina, Gérard; Vandenesch, François; Croisier-Bertin, Delphine; Henry, Thomas

    2014-01-01

    Objectives Community-acquired Staphylococcus aureus necrotizing pneumonia is a life-threatening disease. Panton Valentine Leukocidin (PVL) has been associated with necrotizing pneumonia. PVL triggers inflammasome activation in human macrophages leading to IL-1β release. IL-1β activates lung epithelial cells to release IL-8. This study aimed to assess the relevance of this inflammatory cascade in vivo and to test the potential of an IL-1 receptor antagonist (IL-1Ra/Kineret) to decrease inflammation-mediated lung injury. Methods We used the sequential instillation of Heat-killed S. aureus and PVL or S. aureus infection to trigger necrotizing pneumonia in rabbits. In these models, we investigated inflammation in the presence or absence of IL-1Ra/Kineret. Results We demonstrated that the presence of PVL was associated with IL-1β and IL-8 release in the lung. During PVL-mediated sterile pneumonia, Kineret/IL-1Ra reduced IL-8 production indicating the relevance of the PVL/IL-1/IL-8 cascade in vivo and the potential of Kineret/IL-1Ra to reduce lung inflammation. However, Kineret/IL-1Ra was ineffective in blocking IL-8 production during infection with S. aureus. Furthermore, treatment with Kineret increased the bacterial burden in the lung. Conclusions Our data demonstrate PVL-dependent inflammasome activation during S.aureus pneumonia, indicate that IL-1 signaling controls bacterial burden in the lung and suggest that therapy aimed at targeting this pathway might be deleterious during pneumonia. PMID:24905099

  3. Co-detection of Panton-Valentine leukocidin encoding genes and cotrimoxazole resistance in Staphylococcus aureus in Gabon: implications for HIV-patients’ care

    PubMed Central

    Kraef, Christian; Alabi, Abraham S.; Peters, Georg; Becker, Karsten; Kremsner, Peter G.; Rossatanga, Elie G.; Mellmann, Alexander; Grobusch, Martin P.; Zanger, Philipp; Schaumburg, Frieder

    2015-01-01

    Patients infected with the human immunodeficiency virus (HIV) are frequently exposed to antimicrobial agents. This might have an impact on the resistance profile, genetic background and virulence factors of colonizing Staphylococcus aureus. Sub-Saharan Africa is considered to be endemic for Panton-Valentine leukocidin (PVL) positive S. aureus which can be associated with skin and soft tissue infections (SSTI). We compared S. aureus from nasal and pharyngeal swabs from HIV patients (n = 141) and healthy controls (n = 206) in Gabon in 2013, and analyzed determinants of colonization with PVL positive isolates in a cross-sectional study. S. aureus isolates were screened for the presence of selected virulence factors (incl. PVL) and were subjected to antimicrobial susceptibility testing and genotyping. In HIV patients, S. aureus was more frequently detected (36.9 vs. 31.6%) and the isolates were more frequently PVL positive than in healthy controls (42.1 vs. 23.2%). The presence of PVL was associated with cotrimoxazole resistance (OR = 25.1, p < 0.001) and the use of cotrimoxazole was a risk factor for colonization with PVL positive isolates (OR = 2.5, p = 0.06). PVL positive isolates were associated with the multilocus sequence types ST15 (OR = 5.6, p < 0.001) and ST152 (OR = 62.1, p < 0.001). Participants colonized with PVL positive isolates reported more frequently SSTI in the past compared to carriers of PVL negative isolates (OR = 2.7, p = 0.01). In conclusion, the novelty of our study is that cotrimoxazole might increase the risk of SSTI in regions where cotrimoxazole resistance is high and associated with PVL. This finding needs to be confirmed in prospective studies. PMID:25699036

  4. Molecular epidemiologic study of community-associated methicillin-resistant Staphylococcus aureus with Panton-Valentine leukocidin gene among family members in Japan.

    PubMed

    Uehara, Yuki; Ito, Teruyo; Ogawa, Yu; Hirotaki, Shintaro; Shoji, Takayo; Tame, Tomoyuki; Horikoshi, Yuho; Hiramatsu, Keiichi

    2015-09-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is one of the worldwide concerns of antimicrobial chemotherapy. An accumulation of ten patients in five families (A-E) suffering from skin and soft tissue infection (SSTI) of CA-MRSA was experienced in 2012, in Fuchu-shi, Tokyo, Japan. Molecular epidemiological investigation was performed for the 10 MRSA strains obtained from 8 children and 2 of their parents to assess endemic patterns of CA-MRSA in the community. Results of molecular typing, presence of toxin genes and antimicrobial susceptibilities were analyzed combined with the patients' clinical information. Each family had its own unique MRSA strain: A, ST30-SCCmec IVd; B, ST8-SCCmec IVd; C, ST8-SCCmec IVa; D, ST8-SCCmec IVl; E, ST8-SCCmec IVl and ST858-SCCmec IVl. Seven strains from the families A-C carried Panton-Valentine leukocidin gene. Three strains from the families D and E carried toxic shock syndrome toxin gene. Strains belonged to the same family demonstrated genetically related banding patterns of pulsed-filed gel electrophoresis. The family C experienced intrafamilial transmission of USA300-0114. Our data showed the MRSA clones disseminating in this community were highly diverse. They contained USA300-0114 clone, the rapidly distributing clone in the world, as well as MRSA clones identified in Japan. Our results suggested intrafamilial transmission of MRSA could be initial phenomenon of wide transmission in a community, therefore CA-MRSA SSTI in children and their family members should be monitored closely in order to notice the spread of highly pathogenic and transmittable strains. PMID:26091885

  5. Prevalence of Panton-Valentine leucocidin and phenotypic and genotypic characterization of biofilm formation among Staphylococcus aureus strains isolated from children with adenoid hypertrophy.

    PubMed

    Emaneini, Mohammad; Khoramrooz, Seyed Sajjad; Shahsavan, Shadi; Dabiri, Hossein; Jabalameli, Fereshteh

    2015-12-01

    Adenoids as a first line of host defense against respiratory microbes play an important role in majority of upper airway infectious and noninfectious illnesses. Bacterial pathogen can colonize on the adenoid tissue and probably act as a reservoir for them. To determine phenotypic and genotypic characterization of biofilm forming capacity of Staphylococcus aureus isolates from children with adenoid hypertrophy and prevalence of Panton-Valentine leukocidin (PVL) gene we collected 17 consecutive, clinically significant S. aureus isolates from children with adenoid hypertrophy undergoing adenoidectomy with one or more of the upper airway obstruction symptoms, nasal obstruction, mouth breathing, snoring, or sleep apnea. Biofilm formation was evaluated by colorimetric microtiter plate's assay. Gene encoding PVL and adhesion- or biofilm formation-encoding genes were targeted by polymerase chain reaction (PCR) assay. According to the results, all strains produced biofilm. Seven (41.2%) isolates produced strong biofilm whereas 7 (41.2%) isolates produced week and 3 (17.6%) isolates produced medium biofilm. Regarding the adhesion- or biofilm formation-encoding genes, 16 (94.1%) isolates were positive for the gene eno, 13(76.4%) for icaA, 13 (76.4%) for icaD, 10 (58.8%) for fib, 10 (58.8%) for fnbB, 4(23.5%) for can, and 1(5.8%) for fnbA. The high prevalence of genes encoding biofilms and adhesins and phenotypic ability to form a biofilm by S. aureus strains emphasizes the pathogenic character of strains isolated from children with adenoid hypertrophy. PMID:26476288

  6. Methicillin-Resistant Staphylococcus aureus Isolated From Various Types of Hospital Infections in Pediatrics: Panton-Valentine Leukocidin, Staphylococcal Chromosomal Cassette mec SCCmec Phenotypes and Antibiotic Resistance Properties

    PubMed Central

    Dormanesh, Banafshe; Siroosbakhat, Soheila; Khodaverdi Darian, Ebrahim; Afsharkhas, Ladan

    2015-01-01

    Background: Staphylococcus aureus has long been considered as a major pathogen of hospital infections. Objectives: The present investigation was carried out to study the distribution of Staphylococcal Chromosomal Cassette mec (SCCmec) types, Panton-Valentine Leukocidin (PVL) gene and antibiotic resistance properties of Methicillin Resistant Staphylococcus aureus (MRSA) strains isolated from various types of infections found in Iranian pediatric patients. Patients and Methods: Two-hundred and fifty-five clinical specimens were collected from four major provinces of Iran. Samples were cultured and the MRSA strains were subjected to Polymerase Chain Reaction (PCR). The patterns of antibiotic resistance were determined using the disk diffusion method. Results: Seventy-four out of 255 (29.01%) clinical samples were positive for MRSA. Of the 74 MRSA strains, 47 (63.51%) were PVL positive. The clinical samples of respiratory tract infections (36.36%), those from the Shiraz province (37.87%) and samples collected during the summer season (56.48%) were the most commonly infected samples. The most commonly detected antibiotic resistance genes were tetK (89.18%), mecA (71.62%), msrA (56.75%) and tetM (54.05%). Methicillin Resistant Staphylococcus aureus had the highest levels of resistance against penicillin (100%), tetracycline (98.64%), ampicillin (93.24%) and oxacillin (93.24%). The most commonly detected SCCmec types in the MRSA strains were type V (18.91%) and III (17.56%). Conclusions: Regular surveillance of hospital-associated infections and monitoring of the antibiotic sensitivity patterns are required to reduce the prevalence of MRSA. We recommend initial management of children affected by MRSA with imipenem, lincomycin and cephalothin prescriptions. PMID:26862375

  7. β-Lactams Interfering with PBP1 Induce Panton-Valentine Leukocidin Expression by Triggering sarA and rot Global Regulators of Staphylococcus aureus ▿

    PubMed Central

    Dumitrescu, Oana; Choudhury, Priya; Boisset, Sandrine; Badiou, Cédric; Bes, Michele; Benito, Yvonne; Wolz, Christiane; Vandenesch, François; Etienne, Jerome; Cheung, Ambrose L.; Bowden, Maria Gabriela; Lina, Gerard

    2011-01-01

    Previous articles reported that beta-lactam antibiotics increase the expression of Staphylococcus aureus Panton-Valentine leukocidin (PVL) by activating its transcription. We investigated the mechanisms underlying the inductor effect of beta-lactams on PVL expression by determining targets and regulatory pathways possibly implicated in this process. We measured PVL production in the presence of oxacillin (nonselective), imipenem (penicillin-binding protein 1 [PBP1] selective), cefotaxime (PBP2 selective), cefaclore (PBP3 selective), and cefoxitin (PBP4 selective). In vitro, we observed increased PVL production consistent with luk-PV mRNA levels that were 20 to 25 times higher for community-acquired methicillin-resistant S. aureus (CA-MRSA) cultures treated with PBP1-binding oxacillin and imipenem than for cultures treated with other beta-lactams or no antibiotic at all. This effect was also observed in vivo, with increased PVL mRNA levels in lung tissues from CA-MRSA-infected mice treated with imipenem but not cefoxitin. To confirm the involvement of PBP1 inhibition in this pathway, PBP1 depletion by use of an inducible pbp1 antisense RNA showed a dose-dependent relationship between the level of pbp1 antisense RNA and the luk-PV mRNA level. Upon imipenem treatment of exponential-phase cultures, we observed an increased sarA mRNA level after 30 min of incubation followed by a decreased rot mRNA level after 1 to 4 h of incubation. Unlike the agr and saeRS positive regulators, which were nonessential for PVL induction by beta-lactams, the sarA (positive) and rot (negative) PVL regulators were necessary for PVL induction by imipenem. Our results suggest that antibiotics binding to PBP1 increase PVL expression by modulating sarA and rot, which are essential mediators of the inductor effect of beta-lactams on PVL expression. PMID:21502633

  8. The Association of Panton-Valentine leukocidin and mecA Genes in Methicillin-Resistant Staphylococcus aureus Isolates From Patients Referred to Educational Hospitals in Ahvaz, Iran

    PubMed Central

    Motamedi, Hossein; Rahmat Abadi, Seyyed Soheil; Moosavian, Seyyed Mojtaba; Torabi, Maryam

    2015-01-01

    Background: Staphylococcus aureus, an important human pathogen is one of the main causative agents of nosocomial infection. Virulence genes play a major role in the pathogenicity of this agent and its infections. Methicillin-Resistant Staphylococcus aureus (MRSA) isolates are major challenge among infectious agents that can cause severe infections and mortality. Methicillin-resistant S. aureus produces a unique type of Penicillin Binding Protein 2a (PBP2a) that has low affinity for β-lactam antibiotics. Most of the MRSA bacterial strains can also produce a leukotoxin as Panton-Valentine Leukocidin (PVL) that increases the virulence of MRSA strains and can cause severe necrotic pneumonia. The presence of pvl gene is a genetic marker for the MRSA populations. Objectives: The aim of this study was to explore the association of pvl and mecA genes in clinical isolates of MRSA. Materials and Methods: Fifty MRSA isolates were collected from 200 clinical samples from three different educational hospitals in Ahvaz, Iran, and identified by biochemical tests including catalase, oxidase, tube coagulase, mannitol fermentation, and sensitivity to furazolidone, resistance to bacitracin, PYR test and Voges-Proskauer test. Their resistance to methicillin was evaluated using the disc diffusion method. DNA was extracted by boiling and then the presence of pvl and mecA genes was investigated by the polymerase chain reaction method using specific primers. Results: The results revealed that mecA and pvl genes were positive for 15 (30%) and 3 (6%) of the isolates, respectively. None of mecA positive isolates was positive for pvl gene. Conclusions: It can be concluded from these results that fortunately the prevalence of pvl gene is low in MRSA isolates in this region and there is no association between the presence of pvl and mecA genes in these isolates. PMID:26468365

  9. Typing of Panton-Valentine Leukocidin-Encoding Phages and lukSF-PV Gene Sequence Variation in Staphylococcus aureus from China

    PubMed Central

    Zhao, Huanqiang; Hu, Fupin; Jin, Shu; Xu, Xiaogang; Zou, Yuhan; Ding, Baixing; He, Chunyan; Gong, Fang; Liu, Qingzhong

    2016-01-01

    Panton-Valentine leukocidin (PVL, encoded by lukSF-PV genes), a bi-component and pore-forming toxin, is carried by different staphylococcal bacteriophages. The prevalence of PVL in Staphylococcus aureus has been reported around the globe. However, the data on PVL-encoding phage types, lukSF-PV gene variation and chromosomal phage insertion sites for PVL-positive S. aureus are limited, especially in China. In order to obtain a more complete understanding of the molecular epidemiology of PVL-positive S. aureus, an integrated and modified PCR-based scheme was applied to detect the PVL-encoding phage types. Phage insertion locus and the lukSF-PV variant were determined by PCR and sequencing. Meanwhile, the genetic background was characterized by staphylococcal cassette chromosome mec (SCCmec) typing, staphylococcal protein A (spa) gene polymorphisms typing, pulsed-field gel electrophoresis (PFGE) typing, accessory gene regulator (agr) locus typing and multilocus sequence typing (MLST). Seventy eight (78/1175, 6.6%) isolates possessed the lukSF-PV genes and 59.0% (46/78) of PVL-positive strains belonged to CC59 lineage. Eight known different PVL-encoding phage types were detected, and Φ7247PVL/ΦST5967PVL (n = 13) and ΦPVL (n = 12) were the most prevalent among them. While 25 (25/78, 32.1%) isolates, belonging to ST30, and ST59 clones, were unable to be typed by the modified PCR-based scheme. Single nucleotide polymorphisms (SNPs) were identified at five locations in the lukSF-PV genes, two of which were non-synonymous. Maximum-likelihood tree analysis of attachment sites sequences detected six SNP profiles for attR and eight for attL, respectively. In conclusion, the PVL-positive S. aureus mainly harbored Φ7247PVL/ΦST5967PVL and ΦPVL in the regions studied. lukSF-PV gene sequences, PVL-encoding phages, and phage insertion locus generally varied with lineages. Moreover, PVL-positive clones that have emerged worldwide likely carry distinct phages. PMID:27536288

  10. Typing of Panton-Valentine Leukocidin-Encoding Phages and lukSF-PV Gene Sequence Variation in Staphylococcus aureus from China.

    PubMed

    Zhao, Huanqiang; Hu, Fupin; Jin, Shu; Xu, Xiaogang; Zou, Yuhan; Ding, Baixing; He, Chunyan; Gong, Fang; Liu, Qingzhong

    2016-01-01

    Panton-Valentine leukocidin (PVL, encoded by lukSF-PV genes), a bi-component and pore-forming toxin, is carried by different staphylococcal bacteriophages. The prevalence of PVL in Staphylococcus aureus has been reported around the globe. However, the data on PVL-encoding phage types, lukSF-PV gene variation and chromosomal phage insertion sites for PVL-positive S. aureus are limited, especially in China. In order to obtain a more complete understanding of the molecular epidemiology of PVL-positive S. aureus, an integrated and modified PCR-based scheme was applied to detect the PVL-encoding phage types. Phage insertion locus and the lukSF-PV variant were determined by PCR and sequencing. Meanwhile, the genetic background was characterized by staphylococcal cassette chromosome mec (SCCmec) typing, staphylococcal protein A (spa) gene polymorphisms typing, pulsed-field gel electrophoresis (PFGE) typing, accessory gene regulator (agr) locus typing and multilocus sequence typing (MLST). Seventy eight (78/1175, 6.6%) isolates possessed the lukSF-PV genes and 59.0% (46/78) of PVL-positive strains belonged to CC59 lineage. Eight known different PVL-encoding phage types were detected, and Φ7247PVL/ΦST5967PVL (n = 13) and ΦPVL (n = 12) were the most prevalent among them. While 25 (25/78, 32.1%) isolates, belonging to ST30, and ST59 clones, were unable to be typed by the modified PCR-based scheme. Single nucleotide polymorphisms (SNPs) were identified at five locations in the lukSF-PV genes, two of which were non-synonymous. Maximum-likelihood tree analysis of attachment sites sequences detected six SNP profiles for attR and eight for attL, respectively. In conclusion, the PVL-positive S. aureus mainly harbored Φ7247PVL/ΦST5967PVL and ΦPVL in the regions studied. lukSF-PV gene sequences, PVL-encoding phages, and phage insertion locus generally varied with lineages. Moreover, PVL-positive clones that have emerged worldwide likely carry distinct phages. PMID:27536288

  11. Multiplex Real-Time PCR for Detection of Staphylococcus aureus, mecA and Panton-Valentine Leukocidin (PVL) Genes from Selective Enrichments from Animals and Retail Meat

    PubMed Central

    Velasco, Valeria; Sherwood, Julie S.; Rojas-García, Pedro P.; Logue, Catherine M.

    2014-01-01

    The aim of this study was to compare a real-time PCR assay, with a conventional culture/PCR method, to detect S. aureus, mecA and Panton-Valentine Leukocidin (PVL) genes in animals and retail meat, using a two-step selective enrichment protocol. A total of 234 samples were examined (77 animal nasal swabs, 112 retail raw meat, and 45 deli meat). The multiplex real-time PCR targeted the genes: nuc (identification of S. aureus), mecA (associated with methicillin resistance) and PVL (virulence factor), and the primary and secondary enrichment samples were assessed. The conventional culture/PCR method included the two-step selective enrichment, selective plating, biochemical testing, and multiplex PCR for confirmation. The conventional culture/PCR method recovered 95/234 positive S. aureus samples. Application of real-time PCR on samples following primary and secondary enrichment detected S. aureus in 111/234 and 120/234 samples respectively. For detection of S. aureus, the kappa statistic was 0.68–0.88 (from substantial to almost perfect agreement) and 0.29–0.77 (from fair to substantial agreement) for primary and secondary enrichments, using real-time PCR. For detection of mecA gene, the kappa statistic was 0–0.49 (from no agreement beyond that expected by chance to moderate agreement) for primary and secondary enrichment samples. Two pork samples were mecA gene positive by all methods. The real-time PCR assay detected the mecA gene in samples that were negative for S. aureus, but positive for Staphylococcus spp. The PVL gene was not detected in any sample by the conventional culture/PCR method or the real-time PCR assay. Among S. aureus isolated by conventional culture/PCR method, the sequence type ST398, and multi-drug resistant strains were found in animals and raw meat samples. The real-time PCR assay may be recommended as a rapid method for detection of S. aureus and the mecA gene, with further confirmation of methicillin-resistant S. aureus (MRSA) using

  12. Ceftobiprole Efficacy In Vitro against Panton-Valentine Leukocidin Production and In Vivo against Community-Associated Methicillin-Resistant Staphylococcus aureus Osteomyelitis in Rabbits

    PubMed Central

    Saleh-Mghir, Azzam; Dumitrescu, Oana; Dinh, Aurélien; Boutrad, Yassine; Massias, Laurent; Martin, Émilie; Vandenesch, François; Etienne, Jérôme

    2012-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) can cause osteomyelitis with severe sepsis and/or local complications in which a Panton-Valentine leukocidin (PVL) role is suspected. In vitro sub-MIC antibiotic effects on growth and PVL production by 11 PVL+ MRSA strains, including the major CA-MRSA clones (USA300, including the LAC strain; USA400; and USA1000), and 11 PVL+ methicillin-susceptible S. aureus (MSSA) strains were tested in microplate culture. Time-kill analyses with ceftobiprole at its MIC were also run with LAC. Efficacies of ceftobiprole (40 mg/kg of body weight subcutaneously [s.c.] four times a day [q.i.d.]) or vancomycin (60 mg/kg intramuscularly [i.m.] twice a day [b.i.d.]) alone or combined with rifampin (10 mg/kg b.i.d.) against rabbit CA-MRSA osteomyelitis, induced by tibial injection of 3.4 × 107 CFU of LAC, were compared. Treatment, started 14 days postinoculation, lasted 14 days. In vitro, 6/11 strains cultured with sub-MICs of ceftobiprole produced 1.6- to 4.8-fold more PVL than did the controls, with no link to specific clones. Rifampin decreased PVL production by all tested strains. In time-kill analyses at the LAC MIC (0.75 mg/liter), PVL production rose transiently at 6 and 8 h and then declined 2-fold at 16 h, concomitant with a 2-log10-CFU-count decrease. In vivo, the mean log10 CFU/g of bone for ceftobiprole (1.44 ± 0.40) was significantly lower than that for vancomycin (2.37 ± 1.22) (P = 0.034), with 7/10 versus 5/11 bones sterilized, respectively. Combination with rifampin enhanced ceftobiprole (1.16 ± 0.04 CFU/g of bone [P = 0.056], 11/11 sterile bones) and vancomycin (1.23 ± 0.06 CFU/g [P = 0.011], 11/11 sterile bones) efficacies. Ceftobiprole bactericidal activity and the rifampin anti-PVL effect could play a role in these findings, which should be of interest for treating CA-MRSA osteomyelitis. PMID:23027197

  13. StaphPlex System for Rapid and Simultaneous Identification of Antibiotic Resistance Determinants and Panton-Valentine Leukocidin Detection of Staphylococci from Positive Blood Cultures▿

    PubMed Central

    Tang, Yi-Wei; Kilic, Abdullah; Yang, Qunying; McAllister, Sigrid K.; Li, Haijing; Miller, Rebecca S.; McCormac, Melinda; Tracy, Karen D.; Stratton, Charles W.; Han, Jian; Limbago, Brandi

    2007-01-01

    Phenotypic methods take several days for identification and antimicrobial susceptibility testing of staphylococcal isolates after gram-positive cocci in clusters (GPCC) are observed in positive blood cultures. We developed and validated a StaphPlex system that amplifies and detects 18 gene targets simultaneously in 1 reaction for species-level identification of staphylococci, detection of genes encoding Panton-Valentine leukocidin (PVL), and antimicrobial resistance determinants of staphylococci. The StaphPlex system was compared to phenotypic methods for organism identification and antimicrobial resistance detection for positive blood culture specimens in which GPCC were observed. Among a total of 360 GPCC specimens, 273 (75.8%), 37 (10.3%), 37 (10.3%), 1 (0.3%), 3 (0.8%), and 9 (2.5%) were identified by StaphPlex as coagulase-negative Staphylococcus (CoNS), methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus (MSSA), or mixed infections of CoNS and MRSA, CoNS and MSSA, or nonstaphylococci, respectively, with an overall accuracy of 91.7%. The 277 CoNS-containing specimens were further identified to the species level as containing 203 (73.3%) Staphylococcus epidermidis isolates, 10 (3.6%) Staphylococcus haemolyticus isolates, 27 (9.7%) Staphylococcus hominis isolates, 1 (0.4%) Staphylococcus lugdunensis isolate, and 36 (13.0%) other CoNS isolates, with an overall accuracy of 80.1% compared to an API STAPH test and CDC reference identification. Numerous very major errors were noticed when detection of aacA, ermA, ermC, tetM, and tetK was used to predict in vitro antimicrobial resistance, but relatively few major errors were observed when the absence of these genes was used to predict susceptibility. The StaphPlex system demonstrated 100% sensitivity and specificity, ranging from 95.5% to 100.0% when used for staphylococcal cassette chromosome mec typing and PVL detection. StaphPlex provides simultaneous staphylococcal identification

  14. Panton-Valentine leukocidin and some exotoxins of Staphylococcus aureus and antimicrobial susceptibility profiles of staphylococci isolated from milks of small ruminants.

    PubMed

    Ünal, Nilgün; Askar, Şinasi; Macun, Hasan Ceyhun; Sakarya, Fatma; Altun, Belgin; Yıldırım, Murat

    2012-03-01

    The aims of this study were to determine the existence of pvl gene, some toxin genes, and mecA gene in Staphylococcus aureus strains isolated from sheep milk and to examine antimicrobial resistance profiles in staphylococci from sheep and goats' milk. The milk samples were collected from 13 different small ruminant farms in Kirikkale province from February to August 2009. A total of 1,604 half-udder milk samples from 857 ewes and 66 half-udder milk samples from 33 goats were collected. Staphylococcus spp. were isolated and identified from the samples. Toxin genes and mecA gene among S. aureus strains were determined by PCR. Antimicrobial susceptibility of staphylococci was examined by the disk diffusion method on Mueller-Hinton agar, and interpreted according to the Clinical Laboratory Standards Institute (CLSI) guidelines. The prevalence of subclinical intramammary infection in both ewes and goats was 5.2%. The most prevalent subclinical mastitis agents were coagulase-negative staphylococci and S. aureus with prevalences 2.8% (n:46) and 1.3% (n = 21), respectively. The prevalence of resistances in isolated Staphylococcus spp. to penicilin G, tetracycline, erythromycin, gentamicin, and enrofloxacin were found as 26.9% (18), 7.5% (5), 6.0% (4), 3.0% (2), and 1.5% (1), respectively. Only 3 of the 21 S. aureus ewe isolates (13.4%) were shown to harbor enterotoxin genes being either seh, sej or sec. However, fourteen (66.6%) of the 21 S. aureus isolates had pvl gene while none of the isolates harbored mecA gene. In conclusion, Staphylococci were shown to be the most prevalent bacteria isolated from subclinical mastitis of ewes and goats and these isolates were susceptible to most of the antibiotics. In addition, S. aureus strains isolated from ewes were harboring few staphylococcal enterotoxin genes. However, Panton-Valentine leukocidin produced by S. aureus could be an important virulence factor and contribute to subclinical mastitis pathogenicity. PMID:21800213

  15. Jim Dine-Inspired Valentines

    ERIC Educational Resources Information Center

    Barlett, April

    2011-01-01

    Jim Dine was born in 1935 in Cincinnati. He earned a BFA from Ohio University in 1957 and then moved to New York in 1959, where he fell in with a group of artists that included Claes Oldenburg. Dine is best known as a Pop innovator, whose paintings, sculptures, and prints were layered with everyday objects, including ties, tools, and even a…

  16. Valentines Day X2 Flare

    NASA Video Gallery

    Active region 1158 let loose with an X2.2 flare at 0153 UT or 8:50 pm ET on February 15, 2011, the largest flare since Dec. 2006 and the biggest flare so far in Solar Cycle 24. This video was taken...

  17. [Investigation of the presence of mecC and Panton-Valentine leukocidin genes in Staphylococcus aureus strains isolated from clinical specimens during seven years period].

    PubMed

    Kılıç, Abdullah; Doğan, Eyüp; Kaya, Sinem; Baysallar, Mehmet

    2015-10-01

    Detection and identification of methicillin-resistant Staphylococcus aureus (MRSA) in clinical microbiology laboratories are important for the selection of appropriate treatment and obtaining epidemiological data. mecC gene, is a mecA homologue, showing almost 69% DNA similarity with the mecA gene and the encoded protein by this gene shows almost 63% similarity with the PBP2a/2' protein. Several studies indicated that mecC positive MRSA strains can be transmitted from the livestock to humans by cross contamination. Panton-Valentine leukocidin (PVL), a potent cytotoxin of S.aureus is also considered as an important virulence factor. The aim of this study was to determine the existence and prevalence of mecC and pvl genes among S.aureus strains isolated from clinical specimens. A total of 1700 S.aureus isolates including 1177 methicillin-susceptible S.aureus (MSSA) and 523 MRSA, isolated in our hospital between January 2007 to December 2014, were included in the study. The isolates were identified by both conventional methods and BD Phoenix automated system (BD Diagnostic Instrument Systems, USA). Antibiotic susceptibility testing was performed by Kirby-Bauer disk diffusion method with oxacillin (1 μg) and cefoxitin (30 μg) according to the CLSI standards. The presence of mecA gene was investigated by the use of real-time PCR, and the presence of pvl and mecC genes were detected by conventional PCR method. Among the patients, 44.6% (759/1700) were outpatients, 65.8% (1119/1700) were male and the mean age of of patients was 39.7 years. Of 1700 isolates evaluated in this study, 523 (30.7%) were positive for mecA gene, however all of them were negative for mecC gene. A total of 32 (1.8%) isolates were positive for pvl gene including 23 (1.9%) out of 1177 MSSA and nine (1.7%) out of 523 MRSA strains. Eighteen (56.2%) of the PVL-positive S.aureus strains were isolated from skin and soft tissue infections. The frequency of PVL detected in this study was similar to the

  18. Detection of ST772 Panton-Valentine leukocidin-positive methicillin-resistant Staphylococcus aureus (Bengal Bay clone) and ST22 S. aureus isolates with a genetic variant of elastin binding protein in Nepal

    PubMed Central

    Pokhrel, R.H.; Aung, M.S.; Thapa, B.; Chaudhary, R.; Mishra, S.K.; Kawaguchiya, M.; Urushibara, N.; Kobayashi, N.

    2016-01-01

    Genetic characteristics were analysed for recent clinical isolates of methicillin-resistant and -susceptible Staphylococcus aureus (MRSA and MSSA respectively) in Kathmandu, Nepal. MRSA isolates harbouring Panton-Valentine leukocidin (PVL) genes were classified into ST1, ST22 and ST88 with SCCmec-IV and ST772 with SCCmec-V (Bengal Bay clone), while PVL-positive MSSA into ST22, ST30 and ST772. ST22 isolates (PVL-positive MRSA and MSSA, PVL-negative MRSA) possessed a variant of elastin binding protein gene (ebpS) with an internal deletion of 180 bp, which was similar to that reported for ST121 S. aureus previously outside Nepal. Phylogenetic analysis indicated that the ebpS variant in ST22 might have occurred independently of ST121 strains. This is the first report of ST772 PVL-positive MRSA in Nepal and detection of the deletion variant of ebpS in ST22 S. aureus. PMID:27014464

  19. Emergence of Panton-Valentine leukocidin-positive ST59 methicillin-susceptible Staphylococcus aureus with high cytolytic peptide expression in association with community-acquired pediatric osteomyelitis complicated by pulmonary embolism.

    PubMed

    Sawanobori, Emi; Hung, Wei-Chun; Takano, Tomomi; Hachuda, Koji; Horiuchi, Tadahiro; Higuchi, Wataru; Hung, Wei-Wen; Iwao, Yasuhisa; Nishiyama, Akihito; Reva, Ivan; Reva, Galina; Teng, Lee-Jene; Yamamoto, Tatsuo

    2015-10-01

    A 15-year-old boy, who had had a furuncle on his femur, developed femoral pyomyositis and osteomyelitis complicated by septic pulmonary embolism. Panton-Valentine leukocidin-positive (PVL(+)) ST59 methicillin-susceptible Staphylococcus aureus (MSSA) was isolated from pus and blood. Chemotherapy was started with cefazolin, followed by combination therapy with meropenem/vancomycin with surgery. The MSSA (strain KS1) was positive for increased levels of cytolytic peptide (psmα and hld) and staphylococcal enterotoxin B (SEB), and manifested IS1216V-mediated multidrug resistance (to erythromycin, clindamycin, kanamycin, streptomycin, and chloramphenicol), similar to a genome-analyzed reference strain (PM1) of ST59/SCCmecV(5C2&5) community-associated methicillin-resistant S. aureus (Taiwan CA-MRSA), but unlike another reference strain (M013) of Taiwan CA-MRSA in terms of resistance. The data suggest that CA-MSSA KS1, characterized by PVL, increased levels of cytolytic peptide, SEB, and multidrug resistance, is a possible ancestral strain of Taiwan CA-MRSA and causes the unique association of osteomyelitis and septic pulmonary embolism, requiring complicated management. PMID:25070278

  20. Molecular characteristics and in vitro susceptibility to antimicrobial agents, including the des-fluoro(6) quinolone DX-619, of Panton-Valentine leucocidin-positive methicillin-resistant Staphylococcus aureus isolates from the community and hospitals.

    PubMed

    Yamamoto, Tatsuo; Dohmae, Soshi; Saito, Kohei; Otsuka, Taketo; Takano, Tomomi; Chiba, Megumi; Fujikawa, Katsuko; Tanaka, Mayumi

    2006-12-01

    Highly virulent, community-acquired methicillin-resistant Staphylococcus aureus (MRSA) strains with Panton-Valentine leucocidin (PVL) genes have been found increasingly worldwide. Among a total of 2,101 MRSA strains isolated from patients in hospitals in Japan, two were positive for PVL genes. One strain was identified as a community-acquired MRSA strain with genotype sequence type 30 (ST30) and spa (staphylococcal protein A gene) type 19 from Japan and was resistant only to beta-lactam antimicrobial agents. The other strain was closely related to PVL+ multidrug-resistant, hospital-acquired MRSA strains (ST30, spa type 43) derived from nosocomial outbreaks in the 1980s to 1990s in Japan but with a divergent sequence type, ST765 (a single-locus variant of ST30). Twenty-two PVL+ MRSA strains, including those from Japan and those from other countries with various sequence types (ST1, ST8, ST30, ST59, and ST80) and genotypes, were examined for susceptibility to 31 antimicrobial agents. Among the agents, DX-619, a des-fluoro(6) quinolone, showed the greatest activity, followed by rifampin and sitafloxacin, a fluoroquinolone. The data suggest that DX-619 exhibits a superior activity against PVL+ MRSA strains with various virulence genetic traits from the community as well as from hospitals. PMID:17043124

  1. Emergence of Panton-Valentine leucocidin-positive ST8-methicillin-resistant Staphylococcus aureus (USA300 clone) in Korea causing healthcare-associated and hospital-acquired bacteraemia.

    PubMed

    Jung, J; Song, E H; Park, S Y; Lee, S-R; Park, S-J; Sung, H; Kim, M-N; Kim, S-H; Lee, S-O; Choi, S-H; Woo, J H; Kim, Y S; Chong, Y P

    2016-08-01

    Panton-Valentine leucocidin (PVL)-positive sequence type (ST)8-MRSA-SCCmec IVa (USA300) is the epidemic strain of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in North America. USA300 is extremely rare in South Korea, and PVL-negative ST72 SCCmec type IVc is the predominant CA-MRSA clone. In a multicentre, prospective cohort study of S. aureus bacteraemia, we identified PVL-positive ST8-MRSA isolates by performing multilocus sequence typing and PCR for PVL. We analyzed the clinical characteristics of patients with PVL-positive ST8-MRSA bacteraemia, and performed SCCmec, spa, and agr typing, PCR for arginine catabolic mobile element (ACME), virulence gene profiling, and pulsed-field gel electrophoresis (PFGE). Among a total of 818 MRSA isolates, we identified ten isolates of PVL-positive ST8-MRSA (USA300) (3 from Hospital D, 4 from Hospital G, and 3 from Hospital A), all of which involved exclusively healthcare-associated (5 isolates) and hospital-acquired bacteraemia (5 isolates). This strain accounted for 8~10 % of the hospital-acquired MRSA bacteraemia in Hospitals D and G. Bacteraemia of unknown origin was the most common type of infection followed by pneumonia. All the isolates were SCCmec type IVa, spa type t008, and agr group I. Eight of the isolates harboured ACME. In a PFGE analysis, four isolates were identical to the USA300 control strain, five differed by a single band, and the remaining one differed by two bands. All the isolates were pulsed-field type USA300. This is the first report of healthcare-associated and hospital-acquired bacteraemia caused by USA300 in South Korea. USA300 seems to be an emerging hospital clone in this country. PMID:27209287

  2. Genotyping of methicillin-resistant Staphylococcus aureus in the Sultan Qaboos University Hospital, Oman reveals the dominance of Panton–Valentine leucocidin-negative ST6-IV/t304 clone

    PubMed Central

    Udo, E E; Al-Lawati, B A-H; Al-Muharmi, Z; Thukral, S S

    2014-01-01

    The objective of this study was to determine the prevalence and distribution of methicillin-resistant Staphylococcus aureus (MRSA) genotypes circulating at a tertiary hospital in the Sultanate of Oman. A total of 79 MRSA isolates were obtained from different clinical samples and investigated using antibiogram, pulsed-field gel electrophoresis (PFGE), staphylococcal chromosome cassette mec (SCCmec), Spa typing and multilocus sequence typing (MLST). The isolates were susceptible to linezolid, vancomycin, teicoplanin, tigecycline and mupirocin but were resistant to tetracycline (30.4%), erythromycin (26.6%), clindamycin (24.1%), trimethoprim (19.0%), ciprofloxacin (17.7%), fusidic acid (15.2%) and gentamicin (12.7%). Molecular typing revealed 19 PFGE patterns, 26 Spa types and 21 sequence types. SCCmec-IV (86.0%) was the dominant SCCmec type, followed by SCCmec-V (10.1%). SCCmec-III (2.5%) and SCCmec-II (1.3%) were less common. ST6-IV/t304 (n = 30) and ST1295-IV/t690 (n = 12) were the dominant genotypes followed by ST772-V/t657 (n = 5), ST30-IV/t019/t021 (n = 5), ST22-IV/t852 (n = 4), ST80-IV/t044 (n = 3) and 18 single genotypes that were isolated sporadically. On the basis of SCCmec typing and MLST, 91.2% of the isolates were classified as community-associated MRSA and 8.8% of the isolates (consisting of four ST22-IV/t852, one ST239-III/t632, one ST5-III/t311 and one ST5-II/t003) were classified as healthcare-associated MRSA. The study has revealed the dominance of a Panton–Valentine leucocidin-negative ST6-IV/t304 clone and provided insights into the distribution of antibiotic resistance in MRSA at the tertiary hospital in Oman. It also highlights the importance of surveillance in detecting the emergence of new MRSA clones in a healthcare facility. PMID:25356354

  3. Presence of the Panton-Valentine Leukocidin Genes in Methicillin-Resistant Staphylococcus aureus Is Associated with Severity and Clinical Outcome of Hospital-Acquired Pneumonia in a Single Center Study in China

    PubMed Central

    Zhang, Chuanling; Guo, Liang; Chu, Xu; Shen, Limeng; Guo, Yuanyu; Dong, Huali; Mao, Jianfeng; van der Veen, Stijn

    2016-01-01

    The Panton-Valentine leukocidin (PVL) genes of methicillin-resistant Staphylococcus aureus (MRSA) have previously been associated with severe infections. Here, the impact of the PVL genes on severity of disease and clinical outcome of patients with hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP) due to MRSA was investigated in a single center observational study in a hospital in China. HAP due to MRSA was diagnosed in 100 patients and 13 of the patients were PVL positive, while VAP was diagnosed in 5 patients and 2 were PVL positive. The PVL positive patient group showed a significantly higher Acute Physiology and Chronic Health Evaluation (APACHE) II score (14.3 ±7.8 vs. 10.1 ±4.7, P = 0.005) and significantly more patients with CRP levels >80 mg/L (8/15 vs. 12/90, P = 0.006) or WBC counts >15x109/L (7/15 vs. 12/90, P = 0.006), indicating that the severity of disease is affected by the presence of the PVL genes. The outcome of the study was defined by 30-day mortality. Four (27%) of the PVL positive patients and four (4%) of the PVL negative patients died within 30 days (P = 0.01, Fisher exact test). Kaplan-Meier survival curves were generated for the PVL positive and PVL negative patient groups, which differed significantly (P = 0.003). Among the patients that died, the mean interval between diagnosis and death was shorter for the PVL positive patients (9.3 ±5.6 vs. 40.8 ±6.6 days, P = 0.013). Further analysis within the HAP and VAP patient groups showed that the presence of PVL in MRSA impacted the severity of disease and clinical outcome of HAP, but for VAP the number of patients included in the study was too low. In conclusion, in this single center study in a Chinese hospital the presence of the PVL genes in MRSA impacted the severity of disease and clinical outcome in patients with HAP due to MRSA. PMID:27249225

  4. Presence of the Panton-Valentine Leukocidin Genes in Methicillin-Resistant Staphylococcus aureus Is Associated with Severity and Clinical Outcome of Hospital-Acquired Pneumonia in a Single Center Study in China.

    PubMed

    Zhang, Chuanling; Guo, Liang; Chu, Xu; Shen, Limeng; Guo, Yuanyu; Dong, Huali; Mao, Jianfeng; van der Veen, Stijn

    2016-01-01

    The Panton-Valentine leukocidin (PVL) genes of methicillin-resistant Staphylococcus aureus (MRSA) have previously been associated with severe infections. Here, the impact of the PVL genes on severity of disease and clinical outcome of patients with hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP) due to MRSA was investigated in a single center observational study in a hospital in China. HAP due to MRSA was diagnosed in 100 patients and 13 of the patients were PVL positive, while VAP was diagnosed in 5 patients and 2 were PVL positive. The PVL positive patient group showed a significantly higher Acute Physiology and Chronic Health Evaluation (APACHE) II score (14.3 ±7.8 vs. 10.1 ±4.7, P = 0.005) and significantly more patients with CRP levels >80 mg/L (8/15 vs. 12/90, P = 0.006) or WBC counts >15x109/L (7/15 vs. 12/90, P = 0.006), indicating that the severity of disease is affected by the presence of the PVL genes. The outcome of the study was defined by 30-day mortality. Four (27%) of the PVL positive patients and four (4%) of the PVL negative patients died within 30 days (P = 0.01, Fisher exact test). Kaplan-Meier survival curves were generated for the PVL positive and PVL negative patient groups, which differed significantly (P = 0.003). Among the patients that died, the mean interval between diagnosis and death was shorter for the PVL positive patients (9.3 ±5.6 vs. 40.8 ±6.6 days, P = 0.013). Further analysis within the HAP and VAP patient groups showed that the presence of PVL in MRSA impacted the severity of disease and clinical outcome of HAP, but for VAP the number of patients included in the study was too low. In conclusion, in this single center study in a Chinese hospital the presence of the PVL genes in MRSA impacted the severity of disease and clinical outcome in patients with HAP due to MRSA. PMID:27249225

  5. Panton-Valentine Leukocidin-Positive Staphylococcus aureus in Ireland from 2002 to 2011: 21 Clones, Frequent Importation of Clones, Temporal Shifts of Predominant Methicillin-Resistant S. aureus Clones, and Increasing Multiresistance

    PubMed Central

    Shore, Anna C.; Tecklenborg, Sarah C.; Brennan, Gráinne I.; Ehricht, Ralf; Monecke, Stefan

    2014-01-01

    There has been a worldwide increase in community-associated (CA) methicillin-resistant Staphylococcus aureus (MRSA) infections. CA-MRSA isolates commonly produce the Panton-Valentine leukocidin toxin encoded by the pvl genes lukF-PV and lukS-PV. This study investigated the clinical and molecular epidemiologies of pvl-positive MRSA and methicillin-susceptible S. aureus (MSSA) isolates identified by the Irish National MRSA Reference Laboratory (NMRSARL) between 2002 and 2011. All pvl-positive MRSA (n = 190) and MSSA (n = 39) isolates underwent antibiogram-resistogram typing, spa typing, and DNA microarray profiling for multilocus sequence type, clonal complex (CC) and/or sequence type (ST), staphylococcal cassette chromosome mec type assignment, and virulence and resistance gene detection. Where available, patient demographics and clinical data were analyzed. The prevalence of pvl-positive MRSA increased from 0.2% to 8.8%, and that of pvl-positive MSSA decreased from 20% to 2.5% during the study period. The pvl-positive MRSA and MSSA isolates belonged to 16 and 5 genotypes, respectively, with CC/ST8-MRSA-IV, CC/ST30-MRSA-IV, CC/ST80-MRSA-IV, CC1/ST772-MRSA-V, CC30-MSSA, CC22-MSSA, and CC121-MSSA predominating. Temporal shifts in the predominant pvl-positive MRSA genotypes and a 6-fold increase in multiresistant pvl-positive MRSA genotypes occurred during the study period. An analysis of patient data indicated that pvl-positive S. aureus strains, especially MRSA strains, had been imported into Ireland several times. Two hospital and six family clusters of pvl-positive MRSA were identified, and 70% of the patient isolates for which information was available were from patients in the community. This study highlights the increased burden and changing molecular epidemiology of pvl-positive S. aureus in Ireland over the last decade and the contribution of international travel to the influx of genetically diverse pvl-positive S. aureus isolates into Ireland. PMID:24371244

  6. 2011 Valentines Day X-Class Flare

    NASA Video Gallery

    The video clip of the large X2 flare seen by Solar Dynamics Observatory (SDO) in extreme ultraviolet light on February 15, 2011, has been enlarged and superimposed on a video of SOHO's C2 coronagra...

  7. Valentin Peschansky and the puzzles of magnetotransport

    NASA Astrophysics Data System (ADS)

    Pudalov, V. M.

    2011-10-01

    Since the 1950's, the Kharkov school of theoretical physics has been a world leader in the theory of metals. In particular, the research by V. G. Peschansky for many years has focused on the relationship between the magnetic field dependence of components of the resistivity and the electron energy spectrum. Peschansky developed an elegant theory of magnetoresistance that took surface scattering of electrons into account. The physics of bulk 3D metals was almost exhausted by the end of 1970's and Peschansky extended his research to low-dimensional electron systems. Throughout his scientific life, V. G. Peschansky has advocated the idea that magnetoresistance is a powerful tool for exploring the rich physics of electron systems. The many experimental and theoretical studies of magnetoresistance behavior in various systems, from simple to the most complex, have, by now, confirmed the fruitfulness of this idea.

  8. Start II, red ink, and Boris Yeltsin

    SciTech Connect

    Arbatov, A.

    1993-04-01

    Apart from the vulnerability implied by the START II treaty, it will bear the burden of the general political opposition to the Yeltsin administration. START II will be seen as part of an overall Yeltsin-Andrei Kozyrev foreign policy that is under fire for selling out Russian national interests in Yugoslavia, the Persian Gulf, and elsewhere. This article discusses public opinion concerning START II, the cost of its implementation, and the general purpose of the treaty.

  9. Emergence of Hospital- and Community-Associated Panton-Valentine Leukocidin-Positive Methicillin-Resistant Staphylococcus aureus Genotype ST772-MRSA-V in Ireland and Detailed Investigation of an ST772-MRSA-V Cluster in a Neonatal Intensive Care Unit

    PubMed Central

    Shore, Anna C.; Corcoran, Suzanne; Tecklenborg, Sarah; Coleman, David C.; O'Connell, Brian

    2012-01-01

    Sequence type 22 (ST22) methicillin-resistant Staphylococcus aureus (MRSA) harboring staphylococcal cassette chromosome mec (SCCmec) IV (ST22-MRSA-IV) has predominated in Irish hospitals since the late 1990s. Six distinct clones of community-associated MRSA (CA-MRSA) have also been identified in Ireland. A new strain of CA-MRSA, ST772-MRSA-V, has recently emerged and become widespread in India and has spread into hospitals. In the present study, highly similar MRSA isolates were recovered from seven colonized neonates in a neonatal intensive care unit (NICU) in a maternity hospital in Ireland during 2010 and 2011, two colonized NICU staff, one of their colonized children, and a NICU environmental site. The isolates exhibited multiantibiotic resistance, spa type t657, and were assigned to ST772-MRSA-V by DNA microarray profiling. All isolates encoded resistance to macrolides [msr(A) and mpb(BM)] and aminoglycosides (aacA-aphD and aphA3) and harbored the Panton-Valentine leukocidin toxin genes (lukF-PV and lukS-PV), enterotoxin genes (sea, sec, sel, and egc), and one of the immune evasion complex genes (scn). One of the NICU staff colonized by ST772-MRSA-V was identified as the probable index case, based on recent travel to India. Seven additional hospital and CA-ST772-MRSA-V isolates recovered from skin and soft tissue infections in Ireland between 2009 and 2011 exhibiting highly similar phenotypic and genotypic characteristics to the NICU isolates were also identified. The clinical details of four of these patients revealed connections with India through ethnic background or travel. Our study indicates that hospital-acquired and CA-ST772-MRSA-V is currently emerging in Ireland and may have been imported from India on several occasions. PMID:22189119

  10. Romance of a Mathematician: Celebrating St Valentine's Day in a Mathematics Class

    ERIC Educational Resources Information Center

    Hekimoglu, Serkan

    2005-01-01

    Mathematics should not be studied simply because it is useful; mathematics should be also studied because it nurtures both the mind and soul with its beauty. By completing the four activities described in this paper, students will appreciate mathematical ideas both rationally and emotionally. Since students' appreciation of mathematical ideas…

  11. Staphylococcus aureus Panton-Valentine leukocidin induces an inflammatory response in human phagocytes via the NLRP3 inflammasome

    PubMed Central

    Holzinger, Dirk; Gieldon, Laura; Mysore, Vijayashree; Nippe, Nadine; Taxman, Debra J.; Duncan, Joseph A.; Broglie, Peter M.; Marketon, Kristina; Austermann, Judith; Vogl, Thomas; Foell, Dirk; Niemann, Silke; Peters, Georg; Roth, Johannes; Löffler, Bettina

    2012-01-01

    The Staphylococcus aureus pore-forming toxin PVL is most likely causative for life-threatening necrotizing infections, which are characterized by massive tissue inflammation and necrosis. Whereas the cytotoxic action of PVL on human neutrophils is already well established, the PVL effects on other sensitive cell types, such as monocytes and macrophages, are less clear. In this study, we used different types of human leukocytes (neutrophils, monocytes, macrophages, lymphocytes) to investigate cell-specific binding of PVL subunits and subsequent proinflammatory and cytotoxic effects. In all PVL-sensitive cells, we identified the binding of the subunit LukS-PV as the critical factor for PVL-induced cytotoxicity, which was followed by binding of LukF-PV. LukS-PV binds to monocytes, macrophages, and neutrophils but not to lymphocytes. Additionally, we showed that PVL binding to monocytes and macrophages leads to release of caspase-1-dependent proinflammatory cytokines IL-1β and IL-18. PVL activates the NLRP3 inflammasome, a signaling complex of myeloid cells that is involved in caspase-1-dependent IL-1β processing in response to pathogens and endogenous danger signals. Specific inhibition of this pathway at several steps significantly reduced inflammasome activation and subsequent pyronecrosis. Furthermore, we found that PAMPs and DAMPs derived from dying neutrophils can dramatically enhance this response by up-regulating pro-IL-1β in monocytes/macrophages. This study analyzes a specific host signaling pathway that mediates PVL-induced inflammation and cytotoxicity, which has high relevance for CA-MRSA-associated and PVL-mediated pathogenic processes, such as necrotizing infections. PMID:22892107

  12. Share the Love: Why Not Celebrate Valentine's Day by Encouraging Kids to Give Back to the Community?

    ERIC Educational Resources Information Center

    Jackson, Nancy Mann

    2011-01-01

    February is a natural time to teach students that love involves more than hearts and candy--it also means giving of oneself. According to Terri Kennamer, a third-grade teacher at West Elementary School in Vestavia Hills, Alabama, it is the responsibility of educators to help students recognize that they are citizens of the world. Children have…

  13. Staphylococcus aureus Panton-Valentine leukocidin induces an inflammatory response in human phagocytes via the NLRP3 inflammasome.

    PubMed

    Holzinger, Dirk; Gieldon, Laura; Mysore, Vijayashree; Nippe, Nadine; Taxman, Debra J; Duncan, Joseph A; Broglie, Peter M; Marketon, Kristina; Austermann, Judith; Vogl, Thomas; Foell, Dirk; Niemann, Silke; Peters, Georg; Roth, Johannes; Löffler, Bettina

    2012-11-01

    The Staphylococcus aureus pore-forming toxin PVL is most likely causative for life-threatening necrotizing infections, which are characterized by massive tissue inflammation and necrosis. Whereas the cytotoxic action of PVL on human neutrophils is already well established, the PVL effects on other sensitive cell types, such as monocytes and macrophages, are less clear. In this study, we used different types of human leukocytes (neutrophils, monocytes, macrophages, lymphocytes) to investigate cell-specific binding of PVL subunits and subsequent proinflammatory and cytotoxic effects. In all PVL-sensitive cells, we identified the binding of the subunit LukS-PV as the critical factor for PVL-induced cytotoxicity, which was followed by binding of LukF-PV. LukS-PV binds to monocytes, macrophages, and neutrophils but not to lymphocytes. Additionally, we showed that PVL binding to monocytes and macrophages leads to release of caspase-1-dependent proinflammatory cytokines IL-1β and IL-18. PVL activates the NLRP3 inflammasome, a signaling complex of myeloid cells that is involved in caspase-1-dependent IL-1β processing in response to pathogens and endogenous danger signals. Specific inhibition of this pathway at several steps significantly reduced inflammasome activation and subsequent pyronecrosis. Furthermore, we found that PAMPs and DAMPs derived from dying neutrophils can dramatically enhance this response by up-regulating pro-IL-1β in monocytes/macrophages. This study analyzes a specific host signaling pathway that mediates PVL-induced inflammation and cytotoxicity, which has high relevance for CA-MRSA-associated and PVL-mediated pathogenic processes, such as necrotizing infections. PMID:22892107

  14. The relation between soil sulfate concentration and proanthocyanidin content of Selliguea feei Bory from around Ratu crater, Mount Tangkuban Perahu

    NASA Astrophysics Data System (ADS)

    Novianti, Vivi; Choesin, Devi N.

    2014-03-01

    Proanthocyanidin is a chemical compound with a basic flavan-3-ol structure formed from flavonoid secondary metabolism in plants, with potential for human use because of its anti-hypertension, analgesic, anti-inflammatory and antioxidant activities. Considering the fact that S. feei contains proanthocynidin and grows abundantly around Ratu Crater, Mount Tangkuban Perahu, which actively emits S02 gas, this study aimed to see the relation between soil sulfate concentration and proanthocyanidin content in leaves and rhizomes of S. feei. Field sampling was conducted in 1 m2 plots at elevations of 1400, 1600 m above sea level (100 m distance from sulfur source), 1700, 1800 and 1900 m a.s.l. (75 m from sulfur source). Measurements included soil sulfate concentration, proanthocyanidin content of rhizomes and leaves, and environmental factors. An experiment was conducted by planting S. feei from the field into polybags which were then given treatments of sterile plant media with varying sulfate concentrations (0 ppm, 100 ppm, 250 ppm, 400 ppm, 600 ppm, and 800 ppm). Proanthocyanidin content of S. feei leaves and rhizomes were measured on the third, sixth and ninth week. Soil sulfate concentrations were found to be very high (428.22 - 992.91 ppm) with values increasing according to altitude. Proanthocyanidin content in rhizomes were higher than in leaves, in both field and experimental data. Soil sulfate concentrations correlated positively and significantly with proanthocyanidin content in rhizomes of S. feei. As in the field, experimental results indicated no correlation or relation between soil sulfate concentration and proanthocyanidin content in leaves. Besides soil sulfate concentration, environmental factors have a role in incresing peoanthocyanidin content of S.feei. Proanthocyanidin content of S.feei rhizomes could be classified as being very high, thus having potential to be developed as raw material in medicine and food industries.

  15. The role of authigenic sulfides in immobilization of potentially toxic metals in the Bagno Bory wetland, southern Poland.

    PubMed

    Smieja-Król, Beata; Janeczek, Janusz; Bauerek, Arkadiusz; Thorseth, Ingunn H

    2015-10-01

    The supply of Cd, Cu, Fe, Pb, Zn, and Tl into a wetland in the industrial area of Upper Silesia, southern Poland via atmospheric precipitation and dust deposition has been counterbalanced by the biogenic metal sulfide crystallization in microsites of the thin (<30 cm) peat layer, despite the overall oxidative conditions in the wetland. Disequilibrium of the redox reactions in the peat pore water (pH 5.4-6.2) caused by sulfate-reducing microorganisms has resulted in the localized decrease in Eh and subsequent precipitation of micron- and submicron-sized framboidal pyrite, spheroidal ZnS and (Zn,Cd)S, and galena as revealed by high-resolution scanning electron microscopy (SEM)/energy dispersive spectrometer (EDS). Saturation index for each sulfide is at a maximum within the calculated Eh range of -80 and -146 mV. Lead was also immobilized in galena deposited in fungal filaments, possibly at a higher Eh. Thallium (up to 3 mg kg(-1)) in the peat strongly correlates with Zn, whereas Cu (up to 55 mg kg(-1)) co-precipitated with Pb. The metal sulfides occur within microbial exudates, which protect them from oxidation and mechanical displacement. Vertical distribution of toxic metals in the peat layer reflects differences in pollution loads from atmospheric deposition, which has been much reduced recently. PMID:26006073

  16. Outbreak of Skin Infections Due to Panton-Valentine Leukocidin-Positive Methicillin-Susceptible Staphylococcus aureus in a French Prison in 2010-2011

    PubMed Central

    Bourigault, Céline; Corvec, Stéphane; Brulet, Virginie; Robert, Pierre-Yves; Mounoury, Olivier; Goubin, Chloé; Boutoille, David; Hubert, Bruno; Bes, Michèle; Tristan, Anne; Etienne, Jérôme; Lepelletier, Didier

    2014-01-01

    Background. An outbreak of PVL-positive MSSA skin and soft tissue-infections (SSTIs) was suspected in May 2010 when recurrent SSTI was diagnosed in an inmate of a large prison in Nantes, France. Methods and findings. Retrospective and prospective investigations were performed. Microbiological characterisation was by DNA microarray testing (S. aureus genotyping - Identibac, Alere). We identified 14 inmates meeting our clinical and microbiological case definition for PVL-MSSA SSTI between March 2010 and April 2011. The SSTIs developed in tattooed areas in 4 patients and in areas shaved daily with a mechanical razor in 4 other patients. All case isolates exhibited a similar SmaI pulsed-field gel electrophoresis pattern. Microarray analysis showed that all 14 isolates harboured genes encoding PVL and enterotoxins (A, H, K, and Q) and belonged to clonal complex 1 (CC1). Individual and collective hygiene measures, education delivered to inmates and prison employees, and antibiotic treatment of SSTIs were successful in controlling the outbreak. No new cases were identified after April 2011. Routine screening for PVL-positive MSSA carriage was not feasible. Conclusions. Our data suggest that tattooing and shaving with mechanical razors may constitute risk factors for SSTIs among previously colonised inmates and contribute to the PVL-MSSA outbreak in the prison. Allowing inmates access to professional tattooists and to the hygiene and safety conditions available to people in the community would help to prevent tattoo-related infections. PMID:24619564

  17. Molecular characterization of methicillin-resistant Panton-valentine leukocidin positive staphylococcus aureus clones disseminating in Tunisian hospitals and in the community

    PubMed Central

    2013-01-01

    Background The spread of MRSA strains at hospitals as well as in the community are of great concern worldwide. We characterized the MRSA clones isolated at Tunisian hospitals and in the community by comparing them to those isolated in other countries. Results We characterized 69 MRSA strains isolated from two Tunisian university hospitals between the years 2004-2008. Twenty-two of 28 (79%) community-associated MRSA (CA-MRSA) strains and 21 of 41 (51%) healthcare-associated MRSA (HA-MRSA) strains were PVL-positive. The PVL-positive strains belonged to predicted founder group (FG) 80 in MLST and carried either type IVc SCCmec or nontypeable SCCmec that harbours the class B mec gene complex. In contrast, very diverse clones were identified in PVL-negative strains: three FGs (5, 15, and 22) for HA-MRSA strains and four FGs (5, 15, 45, and 80) for CA-MRSA strains; and these strains carried the SCCmec element of either type I, III, IVc or was nontypeable. The nucleotide sequencing of phi7401PVL lysogenized in a CA-MRSA strain JCSC7401, revealed that the phage was highly homologous to phiSA2mw, with nucleotide identities of more than 95%. Furthermore, all PVL positive strains were found to carry the same PVL phage, since these strains were positive in two PCR studies, identifying gene linkage between lukS and mtp (major tail protein) and the lysogeny region, both of which are in common with phi7401PVL and phiSa2mw. Conclusions Our experiments suggest that FG80 S. aureus strains have changed to be more virulent by acquiring phi7401PVL, and to be resistant to β-lactams by acquiring SCCmec elements. These novel clones might have disseminated in the Tunisian community as well as at the Tunisian hospitals by taking over existing MRSA clones. PMID:23289889

  18. Panton-valentine leukocidin-positive and toxic shock syndrome toxin 1-positive methicillin-resistant Staphylococcus aureus: a French multicenter prospective study in 2008.

    PubMed

    Robert, Jérôme; Tristan, Anne; Cavalié, Laurent; Decousser, Jean-Winoc; Bes, Michèle; Etienne, Jerome; Laurent, Frédéric

    2011-04-01

    The epidemiology of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) differs from country to country. We assess the features of the ST80 European clone, which is the most prevalent PVL-positive CA-MRSA clone in Europe, and the TSST-1 ST5 clone that was recently described in France. In 2008, all MRSA strains susceptible to fluoroquinolones and gentamicin and resistant to fusidic acid that were isolated in 104 French laboratories were characterized using agr alleles, spa typing, and the staphylococcal cassette chromosome mec element and PCR profiling of 21 toxin genes. Three phenotypes were defined: (i) kanamycin resistant, associated with the ST80 clone; (ii) kanamycin and tobramycin resistant, associated with the ST5 clone; and (iii) aminoglycoside susceptible, which was less frequently associated with the ST5 clone. Among the 7,253 MRSA strains isolated, 91 (1.3%) were ST80 CA-MRSA (89 phenotype 1) and 190 (2.6%) were ST5 CA-MRSA (146 phenotype 2, 42 phenotype 3). Compared to the latter, ST80 CA-MRSAs were more likely to be community acquired (80% versus 46%) and found in young patients (median age, 26.0 years versus 49.5 years) with deep cutaneous infections (48% versus 6%). They were less likely to be tetracycline susceptible (22% versus 85%) and to be isolated from respiratory infections (6% versus 27%). The TSST-1 ST5 clone has rapidly emerged in France and has become even more prevalent than the ST80 European clone, whose prevalence has remained stable. The epidemiological and clinical patterns of the two clones differ drastically. Given the low prevalence of both among all staphylococcal infections, no modification of antibiotic recommendations is required yet. PMID:21220529

  19. Outbreak of Skin Infections Due to Panton-Valentine Leukocidin-Positive Methicillin-Susceptible Staphylococcus aureus in a French Prison in 2010-2011.

    PubMed

    Bourigault, Céline; Corvec, Stéphane; Brulet, Virginie; Robert, Pierre-Yves; Mounoury, Olivier; Goubin, Chloé; Boutoille, David; Hubert, Bruno; Bes, Michèle; Tristan, Anne; Etienne, Jérôme; Lepelletier, Didier

    2014-01-01

    Background. An outbreak of PVL-positive MSSA skin and soft tissue-infections (SSTIs) was suspected in May 2010 when recurrent SSTI was diagnosed in an inmate of a large prison in Nantes, France. Methods and findings. Retrospective and prospective investigations were performed. Microbiological characterisation was by DNA microarray testing (S. aureus genotyping - Identibac, Alere). We identified 14 inmates meeting our clinical and microbiological case definition for PVL-MSSA SSTI between March 2010 and April 2011. The SSTIs developed in tattooed areas in 4 patients and in areas shaved daily with a mechanical razor in 4 other patients. All case isolates exhibited a similar SmaI pulsed-field gel electrophoresis pattern. Microarray analysis showed that all 14 isolates harboured genes encoding PVL and enterotoxins (A, H, K, and Q) and belonged to clonal complex 1 (CC1). Individual and collective hygiene measures, education delivered to inmates and prison employees, and antibiotic treatment of SSTIs were successful in controlling the outbreak. No new cases were identified after April 2011. Routine screening for PVL-positive MSSA carriage was not feasible. Conclusions. Our data suggest that tattooing and shaving with mechanical razors may constitute risk factors for SSTIs among previously colonised inmates and contribute to the PVL-MSSA outbreak in the prison. Allowing inmates access to professional tattooists and to the hygiene and safety conditions available to people in the community would help to prevent tattoo-related infections. PMID:24619564

  20. Panton-Valentine Leukocidin-Positive and Toxic Shock Syndrome Toxin 1-Positive Methicillin-Resistant Staphylococcus aureus: a French Multicenter Prospective Study in 2008▿

    PubMed Central

    Robert, Jérôme; Tristan, Anne; Cavalié, Laurent; Decousser, Jean-Winoc; Bes, Michèle; Etienne, Jerome; Laurent, Frédéric

    2011-01-01

    The epidemiology of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) differs from country to country. We assess the features of the ST80 European clone, which is the most prevalent PVL-positive CA-MRSA clone in Europe, and the TSST-1 ST5 clone that was recently described in France. In 2008, all MRSA strains susceptible to fluoroquinolones and gentamicin and resistant to fusidic acid that were isolated in 104 French laboratories were characterized using agr alleles, spa typing, and the staphylococcal cassette chromosome mec element and PCR profiling of 21 toxin genes. Three phenotypes were defined: (i) kanamycin resistant, associated with the ST80 clone; (ii) kanamycin and tobramycin resistant, associated with the ST5 clone; and (iii) aminoglycoside susceptible, which was less frequently associated with the ST5 clone. Among the 7,253 MRSA strains isolated, 91 (1.3%) were ST80 CA-MRSA (89 phenotype 1) and 190 (2.6%) were ST5 CA-MRSA (146 phenotype 2, 42 phenotype 3). Compared to the latter, ST80 CA-MRSAs were more likely to be community acquired (80% versus 46%) and found in young patients (median age, 26.0 years versus 49.5 years) with deep cutaneous infections (48% versus 6%). They were less likely to be tetracycline susceptible (22% versus 85%) and to be isolated from respiratory infections (6% versus 27%). The TSST-1 ST5 clone has rapidly emerged in France and has become even more prevalent than the ST80 European clone, whose prevalence has remained stable. The epidemiological and clinical patterns of the two clones differ drastically. Given the low prevalence of both among all staphylococcal infections, no modification of antibiotic recommendations is required yet. PMID:21220529

  1. Incidence of community-acquired methicillin-resistant Staphylococcus aureus carrying Pantone-Valentine leucocidin gene at a referral hospital in United Arab Emirates.

    PubMed

    Dash, Nihar; Panigrahi, Debadatta; Al Zarouni, Mansour; Yassin, Faten; Al-Shamsi, Moza

    2014-04-01

    Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is an emerging pathogen in hospitalized patients worldwide. The present study was undertaken to identify CA-MRSA in hospitalized patients in a 350-bed tertiary care hospital in Sharjah, UAE over a 2-year period from January 2011 to December 2012. CA-MRSA was defined based on identification within first 48 h of admission in the hospital. Staphylococcal cassette chromosome (SCC) mec typing of the CA-MRSA isolates was carried out by multiplex polymerase chain reaction (PCR). Detection of PVL and mecA genes was done by PCR using the GenoType(®) MRSA test system (Hain Lifescience). Patient's clinical data and antimicrobial susceptibility pattern of the CA-MRSA isolates were also evaluated. Fifty seven of the 187 MRSA isolates were identified as CA-MRSA. All the CA-MRSA strains in our study belonged to SCCmecIV type and were positive for both PVL and mecA genes. The patients with CA-MRSA infections were young (median age, 32 years) and the majority of infections involved the skin and soft tissue (36%). Antimicrobial susceptibility pattern of the CA-MRSA isolates showed a better susceptibility profile to the non-beta-lactam antimicrobials with the exception of ciprofloxacin having 28% resistance. This study evidently strengthens the recent observation of an increase in CA-MRSA emergence among hospitalized patients in the UAE. PMID:23919760

  2. Modeling of Localized Neutral Particle Sources in 3D Edge Plasmas

    SciTech Connect

    Umansky, M V; Rognlien, T D; Fenstermacher, M E; Borchardt, M; Mutzke, A; Riemann, J; Schneider, R; Owen, L W

    2002-05-23

    A new edge plasma code BoRiS [1] has a fully 3D fluid plasma model. We supplement BoRiS with a 3D fluid neutral model including equations for parallel momentum and collisional perpendicular diffusion. This makes BoRiS an integrated plasma-neutral model suitable for a variety of applications. We present modeling results for a localized gas source in the geometry of the NCSX stellarator.

  3. Review of Empirical Research That Utilized the Bell Object Relations Inventory.

    ERIC Educational Resources Information Center

    Hansen, Joseph Wm.

    This literature review examines how the Bell Object Relations Inventory (BORI) (M. Bell and others, 1986) has been used in the literature. General domains of BORI use include interpersonal relatedness, the measurement of religious dimensions, and the diagnosis and prediction of psychopathology. Specific areas are reviewed regarding the…

  4. Basic Operational Robotics Instructional System

    NASA Technical Reports Server (NTRS)

    Todd, Brian Keith; Fischer, James; Falgout, Jane; Schweers, John

    2013-01-01

    The Basic Operational Robotics Instructional System (BORIS) is a six-degree-of-freedom rotational robotic manipulator system simulation used for training of fundamental robotics concepts, with in-line shoulder, offset elbow, and offset wrist. BORIS is used to provide generic robotics training to aerospace professionals including flight crews, flight controllers, and robotics instructors. It uses forward kinematic and inverse kinematic algorithms to simulate joint and end-effector motion, combined with a multibody dynamics model, moving-object contact model, and X-Windows based graphical user interfaces, coordinated in the Trick Simulation modeling environment. The motivation for development of BORIS was the need for a generic system for basic robotics training. Before BORIS, introductory robotics training was done with either the SRMS (Shuttle Remote Manipulator System) or SSRMS (Space Station Remote Manipulator System) simulations. The unique construction of each of these systems required some specialized training that distracted students from the ideas and goals of the basic robotics instruction.

  5. Into the Curriculum. Creative Dramatics: Valentine Lip Sync Book Charades; Language Arts/Social Studies: Found Poetry from Primary Sources; Reading/Language Arts: A Thematic Activity To Herald in the New Year; Science: Asian Elephant Life Cycles; Social Studies: Conservation of Animal Species-Asian Elephants; Social Studies: What Makes a Leader?

    ERIC Educational Resources Information Center

    Shugar, Candace; Robinson, Alice A.

    2003-01-01

    Provides six fully developed library media activities that are designed for use with specific curriculum units in creative dramatics, language arts, social studies, reading, and science. Library media skills, curriculum objectives, grade levels, resources, instructional roles, activities and procedures, evaluation, and follow-up are described for…

  6. A Common Polymorphism within the IGF2 Imprinting Control Region Is Associated with Parent of Origin Specific Effects in Infantile Hemangiomas

    PubMed Central

    Schultz, Brent; Yao, Xiaopan; Deng, Yanhong; Waner, Milton; Spock, Christopher; Tom, Laura; Persing, John; Narayan, Deepak

    2015-01-01

    Infantile hemangioma (IH) is the most common tumor of the pediatric age group, affecting up to 4% of newborns ranging from inconsequential blemishes, to highly aggressive tumors. Following well defined growth phases (proliferative, plateau involutional) IH usually regress into a fibro-fatty residuum. Despite the high prevalence of IH, little is known regarding the pathogenesis of disease. A reported six fold decrease in IGF2 expression (correlating with transformation of proliferative to involuted lesions) prompted us to study the IGF-2 axis further. We demonstrate that IGF2 expression in IH is strongly related to the expression of a cancer testes and suspected oncogene BORIS (paralog of CTCF), placing IH in the unique category of being the first known benign BORIS positive tumor. IGF2 expression was strongly and positively related to BORIS transcript expression. Furthermore, a stronger association was made when comparing BORIS levels against the expression of CTCF via either a percentage or difference between the two. A common C/T polymorphism at CTCF BS6 appeared to modify the correlation between CTCF/BORIS and IGF2 expression in a parent of origin specific manner. Moreover, these effects may have phenotypic consequences as tumor growth also correlates with the genotype at CTCF BS6. This may provide a framework for explaining the clinical variability seen in IH and suggests new insights regarding CTCF and BORIS related functionality in both normal and malignant states. PMID:26496499

  7. Arts/Crafts.

    ERIC Educational Resources Information Center

    Instructor, 1980

    1980-01-01

    Described are various arts and crafts ideas, mostly with a February theme. Included are: ceramic boxes, valentine ideas, and patriotic projects--symbols of our country, silhouettes of George Washington and Abraham Lincoln, and stars and stripes. (KC)

  8. Tutorials for Africa - Diarrhea: MedlinePlus

    MedlinePlus

    ... Judith Allsaints Apio Chaudhari Mugdha Ramachandra Richard Lunyata Peter Agaba Elizabeth Nakabuye Team of medical students in ... Valentine Kahababo Art and audio team - Kampala, Uganda Peter Mukiibi Kenneth Nek Daniel Hama Contact the Makerere ...

  9. Tutorials for Africa - Malaria: MedlinePlus

    MedlinePlus

    ... Judith Allsaints Apio Chaudhari Mugdha Ramachandra Richard Lunyata Peter Agaba Elizabeth Nakabuye Team of medical students in ... Valentine Kahababo Art and audio team - Kampala, Uganda Peter Mukiibi Kenneth Nek Daniel Hama Contact the Makerere ...

  10. Tutorials for Africa - Diarrhea: MedlinePlus

    MedlinePlus

    ... Team Education and Service Program Makerere University, Kampala, Uganda Dean Nelson Sewankambo, MD, PhD Ian Munabi, MD ... MSC Valentine Kahababo Art and audio team - Kampala, Uganda Peter Mukiibi Kenneth Nek Daniel Hama Contact the ...

  11. 76 FR 21622 - IFR Altitudes; Miscellaneous Amendments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-18

    ... ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034; February 26, 1979); and (3) does... 17500 THEDFORD, NE VOR/DME MARSS, NE FIX 4900 17500 MARSS, NE FIX VALENTINE, NE NDB 4800 17500...

  12. Optimized Battery-Type Reactor Primary System Design Utilizing Lead

    SciTech Connect

    Yu, Yong H.; Son, Hyoung M.; Lee, Il S.; Suh, Kune Y.

    2006-07-01

    A number of small and medium size reactors are being developed worldwide as well as large electricity generation reactors for co-generation, district heating or desalination. The Seoul National University has started to develop 23 MWth BORIS (Battery Optimized Reactor Integral System) as a multi-purpose reactor. BORIS is an integral-type optimized fast reactor with an ultra long life core. BORIS is being designed to meet the Generation IV nuclear energy system goals of sustainability, safety, reliability and economics. Major features of BORIS include 20 consecutive years of operation without refueling; elimination of an intermediate heat transport loop and main coolant pump; open core without individual subassemblies; inherent negative reactivity feedback; and inherent load following capability. Its one mission is to provide incremental electricity generation to match the needs of developing nations and especially remote communities without major electrical grid connections. BORIS consists of a reactor module, heat exchanger, coolant module, guard vessel, reactor vessel auxiliary cooling system (RVACS), secondary system, containment and the seismic isolation. BORIS is designed to generate 10 MWe with the resulting thermal efficiency of 45 %. BORIS uses lead as the primary system coolant because of the inherent safety of the material. BORIS is coupled with a supercritical carbon dioxide Brayton cycle as the secondary system to gain a high cycle efficiency in the range of 45 %. The reference core consists of 757 fuel rods without assembly with an active core height of 0.8 m. The BORIS core consists of single enrichment zone composed of a Pu-MA (minor actinides)-U-N fuel and a ferritic-martensitic stainless steel clad. This study is intended to set up appropriate reactor vessel geometry by performing thermal hydraulic analysis on RVACS using computational fluid dynamics codes; to examine the liquid metal coolant behavior along the subchannels; to find out whether the

  13. Public Library YA Program Roundup. VOYA's Most Valuable Program 2002: Munching on Books; Really Getting Graphic: A Teen Read Week Art Show Preview; Masquerades and Millionaires: An After-hours Teen Extravaganza; Teen Time Travelers Make Listening a "Hobbit"; Teens Take a Humongous Bite Out of Newly Seasoned Reading Program; Putting a Stake through Valentine's Day; Celebrating the Day of the Dead; Legos in the Library Window; "So that You May Know": Teen Rading Group Meets Holocaust Survivors.

    ERIC Educational Resources Information Center

    Falck, Kara; Kan, Kat; Fletcher-Spear, Kristin; Solomon, Beth B.; Dunford, Karen; Rinella, Kay Walsh; Shenoy, Ravi; McIntosh, Jennifer R.; Socha, Debbie; Dudeck, Sharon; Duwel, Lucretia; Stackpole, Diane; Blosveren, Barbara

    2002-01-01

    These nine articles describe public library programs for young adults. Highlights include a read-a-thon with snacks; graphic novels and art; costume party and trivia contest; activities based on "The Hobbit"; a summer reading program that included teen volunteers; writing epitaphs for Day of the Dead celebration; Legos displays; and meeting with…

  14. BOREAS Forest Cover Data Layers over the SSA-MSA in Raster Format

    NASA Technical Reports Server (NTRS)

    Nickeson, Jaime; Gruszka, F; Hall, F.

    2000-01-01

    This data set, originally provided as vector polygons with attributes, has been processed by BORIS staff to provide raster files that can be used for modeling or for comparison purposes. The original data were received as ARC/INFO coverages or as export files from SERM. The data include information on forest parameters for the BOREAS SSA-MSA. Most of the data used for this product were acquired by BORIS in 1993; the maps were produced from aerial photography taken as recently as 1988. The data are stored in binary, image format files.

  15. BOREAS Elevation Contours over the NSA and SSA in ARC/INFO Generate Format

    NASA Technical Reports Server (NTRS)

    Knapp, David; Nickeson, Jaime; Hall, Forrest G. (Editor)

    2000-01-01

    This data set was prepared by BORIS Staff by reformatting the original data into the ARC/INFO Generate format. The original data were received in SIF at a scale of 1:50,000. BORIS staff could not find a format document or commercial software for reading SIF; the BOREAS HYD-08 team pro-vided some C source code that could read some of the SIF files. The data cover the BOREAS NSA and SSA. The original data were compiled from information available in the 1970s and 1980s. The data are available in ARC/INFO Generate format files.

  16. Navier-Stokes Neutral and Plasma Fluid Modelling in 3D

    SciTech Connect

    Riemann, J; Borchardt, M; Schneider, R; Mutzke, A; Rognlien, T; Umansky, M

    2004-05-17

    The 3D finite volume transport code BoRiS is applied to a system of coupled plasma and neutral fluid equations in a slab. Demonstrating easy implementation of new equations, a new parallel BoRiS version is tested on three different models for the neutral fluid - diffusive, parallel Navier-Stokes and full Navier-Stokes - and the results are compared to each other. Typical effects like density enhancement by ionization of recycled neutrals in front of a target plate can be seen and differences are linked to the neutral models in use.

  17. Developing Professional-Level Language Proficiency.

    ERIC Educational Resources Information Center

    Leaver, Betty Lou, Ed.; Shekhtman, Boris, Ed.

    This collection of papers examines approaches to teaching near-native ability in foreign languages. The 13 papers focus on the following: (1) "Principles and Practices in Teaching Superior-Level Language Skills: Not Just More of the Same" (Betty Lou Leaver and Boris Shekhtman); (2) "Toward Academic Level Foreign Language Abilities: Reconsidering…

  18. Traduction et langues de specialite: Approches theoriques et considerations pedagogiques (Translation and Specialty Languages: Theoretical Approaches and Pedagogic Considerations).

    ERIC Educational Resources Information Center

    Guevel, Zelie, Ed.; Valentine, Egan, Ed.

    Essays on the teaching of translation and on specialized translation, all in French, include: "Perspectives d'optimisation de la formation du traducteur: quelques reflexions" ("Perspectives on Optimization of Training of Translation Teachers: Some Reflections") (Egan Valentine); "L'enseignement de la revision pedagogique" ("The Teaching of…

  19. 75 FR 47252 - Proposed Establishment of Low Altitude Area Navigation Routes (T-281, T-283, T-285, T-286, and T...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-05

    ... ``significant rule'' under Department of ] Transportation (DOT) Regulatory Policies and Procedures (44 FR 11034... continues to read as follows: Authority: 49 U.S.C. 106(g), 40103, 40113, 40120; E.O. 10854, 24 FR 9565, 3...'09'' W.) MARSS, NE Fix (Lat. 42 27'49'' N., long. 100 36'15'' W.) Valentine, NE (VTN) NDB (Lat. 42...

  20. Antioxidant activity, phenolic and anthocyanin contents of various rhubarb (Rheum-spp.) varieties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antioxidant activity (ABTS assay), total phenolics, and total anthocyanins were determined in the petioles of fifteen rhubarb (Rheum spp.) varieties. Antioxidant activity ranged from 491 ± 60 (Victoria 574/27) to 1820 'mol Trolox/g DW (Valentine). The phenolic content varied from 673 ± 41 (Loher Blu...

  1. Staphylococcus pseudintermedius necrotizing fasciitis in a dog

    PubMed Central

    Weese, J. Scott; Poma, Roberta; James, Fiona; Buenviaje, Gilbert; Foster, Robert; Slavic, Durda

    2009-01-01

    Staphylococcus pseudintermedius was implicated as the cause of rapidly progressive and fatal necrotizing fasciitis in a dog. The isolate was methicillin-susceptible and did not contain genes encoding the Panton-Valentine leukocidin. While Streptococcus canis is typically considered to be the main cause of necrotizing fasciitis in dogs, staphylococci should also be considered. PMID:19721787

  2. What's Happening in February?

    ERIC Educational Resources Information Center

    Weissman, Ron; And Others

    Brief information is given on 12 February events celebrated by Puerto Ricans: Groundhog Day; Candlemas; St. Valentine's Day; Mardi Gras; Ash Wednesday; Black History; and the birthdays of Thomas Alva Edison, Abraham Lincoln, Susan B. Anthony, Julia de Burgos, Luis Munoz Marin, and George Washington. Designed as a teacher resource, the booklet…

  3. 77 FR 61597 - Avalon Wind, LLC; Avalon Wind 2, LLC; Catalina Solar, LLC; Catalina Solar 2, LLC; Pacific Wind...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-10

    ... Energy Regulatory Commission Avalon Wind, LLC; Avalon Wind 2, LLC; Catalina Solar, LLC; Catalina Solar 2, LLC; Pacific Wind Lessee, LLC; Pacific Wind 2, LLC; Valentine Solar, LLC; EDF Renewable Development, Inc.; Notice of Petition for Declaratory Order Take notice that on September 27, 2012, Avalon...

  4. DISPOSITION OF BROMODICHLOROMETHANE IN HUMANS FOLLOWING ORAL AND DERMAL EXPOSURE

    EPA Science Inventory

    DISPOSITION OF BROMODICHLOROMETHANE IN HUMANS FOLLOWING ORAL AND DERMAL EXPOSURE. TL Leavens1, MW Case1, RA Pegram1, BC Blount2, DM DeMarini1, MC Madden1, and JL Valentine3. 1NHEERL, USEPA, RTP, NC, USA; 2CDC, Atlanta, GA, USA; 3RTI, RTP, NC, USA.
    The disinfection byproduct ...

  5. Football or Physics?

    ERIC Educational Resources Information Center

    Handorf, William C.

    2007-01-01

    In this article, the author discusses the United States commemorative stamps and what the stamp-buying public knows about higher education. United States commemorative stamps have illustrated individuals such as Marilyn Monroe (1995); characters such as Bugs Bunny (1997); American motorcycles (2006); and Valentine candy hearts (2004). Higher…

  6. Chemistry with Inexpensive Materials: Spray Bottles and Plastic Bags.

    ERIC Educational Resources Information Center

    Zoltewicz, Susan

    1993-01-01

    Presents eight chemistry activities that are interesting and involve simple, easily available materials. Topics include mystery writing, valentine hearts, flame tests, evaporation race, buoyancy versus mass, determination of relative masses of gases, mole sample container, and cold and hot packs. (DDR)

  7. Creeping bentgrass putting green response to foliar nitrogen fertilization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ABSTRACT In 2009 and 2010, three independent fertility trials were conducted on a putting green (PG) managed within the Pennsylvania State University Joseph Valentine Turfgrass Research Center (University Park, PA). The objective was to identify Penn A-1/A-4 creeping bentgrass putting green quality ...

  8. February Folklore: You'll Love It in Your Curriculum.

    ERIC Educational Resources Information Center

    Gale, David

    1980-01-01

    Folk tales which are particularly suited to February cover legends about George Washington, the Chinese zodiac, and Groundhog Day. Also included is a calendar of activities for February. These activities are appropriate for Groundhog Day, Valentine's Day, Chinese New Year, President's (Washington and Lincoln) Day, and Leap Year. (KC)

  9. “More than skin deep”: Recurrent primary hand abscesses in a warehouse operative

    PubMed Central

    Kearney, L.; O’Connor, C.; Fitzpatrick, F.; O’Sullivan, J. B.

    2015-01-01

    A 25-year-old male right-hand dominant warehouse operator presented with two hand infections within 12 weeks both requiring surgical drainage and antimicrobial therapy. Subsequent testing confirmed Panton-Valentine leukocidin-positive Staphylococcus aureus (PVL-SA). This case highlights the need for prompt multidisciplinary management of hand infections to consider, diagnose and manage atypical infections.

  10. A Multidimensional Scaling Analysis of Own- and Cross-Race Face Spaces

    ERIC Educational Resources Information Center

    Papesh, Megan H.; Goldinger, Stephen D.

    2010-01-01

    We examined predictions derived from Valentine's (1991) Multidimensional Space (MDS) framework for own- and other-race face processing. A set of 20 computerized faces was generated from a single prototype. Each face was saved as Black and White, changing only skin tone, such that structurally identical faces were represented in both race…

  11. Relational Framing Theory and Coming-Out Narratives: A Data Analysis Activity

    ERIC Educational Resources Information Center

    Helens-Hart, Rose

    2015-01-01

    Coming-out scenarios have been described as potentially traumatic events that change the parent-child relationship (MacDonald, 1983). Little research in the field of communication studies has been conducted on how the process of coming out unfolds within families (Valentine, Skelton, & Butler, 2003). The exercise described in this article…

  12. Holidays. Instructional Media Advisory List.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh. Div. of Media Evaluation Service.

    This annotated bibliography is directed at teachers of students in grades preK-6 and covers books about holidays. The holidays for which materials are listed are: Christmas, Easter, Halloween, Hanukkah, Passover, Purim, Rosh Hashanah, Sukkot, Thanksgiving, and Valentine's Day. A directory of publishers from whom these items are available is…

  13. Goal Attainment Scaling as an Effective Strategy to Assess the Outcomes of Mentoring Programs for Troubled Youth

    ERIC Educational Resources Information Center

    Balcazar, Fabricio E.; Davies, Gethin L.; Viggers, Dave; Tranter, Gary

    2006-01-01

    Mentoring programs are increasingly popular as preventive and/or supportive interventions for youth with various needs. A meta-analysis of mentoring program effects conducted by DuBois, Holloway, Valentine, and Cooper (2002) suggests that youth from backgrounds of risk (defined broadly) have the capacity to benefit from mentoring, especially when…

  14. Effective Teaching and Student Engagement in the College Classroom: Using the Instructional Practices Inventory (IPI) as a Tool for Peer Observation and Self-Reflection

    ERIC Educational Resources Information Center

    Hunzicker, J.; Lukowiak, T.

    2012-01-01

    The authors present initial findings from a collaborative self-study exploring student engagement as a measure of teaching effectiveness. Focused on their college classrooms during one semester, the study pilots a peer observation model of the Instructional Practices Inventory (IPI) (Valentine, 2005). Data collection included IPI codes, anecdotal…

  15. Post-Secondary Youth and Adult Learning [and] Educational Marketing and Delivery Systems. Trustees' Symposium on Postsecondary Education, Programs Two and Three.

    ERIC Educational Resources Information Center

    Hunter, Walter E., Ed.

    This is the report of a conference held to communicate the results of the Non Traditional Community College Project conducted during 1973-74 to determine the potential learning population of metropolitan St. Louis. The conference report consists of major presentations by J. A. Valentine of the College Entrance Examination Board and by the…

  16. Eventos de Febrero (February Events).

    ERIC Educational Resources Information Center

    Toro, Leonor; Pla, Myrna

    Designed as a resource for teachers, the booklet contains brief information on eight events celebrated by Puerto Ricans in the month of February: La Candelaria; Abraham Lincoln; Black History; Valentine's Day; Julia de Burgos; Luis Munoz Marin; George Washington; and the Carnaval. Written in Spanish, the booklet discusses the orgin and ways of…

  17. Courtside: NCLB=New Cause for Litigious Behavior

    ERIC Educational Resources Information Center

    Zirkel, Perry A.

    2004-01-01

    In September 2002, the children of parents Latasha Gibbs, Carmella Glass, Laverne Jones, Charlene Mingo, Deborah Powell-Jasper, Eunice Staton, and Keikola Valentine were attending New York City public schools that the state education department identified as needing improvement -- in other words, failing -- under the No Child Left Behind (NCLB)…

  18. The Leonid Fireball Night from Romania

    NASA Astrophysics Data System (ADS)

    Grigore, V.; Berinde, S.

    1999-02-01

    An overview of the 1998 Leonid activity as seen from Romania by SARM members, with a description of the event on November 16-17 as seen by Valentin Grigore (GRIVA) at Targoviste, lambda=25deg 29' 00'' E, phi=44deg 57' 18'' N, h=350m.

  19. Music Curriculum for Kindergarten.

    ERIC Educational Resources Information Center

    Picht, Harriet

    This kindergarten music curriculum provides a year-long program of a sequenced series of activities designed to develop music concepts. Topics of the units in this guide are: self-concept (beginning of the year), fall, Halloween, Thanksgiving, Christmas, winter, a circus, Valentine's Day, spring, and farms. A scope and sequence chart of concepts…

  20. Celebrating Traditional Holidays in Public Schools: Books for Basic Values.

    ERIC Educational Resources Information Center

    Ahern, John F.; Moir, Hughes

    1986-01-01

    Provides a brief annotated bibliography of children's books which may be used to foster greater understanding of the five most popular holidays celebrated in U. S. public schools. The holidays are Columbus Day, Halloween, Thanksgiving, Christmas, and St. Valentine's Day. (JDH)

  1. What Works for Me.

    ERIC Educational Resources Information Center

    Vishwanadha, Hari; And Others

    1990-01-01

    Provides suggestions on various English instruction topics. Includes (1) "Argumentation Exercise," Hari Vishwanadha; (2) "How to Survive Developmental (or Any Other) English," Sally Russell; (3) "Reach Out to an Expert," Norma A. Register; (4) "Summary and Response Writing," Alec Valentine; (5) "The Living Journal," Blair Spencer Ray; and (6)…

  2. 76 FR 8808 - Supplemental Final Environmental Impact Statement: Clark County, Indiana, and Jefferson County, KY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ... County, Indiana and Jefferson County, Kentucky. FOR FURTHER INFORMATION CONTACT: Mr. Duane Thomas..., and Jefferson County, KY AGENCY: Federal Highway Administration (FHWA), DOT. ACTION: Notice of intent... Frankfort, KY 40601, Telephone: (502) 223-6720, e-mail: Duane.Thomas@dot.gov or Mr. Gary Valentine,...

  3. Holidays. Advisory List: Instructional Media.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh. Media and Technology Services.

    This document presents an annotated bibliography of instructional materials that deal with subjects relating to holidays. Topics include Christmas, Earth Day, Easter, Halloween, Hannukah, Independence Day, Martin Luther King Day, Thanksgiving, Valentine's Day, and "More than One Holiday." Works cited include illustrated stories, poems, songs, and…

  4. Multiplex Real-Time PCR Assay for Detection of Methicillin-Resistant Staphylococcus aureus and Associated Toxin Genes▿

    PubMed Central

    Fosheim, G. E.; Nicholson, A. C.; Albrecht, V. S.; Limbago, B. M.

    2011-01-01

    We describe a real-time PCR assay for the detection of methicillin-resistant Staphylococcus aureus and genes encoding toxic shock syndrome toxin 1 and Panton-Valentine leukocidin. Rapid screening and detection of toxins is a useful tool for surveillance studies and outbreak investigations involving large numbers of isolates. PMID:21697325

  5. Insecure? Keeping New England Campuses Safe

    ERIC Educational Resources Information Center

    Franzosa, Alyssa

    2009-01-01

    On April 16, 2007, Seung-Hui Cho traded in his title as "student" for one of "gunman." That day, Cho, a student at Virginia Tech, was responsible for the deadliest shooting spree by a single person in U.S. history, killing 33 people, including himself. Ten months later on Valentine's Day, Steven Kazmierczak joined Cho in the ranks of student…

  6. Photoproduction of Carbon Monoxide from Natural Organic Matter

    EPA Science Inventory

    Pioneering studies by Valentine provided early kinetic results that used carbon monoxide (CO) production to evaluate the photodecomposition of aquatic natural organic matter (NOM) . (ES&T 1993 27 409-412). Comparatively few kinetic studies have been conducted of the photodegradat...

  7. New Perspectives in Human Resource Development.

    ERIC Educational Resources Information Center

    1999

    These three papers are from a symposium on new perspectives in human resource development (HRD). "Developing an Instrument to Measure the Use of Play-Based Training Methods in Healthcare Education" (Rebecca J. Adams, Karen E. Watkins, Tom Valentine) reports preliminary findings from a pilot study that tested data collection procedures and the…

  8. 75 FR 63501 - Buy American Exceptions Under the American Recovery and Reinvestment Act of 2009

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-15

    ... section 1605(c) of the Recovery Act and OMB's implementing guidance published on April 23, 2009 (74 FR... energy efficient bathroom exhaust fans and linoleum flooring for the Fairmont Street, Valentine Street... was granted by HUD on the basis that the relevant manufactured goods (energy efficient...

  9. Evaluating Principals. Research Roundup.

    ERIC Educational Resources Information Center

    Andrews, Carl

    1990-01-01

    Five recent studies included in this annotated bibliography highlight the diverse facets of an effective principal evaluation system. A technical report by Jerry W. Valentine and Michael L. Bowman includes a clinical instrument for assessing teachers' perception of principals' effectiveness. In a second report, Daniel L. Duke and Richard J.…

  10. Using Meta-Analysis to Explain Variation in Head Start Research Results: The Role of Research Design

    ERIC Educational Resources Information Center

    Shager, Hilary M.; Schindler, Holly S.; Hart, Cassandra M.D.; Duncan, Greg J.; Magnuson, Katherine A.; Yoshikawa, Hirokazu

    2010-01-01

    Head Start was designed as a holistic intervention to improve economically disadvantaged, preschool-aged children's cognitive and social development by providing a comprehensive set of educational, health, nutritional, and social services, as well as opportunities for parent involvement (Zigler & Valentine, 1979). Given the current interest in ECE…

  11. Numerical modeling of cavitational resonant oscillations of a liquid

    NASA Astrophysics Data System (ADS)

    Iakovtsov, A. V.

    Using the method of differential approximation, the dispersion characteristics of the Lax-Wendroff (LW) schemes and LW schemes with correction of Boris-Book flows are analyzed. It is shown that the combined Lax-Wendroff-Boris-Books scheme is capable of suppressing variance errors. Several fluid models are analyzed. Using three models of the combined scheme, the induced oscillations of a water column are calculated, and it is shown that the amplitude-frequency characteristics of oscillations calculated using a model of a liquid with bubbles are in good agreement with experimental data. Special attention is given to estimating boundary conditions and to determinations of the behavior of an oscillation process with increasing excitation frequencies.

  12. BOREAS Level-4b AVHRR-LAC Ten-Day Composite Images: At-sensor Radiance

    NASA Technical Reports Server (NTRS)

    Cihlar, Josef; Chen, Jing; Nickerson, Jaime; Newcomer, Jeffrey A.; Huang, Feng-Ting; Hall, Forrest G. (Editor)

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study (BOREAS) Staff Science Satellite Data Acquisition Program focused on providing the research teams with the remotely sensed satellite data products they needed to compare and spatially extend point results. Manitoba Remote Sensing Center (MRSC) and BOREAS Information System (BORIS) personnel acquired, processed, and archived data from the Advanced Very High Resolution Radiometer (AVHRR) instruments on the National Oceanic and Atmospheric Administration (NOAA-11) and -14 satellites. The AVHRR data were acquired by CCRS and were provided to BORIS for use by BOREAS researchers. These AVHRR level-4b data are gridded, 10-day composites of at-sensor radiance values produced from sets of single-day images. Temporally, the 10- day compositing periods begin 11-Apr-1994 and end 10-Sep-1994. Spatially, the data cover the entire BOREAS region. The data are stored in binary image format files.

  13. BOREAS Level-4c AVHRR-LAC Ten-Day Composite Images: Surface Parameters

    NASA Technical Reports Server (NTRS)

    Cihlar, Josef; Chen, Jing; Huang, Fengting; Nickeson, Jaime; Newcomer, Jeffrey A.; Hall, Forrest G. (Editor)

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study (BOREAS) Staff Science Satellite Data Acquisition Program focused on providing the research teams with the remotely sensed satellite data products they needed to compare and spatially extend point results. Manitoba Remote Sensing Center (MRSC) and BOREAS Information System (BORIS) personnel acquired, processed, and archived data from the Advanced Very High Resolution Radiometer (AVHRR) instruments on the NOAA-11 and -14 satellites. The AVHRR data were acquired by CCRS and were provided to BORIS for use by BOREAS researchers. These AVHRR level-4c data are gridded, 10-day composites of surface parameters produced from sets of single-day images. Temporally, the 10-day compositing periods begin 11-Apr-1994 and end 10-Sep-1994. Spatially, the data cover the entire BOREAS region. The data are stored in binary image format files. Note: Some of the data files on the BOREAS CD-ROMs have been compressed using the Gzip program.

  14. Meteor Beliefs Project: Meteoric imagery in SF, Part II - H. P. Lovecraft's The Colour Out Of Space

    NASA Astrophysics Data System (ADS)

    McBeath, Alastair; Gheorghe, Andrei Dorian

    2005-12-01

    A brief biography of American horror-fiction writer H. P. Lovecraft (1890-1937) precedes details from his story `The Colour Out Of Space', concerning a deadly life-form brought to Earth in a meteorite. This allows a comparison with details from the 1965 film derived from this tale, `Die, Monster, Die!', featuring the great horror actor Boris Karloff in one of his last, best roles.

  15. KKG Group Paraffin Removal

    SciTech Connect

    Schulte, Ralph

    2001-12-01

    The Rocky Mountain Oilfield Testing Center (RMOTC) has recently completed a test of a paraffin removal system developed by the KKG Group utilizing the technology of two Russian scientists, Gennady Katzyn and Boris Koggi. The system consisting of chemical ''sticks'' that generate heat in-situ to melt the paraffin deposits in oilfield tubing. The melted paraffin is then brought to the surface utilizing the naturally flowing energy of the well.

  16. Nonperturbative relativistic calculation of the muonic hydrogen spectrum

    SciTech Connect

    Carroll, J. D.; Thomas, A. W.; Rafelski, J.; Miller, G. A.

    2011-07-15

    We investigate the muonic hydrogen 2P{sub 3/2}{sup F=2} to 2S{sub 1/2}{sup F=1} transition through a precise, nonperturbative numerical solution of the Dirac equation including the finite-size Coulomb force and finite-size vacuum polarization. The results are compared with earlier perturbative calculations of (primarily) [E. Borie, Phys. Rev. A 71, 032508 (2005); E. Borie and G. A. Rinker, Rev. Mod. Phys. 54, 67 (1982); E. Borie, Z. Phys. A 275, 347 (1975) and A. P. Martynenko, Phys. Rev. A 71, 022506 (2005); A. Martynenko, Phys. At. Nucl. 71, 125 (2008), and K. Pachucki, Phys. Rev. A 53, 2092 (1996)] and experimental results recently presented by Pohl et al.[Nature (London) 466, 213 (2010)], in which this very comparison is interpreted as requiring a modification of the proton charge radius from that obtained in electron scattering and electronic hydrogen analyses. We find no significant discrepancy between the perturbative and nonperturbative calculations, and we present our results as confirmation of the perturbative methods.

  17. "U-X-L Encyclopedia of U. S. History" Hones Students' Subject Search and Indexing Skills

    ERIC Educational Resources Information Center

    Krueger, Karla

    2010-01-01

    This article features the "U-X-L Encyclopedia of U.S. History" by Sonia Benson, Daniel E. Brannen, Jr., and Rebecca Valentine is a new eight-volume set available in print or ebook (2009). The set has 1,745 pages and 677 entries ranging from just under one page to around eight pages in length. The ebook option may be accessed through Gale Virtual…

  18. Back pain in a previously healthy teenager.

    PubMed

    Fitzgerald, Felicity; Howard, Julia; Bailey, Fiona; Soleimanian, Sorrush

    2013-01-01

    We present the case of a 14-year-old previously healthy boy who presented to his general practitioner with back pain and fever after rugby training. He was initially treated for suspected discitis but during the course of his admission he rapidly deteriorated and developed severe necrotising pneumonia. He was intubated, ventilated and transferred to a paediatric intensive care unit. Panton-Valentine leukocidin Staphylococcus aureus was suspected and subsequently identified in blood cultures. PMID:23867883

  19. Division II: Commission 10: Solar Activity

    NASA Astrophysics Data System (ADS)

    van Driel-Gesztelyi, Lidia; Scrijver, Karel J.; Klimchuk, James A.; Charbonneau, Paul; Fletcher, Lyndsay; Hasan, S. Sirajul; Hudson, Hugh S.; Kusano, Kanya; Mandrini, Cristina H.; Peter, Hardi; Vršnak, Bojan; Yan, Yihua

    2015-08-01

    The Business Meeting of Commission 10 was held as part of the Business Meeting of Division II (Sun and Heliosphere), chaired by Valentin Martínez-Pillet, the President of the Division. The President of Commission 10 (C10; Solar activity), Lidia van Driel-Gesztelyi, took the chair for the business meeting of C10. She summarised the activities of C10 over the triennium and the election of the incoming OC.

  20. Establishment of ST30 as the predominant clonal type among community-associated methicillin-resistant Staphylococcus aureus isolates in Singapore.

    PubMed

    Hsu, Li-Yang; Koh, Yin-Ling; Chlebicka, Nidhi Loomba; Tan, Thean-Yen; Krishnan, Prabha; Lin, Raymond Tzer-Pin; Tee, Nancy; Barkham, Timothy; Koh, Tse-Hsien

    2006-03-01

    The number of infections attributable to community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in Singapore is progressively increasing. Most cases in the past 2 years were caused by Panton-Valentine leukocidin-positive isolates belonging to sequence type 30, according to multilocus sequence typing. This has clearly become the predominant sequence type among CA-MRSA isolates in Singapore. PMID:16517901

  1. Geological Interpretation of Bathymetric and Backscatter Imagery of the Sea Floor off Eastern Cape Cod, Massachusetts

    USGS Publications Warehouse

    Poppe, Larry J.; Paskevich, Valerie F.; Butman, Bradford; Ackerman, Seth D.; Danforth, William W.; Foster, Dave S.; Blackwood, Dann S.

    2006-01-01

    The imagery, interpretive data layers, and data presented herein were derived from multibeam echo-sounder data collected off Eastern Cape Cod, Massachusetts, and from the stations occupied to verify these acoustic data. The basic data layers show sea-floor topography, sun-illuminated shaded relief, and backscatter intensity; interpretive layers show the distributions of surficial sediment and sedimentary environments. Presented verification data include new and historical sediment grain-size analyses and a gallery of still photographs of the seabed. The multibeam data, which cover a narrow band of the sea floor extending from Provincetown around the northern tip of Cape Cod and south southeastward to off Monomoy Island, were collected during transits between concurrent mapping projects in the Stellwagen Bank National Marine Sanctuary (Valentine and others, 2001; Butman and others, 2004; and Valentine, 2005) and Great South Channel (Valentine and others, 2003a, b, c, d). Although originally collected to maximize the use of time aboard ship, these data provide a fundamental framework for research and management activities in this part of the Gulf of Maine (Noji and others, 2004), show the composition and terrain of the seabed, and provide information on sediment transport and benthic habitat. These data and interpretations also support ongoing modeling studies of the lower Cape's aquifer system (Masterson, 2004) and of erosional hotspots along the Cape Cod National Seashore (List and others, 2006).

  2. Supercritical Carbon Dioxide Brayton Power Conversion Cycle Design for Optimized Battery-Type Integral Reactor System

    SciTech Connect

    Kim, Won J.; Kim, Tae W.; Sohn, Myoung S.; Suh, Kune Y.

    2006-07-01

    Supercritical carbon dioxide (SCO{sub 2}) promises a high power conversion efficiency of the recompression Brayton cycle due to its excellent compressibility reducing the compression work at the bottom of the cycle and to a higher density than helium or steam decreasing the component size. Therefore, the high SCO{sub 2} Brayton cycle efficiency as high as 45 % furnishes small sized nuclear reactors with economical benefits on the plant construction and maintenance. A 23 MWth BORIS (Battery Optimized Reactor Integral System) is being developed as a multipurpose reactor. BORIS, an integral-type optimized fast reactor with an ultra long life core, is coupled to the SCO{sub 2} Brayton cycle needing less room relative to the Rankine steam cycle because of its smaller components. The SCO{sub 2} Brayton cycle of BORIS consists of a 16 MW turbine, a 32 MW high temperature recuperator, a 14 MW low temperature recuperator, an 11 MW pre-cooler and 2 and 2.8 MW compressors. Entering six heat exchangers between primary and secondary system at 19.9 MPa and 663 K, the SCO{sub 2} leaves the heat exchangers at 19.9 MPa and 823 K. The promising secondary system efficiency of 45 % was calculated by a theoretical method in which the main parameters include pressure, temperature, heater power, the turbine's, recuperators' and compressors' efficiencies, and the flow split ratio of SCO{sub 2} going out from the low temperature recuperator. Test loop SOLOS (Shell-and-tube Overall Layout Optimization Study) is utilized to develop advanced techniques needed to adopt the shell-and-tube type heat exchanger in the secondary loop of BORIS by studying the SCO{sub 2} behavior from both thermal and hydrodynamic points of view. Concurrently, a computational fluid dynamics (CFD) code analysis is being conducted to develop an optimal analytical method of the SCO{sub 2} turbine efficiency having the parameters of flow characteristics of SCO{sub 2} passing through buckets of the turbine. These

  3. BOREAS RSS-14 Level-1a GOES-8 Visible, IR and Water Vapor Images

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Newcomer, Jeffrey A.; Faysash, David; Cooper, Harry J.; Smith, Eric A.

    2000-01-01

    The BOREAS RSS-14 team collected and processed several GOES-7 and GOES-8 image data sets that covered the BOREAS study region. The level-1a GOES-8 images were created by BORIS personnel from the level-1 images delivered by FSU personnel. The data cover 14-Jul-1995 to 21-Sep-1995 and 12-Feb-1996 to 03-Oct-1996. The data start out as three bands with 8-bit pixel values and end up as five bands with 10-bit pixel values. No major problems with the data have been identified. The differences between the level-1 and level-1a GOES-8 data are the formatting and packaging of the data. The images missing from the temporal series of level-1 GOES-8 images were zero-filled by BORIS staff to create files consistent in size and format. In addition, BORIS staff packaged all the images of a given type from a given day into a single file, removed the header information from the individual level-1 files, and placed it into a single descriptive ASCII header file. The data are contained in binary image format files. Due to the large size of the images, the level-1a GOES-8 data are not contained on the BOREAS CD-ROM set. An inventory listing file is supplied on the CD-ROM to inform users of what data were collected. The level-1a GOES-8 image data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). See sections 15 and 16 for more information. The data files are available on a CD-ROM (see document number 20010000884).

  4. STS-106 Crew Activities Report/Flight Day 9 Highlights

    NASA Technical Reports Server (NTRS)

    2000-01-01

    On this ninth day of the STS-106 Atlantis mission, the flight crew, Commander Commander Terrence W. Wilcutt, Pilot Scott D. Altman, and Mission Specialists Daniel C. Burbank, Edward T. Lu, Richard A. Mastracchio, Yuri Ivanovich Malenchenko, and Boris V. Morukov are shown transferring supplies and equipment. Equipment includes an exercise treadmill, for use by the first resident crew. Altman, Lu, Burbank and Morukov are seen installing the treadmill in the Zvezda module. Footage also shows Lu and Altman participating in a telecommunication interview. A beautiful night shot of the International Space Station (ISS) and Atlantis complex above the Earth is also shown.

  5. [Morphological diversity of Pandorina morum (Mull.) Vory (Volvocaceae) colonies].

    PubMed

    Voĭtekhovskiĭ, Iu L

    2001-01-01

    Morphological variability of polyhedral colonies of green algae (Volvocaceae) were studied using some elements of combinative theory of polyhedron and the theory of diophantine equations. These colonies are considered as results of self-organization according to topological regularities of sphere dissection by convex polygons. It was shown that in three-dimensional Euclidean space for each colony of Pandorina morum (Müll.) Bory only three different forms are possible. One of them has no plane of symmetry and, thus, has two enantiomorphous varieties. It is suggested that frequency spectrum of forms can be used as potential indicator of environment pollution. PMID:11605552

  6. Risk of Low Dose/Low Dose Rate Ionizing Radiation to Humans Symposium at the EMS 2009 Annual Meeting - September 2006

    SciTech Connect

    Morgan, William F.; von Borstel, Robert C.; Brenner, David; Redpath, J. Leslie; Erickson, Barbra E.; Brooks, Antone L.

    2009-11-12

    The low dose symposium thoughtfully addressed controversy of risk from low dose radiation exposure, hormesis and radon therapy. The stem cell symposium cogently considered the role of DNA damage and repair in hematopoietic stem cells underlying aging and malignancy and provocatively presented evidence that stem cells may have distinct morphologies and replicative properties, as well as special roles in cancer initiation. In the epigenetics symposium, studies illustrated the long range interaction of epigenetic mechanisms, the roles of CTCF and BORIS in region/specific regulation of epigenetic processes, the impact of DNA damage on epigenetic processes as well as links between epigenetic mechanisms and early nutrition and bystander effects.

  7. Simulation of beams or plasmas crossing at relativistic velocity

    SciTech Connect

    Vay, J.-L.

    2008-05-15

    This paper addresses the numerical issues related to the modeling of beams or plasmas crossing at relativistic velocity using the particle-in-cell method. Issues related to the use of the standard Boris particle pusher are identified and a novel pusher which circumvents them is proposed, whose effectiveness is demonstrated on single particle tests. A procedure for solving the fields is proposed, which retains electrostatic, magnetostatic, and inductive field effects in the direction of the mean velocity of the species, is fully explicit and simpler than the full Darwin approximation. Finally, results are given, from a calculation using the novel features, of an ultrarelativistic beam interacting with a background of electrons.

  8. STS-106 Crew Activities Report/Flight Day 05 Highlights

    NASA Technical Reports Server (NTRS)

    2000-01-01

    On this fifth day of the STS-106 Atlantis mission, the flight crew, Commander Terrence W. Wilcutt, Pilot Scott D. Altman, and Mission Specialists Daniel C. Burbank, Edward T. Lu, Richard A. Mastracchio, Yuri Ivanovich Malenchenko, and Boris V. Morukov are seen participating in several activities. Malenchenko and Wilcutt are seen opening the hatches of the Zvezda Service Module and the Zarya Control Module, and finally, the transfer chamber of Zvezda, Progress. Burbank and Mastracchio are seen transferring food and equipment, and removing the manual docking system of Zarya. Lu, Burbank and Malenchenko are also seen checking the hatch interfaces. Footage also shows the entire interior of the International Space Station (ISS) complex.

  9. Note on online books and articles about the history of dissociation.

    PubMed

    Alvarado, Carlos S

    2008-01-01

    Students of the history of dissociation will be interested in the materials on the subject available in the digital document database Google Book Search. This includes a variety of books and journals covering automatic writing, hypnosis, mediumship, multiple personality, trance, somnambulism, and other topics. Among the authors represented in the database are: Eugène Azam, Alfred Binet, James Braid, Jean-Martin Charcot, Pierre Janet, Frederic W.H. Myers, Morton Prince, and Boris Sidis, among others. The database includes examples of case reports, conceptual discussions, and psychiatric and psychological textbook literature. PMID:19042312

  10. Prospects for Ukrainian denuclearization after the Moscow trilateral statement

    SciTech Connect

    1994-03-01

    On January 14, at the Moscow summit, Presidents Bill Clinton, Boris Yeltsin of Russia and Leonid Kravchuk of Ukraine issued a trilateral statement that again commits Ukraine to denuclearize in compliance with START I and the Lisbon Protocol and to join the nuclear Non-Proliferation Treaty (NPT) as a non-nuclear-weapon state. Recognizing that scant media attention had been paid to the importance of the trilateral statement, the Arms Control Association (ACA) held a news conference on January 28 to provide background and context on the many issues that affect prospects for Ukrainian denuclearization.

  11. Less reality, more security

    NASA Astrophysics Data System (ADS)

    Ekert, Artur

    2009-09-01

    On 25 March 1935 John Tate, the then editor of Physical Review, received a paper that Einstein had co-authored with Boris Podolsky and Nathan Rosen, his younger colleagues at Princeton. The logbooks of Physical Review show that the EPR paper, as it has since become known, bypassed the refereeing process and went straight to press. Four printed pages of beautifully constructed argument appeared in the 15 May issue. They were heralded by a brief article in the New York Times titled "Einstein attacks quantum theory". And so he did.

  12. BOREAS Regional Soils Data in Raster Format and AEAC Projection

    NASA Technical Reports Server (NTRS)

    Monette, Bryan; Knapp, David; Hall, Forrest G. (Editor); Nickeson, Jaime (Editor)

    2000-01-01

    This data set was gridded by BOREAS Information System (BORIS) Staff from a vector data set received from the Canadian Soil Information System (CanSIS). The original data came in two parts that covered Saskatchewan and Manitoba. The data were gridded and merged into one data set of 84 files covering the BOREAS region. The data were gridded into the AEAC projection. Because the mapping of the two provinces was done separately in the original vector data, there may be discontinuities in some of the soil layers because of different interpretations of certain soil properties. The data are stored in binary, image format files.

  13. Verification of nonlinear particle simulation of radio frequency waves in tokamak

    SciTech Connect

    Kuley, A. Lin, Z.; Bao, J.; Wei, X. S.; Xiao, Y.; Zhang, W.; Sun, G. Y.; Fisch, N. J.

    2015-10-15

    Nonlinear simulation model for radio frequency waves in fusion plasmas has been developed and verified using fully kinetic ion and drift kinetic electron. Ion cyclotron motion in the toroidal geometry is implemented using Boris push in the Boozer coordinates. Linear dispersion relation and nonlinear particle trapping are verified for the lower hybrid wave and ion Bernstein wave (IBW). Parametric decay instability is observed where a large amplitude pump wave decays into an IBW sideband and an ion cyclotron quasimode (ICQM). The ICQM induces an ion perpendicular heating, with a heating rate proportional to the pump wave intensity.

  14. Splitting methods for time integration of trajectories in combined electric and magnetic fields.

    PubMed

    Knapp, Christian; Kendl, Alexander; Koskela, Antti; Ostermann, Alexander

    2015-12-01

    The equations of motion of a single particle subject to an arbitrary electric and a static magnetic field form a Poisson system. We present a second-order time integration method which preserves well the Poisson structure and compare it to commonly used algorithms, such as the Boris scheme. All the methods are represented in a general framework of splitting methods. We use the so-called ϕ functions, which give efficient ways for both analyzing and implementing the algorithms. Numerical experiments show an excellent long term stability for the method considered. PMID:26764856

  15. Desert Research Institute cloud droplet videometer measurements in support of MASTEX

    SciTech Connect

    1995-02-13

    In support of the Monterey Area Ship-Track Experiment (MASTEX) the Desert Research Institute completed modifications to an existing cloud droplet videometer and construction of a second unit for deployment on board the RV Glorita during the month of June 1994. Dr. Randolph Borys accompanied the instrumentation during the period the ship was at sea and assisted in the day-to-day experiments which were conducted on board. Unusually clear conditions and high winds contributed to the lack of opportunities to deploy the new instrument from the ship.

  16. Hunting for seamounts using neural networks: learning algorithms for geomorphic studies

    NASA Astrophysics Data System (ADS)

    Valentine, A. P.; Kalnins, L. M.; Trampert, J.

    2012-04-01

    Many geophysical studies rely on finding and analysing particular topographic features: the various landforms associated with glaciation, for example, or those that characterise regional tectonics. Typically, these can readily be identified from visual inspection of datasets, but this is a tedious and time-consuming process. However, the development of techniques to perform this assessment automatically is often difficult, since a mathematical description of the feature of interest is required. To identify characteristics of a feature, such as its spatial extent, each characteristic must also have a mathematical description. Where features exhibit significant natural variations, or where their signature in data is marred by noise, performance of conventional algorithms may be poor. One potential avenue lies in the use of neural networks, or other learning algorithms, ideal for complex pattern recognition tasks. Rather than formulating a description of the feature, the user simply provides the algorithm with a training set of hand-classified examples: the problem then becomes one of assessing whether some new example shares the characteristics of this training data. In seismology, this approach is being developed for the identification of high-quality seismic waveforms amidst noisy datasets (e.g. Valentine & Woodhouse, 2010; Valentine & Trampert, in review): can it also be applied to topographic data? To explore this, we attempt to identify the locations of seamounts from gridded bathymetric data (e.g. Smith & Sandwell, 1997). Our approach involves assessing small 'patches' of ocean floor to determine whether they might plausibly contain a seamount, and if so, its location. Since seamounts have been extensively studied, this problem provides an ideal testing ground: in particular, various catalogues exist, compiled using 'traditional' approaches (e.g. Kim & Wessel, 2011). This allows us to straightforwardly generate training datasets, and compare algorithmic

  17. Differences in habitat use by blanding's turtles, Emydoidea blandingii, and painted turtles, Chysemys picta, in the Nebraska sandhills

    USGS Publications Warehouse

    Bury, R. Bruce; Germano, David J.

    2003-01-01

    We sampled a variety of wetlands in the Nebraska sandhills at Valentine National Wildlife Refuge. Significantly more individuals of painted turtles (Chrysemys picta) occurred in lakes and open waters than in marshes or small ponds, and the opposite was true for Blanding's turtles (Emydoidea blandingii). Besides this marked difference in habitat use, 46% of the captured E. blandingii in pond/marsh habitat were juveniles, but only 31.6% in lakes and open water. Current information suggests that marshes and small ponds are important habitat for juvenile turtles, especially Emydoidea blandingii.

  18. Solving constrained minimum-time robot problems using the sequential gradient restoration algorithm

    NASA Technical Reports Server (NTRS)

    Lee, Allan Y.

    1991-01-01

    Three constrained minimum-time control problems of a two-link manipulator are solved using the Sequential Gradient and Restoration Algorithm (SGRA). The inequality constraints considered are reduced via Valentine-type transformations to nondifferential path equality constraints. The SGRA is then used to solve these transformed problems with equality constraints. The results obtained indicate that at least one of the two controls is at its limits at any instant in time. The remaining control then adjusts itself so that none of the system constraints is violated. Hence, the minimum-time control is either a pure bang-bang control or a combined bang-bang/singular control.

  19. ["A shot at the father: a student's assault". Sigmund Freud and the case of Ernst Haberl].

    PubMed

    Aichhorn, Thomas

    2014-01-01

    In the fall of 1922, the Freud family was involved in a criminal case: The son of Mathilde Freud's nursing sister, Ernst Haberl, had shot at his father. With the help of August Aichhorn the Viennese Juvenile Court's social assistance department was engaged on behalf of the young man. Freud commissioned the lawyer Valentin Teirich to defend him in court. The Viennese dailies reported the deed and the trial extensively (Haberl was acquitted). That a comment published in the Neue Freie Presse was written by Freud himself, as Teirich believed, is, according to Anna Freud, highly improbable. PMID:24988808

  20. At what depths do magma-water eruptions breach the surface?

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-09-01

    When magma ascends upward in the Earth's crust, it can react violently with groundwater, leading to underground explosions or even full-fledged eruptions. If they breach the surface, these phreatomagmatic eruptions leave debris that falls concentrically around the crater or cone. Previously, researchers have sought to determine the depth within the vent from which the eruption originated by looking at the types of ejected rocks and their original positions beneath the volcanoes, but Valentine et al. found that these two factors are not necessarily directly related.

  1. Skin and soft tissue infections in the military.

    PubMed

    Lamb, Lucy; Morgan, M

    2013-09-01

    Skin and soft tissue infections (SSTI) are common in military populations regularly living and training in close contact with each other. The majority of such infections are simple and can be easily treated with antibiotics and appropriate infection control practices. Some, however, can progress to become complex and even life threatening, such as Panton-Valentine Leukocidin (PVL)-associated staphylococcus aureus pneumonia, or Streptococcus pyogenes necrotising fasciitis, which carry a mortality rate of up to 65% and 30%, respectively. This review focuses on the most important SSTIs and those more commonly affecting military personnel with advice on how they are best managed. PMID:24109144

  2. Mineral Resource of the Month: Antimony

    USGS Publications Warehouse

    Guberman, David E.

    2015-01-01

    Antimony is a lustrous silvery-white semimetal or metalloid. Archaeological and historical studies indicate that antimony and its mineral sulfides have been used by humans for at least six millennia. The alchemist Basil Valentine is sometimes credited with “discovering” the element; he described the extraction of metallic antimony from stibnite in his treatise “The Triumphal Chariot of Antimony,” published sometime between 1350 and 1600. In the early 18th century, Jöns Jakob Berzelius chose the periodic symbol for antimony (Sb) based on stibium, which is the Latin name for stibnite.

  3. Study of comets at wavelengths between 0.5 and 18 microns

    NASA Technical Reports Server (NTRS)

    Net, E. P.; Gehrz, R. D.

    1986-01-01

    Since 1969 every bright comet was measured which has reached a distance of one astronomical unit from the sun. Observing techniques were developed which make it possible to observe as close as elongation 3 deg., and to find, track and measure comets at all wavelengths in full daylight. Comet Halley was measured on twenty four occasions between December 12, 1985 and March 25, 1986. Clear weather seems to come on holidays, and days on which are observed including Winter Solstice, Christmas, New Years, Valentines day, Super Bowl Sunday and the Vernal Equinox. Halley is observed within hours of perihelion passage.

  4. Three Licentiates of the Royal College of Surgeons of Edinburgh who were decorated with the Victoria Cross.

    PubMed

    Kaufman, M H

    2011-08-01

    Since the Victoria Cross was introduced in January 1856 by Queen Victoria to reward acts of valour in the face of the enemy, initially during the Crimean War, over 1350 medals have been awarded. Of these, three were awarded to medical officers who had previously gained the Licentiate Diploma of the Royal College of Surgeons of Edinburgh (LRCS Edin) - Valentine Munbee McMaster on 25 September 1857, Henry Thomas Sylvester on 20 November 1857 (although the acts of valour for which he was awarded his VC occurred on two occasions in September 1855) and Campbell Mellis (or Millis) Douglas on 7 May 1867. PMID:21810849

  5. Nonketotic hyperglycinemia: novel mutation in the aminomethyl transferase gene. Case report.

    PubMed

    Gencpinar, Pinar; Çavuşoğlu, Dilek; Özbeyler, Ömer; Kaya, Özge Ö; Baydan, Figen; Olgac Dundar, Nihal

    2016-06-01

    Panton-Valentine leukocidin (PVL) is an exotoxin that is produced by many strains of Staphylococcus aureus, and an important virulence factor. A PVL-positive S. aureus infection leads to rapid and severe infections of soft tissue and necrotizing pneumonia in healthy adolescents, and has a high mortality. This case report included a 12-year-old male patient who admitted for fever, respiratory distress and hip pain and was identified with necrotizing pneumonia with septic pulmonary embolism, psoas abscess, cellulitis and osteomyelitis. The PVL positive methicillin-sensitive S. aureus (MSSA) was isolated in the patient blood culture. PMID:27164344

  6. PREFACE: Physics and Mathematics of Nonlinear Phenomena 2013 (PMNP2013)

    NASA Astrophysics Data System (ADS)

    Konopelchenko, B. G.; Landolfi, G.; Martina, L.; Vitolo, R.

    2014-03-01

    Modern theory of nonlinear integrable equations is nowdays an important and effective tool of study for numerous nonlinear phenomena in various branches of physics from hydrodynamics and optics to quantum filed theory and gravity. It includes the study of nonlinear partial differential and discrete equations, regular and singular behaviour of their solutions, Hamitonian and bi- Hamitonian structures, their symmetries, associated deformations of algebraic and geometrical structures with applications to various models in physics and mathematics. The PMNP 2013 conference focused on recent advances and developments in Continuous and discrete, classical and quantum integrable systems Hamiltonian, critical and geometric structures of nonlinear integrable equations Integrable systems in quantum field theory and matrix models Models of nonlinear phenomena in physics Applications of nonlinear integrable systems in physics The Scientific Committee of the conference was formed by Francesco Calogero (University of Rome `La Sapienza', Italy) Boris A Dubrovin (SISSA, Italy) Yuji Kodama (Ohio State University, USA) Franco Magri (University of Milan `Bicocca', Italy) Vladimir E Zakharov (University of Arizona, USA, and Landau Institute for Theoretical Physics, Russia) The Organizing Committee: Boris G Konopelchenko, Giulio Landolfi, Luigi Martina, Department of Mathematics and Physics `E De Giorgi' and the Istituto Nazionale di Fisica Nucleare, and Raffaele Vitolo, Department of Mathematics and Physics `E De Giorgi'. A list of sponsors, speakers, talks, participants and the conference photograph are given in the PDF. Conference photograph

  7. STS-101 crew take part in CEIT at SPACEHAB

    NASA Technical Reports Server (NTRS)

    1999-01-01

    During a Crew Equipment Interface Test (CEIT) at SPACEHAB, in Cape Canaveral, Fla., members of the STS-101 crew learn about some of the cargo that will be on their mission. At left are Mission Specialists Jeffrey N. Williams and Edward Tsang Lu (Ph.D.); at right are Commander James Donald Halsell Jr., and Mission Specialist Boris W. Morukov, who is with the Russian Space Agency (RSA). Other crew members are Pilot Scott Horowitz, and Mission Specialists Mary Ellen Weber, (Ph.D.) and Boris W. Morukov and Yuri Malenchenko, who are with the Russian Space Agency. The primary objective of the STS-101 mission is to complete the initial outfitting of the International Space Station, making it fully ready for the first long-term crew. The seven-member crew will transfer almost two tons of equipment and supplies from SPACEHAB's Logistics Double Module. Additionally, they will unpack a shipment of supplies delivered earlier by a Russian Progress space tug and begin outfitting the newly arrived Zvezda Service Module. Three astronauts will perform two space walks to transfer and install parts of the Russian Strela cargo boom that are attached to SPACEHAB's Integrated Cargo Container, connect utility cables between Zarya and Zvezda, and install a magnetometer/pole assembly on the Service Module. Additional activities for the STS-101 astronauts include working with the Space Experiment Module (SEM-06) and the Mission to America's Remarkable Schools (MARS), two educational initiatives. STS-101 is scheduled for launch no earlier than March 16, 2000.

  8. EDITORIAL: Optical orientation Optical orientation

    NASA Astrophysics Data System (ADS)

    SAME ADDRESS *, Yuri; Landwehr, Gottfried

    2008-11-01

    Boris Petrovitch Zakharchenya (1928-2005) This issue is dedicated to the memory of Boris Petrovich Zakharchenya, who died at the age of 77 in April 2005. He was an eminent scientist and a remarkable man. After studying physics at Leningrad University he joined the Physico-Technical Institute (now the A F Ioffe Institute) in 1952 and became the co-worker of Evgeny Feodorovich Gross, shortly after the exciton was discovered in his laboratory. The experiments on cuprous oxide crystals in the visible spectral range showed a hydrogen-like spectrum, which was interpreted as excitonic absorption. The concept of the exciton had been conceived some years earlier by Jacov Frenkel at the Physico-Technical Institute. Immediately after joining Gross, Zakharchenya succeeded in producing spectra of unprecedented quality. Subsequently the heavy and the light hole series were found. Also, Landau splitting was discovered when a magnetic field was applied. The interpretation of the discovery was thrown into doubt by Russian colleagues and it took some time, before the correct interpretation prevailed. Shortly before his death, Boris wrote the history of the discovery of the exciton, which has recently been published in Russian in a book celebrating the 80th anniversary of his birth [1]. The book also contains essays by Boris on various themes, not only on physics, but also on literature. Boris was a man of unusually wide interests, he was not only fascinated by physics, but also loved literature, art and music. This can be seen in the first article of this issue The Play of Light in Crystals which is an abbreviated version of his more complete history of the discovery of the exciton. It also gives a good impression of the personality of Boris. One of us (GL) had the privilege to become closely acquainted with him, while he was a guest professor at the University of Würzburg. During that time we had many discussions, and I recall his continuing rage on the wrong attribution of the

  9. EDITORIAL: Optical orientation Optical orientation

    NASA Astrophysics Data System (ADS)

    SAME ADDRESS *, Yuri; Landwehr, Gottfried

    2008-11-01

    Boris Petrovitch Zakharchenya (1928-2005) This issue is dedicated to the memory of Boris Petrovich Zakharchenya, who died at the age of 77 in April 2005. He was an eminent scientist and a remarkable man. After studying physics at Leningrad University he joined the Physico-Technical Institute (now the A F Ioffe Institute) in 1952 and became the co-worker of Evgeny Feodorovich Gross, shortly after the exciton was discovered in his laboratory. The experiments on cuprous oxide crystals in the visible spectral range showed a hydrogen-like spectrum, which was interpreted as excitonic absorption. The concept of the exciton had been conceived some years earlier by Jacov Frenkel at the Physico-Technical Institute. Immediately after joining Gross, Zakharchenya succeeded in producing spectra of unprecedented quality. Subsequently the heavy and the light hole series were found. Also, Landau splitting was discovered when a magnetic field was applied. The interpretation of the discovery was thrown into doubt by Russian colleagues and it took some time, before the correct interpretation prevailed. Shortly before his death, Boris wrote the history of the discovery of the exciton, which has recently been published in Russian in a book celebrating the 80th anniversary of his birth [1]. The book also contains essays by Boris on various themes, not only on physics, but also on literature. Boris was a man of unusually wide interests, he was not only fascinated by physics, but also loved literature, art and music. This can be seen in the first article of this issue The Play of Light in Crystals which is an abbreviated version of his more complete history of the discovery of the exciton. It also gives a good impression of the personality of Boris. One of us (GL) had the privilege to become closely acquainted with him, while he was a guest professor at the University of Würzburg. During that time we had many discussions, and I recall his continuing rage on the wrong attribution of the

  10. Fly ash as a liming material for corn production

    SciTech Connect

    Tarkalson, D.D.; Hergert, G.W.; Stevens, W.B.; McCallister, D.L.; Kackman, S.D.

    2005-05-01

    Fly ash produced as a by-product of subbituminous coal combustion can potentially serve as an alternative liming material without negatively affecting corn (Zea mays L.) production in areas where use of conventional liming materials can be uneconomical due to transportation costs. A study was conducted to determine if fly ash produced from the Nebraska Public Power District Gerald Gentleman Power Station located in Sutherland, NE could be used as an alternative liming material. Combinations of dry fly ash (DFA), wet fly ash (WFA), beet lime (by-product of sugar beet (Beta vulgaris L.) processing) (BL), and agricultural lime (AGL) were applied at rates ranging from 0.43 to 1.62 times the recommended lime rate to plots on four acidic soils (Anselmo fine sandy loam, Hord fine sandy loam, Holdrege sandy loam, and Valentine fine sand). Soil samples were collected to a depth of 0.2 m from plots and analyzed for pH before lime applications and twice periodically after lime application. The Hord and Valentine soils were analyzed for exchangeable Ca, Mg, K, Na,and Al for determination of percent Al saturation on selected treatments and sampling dates. Corn grain yields were determined annually. It is concluded that the fly ash utilized in this study and applied at rates in this study, increases soil pH comparable to agricultural lime and is an appropriate alternative liming material.

  11. Social anxiety and the accuracy of predicted affect.

    PubMed

    Martin, Shannon M; Quirk, Stuart W

    2015-01-01

    Social anxiety is theorised to arise from sustained over-activation of a mammalian evolved system for detecting and responding to social threat with corresponding diminished opportunities for attaining the pleasure of safe attachments. Emotional forecasting data from two holidays were used to test the hypothesis that greater social anxiety would be associated with decreased expectations of positive affect (PA) and greater anticipated negative affect (NA) on a holiday marked by group celebration (St. Patrick's Day) while being associated with greater predicted PA for daters on a romantic holiday (Valentine's Day). Participants completed symptom reports, made affective forecasts and provided multiple affect reports throughout each holiday. Higher levels of social anxiety were associated with greater anticipated PA for Valentine's Day daters, but lower experienced PA on the holiday; this was not found for trait anxiety and depression. Alternatively, trait anxiety, depression and social anxiety were associated with less predicted PA for St. Patrick's Day, greater anticipated NA and diminished experienced PA/greater NA during the holiday. Results are discussed in light of perceived hope for rewarding safe emotional contact for those daters in contrast to the greater possibility for social threat associated with group celebration typical of St. Patrick's Day. PMID:24611591

  12. Generating geomorphological catalogues using neural networks: Seamounts in the Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Valentine, Andrew; Kalnins, Lara; van Dinther, Chantal; Trampert, Jeannot

    2013-04-01

    We recently introduced the idea that neural networks may be used to construct catalogues of geomorphological features, by extrapolating from the characteristics of a set of hand-selected examples (Valentine et al., 2012). These learning algorithms are inspired by the complex pattern identification and recognition capabilities of the human brain and remove the need to develop an a priori model of the feature of interest. In order to demonstrate this approach, and to develop a clearer understanding of its possibilities and pitfalls, we concentrate on the problem of identifying seamounts - isolated topographic highs of volcanic origin - in the world's oceans. The distribution of seamounts in time and space can provide important constraints on the tectonic history and evolution of the Earth and has been studied using several conventional approaches (e.g. Kim & Wessel, 2011). However, these typically perform poorly in the Atlantic, where the slow spreading rate results in a rough 'background' seafloor that produces many false positives. The learning algorithm approach should improve this, as it attempts to encapsulate more complex information about the seamount and its surroundings. We present an overview of our work to date, with a focus on results from a systematic search for seamounts in the Atlantic. We compare the performance of our approach in detecting seamounts in bathymetric, free-air gravity anomaly and vertical gravity gradient (VGG) datasets to examine the particular strengths and weaknesses of each data type and to assess the potential benefits of assimilating information from two or three data types simultaneously. We compare the resulting seamount database with existing catalogues, examining the variations in measures such as total count, height distribution, and spatial and temporal distribution across the Atlantic, and comment on the potential implications for our understanding of the tectonic history of the region. Kim, S.-S. & Wessel, P., 2011. New

  13. Contributions to the History of Astronomy, Vol. 9; (German Title: Beiträge zur Astronomiegeschichte, Band 9)

    NASA Astrophysics Data System (ADS)

    Dick, Wolfgang R.; Duerbeck, H. W.; Hamel, Jürgen

    The contributions deal with astronomical events of the past 1000 years. We elucidate the person of the single European observer of the supernova of 1006, and the views of Christoph Scheiner and Otto von Guericke on the structure and substance of the cosmos. A study of the development of the Copernican and the cosmological principles conclude this group of themes. Biographical investigations were carried out on the clockmaker Nikolaus Lilienfeld, the astronomers Johann Wurzelbau, Friedrich Wilhelm Toennies and Boris Karpov as well as the “panbabylonist” Alfred Jeremias. Astronomers can be active also in poetry and fiction. This is shown in the studies of Johann Leonard Rost and Friedrich Wilhelm Bessel. Finally, Johannes Hevelius' Observatory in Danzig/Gdansk, destroyed by a fire in 1679, is reconstructed by means of printed sources, old maps and photographs. The book concludes by short communications, obituaries and book reviews.

  14. Method to integrate full particle orbit in toroidal plasmas

    NASA Astrophysics Data System (ADS)

    Wei, X. S.; Xiao, Y.; Kuley, A.; Lin, Z.

    2015-09-01

    It is important to integrate full particle orbit accurately when studying charged particle dynamics in electromagnetic waves with frequency higher than cyclotron frequency. We have derived a form of the Boris scheme using magnetic coordinates, which can be used effectively to integrate the cyclotron orbit in toroidal geometry over a long period of time. The new method has been verified by a full particle orbit simulation in toroidal geometry without high frequency waves. The full particle orbit calculation recovers guiding center banana orbit. This method has better numeric properties than the conventional Runge-Kutta method for conserving particle energy and magnetic moment. The toroidal precession frequency is found to match that from guiding center simulation. Many other important phenomena in the presence of an electric field, such as E × B drift, Ware pinch effect and neoclassical polarization drift are also verified by the full orbit simulation.

  15. Complex and liquid hydrides for energy storage

    NASA Astrophysics Data System (ADS)

    Callini, Elsa; Atakli, Zuleyha Özlem Kocabas; Hauback, Bjørn C.; Orimo, Shin-ichi; Jensen, Craig; Dornheim, Martin; Grant, David; Cho, Young Whan; Chen, Ping; Hjörvarsson, Bjørgvin; de Jongh, Petra; Weidenthaler, Claudia; Baricco, Marcello; Paskevicius, Mark; Jensen, Torben R.; Bowden, Mark E.; Autrey, Thomas S.; Züttel, Andreas

    2016-04-01

    The research on complex hydrides for hydrogen storage was initiated by the discovery of Ti as a hydrogen sorption catalyst in NaAlH4 by Boris Bogdanovic in 1996. A large number of new complex hydride materials in various forms and combinations have been synthesized and characterized, and the knowledge regarding the properties of complex hydrides and the synthesis methods has grown enormously since then. A significant portion of the research groups active in the field of complex hydrides is collaborators in the International Energy Agreement Task 32. This paper reports about the important issues in the field of complex hydride research, i.e. the synthesis of borohydrides, the thermodynamics of complex hydrides, the effects of size and confinement, the hydrogen sorption mechanism and the complex hydride composites as well as the properties of liquid complex hydrides. This paper is the result of the collaboration of several groups and is an excellent summary of the recent achievements.

  16. Numerical error in electron orbits with large. omega. sub ce. delta. t

    SciTech Connect

    Parker, S.E.; Birdsall, C.K.

    1989-12-20

    We have found that running electrostatic particle codes relatively large {omega}{sub ce}{Delta}t in some circumstances does not significantly affect the physical results. We first present results from a single particle mover finding the correct first order drifts for large {omega}{sub ce}{Delta}t. We then characterize the numerical orbit of the Boris algorithm for rotation when {omega}{sub ce}{Delta}t {much gt} 1. Next, an analysis of the guiding center motion is given showing why the first order drift is retained at large {omega}{sub ce}{Delta}t. Lastly, we present a plasma simulation of a one dimensional cross field sheath, with large and small {omega}{sub ce}{Delta}t, with very little difference in the results. 15 refs., 7 figs., 1 tab.

  17. Development and Test of 2.5-Dimensional Electromagnetic PIC Simulation Code

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Yun; Lee, Ensang; Kim, Khan-Hyuk; Seon, Jongho; Lee, Dong-Hun; Ryu, Kwang-Sun

    2015-03-01

    We have developed a 2.5-dimensional electromagnetic particle simulation code using the particle-in-cell (PIC) method to investigate electromagnetic phenomena that occur in space plasmas. Our code is based on the leap-frog method and the centered difference method for integration and differentiation of the governing equations. We adopted the relativistic Buneman-Boris method to solve the Lorentz force equation and the Esirkepov method to calculate the current density while maintaining charge conservation. Using the developed code, we performed test simulations for electron two-stream instability and electron temperature anisotropy induced instability with the same initial parameters as used in previously reported studies. The test simulation results are almost identical with those of the previous papers.

  18. Specificity and robustness in transcription control networks.

    PubMed

    Sengupta, Anirvan M; Djordjevic, Marko; Shraiman, Boris I

    2002-02-19

    Recognition by transcription factors of the regulatory DNA elements upstream of genes is the fundamental step in controlling gene expression. How does the necessity to provide stability with respect to mutation constrain the organization of transcription control networks? We examine the mutation load of a transcription factor interacting with a set of n regulatory response elements as a function of the factor/DNA binding specificity and conclude on theoretical grounds that the optimal specificity decreases with n. The predicted correlation between variability of binding sites (for a given transcription factor) and their number is supported by the genomic data for Escherichia coli. The analysis of E. coli genomic data was carried out using an algorithm suggested by the biophysical model of transcription factor/DNA binding. Complete results of the search for candidate transcription factor binding sites are available at http://www.physics.rockefeller.edu/~boris/public/search_ecoli. PMID:11854503

  19. Postmiocene geodynamic evolution of the drake passage, Western Antarctic Region, southern ocean

    NASA Astrophysics Data System (ADS)

    Teterin, D. E.

    2011-08-01

    In 1994-2006, the German research vessel, Polarstern, and the Russian research vessel, Akademik Boris Petrov, carried out marine geologic and geophysical explorations in the Western Antarctic Region within the Bellingshausen, Amundsen, and Scotia marginal Seas and the Drake Passage. In these expeditions, new unique data on submarine topography have been collected by a multibeam echosounder, gravity and magnetic measurements have been carried out, multichannel seismic profiling has been performed, and the collections of rock samples have been acquired. The analysis and interpretation of new evidence together with previous geologic and geophysical data for the Drake Passage region have shown that end of spreading in the Aluk Ridge three million years ago resulted in the redistribution of stresses associated with the relative motion of the Antarctic, Scotia, and Phoenix Plates, which, in turn, caused significant tectonic reconstruction of the entire transition zone of the Drake Passage.

  20. Nonlinear particle simulation of ion cyclotron waves in toroidal geometry

    SciTech Connect

    Kuley, A. Lin, Z.; Bao, J.; Wei, X. S.; Xiao, Y.

    2015-12-10

    Global particle simulation model has been developed in this work to provide a first-principles tool for studying the nonlinear interactions of radio frequency (RF) waves with plasmas in tokamak. In this model, ions are considered as fully kinetic particles using the Vlasov equation and electrons are treated as guiding centers using the drift kinetic equation with realistic electron-to-ion mass ratio. Boris push scheme for the ion motion has been developed in the toroidal geometry using magnetic coordinates and successfully verified for the ion cyclotron and ion Bernstein waves in global gyrokinetic toroidal code (GTC). The nonlinear simulation capability is applied to study the parametric decay instability of a pump wave into an ion Bernstein wave side band and a low frequency ion cyclotron quasi mode.

  1. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    At the 217-foot level of the Rotating Service Structure on Launch Pad 39B, the STS-106 crew takes a break during Terminal Countdown Demonstration Activities (TCDT) for a group photo. Pictured from left are Mission Specialists Richard A. Mastracchio, Yuri I. Malenchenko and Daniel C. Burbank; Pilot Scott D. Altman; Commander Terrence W. Wilcutt; and Mission Specialists Boris V. Morukov and Edward T. Lu. The TCDT provides the crew with emergency egress training, opportunities to inspect their mission payload in the orbiter'''s payload bay, and a simulated launch countdown. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven- member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  2. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Strapped into their seats inside the orbiter Atlantis for a simulated countdown exercise are (left to right) STS-106 Mission Specialists Boris V. Morukov, Yuri I. Malenchenko and Daniel C. Burbank. The simulation is part of Terminal Countdown Demonstration Test (TCDT) activities. The TCDT also provides the crew with emergency egress training and opportunities to inspect their mission payload in the orbiter'''s payload bay. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  3. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    At the 195-foot level of Launch Pad 39B, STS-106 Mission Specialists (left to right) Boris V. Morukov, Daniel C. Burbank and Yuri I. Malenchenko pause for a photo before taking their seats in the slidewire basket, which is part of the emergency egress equipment. They and the rest of the STS-106 crew are taking part in Terminal Countdown Demonstration Activities (TCDT), which includes emergency egress training, along with opportunities to inspect their mission payload in the orbiter'''s payload bay, and a simulated launch countdown. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  4. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    At Launch Pad 39B, STS-106 Mission Specialists Yuri I. Malenchenko, Daniel C. Burbank and Boris V. Morukov speedily head for the slidewire baskets that are used for emergency egress from the orbiter. The three are taking part in Terminal Countdown Demonstration Activities (TCDT), along with the rest of the STS- 106 crew. The TCDT also provides the crew with opportunities to inspect their mission payload in the orbiter'''s payload bay, and a simulated launch countdown. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  5. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    At the 195-foot level of Launch Pad 39B, STS-106 Mission Specialists (left to right) Boris V. Morukov, Daniel C. Burbank and Yuri I. Malenchenko take their seats in the slidewire basket, which is part of the emergency egress equipment. They and the rest of the STS-106 crew are taking part in Terminal Countdown Demonstration Activities (TCDT), which includes emergency egress training, along with opportunities to inspect their mission payload in the orbiter'''s payload bay, and a simulated launch countdown. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven- member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  6. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    STS-106 Mission Specialists stand in a slide wire basket at the foot of Launch Pad 39-B. Pictured from left are Daniel C. Burbank, Boris V. Morukov and Yuri I. Malenchenko. Malenchenko and Morukov are with the Russian Aviation and Space Agency. The flight crew were at Kennedy Space Center to take part in Terminal Countdown Demonstration Test (TCDT) activities. The TCDT provides the crew with emergency egress training and opportunities to inspect their mission payload in the orbiter'''s payload bay. STS- 106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  7. Spectral properties and chiral symmetry violations of (staggered) domain wall fermions in the Schwinger model

    NASA Astrophysics Data System (ADS)

    Hoelbling, Christian; Zielinski, Christian

    2016-07-01

    We follow up on a suggestion by Adams and construct explicit domain wall fermion operators with staggered kernels. We compare different domain wall formulations, namely the standard construction as well as Boriçi's modified and Chiu's optimal construction, utilizing both Wilson and staggered kernels. In the process, we generalize the staggered kernels to arbitrary even dimensions and introduce both truncated and optimal staggered domain wall fermions. Some numerical investigations are carried out in the (1 +1 )-dimensional setting of the Schwinger model, where we explore spectral properties of the bulk, effective and overlap Dirac operators in the free-field case, on quenched thermalized gauge configurations and on smooth topological configurations. We compare different formulations using the effective mass, deviations from normality and violations of the Ginsparg-Wilson relation as measures of chirality.

  8. Structure and phycobiliprotein composition of phycobilisomes from Griffithsia pacifica (Rhodophyceae)

    SciTech Connect

    Gantt, E.; Lipschultz, C.A.

    1980-09-01

    Phycobilisomes in Griffithsia pacifica are closely spaced on the thylakoid membrane. By negative staining, attached and isolated phycobilisomes have been shown to have a block shaped appearance. They are 63 nm long, 38 nm high, and 38 nm wide, making them the largest thus far reported. Isolated phycobilisomes, shown to be functionally intact by their 675 nm fluorescence emission (excitation 545 nm) were stable for more than a day. Phycobiliproteins from dissociated phycobilisomes, separated on sucrose gradients and by polyacrylamide, electrophoresis, yielded large (R-) and small (r-) molecular weight species of phycoerythrin (ca. 4:1 respectively) constituting 89% of the phycobiliprotein content, with R-phycocyanin 8%, and allophycocyanin 3% accounting for the rest. Phycobilisomes of Griffithsia pacifica and Porphyridium purpureum (Bory) Drew and Ross (P. cruentum) are structurally very similar with phycoerythrin being on the outside and surrounding a core of R-phycocyanin and allophycocyanin.

  9. Ethical considerations in psychiatric profiling of political figures.

    PubMed

    Post, Jerrold M

    2002-09-01

    Questions concerning such matters as the effects of health and alcoholism on Boris Yeltsin's decision making; the mind of the Unabomber; the psychology and decision making of Saddam Hussein of Iraq, who was initially characterized by the US Government as "the madman of the Middle East"; the psychology of David Koresh and the Branch Davidians, who were involved in an extended siege with the Bureau of Alcohol, Tobacco, and Firearms and the Federal Bureau of Investigation that ended tragically on April 19, 1993; and, most recently, the psychology of the nineteen al-Qaeda terrorists responsible for the tragic events of September 11, 2001 in which they claimed thousands of lives while giving their own, "killing in the name of God," and of their charismatic leader Osama bin Laden have led journalists to turn to social scientists, including psychiatrists, to offer commentary on public figures. PMID:12232976

  10. BOREAS Forest Cover Data Layers of the NSA in Raster Format

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Knapp, David; Tuinhoff, Manning

    2000-01-01

    This data set was processed by BORIS staff from the original vector data of species, crown closure, cutting class, and site classification/subtype into raster files. The original polygon data were received from Linnet Graphics, the distributor of data for MNR. In the case of the species layer, the percentages of species composition were removed. This reduced the amount of information contained in the species layer of the gridded product, but it was necessary in order to make the gridded product easier to use. The original maps were produced from 1:15,840-scale aerial photography collected in 1988 over an area of the BOREAS NSA MSA. The data are stored in binary, image format files and they are available from Oak Ridge National Laboratory. The data files are available on a CD-ROM (see document number 20010000884).

  11. Recognizing the obvious bush should declare the ABM Treaty dead

    SciTech Connect

    1992-02-05

    In televised speech to the Russian people on January 29, Russia`s President Boris Yeltsin called for the United States and Russia to create and jointly operate a global defense system. One day earlier, in his State of the Union address, George Bush affirmed his own commitment to strategic defense, or SDI. Washington and Moscow now both are on record in favor of deploying defenses against missile attacks. Then late last week, Yeltsin at the United Nations reaffirmed his Moscow statement. The common Bush-Yeltsin view is not surprising. Both of their countries face a growing danger of accidental, unauthorized, or irrational attacks from an expanding number of states armed with ballistic missiles.

  12. Recent developments in neutrino physics

    SciTech Connect

    Garvey, G.T.

    1991-01-01

    I shall attempt to summarize recent developments in the experimental situation in neutrino physics. The paper will deal with recent results, drawing on either published work or research that has been presented in preprint form, as there is an adequate supply of interesting and controversial data restricting oneself to these generally more reliable sources. The discussion of the theoretical implication of these experimental results will be presented in the following paper by Boris Kayser. The topics to be covered in this presentation are: direct measurements of {bar {nu}}{sub e} mass via beta endpoint studies; status of solar neutrino observations; status of 17-keV neutrino'' reports; and the use of {nu}p elastic scattering to determine the strange quark'' content of the proton. 2 refs., 15 figs., 9 tabs.

  13. STS-106 Crew Activity Report/Flight Day 1 Highlights

    NASA Technical Reports Server (NTRS)

    2000-01-01

    On this first day of the STS-106 Atlantis mission, the flight crew, Commander Terrence W. Wilcutt, Pilot Scott D. Altman, and Mission Specialists Daniel C. Burbank, Edward T. Lu, Richard A. Mastracchio, Yuri Ivanovich Malenchenko, and Boris V. Morukov are seen performing pre-launch activities. They are shown sitting around the breakfast table with the traditional cake, suiting-up, and riding out to the launch pad. The final inspection team is seen as they conduct their final check of the space shuttle on the launch complex. Also, included are various panoramic views of the shuttle on the pad. The crew is readied in the 'white room' for their mission. After the closing of the hatch and arm retraction, launch activities are shown including countdown, engine ignition, launch, and the separation of the Solid Rocket Boosters.

  14. Water relations, thallus structure and photosynthesis in Negev Desert lichens

    NASA Technical Reports Server (NTRS)

    Palmer, R. J. Jr; Friedmann, E. I.

    1990-01-01

    The role of lichen thallus structure in water relations and photosynthesis was studied in Ramalina maciformis (Del.) Bory and Teloschistes lacunosus (Rupr.) Sav. Water-vapour adsorption and photosynthesis are dependent upon thallus integrity and are significantly lower in crushed thalli. Cultured phycobiont (Trebouxia sp.) cells are capable of photosynthesis over the same relative humidity range (> 80% RH) as are intact lichens. Thus, water-vapour adsorption by the thallus and physiological adaptation of the phycobiont contribute to the ability of these lichens to photosynthesize in an arid environment. Despite differences in their anatomical structure and water-uptake characteristics, their CO2 incorporation is similar. The two lichens use liquid water differently and they occupy different niches.

  15. View of signing of ASTP joint flight readiness review

    NASA Technical Reports Server (NTRS)

    1975-01-01

    An overall view of the signing of the Apollo Soyuz Test Project (ASTP) joint flight readiness review in ceremonies on May 22, 1975 in Moscow. Academician Vladimir A. Kotelnikov (on left) and NASA Deputy Administrator George M. Low (in center) are seen affixing their signatures to the ASTP document. Kotelnikov is the Acting President of the USSR Academy of Sciences. Seated at far left is Professor Konstantin D. Bushuyev, the Soviet Technical Director of ASTP. Dr. Glynn S. Lunney, the U.S. Technical Director of ASTP, is seated on Dr. Low's left. Arnold W. Frutkin (in light jacket), NASA Administrator for International Affairs, is standing behind Dr. Low. Academician Boris N. Petrov (in dark suit), Chairman of the USSR Council for International Cooperation in the Exploration and Use of Outer Space, is standing behind Kotelnikov. The signing of the agreement took place at the Presidium of the Academy of Sciences in Moscow.

  16. STS-106 Mission Specialists Morukov and Malenchenko greeted by Halsell

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Jim Halsell Jr. (left), former mission commander and now the manager, Shuttle Program Integration Office, chats with STS-106 Mission Specialists Boris V. Morukov (center) and Yuri I. Malenchenko (right) after their arrival at KSC. Morukov and Malenchenko, who are with the Russian Aviation and Space Agency, are at KSC with the rest of the crew to take part in Terminal Countdown Demonstration Test activities, which include emergency egress training and a simulated launch countdown. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  17. BOREAS Level 3-b AVHRR-LAC Imagery: Scaled At-sensor Radiance in LGSOWG Format

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Nickeson, Jaime; Newcomer, Jeffrey A.; Cihlar, Josef

    2000-01-01

    The BOREAS Staff Science Satellite Data Acquisition Program focused on providing the research teams with the remotely sensed satellite data products they needed to compare and spatially extend point results. Data acquired from the AVHRR instrument on the NOAA-9, -11, -12, and -14 satellites were processed and archived for the BOREAS region by the MRSC and BORIS. The data were acquired by CCRS and were provided for use by BOREAS researchers. A few winter acquisitions are available, but the archive contains primarily growing season imagery. These gridded, at-sensor radiance image data cover the period of 30-Jan-1994 to 18-Sep-1996. Geographically, the data cover the entire 1,000-km x 1,000-km BOREAS region. The data are stored in binary image format files.

  18. A comparative study of computational methods in cosmic gas dynamics

    NASA Technical Reports Server (NTRS)

    Van Albada, G. D.; Van Leer, B.; Roberts, W. W., Jr.

    1982-01-01

    Many theoretical investigations of fluid flows in astrophysics require extensive numerical calculations. The selection of an appropriate computational method is, therefore, important for the astronomer who has to solve an astrophysical flow problem. The present investigation has the objective to provide an informational basis for such a selection by comparing a variety of numerical methods with the aid of a test problem. The test problem involves a simple, one-dimensional model of the gas flow in a spiral galaxy. The numerical methods considered include the beam scheme, Godunov's method (G), the second-order flux-splitting method (FS2), MacCormack's method, and the flux corrected transport methods of Boris and Book (1973). It is found that the best second-order method (FS2) outperforms the best first-order method (G) by a huge margin.

  19. STS-106 crew breakfast in O&C building before launch

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The STS-106 crew relax after breakfast and before suitup for launch. Seated (left to right) are Mission Specialists Daniel C. Burbank and Boris V. Morukov; Pilot Scott D. Altman; Commander Terrence W. Wilcutt; and Mission Specialists Edward T. Lu, Richard A. Mastracchio and Yuri I. Malenchenko. Morukov and Malenchenko are with the Russian Aviation and Space Agency. Launch of Space Shuttle Atlantis is set for 8:45 a.m. EDT on the fourth flight to the International Space Station. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbe d is due to arrive at the Station in late fall.

  20. STS-106 crew checks out payload at SPACEHAB

    NASA Technical Reports Server (NTRS)

    2000-01-01

    At SPACEHAB, Port Canaveral, Fla., members of the STS-106 crew check out part of the payload, called TVIS, on their mission to the International Space Station. From left are Mission Specialist Boris Morukov, who is with the Russian Space Agency, Pilot Scott Altman and Mission Specialist Edward Lu. TVIS is the Treadmill Vibration Isolation System, a device to collect data on how vibrations imparted by crew exercise may be reduced or eliminated on the International Space Station. Those vibrations could disturb delicate microgravity experiments on the Space Station. During the mission, the crew will complete service module support tasks on orbit, transfer supplies and outfit the Space Station for the first long-duration crew. STS-106 is scheduled to launch Sept. 8.

  1. STS-106 crew checks out payload at SPACEHAB

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Members of the STS-106 crew get information from a worker while looking over paperwork at SPACEHAB, Port Canaveral, Fla., about the payload on their mission to the International Space Station. From left (in uniform) are Pilot Scott Altman and Mission Specialists Edward Lu and Boris Morukov, who is with the Russian Space Agency. Among the payload is the Treadmill Vibration Isolation System (TVIS), a device to collect data on how vibrations imparted by crew exercise may be reduced or eliminated on the International Space Station. Those vibrations could disturb delicate microgravity experiments on the Space Station. During the mission, the crew will complete service module support tasks on orbit, transfer supplies and outfit the Space Station for the first long-duration crew. STS-106 is scheduled to launch Sept. 8.

  2. STS-106 crew checks out payload at SPACEHAB

    NASA Technical Reports Server (NTRS)

    2000-01-01

    At SPACEHAB, Port Canaveral, Fla., members of the STS-106 crew look over TVIS equipment that will be part of the payload on their mission to the International Space Station. From left are Pilot Scott Altman and Mission Specialists Edward Lu and (behind) Boris Morukov, who is with the Russian Space Agency. TVIS is the Treadmill Vibration Isolation System, a device to collect data on how vibrations imparted by crew exercise may be reduced or eliminated on the International Space Station. Those vibrations could disturb delicate microgravity experiments on the Space Station. During the mission, the crew will complete service module support tasks on orbit, transfer supplies and outfit the Space Station for the first long-duration crew. STS-106 is scheduled to launch Sept. 8.

  3. STS-106 crew checks out payload at SPACEHAB

    NASA Technical Reports Server (NTRS)

    2000-01-01

    At SPACEHAB, Port Canaveral, Fla., members of the STS-106 crew become familiar with part of the payload on their mission to the International Space Station. From left are Pilot Scott Altman and Mission Specialists Edward Lu and Boris Morukov, who is with the Russian Space Agency. Among the payload is the Treadmill Vibration Isolation System (TVIS), a device to collect data on how vibrations imparted by crew exercise may be reduced or eliminated on the International Space Station. Those vibrations could disturb delicate microgravity experiments on the Space Station. During the mission, the crew will complete service module support tasks on orbit, transfer supplies and outfit the Space Station for the first long-duration crew. STS-106 is scheduled to launch Sept. 8.

  4. STS-106 crew checks out payload at SPACEHAB

    NASA Technical Reports Server (NTRS)

    2000-01-01

    At SPACEHAB, Port Canaveral, Fla., members of the STS-106 crew look over TVIS equipment that will be part of the payload on their mission to the International Space Station. From left (in uniform) are Pilot Scott Altman and Mission Specialists Edward Lu and Boris Morukov, who is with the Russian Space Agency. TVIS is the Treadmill Vibration Isolation System, a device to collect data on how vibrations imparted by crew exercise may be reduced or eliminated on the International Space Station. Those vibrations could disturb delicate microgravity experiments on the Space Station. During the mission, the crew will complete service module support tasks on orbit, transfer supplies and outfit the Space Station for the first long-duration crew. STS-106 is scheduled to launch Sept. 8.

  5. Evolutionary Diversification of SPANX-N Sperm Protein Gene Structure and Expression

    PubMed Central

    Kouprina, Natalay; Noskov, Vladimir N.; Pavlicek, Adam; Collins, N. Keith; Schoppee Bortz, Pamela D.; Ottolenghi, Chris; Loukinov, Dmitri; Goldsmith, Paul; Risinger, John I.; Kim, Jung-Hyun; Westbrook, V. Anne; Solomon, Gregory; Sounders, Hanna; Herr, John C.; Jurka, Jerzy; Lobanenkov, Victor; Schlessinger, David; Larionov, Vladimir

    2007-01-01

    The sperm protein associated with nucleus in the X chromosome (SPANX) genes cluster at Xq27 in two subfamilies, SPANX-A/D and SPANX-N. SPANX-A/D is specific for hominoids and is fairly well characterized. The SPANX-N gave rise to SPANX-A/D in the hominoid lineage ∼7 MYA. Given the proposed role of SPANX genes in spermatogenesis, we have extended studies to SPANX-N gene evolution, variation, regulation of expression, and intra-sperm localization. By immunofluorescence analysis, SPANX-N proteins are localized in post-meiotic spermatids exclusively, like SPANX-A/D. But in contrast to SPANX-A/D, SPANX-N are found in all ejaculated spermatozoa rather than only in a subpopulation, are localized in the acrosome rather than in the nuclear envelope, and are expressed at a low level in several nongametogenic adult tissues as well as many cancers. Presence of a binding site for CTCF and its testis-specific paralogue BORIS in the SPANX promoters suggests, by analogy to MAGE-A1 and NY-ESO-1, that their activation in spermatogenesis is mediated by the programmed replacement of CTCF by BORIS. Based on the relative density of CpG, the more extended expression of SPANX-N compared to SPANX-A/D in nongametogenic tissues is likely attributed to differences in promoter methylation. Our findings suggest that the recent duplication of SPANX genes in hominoids was accompanied by different localization of SPANX-N proteins in post-meiotic sperm and additional expression in several nongonadal tissues. This suggests a corresponding functional diversification of SPANX gene families in hominoids. SPANX proteins thus provide unique targets to investigate their roles in the function of spermatozoa, selected malignancies, and for SPANX-N, in other tissues as well. PMID:17406683

  6. Research Opportunities at Storm Peak Laboratory

    NASA Astrophysics Data System (ADS)

    Hallar, A. G.; McCubbin, I. B.

    2006-12-01

    The Desert Research Institute (DRI) operates a high elevation facility, Storm Peak Laboratory (SPL), located on the west summit of Mt. Werner in the Park Range near Steamboat Springs, Colorado at an elevation of 3210 m MSL (Borys and Wetzel, 1997). SPL provides an ideal location for long-term research on the interactions of atmospheric aerosol and gas- phase chemistry with cloud and natural radiation environments. The ridge-top location produces almost daily transition from free tropospheric to boundary layer air which occurs near midday in both summer and winter seasons. Long-term observations at SPL document the role of orographically induced mixing and convection on vertical pollutant transport and dispersion. During winter, SPL is above cloud base 25% of the time, providing a unique capability for studying aerosol-cloud interactions (Borys and Wetzel, 1997). A comprehensive set of continuous aerosol measurements was initiated at SPL in 2002. SPL includes an office-type laboratory room for computer and instrumentation setup with outside air ports and cable access to the roof deck, a cold room for precipitation and cloud rime ice sample handling and ice crystal microphotography, a 150 m2 roof deck area for outside sampling equipment, a full kitchen and two bunk rooms with sleeping space for nine persons. The laboratory is currently well equipped for aerosol and cloud measurements. Particles are sampled from an insulated, 15 cm diameter manifold within approximately 1 m of its horizontal entry point through an outside wall. The 4 m high vertical section outside the building is capped with an inverted can to exclude large particles.

  7. Emerging ST121/agr4 community-associated methicillin-resistant Staphylococcus aureus (MRSA) with strong adhesin and cytolytic activities: trigger for MRSA pneumonia and fatal aspiration pneumonia in an influenza-infected elderly.

    PubMed

    Wan, T-W; Tomita, Y; Saita, N; Konno, K; Iwao, Y; Hung, W-C; Teng, L-J; Yamamoto, T

    2016-09-01

    The pathogenesis of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) pneumonia in influenza-infected elderly individuals has not yet been elucidated in detail. In the present study, a 92-year-old man infected with influenza developed CA-MRSA pneumonia. His CA-MRSA was an emerging type, originated in ST121/agr4 S. aureus, with diversities of Panton-Valentine leucocidin (PVL)(-)/spat5110/SCCmecV(+) versus PVL(+)/spat159((etc.))/SCCmec (-), but with common virulence potentials of strong adhesin and cytolytic activities. Resistance to erythromycin/clindamycin (inducible-type) and gentamicin was detected. Pneumonia improved with the administration of levofloxacin, but with the subsequent development of fatal aspiration pneumonia. Hence, characteristic CA-MRSA with strong adhesin and cytolytic activities triggered influenza-related sequential complications. PMID:27358743

  8. A method for the concentration of fine-grained rutile (TiO2) from sediment and sedimentary rocks by chemical leaching

    USGS Publications Warehouse

    Commeau, Judith A.; Valentine, Page C.

    1991-01-01

    Most of the sample analyzed by the method described were marine muds collected from the Gulf of Maine (Valentine and Commeau, 1990). The silt and clay fraction (up to 99 wt% of the sediment) is composed of clay minerals (chiefly illite-mica and chlorite), silt-size quartz and feldspar, and small crystals (2-12 um) of rutile and hematite. The bulk sediment samples contained an average of 2 to 3 wt percent CaCO3. Tiher samples analyzed include red and gray Carboniferous and Triassic sandstones and siltstones exposed around the Bay of Fundy region and Paleozoic sandstones, siltstones, and shales from northern Maine and New Brunswick. These rocks are probable sources for the fine-grained rutile found in the Gulf of Maine.

  9. Consensual Nonmonogamy: Psychological Well-Being and Relationship Quality Correlates.

    PubMed

    Rubel, Alicia N; Bogaert, Anthony F

    2015-01-01

    Consensually nonmonogamous relationships are those in which all partners explicitly agree that each partner may have romantic or sexual relationships with others (Conley, Ziegler, Moors, Matsick, & Valentine, 2013 ). In this article, research examining the associations between consensual nonmonogamy, psychological well-being, and relationship quality is reviewed. Specifically, three types of consensual nonmonogamy are examined: swinging, open relationships (including sexually open marriage and gay open relationships), and polyamory. Swinging refers to when a couple practices extradyadic sex with members of another couple; open relationships are relationships in which partners agree that they can have extradyadic sex; and polyamory is the practice of, belief in, or willingness to engage in consensual nonmonogamy, typically in long-term and/or loving relationships. General trends in the research reviewed suggest that consensual nonmonogamists have similar psychological well-being and relationship quality as monogamists. Methodological challenges in research on consensual nonmonogamy and directions for future research are discussed. PMID:25189189

  10. The naming game: A discrepancy among the medical community.

    PubMed

    Loukas, Marios; Aly, Islam; Tubbs, R Shane; Anderson, Robert H

    2016-04-01

    As anatomists we rely on the nomenclature of structures in order to describe them appropriately, particularly their orientation in respect to their surrounding. The terminology used by the anatomist to describe an organ, muscle, or nerve within the body is taught to medical students as law. Students learn to describe structures in the "anatomical position", which has been accepted in the literature since the original Latin Nomina Anatomica. They therefore familiarize themselves with the use of terms such as superior, inferior, posterior and anterior to describe all anatomical structures, except in respect of the heart. The heart is still described in the original Valentine position. As anatomists we owe it to the medical and research community to correct the nomenclature to minimize confusion, and to describe the heart properly in respect to its surrounding structures. Clin. Anat. 29:285-289, 2016. © 2015 Wiley Periodicals, Inc. PMID:26579876

  11. Site Description for the University of Nebraska's Sandhills Agricultural Laboratory

    NASA Technical Reports Server (NTRS)

    Gardner, B. R.; Blad, B. L.

    1985-01-01

    The Sandhills Agricultural Laboratory is operated by the University of Nebraska. The laboratory is located in the south-central part of the Nebraska Sandhills near Tryon, Nebraska (41 deg. 37' N; 100 deg. 50' W). The laboratory is surrounded on the west and south by native rangeland vegetation, on the south by a large field of corn irrigated by a center pivot, and on the east by wheat stubble. This site is appropriate for moisture stress studies since rainfall is almost always inadequate to meet evaporative demands of agricultural crops during most of the growing season and the sandy soils (Valentine fine sand) at the site do not store large quantities of water. Various levels of water stress are achieved through irrigation from solid set sprinklers.

  12. A Case of Acute Pyogenic Sacroiliitis and Bacteremia Caused by Community-Acquired Methicillin-Resistant Staphylococcus aureus

    PubMed Central

    Kim, Suyoung; Lee, Kang Lock; Baek, Hae Lim; Jang, Seung Jun; Moon, Song Mi

    2013-01-01

    Pyogenic sacroiliitis is a rare osteoarticular infection, occurring most frequently in children and young adults. Diagnosis of the disease is challenging because of a general lack of awareness of the disease and its nonspecific signs and symptoms. Staphylococcus aureus is the most common causative bacteria in pyogenic sacroiliitis. Methicillin-resistant S. aureus (MRSA) has typically been considered a hospital-associated pathogen; however, community-acquired (CA)-MRSA infections are becoming increasingly common in Korea. We report the first domestic case of acute pyogenic sacroiliitis with abscess and bacteremia caused by CA-MRSA. The pathogen carried the type IV-A staphylococcal cassette chromosome mec (SCCmec) without the Panton-Valentine leukocidin (PVL) gene, and was identified as sequence type (ST) 72 by multilocus sequence typing. PMID:24475359

  13. Antimicrobial activity of tigecycline against community-acquired methicillin-resistant Staphylococcus aureus isolates recovered from North American medical centers.

    PubMed

    Mendes, Rodrigo E; Sader, Helio S; Deshpande, Lalitagauri; Jones, Ronald N

    2008-04-01

    A total of 1989 community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) were susceptibility tested by broth microdilution. Pulsed-field gel electrophoresis, SCCmec type, and polymerase chain reaction for Panton-Valentine leukocidin (PVL) genes were also performed. The overall tigecycline susceptibility rate was 98.2%. Glycopeptides, quinupristin/dalfopristin, linezolid, and chloramphenicol were also active against this collection (< or =0.7% resistant). The vast majority (70.8%) of the CA-MRSA was SCCmec type IV, from which 88.4% belonged to the USA300-0114 clone and 94.7% were PVL positive. Tigecycline showed in vitro activity comparable with other highly active parenteral agents and represents an option for treating complicated infections caused by CA-MRSA. PMID:18068326

  14. Draft genome sequence of Staphylococcus aureus KT/312045, an ST1-MSSA PVL positive isolated from pus sample in East Coast Malaysia.

    PubMed

    Suhaili, Zarizal; Lean, Soo-Sum; Mohamad, Noor Muzamil; Rachman, Abdul R Abdul; Desa, Mohd Nasir Mohd; Yeo, Chew Chieng

    2016-09-01

    Most of the efforts in elucidating the molecular relatedness and epidemiology of Staphylococcus aureus in Malaysia have been largely focused on methicillin-resistant S. aureus (MRSA). Therefore, here we report the draft genome sequence of the methicillin-susceptible Staphylococcus aureus (MSSA) with sequence type 1 (ST1), spa type t127 with Panton-Valentine Leukocidin (pvl) pathogenic determinant isolated from pus sample designated as KT/314250 strain. The size of the draft genome is 2.86 Mbp with 32.7% of G + C content consisting 2673 coding sequences. The draft genome sequence has been deposited in DDBJ/EMBL/GenBank under the accession number AOCP00000000. PMID:27508119

  15. Halo naevi, vitiligo and diffuse alopecia areata associated with tocilizumab therapy

    PubMed Central

    Nadesalingam, Kavitha; Goodfield, Mark; Emery, Paul

    2016-01-01

    We present a follow-up case report of a 33-year-old lady with juvenile onset arthritis who developed halo naevi while on treatment with tocilizumab. This case report describes the development of halo naevi, vitiligo and diffuse alopecia areata associated with tocilizumab therapy following infection with Methicillin-resistant Staphylococcus aureus (MRSA) and Panton–Valentine leukocidin positivity. This is the first case that describes these events and supports previous theories on cellular and humoral immunity as causative factors. The regression of melanocytes during treatment with tocilizumab could also implicate IL-6 and sIL-6R as future targets in the treatment of melanoma through its direct effect of melanocytic cytotoxicity, which supports previous studies. PMID:27516894

  16. [Scientific, pedagogical, and surgical work of professor V.F.Voyno-Yasenetsky during the Great Patriotic War].

    PubMed

    Kosachev, I D; Gladkikh, P F; Iakovlev, A E

    2011-08-01

    The article is devoted to activities in the period 1941-1945. Krasnoyarsk and Tambov, a professor of surgery Valentine Feliksovich Voyno-Yasenetsky (Archbishop Luka)--doctor of medical sciences, laureate of the State (Stalin) Prize of the USSR, who made a significant contribution to the success of modern surgical science. A brilliant scholar and successor of the ideas of the outstanding scientist and surgeon Nikolai Pirogov, as in the Great Patriotic War surgeon and consultant evacuation hospitals, along with leading surgeons in the Soviet Union had a significant impact on the results of treatment of wounded soldiers and officers, thereby affecting the development of military field surgery. In our country it is rightfully considered the founder of contaminated surgery. PMID:22164990

  17. Early NACA human computers at work

    NASA Technical Reports Server (NTRS)

    1949-01-01

    The women of the Computer Department at NACA High-Speed Flight Research Station are shown busy with test flight calculations. The computers under the direction of Roxanah Yancey were responsible for accurate calculations on the research test flights made at the Station. There were no mechanical computers at the station in 1949, but data was reduced by human computers. Shown in this photograph starting at the left are: Geraldine Mayer and Mary (Tut) Hedgepeth with Friden calculators on the their desks; Emily Stephens conferring with engineer John Mayer; Gertrude (Trudy) Valentine is working on an oscillograph recording reducing the data from a flight. Across the desk is Dorothy Clift Hughes using a slide rule to complete data calculations. Roxanah Yancey completes the picture as she fills out engineering requests for further data.

  18. Accuracy of familiarity decisions to famous faces perceived without awareness depends on attitude to the target person and on response latency.

    PubMed

    Stone, Anna; Valentine, Tim

    2005-06-01

    Stone and Valentine (2004) presented masked 17 ms faces in simultaneous pairs of one famous and one unfamiliar face. Accuracy in selecting the famous face was higher when the famous person was regarded as "good" or liked than when regarded as "evil" or disliked. Experiment 1 attempted to replicate this phenomenon, but produced a different pattern of results. Experiment 2 investigated alternative explanations and found evidence supporting only the effect of response latency: responses made soon after stimulus onset were more accurate to liked than to disliked faces, whereas responses made after a longer delay were equally accurate to disliked faces. It appears that the effect of negative valence was corrected within the space of a few hundred milliseconds. Experiment 3, using an affective priming paradigm, supported the concept that an early-arising effect of valence is corrected if it is misleading to the directed task. PMID:15950887

  19. Blood and the Revenant in Walter Scott's The Fair Maid of Perth.

    PubMed

    Inglis, Katherine

    2014-01-01

    In Sir Walter Scott's The Fair Maid of Perth; or St Valentine's Day (1828), the resuscitated subject is referred to as a revenant, a term that Scott borrowed from Henry Thomson's Blackwoodian tale 'Le Revenant' (1827), meaning 'dead-alive'. Taking its cue from the sanguinary subtext of The Fair Maid of Perth, which is fascinated with the shedding of blood and transfusion of fluids, this chapter reads the Scottish revenant as a literary reflection on the extraordinary promise of blood transfusion in the 1820s: that death could be understood as a process, rather than an absolute state, and that medical intervention could restore life to those on the brink of death and even to the recently deceased. PMID:27132355

  20. Insertion of host DNA into PVL-encoding phages of the Staphylococcus aureus lineage ST80 by intra-chromosomal recombination.

    PubMed

    Wirtz, Christiane; Witte, Wolfgang; Wolz, Christiane; Goerke, Christiane

    2010-10-25

    Temperate bacteriophages play a critical role in the pathogenicity of the human pathogen Staphylococcus aureus by mediating positive lysogenic conversion for different virulence factors such as Panton-Valentine leukocidin (PVL) or by interrupting chromosomal virulence genes. PVL-encoding phages are integrated in the S. aureus genome within a conserved ORF which is surrounded by a cluster of tandemly repeated genes. Here we demonstrate that in S. aureus clonal complex ST80 strains PVL-phage induction led to the acquisition of host DNA into the phage genome probably due to a homologous recombination event between direct repeats of the two paralogous genes adjacent to the phage integration site. Phage excision was accompanied by an additional chromosomal deletion in this region. This so far unrecognized mechanism of DNA uptake into the phage genome may play an important role in the co-evolution of phages and bacteria. PMID:20708208

  1. Photographs of the Sea Floor of Western Massachusetts Bay, Offshore of Boston, Massachusett, July 1999

    USGS Publications Warehouse

    Gutierrez, Benjamin T.; Butman, Bradford; Blackwood, Dann S.

    2001-01-01

    This CD-ROM contains photographs and sediment sample analyses of the sea floor obtained at 142 sites in western Massachusetts Bay (Figure 1) during a research cruise (USGS cruise ISBL99024) aboard the Fishing Vessel (FV) Isabel S. (Figure 2) conducted July 18-21, 1999. These photographs and samples provide critical ground truth information for the interpretation of shaded relief and backscatter intensity maps created using data collected with a multibeam echo sounder system (Butman and others, in press, a, b, c; Valentine and others, in press, a, b, c). Collection of these photographs and samples was undertaken in support of a large project whose overall objective is to map and describe the sea floor of Massachusetts Bay.

  2. Precise leveling, space geodesy and geodynamics

    NASA Technical Reports Server (NTRS)

    Reilinger, R.

    1981-01-01

    The implications of currently available leveling data on understanding the crustal dynamics of the continental United States are investigated. Neotectonic deformation, near surface movements, systematic errors in releveling measurements, and the implications of this information for earthquake prediction are described. Vertical crustal movements in the vicinity of the 1931 Valentine, Texas, earthquake which may represent coseismic deformation are investigated. The detection of vertical fault displacements by precise leveling in western Kentucky is reported. An empirical basis for defining releveling anomalies and its implications for crustal deformation in southern California is presented. Releveling measurements in the eastern United States and their meaning in the context of possible crustal deformation, including uplift of the Appalachian Mountains, eastward tilting of the Atlantic Coastal Plain, and apparent movements associated with a number of structural features along the east coast, are reported.

  3. Daptomycin efficacy in the central nervous system of a patient with disseminated methicillin-resistant Staphylococcus aureus infection: a case report

    PubMed Central

    2012-01-01

    Introduction Staphylococcus aureus has emerged as a major nosocomial pathogen in the last decades and also represents the second most common pathogen isolated from patients in outpatient settings. Although methicillin-resistant S.aureus infections were traditionally limited to hospitals, community-associated cases of methicillin-resistant S.aureus infections have been reported. In our case, we observed an unexpected event during treatment. Case presentation A 60-year-old Caucasian man developed fever and multiple muscle and brain abscesses caused by Panton-Valentine leukocidin-negative community-associated methicillin-resistant S. aureus. Conclusion Although our patient was given antimicrobials active against the isolated methicillin-resistant S. aureus strain, it was only after the introduction of daptomycin that his skin, soft tissue and muscle lesions and also brain manifestations improved. PMID:22938025

  4. Peanut allergy as a trigger for the deterioration of atopic dermatitis and precursor of staphylococcal and herpetic associated infections - case report.

    PubMed

    Ferreira, Dennis; Abad, Eliane Dios; Cavalcante, Fernanda Sampaio; Dos Santos, Fabiana Monteiro; Saintive, Simone; Goudoris, Ekaterini; do Prado, Evandro Alves; Ribeiro, Marcia; Soares Rosado, Alexandre; van Elsas, Jan Dirk; Dos Santos, Kátia Regina Netto

    2015-01-01

    Atopic dermatitis (AD) is a multifactorial and chronic disease, with genetic, environmental, immunological and nutritional origins. AD may be aggravated by allergies associated with infections. This study aims to describe a paediatric case of AD in which the peanut allergy was the triggering factor to aggravate the disease, and was also the concomitant precursor of staphylococcal (methicillin-sensitive Staphylococcus aureus, carrier of the Panton-Valentine leukocidine (PVL) genes) and herpetic (Herpes Simplex - HSV) infections. The clinical management approach and nursing strategies promoted a favourable evolution during the hospitalization period, besides the family approach, which was essential to control any flare-up of the disease. Adherence to a recommended diet and the use of strategies to prevent any recurrent infections were important to ensure the patient's quality of life. PMID:26403117

  5. The temporal Doppler effect: when the future feels closer than the past.

    PubMed

    Caruso, Eugene M; Van Boven, Leaf; Chin, Mark; Ward, Andrew

    2013-04-01

    People routinely remember events that have passed and imagine those that are yet to come. The past and the future are sometimes psychologically close ("just around the corner") and other times psychologically distant ("ages away"). Four studies demonstrate a systematic asymmetry whereby future events are psychologically closer than past events of equivalent objective distance. When considering specific times (e.g., 1 year) or events (e.g., Valentine's Day), people consistently reported that the future was closer than the past. We suggest that this asymmetry arises because the subjective experience of movement through time (whereby future events approach and past events recede) is analogous to the physical experience of movement through space. Consistent with this hypothesis, experimentally reversing the metaphorical arrow of time (by having participants move backward through virtual space) completely eliminated the past-future asymmetry. We discuss how reducing psychological distance to the future may function to prepare people for upcoming action. PMID:23474832

  6. Meticillin-resistant Staphylococcus aureus isolated from Iranian hospitals: virulence factors and antibiotic resistance properties

    PubMed Central

    Momtaz, Hassan; Hafezi, Laleh

    2014-01-01

    Staphylococcus aureus is an important opportunistic pathogen responsible for a variety of diseases. Indiscriminate prescription of antibiotics caused severe antibiotic resistance especially against commonly used drugs. The present investigation was carried out to study the distribution of Panton-Valentine Leukocidin gene, SCCmec types and antibiotic resistance properties of meticillin-resistant Staphylococcus aureus isolated from Iranian hospitals. A total of 132 clinical specimens were collected from two major Iranian hospitals. Samples were cultured and their positive results were subjected to several PCR methods. The patterns of antibiotic resistance were studied using the disk diffusion method. We found that 66 out of 132 samples (50%) were positive for Staphylococcus aureus. The most commonly infected samples were superficial and surgical wounds (66.12%). The incidence of mecA, tetK, ermA, ermC, tetM, aacA-D, linA, msrA, vatA, vatC and vatB antibiotic resistance genes were 80.30%, 34.84%, 30.30%, 25.75%, 24.24%, 19.69%, 7.57%, 7.57%, 6.06%, 3.03% and 1.51%, respectively. Totally, 40.90% of isolates harbored the Panton-Valentine Leukocidin gene. Of 53 mec positive strains, the distribution of SCCmec V, SCCmec III, SCCmec IVa, SCCmec IVc and SCCmec IVb were 28 (52.83%), 13 (24.52%), 6 (11.32%), 4 (7.54%) and 2 (3.77%), respectively. All isolates were resistant to penicillin, cephalothin, cefazoline and ceftriaxone. The high levels of Staphylococcus aureus resistance against commonly used antibiotics as well as high presence of SCCmec types of meticillin-resistant virulent strains of Staphylococcus aureus suggest that infections with these strains require more advanced hospital care with emerging demand for novel antibiotics. PMID:25428674

  7. Possible healthcare-associated transmission as a cause of secondary infection and population structure of Staphylococcus aureus isolates from two wound treatment centres in Ghana.

    PubMed

    Kpeli, G; Darko Otchere, I; Lamelas, A; Buultjens, A L; Bulach, D; Baines, S L; Seemann, T; Giulieri, S; Nakobu, Z; Aboagye, S Y; Owusu-Mireku, E; Pluschke, G; Stinear, T P; Yeboah-Manu, D

    2016-09-01

    We have previously shown that secondary infections of Buruli ulcer wounds were frequently caused by Staphylococcus aureus. To gain understanding into possible routes of secondary infection, we characterized S. aureus isolates from patient lesions and surrounding environments across two Ghanaian health centres. One hundred and one S. aureus isolates were isolated from wounds (n = 93, 92.1%) and the hospital environment (n = 8, 7.9%) and characterized by the spa gene, mecA and the Panton-Valentine leucocidin toxin followed by spa sequencing and whole genome sequencing of a subset of 49 isolates. Spa typing and sequencing of the spa gene from 91 isolates identified 29 different spa types with t355 (ST152), t186 (ST88), and t346 dominating. Although many distinct strains were isolated from both health centres, genotype clustering was identified within centres. In addition, we identified a cluster consisting of isolates from a healthcare worker, patients dressed that same day and forceps used for dressing, pointing to possible healthcare-associated transmission. These clusters were confirmed by phylogenomic analysis. Twenty-four (22.8%) isolates were identified as methicillin-resistant S. aureus and lukFS genes encoding Panton-Valentine leucocidin were identified in 67 (63.8%) of the isolates. Phenotype screening showed widespread resistance to tetracycline, erythromycin, rifampicin, amikacin and streptomycin. Genomics confirmed the widespread presence of antibiotic resistance genes to β-lactams, chloramphenicol, trimethoprim, quinolone, streptomycin and tetracycline. Our findings indicate that the healthcare environment probably contributes to the superinfection of Buruli ulcer wounds and calls for improved training in wound management and infection control techniques. PMID:27547406

  8. Hunting for exploding red supergiant stars

    NASA Astrophysics Data System (ADS)

    Messineo, Maria; Menten, Karl M.; Figer, Donald F.; Ivanov, Valentin D.; Zhu, Qingfeng; Kudritzki, Rolf-Peter; Davies, Ben; Clark, J. Simon; Rich, Michael; Chen, Rosie; Trombley, Christine; MacKenty, John W.; Habing, Harm; Churchwell, Edward

    2015-08-01

    Red supergiants (RSGs) are among the brightest Galactic stars at infrared wavelengths. They lose mass at high-rates and, eventually, explode as supernovae, enriching the interstellar medium. I would like to present results on our ongoing searches for candidate obscured-far-luminous late-type stars, which are based on 2MASS, UKIDSS, and GLIMPSE data, on extinction-free colors(Messineo et al. 2012, A&A, 537) and on the analysis of the extinction curve along a given line-of-sight with clump stars. Messineo et al. (2014, A&A, 571, 43) spectroscopically confirmed two clusters of red supergiants, one on the Sagittarius-Carina spiral arm at a distance of ~7 kpc, and another on the Scutum-Crux arm at a distance of ~4 kpc; while Messineo et al. (2014, A&A, 569, 20) have, found several RSGs in the core of SNRs W41 and within the area covered by the SNR G22.7-0.2 in the GMC G23.3-0.3. SNR G22.7-0.2 appears to be most likely a type II SNR.Messineo , M.; Menten, K. M.; Churchwell, E.; Habing, H. 2012A&A...537A..10MMessineo, Maria; Zhu, Qingfeng; Ivanov, Valentin D.; Figer, Donald F.; Davies, Ben; Menten, Karl M.; Kudritzki, Rolf P.; Chen, C.-H. Rosie 2014A&A...571A..43MMessineo, Maria; Menten, Karl M.; Figer, Donald F.; Davies, Ben; Clark, J. Simon; Ivanov, Valentin D.; Kudritzki, Rolf-Peter; Rich, R. Michael; MacKenty, John W.; Trombley, Christine; 2014A&A...569A..20M

  9. Mapping seafloor volcanism and its record of tectonic processes

    NASA Astrophysics Data System (ADS)

    Kalnins, L. M.; Valentine, A. P.; Trampert, J.

    2013-12-01

    One relatively obvious surface reflection of certain types of tectonic and mantle processes is volcanic activity. Ocean covers two thirds of our planet, so naturally much of this evidence will be marine, yet the evidence of volcanic activity in the oceans remains very incompletely mapped. Many seamounts, the products of 'excess' volcanism, have been identified (10,000--20,000 over 1 km in height, depending on the study), but it is estimated that up to 60% of seamounts in this height range remain unmapped. Given the scale of the task, identification of probable seamounts is a process that clearly needs to be automated, but identifying naturally occurring features such as these is difficult because of the degree of inherent variation. A very promising avenue for these questions lies in the use of learning algorithms, such as neural networks, designed to have complex pattern recognition capabilities. Building on the work of Valentine et al. (2013), we present preliminary results of a new global seamount study based on neural network methods. Advantages of this approach include an intrinsic measure of confidence in the seamount identification and full automation, allowing easy re-picking to suit the requirements of different types of studies. Here, we examine the resulting spatial and temporal distribution of marine volcanism and consider what insights this offers into the shifting patterns of plate tectonics and mantle activity. We also consider the size distribution of the seamounts and explore possible classes based on shape and their distributions, potentially reflecting both differing formational processes and later erosional processes. Valentine, A. P., L. M. Kalnins, and J. Trampert (2013), Discovery and analysis of topographic features using learning algorithms: A seamount case study, Geophysical Research Letters, 40(12), p. 3048--3054.

  10. Functional independence within the self-memory system: new insights from two cases of developmental amnesia.

    PubMed

    Picard, Laurence; Mayor-Dubois, Claire; Maeder, Philippe; Kalenzaga, Sandrine; Abram, Maria; Duval, Céline; Eustache, Francis; Roulet-Perez, Eliane; Piolino, Pascale

    2013-06-01

    Neuropsychological and neuroimaging data suggest that the self-memory system can be fractionated into three functionally independent systems processing personal information at several levels of abstraction, including episodic memories of one's life (episodic autobiographical memory, EAM), semantic knowledge of facts about one's life (semantic autobiographical memory, SAM), and semantic knowledge of one's personality [conceptual self, (CS)]. Through the study of two developmental amnesic patients suffering of neonatal brain injuries, we explored how the different facets of the self-memory system develop when growing up with bilateral hippocampal atrophy. Neuropsychological evaluations showed that both of them suffered from dramatic episodic learning disability with no sense of recollection (Remember/Know procedure), whereas their semantic abilities differed, being completely preserved (Valentine) or not (Jocelyn). Magnetic resonance imaging, including quantitative volumetric measurements of the hippocampus and adjacent (entorhinal, perirhinal, and temporopolar) cortex, showed severe bilateral atrophy of the hippocampus in both patients, with additional atrophy of adjacent cortex in Jocelyn. Exploration of EAM and SAM according to lifetime periods covering the entire lifespan (TEMPAu task, Piolino et al., 2009) showed that both patients had marked impairments in EAM, as they lacked specificity, details and sense of recollection, whereas SAM was completely normal in Valentine, but impaired in Jocelyn. Finally, measures of patients' CS (Tennessee Self-Concept Scale, Fitts and Warren, 1996), checked by their mothers, were generally within normal range, but both patients showed a more positive self-concept than healthy controls. These two new cases support a modular account of the medial-temporal lobe with episodic memory and recollection depending on the hippocampus, and semantic memory and familiarity on adjacent cortices. Furthermore, they highlight developmental

  11. Napoli and Volcanism - Vesuvius and Mt. Etna

    NASA Technical Reports Server (NTRS)

    2002-01-01

    For more than 240 million years the region now known as Italy has been the scene of episodic volcanic activity. East-southeast of Napoli (Naples) stands the imposing cone of Vesuvius, which erupted explosively in 79 A.D. to bury Pompeii and Herculaneum. More recently, when the crew of Space Shuttle mission STS-104 captured this view, Mt. Etna (Sicily, not seen in this image, but photographed the day before) was spewing ash and gas thousands of meters into the air, some of which can be seen as a brownish smear over Isola d' Ischia and the Tyrrhenian Sea. The Appenine ranges extend from northern Italy, down the boot of the peninsula and westward into Sicily. This photograph of the Appenino Napoletano is part of an 18-frame stereophoto mapping strip that spans the entire mountain chain. The almost 1200-km-long belt of volcanoes and folded/faulted mountains is a result of the ongoing collision of Africa and Eurasia, accompanied by the progressive closing of the Mediterranean Sea. Using overlapping pairs of stereophotos, and a special viewer, scientists can get a three-dimensional perspective on the ranges that surpasses any image viewed alone. For more information, see another image of Mt. Vesuvius, taken by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). References: Behncke, Boris, 2000, Vesuvio - The eruption of A.D. 79: Italy's Volcanoes - The Cradle of Volcanology [http://www.geo.mtu.edu/boris/VESUVIO_79.html (accessed 10/18/01)] Doglioni, C., and Flores, G., 1997, Italy, in Moores, E. M., and Fairbridge, R. W., editors, Encyclopedia of European and Asian Regional Geology: London, Chapman and Hall, p. 414-435 Shuttle photograph STS104-710-60 was taken 23 July 2001 from the orbiter Atlantis using a Hasselblad camera with 250-mm lens. The image is provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. The entire mapping series (of frames numbered in sequence from 50 through 68) can also be downloaded from the

  12. CALL FOR PAPERS: Progress in Supersymmetric Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    2003-12-01

    This is a call for contributions to a special issue of Journal of Physics A: Mathematical and General dedicated to the subject of Supersymmetric Quantum Mechanics as featured in the International Conference in Supersymmetric Quantum Mechanics (PSQM03), 15--19 July 2003, University of Valladolid, Spain (http://metodos.fam.cie.uva.es/~susy_qm_03/). Participants at that meeting, as well as other researchers working in this area or in related fields, are invited to submit a research paper to this issue. The Editorial Board has invited Irina Areféva, David J Fernández, Véronique Hussin, Javier Negro, Luis M Nieto and Boris F Samsonov to act as Guest Editors for the special issue. Their criteria for acceptance of contributions are as follows: bullet The subject of the paper should be in the general area covered by the PSQM03 conference. bullet Contributions will be refereed and processed according to the usual mechanisms of the journal. bullet Papers should present substantial new results (they should not be simply reviews of authors' own work that is already published elsewhere). The guidelines for the preparation of contributions are as follows: bullet DEADLINE for submission of contributions is 15 January 2004. This deadline will allow the special issue to appear in approximately September 2004. bullet There is a page limit of 15 pages per research contribution. Further advice on publishing your work in Journal of Physics A: Mathematical and General may be found at www.iop.org/Journals/jphysa. bullet Contributions to the special issue should if possible be submitted electronically at www.iop.org/Journals/jphysa or by e-mail to jphysa@iop.org, quoting `JPhysA special issue --- PSQM03'. Submissions should ideally be in either standard LaTeX form or Microsoft Word. Please see the web site for further information on electronic submissions. bullet Authors unable to submit by email may send hard copy contributions to: Journal of Physics A, Institute of Physics Publishing

  13. Paper Birch Decline in the Niobrara River Valley, Nebraska: Weather, Microclimate, and Birch Stand Conditions

    USGS Publications Warehouse

    Stroh, Esther D.; Miller, Joel P.

    2009-01-01

    The Niobrara River Valley in north-central Nebraska supports scattered stands of paper birch (Betula papyrifera Marsh), a species more typical of boreal forests. These birch stands are considered to be relictual populations that have persisted since the end of the Wisconsin glaciation, when regional flora was more boreal in nature (Wright 1970, Kaul and others, 1988). Dieback of canopy-sized birch has been observed throughout the Niobrara Valley in recent years, although no onset dates are documented. The current dieback event probably started around or after the early 1980's. The study objectives were to understand microclimatic conditions in birch stands relative to nearby weather stations and historic weather conditions, and to assess current health conditions of individual birch trees. Temperature was measured every half-hour from June 2005 through October 2007 in 12 birch stands and individual birch tree health was measured as expressed by percent living canopy in these and 13 additional stands in spring 2006 and 2007. Birch site microclimate was compared to data from a National Weather Service station in Valentine, Nebraska, and to an automated weather station at The Nature Conservancy Niobrara Valley Preserve 24 kilometers north of Johnstown, Nebraska. Historic weather data from the Valentine station and another National Weather Service Station at Ainsworth, Nebraska, were used to reconstruct minimum and maximum temperature at The Nature Conservancy and one microclimate monitoring station using Kalman filtering and smoothing algorithms. Birch stand microclimate differed from local weather stations as well as among stands. Birch health was associated with annual minimum temperature regimes; those stands whose annual daily minimum temperature regimes were most like The Nature Conservancy station contained smaller proportions of living trees. Frequency of freeze/thaw conditions capable of inducing rootlet injury and subsequent crown dieback significantly have

  14. [MRSA clones identified in outpatient dermatology clinics].

    PubMed

    Hosoya, Shino; Ito, Teruyo; Misawa, Shigeki; Yoshiike, Takashi; Oguri, Toyoko; Hiramatsu, Keiichi

    2014-11-01

    To know the characteristics of methicillin-resistant Staphylococcus aureus (MRSA) strains disseminating through the Japanese community, we have determined types of Staphylococcal cassette chromosome mec (SCCmec) elements, Multi-Locus Sequence Typing (MLST), and carriages of four exotoxin genes (toxic-shock syndrome toxin, Panton-Valentine Leukocidine, and exfoliative toxins a and b) using 54 MRSA strains isolated from outpatients attending dermatology clinics at the four university hospitals of Juntendo University. Ten clonal complexes and 12 SCCmec types have been identified. As a result, more than 15 MRSA clones that were defined by the combination of genotype and SCCmec type, were identified. Among them, Clonal Complex (CC) 5-type IIa SCCmec strains were the most major (16 strains). In contrast to the fact that CC5- type IIa SCCmec strains known as a hospital-associated MRSA clone in Japan carried toxic-shock syndrome toxin gene (tst), only 2 of 16 strains have been shown to carry tst. Thirty-eight (70.4%) of isolates belonged to the clones distinct from the CC5-type IIa SCCmec strains. Among them, CC8 strains were major (12 strains), which contained 9 tst-positive CC8-type IVl SCCmec clones and a CC8-type IVa SCCmec strain carrying the Panton Valentine Leukocidin gene (lukS, F-PV). Clones related to impetigo were also identified: 7 exfoliative toxin b (etb) -positive clones, CC89-type IIa SCCmec and CC89-type V SCCmec strains; and 2 exfoliative toxin a (eta) -positive CC121-type V SCCmec strains. Other clones were as follows: CC1-type IVa SCCmec, CC8-type I SCCmec, CC81-type IVg SCCmec, CC97-type IVc SCCmec, CC91-type IVa SCCmec, CC59-type IVg SCCmec, CC45-type IIn SCCmec, CC89-SCCmec nontypeable, and CC8-type IVm, novel subtype of type IV SCCmec were identified in this study. Our data showed that many novel MRSA clones have emerged in the community. PMID:25764806

  15. Evolved massive stars in W33 and in GMC 23.3-0.3

    NASA Astrophysics Data System (ADS)

    Messineo, Maria; Clark, J. Simon; Figer, Donald F.; Menten, Karl M.; Kudritzki, Rolf-Peter; Najarro, Francisco; Rich, Michael; Ivanov, Valentin D.; Valenti, Elena; Trombley, Christine; Chen, Rosie; Davies, Ben; MacKenty, John W.

    2015-08-01

    We have conducted an infrared spectroscopic survey for massive evolved stars and/or clusters in the Galactic giant molecular clouds G23.3-0.3 and W33. A large number of extraordinary sub-clumps/clusters of massive stars were detected. The spatial and temporal distribution of these massive stars yields information on the star formation history of the clouds.In G23.3-0.3, we discovered a dozen massive O-type stars, one candidate luminous blue variable, and several red supergiants. The O-type stars have masses from 25 to 50 Msun and ages of 5-8 Myr, while the RSGs belong to a burst that occurred 20-30 Myr ago. Therefore, GMC G23.3-0.3 has had one of the longest known histories of star formation (20-30 Myr). GMC G23.3-0.3 is rich in HII regions and supernova remnants; we detected massive stars in the cores of SNR W41 and of SNR G22.7-0.2.In W33, we detected a few evolved O-type stars and one Wolf-Rayet star, but none of the late-type objects has the luminosity of a red supergiant. W33 is characterized by discrete sources and has had at least 3-5 Myr of star formation history, which is now propagating from west to east. While our detections of massive evolved stars in W33 are made on the west side of the cloud, several dense molecular cores that may harbor proto clusters have recently been detected on the east side of the cloud by Immer et al. (2014).Messineo, Maria; Menten, Karl M.; Figer, Donald F.; Davies, Ben; Clark, J. Simon; Ivanov, Valentin D.Kudritzki, Rolf-Peter; Rich, R. Michael; MacKenty, John W.; Trombley, Christine 2014A&A...569A..20MMessineo, Maria; Clark, J. Simon; Figer, Donald F.; Kudritzki, Rolf-Peter; Francisco, Najarro; Rich, R. Michael; Menten, Karl M.; Ivanov, Valentin D.; Valenti, Elena; Trombley, Christine; Chen, C.H. Rosie; Davies, Ben; submitted to ApJ.

  16. Development of a SCAR marker for male gametophyte of Gracilariopsis lemaneiformis based on AFLP technique

    NASA Astrophysics Data System (ADS)

    Zhou, Wei; Ding, Hongye; Sui, Zhenghong; Wang, Zhongxia; Wang, Jinguo

    2014-05-01

    The red alga Gracilariopsis lemaneiformis (Bory) is an economically valuable macroalgae. As a means to identify the sex of immature Gracilariopsis lemaneiformis, the amplified fragment length polymorphism (AFLP) technique was used to search for possible sex- or phase-related markers in male gametophytes, female gametophytes, and tetrasporophytes, respectively. Seven AFLP selective amplification primers were used in this study. The primer combination E-TG/M-CCA detected a specific band linked to male gametophytes. The DNA fragment was recovered and a 402-bp fragment was sequenced. However, no DNA sequence match was found in public databases. Sequence characterized amplified region (SCAR) primers were designed from the sequence to test the repeatability of the relationship to the sex, using 69 male gametophytes, 139 female gametophytes, and 47 tetrasporophytes. The test results demonstrate a good linkage and repeatability of the SCAR marker to sex. The SCAR primers developed in this study could reduce the time required for sex identification of Gracilariopsis lemaneiformis by four to six months. This can reduce both the time investment and number of specimens required in breeding experiments.

  17. STS-106 crew gathers to greet family members

    NASA Technical Reports Server (NTRS)

    2000-01-01

    While meeting with family on the day before launch, the STS-106 crew poses for a photo. Waving, left to right, are Mission Specialist Richard A. Mastracchio, Commander Terrence W. Wilcutt, Pilot Scott D. Altman, and Mission Specialists Edward T. Lu, Yuri I. Malenchenko, Boris V. Morukov and Daniel C. Burbank. Malenchenko and Morukov are with the Russian Aviation and Space Agency. In the background (left) is Launch Pad 39B and Space Shuttle Atlantis, with the Rotating Service Structure still in place. STS-106 is scheduled to launch Sept. 8, 2000, at 8:45 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall. Landing is targeted for Sept. 19 at 4:59 a.m. EDT at the KSC Shuttle Landing Facility.

  18. Comparison of Electron Cloud Simulation and Experiments in the High-Current Experiment

    SciTech Connect

    Cohen, R H; Friedman, A; Covo, M K; Lund, S M; Molvik, A W; Bieniosek, F M; Seidl, P A; Vay, J; Stoltz, P; Veitzer, S

    2004-11-11

    Contaminating clouds of electrons are a common concern for accelerators of positive-charged particles, but there are some unique aspects of heavy-ion accelerators for fusion and high-energy density physics which make modeling such clouds especially challenging. In particular, self-consistent electron and ion simulation is required, including a particle advance scheme which can follow electrons in regions where electrons are strongly, weakly, and un-magnetized. We describe our approach to such self-consistency, and in particular a scheme for interpolating between full-orbit (Boris) and drift-kinetic particle pushes that enables electron time steps long compared to the typical gyro period in the magnets. We present tests and applications: simulation of electron clouds produced by three different kinds of sources indicates the sensitivity of the cloud shape to the nature of the source; first-of-a-kind self-consistent simulation of electron-cloud experiments on the High-Current Experiment (HCX) at LBNL, in which the machine can be flooded with electrons released by impact of the ion beam on an end plate, demonstrate the ability to reproduce key features of the ion-beam phase space; and simulation of a two-stream instability of thin beams in a magnetic field demonstrate the ability of the large-timestep mover to accurately calculate the instability.

  19. Simulating Electron Clouds in Heavy-Ion Accelerators

    SciTech Connect

    Cohen, R.H.; Friedman, A.; Kireeff Covo, M.; Lund, S.M.; Molvik,A.W.; Bieniosek, F.M.; Seidl, P.A.; Vay, J-L.; Stoltz, P.; Veitzer, S.

    2005-04-07

    Contaminating clouds of electrons are a concern for most accelerators of positive-charged particles, but there are some unique aspects of heavy-ion accelerators for fusion and high-energy density physics which make modeling such clouds especially challenging. In particular, self-consistent electron and ion simulation is required, including a particle advance scheme which can follow electrons in regions where electrons are strongly-, weakly-, and un-magnetized. They describe their approach to such self-consistency, and in particular a scheme for interpolating between full-orbit (Boris) and drift-kinetic particle pushes that enables electron time steps long compared to the typical gyro period in the magnets. They present tests and applications: simulation of electron clouds produced by three different kinds of sources indicates the sensitivity of the cloud shape to the nature of the source; first-of-a-kind self-consistent simulation of electron-cloud experiments on the High-Current Experiment (HCX) at Lawrence Berkeley National Laboratory, in which the machine can be flooded with electrons released by impact of the ion beam and an end plate, demonstrate the ability to reproduce key features of the ion-beam phase space; and simulation of a two-stream instability of thin beams in a magnetic field demonstrates the ability of the large-timestep mover to accurately calculate the instability.

  20. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    At the 195-foot level of Launch Pad 39B, STS-106 Mission Specialists Edward T. Lu (left) reaches for a lever to release the slidewire basket . At right is Richard A. Mastracchio (right) already seated. The basket is part of the emergency egress equipment from the orbiter. In the background can be seen Mission Specialist Boris V. Morukov in another slidewire basket. They and the rest of the STS-106 crew are taking part in Terminal Countdown Demonstration Activities (TCDT), which includes emergency egress training, along with opportunities to inspect their mission payload in the orbiter'''s payload bay, and a simulated launch countdown. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  1. Einstein studies in Russia

    NASA Astrophysics Data System (ADS)

    Balashov, Yuri; Vizgin, Vladimir

    This volume presents a selection of the best contributions by Russian scholars - historians and philosophers of science - to the Einstein Studies industry, broadly construed. Many of the papers were first published in Russian, in the Einshteinovskiy Sbornik series (Einstein Studies) initiated by I. Tamm in 1966. This book explores the historical and foundational issues in general relativity and relativistic cosmology, Einstein's contributions to quantum theory of radiation, and the rise of Dirac's quantum electrodynamics. It also includes a detailed description of the physics colloquium Einstein established and coordinated in 1912- 1914 in Zürich. The contributors draw extensively on documentation previously unavailable to most scholars. Materials from various Russian archives shed new light on the famous exchange (regarding the first evolutionary cosmological models) between Einstein and Alexander Friedmann in the early 1920's and on the role of Boris Podolsky and Vladimir Fock in the emergence of quantum electrodynamics. The little-known correspondence between Einstein and a famous German pilot Paul Erhardt suggests that during World War I, the former was involved with aero- and hydrodynamics research and ways of improving airplane design. Other articles introduce new approaches to important foundational questions in general relativity and cosmology. Historians, philosophers, and sociologists of science will find much new and unexpected material in this engaging volume presenting the best of recent Russian scholarship in the field. The book is also very accessible to the general reader.

  2. Challenges of PIC Simulations at High Laser Intensity

    NASA Astrophysics Data System (ADS)

    Luedtke, Scott V.; Arefiev, Alexey V.; Toncian, Toma; Hegelich, Bjorn Manuel

    2015-11-01

    New lasers with very high intensity pulses (I >1022 W/cm2) are being commissioned to explore new regimes of laser-matter interactions. These lasers require accurate particle-in-cell (PIC) simulations, which may require new computational approaches to efficiently produce physically accurate results. We examine the constraints on PIC simulations at high field intensity imposed by both the particle pusher and field solver. As proposed by Arefiev, et al. (Physics of Plasmas 22, 013103 (2015)), we implement adaptive sub-cycling in the Boris pusher of the EPOCH code and demonstrate its effectiveness in efficiently reducing errors from the pusher. It is well know that the use of a finite-difference scheme also modifies the electromagnetic wave dispersion relation. We examine the effect of the resulting discrepancy in the phase velocity on electron acceleration, and demonstrate that relatively small errors in the phase velocity lead to substantial changes in the electron energy gain from the laser pulse. We discuss the corresponding conditions for the field solver. These results are relevant to direct laser acceleration and underdense ionization experiments. This work was supported by NNSA cooperative agreement DE-NA0002008, the Defense Advanced Research Projects Agency's PULSE program (12-63-PULSE-FP014) and the Air Force Office of Scientific Research (FA9550-14-1-0045).

  3. A look behind the arms control agenda at the US-Russian and Sino-US summits

    SciTech Connect

    1995-11-01

    When President Bill Clinton met in New York with Russian President Boris Yeltsin on October 23 and Chinese President Jiang Zemin the following day, the leaders discussed a broad spectrum of arms control issues-including START II ratification, limits on Russian conventional weapons in the Caucasus, the nuclear test ban treaty, nuclear exports to Iran and NATO expansion. The crisis in Bosnia, however, dominated the administration`s pre- and post-summit briefings as well as the media`s coverage of the meetings. On October 20, the Arms Control Association (ACA) held a news conference to highlight the key arms control issues involved in the two sets of talks. Because these vital national security issues were virtually ignored by the press, the ACA press briefing remains the most comprehensive coverage of the full range of issues that were, in fact, addressed at the mini-summits. Panel speakers included Spurgeon M. Keeny, Jr., ACA president and executive director and former deputy director of the Arms Control and Disarmament Agency; Jack Mendelsohn, ACA deputy director and a former member of the US SALT II and START I delegations; Stanley Resor, ACA board chairman and former chief US delegate to the Mutual and Balanced Force Reduction talks, former defense undersecretary for policy and former secretary of the Army; and William Dircks, director of the Atlantic Council`s Program on Nuclear Policy and former deputy director general of the International Atomic Energy Agency. Extended excerpts from their remarks follow.

  4. STS-101 crew take part in CEIT at SPACEHAB

    NASA Technical Reports Server (NTRS)

    1999-01-01

    During a Crew Equipment Interface Test (CEIT) at SPACEHAB, in Cape Canaveral, Fla., STS-101 crew members Edward Tsang Lu (Ph.D.) and Yuri Malenchenko, who is with the Russian Space Agency (RSA) check out part of the Russian crane Strela. Other crew members are Commander James Donald Halsell Jr., Pilot Scott Horowitz, and Mission Specialists Jeffrey N. Williams, Mary Ellen Weber, (Ph.D.) and Boris W. Morukov, also with RSA. The primary objective of the STS-101 mission is to complete the initial outfitting of the International Space Station, making it fully ready for the first long-term crew. The seven-member crew will transfer almost two tons of equipment and supplies from SPACEHAB's Logistics Double Module. Additionally, they will unpack a shipment of supplies delivered earlier by a Russian Progress space tug and begin outfitting the newly arrived Zvezda Service Module. Three astronauts will perform two space walks to transfer and install parts of the Russian Strela cargo boom that are attached to SPACEHAB's Integrated Cargo Container, connect utility cables between Zarya and Zvezda, and install a magnetometer/pole assembly on the Service Module. Additional activities for the STS-101 astronauts include working with the Space Experiment Module (SEM-06) and the Mission to America's Remarkable Schools (MARS), two educational initiatives. STS-101 is scheduled for launch no earlier than March 16, 2000.

  5. STS-101 crew take part in CEIT at SPACEHAB

    NASA Technical Reports Server (NTRS)

    1999-01-01

    At SPACEHAB, in Titusville, Fla., STS-101 Mission Specialists Edward Tsang Lu (Ph.D.), Mary Ellen Weber (Ph.D.) and Boris W. Morukov, who is with the Russian Space Agency (RSA), stand inside the SPACEHAB Logistics Double Module, part of the payload for their mission. They and other crew members Commander James Donald Halsell Jr., Pilot Scott J. 'Doc' Horowitz (Ph.D.), and Mission Specialists Jeffrey N. Williams, and Yuri Malenchenko (also with RSA), are taking part in a Crew Equipment Interface Test. The primary objective of the STS-101 mission is to complete the initial outfitting of the International Space Station, making it fully ready for the first long-term crew. The seven-member crew will transfer almost two tons of equipment and supplies from SPACEHAB. Additionally, they will unpack a shipment of supplies delivered earlier by a Russian Progress space tug and begin outfitting the newly arrived Zvezda Service Module. Three astronauts will perform two space walks to transfer and install parts of the Russian Strela cargo boom that are attached to SPACEHAB's Integrated Cargo Container, connect utility cables between Zarya and Zvezda, and install a magnetometer/pole assembly on the Service Module. Additional activities for the STS-101 astronauts include working with the Space Experiment Module (SEM-06) and the Mission to America's Remarkable Schools (MARS), two educational initiatives. STS-101 is scheduled for launch no earlier than March 16, 2000.

  6. STS-101 crew take part in CEIT at SPACEHAB

    NASA Technical Reports Server (NTRS)

    1999-01-01

    During a Crew Equipment Interface Test (CEIT) at SPACEHAB, in Cape Canaveral, Fla., STS-101 crew members check out some of the cargo that will be carried on their mission. From left are Pilot Scott J. 'Doc' Horowitz (Ph.D.) and Mission Specialists Mary Ellen Weber, (Ph.D.), Jeffrey N. Williams, and Boris W. Morukov, who is with the Russian Space Agency (RSA). Other crew members are Commander James Donald Halsell Jr., Edward Tsang Lu (Ph.D.) and Yuri Malenchenko, also with RSA. The primary objective of the STS-101 mission is to complete the initial outfitting of the International Space Station, making it fully ready for the first long-term crew. The seven-member crew will transfer almost two tons of equipment and supplies from SPACEHAB's Logistics Double Module. Additionally, they will unpack a shipment of supplies delivered earlier by a Russian Progress space tug and begin outfitting the newly arrived Zvezda Service Module. Three astronauts will perform two space walks to transfer and install parts of the Russian Strela cargo boom that are attached to SPACEHAB's Integrated Cargo Container, connect utility cables between Zarya and Zvezda, and install a magnetometer/pole assembly on the Service Module. Additional activities for the STS-101 astronauts include working with the Space Experiment Module (SEM-06) and the Mission to America's Remarkable Schools (MARS), two educational initiatives. STS-101 is scheduled for launch no earlier than March 16, 2000.

  7. STS-101 crew take part in CEIT at SPACEHAB

    NASA Technical Reports Server (NTRS)

    1999-01-01

    During a Crew Equipment Interface Test (CEIT) at SPACEHAB, in Cape Canaveral, Fla., STS-101 crew members check out some of the cargo that will be carried on their mission. From left are Mission Specialists Boris W. Morukov, who is with the Russian Space Agency (RSA), Jeffrey N. Williams, and Yuri Malenchenko, also with RSA. Other crew members are Commander James Donald Halsell Jr., Pilot Scott J. 'Doc' Horowitz (Ph.D.) and Mission Specialists Mary Ellen Weber, (Ph.D.) and Edward Tsang Lu (Ph.D.). The primary objective of the STS-101 mission is to complete the initial outfitting of the International Space Station, making it fully ready for the first long-term crew. The seven-member crew will transfer almost two tons of equipment and supplies from SPACEHAB's Logistics Double Module. Additionally, they will unpack a shipment of supplies delivered earlier by a Russian Progress space tug and begin outfitting the newly arrived Zvezda Service Module. Three astronauts will perform two space walks to transfer and install parts of the Russian Strela cargo boom that are attached to SPACEHAB's Integrated Cargo Container, connect utility cables between Zarya and Zvezda, and install a magnetometer/pole assembly on the Service Module. Additional activities for the STS-101 astronauts include working with the Space Experiment Module (SEM-06) and the Mission to America's Remarkable Schools (MARS), two educational initiatives. STS-101 is scheduled for launch no earlier than March 16, 2000.

  8. STS-101 crew take part in CEIT at SPACEHAB

    NASA Technical Reports Server (NTRS)

    1999-01-01

    During a Crew Equipment Interface Test (CEIT) at SPACEHAB, in Cape Canaveral, Fla., members of the STS-101 crew learn how to manipulate the Russian crane Strela. At left is Yuri Malenchenko, who is with the Russian Space Agency (RSA); in the center is Edward Tsang Lu (Ph.D.); at right is Mission Specialist Jeffrey N. Williams. Other crew members are Commander James Donald Halsell Jr., Pilot Scott Horowitz, and Mission Specialists Mary Ellen Weber, (Ph.D.) and Boris W. Morukov (RSA). The primary objective of the STS-101 mission is to complete the initial outfitting of the International Space Station, making it fully ready for the first long-term crew. The seven-member crew will transfer almost two tons of equipment and supplies from SPACEHAB's Logistics Double Module. Additionally, they will unpack a shipment of supplies delivered earlier by a Russian Progress space tug and begin outfitting the newly arrived Zvezda Service Module. Three astronauts will perform two space walks to transfer and install parts of the Russian Strela cargo boom that are attached to SPACEHAB's Integrated Cargo Container, connect utility cables between Zarya and Zvezda, and install a magnetometer/pole assembly on the Service Module. Additional activities for the STS-101 astronauts include working with the Space Experiment Module (SEM-06) and the Mission to America's Remarkable Schools (MARS), two educational initiatives. STS-101 is scheduled for launch no earlier than March 16, 2000.

  9. Can anthropogenic aerosol concentrations effect the snowfall rate?

    NASA Astrophysics Data System (ADS)

    Lohmann, U.; Zhang, J.; Pi, J.

    2003-04-01

    The mesoscale model GESIMA is used to simulate microphysical properties of Arctic clouds and their effect on radiation. Different case studies during the FIRE.ACE/SHEBA project show that GESIMA is able to simulate the cloud boundaries, ice and liquid water content and effective radii in good agreement with observations. For two different aerosol scenarios, the simulation results show that the anthropogenic aerosol can alter microphysical properties of Arctic clouds, and consequently modify surface precipitation. Borys et al. (2000) proposed that anthropogenically-induced decreases in cloud droplet size inhibit the riming process. On the contrary, we find that the accretion of snow crystals with cloud droplets is increased in the polluted cloud due to its higher cloud droplet number concentration. Instead the autoconversion rate of cloud droplets and accretion of drizzle by snow decreases caused by the shut-down of the collision-coalescence process in the polluted cloud. The amount of precipitation reaching the surface as snow depends crucially on the crystal shape. If aggregates are assumed, then a 10-fold increase in aerosol concentration leads to an increase in accumulated snow by 40% after 7 hours of simulation whereas the snow amount decreases by 30% when planar crystals are assumed because of the larger accretion efficiency of snow crystals with cloud droplets in case of aggregates. We will also perform climate model simulations to estimate the importance of this effect globally.

  10. STS-106 Crew Portrait

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Five NASA astronauts and two cosmonauts representing the Russian Aviation and Space Agency take a break in training from their scheduled September 2000 visit to the International Space Station (ISS). Astronauts Terrence W. Wilcutt (right front), and Scott D. Altman (left front) are mission commander and pilot, respectively. On the back row (from the left) are mission specialists Boris V. Morukov, cosmonaut, along with astronauts Richard A. Mastracchio, Edward T. Lu, and Daniel C. Burbank, and cosmonaut Yuri I. Malenchenko. Morukov and Malenchenko represent the Russian Aviation and Space Agency. Launched aboard the Space Shuttle Atlantis on September 8, 2000 at 7:46 a.m. (CDT), the STS-106 crew successfully prepared the International Space Station (ISS) for occupancy. Acting as plumbers, movers, installers and electricians, they installed batteries, power converters, a toilet and a treadmill on the outpost. They also delivered more than 2,993 kilograms (6,600 pounds) of supplies. Lu and Malenchenko performed a space walk to connect power, and data and communications cables to the newly arrived Zvezda Service Module and the Station.

  11. Taxonomy and distribution of the genus Muelleria frenguelli

    USGS Publications Warehouse

    Spaulding, S.A.; Stoermer, E.F.

    1997-01-01

    Navicula gibbula Cleve and its allies have a number of morphological characters which are visible under the light microscope and distinguish them from taxa included in Navicula Bory sensu stricto. These include proximal raphe ends which are sharply and unilaterally hooked and often extend beyond the central area, as well as two apparently thickened longitudinal ribs which extend the length of the valve on either side of the raphe. With the use of the SEM additional well-defined characters of the N. gibbula complex become apparent. Distal raphe ends are bifurcate and the valve face and mantle possess bipartite walls similar to those in Neidium Pfitzer. Furthermore, the apparently thickened longitudinal ribs are actually hollow canals, a feature reminiscent of the longitudinal canals of Diploneis Ehrenberg. Characters of the group are particularly well-defined and distinct from those of other genera, justifying separation from Navicula. Based on the valve morphology of N. gibbula and all other members of the section Naviculae fistulatae McCall, we separate these taxa from Navicula and resurrect the genus Muelleria Frenguelli to include them.

  12. New Density Functionals with Broad Applicability in Chemistry (SOGGA11, SOGGA11-X, M11, M11-L) and Approaches to Open-Shell DFT

    NASA Astrophysics Data System (ADS)

    Truhlar, Donald

    2012-02-01

    The accuracy of density functional theory for practical applications is determined by the quality of the necessarily approximate exchange-correlation functional (``density functional'') being used, and the goal of functional development in chemical physics is to obtain a functional that is accurate for a broad range of chemistry and physics. In our work we consider molecular structures and solid-state lattice constants and band gaps, but we emphasize energetics for main-group and transition-metal chemistry, including thermochemistry and barrier heights, noncovalent interaction energies, and excitation energies. This lecture will discuss four new density functionals, each optimized to give the best across-the-board performance for a broad range of chemistry in their class of functional: SOGGA11, a generalized gradient approximation (GGA); SOGGA11-X, a global hybrid GGA; M11: a range-separated hybrid meta-GGA, and M11-L, a meta-GGA. SOGGA11 and M11-L are local functionals, and SOGGA11-X and M11 include some nonlocal Hartree--Fock exchange. To the extent that time permits, I may also discuss recent progress in the treatment of open-shell systems by density functional theory, including time-dependent DFT, open-shell SCF, and noncollinear DFT. This invited lecture is based on collaborative research carried out with Roberto Peverati, Sijie Luo, Ke Yang, Boris Averkiev, Yan Zhao, and Rosendo Valero.

  13. Measuring time of flight of fusion products in an inertial electrostatic confinement fusion device for spatial profiling of fusion reactions

    NASA Astrophysics Data System (ADS)

    Donovan, D. C.; Boris, D. R.; Kulcinski, G. L.; Santarius, J. F.; Piefer, G. R.

    2013-03-01

    A new diagnostic has been developed that uses the time of flight (TOF) of the products from a nuclear fusion reaction to determine the location where the fusion reaction occurred. The TOF diagnostic uses charged particle detectors on opposing sides of the inertial electrostatic confinement (IEC) device that are coupled to high resolution timing electronics to measure the spatial profile of fusion reactions occurring between the two charged particle detectors. This diagnostic was constructed and tested by the University of Wisconsin-Madison Inertial Electrostatic Confinement Fusion Group in the IEC device, HOMER, which accelerates deuterium ions to fusion relevant energies in a high voltage (˜100 kV), spherically symmetric, electrostatic potential well [J. F. Santarius, G. L. Kulcinski, R. P. Ashley, D. R. Boris, B. B. Cipiti, S. K. Murali, G. R. Piefer, R. F. Radel, T. E. Radel, and A. L. Wehmeyer, Fusion Sci. Technol. 47, 1238 (2005)]. The TOF diagnostic detects the products of D(d,p)T reactions and determines where along a chord through the device the fusion event occurred. The diagnostic is also capable of using charged particle spectroscopy to determine the Doppler shift imparted to the fusion products by the center of mass energy of the fusion reactants. The TOF diagnostic is thus able to collect spatial profiles of the fusion reaction density along a chord through the device, coupled with the center of mass energy of the reactions occurring at each location. This provides levels of diagnostic detail never before achieved on an IEC device.

  14. Late Quaternary History of River Discharge and Glaciation in the Southern Kara Sea, Arctic Ocean: Preliminary Results

    NASA Astrophysics Data System (ADS)

    Stein, R.; Niessen, F.; Dittmers, K.; Levitan, M.; Levitan, M.; Schoster, F.; Simstich, J.; Steinke, T.; Stepanets, O.

    2001-12-01

    Within the framework of the joint German-Russian project on "The Nature of Continental Run-Off from the Siberian Rivers and its Behavior in the Adjacent Arctic Basin (Siberian River Run-Off-SIRRO)", a multidisciplinary expedition with RV "Akademik Boris Petrov" was carried out in the Ob and Yenisei estuaries and the southern Kara Sea in August-September 2001. From the geological point of view, the variability of river discharge in relationship to climate change and the reconstruction of extent and history of glaciation in the southern Kara Sea during Late Quaternary times are major foci of interest. To reach these goals, an intensive sediment ecosounding (2-12 kHz) survey and sediment coring program has been performed. Based on profiling and sediment core data, the following preliminary statements can be given: (1) The extent of the eastern margin of the Barents Sea LGM Ice Sheet between 74 and 78oN can be mapped in detail. Different types of glacial to nonglacial facies can be distinguished. This ice barrier should have strongly influenced river discharge, diverted towards the NE probably into the Voronin Trough. (2) The local LGM (?) ice sheet on Taymyr Peninsula seems to be not connected with the Barents Sea Ice Sheet. (3) Siberian river discharge reached maximum values during the last deglaciation and displays distinct (cyclic) variability during Holocene times. Further detailed evaluation of the sediment echograph profiles as well as detailed sedimentological studies and AMS 14C datings will follow to support these ideas.

  15. Analysis of Electron Trajectories in Magnetized High Power Plasmas

    NASA Astrophysics Data System (ADS)

    Krueger, Dennis; Gallian, Sara; Trieschmann, Jan; Brinkmann, Ralf Peter

    2015-09-01

    High Power Impulse Magnetron Sputtering (HiPIMS) is an important example of magnetized technological plasmas. With HiPIMS the focus lies on the generation of a high density plasma with a remarkably high degree of ionization. It can be used for the deposition of thin films with superior density and quality. Theoretical approaches to the regime of magnetized low temperature plasmas encounter some fundamental difficulties, for example concerning the details of the magnetic field configuration, the strongly varying degree of magnetization, and the frequent wall interactions. A kinetic single particle model is used for the investigations. Single electron trajectories are analyzed with the widely used Boris algorithm within the magnetized zone above the target (racetrack). We further examine a configuration where symmetry breaking occurs due to a potential bump, which is rotating azimuthally around the racetrack (spoke). Observing the effects of this structure on the single electron motion may allow us to obtain further insight into this phenomenon. This work is supported by the German Research Foundation in the frame of the Collaborative Research Centre TRR 87.

  16. Expression of the CTCFL Gene during Mouse Embryogenesis Causes Growth Retardation, Postnatal Lethality, and Dysregulation of the Transforming Growth Factor β Pathway

    PubMed Central

    Sati, Leyla; Zeiss, Caroline; Yekkala, Krishna; Demir, Ramazan

    2015-01-01

    CTCFL, a paralog of CTCF, also known as BORIS (brother of regulator of imprinted sites), is a testis-expressed gene whose function is largely unknown. Its product is a cancer testis antigen (CTA), and it is often expressed in tumor cells and also seen in two benign human vascular malformations, juvenile angiofibromas and infantile hemangiomas. To understand the function of Ctcfl, we created tetracycline-inducible Ctcfl transgenic mice. We show that Ctcfl expression during embryogenesis results in growth retardation, eye malformations, multiorgan pathologies, vascular defects, and neonatal death. This phenotype resembles prior mouse models that perturb the transforming growth factor β (TGFB) pathway. Embryonic stem (ES) cells with the Ctcfl transgene reproduce the phenotype in ES cell-tetraploid chimeras. Transcriptome sequencing of the Ctcfl ES cells revealed 14 genes deregulated by Ctcfl expression. Bioinformatic analysis revealed the TGFB pathway as most affected by embryonic Ctcfl expression. Understanding the consequence of Ctcfl expression in nontesticular cells and elucidating downstream targets of Ctcfl could explain the role of its product as a CTA and its involvement in two, if not more, human vascular malformations. PMID:26169830

  17. Distinction between the Youngest Toba Tuff and Oldest Toba Tuff from northern Sumatra based on the area density of spontaneous fission tracks in their glass shards

    NASA Astrophysics Data System (ADS)

    Westgate, John A.; Pearce, Nicholas J. G.; Gatti, Emma; Achyuthan, Hema

    2014-09-01

    Determination of the area density of spontaneous fission tracks (ρs) in glass shards of Toba tephra is a reliable way to distinguish between the Youngest Toba Tuff (YTT) and the Oldest Toba Tuff (OTT). The ρs values for YTT, uncorrected for partial track fading, range from 70 to 181 tracks/cm2 with a weighted mean of 108 ± 5 tracks/cm2, based on 15 samples. Corrected ρs values for YTT are in the range of 77-140 tracks/cm2 with a weighted mean of 113 ± 8 tracks/cm2, within the range of uncorrected ρs values. No significant difference in ρs exists between YTT samples collected from marine and continental depositional settings. The uncorrected ρs for OTT is 1567 tracks/cm2 so that confusion with YTT is unlikely. The ρs values of the Toba tephra at Bori, Morgaon, and Gandhigram in northwestern India indicate a YTT identity, in agreement with geochemical data on their glass shards, the presence of multiple glass populations, and a glass fission-track age determination. Therefore, the view of others that OTT is present at these sites - and thereby indicates a Lower Pleistocene age for the associated Acheulean artifacts - is incorrect.

  18. 3D electromagnetic simulation of spatial autoresonance acceleration of electron beams

    NASA Astrophysics Data System (ADS)

    Dugar-Zhabon, V. D.; González, J. D.; Orozco, E. A.

    2016-02-01

    The results of full electromagnetic simulations of the electron beam acceleration by a TE 112 linear polarized electromagnetic field through Space Autoresonance Acceleration mechanism are presented. In the simulations, both the self-sustaned electric field and selfsustained magnetic field produced by the beam electrons are included into the elaborated 3D Particle in Cell code. In this system, the space profile of the magnetostatic field maintains the electron beams in the acceleration regime along their trajectories. The beam current density evolution is calculated applying the charge conservation method. The full magnetic field in the superparticle positions is found by employing the trilinear interpolation of the mesh node data. The relativistic Newton-Lorentz equation presented in the centered finite difference form is solved using the Boris algorithm that provides visualization of the beam electrons pathway and energy evolution. A comparison between the data obtained from the full electromagnetic simulations and the results derived from the motion equation depicted in an electrostatic approximation is carried out. It is found that the self-sustained magnetic field is a factor which improves the resonance phase conditions and reduces the beam energy spread.

  19. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    STS-106 Commander Terrence W. Wilcutt bends to place the STS-106 mission patch at the entrance of Atlantis in the white room of Launch Pad 39-B. Other STS-106 crew members pictured are, from left, Mission Specialists Boris V. Morukov, Yuri I. Malenchenko, Daniel C. Burbank, Pilot Scott D. Altman, Mission Specialists Richard A. Mastracchio and Edward T. Lu. Malenchenko and Morukov are with the Russian Aviation and Space Agency. The flight crew were at Kennedy Space Center to take part in Terminal Countdown Demonstration Test (TCDT) activities. The TCDT provides the crew with emergency egress training and opportunities to inspect their mission payload in the orbiter'''s payload bay. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  20. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    STS-106 Pilot Scott D. Altman, left of STS-106 Commander Terrence W. Wilcutt, answers a question during a press conference at the slide wire basket area of Launch Pad 39-B. Other crew members pictured are, from left, Mission Specialists Boris V. Morukov, Edward T. Lu, Yuri I. Malenchenko, Daniel C. Burbank and Richard A. Mastracchio. Malenchenko and Morukov are with the Russian Aviation and Space Agency. The flight crew were at Kennedy Space Center to take part in Terminal Countdown Demonstration Test (TCDT) activities. The TCDT provides the crew with emergency egress training and opportunities to inspect their mission payload in the orbiter'''s payload bay. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long- duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  1. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The STS-106 flight crew departs the Operations & Checkout Facility to take part in Terminal Countdown Demonstration Test (TCDT) activities. The TCDT provides the crew with emergency egress training and opportunities to inspect their mission payload in the orbiter'''s payload bay. Crew members taking part in the TCDT are, from left to right front to back, Commander Terrence W. Wilcutt, Pilot Scott D. Altman, Mission Specialists Yuri I. Malenchenko, Edward T. Lu, Richard A. Mastracchio, Boris V. Morukov and Daniel C. Burbank. Malenchenko and Morukov are with the Russian Aviation and Space Agency. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long- duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  2. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The STS-106 flight crew participate in a question and answer session for the media at the slide wire basket area of Launch Pad 39-B. Crew members pictured are, from left, Commander Terrence W. Wilcutt, Pilot Scott D. Altman, Mission Specialists Boris V. Morukov, Edward T. Lu, Yuri I. Malenchenko, Daniel C. Burbank and Richard A. Mastracchio. Malenchenko and Morukov are with the Russian Aviation and Space Agency. The flight crew were at Kennedy Space Center to take part in Terminal Countdown Demonstration Test (TCDT) activities. The TCDT provides the crew with emergency egress training and opportunities to inspect their mission payload in the orbiter'''s payload bay. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  3. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The STS-106 flight crew gather in the white room of Launch Pad 39-B. Crew members pictured are, from left, Mission Specialists Boris V. Morukov, Yuri I. Malenchenko, Daniel C. Burbank, Commander Terrence W. Wilcutt, Pilot Scott D. Altman, Mission Specialists Richard A. Mastracchio and Edward T. Lu. Malenchenko and Morukov are with the Russian Aviation and Space Agency. The flight crew were at Kennedy Space Center to take part in Terminal Countdown Demonstration Test (TCDT) activities. The TCDT provides the crew with emergency egress training and opportunities to inspect their mission payload in the orbiter'''s payload bay. STS- 106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  4. STS-106 crew participates in activities at Launch Pad 39-B

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The STS-106 flight crew review the slide wire basket egress system at Launch Pad 39-B. Pictured from left are Commander Terrence W. Wilcutt, Mission Specialists Boris V. Morukov, Richard A. Mastracchio, Daniel C. Burbank, Edward T. Lu, Yuri I. Malenchenko and Pilot Scott D. Altman. Malenchenko and Morukov are with the Russian Aviation and Space Agency. The flight crew were at Kennedy Space Center to take part in Terminal Countdown Demonstration Test (TCDT) activities. The TCDT provides the crew with emergency egress training and opportunities to inspect their mission payload in the orbiter'''s payload bay. STS-106 is scheduled to launch Sept. 8, 2000, at 8:31 a.m. EDT from Launch Pad 39B. On the 11-day mission, the seven-member crew will perform support tasks on orbit, transfer supplies and prepare the living quarters in the newly arrived Zvezda Service Module. The first long-duration crew, dubbed '''Expedition One,''' is due to arrive at the Station in late fall.

  5. A two-dimensional, finite-element, flux-corrected transport algorithm for the solution of gas discharge problems

    NASA Astrophysics Data System (ADS)

    Georghiou, G. E.; Morrow, R.; Metaxas, A. C.

    2000-10-01

    An improved finite-element flux-corrected transport (FE-FCT) scheme, which was demonstrated in one dimension by the authors, is now extended to two dimensions and applied to gas discharge problems. The low-order positive ripple-free scheme, required to produce a FCT algorithm, is obtained by introducing diffusion to the high-order scheme (two-step Taylor-Galerkin). A self-adjusting variable diffusion coefficient is introduced, which reduces the high-order scheme to the equivalent of the upwind difference scheme, but without the complexities of an upwind scheme in a finite-element setting. Results are presented which show that the high-order scheme reduces to the equivalent of upwinding when the new diffusion coefficient is used. The proposed FCT scheme is shown to give similar results in comparison to a finite-difference time-split FCT code developed by Boris and Book. Finally, the new method is applied for the first time to a streamer propagation problem in its two-dimensional form.

  6. Light acclimation in Porphyridium purpureum (Rhodophyta): Growth, photosynthesis, and phycobilisomes

    SciTech Connect

    Levy, I.; Gantt, E. )

    1988-12-01

    Acclimation to three photon flux densities 10, 35, 180 {mu}E{center dot}m{sup {minus}2}{center dot}s{sup {minus}1} was determined in laboratory cultures of Porphyridium purpureum Bory, Drew and Ross. Cultures grown at low, medium, and high PPFDs had compensation points of <3, 6, and 20 {mu}E{center dot}m{sup {minus}2}{center dot}s{sup {minus}1}, respectively, and saturating irradiances in the initial log phase of 90, 115, 175 {mu}E{center dot}m{sup {minus}2}{center dot}s{sup {minus}1} and up to 240 {mu}E{center dot}m{sup {minus}2}{center dot}s{sup {minus}1} in late log phase. High light cells had the smallest photosynthetic unit size (phycobiliproteins plus chlorophyll), the highest photosynthetic capacity, and the highest growth rates. Photosystem I reaction centers (P700) per cell remained proportional to chlorophyll at ca. 110 chl/P700. However, phycobiliprotein content decreased as did the phycobilisome number (ca. 50%) in high light cells, whereas the phycobilisome size remained the same as in medium and low light cells. We concluded that acclimation of this red alga to varied PPFDs was manifested by the plasticity of the photosystem II antennae with little, if any, affect noted on photosystem I.

  7. Reduction and analysis of seasons 15 and 16 (1991 - 1992) Pioneer Venus radio occulation data and correlative studies with observations of the near infrared emission of Venus

    NASA Technical Reports Server (NTRS)

    Jenkins, Jon M.

    1995-01-01

    In this study, we sought to characterize variations in the abundance and distribution of subcloud H2SO4(g) in the Venus atmosphere by using a number of 13cm radio occultation measurements conducted with the Pioneer Venus Orbiter near the inferior conjunction of 1991. A total of ten data sets were examined and analyzed, producing vertical profiles of temperature and pressure in the neutral atmosphere, and sulfuric acid vapor abundance below the main cloud layer. Two of the vertical profiles of the abundance of H2SO4(g) were correlated with NIR images of the night side of Venus made during the same period of time by Boris Ragent (under a separate PVO Guest Investigator Grant). Initially, we had hoped that the combination of these two different types of data would make it possible to constrain or identify the composition of the large particles causing the features observed in the NIR images. However, the sparseness of the radio occultation data set, combined with the sparseness of the NIR data set (one image per day over an 8 day period) made it impossible to draw strong conclusions. Considered on their own, however, the parameters retrieved from the radio occultation experiments are valuable science products.

  8. Energetic ion observations on Rhea

    NASA Astrophysics Data System (ADS)

    Kotova, A.; Roussos, E.; Krupp, N.; Dandouras, I.; Khurana, K. K.

    2012-09-01

    Cassini flew by Saturn's moon Rhea four times between 2005 and today. During two of these flybys MIMI/LEMMS energetic particle detector onboard Cassini detected significant reduction of energetic ion fluxes (20 keV - 300 keV) in vicinity of Rhea, which is probably caused by plasma absorption by the moon. The profile of the flux dropout shows differences in the different energy channels of LEMMS, primarily due to finite gyroradius effects. Other factors that contribute to the shape of the depletion profile are the properties of the background magnetospheric magnetic and electric fields, the structure of Rhea's interaction region, the ion composition and the response function of the different LEMMS channels. We will use a test-particle approach, taking into account all these factors, in order to simulate the observed depletion profiles. We will explore whether non-dipolar effects and field time variations are important in shaping the ion profile, and will also examine if LEMMS responds primarily to protons (as assumed until today) or to heavier ions. We will use several numerical techniques (e.g. fourth order Gauss Runge-Kutta and Boris particle tracking methods) and evaluate which method is the best (in terms of accuracy and computational resources) that will allow us to have good "particle statistics" and more reliable results. The same approach could be used to trace energetic charged particles and simulate observations at other Saturnian moons, such as Enceladus, Dione and Titan.

  9. Estimation of the initial amplitude of perturbation and its use in numerical simulation of plasma bubbles

    NASA Astrophysics Data System (ADS)

    Batista, Inez S.; Carrasco, Alexander J.; Abdu, Mangalathayil A.

    2012-07-01

    This work describes an experimental method for the calculation of the initial amplitude of plasma bubble seed perturbation in the bottomside F layer from ionograms. The observations show that after sunset the ionograms exhibit irregularities in the base of the F trace. In the context of the plasma depletion in the bottomside F-layer, the irregularities in ionograms can be seen like isodensity contour in evolution (in space and time). The initial amplitudes, calculated using the methodology, were used to simulate plasma bubbles through the use of flux corrected transport method with Boris-Book's flux limiter for the spatial integration and a predictor-corrector method for the direct time integration of the continuity equation of {O}^{+} and the SOR method for electric potential equation. Generalized Rayleigh-Taylor instability plays a predominant role in the evolution of long-wavelength irregularities in the equatorial ionosphere. This instability is influenced by the vertical density gradient at bottom of the F layer, and the magnitude and shape of the density perturbation that seeds the instability. The code is tested with different enhanced evening eastward electric fields to study the influences of pre-reversal enhancement in the zonal electric field on plasma bubble formation and development. The values of the zonal electric fields are based on Digisonde observations over the dip equatorial station of Cachimbo (9.5° S, 54.8° W) during the 2002 COPEX (Conjugate Point Equatorial Experiment) campaign in Brazil.

  10. Recent progress in density functional theory

    NASA Astrophysics Data System (ADS)

    Truhlar, Donald

    2014-03-01

    Ongoing work involves several areas of density functional theory: new methods for computing electronic excitation energies, including a new way to remove spin contamination in the spin-flip Tamm-Dancoff approximation and a configuration-interaction-corrected Tamm-Dancoff Approximation for treating conical intersections; new ways to treat open-shell states, including a reinterpreted broken-symmetry method and multi-configuration Kohn-Sham theory; a new exchange-correlation functional; new tests of density functional theory against databases for electronic transition energies and molecules and solids containing metal atoms; and applications. A selection of results will be presented. I am grateful to the following collaborators for contributions to the ongoing work: Boris Averkiev, Rebecca Carlson, Laura Fernandez, Laura Gagliardi, Chad Hoyer, Francesc Illas, Miho Isegawa, Shaohong Li, Giovanni Li Manni, Sijie Luo, Dongxia Ma, Remi Maurice, Rubén Means-Pañeda, Roberto Peverati, Nora Planas, Prasenjit Seal, Pragya Verma, Bo Wang, Xuefei Xu, Ke R. Yang, Haoyu Yu, Wenjing Zhang, and Jingjing Zheng. Supported in part by the AFOSR and U.S. DOE.

  11. Paring down the arsenal

    SciTech Connect

    Hippel, F. von

    1997-05-01

    The Helsinki Summit in March gave a much needed impulse-albeit a modest one-to the long-dormant nuclear arms reduction process. There had been no negotiations since the second Strategic Arms Reduction Treaty (START II) had been signed four years earlier. Although the treaty had been ratified by the US Senate, it had not been ratified by the Russian Duma, where opposition was intense. By the time the summit convened, it looked as if the treaty might simply unravel, the victim of lingering Cold War-era distrust. But President Boris Yeltsin said at the conclusion of the summit that enough progress had been made to {open_quotes}prepare grounds so that the Duma could positively look at ratifying START II.{close_quotes} That progress included a commitment by President Bill Clinton to begin negotiating a START III agreement after the Duma ratifies START II. The aim of START III, according to Clinton and Yeltsin, would be to reduce the ceiling on the number of deployed strategic warheads on each side to 2,000-2,500 by the end of the year 2007. In contrast, START II called for a limit of 3,500 deployed strategic warheads by 2003.

  12. Simulations of Dynamical Friction Including Spatially-Varying Magnetic Fields

    SciTech Connect

    Bell, G. I.; Bruhwiler, D. L.; Busby, R.; Abell, D. T.; Messmer, P.; Veitzer, S.; Litvinenko, V. N.; Cary, J. R.

    2006-03-20

    A proposed luminosity upgrade to the Relativistic Heavy Ion Collider (RHIC) includes a novel electron cooling section, which would use {approx}55 MeV electrons to cool fully-ionized 100 GeV/nucleon gold ions. We consider the dynamical friction force exerted on individual ions due to a relevant electron distribution. The electrons may be focussed by a strong solenoid field, with sensitive dependence on errors, or by a wiggler field. In the rest frame of the relativistic co-propagating electron and ion beams, where the friction force can be simulated for nonrelativistic motion and electrostatic fields, the Lorentz transform of these spatially-varying magnetic fields includes strong, rapidly-varying electric fields. Previous friction force simulations for unmagnetized electrons or error-free solenoids used a 4th-order Hermite algorithm, which is not well-suited for the inclusion of strong, rapidly-varying external fields. We present here a new algorithm for friction force simulations, using an exact two-body collision model to accurately resolve close interactions between electron/ion pairs. This field-free binary-collision model is combined with a modified Boris push, using an operator-splitting approach, to include the effects of external fields. The algorithm has been implemented in the VORPAL code and successfully benchmarked.

  13. Remote sensing of hydrologic variables in boreal areas

    NASA Technical Reports Server (NTRS)

    Peck, Eugene L.; Carroll, Thomas R.

    1995-01-01

    During Phase 2 airborne Gamma Radiation measurements were conducted over 48 BOREAS flight lines. Ground measurements of the soil moisture (SM) of the mineral soil and of the depth and water content (WC) of the moss/humus layer were collected for calibration of the flight lines. Special attention has been given to the flight lines over and near the primary tower sites in the southern study area (SSA): Old Black Spruce (OBS), Old Jack Pine, Old Aspen, and Young Aspen. Multiple ground surveys (September 1993; July, August, and September 1994) show the variation of the water content of the moss/humus layers and changes in the amount of standing water near the SSA, OBS tower during the period September 1993 to September 1994. All ground data, airborne estimates and locations of flight lines and ground sampling points have been submitted to BORIS (Boreas Information System). On 8-10 September 1994 exceptionally high values of cosmic radiation were observed by the airborne gamma radiation system over the SSA. Follow-up investigation has not determined the source of, or what caused, the high cosmic count rates.

  14. Remote sensing of hydrologic variables in boreal areas, phase 2

    NASA Technical Reports Server (NTRS)

    Peck, Eugene L.; Carroll, Thomas R.

    1995-01-01

    During Phase 2 airborne Gamma Radiation measurements were conducted over 48 BOREAS (boreal ecosystem atmosphere study) flight lines. Ground measurements of the soil moisture (SM) of the mineral soil and the depth and water content (WC) of the moss/humus layer were collected for calibration of the flight lines. Special attention has been given to the flight lines over, and near, the primary tower sites in the southern study area (SSA); Old Black Spruce (OBS), Old Jack Pine, Old Aspen, and Young Aspen. Multiple ground surveys (September 1993, July, August, and September 1994) show the variation of the water content of the moss/humus layers and changes in the amount of standing water near the SSA OBS tower during the period September 1993 to September 1994. All ground data, airborne estimates and locations of flight lines and ground sampling points have been submitted to BORIS (BOREAS Information System). On 8-10 September 1994 exceptionally high values of cosmic radiation were observed by the airborne gamma radiation system over the SSA. Follow up investigation has not determined the source of, or what caused, the high cosmic count rates.

  15. Reintroduction of the European Capercaillie from the Capercaillie Breeding Centre in Wisła Forest District: Genetic Assessments of Captive and Reintroduced Populations

    PubMed Central

    Strzała, Tomasz; Kowalczyk, Artur; Łukaszewicz, Ewa

    2015-01-01

    The Western capercaillie (Tetrao urogallus) is a specific bird species, which, despite its very broad distribution and large global population size, is highly endangered in many Western and Central European countries. According to the species situation, in many countries (including Poland), breeding and reintroduction programmes have been started. One of the most complex and large-scale reintroduction programmes was started in Bory Dolnośląskie Forest, and the Capercaillie Breeding Centre in Wisła Forest District was used as one of the sources of individuals for reintroduction. As genetic tools provide essential knowledge about species biodiversity, which is crucially important during the breeding process and reintroduction, both captive and reintroduced grouse populations were genetically analysed. We were particularly interested in genetic diversity of the individuals in both populations and the genetic relationship between them, as well as between them and other capercaillie representatives from their current range. To fulfil these goals we determined nine microsatellite loci along with a fragment of the mitochondrial control region. Genetic diversity parameters were moderate to high compared to populations from other Central and Western European countries. Both populations were clustered into three distinct genetic clades based on microsatellites. Phylogenetic analysis placed all mitochondrial haplotypes we revealed in the Eurasian clade. The present results will play an important role as they will help to preserve and maximize genetic diversity in captive populations, and will provide a basis for future monitoring of the reintroduction process. PMID:26682897

  16. Explicit time-reversible orbit integration in Particle In Cell codes with static homogeneous magnetic field

    NASA Astrophysics Data System (ADS)

    Patacchini, L.; Hutchinson, I. H.

    2009-04-01

    A new explicit time-reversible orbit integrator for the equations of motion in a static homogeneous magnetic field - called Cyclotronic integrator - is presented. Like Spreiter and Walter's Taylor expansion algorithm, for sufficiently weak electric field gradients this second order method does not require a fine resolution of the Larmor motion; it has however the essential advantage of being symplectic, hence time-reversible. The Cyclotronic integrator is only subject to a linear stability constraint ( ΩΔ t < π, Ω being the Larmor angular frequency), and is therefore particularly suitable to electrostatic Particle In Cell codes with uniform magnetic field where Ω is larger than any other characteristic frequency, yet a resolution of the particles' gyromotion is required. Application examples and a detailed comparison with the well-known (time-reversible) Boris algorithm are presented; it is in particular shown that implementation of the Cyclotronic integrator in the kinetic codes SCEPTIC and Democritus can reduce the cost of orbit integration by up to a factor of ten.

  17. Effect of dietary karaya saponin on serum and egg yolk cholesterol in laying hens.

    PubMed

    Afrose, S; Hossain, M S; Tsujii, H

    2010-12-01

    1. The objective of the study was to investigate the effect of dietary karaya saponin on cholesterol deposition in laying hens. 2. A total of 40 Boris Brown hens were randomly assigned at 20 weeks of age to 4 treatment groups and fed on diets supplemented with 0 (control), 25, 50 or 75 mg/kg karaya saponin for an 8-week experimental period. 3. After 8 weeks of dietary supplementation, karaya-saponin-treated groups had significantly lower serum cholesterol (23·0%) and triglycerides but increased high density lipoproteins cholesterol concentration than controls, irrespective of karaya saponin content in the diet. Egg yolk cholesterol and triglycerides were also significantly reduced by dietary karaya saponin. Hepatic cholesterol and triglycerides were significantly reduced by karaya saponin but bile acids concentration in the faeces and liver were significantly increased by karaya saponin. The concentrations of oleic, linoleic and linolenic acids in the yolk were greater in hens receiving karaya saponin than in controls. Karaya saponin significantly increased egg production, feed efficiency and yolk colour compared with controls. Karaya saponin tended to increase egg weight, feed consumption, Haugh units, albumen weight and yolk index. 4. In conclusion, karaya saponin is a potential agent for reducing yolk cholesterol concentration together with an overall increase of production performance and improvement in egg quality. PMID:21161787

  18. COMMITTEES: SQM 2007 - International Conference On Strangeness In Quark Matter SQM 2007 - International Conference On Strangeness In Quark Matter

    NASA Astrophysics Data System (ADS)

    2008-04-01

    Local Organising Committee Ivan Králik (IEP SAS, Košice) Vojtěch Petráček (Czechoslovakia Technical University, Prague) Ján Pišút (Comenius University, Bratislava) Emanuele Quercigh (CERN) Karel Šafařík (CERN), Co-chair Ladislav v Sándor (IEP SAS, Košice), Co-chair Boris Tomášik (Mateja Bela University, Banská Bystrica) Jozef Urbán (UPJŠ Košice) International Advisory Committee Jörg Aichelin, Nantes Federico Antinori, Padova Tamás Biró, Budapest Peter Braun-Munzinger, GSI Jean Cleymans, Cape Town László Csernai, Bergen Timothy Hallman, BNL Huan Zhong Huang, UCLA Sonja Kabana, Nantes Roy A Lacey, Stony Brook Carlos Lourenço, CERN Yu-Gang Ma, Shanghai Jes Masden, Aarhus Yasuo Miake, Tsukuba Berndt Müller, Duke Grazyna Odyniec, LBNL Helmut Oeschler, Darmstadt Jan Rafelski, Arizona Hans Georg Ritter, LBNL Jack Sandweiss, Yale George S F Stephans, MIT Horst Stöcker, Frankfurt Thomas Ullrich, BNL Orlando Villalobos-Baillie, Birmingham William A Zajc, Columbia

  19. BOREAS RSS-14 Level 1a GOES-7 Visible, IR, and Water Vapor Images

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Newcomer, Jeffrey A.; Faysash, David; Cooper, Harry J.; Smith, Eric A.

    2000-01-01

    The BOREAS RSS-14 team collected and processed GOES-7 and -8 images of the BOREAS region as part of its effort to characterize the incoming, reflected, and emitted radiation at regional scales. The level-1a BOREAS GOES-7 image data were collected by RSS-14 personnel at FSU and processed to level-1a products by BORIS personnel. The data cover the period of 01-Jan-1994 through 08-Jul-1995 with partial to complete coverage on the majority of the days. The data include three bands with eightbit pixel values. No major problems with the data have been identified. Due to the large size of the images, the level-1a GOES-7 data are not contained on the BOREAS CD-ROM set. An inventory listing file is supplied on the CD-ROM to inform users of what data were collected. The level-1a GOES-7 image data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). See sections 15 and 16 for more information. The data files are available on a CD-ROM (see document number 20010000884).

  20. BOREAS Hardcopy Maps

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Nelson, Elizabeth; Newcomer, Jeffrey A.

    2000-01-01

    Boreal Ecosystem-Atmospheric Study (BOREAS) hardcopy maps are a collection of approximately 1,000 hardcopy maps representing the physical, climatological, and historical attributes of areas covering primarily the Manitoba and Saskatchewan provinces of Canada. These maps were collected by BOREAS Information System (BORIS) and Canada for Remote Sensing (CCRS) staff to provide basic information about site positions, manmade features, topography, geology, hydrology, land cover types, fire history, climate, and soils of the BOREAS study region. These maps are not available for distribution through the BOREAS project but may be used as an on-site resource. Information is provided within this document for individuals who want to order copies of these maps from the original map source. Note that the maps are not contained on the BOREAS CD-ROM set. An inventory listing file is supplied on the CD-ROM to inform users of the maps that are available. This inventory listing is available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). For hardcopies of the individual maps, contact the sources provided.

  1. BOREAS Level-3s SPOT Imagery: Scaled At-sensor Radiance in LGSOWG Format

    NASA Technical Reports Server (NTRS)

    Strub, Richard; Nickeson, Jaime; Newcomer, Jeffrey A.; Hall, Forrest G. (Editor); Cihlar, Josef

    2000-01-01

    For BOReal Ecosystem-Atmosphere Study (BOREAS), the level-3s Satellite Pour l'Observation de la Terre (SPOT) data, along with the other remotely sensed images, were collected in order to provide spatially extensive information over the primary study areas. This information includes radiant energy, detailed land cover, and biophysical parameter maps such as Fraction of Photosynthetically Active Radiation (FPAR) and Leaf Area Index (LAI). The SPOT images acquired for the BOREAS project were selected primarily to fill temporal gaps in the Landsat Thematic Mapper (TM) image data collection. CCRS collected and supplied the level-3s images to BOREAS Information System (BORIS) for use in the remote sensing research activities. Spatially, the level-3s images cover 60- by 60-km portions of the BOREAS Northern Study Area (NSA) and Southern Study Area (SSA). Temporally, the images cover the period of 17-Apr-1994 to 30-Aug-1996. The images are available in binary image format files. Due to copyright issues, the SPOT images may not be publicly available.

  2. BOREAS RSS-14 Level-1 GOES-7 Visible, IR and Water Vapor Images

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Faysash, David; Cooper, Harry J.; Smith, Eric A.; Newcomer, Jeffrey A.

    2000-01-01

    The BOREAS RSS-14 team collected and processed GOES-7 and -8 images of the BOREAS region as part of its effort to characterize the incoming, reflected, and emitted radiation at regional scales. The level-1 BOREAS GOES-7 image data were collected by RSS-14 personnel at FSU and delivered to BORIS. The data cover the period of 01-Jan-1994 through 08-Jul-1995, with partial to complete coverage on the majority of the days. The data include three bands with eight-bit pixel values. No major problems with the data have been identified. Due to the large size of the images, the level-1 GOES-7 data are not contained on the BOREAS CD-ROM set. An inventory listing file is supplied on the CD-ROM to inform users of what data were collected. The level-1 GOES-7 image data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). See sections 15 and 16 for more information. The data files are available on a CD-ROM (see document number 20010000884).

  3. BOREAS RSS-14 Level-1 GOES-8 Visible, IR and Water Vapor Images

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Faysash, David; Cooper, Harry J.; Smith, Eric A.; Newcomer, Jeffrey A.

    2000-01-01

    The BOREAS RSS-14 team collected and processed several GOES-7 and GOES-8 image data sets that covered the BOREAS study region. The level-1 BOREAS GOES-8 images are raw data values collected by RSS-14 personnel at FSU and delivered to BORIS. The data cover 14-Jul-1995 to 21-Sep-1995 and 01-Jan-1996 to 03-Oct-1996. The data start out containing three 8-bit spectral bands and end up containing five 10-bit spectral bands. No major problems with the data have been identified. The data are contained in binary image format files. Due to the large size of the images, the level-1 GOES-8 data are not contained on the BOREAS CD-ROM set. An inventory listing file is supplied on the CD-ROM to inform users of what data were collected. The level-1 GOES-8 image data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). See sections 15 and 16 for more information. The data files are available on a CD-ROM (see document number 20010000884).

  4. BOREAS HYD-2 Estimated Snow Water Equivalent (SWE) from Microwave Measurements

    NASA Technical Reports Server (NTRS)

    Powell, Hugh; Chang, Alfred T. C.; Hall, Forrest G. (Editor); Knapp, David E. (Editor); Smith, David E. (Technical Monitor)

    2000-01-01

    The surface meteorological data collected at the Boreal Ecosystem-Atmosphere Study (BOREAS) tower and ancillary sites are being used as inputs to an energy balance model to monitor the amount of snow storage in the boreal forest region. The BOREAS Hydrology (HYD)-2 team used Snow Water Equivalent (SWE) derived from an energy balance model and in situ observed SWE to compare the SWE inferred from airborne and spaceborne microwave data, and to assess the accuracy of microwave retrieval algorithms. The major external measurements that are needed are snowpack temperature profiles, in situ snow areal extent, and SWE data. The data in this data set were collected during February 1994 and cover portions of the Southern Study Area (SSA), Northern Study Area (NSA), and the transect areas. The data are available from BORIS as comma-delimited tabular ASCII files. The SWE data are available from the Earth Observing System Data and Information System (EOSDIS) Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC). The data files are available on a CD-ROM (see document number 20010000884).

  5. Contemporary particle-in-cell approach to laser-plasma modelling

    NASA Astrophysics Data System (ADS)

    Arber, T. D.; Bennett, K.; Brady, C. S.; Lawrence-Douglas, A.; Ramsay, M. G.; Sircombe, N. J.; Gillies, P.; Evans, R. G.; Schmitz, H.; Bell, A. R.; Ridgers, C. P.

    2015-11-01

    Particle-in-cell (PIC) methods have a long history in the study of laser-plasma interactions. Early electromagnetic codes used the Yee staggered grid for field variables combined with a leapfrog EM-field update and the Boris algorithm for particle pushing. The general properties of such schemes are well documented. Modern PIC codes tend to add to these high-order shape functions for particles, Poisson preserving field updates, collisions, ionisation, a hybrid scheme for solid density and high-field QED effects. In addition to these physics packages, the increase in computing power now allows simulations with real mass ratios, full 3D dynamics and multi-speckle interaction. This paper presents a review of the core algorithms used in current laser-plasma specific PIC codes. Also reported are estimates of self-heating rates, convergence of collisional routines and test of ionisation models which are not readily available elsewhere. Having reviewed the status of PIC algorithms we present a summary of recent applications of such codes in laser-plasma physics, concentrating on SRS, short-pulse laser-solid interactions, fast-electron transport, and QED effects.

  6. Large-timestep mover for particle simulations of arbitrarilymagnetized species

    SciTech Connect

    Cohen, R.H.; Friedman, A.; Grote, D.P.; Vay, J-L.

    2007-03-26

    For self-consistent ion-beam simulations including electron motion, it is desirable to be able to follow electron dynamics accurately without being constrained by the electron cyclotron timescale. To this end, we have developed a particle-advance that interpolates between full particle dynamics and drift motion. By making a proper choice of interpolation parameter, simulation particles experience physically correct parallel dynamics, drift motion, and gyroradius when the timestep is large compared to the cyclotron period, though the effective gyro frequency is artificially low; in the opposite timestep limit, the method approaches a conventional Boris particle push. By combining this scheme with a Poisson solver that includes an interpolated form of the polarization drift in the dielectric response, the movers utility can be extended to higher-density problems where the plasma frequency of the species being advanced exceeds its cyclotron frequency. We describe a series of tests of the mover and its application to simulation of electron clouds in heavy-ion accelerators.

  7. Large-Timestep Mover for Particle Simulations of Arbitrarily Magnetized Species

    SciTech Connect

    Cohen, R H; Friedman, A; Grote, D P; Vay, J

    2006-06-16

    For self-consistent ion-beam simulations including electron motion, it is desirable to be able to follow electron dynamics accurately without being constrained by the electron cyclotron timescale. To this end, we have developed a particle-advance that interpolates between full particle dynamics and drift motion. By making a proper choice of interpolation parameter, simulation particles experience physically correct parallel dynamics, drift motion, and gyroradius when the timestep is large compared to the cyclotron period, though the effective gyro frequency is artificially low; in the opposite timestep limit, the method approaches a conventional Boris particle push. By combining this scheme with a Poisson solver that includes an interpolated form of the polarization drift in the dielectric response, the movers utility can be extended to higher-density problems where the plasma frequency of the species being advanced exceeds its cyclotron frequency. We describe a series of tests of the mover and its application to simulation of electron clouds in heavy-ion accelerators.

  8. The endocrine quiz

    PubMed Central

    Kalra, Sanjay; Baruah, Manash P.; Nagesh, V. Sri

    2014-01-01

    With the recent explosion in endocrine conferences, audience fatigue has set in and conference planners are now looking at newer pedagogic methods to revive the interest of audiences in these conferences. The endocrine quiz has finally come of vogue and is increasingly becoming one of the most popular attractions of any ranking endocrine conference. The endocrine quiz has a large and varied palette and draws questions from religious scriptures, history, literature, current affairs, sports, movies and basic and paramedical sciences. The more we delve into the quizzable aspects of endocrinology, the more we realize that endocrinology is ubiquitous and there is no sphere in human life untouched by endocrine disorders. Be it epic characters like Kumbhakarna and Bheema, fiction characters like Tintin or Orphan Annie, sportspersons like Gail Devers or heads of state like George Bush Sr and Boris Yeltsin, all have contributed to the melting pot of endocrine quizzing. Adding further grist to the endocrine mill are the Nobel prizes, with their attendant anecdotes and controversies. Step into this world of endocrine quizzing to have an up close and personal look at the diverse facets of this subject. PMID:24944922

  9. Measuring time of flight of fusion products in an inertial electrostatic confinement fusion device for spatial profiling of fusion reactions

    SciTech Connect

    Donovan, D. C.; Boris, D. R.; Kulcinski, G. L.; Santarius, J. F.; Piefer, G. R.

    2013-03-15

    A new diagnostic has been developed that uses the time of flight (TOF) of the products from a nuclear fusion reaction to determine the location where the fusion reaction occurred. The TOF diagnostic uses charged particle detectors on opposing sides of the inertial electrostatic confinement (IEC) device that are coupled to high resolution timing electronics to measure the spatial profile of fusion reactions occurring between the two charged particle detectors. This diagnostic was constructed and tested by the University of Wisconsin-Madison Inertial Electrostatic Confinement Fusion Group in the IEC device, HOMER, which accelerates deuterium ions to fusion relevant energies in a high voltage ({approx}100 kV), spherically symmetric, electrostatic potential well [J. F. Santarius, G. L. Kulcinski, R. P. Ashley, D. R. Boris, B. B. Cipiti, S. K. Murali, G. R. Piefer, R. F. Radel, T. E. Radel, and A. L. Wehmeyer, Fusion Sci. Technol. 47, 1238 (2005)]. The TOF diagnostic detects the products of D(d,p)T reactions and determines where along a chord through the device the fusion event occurred. The diagnostic is also capable of using charged particle spectroscopy to determine the Doppler shift imparted to the fusion products by the center of mass energy of the fusion reactants. The TOF diagnostic is thus able to collect spatial profiles of the fusion reaction density along a chord through the device, coupled with the center of mass energy of the reactions occurring at each location. This provides levels of diagnostic detail never before achieved on an IEC device.

  10. Molecular Types of Methicillin-Resistant Staphylococcus aureus and Methicillin-Sensitive S. aureus Strains Causing Skin and Soft Tissue Infections and Nasal Colonization, Identified in Community Health Centers in New York City

    PubMed Central

    Pardos de la Gandara, Maria; Raygoza Garay, Juan Antonio; Mwangi, Michael; Tobin, Jonathan N.; Tsang, Amanda; Khalida, Chamanara; D'Orazio, Brianna; Kost, Rhonda G.; Leinberger-Jabari, Andrea; Coffran, Cameron; Evering, Teresa H.; Coller, Barry S.; Balachandra, Shirish; Urban, Tracie; Parola, Claude; Salvato, Scott; Jenks, Nancy; Wu, Daren; Burgess, Rhonda; Chung, Marilyn; de Lencastre, Herminia

    2015-01-01

    In November 2011, The Rockefeller University Center for Clinical and Translational Science (CCTS), the Laboratory of Microbiology and Infectious Diseases, and Clinical Directors Network (CDN) launched a research and learning collaborative project with six community health centers in the New York City metropolitan area to determine the nature (clonal type) of community-acquired Staphylococcus aureus strains causing skin and soft tissue infections (SSTIs). Between November 2011 and March 2013, wound and nasal samples from 129 patients with active SSTIs suspicious for S. aureus were collected and characterized by molecular typing techniques. In 63 of 129 patients, the skin wounds were infected by S. aureus: methicillin-resistant S. aureus (MRSA) was recovered from 39 wounds and methicillin-sensitive S. aureus (MSSA) was recovered from 24. Most—46 of the 63–wound isolates belonged to the CC8/Panton-Valentine leukocidin-positive (PVL+) group of S. aureus clone USA300: 34 of these strains were MRSA and 12 were MSSA. Of the 63 patients with S. aureus infections, 30 were also colonized by S. aureus in the nares: 16 of the colonizing isolates were MRSA, and 14 were MSSA, and the majority of the colonizing isolates belonged to the USA300 clonal group. In most cases (70%), the colonizing isolate belonged to the same clonal type as the strain involved with the infection. In three of the patients, the identity of invasive and colonizing MRSA isolates was further documented by whole-genome sequencing. PMID:26063853

  11. Prevalence and characteristics of meticillin-resistant Staphylococcus aureus in humans in contact with farm animals, in livestock, and in food of animal origin, Switzerland, 2009.

    PubMed

    Huber, H; Koller, S; Giezendanner, N; Stephan, R; Zweifel, C

    2010-04-22

    A total of 2,662 samples, collected from March to September 2009 in Switzerland, were tested for the presence of meticillin-resistant Staphylococcus aureus (MRSA). The collection comprised nasal swabs from 148 pig farmers, 133 veterinarians, 179 slaughterhouse employees, 800 pigs, 300 calves, 400 cattle, 100 pooled neck skin swabs from chicken carcasses, and 460 food samples of animal origin. Moreover, 142 S. aureus strains, isolated from bovine mastitis milk, were included in the study. Twenty samples (< 1%; four veterinarians, 10 pigs, three calves, one young bull, and two mastitis milk samples) tested positive for MRSA. Genotyping of the MRSA strains was performed by multilocus sequence typing, spa- and SCCmec-typing, and revealed ST398 (n=18), ST8 (n=1), ST 1 (n=1), spa types t011 (n=7), t034 (n=11), t064 (n=1), t127 (n=1), and SCCmec types IV (n=4) and V (n=16). The 20 MRSA strains were subjected to antibiotic susceptibility testing and pulsed-field gel electrophoresis using the restriction enzyme EagI. Supplementary PCR reactions were performed to investigate the presence of Panton-Valentine leukocidin and staphylococcal enterotoxins A to D. PMID:20430001

  12. Prevalence and clonality of methicillin-resistant Staphylococcus aureus (MRSA) in the Atlantic Azores islands: predominance of SCCmec types IV, V and VI.

    PubMed

    Conceição, T; Tavares, A; Miragaia, M; Hyde, K; Aires-de-Sousa, M; de Lencastre, H

    2010-05-01

    In order to obtain insights into the methicillin-resistant Staphylococcus aureus (MRSA) population structure in the Azores archipelago, 106 MRSA isolates were collected from patients attending an Azorean central hospital between January 2007 and February 2008. Antimicrobial resistance was determined for all isolates. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE), spa typing, multilocus sequence typing (MLST), staphylococcal chromosome cassette mec (SCCmec) typing and the presence of Panton-Valentine leukocidin (PVL). The majority of the isolates (87%, n = 92) belonged to the EMRSA-15 clone (ST22, SCCmec-IVh), followed by the Pediatric clone (ST5-VI/IVc) (11%, n = 12). The Berlin clone (ST45-IVa) and a new clone (spa type t1839, ST1339 and SCCmec V variant) were represented by single isolates. All of the isolates carried SCCmec types IV, V or VI and a non-multiresistant antibiotic profile, resembling the currently emerging community MRSA. Moreover, PVL was described for the first time to be associated with the Pediatric clone carrying SCCmec type VI. We provided the first description of the population structure of MRSA in the Azores islands, which seems to be shaped by genetic events occurring locally, as well as by the regular population exchange between the islands, continental Portugal, the United Kingdom and the United States. PMID:20229224

  13. [Community associated-methicillin-resistant Staphylococcus aureus (SAMR-AC): comunication of the first four pediatric cases in the Roberto del Rio Children's Hospital].

    PubMed

    Acuña, Mirta; Benadof, Dona; Jadue, Carla; Hormazábal, Juan C; Alarcón, Pedro; Contreras, Julio; Torres, Ramón; Mülchi, Cristóbal; Aguayo, Carolina; Fernández, Jorge; Araya, Pamela

    2015-06-01

    Staphylococcus aureus is a known pathogen in pediatric patients that produces skin infections, cutaneous abscess, cellulitis and osteoarticular infections. Most of these infections are produced by a meticilin susceptible strain. The community associated methicillin resistant Staphylococcus aureus was published for the first time in 1993, ever since then is has been recognized as a cosmopolite pathogen. The first report in Latin America was published in 2003, and in Chile in 2008 from adult patients that have reported traveling to other countries. The following series describes four pediatric cases, all school-aged children, diagnosed since 2012 with clinical followups and molecular studies. Two cases presented as osteomyelitis of the lower extremity; and one presented as arm cellulitis. These three cases had Panton Valentine leukocidine (PV-L) negative strains from the clone complex 8. The last case presented a renal abscess, the strain was PV-L positive from the clone complex 30. This case series constitutes the first pediatric case report in Chile. PMID:26230445

  14. Methicillin-resistant Staphylococcus aureus ST30-SCCmec IVc clone as the major cause of community-acquired invasive infections in Argentina.

    PubMed

    Fernandez, S; de Vedia, L; Lopez Furst, M J; Gardella, N; Di Gregorio, S; Ganaha, M C; Prieto, S; Carbone, E; Lista, N; Rotrying, F; Stryjewski, M E; Mollerach, M

    2013-03-01

    Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections have become a major concern worldwide. We conducted a prospective multicenter study of invasive CA-MRSA to evaluate clinical features and genotype of strains causing invasive infections in Argentina. A total of 55 patients with invasive CA-MRSA infections were included. Most patients (60%) had bloodstream infections, 42% required admission to intensive care unit and 16% died. No CA-MRSA isolates were multiresistant (resistant ⩾3 classes of antibiotics). All isolates carried Panton-Valentine leukocidin (PVL) genes and staphylococcal cassette chromosome (SCCmec) type IV. The majority CA-MRSA strains belonged to ST30 and had identical pulsed-field gel electrophoresis (PFGE) patterns, qualifying as a clonal dissemination of a highly transmissible strain. The main clone recovered from patients with CA-MRSA invasive infections was genotyped as pulsed-field gel electrophoresis type C-ST30, SCCmec type IVc-spa type 019, PVL positive. It has become predominant and replaced the previously described CA-MRSA clone (PFGE type A, ST5, SCCmec type IV, spa type 311). PMID:23340226

  15. The δ Subunit of RNA Polymerase Guides Promoter Selectivity and Virulence in Staphylococcus aureus

    PubMed Central

    Weiss, Andy; Ibarra, J. Antonio; Paoletti, Jessica; Carroll, Ronan K.

    2014-01-01

    In Gram-positive bacteria, and particularly the Firmicutes, the DNA-dependent RNA polymerase (RNAP) complex contains an additional subunit, termed the δ factor, or RpoE. This enigmatic protein has been studied for more than 30 years for various organisms, but its function is still not well understood. In this study, we investigated its role in the major human pathogen Staphylococcus aureus. We showed conservation of important structural regions of RpoE in S. aureus and other species and demonstrated binding to core RNAP that is mediated by the β and/or β′ subunits. To identify the impact of the δ subunit on transcription, we performed transcriptome sequencing (RNA-seq) analysis and observed 191 differentially expressed genes in the rpoE mutant. Ontological analysis revealed, quite strikingly, that many of the downregulated genes were known virulence factors, while several mobile genetic elements (SaPI5 and prophage ϕSA3usa) were strongly upregulated. Phenotypically, the rpoE mutant had decreased accumulation and/or activity of a number of key virulence factors, including alpha toxin, secreted proteases, and Panton-Valentine leukocidin (PVL). We further observed significantly decreased survival of the mutant in whole human blood, increased phagocytosis by human leukocytes, and impaired virulence in a murine model of infection. Collectively, our results demonstrate that the δ subunit of RNAP is a critical component of the S. aureus transcription machinery and plays an important role during infection. PMID:24491578

  16. Population Structure of Staphylococcus aureus from Trinidad & Tobago

    PubMed Central

    Monecke, Stefan; Stieber, Bettina; Roberts, Rashida; Akpaka, Patrick Eberechi; Slickers, Peter; Ehricht, Ralf

    2014-01-01

    It has been shown previously that high rates of methicillin- and mupirocin-resistant Staphylococcus aureus exist in the Caribbean islands of Trinidad and Tobago, as well as a high prevalence of Panton-Valentine leukocidin-positive S. aureus. Beyond these studies, limited typing data have been published. In order to obtain insight into the population structure not only of MRSA but also of methicillin-susceptible S. aureus, 294 clinical isolates collected in 2012/2013 were typed by microarray hybridisation. A total of 15.31% of the tested isolates were MRSA and 50.00% were PVL-positive. The most common MSSA strains were PVL-positive CC8-MSSA (20.41% of all isolates tested), PVL-positive CC152-MSSA (9.52%) and PVL-positive CC30-MSSA (8.84%) while the most common MRSA were ST239-MRSA-III&SCCmer (9.18%) and ST8-MRSA-IV, “USA300” (5.78%). 2.38% of characterised isolates belonged to distinct strains likely to be related to “Staphylococcus argenteus” lineages. The population structure of S. aureus isolates suggests an importation of strains from Africa, endemicity of PVL-positive MSSA (mainly CC8) and of ST239-MRSA-III, and a recent emergence of the PVL-positive CC8-MRSA-IV strain “USA300”. PMID:24586536

  17. Hyphal tip extension in Aspergillus nidulans requires the manA gene, which encodes phosphomannose isomerase.

    PubMed Central

    Smith, D J; Payton, M A

    1994-01-01

    A strain of Aspergillus nidulans carrying a temperature-sensitive mutation in the manA gene produces cell walls depleted of D-mannose and forms hyphal tip balloons at the restrictive temperature (B.P. Valentine and B.W. Bainbridge, J. Gen. Microbiol. 109:155-168, 1978). We have isolated and characterized the manA gene and physically located it between 3.5 and 5.5 kb centromere distal of the riboB locus on chromosome VIII. The manA gene contains four introns and encodes a 50.6-kDa protein which has significant sequence identity to type I phosphomannose isomerase proteins from other eukaryotes. We have constructed by integrative transformation a null mutation in the manA gene which can only be maintained in a heterokaryotic strain with wild-type manA+ nuclei. Thus, a manA null mutation is lethal in A. nidulans. The phenotype of the mutation was analyzed in germinating conidia. Such conidia are able to commence germination but swell abnormally, sometimes producing a misshapen germ tube, before growth ceases. The reason for the lethality is probably the lack of synthesis of mannose-containing cell wall polymers that must be required for normal cell wall development in growing hyphae. Images PMID:8065336

  18. Methicillin-resistant Staphylococcus aureus in Horses and Horse Personnel, 2000–2002

    PubMed Central

    Archambault, M.; Dick, H.; Hearn, P.; Kreiswirth, B.N.; Said-Salim, B.; McGeer, A.; Likhoshvay, Y.; Prescott, J.F.; Low, D.E.

    2005-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infection was identified in 2 horses treated at a veterinary hospital in 2000, prompting a study of colonization rates of horses and associated persons. Seventy-nine horses and 27 persons colonized or infected with MRSA were identified from October 2000 to November 2002; most isolations occurred in a 3-month period in 2002. Twenty-seven (34%) of the equine isolates were from the veterinary hospital, while 41 (51%) were from 1 thoroughbred farm in Ontario. Seventeen (63%) of 27 human isolates were from the veterinary hospital, and 8 (30%) were from the thoroughbred farm. Thirteen (16%) horses and 1 (4%) person were clinically infected. Ninety-six percent of equine and 93% of human isolates were subtypes of Canadian epidemic MRSA-5, spa type 7 and possessed SCCmecIV. All tested isolates from clinical infections were negative for the Panton-Valentine leukocidin genes. Equine MRSA infection may be an important emerging zoonotic and veterinary disease. PMID:15757559

  19. Resistance profiles in surgical-site infection.

    PubMed

    Lenz, Andreas M; Fairweather, Mark; Cheadle, William G

    2008-08-01

    Surgical-site infections (SSIs) remain a common complication, affecting some 5% of patients undergoing surgical procedures and can sometimes present a major challenge after surgery with life-threatening septic illness. The appearance of organisms that are often resistant to common antibiotic treatment is of great concern. Staphylococcus aureus is the organism most commonly recovered from infected surgical wounds, and usually contaminates wounds from the patients own skin. SSIs occur despite appropriate skin disinfection, sterilization of instruments, use of gown and gloves, appropriate sterile technique and prophylactic antimicrobials. In fact, it is difficult to maintain a sterile field over time, and most wounds become contaminated throughout the course of surgery. Methicillin-resistant S. aureus (MRSA) first arose in the hospital setting, but have more recently evolved in the community. Such community-acquired MRSA are genetically different and seem to be even more virulent owing to genes that encode virulence factors, such as staphylococcal cassette chromosome mec type IV and Panton-Valentine leukocidin. The purpose of this review is to summarize characteristics of frequently isolated bacterial strains from SSIs. The focus will be on Gram-positive organisms because of their increasing prevalence in SSIs and their high potential to develop resistance against several antibiotic agents, including vancomycin. PMID:18651816

  20. Mass Spectrometry and Multiplex Antigen Assays to Assess Microbial Quality and Toxin Production of Staphylococcus aureus Strains Isolated from Clinical and Food Samples

    PubMed Central

    Attien, Paul; Sina, Haziz; Moussaoui, Wardi; Zimmermann-Meisse, Gaëlle; Dadié, Thomas; Keller, Daniel; Riegel, Philippe; Edoh, Vincent; Kotchoni, Simeon O.; Djè, Marcellin; Prévost, Gilles

    2014-01-01

    The aim of our study was to investigate the microbial quality of meat products and on some clinical samples in Abidjan focused on Staphylococcus genus and the toxin production profile of Staphylococcus aureus (S. aureus) isolated. Bacteria were collected from 240 samples of three meat products sold in Abidjan and 180 samples issued from clinical infections. The strains were identified by both microbiological and MALDI-TOF-MS methods. The susceptibility to antibiotics was determined by the disc diffusion method. The production of Panton-Valentine Leukocidin, LukE/D, and epidermolysins was screened using radial gel immunodiffusion. The production of staphylococcal enterotoxins and TSST-1 was screened by a Bio-Plex Assay. We observed that 96/240 of meat samples and 32/180 of clinical samples were contaminated by Staphylococcus. Eleven species were isolated from meats and 4 from clinical samples. Forty-two S. aureus strains were isolated from ours samples. Variability of resistance was observed for most of the tested antibiotics but none of the strains displays a resistance to imipenem and quinolones. We observed that 89% of clinical S. aureus were resistant to methicillin against 58% for those issued from meat products. All S. aureus isolates issued from meat products produce epidermolysins whereas none of the clinical strains produced these toxins. The enterotoxins were variably produced by both clinical and meat product samples. PMID:24987686

  1. Why Do People Tend to Infer "Ought" From "Is"? The Role of Biases in Explanation.

    PubMed

    Tworek, Christina M; Cimpian, Andrei

    2016-08-01

    People tend to judge what is typical as also good and appropriate-as what ought to be. What accounts for the prevalence of these judgments, given that their validity is at best uncertain? We hypothesized that the tendency to reason from "is" to "ought" is due in part to a systematic bias in people's (nonmoral) explanations, whereby regularities (e.g., giving roses on Valentine's Day) are explained predominantly via inherent or intrinsic facts (e.g., roses are beautiful). In turn, these inherence-biased explanations lead to value-laden downstream conclusions (e.g., it is good to give roses). Consistent with this proposal, results from five studies (N = 629 children and adults) suggested that, from an early age, the bias toward inherence in explanations fosters inferences that imbue observed reality with value. Given that explanations fundamentally determine how people understand the world, the bias toward inherence in these judgments is likely to exert substantial influence over sociomoral understanding. PMID:27485133

  2. Waves and Patterns in Chemical and Biological Media

    NASA Astrophysics Data System (ADS)

    Swinney, Harry L.; Krinsky, Valentin I.

    1991-12-01

    These 28 contributions by leading researchers - from such diverse disciplines as chemistry, biology, physics, mathematics, and physiology - describe recent experiments, numerical simulations, and theoretical analyses of the formation of spatial patterns in chemical and biological systems. Chemical patterns have been systematically studied since the field was established by Alan Turing's landmark 1952 paper, "The chemical basis for morphogenesis," yet only recently have new experimental techniques and numerical analyses of reaction-diffusion equations opened the way to understanding stationary and traveling wave patterns. This collection summarizes the exciting developments in this rapidly growing field. It shows that some biological patterns have been found to be strikingly similar to patterns found in simple, well-controlled laboratory chemical systems, that new chemical reactor designs make it possible to sustain chemical patterns and to study transitions between different kinds of patterns, and that nearly 40 years after Turing's paper, the patterns predicted by Turing have finally been observed in laboratory experiments. Harry L. Swinney is Sid Richardson Foundation Regents Chair, Department of Physics, and Director of the Center for Nonlinear Dynamics at the University of Texas at Austin. Valentin I. Krinsky is Head of the Autowave Laboratory, Institute of Biological Physics, Academy of Sciences, Pushchino, USSR. Chapters cover: Spiral, Ring, and Scroll Patterns: Experiments. Spiral, Ring, and Scroll Patterns: Theory and Simulations. Fronts and Turing Patterns. Waves and Patterns in Biological Systems.

  3. The Quantum Underground: Early quantum theory textbooks

    NASA Astrophysics Data System (ADS)

    Gearhart, Clayton

    2011-04-01

    Quantum theory had its beginnings in 1900, when Max Planck derived his famous formula for the energy density of black-body radiation. But the early quantum theory textbooks we remember today--for example, those of Arnold Summerfeld (1919), Fritz Reiche (1921), and a shorter Report by James Jeans (1914), did not appear until some years later, and all were written by physicists who were themselves active participants in early quantum theory. Surprisingly, not all early texts fit this pattern. Reiche himself had written a review article on quantum theory for general readers in Die Naturwissenschaften in 1913, long before his research had shifted to quantum topics. And a year later, textbooks by Hermann Sieveking and Sigfried Valentiner treated quantum theory for students and non-specialists, although neither was active in quantum theoretical research. A third and better known author, Owen Richardson, also treated quantum theory in a 1914 book on electromagnetism. I will describe these early and little-known treatments of quantum theory, all of which were written by physicists whose primary research and professional interests lay elsewhere.

  4. Selenium and glutathione peroxidase reference values in whole blood and plasma of a reference population living in Valencia, Spain.

    PubMed

    Alegría, A; Barberá, R; Clemente, G; Farré, R; García, M J; Lagarda, M J

    1996-12-01

    In order to assess the reference values for selenium nutritional status, adequate indicators (selenium concentration and glutathione peroxidase activity) were determined in whole blood and blood derivates of a healthy population (n = 287) from the province of Valencia, Spain. The reference population was selected by applying preestablished criteria. Selenium in whole blood and plasma was measured by graphite furnace atomic absorption spectrometry (GFAAS), with a deuterium correction, after addition of Pd/Mg(NO3)2 as the matrix modifier and appropriate dilution. Accuracy was checked by means of a reference material (Seronorm Trace Metals serum and whole blood). The population's reference intervals for selenium content at a 95% confidence level were: 53.03-108.96 and 66.71-119.4 mg/L for plasma and whole blood selenium concentration respectively. GPX activity was measured using a modification of the Paglia and Valentine method, and the reference intervals obtained ranged from 196 to 477 U/L in plasma, from 49 to 93 U/gHb in erythrocytes and from 52 to 96 U/gHb in whole blood. The only statistically significant differences detected between men and women are for to the GPX activity in whole blood. The results obtained are in the range of values found by others authors in healthy populations residing in different European countries. PMID:9021673

  5. Cross-modality priming for people's adjectivized names: failure to support the adjectivization hypothesis.

    PubMed

    Mukai, Akira

    2005-04-01

    This experiment tested a prediction derived from Hollis and Valentine's 2001 adjectivization hypothesis, that having an adjectival form is the key factor that makes certain classes of proper names, i.e., country names, exhibit a common name-like pattern of long-term priming. The hypothesis predicted that, when adjectivized historical celebrity names, e.g., William Shakespeare/Shakespearean, were compared with nonadjectivized historical celebrity names, e.g., Emile Zola, cross-modality long-term priming in a familiarity decision task would occur only for nonadjectivized name stimuli. 32 students of literature, history, or philosophy (21 women and 11 men; age range 18-41 years, M age = 22.4 yr.) were tested. Priming was measured by latency of response. Analysis showed that the mean RT to primed items was faster than the mean RT to unprimed items when the prime task was presented in both visual and auditory modalities both for the adjectivized and nonadjectivized names. Contrary to the hypothesis, cross-modality priming was observed regardless of the adjectivization of name stimuli. The findings of the present experiment did not support the adjectivization hypothesis. PMID:15941119

  6. Usefulness of double locus sequence typing (DLST) for regional and international epidemiological surveillance of methicilin-resistant Staphylococcus aureus.

    PubMed

    Basset, P; Senn, L; Prod'hom, G; Bille, J; Francioli, P; Zanetti, G; Blanc, D S

    2010-08-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of nosocomial infections worldwide. To differentiate reliably among S. aureus isolates, we recently developed double locus sequence typing (DLST) based on the analysis of partial sequences of clfB and spa genes. In the present study, we evaluated the usefulness of DLST for epidemiological investigations of MRSA by routinely typing 1242 strains isolated in Western Switzerland. Additionally, particular local and international collections were typed by pulsed field gel electrophoresis (PFGE) and DLST to check the compatibility of DLST with the results obtained by PFGE, and for international comparisons. Using DLST, we identified the major MRSA clones of Western Switzerland, and demonstrated the close relationship between local and international clones. The congruence of 88% between the major PFGE and DLST clones indicated that our results obtained by DLST were compatible with earlier results obtained by PFGE. DLST could thus easily be incorporated in a routine surveillance procedure. In addition, the unambiguous definition of DLST types makes this method more suitable than PFGE for long-term epidemiological surveillance. Finally, the comparison of the results obtained by DLST, multilocus sequence typing, PFGE, Staphylococcal cassette chromosome mec typing and the detection of Panton-Valentine leukocidin genes indicated that no typing scheme should be used on its own. It is only the combination of data from different methods that gives the best chance of describing precisely the epidemiology and phylogeny of MRSA. PMID:19832717

  7. Nasopharyngeal carriage of Staphylococcus aureus among imprisoned males from Brazil without exposure to healthcare: risk factors and molecular characterization

    PubMed Central

    2014-01-01

    Background Previous studies report high prevalence of Methicillin-resistant Staphylococcus aureus (MRSA) colonization among imprisoned populations. However, there are no data on that prevalence in Brazilian correctional institutions. Findings We tested 302 male prisoners for nasopharyngeal colonization with Staphylococcus aureus from February 2009 through April 2010. The overall isolation rate of S. aureus was 16.5% (50/302). Men who had sex with men, users of inhalatory drugs and those with previous lung or skin diseases were more likely to be colonized with S. aureus. MRSA was isolated from 0.7% of subjects (2/302). The two Community-associated (CA)-MRSA belonged to ST5 but were unrelated based on the PFGE results. Both harbored SCCmec IV, and did not possess the Panton-Valentine Leukocidin gene. Conclusion We found low prevalence of S. aureus and CA-MRSA among prisoners. MRSA isolates ST5 from two subjects harboured SCCmec IV and presented different PFGE patterns. PMID:24990470

  8. [About the origin, evolution and irradiation of Mexican cardiology].

    PubMed

    de Micheli, Alfredo

    2014-01-01

    The Mexican cardioangiology started in the nineteen century thanks to first endeavors of surgeons and physicians related to local academies and to School of Medicine, established in 1833 by Dr. Valentin Gómez Farías. Dr. Manuel Carpio, the future first head of department of physiology in this school, translated to Spanish language and published, in 1823, the article On pectoriloquo of the French physician Marat and later performed some experiments on the heart' motion. During the Secont Empire (1864-1867), the physician Samuel von Basch performed studies to define the arterial hypertension, called by him "latent atherosclerosis", i.e. the "essential hypertension". Once he had returned to his country, he invented in 1880, a sphygmomanometer of mercury column, that was the model for the instrument constructed by the Italian physician Scipione Riva-Rocci and presented in 1896. In our time, Dr. Demetrio Sodi Pallares systematized a metabolic therapy called "polarizing therapy", i.e. capable of repolarizing the heart's cells partly depolarized due to hypoxia or direct aggressions. These were the first steps in Mexico on the way to a promising medicine starting and the great adventure of Mexican cardiology. PMID:25260577

  9. Development of a novel multiplex electrochemiluminescent-based immunoassay for quantification of human serum IgG against 10 Staphylococcus aureus toxins.

    PubMed

    Adhikari, Rajan P; Haudenschild, Christian; Sterba, Patricia M; Sahandi, Sara; Enterlein, Sven; Holtsberg, Frederick W; Aman, M Javad

    2016-03-01

    An electrochemiluminescent (ECL)-based multiplex immunoassay using Meso-Scale Discovery (MSD) technology was developed for detecting antibody response toward 10 Staphylococcus aureus (S. aureus) exotoxins. These 10 antigens included three different groups of toxins: 1) single component pore-forming toxins such as alpha- and delta-hemolysins, 2) the bicomponent pore-forming toxin Panton-Valentine leukocidin (PVL), comprised of LukS-PV and LukF-PV subunits, and 3) enterotoxin/superantigens - Staphylococcal enterotoxins A (SEA), B (SEB), C1 (SEC1), D (SED), K (SEK) and Toxic shock syndrome toxin-1 (TSST-1). Assay development included optimization steps with a conventional SEB ELISA-based serological assay and then optimized parameters were transferred and re-optimized in a singleplex ECL format. Finally, two pentaplex solid-phase ECL formats were developed. As proof of concept, one set of pentaplex ECL data was compared with conventional ELISA results. During the assay development controls were screened and developed for both the singleplex and multiplex assays. ECL-based multiplex assays were more sensitive with a wide dynamic range and proved more time-efficient than conventional ELISAs. Using the newly developed ECL method we showed, for the first time, that delta-hemolysin toxin can induce an immune response as antibody titers could be detected. PMID:26826278

  10. Human Monocyte-Derived Osteoclasts Are Targeted by Staphylococcal Pore-Forming Toxins and Superantigens.

    PubMed

    Flammier, Sacha; Rasigade, Jean-Philippe; Badiou, Cédric; Henry, Thomas; Vandenesch, François; Laurent, Frédéric; Trouillet-Assant, Sophie

    2016-01-01

    Staphylococcus aureus is the leading cause of bone and joint infections (BJIs). Staphylococcal pathogenesis involves numerous virulence factors including secreted toxins such as pore-forming toxins (PFTs) and superantigens. The role of these toxins on BJI outcome is largely unknown. In particular, few studies have examined how osteoclasts, the bone-resorbing cells, respond to exposure to staphylococcal PFTs and superantigens. We investigated the direct impact of recombinant staphylococcal toxins on human primary mature monocyte-derived osteoclasts, in terms of cytotoxicity and cell activation with cell death and bone resorption assays, using macrophages of the corresponding donors as a reference. Monocyte-derived osteoclasts displayed similar toxin susceptibility profiles compared to macrophages. Specifically, we demonstrated that the Panton-Valentine leukocidin, known as one of the most powerful PFT which lyses myeloid cells after binding to the C5a receptor, was able to induce the death of osteoclasts. The archetypal superantigen TSST-1 was not cytotoxic but enhanced the bone resorption activity of osteoclasts, suggesting a novel mechanism by which superantigen-producing S. aureus can accelerate the destruction of bone tissue during BJI. Altogether, our data indicate that the diverse clinical presentations of BJIs could be related, at least partly, to the toxin profiles of S. aureus isolates involved in these severe infections. PMID:26934588

  11. Staphylococcus aureus nasal carriage among healthcare workers in Kisangani, the Democratic Republic of the Congo.

    PubMed

    De Boeck, H; Vandendriessche, S; Hallin, M; Batoko, B; Alworonga, J-P; Mapendo, B; Van Geet, C; Dauly, N; Denis, O; Jacobs, J

    2015-08-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a global health concern, but there are few data from Central Africa. The objective of our study was to characterise S. aureus colonisation isolates from healthcare-exposed professionals in the Democratic Republic of the Congo (DRC). Healthcare workers and medical students (n = 380) in Kisangani, DRC were screened for S. aureus nasal carriage in a single-centre cross-sectional study in the University Hospital of Kisangani. The isolates were identified and characterised using phenotypic and genotypic methods. The nasal carriage rate of S. aureus was 16.6 % and 10 out of 63 isolates (15.9 %) were MRSA. We found 28 different spa types. Most MRSA isolates belonged to ST8-spa t1476-SCCmec V. The majority of MRSA were multidrug-resistant to non-beta-lactam antibiotics. Overall, 28.5 % of S. aureus carried Panton-Valentine leucocidin (PVL)-encoding genes (all methicillin-sensitive) and 17.5 % carried toxic shock syndrome toxin-1 (TSST-1)-encoding genes. The finding of MRSA carriage among healthcare workers in a setting with limited access to diagnostic microbiology and appropriate therapy calls for improved education on infection control practices and supports the introduction of surveillance programmes. PMID:25931131

  12. Molecular characterization of methicillin-resistant Staphylococcus aureus strains from pet animals and veterinary staff in China.

    PubMed

    Zhang, Wanjiang; Hao, Zhihui; Wang, Yang; Cao, Xingyuan; Logue, Catherine M; Wang, Bing; Yang, Jing; Shen, Jianzhong; Wu, Congming

    2011-11-01

    The aim of this study was to determine the epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) isolates from pet animals and veterinary staff and the characteristics of these isolates. A total of 22 MRSA isolates were isolated from nasal swabs from dogs, cats and veterinary staff in six pet hospitals in six cities, and examined for antimicrobial susceptibility, the presence of resistance genes, Panton-Valentine leukocidin gene lukF-lukS, staphylococcal chromosomal cassette (SCC) mec typing, spa tying, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. Of 22 MRSA isolates, 21 were recovered from pet animals, and one was isolated from a member of sstaff. All 22 MRSA strains were resistant to penicillin, oxacillin, azithromycin, clindamycin and ceftriaxone, and harboured mecA, ermB and linA genes. The lukF-lukS gene was not detected in any of the MRSA isolates. Eighteen MRSA strains from Qingdao belonged to ST59-MRSA-IV-spa t437. Of four MRSA isolates from Beijing, one belonged to ST398-MRSA-V-spa t034, and three belonged to ST239-MRSA-III-spa t030 profiles. Two PFGE types (A and B) were identified. Two isolates originating from dogs and one isolate originating from a staff member in Beijing shared similar PFGE patterns. Our cumulative data suggested that cross-transmission of MRSA may have occurred between pet animals and veterinary staff. PMID:21382731

  13. Characteristics of the community-genotype sequence type 72 methicillin-resistant Staphylococcus aureus isolates that underlie their persistence in hospitals.

    PubMed

    Joo, Eun-Jeong; Choi, Ji-Young; Chung, Doo Ryeon; Song, Jae-Hoon; Ko, Kwan Soo

    2016-06-01

    Panton-Valentine leukocidin-negative methicillin-resistant Staphylococcus aureus (MRSA) clone ST72, known as a major community-associated MRSA in Korea, has emerged as an important pathogen in hospitals. To understand bacterial properties that underlie transformation of this clone into a nosocomial pathogen, we compared characteristics of the community-genotype ST72 MRSA isolates with those of ST5 and ST239 MRSA, which have been predominant nosocomial MRSA clones in Korea. Several genes associated with adhesion and virulence were absent or rarely found in ST72 isolates. Many ST72 isolates (70.1%) belonged to agr group I, but the agr group of other ST72 isolates could not be determined. As indicated by d-hemolysin production, ST72 isolates expressed fully functional agr, whereas agr dysfunction was observed in ST5 and ST239 isolates. In the biofilm formation assay, no upregulation of biofilm-forming activity of ST72 MRSA was detected. However, ST72 isolates demonstrated persistence under hypotonic and desiccating conditions (survival rates 72.3% and 33.9%, respectively), which was similar to characteristics of ST5 or ST239 isolates. ST72- MRSA isolates showed low virulence, but properties of their functional agr system could facilitate their spread in hospitals. In conclusion, tolerance to stressful environments, e.g., hypotonic and dry conditions, may also contribute to survival of the community-associated MRSA clones in healthcare facilities. PMID:27225462

  14. Surface energy of zinc. [Effective cleavage surface energy

    SciTech Connect

    Bilello, J.C.; Dew-Hughes, D.; Pucino, A.T.

    1981-01-01

    The influence of temperature and associated dislocation microstructure on the energetics of basal plane cleavage in zinc crystals has been investigated using the method of Hull, Beardmore and Valentine (HBV). A marked temperature dependence was observed in the zinc surface energy, over the range 77 to 298/sup 0/K, contrary to previous expectations. Plastic relaxation was associated with crack initiation at 77/sup 0/K, but not propagation, while at room temperature a plastic zone of 1200-1500 ..mu..m in depth was produced by crack extension. The surface energy could be estimated, independent of the usual Griffith analysis, by measuring the energy dissipation in a fully relaxed deformed zone associated with an explosively formed precursor crack. This method yielded surface energies of 0.066 to 0.079 J-m/sup -2/ which was in good agreement with previous work. It is demonstrated that the cleavage surface energy of zinc is well below the thermodynamic surface energy and that this discrepancy is not related to plastic deformation. 7 figures, 1 table.

  15. Surface energy of zinc

    SciTech Connect

    Bilello, J.C.; Dew-Hughes, D.; Pucino, A.T.

    1983-04-01

    The influence of temperature and associated dislocation microstructure on the energetics of basal plane cleavage in zinc crystals has been investigated using the method of Hull, Beardmore, and Valentine (HBV). A marked temperature dependence was observed in the zinc surface energy, over the range 77--298 /sup 0/K, contrary to previous expectations. Plastic relaxation was associated with crack initiation at 77 /sup 0/K, but not propagation; while at room temperature a plastic zone of 1200--1500 ..mu..m in depth was produced by crack extension. The surface energy could be estimated, independent of the usual Griffith analysis, by measuring the energy dissipation in a fully relaxed deformed zone associated with an explosively formed precursor crack. This method yielded surface energies of 0.066 to 0.079 J m/sup -2/ which was in good agreement with previous work. It is demonstrated that the cleavage surface energy of zinc is well below the thermodynamic surface energy and that this discrepancy is not related to plastic deformation.

  16. Variability of antibiotic susceptibility and toxin production of Staphylococcus aureus strains isolated from skin, soft tissue, and bone related infections

    PubMed Central

    2013-01-01

    Background Staphylococcus aureus is an opportunistic commensal bacterium that mostly colonizes the skin and soft tissues. The pathogenicity of S. aureus is due to both its ability to resist antibiotics, and the production of toxins. Here, we characterize a group of genes responsible for toxin production and antibiotic resistance of S. aureus strains isolated from skin, soft tissue, and bone related infections. Results A total of 136 S. aureus strains were collected from five different types of infection: furuncles, pyomyositis, abscesses, Buruli ulcers, and osteomyelitis, from hospital admissions and out-patients in Benin. All strains were resistant to benzyl penicillin, while 25% were resistant to methicillin, and all showed sensitivity to vancomycin. Panton-Valentine leukocidin (PVL) was the most commonly produced virulence factor (70%), followed by staphylococcal enterotoxin B (44%). Exfoliative toxin B was produced by 1.3% of the strains, and was only found in isolates from Buruli ulcers. The tsst-1, sec, and seh genes were rarely detected (≤1%). Conclusions This study provides new insight into the prevalence of toxin and antibiotic resistance genes in S. aureus strains responsible for skin, soft tissue, and bone infections. Our results showed that PVL was strongly associated with pyomyositis and osteomyelitis, and that there is a high prevalence of PVL-MRSA skin infections in Benin. PMID:23924370

  17. Sulfur Dioxide Inhibition of Translocation in Bean Plants 1

    PubMed Central

    Teh, Kwang Ho; Swanson, Carroll A.

    1982-01-01

    Exposure of the source leaf of bean (Phaseolus vulgaris L. cv. Black Valentine) for 2 hours to 2.9 microliters per liter SO2 inhibited the net photosynthetic rate an average of 75% and, simultaneously, the translocation rate an average of 45%. Calculations indicated that the experimentally determined translocation rates from SO2-stressed leaves were lower than were the rates expected on the basis of the observed reductions in photosynthesis. It is inferred that, under SO2 stress, the phloem-loading system becomes a major limiting step in controlling the translocation rate. Following removal of SO2, photosynthesis recovered quite rapidly (to about 60% of its preexposure rate within 2 hours), but the translocation rate failed to increase during this time interval. This delayed response of translocation to removal of SO2 does not appear to be due to an injury effect of SO2, inasmuch as a similar effect was obtained by exposing the source leaf to a short (2-hour) interval of dark. PMID:16662191

  18. Metro system in Guangzhou as a hazardous reservoir of methicillin-resistant Staphylococci: findings from a point-prevalence molecular epidemiologic study

    PubMed Central

    Peng, Yang; Ou, Qianting; Lin, Dongxin; Xu, Ping; Li, Ying; Ye, Xiaohua; Zhou, Junli; Yao, Zhenjiang

    2015-01-01

    Staphylococci are common causes of healthcare-associated and community-associated infections. However, limited data are available on the prevalence, phenotypes and molecular characteristics of Staphylococci in metro system around the world. 320 surface samples were collected from the Guangzhou metro system to isolate and characterize Staphylococci strains. Of the samples, 75.6% (242/320) were contaminated with Staphylococci. The Staphylococci isolates, especially the methicillin resistant isolates, were resistance to most of the antibiotics, with 79.8% (193/242) classified as multidrug resistant (MDR) strains. 8 strains of methicillin-resistant Staphylococcus aureus (MRSA) carried a range of staphylococcal cassette chromosome mec (SCCmec) types [I (1), II (3), III (2) and NT (2)]. Staphylococcus aureus isolates were classified into several ST types and showed possible cross transmissions of strains from various sources. All MRSA strains were positive for the qac gene, and only one methicillin-susceptible Staphylococci aureus (MSSA) strain was positive for the Panton-Valentine leukocidin (PVL) genes. This study demonstrated that environmental surfaces in the Guangzhou metro system may be a hazardous reservoir for transmission of Staphylococci to passengers. The resistance to antibiotics and disinfectants observed among isolates was also noteworthy. PMID:26513750

  19. Methicillin resistance in Staphylococcus aureus strains isolated from food and wild animal carcasses in Italy.

    PubMed

    Traversa, A; Gariano, G R; Gallina, S; Bianchi, D M; Orusa, R; Domenis, L; Cavallerio, P; Fossati, L; Serra, R; Decastelli, L

    2015-12-01

    Following the detection of methicillin-resistant Staphylococcus aureus (MRSA) ST398 in food-producing animals, both livestock and wildlife, and derived products, are considered potential sources of MRSA in humans. There is a paucity of data on MRSA in foods in Italy, and the data regarding wild animals are particularly scarce. A total of 2162 food samples collected during official monitoring activities in 2008 were analyzed for the detection of S. aureus. Also, samples from 1365 wild animals collected by the National Reference Center for Wild Animal Diseases in 2003-2009 were subjected to anatomopathological examination. S. aureus isolates were processed for phenotypic and molecular methicillin resistance determinations. S. aureus was found in 2.0% of wild animal carcasses and in 3.2% of wild boar lymph nodes: none showed methicillin resistance. The prevalence of S. aureus in food was 17.1%. Two MRSA strains, both from bulk tank milk (prevalence 0.77%) were isolated: the strains were resistant to tetracycline, had spa-type t899, and were negative for the Panton-Valentine leukocidin gene. The low prevalence of MRSA suggests that the risk of transmission to humans via food is limited. However, attention should be paid to the cattle food chain, which may be a potential route of transmission of LA-MRSA. PMID:26338130

  20. LukS-PV induces differentiation by activating the ERK signaling pathway and c-JUN/c-FOS in human acute myeloid leukemia cells.

    PubMed

    Dai, Chunyang; Zhang, Chengfang; Sun, Xiaoxi; Pan, Qing; Peng, Jing; Shen, Jilong; Ma, Xiaoling

    2016-07-01

    LukS-PV, a component of Panton-Valentine leukocidin, is a pore-forming cytotoxin secreted by Staphylococcus aureus. Here we examined the potential effect of LukS-PV in differentiation of human leukemia cells and the underlying mechanism. We found that LukS-PV could induce differentiation of human acute myeloid leukemia (AML) cells, including AML cell lines and primary AML blasts, as determined by morphological changes, phagocytosis assay and expression of CD14 and CD11b surface antigens. In addition, LukS-PV activated the extracellular signal-regulated kinase (ERK) pathway and significantly upregulated the phosphorylation of c-JUN and c-FOS transcriptional factors in the process of differentiation. Inhibiting ERK pathway activation with U0126 (a MEK1/2 inhibitor) markedly blocked LukS-PV-induced differentiation and decreased the phosphorylation of c-JUN and c-FOS. These findings demonstrate an essential role for the ERK pathway together with c-JUN and c-FOS in the differentiation activity of LukS-PV. Taken together, our data suggest that LukS-PV could be a potential candidate as a differentiation-inducing agent for the therapeutic treatment of AML. PMID:27102414

  1. Now We Know: Assessing Sexual Assault Criminal Justice Case Processing in an Urban Community Using the Sexual Assault Nurse Practitioner Evaluation Toolkit.

    PubMed

    Valentine, Julie L; Shaw, Jessica; Lark, Alyssa; Campbell, Rebecca

    2016-01-01

    Campbell and colleagues developed an evaluation Toolkit for use by sexual assault nurse examiners (SANEs) to assess criminal case outcomes in adult sexual assault cases seen by SANE programs (Campbell, Townsend, Shaw, Karim, & Markowitz, 2014; Campbell, Bybee, et al., 2014). The Toolkit provides step-by-step directions and an easy-to-use statistical program. This study describes implementation of the Toolkit in Salt Lake County, the first site outside the pilot sites to utilize the program. The Toolkit revealed that, in Salt Lake County from 2003 to 2011, only 6% of adult sexual assault cases were successfully prosecuted. These findings prompted multiple community discussions, media attention, and a call to action to improve the investigation and prosecution of adult sexual assault cases. The primary purpose of this case report is to encourage other SANE teams and communities to use the Toolkit by sharing the successful experience of Salt Lake County in implementing the Toolkit.Video Abstract available for additional insights from Dr. Valentine (see Supplemental Digital Content 1, http://links.lww.com/JFN/A19). PMID:27496646

  2. Molecular features of heterogeneous vancomycin-intermediate Staphylococcus aureus strains isolated from bacteremic patients

    PubMed Central

    2009-01-01

    Background Heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) bacteremia is an emerging infection. Our objective was to determine the molecular features of hVISA strains isolated from bacteremic patients and to compare them to methicillin resistant S. aureus (MRSA) and methicillin sensitive S. aureus (MSSA) blood isolates. Results We assessed phenotypic and genomic changes of hVISA (n = 24), MRSA (n = 16) and MSSA (n = 17) isolates by PCR to determine staphylococcal chromosomal cassette (SCCmec) types, Panton-Valentine leukocidin (PVL) and the accessory gene regulator (agr) loci. Biofilm formation was quantified. Genetic relatedness was assessed by PFGE. PFGE analysis of isolates was diverse suggesting multiple sources of infection. 50% of hVISA isolates carried SCCmec type I, 21% type II; 25% type V; in 4% the SCCmec type could not be identified. Among MRSA isolates, 44% were SCCmec type I, 12.5% type II, 25% type V, 12.5% were non-typable, and 6% were SCCmec type IVd. Only one hVISA isolate and two MSSA isolates carried the PVL. Biofilm formation and agr patterns were diverse. Conclusion hVISA isolates were diverse in all parameters tested. A considerable number of hVISA and MRSA strains carried the SCCmec type V cassette, which was not related to community acquisition. PMID:19732456

  3. Clonal expansion accounts for an excess of antimicrobial resistance in Staphylococcus aureus colonising HIV-positive individuals in Lagos, Nigeria.

    PubMed

    Olalekan, Adesola O; Schaumburg, Frieder; Nurjadi, Dennis; Dike, Adobi E; Ojurongbe, Olusola; Kolawole, Deboye O; Kun, Jürgen F; Zanger, Philipp

    2012-09-01

    Nasal colonisation with Staphylococcus aureus is a risk factor for invasive infection in human immunodeficiency virus (HIV)-positive individuals. This study aimed to characterise colonising S. aureus from regions with a high HIV prevalence. Single nasal swabs were taken from a total of 374 HIV-positive and 370 healthy individuals. Overall, 202 S. aureus carriers were detected. Compared with healthy individuals, HIV-positive subjects were more likely to be S. aureus nasal carriers (33% vs. 21%; P=0.0001). Isolates from HIV-positive individuals were more often resistant to meticillin (16% vs. 8%; P=0.13), chloramphenicol (47% vs. 16%; P<0.0001), sulfamethoxazole/trimethoprim (SXT) (90% vs. 55%; P<0.0001) and ciprofloxacin (18% vs. 0%; P<0.0001). Strains belonging to the spa clonal complexes 3772/ST25 and 064/ST8 were significantly more often isolated from HIV-positive individuals and exhibited greater resistance to ciprofloxacin, SXT and chloramphenicol (spa-CC 3772) or to meticillin (spa-CC 064), respectively. Panton-Valentine leukocidin gene content was high overall and was equally distributed between isolates from HIV-positive and healthy individuals (33% vs. 30%). Genotypic characteristics of colonising isolates were similar to those reported to cause invasive infection in Nigeria. The HIV pandemic contributes to the evolution of antimicrobial resistance in S. aureus. Measures to contain antimicrobial resistance of S. aureus in Nigeria must target risk groups such as HIV-positive individuals. PMID:22831840

  4. Methicillin-resistant Staphylococcus aureus in central Iowa wildlife.

    PubMed

    Wardyn, Shylo E; Kauffman, Lin K; Smith, Tara C

    2012-10-01

    Livestock and pets have been identified as carriers of Staphylococcus aureus; however, the role of wild animals as a reservoir of S. aureus strains has not yet been examined. We conducted a pilot study to determine the prevalence of methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) in 37 species of wild animals rehabilitated at a university clinic. Nasal, wing, wound, and cloacal swabs were collected. Of 114 animals, seven (6.1%) were MSSA-positive and three (2.6%) were MRSA-positive. The MRSA isolates were obtained from two eastern cottontail rabbits (Sylvilagus floridanus) and a Lesser Yellowlegs (Tringa flavipes), a migratory shorebird. Antibiotic resistance testing of the MRSA isolates revealed that two were additionally resistant to tetracycline and erythromycin, and the third isolate was also resistant to erythromycin, clindamycin, and levofloxacin. All three isolates were positive for the Panton-Valentine leukocidin (PVL) gene. Sequence typing of the staphylococcal protein A (spa) region revealed one MRSA isolate to be t002, whereas the other two MRSA isolates were found to be t008. Our results suggest that S. aureus, including MRSA, is being carried by wild animals, although at a low prevalence with the limited number of animals tested. Additional studies are needed to determine how this may impact human health. PMID:23060511

  5. Relative faces: encoding of family resemblance relative to gender means in face space.

    PubMed

    Griffin, Harry John; McOwan, Peter William; Johnston, Alan

    2011-01-01

    Neurophysiological (W. A. Freiwald, D. Y. Tsao, & M. S. Livingstone, 2009; D. A. Leopold, I. V. Bondar, & M. A. Giese, 2006) and psychophysical (D. A. Leopold, A. J. O'Toole, T. Vetter, & V. Blanz, 2001; G. Rhodes & L. Jeffery, 2006; R. Robbins, E. McKone, & M. Edwards, 2007) evidence suggests that faces are encoded as differences from a mean or prototypical face, consistent with the conceptual framework of a mean-centered face space (T. Valentine, 1991). However, it remains unclear how we encode facial similarity across classes such as gender, age, or race. We synthesized Caucasian male and female cross-gender "siblings" and "anti-siblings" by projecting vectors representing deviations of faces from one gender mean into another gender. Subjects perceived male and female pairings with similar vector deviations from their gender means as more similar, and those with opposite vector deviations as less similar, than randomly selected cross-gender pairings. Agreement in relative direction in a space describing how facial images differ from a mean can therefore provide a basis for perceived facial similarity. We further demonstrate that relative coding for male and female faces is based on the activation of a shared neural population by the transfer of an identity aftereffect between a face and its cross-gender sibling. These results imply whereas structural similarity may be reflected in the Euclidean distance between points in face space configural similarity may be coded by direction in face space. PMID:22003253

  6. Current concepts on the virulence mechanisms of meticillin-resistant Staphylococcus aureus.

    PubMed

    Watkins, Richard R; David, Michael Z; Salata, Robert A

    2012-09-01

    Meticillin-resistant Staphylococcus aureus (MRSA) strains are prevalent bacterial pathogens that cause both health care and community-associated infections. Increasing resistance to commonly prescribed antibiotics has made MRSA a serious threat to public health throughout the world. The USA300 strain of MRSA has been responsible for an epidemic of community-associated infections in the US, mostly involving skin and soft tissue but also more serious invasive syndromes such as pneumonia, severe sepsis and endocarditis. MRSA strains are particularly serious and potentially lethal pathogens that possess virulence mechanisms including toxins, adhesins, enzymes and immunomodulators. One of these is Panton-Valentine leukocidin (PVL), a toxin associated with abscess formation and severe necrotizing pneumonia. Earlier studies suggested that PVL was a major virulence factor in community-associated MRSA infections. However, some recent data have not supported this association while others have, leading to controversy. Therefore, investigators continue to search for additional mechanisms of pathogenesis. In this review, we summarize the current understanding of the biological basis of MRSA virulence and explore future directions for research, including potential vaccines and antivirulence therapies under development that might allow clinicians to more successfully treat and prevent MRSA infections. PMID:22745137

  7. Going beyond DFT for Organic/Titanium Dioxide interfaces

    NASA Astrophysics Data System (ADS)

    Jorge, Leonardo M. Marion; Alves-Santos, Marcelo; Caldas, Marília J.

    2012-02-01

    There is increasing interest in organic/oxide interfaces, particularly for light harvesting and light-emitting devices, and it is important to obtain theoretical information for basic quantities such as the energy-level alignment across the interface. Accurate descriptions of the electronic structure of the composite system, as e.g. [1], are however scarce. The method used should give reliable results for both organic and oxide materials, to guarantee a good description of the hybrid system. In this work we have explored different DFT functionals (PZ-LDA, and those that include a fraction of Exact-Exchange as PBE0, HSE and B3LYP [2]) and compared the results with those obtained by Many-Body Perturbation theory with the GW approximation[3]. We have chosen as prototype systems TiO2, both bulk crystal and model surface, and Thiophene. We have found that none of the used DFT schemes give optimal results for both organic and inorganic systems at the same time, so moving beyond DFT is mandatory.[4pt] [1] C.D. Valentin et.al., Phys. Rev. Lett. 97, 166803 (2006)[0pt] [2] J.P. Perdew et.al., J. Chem. Phys. 105, 9982 (1996); J. Heyd et.al., J. Chem. Phys. 118, 8207 (2003); P.J. Stephens et.al., J. Phys. Chem. 98, 11623 (1994)[0pt] [3] A. Marini et.al., Comp. Phys. Comm. 180, 1392 (2009)

  8. Prevalence, antimicrobial resistance, and molecular characterization of methicillin-resistant Staphylococcus aureus from bulk tank milk of dairy herds.

    PubMed

    Kreausukon, K; Fetsch, A; Kraushaar, B; Alt, K; Müller, K; Krömker, V; Zessin, K-H; Käsbohrer, A; Tenhagen, B-A

    2012-08-01

    It was the objective of the study to estimate the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in bulk tank milk from German dairy herds and to characterize isolates from bulk tank milk with respect to their Staph. aureus protein A (spa) and staphylococcal cassette chromosome mec (SCCmec) type, their phenotypic antimicrobial resistance and resistance- resp. virulence-associated genes using broth microdilution and a microarray for Staph. aureus. Bulk tank milk samples (25 mL) were tested for MRSA using a 2-step selective enrichment protocol. Presumptive MRSA were confirmed by PCR. Thirty-six isolates collected from bulk tank milk of dairy herds in 2009 and 2010 were included in the characterization. All isolates displayed spa-types assigned to the clonal complex CC398. Based on the epidemiological cut-off values for the interpretation of minimum inhibitory concentrations isolates were resistant to tetracycline (100%), clindamycin (58%), erythromycin (52%), quinupristin/dalfopristin (36%), and kanamycin (27%). Isolates did not carry genes associated with typical virulence factors for Staph. aureus such as the Panton-Valentine leukocidin. However, they did carry hemolysin genes. Livestock-associated MRSA of CC398 does occur in German dairy herds and the strains have similar properties as described for strains from pigs. PMID:22818451

  9. Community-Associated Methicillin-Resistant Staphylococcus aureus Lacking PVL, as a Cause of Severe Invasive Infection Treated with Linezolid

    PubMed Central

    Gavino, Alexandra; Miragaia, Maria; Varandas, Luis; de Lencastre, Herminia; Brito, Maria Joao

    2013-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is an emerging public health problem worldwide. Severe invasive infections have been described, mostly associated with the presence of Panton-Valentine leukocidin (PVL). In Portugal limited information exists regarding CA-MRSA infections. In this study we describe the case of a previously healthy 12-year-old female, sport athlete, who presented to the hospital with acetabulofemoral septic arthritis, myositis, fasciitis, acetabulum osteomyelitis, and pneumonia. The MRSA isolated from blood and synovial fluid was PVL negative and staphylococcal enterotoxin type P (SEP) and type L (SEL) positive, with a vancomycin MIC of 1.0 mg/L and resistant to clindamycin and ciprofloxacin. The patient was submitted to multiple surgical drainages and started on vancomycin, rifampicin, and gentamycin. Due to persistence of fever and no microbiological clearance, linezolid was started with improvement. This is one of the few reported cases of severe invasive infection caused by CA-MRSA in Portugal, which was successfully treated with linezolid. In spite of the severity of infection, the MRSA isolate did not produce PVL. PMID:23509655

  10. Key genetic elements and regulation systems in methicillin-resistant Staphylococcus aureus.

    PubMed

    Hao, Haihong; Dai, Menghong; Wang, Yulian; Huang, Lingli; Yuan, Zonghui

    2012-11-01

    Methicillin-resistant Staphylococcus aureus (MRSA), popularly known as a type of superbug, has been a serious challenge for animal and human health. S. aureus has developed methicillin resistance mainly by expression of β-lactamase and PBP2a, which is regulated by the blaZ-blaI-blaR1 and mecA-mecI-mecRI systems. Other genetic elements, including murE and femA, also participate in expression of methicillin resistance, but the mechanism remains unclear. The evolution of the staphylococcal cassette chromosome mec determines the epidemiological risk of MRSA. The plasmid-located gene cfr might contribute to multiresistance and transmission of MRSA. Some virulence factors, including Panton-Valentine leukocidin, phenol-soluble modulin, arginine catabolic mobile element and other toxin elements enhance the pathogenesis and fitness of MRSA. Two-component regulation systems (agr, saeRS and vraRS) are closely associated with pathogenesis and drug resistance of MRSA. The systematic exploration of key genetic elements and regulation systems involved in multidrug resistance/pathogenesis/transmission of MRSA is conclusively integrated into this review, providing fundamental information for the development of new antimicrobial agents and the establishment of reasonable antibiotic stewardship to reduce the risk of this superbug. PMID:23075449

  11. Dissemination of methicillin-resistant Staphylococcus aureus SCCmec type IV and SCCmec type V epidemic clones in a tertiary hospital: challenge to infection control.

    PubMed

    Dhawan, B; Rao, C; Udo, E E; Gadepalli, R; Vishnubhatla, S; Kapil, A

    2015-01-01

    Two-hundred MRSA strains from inpatients with healthcare-associated (HA) and 100 MRSA strains from outpatients with community-associated (CA) skin and soft tissue infections (SSTIs) were tested for antimicrobial susceptibility, staphylococcal cassette chromosome mec (SCCmec) typing, Panton-Valentine leucocidin (PVL) toxin, seh and arcA genes. Based on SCCmec typing, HA-MRSA isolates were further divided into HA-SCCmec I/II/III MRSA and HA-SCCmec IV/V MRSA, and CA-MRSA isolates into CA-SCCmec I/II/III MRSA and CA-SCCmec IV/V MRSA. SCCmec types were further characterized by pulsed-field gel electrophoresis, spa typing and multi-locus sequence typing. Seventy-five (37·5%) HA-MRSA isolates and 83/100 CA-MRSA isolates were SCCmec IV/V genotype. HA-SCCmec IV/V MRSA was associated with malignancy (P = 0·03) and bone fractures (P = 0·02) compared to CA-SCCmec IV/V MRSA. HA-SCCmec IV/V MRSA was associated with PVL gene carriage compared to HA-SCCmec I/II/III MRSA (P < 0·001). ST22-MRSA-IV (EMRSA-15), ST772-MRSA-V, and ST36-MRSA-IV and ST239:EMRSA-I:III were the major clones identified. Our study documents the emergence of SCCmec IV and SCCmec V MRSA clones in an Indian hospital. PMID:24690229

  12. The historical seismicity and prediction of ground motion in northeast Mexico

    NASA Astrophysics Data System (ADS)

    Galván-Ramírez, Iván N.; Montalvo-Arrieta, Juan C.

    2008-02-01

    This work constitutes the first attempt to understand the seismic hazard in northeast Mexico. We present a compilation of regional seismicity in northeast Mexico (24-31°N, 97-106°W), finding 148 earthquakes for the 1787-2006 period. The study area lies within three morphotectonic provinces: Basin, Range, and Rio Grande rift; Sierra Madre Oriental; and Gulf coastal plain. Peak ground acceleration (PGA) maps were computed for three different scenarios: 1928 Parral, Chihuahua ( MW = 6.5); 1931 Valentine, Texas ( MW = 6.4); and a hypothetical earthquake located in central Coahuila. Ground motion values were computed using attenuation relations developed for central and eastern North America and the Basin and Range provinces. The earthquake in central Coahuila is considered a critical scenario for the main cities of northeast Mexico. The damage associated with this hypothetical earthquake could be severe because most buildings were constructed without seismic criteria. The expected PGA values in Monterrey, Saltillo, and Monclova are between 30 and 70 cm/s 2. This earthquake might also produce or trigger significant landslides and rock falls in the Sierra Madre Oriental, where several cities are located on the mountain range.

  13. [Revealing the structure of the nervous tissue III: From Jan Evangelista Purkyne (1787-1869) to Ludwig Mauthner (1840-1894)].

    PubMed

    Chvátal, A

    2015-01-01

    The works of Jan Evangelista Purkyne, Gabriel Valentin and Robert Remak showed that the nervous system contains not only nerve fibers, but also cellular elements. The use of microscopes and new fixation techniques have enabled the retrieval of accurate data on the structure of nervous tissue and in many European universities microscopes began to be widely used for histological and morphological studies. The present review summarizes the discoveries of the structure of predominantly vertebrate nerve tissue during the period from 1838 to 1865, made by prominent scholars who described the structure of fibers and cells of the nervous system and demonstrated that some nerve fibers are enwrapped by a sheath. In addition, the first attempts were made to make a cytoarchitectonic description of the spinal cord and brain. During the same time the concept of a neuroglial tissue was introduced, first as a tissue for "gluing" nerve fibers, cells and blood capillaries into one unit, but later some glial cells were described for the first time. Microscopic techniques started to be used for examination of physiological as well as pathological nerve tissues. The overall state of knowledge was just a step away from the emergence of the concept of neurons and glial cells. PMID:26852523

  14. Identification of the third type of PVL phage in ST59 methicillin-resistant Staphylococcus aureus (MRSA) strains.

    PubMed

    Zhang, Meng; Ito, Teruyo; Li, Shanshuang; Jin, Jingxun; Takeuchi, Fumihiko; Lauderdale, Tsai-Ling Yang; Higashide, Masato; Hiramatsu, Keiichi

    2011-10-01

    The genes lukS-PV and lukF-PV for Panton-Valentine leukocidin (PVL) that confers high virulence to Staphylococcus aureus are located on the prophages (PVL phages) which have been classified into group 1 and 2 sfi21-like Siphoviridae. We report novel PVL phages lysogenized in ST59 methicillin-resistant Staphylococcus aureus (MRSA) strains isolated in Japan (JCSC7247) and Taiwan (JCSC5967). The genomes of φ7247PVL and φ5967PVL showed more than 99% identity, and the regions containing the five genes located at both ends of the prophages, int (integrase), hol (holin), ami (amidase), lukS-PV, and lukF-PV, are highly homologous to extant PVL phages. The genes for the structural module are less homologous to these phages, but are highly homologous to non-PVL phages belonging to group 3 Sfi21-like Siphoviridae, for example φN315. Subsequent PCR identification and nucleotide sequencing of an additional 11 Taiwanese ST59 MRSA isolates suggested they all carry the same phage as φ5967PVL, which differed from φ7247PVL by a single base. This study adds evidence to the notion that novel PVL phages would be generated through illegitimate recombination events by acquiring the region at which hol, ami, luk, and int genes would line up upon lytic growth, and suggests that the PVL-positive MRSA clones that have emerged worldwide may carry distinct phages. PMID:21732964

  15. Interactions of Methicillin Resistant Staphylococcus aureus USA300 and Pseudomonas aeruginosa in Polymicrobial Wound Infection

    PubMed Central

    Pastar, Irena; Nusbaum, Aron G.; Gil, Joel; Patel, Shailee B.; Chen, Juan; Valdes, Jose; Stojadinovic, Olivera; Plano, Lisa R.; Tomic-Canic, Marjana; Davis, Stephen C.

    2013-01-01

    Understanding the pathology resulting from Staphylococcus aureus and Pseudomonas aeruginosa polymicrobial wound infections is of great importance due to their ubiquitous nature, increasing prevalence, growing resistance to antimicrobial agents, and ability to delay healing. Methicillin-resistant S. aureus USA300 is the leading cause of community-associated bacterial infections resulting in increased morbidity and mortality. We utilized a well-established porcine partial thickness wound healing model to study the synergistic effects of USA300 and P. aeruginosa on wound healing. Wound re-epithelialization was significantly delayed by mixed-species biofilms through suppression of keratinocyte growth factor 1. Pseudomonas showed an inhibitory effect on USA300 growth in vitro while both species co-existed in cutaneous wounds in vivo. Polymicrobial wound infection in the presence of P. aeruginosa resulted in induced expression of USA300 virulence factors Panton-Valentine leukocidin and α-hemolysin. These results provide evidence for the interaction of bacterial species within mixed-species biofilms in vivo and for the first time, the contribution of virulence factors to the severity of polymicrobial wound infections. PMID:23451098

  16. Exploring simvastatin, an antihyperlipidemic drug, as a potential topical antibacterial agent

    PubMed Central

    Thangamani, Shankar; Mohammad, Haroon; Abushahba, Mostafa F. N.; Hamed, Maha I.; Sobreira, Tiago J. P.; Hedrick, Victoria E.; Paul, Lake N.; Seleem, Mohamed N.

    2015-01-01

    The rapid rise of bacterial resistance to traditional antibiotics combined with the decline in discovery of novel antibacterial agents has created a global public health crisis. Repurposing existing drugs presents an alternative strategy to potentially expedite the discovery of new antimicrobial drugs. The present study demonstrates that simvastatin, an antihyperlipidemic drug exhibited broad-spectrum antibacterial activity against important Gram-positive (including methicillin-resistant Staphylococcus aureus (MRSA)) and Gram-negative pathogens (once the barrier imposed by the outer membrane was permeabilized). Proteomics and macromolecular synthesis analyses revealed that simvastatin inhibits multiple biosynthetic pathways and cellular processes in bacteria, including selective interference of bacterial protein synthesis. This property appears to assist in simvastatin’s ability to suppress production of key MRSA toxins (α-hemolysin and Panton-Valentine leucocidin) that impair healing of infected skin wounds. A murine MRSA skin infection experiment confirmed that simvastatin significantly reduces the bacterial burden and inflammatory cytokines in the infected wounds. Additionally, simvastatin exhibits excellent anti-biofilm activity against established staphylococcal biofilms and demonstrates the ability to be combined with topical antimicrobials currently used to treat MRSA skin infections. Collectively the present study lays the foundation for further investigation of repurposing simvastatin as a topical antibacterial agent to treat skin infections. PMID:26553420

  17. Staphylococcus aureus formyl-methionyl transferase mutants demonstrate reduced virulence factor production and pathogenicity.

    PubMed

    Lewandowski, Thomas; Huang, Jianzhong; Fan, Frank; Rogers, Shannon; Gentry, Daniel; Holland, Reannon; Demarsh, Peter; Aubart, Kelly; Zalacain, Magdalena

    2013-07-01

    Inhibitors of peptide deformylase (PDF) represent a new class of antibacterial agents with a novel mechanism of action. Mutations that inactivate formyl methionyl transferase (FMT), the enzyme that formylates initiator methionyl-tRNA, lead to an alternative initiation of protein synthesis that does not require deformylation and are the predominant cause of resistance to PDF inhibitors in Staphylococcus aureus. Here, we report that loss-of-function mutations in FMT impart pleiotropic effects that include a reduced growth rate, a nonhemolytic phenotype, and a drastic reduction in production of multiple extracellular proteins, including key virulence factors, such as α-hemolysin and Panton-Valentine leukocidin (PVL), that have been associated with S. aureus pathogenicity. Consequently, S. aureus FMT mutants are greatly attenuated in neutropenic and nonneutropenic murine pyelonephritis infection models and show very high survival rates compared with wild-type S. aureus. These newly discovered effects on extracellular virulence factor production demonstrate that FMT-null mutants have a more severe fitness cost than previously anticipated, leading to a substantial loss of pathogenicity and a restricted ability to produce an invasive infection. PMID:23571548

  18. The Covariance and Biocovariance of the Stochartic Neutron Field

    SciTech Connect

    Perez, R.B.

    1998-01-01

    The use of stochastic neutron field theory (neutron noise) for the measurement of reactor physics parameters goes back to the early work of Serber, Feynmann, and Orndoff. Since then, a large variety of methods and applications has been developed. In the majority of these methods, some form of modified one-point reactor kinetics was used for the interpretation of the measurements. In fact, the high level of sophistication of the instrumentation used was not matched by the theory. In 1965, Bell developed a general theory of the stochastic neutron field, and in 1987, Munoz-Cobo et al enlarged this treatment to include the effect of the detectors in the neutron field. In both instances, the complexity of the theoretical results were beyond the computing capabilities then available thus, the mismatch between experimental and theoretical methods remained in existence because the powerful Monte-Carlo methods then at work, were only applicable to static neutron fields. This problem was eliminated by the development of a time-dependent Monte-Carlo code specially written by T. E. Valentine for the analysis of stochastic measurements that gave them relevance to the results of the general theory. The purpose of this work is to illustrate the derivation of observables of the stochastic neutron filed from its general treatment.

  19. Targeting Multidrug-resistant Staphylococci with an anti-rpoA Peptide Nucleic Acid Conjugated to the HIV-1 TAT Cell Penetrating Peptide.

    PubMed

    Abushahba, Mostafa Fn; Mohammad, Haroon; Seleem, Mohamed N

    2016-01-01

    Staphylococcus aureus infections present a serious challenge to healthcare practitioners due to the emergence of resistance to numerous conventional antibiotics. Due to their unique mode of action, peptide nucleic acids are novel alternatives to traditional antibiotics to tackle the issue of bacterial multidrug resistance. In this study, we designed a peptide nucleic acid covalently conjugated to the HIV-TAT cell penetrating peptide (GRKKKRRQRRRYK) in order to target the RNA polymerase α subunit gene (rpoA) required for bacterial genes transcription. We explored the antimicrobial activity of the anti-rpoA construct (peptide nucleic acid-TAT) against methicillin-resistant S. aureus, vancomycin-intermediate S. aureus, vancomycin-resistant S. aureus, linezolid-resistant S. aureus, and methicillin-resistant S. epidermidis in pure culture, infected mammalian cell culture, and in an in vivo Caenorhabditis elegans infection model. The anti-rpoA construct led to a concentration-dependent inhibition of bacterial growth (at micromolar concentrations) in vitro and in both infected cell culture and in vivo in C. elegans. Moreover, rpoA gene silencing resulted in suppression of its message as well as reduced expression of two important methicillin-resistant S. aureus USA300 toxins (α-hemolysin and Panton-Valentine leukocidin). This study confirms that rpoA gene is a potential target for development of novel antisense therapeutics to treat infections caused by methicillin-resistant S. aureus. PMID:27434684

  20. Systemic CA-MRSA infection following trauma during soccer match in inner Brazil: clinical and molecular characterization.

    PubMed

    Camargo, Carlos Henrique; da Cunha, Maria de Lourdes Ribeiro de Souza; Bonesso, Mariana Fávero; da Cunha, Fabiana Picoli; Barbosa, Alexandre Naime; Fortaleza, Carlos Magno Castelo Branco

    2013-07-01

    Even though community-acquired methicillin resistant Staphylococcus aureus (CA-MRSA) was described a decade ago, reports from Brazil are scarce and cases occurred in large urban centers. We report MRSA sepsis in a 16-year-old male from a small town and who had no history of exposure to healthcare or recent travel. After trauma during a soccer match, he presented swelling in the right thigh, which evolved in a month to cellulitis complicated by local abscess, orchitis and pneumonia. The patient presented severe sepsis, with fever and respiratory failure. Laboratory findings included blood leukocyte counts above 40,000/mm(3) and thrombocytopenia. He was submitted to mechanical ventilation and therapy with vancomycin and imipenem. He had a slow but favorable response to therapy and was discharged after six weeks of hospitalization. MRSA grew from blood cultures and respiratory aspirates obtained before antimicrobial therapy. The isolate belonged to sequence type 5, spa type t311, harbored SCCmec type IV and genes for Panton-Valentine leukocidin and Enterotoxin A. The pulsed-field gel electrophoresis pattern was distinct from North American classic CA-MRSA clones. However, the sequence type and the spa type revealed that the clone belong to the same clonal complex isolated in Argentina. This is the first CA-MRSA infection reported in that region, with significant epidemiologic and clinical implications. PMID:23602786

  1. Keratinocytes produce IL-6 in response to desmoglein 1 cleavage by Staphylococcus aureus exfoliative toxin A.

    PubMed

    Rolle, Cleo E; Chen, Juan; Pastar, Irena; Cardenas, Tatiana C P; Perez, Roberto; Hower, Suzanne; Ferracci, Franco; Snyder, Richard; Tomic-Canic, Marjana; Plano, Lisa R W

    2013-12-01

    Many skin infections are caused by Staphylococcus aureus, a bacterial pathogen that produces virulence factors associated with these conditions such as exfoliative toxins A and B (ETA, ETB) and the leukotoxin Panton-Valentine leukocidin (PVL). Herein, we examine the potential of skin-infecting S. aureus to produce virulence factors and their impact on the local immune response. Toxin gene profiles were generated from 188 S. aureus isolated as single infecting organisms from skin lesions and demonstrated a higher potential to express ETA, ETB, and PVL than community isolates (p < 0.001). Within the study isolate group, the prevalence of genes encoding PVL was higher among methicillin-resistant S. aureus (MRSA; n = 49), while genes encoding ETs were more prevalent in methicillin-susceptible S. aureus (MSSA; n = 139). When lesion-associated white blood cell (WBC) counts were dichotomized into high- or low-WBC-count-associated bacteria, the gene for ETA was found to be associated with a low WBC count among MSSA (p = 0.001). The ETA-induced mouse model of staphylococcal scalded skin syndrome was used to investigate the link between ETA and cytokine production. Elevated IL-6 levels in the serum and increased expression of IL-6 mRNA in the skin were detected in response to ETA exposure. These findings were recapitulated in vitro using primary human keratinocytes. Thus, S. aureus may influence the local immune response via ETA cleavage of desmoglein 1 and the induction of cutaneous IL-6 expression. PMID:24287883

  2. Species richness in the Phanerozoic: Compensating for sampling bias

    NASA Astrophysics Data System (ADS)

    Signor, Philip W., III

    1982-12-01

    Sampling biases are the greatest impediment to resolving the history of species richness of fossilizable marine invertebrates in the Phanerozoic. Actual patterns of species richness have remained uncertain because no method is available to compensate for variations in sampling intensity. Data are not obtainable which would permit application of techniques that allow direct compensation for sampling intensity, such as rarefaction, but actual patterns can be estimated with a sampling model designed to account for sampling bias. One can estimate the total species richness of a geologic period if one knows the relative sampling intensity devoted to that period, the original species-abundance distribution of all species that existed during the interval, and the number of species that existed during the Cenozoic. The model presented here is based on the assumption that the species-abundance distributions of fossilizable marine invertebrates were lognormal and that sampling was proportional to sediment area, volume, or paleontologist interest units. The model produces consistent results with different estimates of total Cenozoic species richness and sampling intensity and strongly suggests low diversity during the Paleozoic and Mesozoic, followed by a dramatic early Cenozoic increase in standing species richness. These results are consistent with Valentine's (1970) Empirical model of species richness.

  3. International report Finland

    SciTech Connect

    Not Available

    1982-04-01

    The Valentin Shashin, the world's first dynamically positioned ice-class drillship for Arctic conditions, has been completed by Rauma-Repola Oy's Mantyluoto Works in Pori, Finland and delivered to V/O Sudoimport, the Soviet Union. This drillship is the first of three such vessels ordered by the Soviet Union in 1979 for oil exploration in Russia's Arctic waters. All three drillships will be capable of operating in water depths to 300 m and of drilling to 20,000 ft in winds of 23 m/sec, in significant wave heights to 4.7 m and currents to 1 m/sec. Since the vessels are to be used in hostile Arctic conditions, the design incorporates a great deal of sophisticated equipment for operating in heavy seas and avoiding hazards, such as icebergs, that may exist in the drilling area. Included is a quick disconnect system that will allow the ship to detach from the drilling mode in approximately three minutes.

  4. The Physics of Cardiac Fibrillation: Strings that kill

    NASA Astrophysics Data System (ADS)

    Bodenschatz, Eberhard

    2009-03-01

    Fibrillation is a state of spatio-temporal chaos in a 3d-biological excitable medium, namely the heart muscle. The building blocks are wave-emitting three-dimensional topological singularities in the electric excitation field of the tissue. These string like singularities send out a rotating wave fields with very fast frequencies (up to 10 times normal heart rate) and thus dominate over the pacemaker. The incoherent electrical excitation of the spatio-temporal chaotic dynamics leads to an unsynchronized contraction of the cardiac muscle and to the loss of the pumping action, and if untreated to death. Due to the topological nature of the spatio-temporal chaotic state it is very difficult to control. Current defibrillation technologies use strong electric field pulses (1 kV, 30 A, 12 ms) to reset the whole muscle. Here we report that natural muscle heterogeneities act as wave emitting sites when a weak electric field pulse is applied across the tissue. We report theoretical predictions on the physics and support the findings by results from experiment. This work was conducted in collaboration with Stefan Luther (MPIDS), Falvio Fenton ( Cornell), Amgad Squires (Cornell), Robert Gilmour (Cornell), Valentin Krinsky (MPIDS), Alain Pumir (NIce).

  5. Human Staphylococcus aureus lineages among Zoological Park residents in Greece

    PubMed Central

    Drougka, E.; Foka, A.; Posantzis, D.; Giormezis, N.; Anastassiou, E.D.; Petinaki, E.; Spiliopoulou, I.

    2015-01-01

    Staphylococcus aureus is a part of the microbiota flora in many animal species. The clonal spread of S. aureus among animals and personnel in a Zoological Park was investigated. Samples were collected from colonized and infected sites among 32 mammals, 11 birds and eight humans. The genes mecA, mecC, lukF/lukS-PV (encoding Panton-Valentine leukocidin, PVL) and tst (toxic shock syndrome toxin-1) were investigated by PCR. Clones were defined by Multilocus Sequence Typing (MLST), spa type and Pulsed-Field Gel Electrophoresis (PFGE). Seven S. aureus isolates were recovered from four animals and one from an employee. All were mecA, mecC and tst–negative, whereas, one carried the PVL genes and was isolated from an infected Squirrel monkey. Clonal analysis revealed the occurrence of seven STs, eight PFGE and five spa types including ones of human origin. Even though a variety of genotypes were identified among S. aureus strains colonizing zoo park residents, our results indicate that colonization with human lineages has indeed occurred. PMID:26623381

  6. Molecular Types of Methicillin-Resistant Staphylococcus aureus and Methicillin-Sensitive S. aureus Strains Causing Skin and Soft Tissue Infections and Nasal Colonization, Identified in Community Health Centers in New York City.

    PubMed

    Pardos de la Gandara, Maria; Raygoza Garay, Juan Antonio; Mwangi, Michael; Tobin, Jonathan N; Tsang, Amanda; Khalida, Chamanara; D'Orazio, Brianna; Kost, Rhonda G; Leinberger-Jabari, Andrea; Coffran, Cameron; Evering, Teresa H; Coller, Barry S; Balachandra, Shirish; Urban, Tracie; Parola, Claude; Salvato, Scott; Jenks, Nancy; Wu, Daren; Burgess, Rhonda; Chung, Marilyn; de Lencastre, Herminia; Tomasz, Alexander

    2015-08-01

    In November 2011, The Rockefeller University Center for Clinical and Translational Science (CCTS), the Laboratory of Microbiology and Infectious Diseases, and Clinical Directors Network (CDN) launched a research and learning collaborative project with six community health centers in the New York City metropolitan area to determine the nature (clonal type) of community-acquired Staphylococcus aureus strains causing skin and soft tissue infections (SSTIs). Between November 2011 and March 2013, wound and nasal samples from 129 patients with active SSTIs suspicious for S. aureus were collected and characterized by molecular typing techniques. In 63 of 129 patients, the skin wounds were infected by S. aureus: methicillin-resistant S. aureus (MRSA) was recovered from 39 wounds and methicillin-sensitive S. aureus (MSSA) was recovered from 24. Most-46 of the 63-wound isolates belonged to the CC8/Panton-Valentine leukocidin-positive (PVL(+)) group of S. aureus clone USA300: 34 of these strains were MRSA and 12 were MSSA. Of the 63 patients with S. aureus infections, 30 were also colonized by S. aureus in the nares: 16 of the colonizing isolates were MRSA, and 14 were MSSA, and the majority of the colonizing isolates belonged to the USA300 clonal group. In most cases (70%), the colonizing isolate belonged to the same clonal type as the strain involved with the infection. In three of the patients, the identity of invasive and colonizing MRSA isolates was further documented by whole-genome sequencing. PMID:26063853

  7. Recurrent Furunculosis Caused by a Community-Acquired Staphylococcus aureus Strain Belonging to the USA300 Clone

    PubMed Central

    Balachandra, Shirish; Pardos de la Gandara, Maria; Salvato, Scott; Urban, Tracie; Parola, Claude; Khalida, Chamanara; Kost, Rhonda G.; Evering, Teresa H.; Pastagia, Mina; D'Orazio, Brianna M.; Tomasz, Alexander; de Lencastre, Herminia

    2015-01-01

    Background: A 24-year-old female with recurrent skin and soft tissue infections (SSTI) was enrolled as part of a multicenter observational cohort study conducted by a practice-based research network (PBRN) on community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). Methods: Strains were characterized by pulsed-field gel electrophoresis (PFGE), spa typing, and multilocus sequence typing. MRSA strains were analyzed for SCCmec type and the presence of the Panton-Valentine leukocidin (PVL) and arginine catabolic mobile element (ACME) using PCR. Results: In the first episode, S. aureus was recovered from the wound and inguinal folds; in the second, S. aureus was recovered from a lower abdomen furuncle, inguinal folds, and patellar fold. Molecular typing identified CA-MRSA clone USA300 in all samples as spa-type t008, ST8, SCCmecIVa, and a typical PFGE pattern. The strain carried virulence genes pvl and ACME type I. Five SSTI episodes were documented despite successful resolution by antibiotic treatment, with and without incision and drainage. Conclusions: The source of the USA300 strain remains unknown. The isolate may represent a persistent strain capable of surviving extensive antibiotic pressure or a persistent environmental reservoir may be the source, possibly in the patient's household, from which bacteria were repeatedly introduced into the skin flora with subsequent infections. PMID:25668150

  8. A Field Guide to Pandemic, Epidemic and Sporadic Clones of Methicillin-Resistant Staphylococcus aureus

    PubMed Central

    Monecke, Stefan; Coombs, Geoffrey; Shore, Anna C.; Coleman, David C.; Akpaka, Patrick; Borg, Michael; Chow, Henry; Ip, Margaret; Jatzwauk, Lutz; Jonas, Daniel; Kadlec, Kristina; Kearns, Angela; Laurent, Frederic; O'Brien, Frances G.; Pearson, Julie; Ruppelt, Antje; Schwarz, Stefan; Scicluna, Elizabeth; Slickers, Peter; Tan, Hui-Leen; Weber, Stefan; Ehricht, Ralf

    2011-01-01

    In recent years, methicillin-resistant Staphylococcus aureus (MRSA) have become a truly global challenge. In addition to the long-known healthcare-associated clones, novel strains have also emerged outside of the hospital settings, in the community as well as in livestock. The emergence and spread of virulent clones expressing Panton-Valentine leukocidin (PVL) is an additional cause for concern. In order to provide an overview of pandemic, epidemic and sporadic strains, more than 3,000 clinical and veterinary isolates of MRSA mainly from Germany, the United Kingdom, Ireland, France, Malta, Abu Dhabi, Hong Kong, Australia, Trinidad & Tobago as well as some reference strains from the United States have been genotyped by DNA microarray analysis. This technique allowed the assignment of the MRSA isolates to 34 distinct lineages which can be clearly defined based on non-mobile genes. The results were in accordance with data from multilocus sequence typing. More than 100 different strains were distinguished based on affiliation to these lineages, SCCmec type and the presence or absence of PVL. These strains are described here mainly with regard to clinically relevant antimicrobial resistance- and virulence-associated markers, but also in relation to epidemiology and geographic distribution. The findings of the study show a high level of biodiversity among MRSA, especially among strains harbouring SCCmec IV and V elements. The data also indicate a high rate of genetic recombination in MRSA involving SCC elements, bacteriophages or other mobile genetic elements and large-scale chromosomal replacements. PMID:21494333

  9. Characterization of methicillin-resistant Staphylococcus aureus from residents and the environment in a long-term care facility.

    PubMed

    Ludden, C; Brennan, G; Morris, D; Austin, B; O'Connell, B; Cormican, M

    2015-10-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a major public health concern associated with residence in a long-term care facility (LTCF). The aim of this prospective study was to characterize MRSA isolated from residents over a 1-year period and their physical environment over a 2-year period. MRSA was recovered from 17/64 residents (R) of a LTCF and from 42 environmental (E) sites. All isolates carried the mecA gene and lacked the mecC and Panton-Valentine leukocidin (PVL) genes. Thirteen spa types were identified with t032 being the most frequent (41% of total; n = 8R, 16E), followed by t727 (22% of total; n = 13E), and t8783 (10% of total; n = 6E). Five spa types were each represented by single isolates. Thirty-nine isolates were of spa types associated with the multilocus sequence type ST22 (t032, 41%; spa-CC22, 68%) and reflect the predominance of ST22 in Irish hospitals. The uncommon spa types t727, t8783, t1372, t3130, t10038 were present in the environment but not detected in residents and are infrequently observed in Ireland. PMID:25640407

  10. Staphylococcus aureus ST121: a globally disseminated hypervirulent clone.

    PubMed

    Rao, Qing; Shang, Weilong; Hu, Xiaomei; Rao, Xiancai

    2015-12-01

    Staphylococcus aureus is a leading cause of bacterial infections in hospitals and communities worldwide. With the development of typing methods, several pandemic clones have been well characterized, including the extensively spreading hospital-associated meticillin-resistant S. aureus (HA-MRSA) clone ST239 and the emerging hypervirulent community-associated (CA) MRSA clone USA300. The multilocus sequence typing method was set up based on seven housekeeping genes; S. aureus groups were defined by the sharing of alleles at ≥ 5 of the seven loci. In many cases, the predicted founder of a group would also be the most prevalent ST within the group. As a predicted founder of major S. aureus groups, approximately 90 % of ST121 strains was meticillin-susceptible S. aureus (MSSA). The majority of ST121 strains carry accessory gene regulator type IV, whereas staphylococcal protein A gene types for ST121 are exceptionally diverse. More than 90 % of S. aureus ST121 strains have Panton-Valentine leukocidin; other enterotoxins, haemolysins, leukocidins and exfoliative toxins also contribute to the high virulence of ST121 strains. Patients suffering from S. aureus ST121 infections often need longer hospitalization and prolonged antimicrobial therapy. In this review, we tried to summarize the epidemiology of the S. aureus clone ST121 and focused on the molecular types, toxin carriage and disease spectrum of this globally disseminated clone. PMID:26445995

  11. High-resolution melting analysis of the spa locus reveals significant diversity within sequence type 93 methicillin-resistant Staphylococcus aureus from northern Australia.

    PubMed

    Tong, S Y C; Lilliebridge, R A; Holt, D C; McDonald, M I; Currie, B J; Giffard, P M

    2009-12-01

    High-resolution melting analysis is an inherently robust, easy and inexpensive approach to the examination of genomic regions containing single-nucleotide polymorphisms and hypervariable loci. Staphylococcus aureus sequence type (ST) 93 is a singleton, Panton-Valentine leukocidin-positive clone unique to Australia. A high-resolution melting-based method for the identification of ST93 was developed, and a similar approach was used to reveal diversity within the spa locus of this lineage. Statistical and graphical methods that account for instrumental and operator-dependent variation in high-resolution melting curves were developed, to allow greater confidence and reproducibility in deciding whether another curve is truly different from the baseline curve of an amplicon with known sequence. The data support a very early acquisition, or multiple independent acquisitions, of SCCmec by ST93 methicillin-susceptible S. aureus (MSSA), and the coexistence of MSSA and methicillin-resistant S. aureus versions of the same lineage within northern Australia. PMID:19392885

  12. Staphylococcus aureus Formyl-Methionyl Transferase Mutants Demonstrate Reduced Virulence Factor Production and Pathogenicity

    PubMed Central

    Lewandowski, Thomas; Huang, Jianzhong; Fan, Frank; Rogers, Shannon; Gentry, Daniel; Holland, Reannon; DeMarsh, Peter; Zalacain, Magdalena

    2013-01-01

    Inhibitors of peptide deformylase (PDF) represent a new class of antibacterial agents with a novel mechanism of action. Mutations that inactivate formyl methionyl transferase (FMT), the enzyme that formylates initiator methionyl-tRNA, lead to an alternative initiation of protein synthesis that does not require deformylation and are the predominant cause of resistance to PDF inhibitors in Staphylococcus aureus. Here, we report that loss-of-function mutations in FMT impart pleiotropic effects that include a reduced growth rate, a nonhemolytic phenotype, and a drastic reduction in production of multiple extracellular proteins, including key virulence factors, such as α-hemolysin and Panton-Valentine leukocidin (PVL), that have been associated with S. aureus pathogenicity. Consequently, S. aureus FMT mutants are greatly attenuated in neutropenic and nonneutropenic murine pyelonephritis infection models and show very high survival rates compared with wild-type S. aureus. These newly discovered effects on extracellular virulence factor production demonstrate that FMT-null mutants have a more severe fitness cost than previously anticipated, leading to a substantial loss of pathogenicity and a restricted ability to produce an invasive infection. PMID:23571548

  13. A Study of Sympathetic Flaring Using a Full-Sun Event Catalog

    NASA Astrophysics Data System (ADS)

    Higgins, P. A.; Schrijver, C. J.; Title, A. M.; Bloomfield, D.; Gallagher, P.

    2013-12-01

    There has been a trove of papers published on the statistics of flare occurrence. These studies are trying to answer the question of whether or not subsequent solar flares are related. The majority of these works have not included both flare location information and the physical properties of the regions responsible for the eruptions, and none have taken advantage of full-Sun event coverage. Now that SDO/AIA is available and the STEREO spacecraft have progressed past 90 degrees from Earth's heliographic longitude, this new information is available to us. This work aims to quantify how common sympathetic events are, and how important they are in the forecasting of solar flares. A 3D plot of detected and clustered flare events for a full solar rotation, including the Valentine's Day Event of 2011. A full-Sun image in the EUV (304A) including both STEREO view points and AIA. The GOES X-ray light curves during the February period of 2011 are shown in the bottom panel. Detected flare events are indicated by the green dashed lines and the time stamp of this image is denoted by the red line.

  14. Selenium levels and Glutathione peroxidase activity in the plasma of patients with type II diabetes mellitus.

    PubMed

    González de Vega, Raquel; Fernández-Sánchez, María Luisa; Fernández, Juan Carlos; Álvarez Menéndez, Francisco Vicente; Sanz-Medel, Alfredo

    2016-09-01

    Selenium, an essential trace element, is involved in the complex system of defense against oxidative stress through selenium-dependent glutathione peroxidases (GPx) and other selenoproteins. Because of its antioxidant properties, selenium or its selenospecies at appropriate levels could hinder oxidative stress and so development of diabetes. In this vein, quantitative speciation of selenium in human plasma samples from healthy and diabetic patients (controlled and non-controlled) was carried out by affinity chromatography (AF) coupled on-line to inductively coupled plasma mass spectrometry (ICP-MS) and isotope dilution analysis (IDA). Similarly, it is well known that patients with diabetes who exhibit poor control of blood glucose show a decreased total antioxidant activity. Thus, we evaluated the enzymatic activity of GPx in diabetic and healthy individuals, using the Paglia and Valentine enzymatic method, observing a significant difference (p<0.05) between the three groups of assayed patients (healthy (n=24): 0.61±0.11U/ml, controlled diabetic (n=38): 0.40±0.12U/ml and non-controlled diabetic patients (n=40): 0.32±0.09U/ml). Our results show that hyperglycemia induces oxidative stress in diabetic patients compared with healthy controls. What is more, glycation of GPx experiments demonstrated that it is the degree of glycation of the selenoenzyme (another species of the Se protein) what actually modulates its eventual activity against ROS in type II diabetes mellitus patients. PMID:27473831

  15. Reminders Through Association.

    PubMed

    Rogers, Todd; Milkman, Katherine L

    2016-07-01

    People often fail to follow through on good intentions. While limited self-control is frequently the culprit, another cause is simply forgetting to enact intentions when opportunities arise. We introduce a novel, potent approach to facilitating follow-through: the reminders-through-association approach. This approach involves associating intentions (e.g., to mail a letter on your desk tomorrow) with distinctive cues that will capture attention when you have opportunities to act on those intentions (e.g., Valentine's Day flowers that arrived late yesterday, which are sitting on your desk). We showed that cue-based reminders are more potent when the cues they employ are distinctive relative to (a) other regularly encountered stimuli and (b) other stimuli encountered concurrently. Further, they can be more effective than written or electronic reminder messages, and they are undervalued and underused. The reminders-through-association approach, developed by integrating and expanding on past research on self-control, reminders, and prospective memory, can be a powerful tool for policymakers and individuals. PMID:27207873

  16. Strawberry Cultivars Vary in their Resistance to Northern Lesion Nematode

    PubMed Central

    Dale, Adam; Potter, John W.

    1998-01-01

    The genetic diversity of commercial cultivars of strawberry Fragaria x ananassa from various parentages, as expressed by their resistance to the northem lesion nematode Pratylenchus penetrans, was evaluated in nematode-infested field plots for two growing seasons. Data taken for each plant in each season included soil nematode Pi and Pf, end-of-season nematode numbers in each entire root system, and end-of-season fresh and dry top weight and whole root system weight. Resistance was estimated using an index of the nematode load on the plant: Nematode load = {n(root) + (200 × n[soil])}/{root dry weight} where n (root) = number of nematodes in the root, n [soil] = number of nematodes in 50 g of nonfumigated soil, and 200 is a multiplier to convert the soil nematode count to a 10-kg basis. Nineteen strawberry cultivars varied in their resistance to the northern lesion nematode, from a mean load of 382 nematodes/plant for Pajaro to 1,818 nematodes/plant for Veestar. This variability could be related to the original family groupings, with the most resistant cultivars related to Lassen and the least resistant to Sparkle x Valentine. PMID:19274249

  17. European National Society Cardiovascular Journals

    PubMed Central

    Alfonso, F.; Ambrosio, G.; Pinto, F.J.; van der Wall, E.E.

    2008-01-01

    Anesti Kondili MD, Djamaleddine Nibouche MD, Karlen Adamyan MD, Kurt Huber MD, Hugo Ector MD, Izet Masic MD, Rumiana Tarnovska MD, Mario Ivanusa MD, Vladimír Stane˘k MD, Jørgen Videbæk MD, Mohamed Hamed MD, Alexandras Laucevicius MD, Pirjo Mustonen MD, Jean-Yves Artigou MD, Ariel Cohen MD, Mamanti Rogava MD, Michael Böhm MD, Eckart Fleck MD, Gerd Heusch MD, Rainer Klawki MD, Panos Vardas MD, Christodoulos Stefanadis MD, József Tenczer MD, Massimo Chiariello MD, Aleksandras Laucevicius MD, Joseph Elias MD, Halima Benjelloun MD, Olaf Rødevand MD, Piotr Kul/akowski MD, Edvard Apetrei MD, Victor A. Lusov MD, Rafael G. Oganov MD, Velibor Obradovic MD, Gabriel Kamensky MD, Miran F. Kenda MD, Christer Höglund MD, Thomas F. Lüscher MD, René Lerch MD, Moufid Jokhadar MD, Habib Haouala MD, Vedat Sansoy MD, Valentin Shumakov MD, Adam Timmis MD. (European National Society Cardiovascular Journals Editors, see Appendix for complete affiliations) PMID:18665206

  18. Emergence of the community-acquired methicillin-resistant Staphylococcus aureus USA300 clone in a Japanese child, demonstrating multiple divergent strains in Japan.

    PubMed

    Higuchi, Wataru; Mimura, Shigenao; Kurosawa, Yoshihiro; Takano, Tomomi; Iwao, Yasuhisa; Yabe, Shizuka; Razvina, Olga; Nishiyama, Akihito; Ikeda-Dantsuji, Yurika; Sakai, Fuminori; Hanaki, Hideaki; Yamamoto, Tatsuo

    2010-08-01

    In 2008 we isolated methicillin-resistant Staphylococcus aureus (MRSA) from an 11-month-old Japanese girl who lived in Saitama, Japan, and suffered from cellulitis of the lower thigh and sepsis. The MRSA (strain NN47) belonged to multilocus sequence type (ST) 8 and exhibited spa363 (t024), agr1, staphylococcal cassette chromosome mec (SCCmec) type IVa, and coagulase type III. It was positive for Panton-Valentine leukocidin (PVL) and the arginine catabolic mobile element (ACME). Pulsed-field gel electrophoresis (PFGE) demonstrated that the MRSA was the USA300 clone, which is the predominant community-acquired MRSA (CA-MRSA) in the US. Strain NN47 was divergent, in terms of the spa type and patterns of PFGE and plasmids, from the USA300-0114 type strain or USA300 strain NN36, previously isolated from a visitor (Indian girl) from the US. Strain NN47 was resistant to erythromycin, in addition to beta-lactam agents (e.g., oxacillin). These data demonstrate the first emergence of the USA300 clone in Japanese children who have never been abroad and have had no contact with foreigners (and therefore, the first USA300 spread in Japan), and also emergence of multiple divergent strains of the USA300 clone in Japan. Because the USA300 clone is highly transmissible and virulent, surveillance of the USA300 clone is needed. PMID:20306108

  19. Spread of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) in hospitals in Taipei, Taiwan in 2005, and comparison of its drug resistance with previous hospital-acquired MRSA.

    PubMed

    Takano, Tomomi; Saito, Kohei; Teng, Lee-Jene; Yamamoto, Tatsuo

    2007-01-01

    Panton-Valentine leucocidin (PVL)-positive methicillin-resistant Staphylococcus aureus (PVL+ MRSA) is an emerging pathogen in the community worldwide. The incidence of PVL+ MRSA in Taipei, Taiwan was 23.3% for hospital MRSA. PVL+ MRSA was isolated from both outpatients and inpatients. Some PVL+ (mecA+) strains (36.8%) showed low MIC values (

  20. Superior in vitro activity of carbapenems over anti-methicillin-resistant Staphylococcus aureus (MRSA) and some related antimicrobial agents for community-acquired MRSA but not for hospital-acquired MRSA.

    PubMed

    Takano, Tomomi; Higuchi, Wataru; Yamamoto, Tatsuo

    2009-02-01

    Eighty-eight strains of Panton-Valentine leukocidin (PVL)-positive and -negative community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) and 152 strains of hospital-acquired MRSA (HA-MRSA) were examined for susceptibility to carbapenems, oxacillin, and other antimicrobial agents. CA-MRSA strains were more susceptible to carbapenems (MIC(90), 1-4 microg/ml) than HA-MRSA strains (MIC(90), 32-64 microg/ml). Among the carbapenems examined, CA-MRSA strains were most susceptible to imipenem (MIC(50), 0.12 microg/ml; MIC(90), 1 microg/ml). A similar tendency was observed with oxacillin, but less markedly (MIC(90): 32 microg/ml for CA-MRSA and > or =256 microg/ml for HA-MRSA). This difference was also observed between CA-MRSA and HA-MRSA in susceptibility levels to cephems, erythromycin, clindamycin, and levofloxacin, but not to ampicillin, vancomycin, teicoplanin, linezolid, and arbekacin. The data indicate that, in terms of MIC(50) or MIC(90) values, CA-MRSA is 64-256 times more susceptible to imipenem than HA-MRSA, and for CA-MRSA, some carbapenems, e.g., imipenem, show better in vitro activity than anti-MRSA or some related agents. PMID:19280303

  1. Current concepts on the virulence mechanisms of meticillin-resistant Staphylococcus aureus

    PubMed Central

    David, Michael Z.; Salata, Robert A.

    2012-01-01

    Meticillin-resistant Staphylococcus aureus (MRSA) strains are prevalent bacterial pathogens that cause both health care and community-associated infections. Increasing resistance to commonly prescribed antibiotics has made MRSA a serious threat to public health throughout the world. The USA300 strain of MRSA has been responsible for an epidemic of community-associated infections in the US, mostly involving skin and soft tissue but also more serious invasive syndromes such as pneumonia, severe sepsis and endocarditis. MRSA strains are particularly serious and potentially lethal pathogens that possess virulence mechanisms including toxins, adhesins, enzymes and immunomodulators. One of these is Panton–Valentine leukocidin (PVL), a toxin associated with abscess formation and severe necrotizing pneumonia. Earlier studies suggested that PVL was a major virulence factor in community-associated MRSA infections. However, some recent data have not supported this association while others have, leading to controversy. Therefore, investigators continue to search for additional mechanisms of pathogenesis. In this review, we summarize the current understanding of the biological basis of MRSA virulence and explore future directions for research, including potential vaccines and antivirulence therapies under development that might allow clinicians to more successfully treat and prevent MRSA infections. PMID:22745137

  2. Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) at ambient freshwater beaches

    USGS Publications Warehouse

    Fogarty, Lisa R.; Haack, Sheridan K.; Johnson, Heather E.; Brennan, Angela K.; Isaacs, Natasha M.; Spencer, Chelsea

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) are a threat to human health worldwide, and although detected at marine beaches, they have been largely unstudied at freshwater beaches. Genes indicating S. aureus (SA; femA) and methicillin resistance (mecA) were detected at 11 and 12 of 13 US Great Lakes beaches and in 18% or 27% of 287 recreational water samples, respectively. Eight beaches had mecA + femA (potential MRSA) detections. During an intensive study, higher bather numbers, staphylococci concentrations, and femA detections were found in samples collected after noon than before noon. Local population density, beach cloud cover, and beach wave height were significantly correlated with SA or MRSA detection frequency. The Panton-Valentine leukocidin gene, associated with community-acquired MRSA, was detected in 12 out of 27 potential MRSA samples. The femA gene was detected less frequently at beaches that met US enterococci criteria or EU enterococci ‘excellent’ recreational water quality, but was not related to Escherichia coli-defined criteria. Escherichia coli is often the only indicator used to determine water quality at US beaches, given the economic and healthcare burden that can be associated with infections caused by SA and MRSA, monitoring of recreational waters for non-fecal bacteria such as staphylococci and/or SA may be warranted.

  3. A Big Year for Small Bodies

    NASA Astrophysics Data System (ADS)

    Mayo, Louis; Erickson, K.

    2013-10-01

    2013 is a watershed year for celestial events involving the solar system’s unsung heroes, small bodies. The Cosmic Valentine of Asteroid 2012 DA14 which passed within ~ 3.5 Earth radii of the Earth's surface (February 15, 2013), Comet C/2011 L4 PANSTARRS and the Thanksgiving 2013 pass of Comet ISON, which will pass less than 0.012 AU (1.8 million km) from the solar surface and could be visible during the day. All this in addition to Comet Lemmon and a host of meteor showers makes 2013 a landmark year to deliver the excitement of planetary science to the audiences worldwide. To deliver the excitement and wonder of our solar system’s small bodies to worldwide audiences, NASA’s JPL and GSFC education teams in partnership with NASA EDGE will reach out to the public through multiple venues including broadcast media, social media, science and math focused educational activities, observing challenges, interactive visualization tools like “Eyes on the Solar System” and more culminating in the Thanksgiving Day Comet ISON perihelion passage. This talk will highlight NASA’s focused education effort to engage the public in small bodies science and the role these objects play in our understanding of the formation and evolution of the solar system.

  4. Evolution and pathogenesis of Staphylococcus aureus: lessons learned from genotyping and comparative genomics.

    PubMed

    Feng, Ye; Chen, Chih-Jung; Su, Lin-Hui; Hu, Songnian; Yu, Jun; Chiu, Cheng-Hsun

    2008-01-01

    Staphylococcus aureus is an opportunistic pathogen and the major causative agent of numerous hospital- and community-acquired infections. Multilocus sequence typing reveals a highly clonal structure for S. aureus. Although infrequently occurring across clonal complexes, homologous recombination still contributed to the evolution of this species over the long term. agr-mediated bacterial interference has divided S. aureus into four groups, which are independent of clonality and provide another view on S. aureus evolution. Genome sequencing of nine S. aureus strains has helped identify a number of virulence factors, but the key determinants for infection are still unknown. Comparison of commensal and pathogenic strains shows no difference in diversity or clonal assignments. Thus, phage dynamics and global transcriptome shifts are considered to be responsible for the pathogenicity. Community-acquired methicillin-resistant S. aureus (C-MRSA) is characterized by a short SCCmec and the presence of a Panton-Valentine leukocidin locus, but no studies have proven their exact biologic roles in C-MRSA infection, indicating the existence of other mechanisms for the genesis of C-MRSA. PMID:17983441

  5. [Antiparacelism and Trinity: medical antitrinitarism from Thomas Erastus (1524-1583) to Ernst Soner (1572-1605)].

    PubMed

    Bröer, Ralf

    2006-06-01

    There were close relationships between Renaissance medicine and antitrinitarianism in 16th and 17th century. Forming an important part of the radical reformation antitrinitarianism won many disciples in the Holy Roman Empire and proved its attraction for physicians. This paper centers on two public scandals in Heidelberg and Altdorf involving the reknown university professors and physicians Thomas Erastus and Ernst Soner. Michael Servetus' new concept of the blood flow through the lungs was discussed in Heidelberg. In Altdorf Caspar Hofmann, Soner's colleague, developed a special theory of the blood flow and corresponded with William Harvey. Erastus and Soner sharply critisized the hermectical and neoplatonical ideas of Paracelsus. Although sympathizing with antitrinitarianism they denounced the Paracelsians as heretics. The Polish antitrinitarians were called Socinians, from Faustus Socinus. Their doctrine tended to be Aristotelic and rationalistic. Soner combined a socinian theology with a heterodox Aristotelianism referring to Andrea Cesalpino. Again after Soner's death some of his pupils and other physicians advocated socinianism in Gdansk (Martin Ruar, Florian Krause, Daniel Zwicker, Valentin Baumgart). PMID:17147155

  6. Human Monocyte-Derived Osteoclasts Are Targeted by Staphylococcal Pore-Forming Toxins and Superantigens

    PubMed Central

    Flammier, Sacha; Rasigade, Jean-Philippe; Badiou, Cédric; Henry, Thomas; Vandenesch, François; Laurent, Frédéric; Trouillet-Assant, Sophie

    2016-01-01

    Staphylococcus aureus is the leading cause of bone and joint infections (BJIs). Staphylococcal pathogenesis involves numerous virulence factors including secreted toxins such as pore-forming toxins (PFTs) and superantigens. The role of these toxins on BJI outcome is largely unknown. In particular, few studies have examined how osteoclasts, the bone-resorbing cells, respond to exposure to staphylococcal PFTs and superantigens. We investigated the direct impact of recombinant staphylococcal toxins on human primary mature monocyte-derived osteoclasts, in terms of cytotoxicity and cell activation with cell death and bone resorption assays, using macrophages of the corresponding donors as a reference. Monocyte-derived osteoclasts displayed similar toxin susceptibility profiles compared to macrophages. Specifically, we demonstrated that the Panton-Valentine leukocidin, known as one of the most powerful PFT which lyses myeloid cells after binding to the C5a receptor, was able to induce the death of osteoclasts. The archetypal superantigen TSST-1 was not cytotoxic but enhanced the bone resorption activity of osteoclasts, suggesting a novel mechanism by which superantigen-producing S. aureus can accelerate the destruction of bone tissue during BJI. Altogether, our data indicate that the diverse clinical presentations of BJIs could be related, at least partly, to the toxin profiles of S. aureus isolates involved in these severe infections. PMID:26934588

  7. [Tinea capitis profunda due to Trichophyton verrucosum with cMRSA superinfection in an infant].

    PubMed

    Blömer, R-H; Keilani, N; Faber, A; Rodeck, B; Krüger, C; Uhrlaß, S; Gräser, Y; Nenoff, P

    2012-08-01

    A 28-month-old boy developed a cutaneous and subcutaneous lesion of the scalp together with alopecia. Treatment with sulfadiazine silver ointment and oral administration of cefaclor failed. The boy lived on a farm where cows and calves were present. He presented with a 5 cm erythematous, erosive, edematous, and sharply defined lesion with yellow crusts and circumscribed alopecia on the temporoparietal scalp. Peripheral hairs were easily epilated. Swabs from the wound revealed cMRSA (community acquired methicillin-resistant Staphylococcus aureus, Panton Valentine Leukocidin [PVL] toxin negative). There was no improvement after treatment with cefuroxime intravenously over 3 days. Therapy was changed to vancomycin and fosfomycin. Because of the purulent abscess, surgical incision was performed. PCR (polymerase chain reaction)-Elisa assay detected Trichophyton (T.) interdigitale-DNA from wound secretion and skin biopsy. Because of the clinical and molecular diagnosis of tinea capitis, oral antifungal therapy with fluconazole 5 mg kg(-1) body weight was started, along with cotrimoxazole and fosfomycin for the cMRSA. After 4 weeks incubation, the causative agent T. verrucosum was grown on culture and its identity confirmed by sequencing of the "internal transcribed spacer" (ITS) region of the ribosomal DNA. After 4 weeks of fluconazole, the lesion was nearly healed. PMID:22406762

  8. Molecular characterization of Staphylococcus aureus isolates from skin and soft tissue infections samples and healthy carriers in the Central Slovenia region.

    PubMed

    Svent-Kucina, Natasa; Pirs, Mateja; Kofol, Romina; Blagus, Rok; Smrke, Dragica Maja; Bilban, Marjan; Seme, Katja

    2016-04-01

    Staphylococcus aureus is among the most important human pathogens. It is associated with different infections and is a major cause of skin and soft tissue infections (SSTIs). The aim of our study was to compare S. aureus isolates associated with SSTIs with isolates obtained from healthy carriers in the Central Slovenia region in terms of antimicrobial susceptibility, genetic diversity by clonal complex (CC)/sequence type, spa type, and by toxin gene profiling. In total, 274 S. aureus isolates were collected prospectively by culturing wound samples from 461 SSTI patients and nasal samples from 451 healthy carriers. We have demonstrated high heterogeneity in terms of CCs and spa type in both groups of isolates. The main clone among SSTI strains was Panton-Valentine leukocidin gene (pvl) positive CC121, whereas the main clone among carrier strains was CC45 carrying a large range of toxin genes. The main spa type in both groups was t091. Pvl was more frequently present in SSTI strains (31.2% SSTI vs 3.6% carrier strains) and staphylococcal enterotoxin C was more frequently present in carrier strains (1.6% SSTI vs 17.0% carrier strains). We have also demonstrated that methicillin-resistant S. aureus was a rare cause (2.8%) of SSTIs in our region. PMID:26781044

  9. Molecular characterization of methicillin-resistant Staphylococcus aureus: characterization of major clones and emergence of epidemic clones of sequence type (ST) 36 and ST 121 in Tehran, Iran.

    PubMed

    Ohadian Moghadam, Solmaz; Pourmand, Mohammad Reza; Mahmoudi, Mahmood; Sadighian, Hooman

    2015-04-01

    Information about the molecular structure of MRSA strains provides significant insights into the epidemiology of this important pathogen. To investigate the molecular characteristics of MRSA isolates, MRSA isolates were subjected to molecular typing by means of spa typing, multilocus sequence typing, Staphylococcal Cassette Chromosome mec (SCCmec) grouping and to phenotypic antimicrobial susceptibility testing by means of disk diffusion assay. Then the presence of pvl genes was evaluated. Cluster analysis by eBURSTv3 showed that MRSA isolates belonged to two major clonal complexes (CC); CC8 (ST239, ST585, ST2732, ST1294) and CC30 (ST30, ST36, ST1163) and four singletons. Subsequent analysis of MRSA isolates revealed that the most prevalent SCCmec type was type III (55.8%) followed by type IV (34.9%) and type II (2.3%). Totally 11 different spa types were discriminated among which types t037 and t030 were predominant. The prevalence of Panton-Valentine leukocidin (PVL)-positive MRSA strains was high (20%), which is a matter of great concern, because the PVL is frequently associated with severe and recurrent SSTIs. ST239-III- t037 represented the most predominant MRSA clone. The presence of sequence type (ST) 36 and ST 121 are being reported for the first time in Iran. PMID:25795589

  10. Epidemiology of Staphylococcus aureus in Bangalore, India: emergence of the ST217 clone and high rate of resistance to erythromycin and ciprofloxacin in the community

    PubMed Central

    Bouchiat, C.; El-Zeenni, N.; Chakrakodi, B.; Nagaraj, S.; Arakere, G.; Etienne, J.

    2015-01-01

    This study aimed to determine the antibiotic susceptibility pattern of Staphylococcus aureus (SA) and the circulating clones in Bangalore, India. Susceptibility testing was performed for all cases of SA infections in a tertiary-care hospital. Panton-Valentine leucocidin (PVL) encoding genes were detected, and sequence type and spa type were determined. Out of the 92 collected strains, 52.2% were methicillin-resistant SA (MRSA), isolated from community-acquired (CA) infections in 60.4% and hospital-acquired (HA) infections in 39.6%. S. aureus isolates were also highly resistant to erythromycin (54.3%) and ciprofloxacin (70.6%) in methicillin-susceptible SA (MSSA) and MRSA, as well as in CA and HA infections. MRSA were found to be significantly more resistant to gentamicin (p <0.001), cotrimoxazole (p <0.001) and ciprofloxacin (p 0.001) than MSSA, but no significant difference was observed between CA- and HA-SA. ST217 appeared as a new emerging and prevalent clone, but ST772 remained the predominant clone, all being PVL-positive isolates. Our study points out the high prevalence of MRSA, even in the community, and the worrying increase of resistance to ciprofloxacin and erythromycin among CA-MSSA. Emergence of clone ST217 is reported for the first time in India. PMID:26110062

  11. Mate preferences do predict attraction and choices in the early stages of mate selection.

    PubMed

    Li, Norman P; Yong, Jose C; Tov, William; Sng, Oliver; Fletcher, Garth J O; Valentine, Katherine A; Jiang, Yun F; Balliet, Daniel

    2013-11-01

    Although mate preference research has firmly established that men value physical attractiveness more than women do and women value social status more than men do, recent speed-dating studies have indicated mixed evidence (at best) for whether people's sex-differentiated mate preferences predict actual mate choices. According to an evolutionary, mate preference priority model (Li, Bailey, Kenrick, & Linsenmeier, 2002; Li & Kenrick, 2006; Li, Valentine, & Patel, 2011), the sexes are largely similar in what they ideally like, but for long-term mates, they should differ on what they most want to avoid in early selection contexts. Following this model, we conducted experiments using online messaging and modified speed-dating platforms. Results indicate that when a mating pool includes people at the low end of social status and physical attractiveness, mate choice criteria are sex-differentiated: Men, more than women, chose mates based on physical attractiveness, whereas women, more than men, chose mates based on social status. In addition, individuals who more greatly valued social status or physical attractiveness on paper valued these traits more in their actual choices. In particular, mate choices were sex-differentiated when considering long-term relationships but not short-term ones, where both sexes shunned partners with low physical attractiveness. The findings validate a large body of mate preferences research and an evolutionary perspective on mating, and they have implications for research using speed-dating and other interactive contexts. PMID:23915041

  12. Tlazolteotl, the Aztec goddess of epilepsy.

    PubMed

    Ladino, Lady Diana; Téllez-Zenteno, José Francisco

    2016-04-01

    Epilepsy has afflicted humanity during most of the extent of documented history. The Aztecs believed that illnesses were punishments that were sent from a furious goddess. In particular, epilepsy was considered in Aztec culture as a "sacred disease", and convulsions were traditionally associated with a deified woman who had died at childbirth. As the goddess Shiva and Apasmâra in ancient India and Saint Valentine in Germany, Tlazolteotl was considered able to bring about and send away epilepsy. We performed a comprehensive review to identify Tlazolteotl depictions and its historical context related with epilepsy. Tlazolteotl is one of the most endearing and complex goddesses of the Mesoamericans. She was the deity of the black fertile and fecund earth that gains its energy from death and in turn feeds life. Associated with purification, expiation, and regeneration, she embodied fertility and turned all garbage, physical and metaphysical, into rich life. This article reviews the most relevant artistic works related with Tlazolteotl. We also present a modern depiction of the Aztec goddess of epilepsy from the Mexican artist Eduardo Urbano Merino, displaying the supernatural view of epilepsy in America. PMID:26921600

  13. The GNSS network at Piton de la Fournaise

    NASA Astrophysics Data System (ADS)

    Staudacher, Thomas; Peltier, Aline; Boissier, Patrice; Di Muro, Andrea; Kowalski, Philippe; Lauret, Frederic

    2013-04-01

    The Piton de la Fournaise volcano at La Réunion Island in the western Indian Ocean is amongst the most active volcanoes in the world with a mean over 2 centuries of one eruption every 9 month. Since 1998 up to 4 eruptions occurred per year. The volcanological observatory, which is a branch of the Institut de Physique du Globe de Paris, is in charge of the monitoring of the volcanic activity and the prediction of eruptions by means of several networks: deformation, seismicity and gas emission. We will focus here on the GNSS network. The permanent GNSS network consist in 25 stations, 5 stations around the summit craters "Bory" and "Dolomieu", 5 stations at the base of the central cone at about 2 km away from the summit, 6 stations on the eastern flank in the Grandes Pentes and Grand Brûlé area. Two stations are situated north and south outside of the Enclos Fouqué Caldera. Four basis stations are situated farther away outside of the caldera Fouqué at high and low elevation. Very first GPS measurements at Piton de la Fournaise were attempted since 1994 between Bory (BORG) and "Enclos Zéro" (ENCG). The present permanent network was built up since 2004; the central network, covering the volcanic cone was upgraded till 2006. Between end 2009 and early 2010 the eastern flank, which is difficult to access, was equipped in the frame of the "Undervolc program". Data acquisition is usually done every 30 seconds, but can be incremented to 1Hz and even to 20 Hz for the most recent NetR9 receivers. Data files were transmitted by radio every day and evaluated. Presently we move the daily evaluation of the data from Winprism to Gamit, which shows in some cases more precise results, in particular when we compare stations at low and high elevation. The cinematic GPS network consist today in 78 sites, equipped with stainless steel rods cemented in the rock or fixed on metallic tripods. These sites are measured routinely one or two times per year, or more often in case of

  14. Effective Theories Of The Strong Interaction

    SciTech Connect

    Dr. Ubirajara van Kolck

    2004-07-31

    This is the final report corresponding to the full funding period (08/01-07/04) in the Department of Energy Outstanding Junior Investigator Grant DE-FG03-01ER41196. The development of an understanding of the interplay between perturbative and non-perturbative effects in strong-interacting systems forms the broad context of this research. The main thrust is the application of effective theories to QCD. Topics included a new power counting in the pionful effective theory, low-energy Compton scattering, charge-symmetry breaking in pion production and in the two-nucleon potential, parity violation, coupled-channel scattering, shallow resonances and halo nuclei, chiral symmetry in the baryon spectrum, existence of a tetraquark state, and molecular meson states. DOE grant DE-FG03-01ER41196 was used to partially support in the period 08/01-07/04 the research activities of the Principal Investigator, Dr. Ubirajara van Kolck, one post-doctoral research associate, Dr. Boris A. Gelman, and one graduate student, Mr. Will Hockings. During the grant period the PI was first Assistant then Associate Professor of Physics at the University of Arizona (UA), and a RHIC Physics Fellow at the RIKEN-BNL Research Center (RBRC). The association with RBRC ended in the Summer of 2004. Since September of 2002 the PI has also been partially supported by a Sloan Research Fellowship. Dr. Boris Gelman was supported by the grant from September 2002 to May 2004. He joined the UA after receiving a Ph.D. from the University of Maryland in the Summer of 2002. He left to take a research associate position in the nuclear theory group of the State University of New York at Stony Brook. The support of a post-doctoral researcher on this grant for two years was only possible by carrying over first- and second-year funds to later years. In addition, Mr. William Hockings started doing research under the PI's guidance. Mr. Hockings took Independent Study courses with the PI, while working as a teaching

  15. Lift outs: how to acquire a high-functioning team.

    PubMed

    Groysberg, Boris; Abrahams, Robin

    2006-12-01

    More and more, expanding companies are hiring high-functioning groups of people who have been working together effectively within one company and can rapidly come up to speed in a new environment. These lifted-out teams don't need to get acquainted with one another or to establish shared values, mutual accountability, or group norms; their long-standing relationships and trust help them make an impact very quickly. Of course, the process is not without risks: A failed lift out can lead to loss of money, opportunity, credibility, and even native talent. Boris Groysberg and Robin Abrahams studied more than 40 high-profile moves and interviewed team leaders in multiple industries and countries to examine the risks and opportunities that lift outs present. They concluded that, regardless of industry, nationality, or size of the team, a successful lift out unfolds over four consecutive, interdependent stages that must be meticulously managed. In the courtship stage, the hiring company and the leader of the targeted team determine whether the proposed move is, in fact, a good idea, and then define their business goals and discuss strategies. At the same time, the team leader discusses the potential move with the other members of his or her group to assess their level of interest and prepare them for the change. The second stage involves the integration of the team leader with the new company's top leadership. This part of the process ensures the team's access to senior executives-the most important factor in a lift out's success. Operational integration is the focus of the third stage. Ideally, teams will start out working with the same or similar clients, vendors, and industry standards. The fourth stage entails full cultural integration. To succeed, the lifted-out team members must be willing to re-earn credibility by proving their value and winning their new colleagues' trust. PMID:17183798

  16. Thermography of volcanic areas on Piton de la Fournaise, Reunion Island : Mapping surface properties and possible detection of convective air flow within volcanic debris

    NASA Astrophysics Data System (ADS)

    Antoine, R.; Baratoux, D.; Rabinowicz, M.; Saracco, G.; Bachelery, P.; Staudacher, T.; Fontaine, F.

    2007-12-01

    We report on the detection of air convection in a couple of quasi circular cavities forming the 300 years old volcanically inactive cone of Formica Leo (Piton de la Fournaise, Reunion Island) [1]. Infrared thermal images of the cone have been acquired in 2006 from a hand held camera at regular time interval during a complete diurnal cycle. During night and dawn, the data display hot rims and cold centers. Both the conductivity contrasts of the highly porous soils filling the cavities and their 30° slopes are unable to explain the systematic rim to center temperature drop. Accordingly, this signal could be attributed to an air convection dipping inside the highly porous material at the center of each cavity, then flowing upslope along the base of the soil layer, before exiting it along the rims. Anemometrical and electrical data acquired in 2007 allow for the first time the direct detection of this air flow on the field: dipping gas velocities are measured at the center of the cone and self-potentials anomalies [2] generated by the humid air flow in the porous medium are detected. To quantify this process, we present 2D/3D numerical models of air convection in a sloped volcanic soil with a surface temperature evolving between day and night and taking into account electrical phenomena created by the air flow. At this present stage, this work constitutes a first step to investigate the deep structure of the active caldera of Bory-Dolomieu. The detection of the air flow at the surface could be of paramount importance for the understanding of volcanic hazards of the Reunion volcano. [1] Antoine et. al, submitted to G-Cubed [2] Darnet, PhD, Université Louis Pasteur (2003)

  17. Rockets and People. Volume 1

    NASA Technical Reports Server (NTRS)

    Chertok, Boris E; Siddiqi, Asif A. (Editor)

    2005-01-01

    Much has been written in the West on the history of the Soviet space program but few Westerners have read direct first-hand accounts of the men and women who were behind the many Russian accomplishments in exploring space.The memoirs of Academician Boris Chertok, translated from the original Russian, fills that gap.Chertok began his career as an electrician in 1930 at an aviation factory near Moscow.Twenty-seven years later, he became deputy to the founding figure of the Soviet space program, the mysterious Chief Designer Sergey Korolev. Chertok s sixty-year-long career and the many successes and failures of the Soviet space program constitute the core of his memoirs, Rockets and People. These writings are spread over four volumes. This is volume I. Academician Chertok not only describes and remembers, but also elicits and extracts profound insights from an epic story about a society s quest to explore the cosmos. In Volume 1, Chertok describes his early years as an engineer and ends with the mission to Germany after the end of World War II when the Soviets captured Nazi missile technology and expertise. Volume 2 takes up the story with the development of the world s first intercontinental ballistic missile ICBM) and ends with the launch of Sputnik and the early Moon probes. In Volume 3, Chertok recollects the great successes of the Soviet space program in the 1960s including the launch of the world s first space voyager Yuriy Gagarin as well as many events connected with the Cold War. Finally, in Volume 4, Chertok meditates at length on the massive Soviet lunar project designed to beat the Americans to the Moon in the 1960s, ending with his remembrances of the Energiya-Buran project.

  18. Coronal extension of the MURaM radiative MHD code: From quiet sun to flare simulations

    NASA Astrophysics Data System (ADS)

    Rempel, Matthias D.; Cheung, Mark

    2016-05-01

    We present a new version of the MURaM radiative MHD code, which includes a treatment of the solar corona in terms of MHD, optically thin radiative loss and field-aligned heat conduction. In order to relax the severe time-step constraints imposed by large Alfven velocities and heat conduction we use a combination of semi-relativistic MHD with reduced speed of light ("Boris correction") and a hyperbolic formulation of heat conduction. We apply the numerical setup to 4 different setups including a mixed polarity quiet sun, an open flux region, an arcade solution and an active region setup and find all cases an amount of coronal heating sufficient to maintain a corona with temperatures from 1 MK (quiet sun) to 2 MK (active region, arcade). In all our setups the Poynting flux is self-consistently created by photospheric and sub-photospheric magneto-convection in the lower part of our simulation domain. Varying the maximum allowed Alfven velocity ("reduced speed of light") leads to only minor changes in the coronal structure as long as the limited Alfven velocity remains larger than the speed of sound and about 1.5-3 times larger than the peak advection velocity. We also found that varying details of the numerical diffusivities that govern the resistive and viscous energy dissipation do not strongly affect the overall coronal heating, but the ratio of resistive and viscous energy dependence is strongly dependent on the effective numerical magnetic Prandtl number. We use our active region setup in order to simulate a flare triggered by the emergence of a twisted flux rope into a pre-existing bipolar active region. Our simulation yields a series of flares, with the strongest one reaching GOES M1 class. The simulation reproduces many observed properties of eruptions such as flare ribbons, post flare loops and a sunquake.

  19. Functional diversity, succession, and human-mediated disturbances in raised bog vegetation.

    PubMed

    Dyderski, Marcin K; Czapiewska, Natalia; Zajdler, Mateusz; Tyborski, Jarosław; Jagodziński, Andrzej M

    2016-08-15

    Raised and transitional bogs are one of the most threatened types of ecosystem, due to high specialisation of biota, associated with adaptations to severe environmental conditions. The aim of the study was to characterize the relationships between functional diversity (reflecting ecosystem-shaping processes) of raised bog plant communities and successional gradients (expressed as tree dimensions) and to show how impacts of former clear cuts may alter these relationships in two raised bogs in 'Bory Tucholskie' National Park (N Poland). Herbaceous layers of the plant communities were examined by floristic relevés (25m(2)) on systematically established transects. We also assessed patterns of tree ring widths. There were no relationships between vegetation functional diversity components and successional progress: only functional dispersion was negatively, but weakly, correlated with median DBH. Lack of these relationships may be connected with lack of prevalence of habitat filtering and low level of competition over all the successional phases. Former clear cuts, indicated by peaks of tree ring width, influenced the growth of trees in the bogs studied. In the bog with more intensive clear cuts we found more species with higher trophic requirements, which may indicate nutrient influx. However, we did not observe differences in vegetation patterns, functional traits or functional diversity indices between the two bogs studied. We also did not find an influence of clear cut intensity on relationships between functional diversity indices and successional progress. Thus, we found that alteration of the ecosystems studied by neighbourhood clear cuts did not affect the bogs strongly, as the vegetation was resilient to these impacts. Knowledge of vegetation resilience after clear cuts may be crucial for conservation planning in raised bog ecosystems. PMID:27110977

  20. PREFACE Preface

    NASA Astrophysics Data System (ADS)

    Bleicher, Markus; Caines, Helen; Calderon de la Barca Sanchez, Manuel; de Falco, Alessandro; Fries, Rainer; Granier de Cassagnac, Raphael; Hippolyte, Boris; Mischke, Andre; Nardi, Marzia; Salgado, Carlos A.

    2011-01-01

    The 4th Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus-nucleus Collisions (Hot Quarks 2010) was held in La Londe-Les-Maures, France, from June 21-26, 2010. Following the traditions of the conference, this meeting gathered more than 70 participants in the first years of their scientific careers. The present issue contains the proceedings of this workshop. The articles published in this volume clearly show the presence of a dynamic new generation of physicists interested in the different aspects of high energy nuclear collisions. The newest results from RHIC at Brookhaven and SPS at CERN were presented, as well as the latest results from the proton-proton programme from the LHC at CERN, while waiting for the data of the lead-lead collisions only available some months after the meeting. Along with these experimental findings, the corresponding theoretical research was also extensively discussed as well as the new perspectives for future facilities like FAIR, EIC and LHeC. We wish to thank the sponsors of the Hot Quarks 2010 Conference, who supported the authors of this volume: IN2P3/CNRS (France), EMMI (Germany), Institut Pluridisciplinaire Hubert Curien (France), National Science Foundation (USA), CERN (Switzerland), Helmholtz International Center for FAIR (Germany), Xunta de Galicia (Spain) and the Journal of Physics G. Markus Bleicher (Frankfurt (HIC4FAIR), Germany)Helen Caines (Yale University, USA)Manuel Calderon de la Barca Sanchez (UC Davis, USA)Alessandro de Falco (Cagliari/INFN, Italy)Rainer Fries (Texas A & M University, USA) Raphael Granier de Cassagnac (Ecole Polytechnique, France)Boris Hippolyte (IPHC, Strasbourg, France)Andre Mischke (Utrecht University, The Netherlands)Marzia Nardi (Torino/INFN, Italy)Carlos A Salgado (Universidade de Santiago de Compostela, Galicia, Spain)

  1. Geodynamic evolution of Drake Passage in Post Miocene time, West Antarctica.

    NASA Astrophysics Data System (ADS)

    Teterin, Dmitry

    2010-05-01

    At present it is assumed that within continental margin of Drake Passage the process of transformation from active type of margin to passive one has been taking place since the spreading on ridge Aluk stopped 3.3 million years ago. In spite of strict geological-geophysical scrutiny of the region the nature of Bransfield Strait is not clear until now. Most explorers do not doubt in rifting nature of the strict, however the model of the formation of the rift is under discussion. Some theories assume that the sharp decrease of subduction velocity from 6.4 to 2.6 cm/year 7.8 million years ago and then the ending of subduction 3.3 million years ago caused the moving of heavy subduction lithosphere slab of the plate Phoenix towards the ocean and led to the formation of the rift zone. Alternative model states that the formation of the rift zone comes out of tectonic deformations propagation from the direction of the ridge Southern Scotia. New data on the structure of the relief, the sediment and the ocean crust were obtained during marine geological-geophysical expeditions of German RV Polarstern and Russian RV Academician Boris Petrov. This information allows one to understand some properties of the evolution of the continental margin of Drake Passage and the origin of Bransfield Strait. Joint analysis and interpretation of new data and available geological-geophysical information on the region show that the stop of spreading on the ridge Aluk 3.3 million years ago led to the redistribution of complex geometry of expansion and compression axes because of mutual drift of Antarctic, Scotia and Phoenix plates and was a trigger mechanism for the beginning of expansion deformations propagation from the direction of the ridge Southern Scotia and the formation of Bransfield Strait ridge.

  2. Natural Convection Heat Transfer in a Rectangular Liquid Metal Pool With Bottom Heating and Top Cooling

    SciTech Connect

    Lee, Il S.; Yu, Yong H.; Son, Hyoung M.; Hwang, Jin S.; Suh, Kune Y.

    2006-07-01

    An experimental study is performed to investigate the natural convection heat transfer characteristics with subcooled coolant to create engineering database for basic applications in a lead alloy cooled reactor. Tests are performed in the ALTOS (Applied Liquid-metal Thermal Operation Study) apparatus as part of MITHOS (Metal Integrated Thermo Hydrodynamic Operation System). A relationship is determined between the Nusselt number Nu and the Rayleigh number Ra in the liquid metal rectangular pool. Results are compared with correlations and experimental data in the literature. Given the similar Ra condition, the present test results for Nu of the liquid metal pool with top subcooling are found to be similar to those predicted by the existing correlations or experiments. The current test results are utilized to develop natural convection heat transfer correlations applicable to low Prandtl number Pr fluids that are heated from below and cooled by the external coolant above. Results from this study are slated to be used in designing BORIS (Battery Optimized Reactor Integral System), a small lead cooled modular fast reactor for deployment at remote sites cycled with MOBIS (Modular Optimized Brayton Integral System) for electricity generation, tied with NAVIS (Naval Application Vessel Integral System) for ship propulsion, joined with THAIS (Thermochemical Hydrogen Acquisition Integral System) for hydrogen production, and coupled with DORIS (Desalination Optimized Reactor Integral System) for seawater desalination. Tests are performed with Wood's metal (Pb-Bi-Sn-Cd) filling a rectangular pool whose lower surface is heated and upper surface cooled by forced convection of water. The test section is 20 cm long, 11.3 cm high and 15 cm wide. The simulant has a melting temperature of 78 deg. C. The constant temperature and heat flux condition was realized for the bottom heating once the steady state had been met. The test parameters include the heated bottom surface temperature

  3. Estimation of out-of-pocket costs of patients at the methadone maintenance therapy clinic in Malaysia.

    PubMed

    Manan, Mohamed Mansor; Ali, Salmiah Mohd; Khan, Muhammad Anwar Nawab; Jafarian, Sara

    2015-09-01

    Out-of-pocket (OOP) payments may burden Methadone Maintenance Clinic patients. Since treatment is fully subsidized by the government, financial constraint might lead to patients being made to pay or be given incentive for inconvenience of therapy. This study thus evaluates the characteristic and commitment of methadone therapy patient's in terms of OOP cost, Willingness-To-Pay (WTP) and Willingness-To-Accept (WTA) concept. This survey utilizes the questionnaire by Boris ova & Goodman (2003) on the OOP, WTP and WTA. The forty adult patient's selected medical records from year 2009-2011 were from an urban government methadone clinic. Subject's selection was by convenient sampling based on the predetermined criteria. Most were male (95%) and Malay (60%) was the predominant group. Patients were group into three income groups; ≤ RM1000, ≥ RM1000 -≤ RM2000 and ≥ RM3000. The average OOP cost per month was RM391.30 (s.d RM337.50), which is about 35% of employed patient's monthly income. The wide variation could be attributed by high inter-individual and significant differences between patients in terms of transport, times taken to clinic, cost per trip and weekly household income (p=<0.05). Patients with income of less than RM1000 showed the highest tendency to pay for treatment, asked for the least money for inconvenience and many are unwilling to accept any payments. These findings showed that WTP and WTA is less of a concern for patients in the low-income group. To conclude, OOP payment is not a treatment barrier for most of the urban MMT patients. PMID:26408891

  4. Density Predictions of Mercury's Exosphere Utilizing HEMO, the Hermean Exosphere Model of Oxygen, Including the Effects of Photodissociation

    NASA Astrophysics Data System (ADS)

    Grotheer, E.; Mangano, V.; Livi, S. A.

    2014-12-01

    The work presented here builds on the results of Grotheer & Livi [2014], which found that the majority of the vapor produced due to meteoroid impacts on Mercury is caused by meteoroids with masses 4.2 x 10-7 g ≤ m ≤ 8.3 x 10-2 g. Meteoroids with a mass of 2.1 x 10-4 g are the largest contributors to the vapor released by meteoroid impacts, thus here we focus on meteoroids with such masses as an input to a particle tracing simulation called the Hermean Exosphere Model of Oxygen (HEMO). The HEMO simulations include 36 different particle species which can be released via meteoritic impact vaporization, based on the abundances determined by Berezhnoy & Klumov [2008]. After the initial simulation of the meteoroid impact, the released particles are affected by the gravitational pull of the planet Mercury, as well as the Sun's radiation. Particles may be photoionized or in the case of molecules also photodissociated. Due to the effects of photodissociation, a total of 38 species are actually present in the simulation, since 2 species are not directly released by impact vaporization but may be created due to photodissociation. These simulations record various pieces of information about each simulated particle, including position and velocity, for each time-step of the model. This information is then utilized to construct density profiles for each simulation run, as well as for aggregates of simulation runs with similar input parameters. The results are intended to aid the interpretation of results from the MESSENGER and BepiColombo missions to Mercury, with a particular focus on atomic and molecular oxygen. ReferencesAlexey A. Berezhnoy and Boris A. Klumov. Impacts as sources of the exosphere on Mercury. Icarus, 195(2): 511-522, 2008. Emmanuel B. Grotheer and Stefano A. Livi. Small meteoroids' major contribution to Mercury's exosphere. Icarus, 227(1): 1-7, 2014.

  5. Quantitative comparisons of numerical models of brittle deformation

    NASA Astrophysics Data System (ADS)

    Buiter, S.

    2009-04-01

    Numerical modelling of brittle deformation in the uppermost crust can be challenging owing to the requirement of an accurate pressure calculation, the ability to achieve post-yield deformation and localisation, and the choice of rheology (plasticity law). One way to approach these issues is to conduct model comparisons that can evaluate the effects of different implementations of brittle behaviour in crustal deformation models. We present a comparison of three brittle shortening experiments for fourteen different numerical codes, which use finite element, finite difference, boundary element and distinct element techniques. Our aim is to constrain and quantify the variability among models in order to improve our understanding of causes leading to differences between model results. Our first experiment of translation of a stable sand-like wedge serves as a reference that allows for testing against analytical solutions (e.g., taper angle, root-mean-square velocity and gravitational rate of work). The next two experiments investigate an unstable wedge in a sandbox-like setup which deforms by inward translation of a mobile wall. All models accommodate shortening by in-sequence formation of forward shear zones. We analyse the location, dip angle and spacing of thrusts in detail as previous comparisons have shown that these can be highly variable in numerical and analogue models of crustal shortening and extension. We find that an accurate implementation of boundary friction is important for our models. Our results are encouraging in the overall agreement in their dynamic evolution, but show at the same time the effort that is needed to understand shear zone evolution. GeoMod2008 Team: Markus Albertz, Michele Cooke, Susan Ellis, Taras Gerya, Luke Hodkinson, Kristin Hughes, Katrin Huhn, Boris Kaus, Walter Landry, Bertrand Maillot, Christophe Pascal, Anton Popov, Guido Schreurs, Christopher Beaumont, Tony Crook, Mario Del Castello and Yves Leroy

  6. Quantitative comparisons of numerical models of brittle wedge dynamics

    NASA Astrophysics Data System (ADS)

    Buiter, Susanne

    2010-05-01

    Numerical and laboratory models are often used to investigate the evolution of deformation processes at various scales in crust and lithosphere. In both approaches, the freedom in choice of simulation method, materials and their properties, and deformation laws could affect model outcomes. To assess the role of modelling method and to quantify the variability among models, we have performed a comparison of laboratory and numerical experiments. Here, we present results of 11 numerical codes, which use finite element, finite difference and distinct element techniques. We present three experiments that describe shortening of a sand-like, brittle wedge. The material properties of the numerical ‘sand', the model set-up and the boundary conditions are strictly prescribed and follow the analogue setup as closely as possible. Our first experiment translates a non-accreting wedge with a stable surface slope of 20 degrees. In agreement with critical wedge theory, all models maintain the same surface slope and do not deform. This experiment serves as a reference that allows for testing against analytical solutions for taper angle, root-mean-square velocity and gravitational rate of work. The next two experiments investigate an unstable wedge in a sandbox-like setup, which deforms by inward translation of a mobile wall. The models accommodate shortening by formation of forward and backward shear zones. We compare surface slope, rate of dissipation of energy, root-mean-square velocity, and the location, dip angle and spacing of shear zones. We show that we successfully simulate sandbox-style brittle behaviour using different numerical modelling techniques and that we obtain the same styles of deformation behaviour in numerical and laboratory experiments at similar levels of variability. The GeoMod2008 Numerical Team: Markus Albertz, Michelle Cooke, Tony Crook, David Egholm, Susan Ellis, Taras Gerya, Luke Hodkinson, Boris Kaus, Walter Landry, Bertrand Maillot, Yury Mishin

  7. Physics of Traffic Flow

    NASA Astrophysics Data System (ADS)

    Davis, L. C.

    2015-03-01

    The Texas A&M Transportation Institute estimated that traffic congestion cost the United States 121 billion in 2011 (the latest data available). The cost is due to wasted time and fuel. In addition to accidents and road construction, factors contributing to congestion include large demand, instability of high-density free flow and selfish behavior of drivers, which produces self-organized traffic bottlenecks. Extensive data collected on instrumented highways in various countries have led to a better understanding of traffic dynamics. From these measurements, Boris Kerner and colleagues developed a new theory called three-phase theory. They identified three major phases of flow observed in the data: free flow, synchronous flow and wide moving jams. The intermediate phase is called synchronous because vehicles in different lanes tend to have similar velocities. This congested phase, characterized by lower velocities yet modestly high throughput, frequently occurs near on-ramps and lane reductions. At present there are only two widely used methods of congestion mitigation: ramp metering and the display of current travel-time information to drivers. To find more effective methods to reduce congestion, researchers perform large-scale simulations using models based on the new theories. An algorithm has been proposed to realize Wardrop equilibria with real-time route information. Such equilibria have equal travel time on alternative routes between a given origin and destination. An active area of current research is the dynamics of connected vehicles, which communicate wirelessly with other vehicles and the surrounding infrastructure. These systems show great promise for improving traffic flow and safety.

  8. List of participants at SIDE IV meeting, Tokyo, 27 November--1 December 2000

    NASA Astrophysics Data System (ADS)

    2001-12-01

    Mark J Ablowitz, Vsevolod Adler, Mark Alber, Said Belmehdi, Marco Boiti, Claude Brezinski, R Bullough, Y M Chiang, Theodore Chihara, Peter A Clarkson, Robert Conte, Adam Doliwa, Vladimir Dorodnitsyn, Mitsuaki Eguchi, Claire Gilson, Basil Grammaticos, Valeri Gromak, Rod Halburd, Koji Hasegawa, Jarmo Hietarinta, Ryogo Hirota, Xing Biao Hu, M Idzumi, J Inoguchi, Hiroya Ishikara, Mourad Ismail, Shin Isojima, Kenichi Ito, Yoshiaki Itoh, Masashi Iwasaki, Klara Janglajew, Michio Jimbo, Nalini Joshi, Kenji Kajiwara, Saburo Kakei, Masaru Kamata, Satoshi Kamei, Rinat Kashaev, Shingo Kawai, Taeko Kimijima, K Kimura, Anatol Kirillov, Koichi Kondo, Boris Konopelchenko, Martin Kruskal, Atsuo Kuniba, Wataru Kunishima, Franklin Lambert, Serguei Leble, Decio Levi, Shigeru Maeda, Manuel Manas, Ken-Ichi Maruno, Tetsu Masuda, J Matsukidaira, Atsushi Matsumiya, Shigeki Matsutani, Yukitaka Minesaki, Mikio Murata, Micheline Musette, Atsushi Nagai, Katsuya Nakagawa, Atsushi Nakamula, Akira Nakamura, Yoshimasa Nakamura, Frank Nijhoff, J J C Nimmo, Katsuhiro Nishinari, Michitomo Nishizawa, A Nobe, Masatoshi Noumi, Yaeko Ohsaki, Yasuhiro Ohta, Kazuo Okamoto, Alexandre Orlov, Naoki Osada, Flora Pempinelli, Spiro Pyrlis, Reinout Quispel, Orlando Ragnisco, Alfred Ramani, Jean-Pierre Ramis, Andreas Ruffing, Simon Ruijsenaars, Satoru Saito, Noriko Saitoh, Hidetaka Sakai, Paulo Santini, Narimasa Sasa, Ryu Sasaki, Yoshikatsu Sasaki, Junkichi Satsuma, Sergei Sergeev, Nobuhiko Shinzawa, Evgueni Sklyanin, Juris Suris, Norio Suzuki, Yukiko Tagami, Katsuaki Takahashi, Daisuke Takahashi, Tomoyuki Takenawa, Yoshiro Takeyama, K M Tamizhmani, T Tamizhmani, Kouichi Toda, Morikatsu Toda, Tetsuji Tokihiro, Takayuki Tsuchida, Yohei Tsuchiya, Teruhisa Tsuda, Satoru Tsujimoto, Walter Van Assche, Claude Viallet, Luc Vinet, Shinsuke Watanabe, Yoshihida Watanabe, Ralph Willox, Pavel Winternitz, Yasuhiko Yamada, Yuji Yamada, Jin Yoneda, Haruo Yoshida, Katsuhiko Yoshida, Daisuke Yoshihara, Fumitaka Yura, J

  9. Molecular attraction of condensed bodies

    NASA Astrophysics Data System (ADS)

    Derjaguin, B. V.; Abrikosova, I. I.; Lifshitz, E. M.

    2015-09-01

    From the Editorial Board. As a contribution to commemorating the 100th anniversary of the birth of Evgenii Mikhailovich Lifshitz, it was found appropriate by the Editorial Board of Uspekhi Fizicheskikh Nauk (UFN) [Physics-Uspekhi] journal that the materials of the jubilee-associated Scientific Session of the Physical Sciences Division of the Russian Academy of Sciences published in this issue (pp. 877-905) be augmented by the review paper "Molecular attraction of condensed bodies" reproduced from a 1958 UFN issue. Included in this review, in addition to an account by Evgenii Mikhailovich Lifshitz of his theory of molecular attractive forces between condensed bodies (first published in Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki (ZhETF) in 1955 and in its English translation Journal of Experimental and Theoretical Physics (JETP) in 1956), is a summary of a series of experimental studies beginning in 1949 by Irina Igorevna Abrikosova at the Institute of Physical Chemistry of the Academy of Sciences of the USSR in a laboratory led by Boris Vladimirovich Derjaguin (1902-1994), a Corresponding Member of the USSR Academy of Sciences. In 1958, however, UFN was not yet available in English translation, so the material of the review is insufficiently accessible to the present-day English-speaking reader. This is the reason why the UFN Editorial Board decided to contribute to celebrating the 100th anniversary of E M Lifshitz's birthday by reproducing on the journal's pages a 1958 review paper which contains both E M Lifshitz's theory itself and the experimental data that underpinned it (for an account of how Evgenii Mikhailovich Lifshitz was enlisted to explain the experimental results of I I Abrikosova and B V Derjaguin, see the letter to the editors N P Danilova on page 925 of this jubilee collection of publications).

  10. Numerical simulation of equatorial plasma bubbles over Cachimbo: COPEX campaign

    NASA Astrophysics Data System (ADS)

    Carrasco, A. J.; Batista, I. S.; Abdu, M. A.

    2014-08-01

    The problem of day-to-day variability in onset of equatorial spread F (ESF) is addressed using data from the 2002 COPEX observational campaign in Brazil and numerical modeling. The observational results show that for values of virtual height of the F layer base less than 355 km at around 18:35 LT, and for the prereversal peak enhancement of the vertical plasma drift (Vp) less than 30 m/s, the spread-F (ESF) was absent on four nights over Cachimbo (9.5°S, 54.8°W, dip latitude = -2.1°). In this work we analyze the geophysical conditions for the generation of the irregularities by comparing the nights with and without the ESF. In the comparison a numerical code is used to simulate plasma irregularity development in an extended altitude range from the bottom of the equatorial F layer. The code uses the flux corrected transport method with Boris-Book’s flux limiter for the spatial integration and a predictor-corrector method for the direct time integration of the continuity equation for O+ and the SOR (Successive-Over-Relaxation) method for electric potential equation. The code is tested with different evening eastward electric fields (or vertical drifts Vp < 30 m/s and Vp > 30 m/s) in order to study the influence of the prereversal enhancement in the zonal electric field on plasma bubble formation and development. The code also takes into account the zonal wind, the vertical electric field and the collision frequency of ions with neutrals and the amplitude of initial perturbation. The simulation shows a good agreement with the observational results of the ESF. The results of the code suggest that the instability can grow at the F layer bottomside by the Rayleigh-Taylor mechanism only when the Vp > 30 m/s. In the analyzed cases we have considered the competition of other geophysical parameters in the generation of plasma structures.

  11. Cataclysmic variables to be monitored for HST observations

    NASA Astrophysics Data System (ADS)

    Waagen, Elizabeth O.

    2012-09-01

    Drs. Boris Gaensicke (Warwick University), Joseph Patterson (Columbia University, Center for Backyard Astrophysics), and Arne Henden (AAVSO), on behalf of a consortium of 16 astronomers, requested the help of AAVSO observers in monitoring the ~40 cataclysmic variables in support of Hubble Space Telescope observations in the coming months. The HST COS (Cosmic Origins Spectrograph) will be carrying out far-ultraviolet spectroscopy of ~40 CVs sequentially, with the aim to measure the temperatures, atmospheric compositions, rotation rates, and eventually masses of their white dwarfs. The primary purpose of the monitoring is to know whether each target is in quiescence immediately prior to the observation window; if it is in outburst it will be too bright for the HST instrumentation. Based on the information supplied by the AAVSO, the HST scheduling team will make the decision (usually) the evening before the scheduled observing time as to whether to go forward with the HST observations. For CCD observers, simultaneous photometry [shortly before, during, and after the HST observations] would be ideal. B filter would be best for a light curve, although for the magnitude estimates, V would be best. Finder charts may be created using the AAVSO Variable Star Plotter (http://www.aavso.org/vsp). Observations should be submitted to the AAVSO International Database. If the target is seen in outburst, please contact the AAVSO immediately and post a message to the Observations and Campaigns & Observations Reports forum (http://www.aavso.org/forum). This campaign will run the better part of a year or longer. See full Alert Notice for more details and list of objects.

  12. BOREAS Level-0 C-130 Aerial Photography

    NASA Technical Reports Server (NTRS)

    Newcomer, Jeffrey A.; Dominguez, Roseanne; Hall, Forrest G. (Editor)

    2000-01-01

    For BOReal Ecosystem-Atmosphere Study (BOREAS), C-130 and other aerial photography was collected to provide finely detailed and spatially extensive documentation of the condition of the primary study sites. The NASA C-130 Earth Resources aircraft can accommodate two mapping cameras during flight, each of which can be fitted with 6- or 12-inch focal-length lenses and black-and-white, natural-color, or color-IR film, depending upon requirements. Both cameras were often in operation simultaneously, although sometimes only the lower resolution camera was deployed. When both cameras were in operation, the higher resolution camera was often used in a more limited fashion. The acquired photography covers the period of April to September 1994. The aerial photography was delivered as rolls of large format (9 x 9 inch) color transparency prints, with imagery from multiple missions (hundreds of prints) often contained within a single roll. A total of 1533 frames were collected from the C-130 platform for BOREAS in 1994. Note that the level-0 C-130 transparencies are not contained on the BOREAS CD-ROM set. An inventory file is supplied on the CD-ROM to inform users of all the data that were collected. Some photographic prints were made from the transparencies. In addition, BORIS staff digitized a subset of the tranparencies and stored the images in JPEG format. The CD-ROM set contains a small subset of the collected aerial photography that were the digitally scanned and stored as JPEG files for most tower and auxiliary sites in the NSA and SSA. See Section 15 for information about how to acquire additional imagery.

  13. An isolated tornadic supercell of 14 July 2012 in Poland - A prediction technique within the use of coarse-grid WRF simulation

    NASA Astrophysics Data System (ADS)

    Taszarek, Mateusz; Czernecki, Bartosz; Walczakiewicz, Szymon; Mazur, Andrzej; Kolendowicz, Leszek

    2016-09-01

    On 14 July 2012 a shortwave trough with a cold front passed through Poland. A few tornadoes were reported in the north central part of the country within an isolated cyclic supercell. The cell moved along the thermal and moisture horizontal gradients and the support of a synoptic scale lift. An analysis allowed for setting up four tornado damage tracks in a distance of 100 km and with a total length of 60 km. Tornadoes damaged 105 buildings with predominant intensity of F1-F2/T3-T4 (maximum F3/T6) in Fujita/TORRO scale, caused 1 fatality, 10 injures and felled 500 hectares of Bory Tucholskie forest. The main aim of this article was to analyze this event and assess the possibilities of its short-term prediction. In order to achieve this, a model forecast data derived from WRF-ARW simulation with a spatial resolution of 15 km and initial conditions extracted from 0000 UTC GFS was used. An analysis yielded that the cell moved in the environment of a low lifting condensation level, rich boundary layer's moisture content and a steepening vertical lapse rates that provided the presence of a thermodynamic instability. A wind vectors tilting with height and an increased vertical wind shear occurred as well. A forecasting method that combined a Universal Tornadic Index composite parameter with a convective precipitation filter showed that convective cells at 1500 UTC in the north central Poland had a potential to become tornadic. Within the use of a proposed methodology, it was possible to issue a tornado forecast for the areas where an index pointed the risk.

  14. UV effects on photosynthesis and DNA in propagules of three Antarctic seaweeds (Adenocystis utricularis, Monostroma hariotii and Porphyra endiviifolium).

    PubMed

    Zacher, Katharina; Roleda, Michael Y; Hanelt, Dieter; Wiencke, Christian

    2007-05-01

    Ozone depletion is highest during spring and summer in Antarctica, coinciding with the seasonal reproduction of most macroalgae. Propagules are the life-stage of an alga most susceptible to environmental perturbations therefore, reproductive cells of three intertidal macroalgal species Adenocystis utricularis (Bory) Skottsberg, Monostroma hariotii Gain, and Porphyra endiviifolium (A and E Gepp) Chamberlain were exposed to photosynthetically active radiation (PAR), PAR + UV-A and PAR + UV-A + UV-B radiation in the laboratory. During 1, 2, 4, and 8 h of exposure and after 48 h of recovery, photosynthetic efficiency, and DNA damage were determined. Saturation irradiance of freshly released propagules varied between 33 and 83 mumol photons m(-2) s(-1) with lowest values in P. endiviifolium and highest values in M. hariotii. Exposure to 22 mumol photons m(-2) s(-1 )PAR significantly reduced photosynthetic efficiency in P. endiviifolium and M. hariotii, but not in A. utricularis. UV radiation (UVR) further decreased the photosynthetic efficiency in all species but all propagules recovered completely after 48 h. DNA damage was minimal or not existing. Repeated exposure of A. utricularis spores to 4 h of UVR daily did not show any acclimation of photosynthesis to UVR but fully recovered after 20 h. UVR effects on photosynthesis are shown to be species-specific. Among the tested species, A. utricularis propagules were the most light adapted. Propagules obviously possess good repair and protective mechanisms. Our study indicates that the applied UV dose has no long-lasting negative effects on the propagules, a precondition for the ecological success of macroalgal species in the intertidal. PMID:17171375

  15. High prevalence of toxic shock syndrome toxin-producing epidemic methicillin-resistant Staphylococcus aureus 15 (EMRSA-15) strains in Kuwait hospitals.

    PubMed

    Udo, E E; Boswihi, S S; Al-Sweih, N

    2016-07-01

    This study characterized EMRSA-15 isolates obtained from patients in Kuwait hospitals for their genotypic relatedness, antibiotic resistance and carriage of virulence genes using pulsed-field gel electrophoresis (PFGE), coagulase serotyping, SCCmec subtyping, spa typing, multilocus sequence typing and DNA microarray. The isolates were resistant to trimethoprim (75.6%), ciprofloxacin (29.7%), erythromycin and clindamycin (24.3%), tetracycline (19.0%), and gentamicin and kanamycin (21.6%). All 37 isolates belonged to sequence type (ST) 22, coagulase type XI, three PFGE types and eight subtypes, ten spa types including t223 (51.3%), t852 (13.5%), t032 (8.1%), t790 (8.1%), t3107 (5.4%) and one each of t309, t2251, t3935, t5708 and t5983. Twenty-six isolates (70.2%) carried SCCmec IVa, eight isolates carried SCCmec IV and three isolates carried SCCmec IVh. All isolates carried agr1, cap5 and egc gene cluster (seg, sei, selm, seln, selo, and selu). tst (toxic shock syndrome toxin) was detected in 23 isolates. Eight isolates (21.6%) were positive for Panton-Valentine leukocidin (PVL). Genotypic analysis revealed that 62.1% of the isolates comprising ST22-IVa-t223 (51.3%) and ST22-IVa-t309/t2251/t3935/t5708 (10.8%) were CC22-[tst1(+)] UK EMRSA-15/Middle Eastern variant, 21.6% were CC22-PVL(+) EMRSA-15 variant and 16.2% were CC22-UK EMRSA-15/Barnim clone. These results show that the tst1 positive-ST22-IVa-t223 (Middle Eastern variant) and the CC22-PVL(+) EMRSA-15 variant were the dominant EMRSA-15 variants in Kuwait hospitals. PMID:27222714

  16. Epidemiological typing of meticillin-resistant Staphylococcus aureus isolates from Pakistan and India.

    PubMed

    Shabir, Sahida; Hardy, Katherine J; Abbasi, Waseem S; McMurray, Claire L; Malik, Salman A; Wattal, Chand; Hawkey, Peter M

    2010-03-01

    The levels of meticillin-resistant Staphylococcus aureus (MRSA) in Pakistan and India are known to be high, but few studies have described the epidemiology of the different MRSA clones present. In order to gain an understanding of the epidemiology of MRSA within this region, 60 MRSA isolates from Pakistan (49) and India (11) were genotyped. All isolates were typed using PFGE, staphylococcal interspersed repeat units (SIRUs), a restriction-modification method and staphylococcal cassette chromosome mec (SCCmec) typing. A subset of isolates that were distinct by PFGE and SIRUs were typed using multilocus sequence typing (MLST). Clonal complex (CC) 8 was the dominant clonal complex (57/60) and was present in both Pakistan and India. Within CC8, there were 10 SIRU profiles and 24 PFGE profiles. Two SIRU profiles were present in isolates from both India and Pakistan, whilst seven were distinct for Pakistan and one for India. All PFGE profiles were distinct for each of the two countries. Thirty-four of the 57 isolates carried SCCmec type III/IIIa and the remainder carried type IV SCCmec. MLST analysis of 14 CC8 isolates with diverse SIRU and PFGE profiles showed that all were single-locus variants, with nine belonging to sequence type (ST) 239, three to ST8 and two to ST113. From a single hospital in Pakistan, three isolates belonged to CC30 and all were indistinguishable by PFGE and SIRUs and carried the Panton-Valentine leukocidin gene. Thus, epidemiological typing of strains from three distinct locations in India and Pakistan revealed the predominance of one clonal complex and highly related STs. The ability of SIRUs and PFGE to differentiate within ST239 demonstrates their utility in defining local epidemiology in these countries. PMID:19926728

  17. Molecular epidemiology of Methicillin-resistant Staphylococcus aureus in Africa: a systematic review

    PubMed Central

    Abdulgader, Shima M.; Shittu, Adebayo O.; Nicol, Mark P.; Kaba, Mamadou

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) infections are a serious global problem, with considerable impact on patients and substantial health care costs. This systematic review provides an overview on the clonal diversity of MRSA, as well as the prevalence of Panton-Valentine leukocidin (PVL)-positive MRSA in Africa. A search on the molecular characterization of MRSA in Africa was conducted by two authors using predefined terms. We screened for articles published in English and French through to October 2014 from five electronic databases. A total of 57 eligible studies were identified. Thirty-four reports from 15 countries provided adequate genotyping data. CC5 is the predominant clonal complex in the healthcare setting in Africa. The hospital-associated MRSA ST239/ST241-III [3A] was identified in nine African countries. This clone was also described with SCCmec type IV [2B] in Algeria and Nigeria, and type V [5C] in Niger. In Africa, the European ST80-IV [2B] clone was limited to Algeria, Egypt and Tunisia. The clonal types ST22-IV [2B], ST36-II [2A], and ST612-IV [2B] were only reported in South Africa. No clear distinctions were observed between MRSA responsible for hospital and community infections. The community clones ST8-IV [2B] and ST88-IV [2B] were reported both in the hospital and community settings in Angola, Cameroon, Gabon, Ghana, Madagascar, Nigeria, and São Tomé and Príncipe. The proportion of PVL-positive MRSA carriage and/or infections ranged from 0.3 to 100% in humans. A number of pandemic clones were identified in Africa. Moreover, some MRSA clones are limited to specific countries or regions. We strongly advocate for more surveillance studies on MRSA in Africa. PMID:25983721

  18. Pediatric Staphylococcus aureus Isolate Genotypes and Infections from the Dawn of the Community-Associated Methicillin-Resistant S. aureus Epidemic Era in Chicago, 1994 to 1997

    PubMed Central

    Acree, Mary Ellen; Sieth, Julia J.; Boxrud, Dave J.; Dobbins, Ginette; Lynfield, Ruth; Boyle-Vavra, Susan; Daum, Robert S.

    2015-01-01

    Widespread infections with community-associated (CA) methicillin-resistant Staphylococcus aureus (MRSA) have occurred in the United States with the dissemination of the USA300 strain beginning in 2000. We examined 105 isolates obtained from children treated at the University of Chicago from 1994 to 1997 (75 methicillin-susceptible S. aureus [MSSA] and 30 MRSA isolates) in order to investigate for possible evidence of USA300 during this period. Infections were defined epidemiologically based on medical record review. The isolates underwent multilocus sequence typing (MLST), as well as assays for the Panton-Valentine leukocidin (PVL) genes, the protein A gene (spa), and arcA and opp3, proxy markers for the arginine catabolic mobile element (ACME), characteristic of USA300 MRSA. MRSA isolates also underwent staphylococcal cassette chromosome mec (SCCmec) typing and pulsed-field gel electrophoresis (PFGE) subtyping. MSSA isolates belonged to 17 sequence type (ST) groups. The 12 epidemiologically defined CA-MRSA infection isolates were either ST1 (n = 4) or ST8 (n = 8). They belonged to 3 different PFGE types: USA100 (n = 1), USA400 (n = 5), and USA500 (n = 6). Among the CA-MRSA infection isolates, 8 (67%) were PVL+. None of the MRSA or MSSA isolates contained arcA or opp3. Only one MRSA isolate was USA300 by PFGE. This was a health care-associated (HA) MRSA isolate, negative for PVL, that carried SCCmec type II. USA300 with its characteristic features was not identified in the collection from the years 1994 to 1997. PMID:26019202

  19. Epidemiology of emerging methicillin-resistant Staphylococcus aureus (MRSA) in Denmark: a nationwide study in a country with low prevalence of MRSA infection.

    PubMed

    Faria, Nuno A; Oliveira, Duarte C; Westh, Henrik; Monnet, Dominique L; Larsen, Anders R; Skov, Robert; de Lencastre, Hermínia

    2005-04-01

    Strict infection control measures introduced during the 1970s have kept the incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections extremely low in Denmark. Nevertheless, similarly to other countries, MRSA infections began to appear in the community in the late 1990s. A nationwide surveillance program has collected and stored all MRSA isolates since 1988 and, since 1999, clinical information has been also recorded. We used this information and isolates in a detailed epidemiological and molecular analysis of the 81 MRSA infections identified in Denmark in 2001. MRSA isolates were characterized by pulsed-field gel electrophoresis (PFGE), spa typing, multilocus sequence typing, and SCCmec typing. Comparison of the 45 community-onset MRSA (CO-MRSA) infections with the 36 hospital-acquired MRSA (HA-MRSA) infections showed several striking contrasts. Most CO-MRSA were recovered from skin and soft tissue infections caused by isolates carrying the Panton-Valentine leucocidin toxin genes, and the majority (84%) of isolates belonged to a single clonal type, ST80-IV, which has been found in the community in other European countries. Clone ST80-IV could be traced in Denmark back to 1993. ST80-IV was rarely found in HA-MRSA infections, which belonged to a large number of clonal types, including some pandemic MRSA clones. The low number of HA-MRSA infections and the diversity of MRSA clones in Danish hospitals may be the result of successful infection control measures that prevent spread of clones in hospitals. The mechanism of spread of the ST80-IV clone in the Danish community is not known, and new control measures are needed to control further spread of this and other CA-MRSA clones. PMID:15815005

  20. Adaptive change inferred from genomic population analysis of the ST93 epidemic clone of community-associated methicillin-resistant Staphylococcus aureus.

    PubMed

    Stinear, Timothy P; Holt, Kathryn E; Chua, Kyra; Stepnell, Justin; Tuck, Kellie L; Coombs, Geoffrey; Harrison, Paul Francis; Seemann, Torsten; Howden, Benjamin P

    2014-02-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has emerged as a major public health problem around the world. In Australia, ST93-IV[2B] is the dominant CA-MRSA clone and displays significantly greater virulence than other S. aureus. Here, we have examined the evolution of ST93 via genomic analysis of 12 MSSA and 44 MRSA ST93 isolates, collected from around Australia over a 17-year period. Comparative analysis revealed a core genome of 2.6 Mb, sharing greater than 99.7% nucleotide identity. The accessory genome was 0.45 Mb and comprised additional mobile DNA elements, harboring resistance to erythromycin, trimethoprim, and tetracycline. Phylogenetic inference revealed a molecular clock and suggested that a single clone of methicillin susceptible, Panton-Valentine leukocidin (PVL) positive, ST93 S. aureus likely spread from North Western Australia in the early 1970s, acquiring methicillin resistance at least twice in the mid 1990s. We also explored associations between genotype and important MRSA phenotypes including oxacillin MIC and production of exotoxins (α-hemolysin [Hla], δ-hemolysin [Hld], PSMα3, and PVL). High-level expression of Hla is a signature feature of ST93 and reduced expression in eight isolates was readily explained by mutations in the agr locus. However, subtle but significant decreases in Hld were also noted over time that coincided with decreasing oxacillin resistance and were independent of agr mutations. The evolution of ST93 S. aureus is thus associated with a reduction in both exotoxin expression and oxacillin MIC, suggesting MRSA ST93 isolates are under pressure for adaptive change. PMID:24482534

  1. Adaptive Change Inferred from Genomic Population Analysis of the ST93 Epidemic Clone of Community-Associated Methicillin-Resistant Staphylococcus aureus

    PubMed Central

    Stinear, Timothy P.; Holt, Kathryn E.; Chua, Kyra; Stepnell, Justin; Tuck, Kellie L.; Coombs, Geoffrey; Harrison, Paul Francis; Seemann, Torsten; Howden, Benjamin P.

    2014-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has emerged as a major public health problem around the world. In Australia, ST93-IV[2B] is the dominant CA-MRSA clone and displays significantly greater virulence than other S. aureus. Here, we have examined the evolution of ST93 via genomic analysis of 12 MSSA and 44 MRSA ST93 isolates, collected from around Australia over a 17-year period. Comparative analysis revealed a core genome of 2.6 Mb, sharing greater than 99.7% nucleotide identity. The accessory genome was 0.45 Mb and comprised additional mobile DNA elements, harboring resistance to erythromycin, trimethoprim, and tetracycline. Phylogenetic inference revealed a molecular clock and suggested that a single clone of methicillin susceptible, Panton-Valentine leukocidin (PVL) positive, ST93 S. aureus likely spread from North Western Australia in the early 1970s, acquiring methicillin resistance at least twice in the mid 1990s. We also explored associations between genotype and important MRSA phenotypes including oxacillin MIC and production of exotoxins (α-hemolysin [Hla], δ-hemolysin [Hld], PSMα3, and PVL). High-level expression of Hla is a signature feature of ST93 and reduced expression in eight isolates was readily explained by mutations in the agr locus. However, subtle but significant decreases in Hld were also noted over time that coincided with decreasing oxacillin resistance and were independent of agr mutations. The evolution of ST93 S. aureus is thus associated with a reduction in both exotoxin expression and oxacillin MIC, suggesting MRSA ST93 isolates are under pressure for adaptive change. PMID:24482534

  2. Prevalence and Molecular Characterization of Methicillin-Resistant Staphylococcus aureus ST398 Resistant to Tetracycline at a Spanish Hospital over 12 Years

    PubMed Central

    Camoez, Mariana; Sierra, Josep M.; Pujol, Miquel; Hornero, Ana; Martin, Rogélio; Domínguez, M. Angeles

    2013-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) ST398, associated with livestock animals, was described in 2003 as a new lineage infecting or colonizing humans. We evaluated the prevalence and molecular characteristics of MRSA ST398 isolated in the Hospital Universitari de Bellvitge from January 2000 to June 2011. Tetracycline resistant (Tet-R) MRSA isolates from single patients (pts) were screened by SmaI-pulsed field gel electrophoresis (PFGE). Nontypable MRSA strains by SmaI (NTSmaI)-MRSA were further analysed by ApaI-PFGE, spa, SCCmec, agr, MLST typing, and by DNA microarray hybridization. Among 164 pts harboring Tet-R MRSA, NTSmaI-MRSA ST398-agrI was found in 33 pts (20%). Although the first pt was detected in 2003, 22/33 pts (67%) were registered in the 2010–2011 period. Ten pts (30%) were infected and cancer was the most frequent underlying disease. In one case, death was due to MRSA-ST398-related infection. Five pulsotypes (A–E) were detected using ApaI-PFGE, with type A accounting for 76% of the strains. The majority of the studied isolates presented spa type t011 (70%) and SCCmec type V (88%). One strain was spa negative both by PCR and microarray analysis. Forty-nine percent of the studied isolates showed resistance to 3 or more antibiotic classes, in addition to beta-lactams. Ciprofloxacin resistance was 67%. Tet-R was mediated by tet(M) and tet(K) in 26 isolates. All isolates lacked Panton-Valentine Leukocidin production, as well as other significant toxins. This study displays the molecular features of MRSA-ST398 clone and shows the increase in tetracycline resistance together with arise in MRSA-ST398 isolates infecting or colonizing patients in our clinical setting. PMID:24039806

  3. Dissemination of Methicillin-Resistant Staphylococcus aureus (MRSA), USA300 Sequence Type 8 Lineage in Latin-America

    PubMed Central

    Reyes, Jinnethe; Rincón, Sandra; Díaz, Lorena; Panesso, Diana; Contreras, Germán A.; Zurita, Jeannete; Carrillo, Carlos; Rizzi, Adele; Guzmán, Manuel; Adachi, Javier; Chowdhury, Shahreen; Murray, Barbara E.; Arias, Cesar A.

    2009-01-01

    Background Methicillin-resistant Staphylococus aureus (MRSA) is an important nosocomial and community-associated (CA) pathogen. Recently, a variant of the MRSA USA300 clone emerged and disseminated in South-America causing important clinical problems. Methods S. aureus isolates were prospectively collected (2006 to 2008) from 32 tertiary hospitals in Colombia, Ecuador, Peru, and Venezuela. MRSA isolates were subjected to antimicrobial susceptibility testing, pulsed field gel electrophoresis (PFGE), and categorized as healthcare-associated (HA)-like or CA-like clones based on genotypic characteristics and detection of genes encoding the Panton-Valentine leukocidin (PVL) and staphylococcal cassette mec (SCCmec) IV. Additionally, MLST of representative isolates of each major CA-MRSA pulsotype, and detection of USA300-associated toxins and the arcA gene were performed in all isolates categorized as CA-MRSA. Results A total of 1570 S. aureus were included; 651 were MRSA (41%), with the highest rates of MRSA isolation in Peru (62%), and lowest in Venezuela (26%) and 71%, 27%, and 2% were classified as HA-like, CA-like, and non-CA/HA-like clones, respectively. Only 9 MRSA isolates were confirmed to have reduced susceptibility to glycopeptides (GISA phenotype). The most common pulsotype (designated ComA) amongst the CA-like MRSA strains was found in 96% of isolates with the majority (81%) having ≤6 bands difference with the USA300-0114 strain. Representative isolates of this clone were ST8 but, unlike the USA300-0114 strain, they harbored a different SCCmec IV subtype and lacked arcA (an indicator of the arginine catabolic mobile element (ACME)). Conclusion A variant CA-MRSA USA300 clone has now become established in South America and, in some countries, is endemic in hospital settings. PMID:19911971

  4. Molecular detection and characterization of methicillin-resistant Staphylococcus aureus (MRSA) isolates from dogs in Portugal.

    PubMed

    Coelho, Céline; Torres, Carmen; Radhouani, Hajer; Pinto, Luís; Lozano, Carmen; Gómez-Sanz, Elena; Zaragaza, Myriam; Igrejas, Gilberto; Poeta, Patrícia

    2011-06-01

    Fifty-four healthy dogs were screened in Portugal for the presence of nasal methicillin-resistant Staphylococcus aureus (MRSA) carriage. Sixteen MRSA isolates (one/sample) were recovered from nasal samples of dogs, and they were typed by molecular methods (S. aureus protein A [spa]-, multilocus sequence typing-, staphylococcal cassette chromosome mec-typing). MRSA isolates were investigated for their susceptibility to antimicrobial agents by disk-diffusion test. The presence of resistance genes and of the Panton-Valentine leukocidin gene (lukF-lukS) was analyzed by PCR. Four different spa-types were identified among our MRSA isolates (t032, t432, t747, and t4726), with t032 as the most frequently detected. The sequence-type ST22 was identified in four tested MRSA isolates with different spa-types. All 16 isolates presented the staphylococcal cassette chromosome mec type IV. Most of MRSA isolates were resistant to ciprofloxacin, erythromycin, and clindamycin (94%-100%), and no resistance was identified to chloramphenicol, mupirocin, and trimethoprim-sulfametoxazole. The ermC and tetM resistance genes were detected in all MRSA isolates. The amino acid changes Ser84Leu in GyrA protein and Ser80Phe in GrlA protein were the most prevalent ones in our MRSA isolates. None of the MRSA strains carried the lukF-lukS genes. The results presented in this study indicate that healthy dogs may be a reservoir of MRSA that could be transmitted to humans by direct contact. PMID:21254810

  5. Molecular characterization of Staphylococcus aureus from nasal samples of healthy farm animals and pets in Tunisia.

    PubMed

    Gharsa, Haythem; Ben Slama, Karim; Gómez-Sanz, Elena; Lozano, Carmen; Zarazaga, Myriam; Messadi, Lilia; Boudabous, Abdellatif; Torres, Carmen

    2015-02-01

    A total of 261 healthy farm and pet animals (75 cattle, 52 goats, 100 dogs, and 34 cats) from different regions of Tunisia were screened for Staphylococcus aureus nasal carriage. Molecular typing of isolates (by spa- and multilocus sequence-typing) was performed, and their antimicrobial resistance and virulence genotypes were determined by PCR and sequencing. S. aureus isolates were detected in 17 of 261 tested samples (6.5%). All S. aureus isolates recovered were methicillin-susceptible (MSSA), and one isolate/sample was further studied. Eight different spa types were detected (t189, t279, t582, t701, t1166, t1268, t1534, and t1773), and eight different sequence types were identified (ST6, ST15, ST45, ST133, ST188, ST700 [clonal complex CC130], ST2057, and a new ST2121). MSSA from pets (six isolates) showed resistance to (number of isolates, resistance gene): penicillin (six, blaZ), tetracycline (one, tet[M]), erythromycin one, erm[A]), streptomycin (one, ant[6]-Ia), and ciprofloxacin (one). All isolates from farm animals showed susceptibility to the tested antimicrobials, except for two penicillin-resistant isolates. Five S. aureus isolates from goats and cats harbored the lukF/lukS-PV genes, encoding the Panton-Valentine leukocidin, and six isolates from goats harbored the tst virulence gene. In addition, diverse combinations of enterotoxin genes were detected, including two variants of the egc cluster. Goats and cats could represent a reservoir of important toxin genes, with potential implications in animal and human health. PMID:25700041

  6. Heterogeneity of disease and clones of community-onset methicillin-resistant Staphylococcus aureus in children attending a paediatric hospital in Belgium.

    PubMed

    Vergison, A; Nobre Machado, A; Deplano, A; Doyen, M; Brauner, J; Nonhoff, C; de Mendonça, R; Mascart, G; Denis, O

    2012-08-01

    The increase in the number of methicillin-resistant Staphylococcus aureus (MRSA) infections in children has prompted paediatricians to broaden th empirical treatment of common community-onset (CO) infections in children in several countries. Most European countries have reported low rates of CO-MRSA infection, but limited data on paediatric CO-MRSA infections are available. A prospective study was conducted from January 2002 to December 2004 in Brussels. CO-MRSA was defined as MRSA first detected by culture within 48 h of admission or in outpatients. Clinical and epidemiological data were recorded. CO-MRSA strains were genotyped by pulsed-field gel electrophoresis and multilocus sequence typing. Staphylococcal chromosomal cassette mec, toxin (Panton-Valentin leukocidin (PVL), toxic shock syndrome toxin 1, and Eta/b), enterotoxin and antibiotic resistance genes were detected by PCR. The antibiotic resistance phenotype was determined by disk diffusion. S. aureus was isolated in 1681 children. Among these, 107 harboured MRSA. Fifty-one children were colonized or infected by CO-MRSA, 20% of whom had no healthcare exposure. Twelve infants <3 months old and five cystic fibrosis patients were colonized. None of the 22 infected patients (59% with acute otitis media and 36% with skin and soft tissue infections (SSTIs)) required hospitalization. Two-thirds of them failed to respond to empirical antibiotic therapy. The 37 characterized CO-MRSA strains were genetically diverse. Most of them had healthcare-associated genotypes. Only six strains were PVL-positive, all of which were ciprofloxacin-susceptible and more common in children with SSTIs (p 0.001). CO-MRSA remains uncommon in our paediatric population. So far, there is no need to modify the empirical treatment of common S. aureus infections. Monitoring of MRSA rates in S. aureus CO infections remains mandatory, and further investigation is warranted to establish the source of colonization in young infants. PMID:21958085

  7. Structure-function analysis of heterodimer formation, oligomerization, and receptor binding of the Staphylococcus aureus bi-component toxin LukGH.

    PubMed

    Badarau, Adriana; Rouha, Harald; Malafa, Stefan; Logan, Derek T; Håkansson, Maria; Stulik, Lukas; Dolezilkova, Ivana; Teubenbacher, Astrid; Gross, Karin; Maierhofer, Barbara; Weber, Susanne; Jägerhofer, Michaela; Hoffman, David; Nagy, Eszter

    2015-01-01

    The bi-component leukocidins of Staphylococcus aureus are important virulence factors that lyse human phagocytic cells and contribute to immune evasion. The γ-hemolysins (HlgAB and HlgCB) and Panton-Valentine leukocidin (PVL or LukSF) were shown to assemble from soluble subunits into membrane-bound oligomers on the surface of target cells, creating barrel-like pore structures that lead to cell lysis. LukGH is the most distantly related member of this toxin family, sharing only 30-40% amino acid sequence identity with the others. We observed that, unlike other leukocidin subunits, recombinant LukH and LukG had low solubility and were unable to bind to target cells, unless both components were present. Using biolayer interferometry and intrinsic tryptophan fluorescence we detected binding of LukH to LukG in solution with an affinity in the low nanomolar range and dynamic light scattering measurements confirmed formation of a heterodimer. We elucidated the structure of LukGH by x-ray crystallography at 2.8-Å resolution. This revealed an octameric structure that strongly resembles that reported for HlgAB, but with important structural differences. Structure guided mutagenesis studies demonstrated that three salt bridges, not found in other bi-component leukocidins, are essential for dimer formation in solution and receptor binding. We detected weak binding of LukH, but not LukG, to the cellular receptor CD11b by biolayer interferometry, suggesting that in common with other members of this toxin family, the S-component has the primary contact role with the receptor. These new insights provide the basis for novel strategies to counteract this powerful toxin and Staphylococcus aureus pathogenesis. PMID:25371205

  8. High Resolution Magnetic and Gravity Surveys to Constrain Maar Geometry and Eruption Mechanisms, Rattlesnake Crater, Arizona

    NASA Astrophysics Data System (ADS)

    Marshall, A. M.; Kruse, S. E.; Connor, C.; Connor, L.; Abdollahzadeh, M.; Harburger, A.; Richardson, J. A.; Courtland, L. M.; Farrell, A. K.; Kiflu, H. G.; Malservisi, R.; McNiff, C. M.; Njoroge, M.; Nushart, N.; Rookey, K.

    2013-12-01

    Located 25 kilometers east of Flagstaff, Arizona, Rattlesnake Crater is an oblong phreatomagmatic feature in the San Francisco Volcanic Field. The shallow crater is approximately 1.4 kilometers at its widest point, and surrounded by an uneven tuff ring which is overlapped by a scoria cone volcano on the southeastern side. Improved understanding of its formation and evolution requires geophysical study because there are very few outcrops, and no digging is permitted on site. Geologic features related to the crater are further obscured by deposits from the overlapping scoria cone, as well as tephra from eruptions at nearby Sunset Crater. We present the results of a detailed magnetic and gravity survey in and around Rattlesnake Crater. A substantial NW-SE trending elongate magnetic anomaly (1400 nT) and a smaller similarly trending anomaly are observed inside the crater, as well as a longer wavelength positive gravitational anomaly (+1.0-1.5 mGal) across the crater. The magnetic survey was completed on foot with a 50 meter line spacing inside the crater, and 100 meter line spacing across a portion of the surrounding area outside the crater. The gravity survey was done on two intersecting survey lines - one running west to east, and another roughly north to south, with recordings every 100 meters extending at least 1000 meters outside the crater in all four directions. 2D models of the magnetic and gravity data are presented illustrating the possible geometry of the diatreme, and the approximate size and shape of the major intrusive features. Eruption estimates based on the models are calculated, and the models are favorably compared to the size and depth estimates given in a recent publication (Valentine 2012) that used xenolith content to estimate the size and depth of the diatreme.

  9. agr Dysfunction Affects Staphylococcal Cassette Chromosome mec Type-Dependent Clinical Outcomes in Methicillin-Resistant Staphylococcus aureus Bacteremia

    PubMed Central

    Kang, Chang Kyung; Cho, Jeong Eun; Choi, Yoon Jeong; Jung, Younghee; Kim, Nak-Hyun; Kim, Chung-Jong; Kim, Taek Soo; Song, Kyoung-Ho; Choe, Pyoeng Gyun; Park, Wan Beom; Bang, Ji-Hwan; Kim, Eu Suk; Park, Kyoung Un; Park, Sang Won; Kim, Nam-Joong; Oh, Myoung-don

    2015-01-01

    Staphylococcal cassette chromosome mec element (SCCmec) type-dependent clinical outcomes may vary due to geographical variation in the presence of virulence determinants. We compared the microbiological factors and mortality attributed to methicillin-resistant Staphylococcus aureus (MRSA) bacteremia between SCCmec types II/III and type IV. All episodes of MRSA bacteremia in a tertiary-care hospital (South Korea) over a 4.5-year period were reviewed. We studied the microbiological factors associated with all blood MRSA isolates, including spa type, agr type, agr dysfunction, and the genes for Panton-Valentine leukocidin (PVL) and phenol-soluble modulin (PSM)-mec, in addition to SCCmec type. Of 195 cases, 137 involved SCCmec types II/III, and 58 involved type IV. The mortality attributed to MRSA bacteremia was less frequent among the SCCmec type IV (5/58) than that among types II/III (39/137, P = 0.002). This difference remained significant when adjusted for clinical factors (adjusted odds ratio [aOR], 0.14; 95% confidence interval [CI], 0.04 to 0.49; P = 0.002). Of the microbiological factors tested, agr dysfunction was the only significant factor that showed different positivity between the SCCmec types, and it was independently associated with MRSA bacteremia-attributed mortality (aOR, 4.71; 95% CI, 1.72 to 12.92; P = 0.003). SCCmec type IV is associated with lower MRSA bacteremia-attributed mortality than are types II/III, which might be explained by the high rate of agr dysfunction in SCCmec types II/III in South Korea. PMID:25779574

  10. PREFACE: International Conference on Theoretical Physics: Dubna-Nano 2012

    NASA Astrophysics Data System (ADS)

    Osipov, Vladimir; Nesterenko, Valentin; Shukrinov, Yury M.

    2012-11-01

    The International Conference 'Dubna-Nano2012' was held on 9-14 July 2012 at the Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Moscow region, Russia. The conference was the third one in the series started in 2008. 'Dubna-Nano2012' provided an opportunity for presentations and discussions about theoretical and experimental advances in the rapidly growing area of nanophysics. The multidisciplinary character of the conference allowed an effective exchange of ideas between different areas of nanophysics. The following topics were covered: graphene and other carbon nanostructures, topological insulators, quantum transport, quantum dots, atomic clusters, Josephson junctions and applications of nanosystems. About 100 scientists from 22 countries participated in the conference. The program included 38 oral talks and 39 posters. This volume contains 35 contributions. We would like to express our gratitude to all participants for their presentations and discussions. We are deeply indebted to the members of the International Advisory Committee Professors K S Novoselov, T Ando, T Chakraborty, J Fabian, V M Galitski, F Guinea, M Z Hasan, P Hawrylak, K Kadowaki, R Kleiner, T Koyama, Yu I Latyshev, Yu E Lozovik, M Machida, B K Nikolic, N F Pedersen, P-G. Reinhard, J M Rost and A Ya Vul. Financial support from BLTP JINR, Russian Foundation for Basic Research, Heisenberg-Landau Program and Bogoliubov-Infeld Program was of a great importance. Further information about 'Dubna-Nano2012' is available on the homepage http://theor.jinr.ru/~nano12. Vladimir Osipov, Valentin Nesterenko and Yury Shukrinov Editors

  11. PREFACE International Conference on Theoretical Physics Dubna-Nano 2010

    NASA Astrophysics Data System (ADS)

    Osipov, Vladimir; Nesterenko, Valentin; Shukrinov, Yury

    2010-11-01

    The International Conference on Theoretical Physics 'Dubna-Nano2010' was held on 5-10 July 2010, at the Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Moscow region, Russia. The previous conference of this series was at Dubna in 2008. The conference provided the opportunity for the presentation and discussion of theoretical and experimental advances in the rapidly growing area of nanophysics, with the accent on its theoretical aspects. The multidisciplinary character of the conference allowed an effective exchange of ideas between different areas of nanophysics. The following topics were covered: carbon nanosystems (graphene, nanotubes, fullerenes), quantum dots, quantum transport, spectroscopy and dynamics of atomic clusters, Josephson junctions, modelling, applications and perspectives. Approximately 120 scientists from 26 countries participated in the conference. The program included 63 oral talks and 70 posters. The 62 contributions are included in these proceedings. We would like to express our gratitude to all participants for their presentations and discussions, which made the conference indeed successful. We are deeply indebted to the members of the International Advisory Committee (Professors T Ando, J Fabian, F Guinea, P Hawrylak, K Kadowaki, T Koyama, Yu I Latushev, Yu E Lozovik, M Machida, B K Nikolic, N F Pedersen, P-G Reinhard, J M Rost, A Ya Vul') and the Local Organizing Committee for their fruitful work. The financial support of BLTP JINR, Russian Foundation for Basic Research, Heisenberg-Landau Program and Bogoliubov-Infeld Program was of a great importance. Additional information about 'Dubna-Nano2010' is available at the homepage http://theor.jinr.ru/~nano10. Vladimir Osipov, Valentin Nesterenko and Yury Shukrinov Editors

  12. Phenotypic and genotypic detection of virulence factors of Staphylococcus aureus isolated from clinical and subclinical mastitis in cattle and water buffaloes from different farms of Sadat City in Egypt

    PubMed Central

    Elsayed, Mohamed Sabry; Mahmoud El-Bagoury, Abd Elrahman; Dawoud, Mai Abdallah

    2015-01-01

    Aim: To characterize Staphylococcus aureus from clinical and subclinical mastitis and identify virulence factors. Materials and Methods: Two hundred and two milk samples were collected, 143 from mastitic cattle and buffaloes 94 and 49, respectively, and 59 from apparently healthy cattle and buffaloes 35 and 24, respectively. Results: California mastitis test was applied and positive prevalence were 91.48% and 75.51% for cattle and buffalo with clinical mastitis and 37.14% and 45.83% for cattle and buffalo with subclinical mastitis. S. aureus was isolated from clinically mastitic cattle and buffaloes were 39.29% and 50%, respectively. While, from subclinical mastitic cattle and buffaloes were 80% and 72.73%, respectively. Hemolytic activity was assessed for S. aureus isolated from clinically and subclinical mastitic cases with prevalences of 100% and 56.25%, respectively. Thermo nuclease production from clinically and subclinical mastitic cases was 25% and 56.25%, respectively. Simplex polymerase chain reaction (PCR) conducted on S. aureus using 16S rRNA, clumping factor A, Panton valentine leukocidin, coagulase (Coa), alpha-hemolysin and beta-hemolysin those proved existence in 100%, 46.9%, 65.6%, 100%, 34.4%, and 43.75% of the isolates, respectively. While, multiplex PCR is utilized for detection of enterotoxins and proved that 12.5% was positive for enterotoxine Type D. Conclusions: It is concluded that simplex and multiplex PCR assays can be used as rapid and sensitive diagnostic tools to detect the presence of S. aureus and characterize its virulence factors that help in detection of severity of infection, distribution and stating preventive and control strategies. PMID:27047197

  13. Differentiation of clonal complex 59 community-associated methicillin-resistant Staphylococcus aureus in Western Australia.

    PubMed

    Coombs, Geoffrey W; Monecke, Stefan; Ehricht, Ralf; Slickers, Peter; Pearson, Julie C; Tan, Hui-Leen; Christiansen, Keryn J; O'Brien, Frances G

    2010-05-01

    Clonal complex 59 (CC59) community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strains were characterized using pulsed-field gel electrophoresis, spa typing, multilocus sequence typing, diagnostic DNA microarrays, and PCRs targeting staphylococcal cassette chromosome mec (SCCmec) elements and Panton-Valentine leukocidin (PVL). Six distinct groups within CC59 were characterized. At least seven different variants of SCCmec elements were identified (IVa [2B], IVb [2B], IVd [2B], IV variant [2B], IVa [2B&5], V variant [5C2], and V [5C2&5]). (The structural type is indicated by a Roman numeral, with a lowercase letter indicating the subtype, and the ccr complex and the mec complex are indicated by an Arabic numeral and an uppercase letter, respectively. Where there is an extra ccr element, this is indicated by "&" and an Arabic numeral designating the ccr type.) The first group is similar to the American sequence type 59 (ST59) MRSA-IV CA-MRSA strain USA1000. The second group includes a PVL-negative ST87 strain with an SCCmec element of subtype IVb (2B). The third group comprises PVL-variable ST59 MRSA-IV strains harboring multiple SCCmec IV subtypes. PVL-negative ST59 MRSA strains with multiple or composite SCCmec elements (IVa [2B&5]) form the fourth group. Group 5 corresponds to the internationally known "Taiwan clone," a PVL-positive strain with a variant SCCmec element (V [5C2&5]). This strain proved to be the most common CC59 MRSA strain isolated in Western Australia. Finally, group 6 encompasses the ST59 MRSA-V variant (5C2). The differentiation of CC59 into groups and strains indicates a rapid evolution and spread of SCCmec elements. Observed differences between groups of strains as well as intrastrain variability within a group facilitate the tracing of their spread. PMID:20211891

  14. The Role of Familiarity for Representations in Norm-Based Face Space

    PubMed Central

    Faerber, Stella J.; Kaufmann, Jürgen M.; Leder, Helmut; Martin, Eva Maria; Schweinberger, Stefan R.

    2016-01-01

    According to the norm-based version of the multidimensional face space model (nMDFS, Valentine, 1991), any given face and its corresponding anti-face (which deviates from the norm in exactly opposite direction as the original face) should be equidistant to a hypothetical prototype face (norm), such that by definition face and anti-face should bear the same level of perceived typicality. However, it has been argued that familiarity affects perceived typicality and that representations of familiar faces are qualitatively different (e.g., more robust and image-independent) from those for unfamiliar faces. Here we investigated the role of face familiarity for rated typicality, using two frequently used operationalisations of typicality (deviation-based: DEV), and distinctiveness (face in the crowd: FITC) for faces of celebrities and their corresponding anti-faces. We further assessed attractiveness, likeability and trustworthiness ratings of the stimuli, which are potentially related to typicality. For unfamiliar faces and their corresponding anti-faces, in line with the predictions of the nMDFS, our results demonstrate comparable levels of perceived typicality (DEV). In contrast, familiar faces were perceived much less typical than their anti-faces. Furthermore, familiar faces were rated higher than their anti-faces in distinctiveness, attractiveness, likability and trustworthiness. These findings suggest that familiarity strongly affects the distribution of facial representations in norm-based face space. Overall, our study suggests (1) that familiarity needs to be considered in studies of mental representations of faces, and (2) that familiarity, general distance-to-norm and more specific vector directions in face space make different and interactive contributions to different types of facial evaluations. PMID:27168323

  15. Use of oligoarrays for characterization of community-onset methicillin-resistant Staphylococcus aureus.

    PubMed

    Koessler, Thibaud; Francois, Patrice; Charbonnier, Yvan; Huyghe, Antoine; Bento, Manuela; Dharan, Sasi; Renzi, Gesuele; Lew, Daniel; Harbarth, Stephan; Pittet, Didier; Schrenzel, Jacques

    2006-03-01

    Until recently, methicillin-resistant Staphylococcus aureus (MRSA) was considered the prototype of a hospital-acquired bacterial pathogen. However, recent reports have shown that MRSA has now emerged in the community. Characterization of specific markers for distinguishing the origin of isolates could contribute to improved knowledge of MRSA epidemiology. The release of whole-genome sequences of hospital- and community-acquired S. aureus strains allowed the development of whole-genome content analysis techniques, including microarrays. We developed a microarray composed of 8,191 open reading frame-specific oligonucleotides covering >99% of the four sequenced S. aureus genomes (N315, Mu50, MW2, and COL) to evaluate gene contents of hospital- and community-onset S. aureus strains. In parallel, pulsed-field gel electrophoresis, variable number of tandem repeats, antibiogram, staphylococcal cassette chromosome-mec element typing, and presence of the Panton-Valentine leukocidin gene were evaluated in a collection of 15 clinical isolates. Clusters obtained with microarrays showed a high degree of similarity with those obtained by pulsed-field gel electrophoresis or variable number of tandem repeats. Clusters clearly segregated hospital-onset strains from community-onset strains. Moreover, the microarray approach allowed definition of novel marker genes and chromosomal regions specific for given groups of isolates, thus providing better discrimination and additional information compared to pulsed-field gel electrophoresis and variable number of tandem repeats. Finally, the comparative genome hybridization approach unraveled the occurrence of multiple horizontal transfer events leading to community-onset MRSA as well as the need for a specific genetic background in recipient strains for both the acquisition and the stability of the mec element. PMID:16517892

  16. Use of Oligoarrays for Characterization of Community-Onset Methicillin-Resistant Staphylococcus aureus

    PubMed Central

    Koessler, Thibaud; Francois, Patrice; Charbonnier, Yvan; Huyghe, Antoine; Bento, Manuela; Dharan, Sasi; Renzi, Gesuele; Lew, Daniel; Harbarth, Stephan; Pittet, Didier; Schrenzel, Jacques

    2006-01-01

    Until recently, methicillin-resistant Staphylococcus aureus (MRSA) was considered the prototype of a hospital-acquired bacterial pathogen. However, recent reports have shown that MRSA has now emerged in the community. Characterization of specific markers for distinguishing the origin of isolates could contribute to improved knowledge of MRSA epidemiology. The release of whole-genome sequences of hospital- and community-acquired S. aureus strains allowed the development of whole-genome content analysis techniques, including microarrays. We developed a microarray composed of 8,191 open reading frame-specific oligonucleotides covering >99% of the four sequenced S. aureus genomes (N315, Mu50, MW2, and COL) to evaluate gene contents of hospital- and community-onset S. aureus strains. In parallel, pulsed-field gel electrophoresis, variable number of tandem repeats, antibiogram, staphylococcal cassette chromosome-mec element typing, and presence of the Panton-Valentine leukocidin gene were evaluated in a collection of 15 clinical isolates. Clusters obtained with microarrays showed a high degree of similarity with those obtained by pulsed-field gel electrophoresis or variable number of tandem repeats. Clusters clearly segregated hospital-onset strains from community-onset strains. Moreover, the microarray approach allowed definition of novel marker genes and chromosomal regions specific for given groups of isolates, thus providing better discrimination and additional information compared to pulsed-field gel electrophoresis and variable number of tandem repeats. Finally, the comparative genome hybridization approach unraveled the occurrence of multiple horizontal transfer events leading to community-onset MRSA as well as the need for a specific genetic background in recipient strains for both the acquisition and the stability of the mec element. PMID:16517892

  17. Levels of alpha-toxin correlate with distinct phenotypic response profiles of blood mononuclear cells and with agr background of community-associated Staphylococcus aureus isolates.

    PubMed

    Mairpady Shambat, Srikanth; Haggar, Axana; Vandenesch, Francois; Lina, Gerard; van Wamel, Willem J B; Arakere, Gayathri; Svensson, Mattias; Norrby-Teglund, Anna

    2014-01-01

    Epidemiological studies of Staphylococcus aureus have shown a relation between certain clones and the presence of specific virulence genes, but how this translates into virulence-associated functional responses is not fully elucidated. Here we addressed this issue by analyses of community-acquired S. aureus strains characterized with respect to antibiotic resistance, ST types, agr types, and virulence gene profiles. Supernatants containing exotoxins were prepared from overnight bacterial cultures, and tested in proliferation assays using human peripheral blood mononuclear cells (PBMC). The strains displayed stable phenotypic response profiles, defined by either a proliferative or cytotoxic response. Although, virtually all strains elicited superantigen-mediated proliferative responses, the strains with a cytotoxic profile induced proliferation only in cultures with the most diluted supernatants. This indicated that the superantigen-response was masked by a cytotoxic effect which was also confirmed by flow cytometry analysis. The cytotoxic supernatants contained significantly higher levels of α-toxin than did the proliferative supernatants. Addition of α-toxin to supernatants characterized as proliferative switched the response into cytotoxic profiles. In contrast, no effect of Panton Valentine Leukocidin, δ-toxin or phenol soluble modulin α-3 was noted in the proliferative assay. Furthermore, a significant association between agr type and phenotypic profile was found, where agrII and agrIII strains had predominantly a proliferative profile whereas agrI and IV strains had a predominantly cytotoxic profile. The differential response profiles associated with specific S. aureus strains with varying toxin production could possibly have an impact on disease manifestations, and as such may reflect specific pathotypes. PMID:25166615

  18. Increase in SCCmec type IV strains affects trends in antibiograms of meticillin-resistant Staphylococcus aureus at a tertiary-care hospital.

    PubMed

    Ito, Ayumu; Nakaminami, Hidemasa; Fujii, Takeshi; Utsumi, Kenta; Noguchi, Norihisa

    2015-07-01

    The prevalence of community-acquired meticillin-resistant Staphylococcus aureus (CA-MRSA) strains has become a serious problem worldwide. The aim of this study was to investigate the annual transitions of MRSA strains with the CA-MRSA feature, which were identified as SCCmec type IV or V, in a hospital setting in Japan. Between 2005 and 2012, MRSA strains were collected from a tertiary-care hospital in Tokyo, Japan, and SCCmec typing, detection of the virulence factors and antimicrobial susceptibility testing were conducted. The rate of detection of type II SCCmec, which is found mainly in healthcare-associated MRSA, significantly decreased from 90.0 (2005-2006) to 74.3 % (2011-2012) (P < 0.01). In contrast, the rate of detection of type IV SCCmec, which is mainly found in CA-MRSA, significantly increased from 5.8 (2005-2006) to 16.3 % (2011-2012) (P < 0.01). The rate of detection of the toxic shock syndrome toxin-1 gene significantly decreased from 66.7 (2005-2006) to 51.6 % (2011-2012) (P < 0.01), whilst that of the Panton-Valentine leukocidin gene significantly increased from 0.1 (2005-2006) to 2.1 % (2011-2012) (P < 0.01). The resistance rates of cefotaxime, levofloxacin, clarithromycin and minocycline decreased every year. The resistance rates of these antimicrobial agents for the SCCmec type IV or V strains were significantly lower than those for the SCCmec type I or II strains (P < 0.01, respectively). Therefore, these results suggest that the annual transitions of the virulence factors and antibiograms in MRSA are closely related to the increase of SCCmec type IV/V strains. PMID:25934550

  19. Identification and characterization of methicillin-resistant Staphylococcus aureus (MRSA) from Austrian companion animals and horses.

    PubMed

    Loncaric, Igor; Künzel, Frank; Licka, Theresia; Simhofer, Hubert; Spergser, Joachim; Rosengarten, Renate

    2014-01-31

    The aim of this study was to investigate the antimicrobial resistance, resistance gene patterns and genetic relatedness of a collection of Austrian methicillin-resistant Staphylococcus aureus (MRSA) isolates from companion animals and horses. A total of 89 non-repetitive MRSA isolates collected during routine veterinary microbiological examinations from April 2004 to the end of 2012, and one isolate from 2013 were used for this study. The presence of mecA and other resistance genes was confirmed by PCR. Isolates were genotyped by spa typing, two multiple-locus variable-number tandem repeat analyses (MLVA) analyses, SCCmec typing and multilocus sequence typing (MLST). PCR targeting Panton-Valentine leukocidin (PVL) and detection of staphylococcal enterotoxins (SE), toxic shock syndrome toxin (TSST) was performed using PCR assays. Antimicrobial susceptibility testing was performed. Five sequence types (STs-ST398, ST254, ST22, ST5 and ST1), SCCmec types II, IVa, V, and non-type-abele, 8 spa-types (t003, t011, t036, t127, t386, t1348, and t4450), and two isolates could not be assigned, 21 MLVA-14Orsay types Multiplex-PCR MLVA (mMLVA) displayed 17 different MLVA types. The present study is the most comprehensive dealing with MRSA from Austrian companion animals and horses. The results confirm that MRSA ST398 is present in a wide range of animal species and is predominant especially in horses. In other companion animals it is unclear whether the infections with the different MRSA isolates investigated in the present study truly represents a rare phenomenon or may be an emerging problem in companion animals. PMID:24332703

  20. Classical theory of atomic collisions - The first hundred years

    NASA Astrophysics Data System (ADS)

    Grujić, Petar V.

    2012-05-01

    Classical calculations of the atomic processes started in 1911 with famous Rutherford's evaluation of the differential cross section for α particles scattered on foil atoms [1]. The success of these calculations was soon overshadowed by the rise of Quantum Mechanics in 1925 and its triumphal success in describing processes at the atomic and subatomic levels. It was generally recognized that the classical approach should be inadequate and it was neglected until 1953, when the famous paper by Gregory Wannier appeared, in which the threshold law for the single ionization cross section behaviour by electron impact was derived. All later calculations and experimental studies confirmed the law derived by purely classical theory. The next step was taken by Ian Percival and collaborators in 60s, who developed a general classical three-body computer code, which was used by many researchers in evaluating various atomic processes like ionization, excitation, detachment, dissociation, etc. Another approach was pursued by Michal Gryzinski from Warsaw, who started a far reaching programme for treating atomic particles and processes as purely classical objects [2]. Though often criticized for overestimating the domain of the classical theory, results of his group were able to match many experimental data. Belgrade group was pursuing the classical approach using both analytical and numerical calculations, studying a number of atomic collisions, in particular near-threshold processes. Riga group, lead by Modris Gailitis [3], contributed considerably to the field, as it was done by Valentin Ostrovsky and coworkers from Sanct Petersbourg, who developed powerful analytical methods within purely classical mechanics [4]. We shall make an overview of these approaches and show some of the remarkable results, which were subsequently confirmed by semiclassical and quantum mechanical calculations, as well as by the experimental evidence. Finally we discuss the theoretical and

  1. A variant of the Southern German clone of methicillin-resistant Staphylococcus aureus is predominant in Croatia.

    PubMed

    Budimir, A; Deurenberg, R H; Bosnjak, Z; Stobberingh, E E; Cetkovic, H; Kalenic, S

    2010-08-01

    The aim of the present study was to investigate the antibiotic susceptibility patterns and molecular epidemiology of clinical methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered in 24 hospitals in 20 cities in Croatia from October to December 2004. A total of 1815 consecutive S. aureus isolates were recovered, 248 of which were MRSA. The MRSA isolates were analysed using spa typing, multilocus sequence typing and SCCmec typing. Furthermore, the presence of Panton-Valentine leukocidin (PVL) genes was determined as a genetic marker for community-associated MRSA. The MRSA prevalence was 14%. Ninety-six per cent of the MRSA isolates were resistant to ciprofloxacin, 95% to clindamycin and azithromycin, 94% to gentamicin, and 93% to erythromycin. The majority of the MRSA isolates (78%) was associated with the ST111-MRSA-I clone. In addition, various other endemic MRSA clones were observed, such as the ST247-MRSA-I (4%), the ST45-MRSA-IV (2%), the ST5-MRSA-I (2%), the ST239-MRSA-III (2%), the ST5-MRSA-II (1%), the ST8-MRSA-IV (1%) and the ST5-MRSA-IV (<1%) clones. Furthermore, we observed one PVL-negative ST80-MRSA-IV isolate. Four PVL-positive MRSA isolates were found, associated with ST8-MRSA-IV, ST80-MRSA-IV and ST80-MRSA-I. The ST111-MRSA-I clone was predominant in Croatia. Future surveillance studies of MRSA are important to elucidate whether changes in the clonal distribution of MRSA will occur, and if the minor endemic MRSA clones observed in the present study will replace the ST111-MRSA-I clone on a large scale. PMID:19732087

  2. List of Organizing Committees and Conference Programme

    NASA Astrophysics Data System (ADS)

    2012-03-01

    Organizers Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN HH Romanian Neutron Scattering Society Sponsors Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN HH Comenius University in Bratislava, Slovakia Institute of Macromolecular Chemistry AS CR, Czech Republic Programme Committee Valentin Gordely (chairman)Joint Institute for Nuclear Research, Russia Heinrich StuhrmannGermany Jose TeixeiraLaboratoire Leon Brillouin, France Pavel ApelJoint Institute for Nuclear Research, Russia Pavol BalgavyComenius University in Bratislava, Slovakia Alexander BelushkinJoint Institute for Nuclear Research, Russia Georg BueldtInstitute of Structural Biology and Biophysics (ISB), Germany Leonid BulavinTaras Shevchenko National University of Kyiv, Ukraine Emil BurzoBabes-Bolyai University, Romania Vadim CherezovThe Scripps Research Institute, Department of Molecular Biology, USA Ion IonitaRomanian Society of Neutron Scattering, Romania Alexei KhokhlovMoscow State University, Russia Aziz MuzafarovInstitute of Synthetic Polymeric Materials, Russian Academy of Sciences, Russia Alexander OzerinInstitute of Synthetic Polymeric Materials, Russian Academy of Sciences, Russia Gerard PepyResearch Institute for Solid State Physics and Optics, Hungary Josef PlestilInstitute of Macromolecular Chemistry CAS, Czech Republic Aurel RadulescuJuelich Centre for Neutron Science JCNS, Germany Maria BalasoiuJoint Institute for Nuclear Research, Russia Alexander KuklinJoint Institute for Nuclear Research, Russia Local Organizing Committee Alexander Kuklin - Chairman Maria Balasoiu - Co-chairman Tatiana Murugova - Secretary Natalia Malysheva Natalia Dokalenko Julia Gorshkova Andrey Rogachev Oleksandr Ivankov Dmitry Soloviev Lilia Anghel Erhan Raul The PDF also contains the Conference Programme.

  3. Methicillin-resistant Staphylococcus aureus with mecC: a description of 45 human cases in southern Sweden.

    PubMed

    Lindgren, A-K; Gustafsson, E; Petersson, A C; Melander, E

    2016-06-01

    In 2011, a novel mecA gene homologue, mecC, was reported in isolates from both humans and dairy cattle. The epidemiology of mecC methicillin-resistant Staphylococcus aureus (MRSA) in humans is not yet well known. In this retrospective study, we present the epidemiology of human clinical cases with mecC MRSA detected in the southern part of Sweden during the period 2005-2014. A total of 45 patients with an isolate positive for mecC MRSA were included in the study. Twenty-six isolates were found before 2012 and were retrospectively tested for mecC. Nineteen isolates were detected in 2012-2014 through routine testing. Culture results, resistance patterns, Panton-Valentine leukocidin (PVL) genes, and spa types were collected from the Clinical Microbiology Laboratory. Epidemiological data were received from the database at the Regional Centre for Communicable Disease Control and the patient's medical files. The majority of the patients with mecC MRSA were of Swedish origin, had underlying diseases, and lived in rural areas. The median age was 60 years. Of the mecC MRSA, 76 % belonged to spa types t373 and t843. The median minimum inhibitory concentration (MIC) value for oxacillin was 16 mg/L (1-64 mg/L) and only one isolate was resistant to other classes of antibiotics. The most common type of infection was skin and soft tissue infections, most often in an existing skin lesion. The patients with mecC MRSA were colonized for a short time and gave rise to few secondary cases. mecC MRSA in our region appears to have a domestic origin and mainly affects patients with underlying diseases or patients with an existing skin lesion. Our data indicate that it could be a poor colonizer. PMID:27010813

  4. Nasal Carriage of Staphylococcus aureus in Botucatu, Brazil: A Population-Based Survey

    PubMed Central

    Pires, Fabiana Venegas; da Cunha, Maria de Lourdes Ribeiro de Souza; Abraão, Lígia Maria; Martins, Patrícia Y. F.; Camargo, Carlos Henrique; Fortaleza, Carlos Magno Castelo Branco

    2014-01-01

    Recent increases in the incidence and severity of staphylococcal infections renewed interest in studies that assess the burden of asymptomatic carriage of Staphylococcus aureus in the community setting. We conducted a population-based survey in the city of Botucatu, Brazil (122,000 inhabitants), in order to identify the prevalence of nasal carriage of Staphylococcus aureus (including methicillin-resistant strains). Nasal swabs were obtained from 686 persons over one year of age. Resistance to methicillin was assessed through phenotypic methods, identification of the mecA gene and typing of the Staphylococcal Chromosome Cassette mec (SCCmec). Methicillin-resistant S. aureus (MRSA) isolates were characterized using Pulsed-Field Gel Electrophoresis (PFGE), Multilocus Sequence Typing (MLST) and spa typing. Polymerase chain reaction was applied to identify genes coding for Panton-Valentine Leukocidin (PVL) in isolates. The prevalence of overall S. aureus carriage was 32.7% (95%CI, 29.2%–36.2%). Carriers were significantly younger (mean age, 28.1 versus 36.3 for non-carriers; OR for age, 0.98; 95%CI, 0.97–0.99) and likely to report recent skin infection (OR, 1.85; 95%CI, 1.03–3.34). Carriage of methicillin-resistant S. aureus (MRSA) was found in 0.9% of study subjects (95%CI, 0.4%–1.8%). All MRSA isolates harbored SCCmec type IV, and belonged to spa types t002 or t021, but none among them harbored genes coding for PLV. In MLST, most isolates belonged to clones ST5 or ST1776. However, we found one subject who carried a novel clone, ST2594. Two out of six MRSA carriers had household contacts colonized with isolates similar to theirs. Our study pointed to dissemination of community-associated MRSA among the Brazilian population. PMID:24663818

  5. Polyclonal non multiresistant methicillin resistant Staphylococcus aureus isolates from clinical cases of infection occurring in Palermo, Italy, during a one-year surveillance period

    PubMed Central

    2012-01-01

    Background The evolving epidemiology of methicillin resistant Staphylococcus aureus (MRSA) is characterized by the emergence of infections caused by non multiresistant MRSA carrying staphylococcal chromosomal cassette (SCC)mec IV or V in the healthcare settings. A molecular epidemiological analysis of non multiresistant MRSA isolates from four acute general hospitals was performed in Palermo, Italy, during a one year period. Methods For the purpose of the study, MRSA isolates were defined as non multiresistant when they were susceptible to at least three classes of non β-lactam antibiotics. Seventy-five isolates were submitted to antimicrobial susceptibility testing, multilocus sequence typing (MLST) and polymerase chain reaction (PCR) for SCCmec, accessory gene regulator (agr) groups, arginine catabolic mobile element (ACME) and Panton Valentine leukocidin (PVL) toxin genes. For epidemiological typing, Multiple-Locus Variable-Number Tandem Repeat Fingerprinting (MLVF) was performed on all isolates and pulsed field gel electrophoresis (PFGE) on ST8 isolates. Results Non multiresistant MRSA isolates were isolated from all hospitals. Resistances to ciprofloxacin, macrolides and tetracycline were the most prevalent. MLST attributed 46 isolates with ST22, 13 with ST8, eight with ST1, three with ST50 and three with ST398. SCCmec type IV was found in all isolates. PVL was detected in one ST22 isolate. All isolates tested negative for the ACME element. MLVF identified 31 different patterns, some subtype clusters ranging in size between two and 22 isolates. The closely related PFGE patterns of the ST8 isolates differed from USA300. Conclusions A polyclonal circulation of non multiresistant MRSA along with blurring of boundaries between healthcare associated (HA)-MRSA and community associated (CA)-MRSA appear to be occurring in our epidemiological setting. A better understanding of spread of MRSA with the support of molecular typing can provide invaluable information in

  6. Methicillin-Resistant Staphylococcus aureus Ocular Infection in Taiwan

    PubMed Central

    Kang, Yu-Chuan; Hsiao, Ching-Hsi; Yeh, Lung-Kun; Ma, David H.K.; Chen, Phil Y.F.; Lin, Hsin-Chiung; Tan, Hsin-Yuan; Chen, Hung-Chi; Chen, Shin-Yi; Huang, Yhu-Chering

    2015-01-01

    Abstract Methicillin-resistant Staphylococcus aureus (MRSA) infection is an important public health issue. This observational study aimed to characterize clinical features, antibiotic susceptibility, and genotypes of ocular infections caused by MRSA based on the clinical and molecular definitions of community-associated (CA) and healthcare-associated (HA) strains. Fifty-nine patients with culture-proven S aureus ocular infection were enrolled from January 1, 2010 to December 31, 2011 at Chang Gung Memorial Hospital, Taiwan. Antibiotic susceptibility was verified using disk diffusion/E test. For characterization, staphylococcal cassette chromosome mec (SCCmec), pulsed-field gel electrophoresis (PFGE), multilocus sequence type (MLST), and Panton–Valentine leukocidin (PVL) gene, were performed. MRSA isolates from the patients with HA factors were classified as clinically defined HA-MRSA, and those carrying SCCmec type I to III as molecularly defined HA-MRSA. Thirty-four patients with MRSA ocular infection were identified. The most common clone of CA-MRSA and HA-MRSA isolates was ST59/PFGE type D/SCCmec IV,VT/PVL (+) (n = 12) and CC 239/PFGE type A/SCCmec III, IIIA/PVL(−) (n = 10), respectively. All the 11 patients with molecularly defined HA-MRSA infections and 50% of the 22 patients with molecularly defined CA-MRSA infections were found to have HA factors (P = .005). CA-MRSA tended to cause lid infections, whereas HA-MRSA tended to cause corneal infections. Contrary to HA-MRSA isolates, nearly all the CA-MRSA isolates were susceptible to trimethoprim/sulfamethoxazole and fluoroquinolones under either clinical or molecular classifications. In Taiwan, CA-MRSA isolates exhibited considerably higher susceptibility to fluoroquinolones when compared with HA-MRSA isolates. A strong correlation was observed between the HA factors and molecularly defined HA-MRSA isolates. PMID:26496268

  7. Quaternary faults near the proposed Eagle Flat low-level radioactive waste repository, Trans-Pecos Texas

    SciTech Connect

    Collins, E.W.; Raney, J.A. . Bureau of Economic Geology)

    1992-01-01

    The Eagle Flat basin, an intermontane basin in Trans-Pecos Texas, is being considered as a possible site for the Texas repository of low-level radioactive wastes. Intermontane basins and associated normal faults formed in response to Basin and Range tectonism that began about 24 Ma ago. The most active late Tertiary and Quaternary faults occur within the Hueco Bolson (HB) and the Salt Basin/Salt Flat/Lobo Valley, west and east, respectively, of the proposed repository. Several faults of the southeast HB which are within 50 km of the site, displace middle Pleistocene deposits 10 to 24 m. The most recent surface rupture in the southeast HB probably occurred on the Amargosa fault during the Holocene. Upper Pleistocene deposits are offset 2.5 to 4.5 m, and middle Pleistocene deposits are displaced 24 m. Fault scarps within 50 km east of the proposed repository are associated with faults bounding the Salt Basin/Salt Flat/Lobo Valley. In the southern Salt Basin and northern Salt Flat, faults offset probable upper Pleistocene to Holocene deposits as much as 1.5 m. A scarp in Red Light Bolson, 13.5 km south of the site, is the closest Quaternary fault scarp to the proposed site. Only 7 km long, this scarp is part of a mostly covered, probably multisegmented, 40-km-long fault that bounds the northeastern margin of Red Light Bolson. Offsets associated with single-rupture events range from 0.6 to 3 m, and average recurrence intervals between surface ruptures since middle Pleistocene are about 10,000 to 100,000 yr. The largest historical earthquake of the region, the 1931 Valentine earthquake, which had a magnitude of 6.4 and no reported surface rupture, occurred about 95 km southeast of the proposed repository.

  8. High-resolution spectroscopy and analysis of the ν1/ν3 stretching dyad of osmium tetroxide

    NASA Astrophysics Data System (ADS)

    Louviot, M.; Boudon, V.; Manceron, L.; Roy, P.; Balcon, D.

    2012-01-01

    OsO4 is a heavy tetrahedral molecule that may constitute a benchmark for quantum chemistry calculations. Its favorable spin statistics (due to the zero nuclear spin of oxygen atoms) is such that only A1 and A2 rovibrational levels are allowed, leading to a dense, but quite easily resolved spectrum. Most lines are single ones, instead of complex line clusters as in the case of other heavy spherical-tops like SF6, for instance. It is thus possible to fully assign and fit the spectrum and to obtain precise experimental effective molecular parameters. The strong ν3 stretching fundamental has been studied a long time ago as an isolated band [McDowell RS, Radziemski LJ, Flicker H, Galbraith HW, Kennedy RC, Nereson NG, et al. Journal of Chemical Physics 1978;88:1513-21; Bobin B, Valentin A, Henry L. Journal of Molecular Spectroscopy 1987;122:229-41]. We reinvestigate here this region and perform new assignments and effective Hamiltonian parameter fits for the four main isotopologues (192OsO4, 190OsO4, 189OsO4, 188OsO4), by considering the ν1/ν3 stretching dyad. A new experimental spectrum has been recorded at room temperature, thanks to a Bruker IFS 125 HR interferometer and using a natural abundance OsO4 sample. Assignments and analyses were performed thanks to the SPVIEW and XTDS softwares, respectively [Wenger Ch, Boudon V, Rotger M, Sanzharov M, Champion J-P. Journal of Molecular Spectroscopy 2008;251:102-13]. We provide precise effective Hamiltonian parameters, including band centers and Coriolis interaction parameters. We discuss isotopic shifts and estimate the band centers for the three minor isotopologues (187OsO4, 186OsO4, 184OsO4). The Q branches of the first two of them are clearly identified in the experimental spectrum.

  9. A multicentre study of meticillin-resistant Staphylococcus aureus in acute bacterial skin and skin-structure infections in China: susceptibility to ceftaroline and molecular epidemiology.

    PubMed

    Zhang, Hui; Xiao, Meng; Kong, Fanrong; O'Sullivan, Matthew V N; Mao, Lei-Li; Zhao, Hao-Ran; Zhao, Ying; Wang, He; Xu, Ying-Chun

    2015-04-01

    Ceftaroline is a novel cephalosporin with activity against Gram-positive organisms, including meticillin-resistant Staphylococcus aureus (MRSA). The objective of this study was to investigate the susceptibility to ceftaroline of hospital-associated MRSA (HA-MRSA) isolates causing acute bacterial skin and skin-structure infections (ABSSSIs) in China and to examine their relationship by genotyping. A total of 251 HA-MRSA isolates causing ABSSSIs were collected from a multicentre study involving 56 hospitals in 38 large cities across 26 provinces in mainland China. All isolates were characterised by multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCCmec) typing, spa typing and detection of the Panton-Valentine leukocidin locus (lukS-PV and lukF-PV). Minimum inhibitory concentrations (MICs) of 14 antimicrobial agents, including ceftaroline, were determined by broth microdilution and were interpreted using Clinical and Laboratory Standards Institute breakpoints. The ceftaroline MIC50 and MIC90 values (MICs that inhibit 50% and 90% of the isolates, respectively) were 1 μg/mL and 2 μg/mL, respectively; 33.5% (n=84) of the isolates studied were ceftaroline-non-susceptible, with MICs of 2 μg/mL, but no isolate exhibited ceftaroline resistance (MIC>2 μg/mL). All of the ceftaroline-non-susceptible isolates belonged to the predominant HA-MRSA clones: 95.2% (n=80) from MLST clonal complex 8 (CC8), with the remaining 4.8% (n=4) from CC5. The high rate of non-susceptibility to ceftaroline amongst HA-MRSA causing ABSSSIs in China is concerning. PMID:25649348

  10. South Africa plays down faulty condom scare.

    PubMed

    1999-01-11

    South Africa has one of the highest rates of HIV infection in the world, with 3 million of the country's total population of approximately 40 million estimated to be currently infected with HIV. With 1500 people in South Africa contracting HIV every day, it is projected that more than 25% of the country's population will be infected with HIV by 2010. However, despite the current state of affairs regarding HIV/AIDS in South Africa and the extremely high level of HIV prevalence projected for the future, South Africans don't buy condoms. Free distribution, began in 1992, accounts for 90-95% of all condom use in the country. South Africa's Department of Health distributed more than 140 million free condoms in 1998, although as many as 1 million were defective. In an attempt to quell the resultant public uproar over the distribution of sub-standard condoms, a senior HIV/AIDS specialist with the Department of Health assures the population that from April 1, 1999, South Africa will adhere to the same standards as the World Health Organization, and all procurements will have been batch-by-batch tested. This specialist also stated that only one brand of condom, supplied by a manufacturer in India, was found to be defective and was immediately withdrawn. Assertions that other batches imported from China were also sub-standard were false. The Department of Health plans to sponsor a National Condom Week leading up to Valentine's Day on February 14, 1999, to promote condoms and their correct use. PMID:12294480

  11. Characterization of methicillin-resistant Staphylococcus aureus isolates from food and food products of poultry origin in Germany.

    PubMed

    Fessler, Andrea T; Kadlec, Kristina; Hassel, Melanie; Hauschild, Tomasz; Eidam, Christopher; Ehricht, Ralf; Monecke, Stefan; Schwarz, Stefan

    2011-10-01

    During a survey of fresh chicken and turkey meat as well as chicken and turkey meat products for the presence of methicillin-resistant Staphylococcus aureus (MRSA) isolates in Germany, 32 (37.2%) of 86 samples were MRSA positive. Twenty-eight of these MRSA isolates belonged to clonal complex 398 (CC398), which is widespread among food-producing animals. These CC398 isolates carried SCCmec elements of type IV or V and exhibited spa type t011, t034, t899, t2346 or t6574 and either the known dru types dt2b, dt6j, dt10a, dt10q, dt11a, dt11v, and dt11ab or the novel dru types dt6m, dt10as, and dt10at. In addition, two MRSA sequence type 9 (ST9) isolates with a type IV SCCmec cassette, spa type t1430, and dru type dt10a as well as single MRSA ST5 and ST1791 isolates with a type III SCCmec cassette, spa type t002, and dru type dt9v were identified. All but two isolates were classified as multiresistant. A wide variety of resistance phenotypes and genotypes were detected. All isolates were negative for the major virulence factors, such as Panton-Valentine leukocidin, toxic shock syndrome toxin 1, or exfoliative toxins. In contrast to the MRSA CC398 isolates, the four ST9, ST5, or ST1791 isolates harbored the egc gene cluster for enterotoxin G, I, M, N, O, and U genes. Although the relevance of contamination of fresh poultry meat or poultry products with MRSA is currently unclear, the presence of multiresistant and, in part, enterotoxigenic MRSA emphasizes the need for further studies to elucidate possible health hazards for consumers. PMID:21724898

  12. Seismicity of west Texas

    SciTech Connect

    Dumas, D.B.

    1981-01-01

    A four year seismic study has found the Basin and Range province of west Texas and the adjacent area of Mexico to be more seismically active then than heretofore known. A University of Texas five station seismic array around the Marfa Basin has located or detected approximately 800 local and regional earthquakes with S-P times of less than 30 sec. A crustal model for the Basin and Range is derived from natural and artificial sources and contains four layers having velocities of 3.60, 4.93, 6.11, and 6.60 km/sec, respectively, overlying a mantle of 8.37 km/sec. A moderate level of seismic activity has been detected near Van Horn, in the Marfa Basin, and along the Texas-Mexico border between latitudes 30 and 31/sup 0/N. Five earthquake sequences were recorded, two near the Texas-Mexico border and three in the Marfa Basin. Four of these sequences showed quiescent periods in foreshock activity preceding the main shock. On the eastern side of the Marfa Basin a diffuse linear seismic zone may represent an unmapped fault, striking N 50/sup 0/W that coincides with Muehlberger's proposed eastern boundary of Basin and Range faulting. A new epicenter for the Valentine, Texas earthquake of August 16, 1931 has been relocated instrumentally at the northern end of this diffuse zone. Regional and local teleseismic P-wave arrival time anomalies observed for the nearby Gnome underground nuclear explosion of 1961 are used to determine station corrections and thus to locate the new 1931 epicenter at 3.69/sup 0/N, 104.57/sup 0/W. Several estimates of magnitude (m/sub b/) based on intensity data range from 5.6 to 6.4. Fault-plane and composite fault-plane solutions support Muehlberger's hypothesis that the Basin and Range is undergoing extension in a SW-NE direction.

  13. CALL FOR PAPERS: Photorefractive Materials and Effects for Photonics

    NASA Astrophysics Data System (ADS)

    2003-01-01

    Guest editors: Professor Valentin Vlad National Institute for Laser, Plasma and Radiation Physics, Bucharest, Romania Professor Eugenio Fazio Università di Roma `La Sapienza', Italy Professor Mike Damzen Imperial College, London, UK A topical issue of Journal of Optics A: Pure and Applied Optics will be devoted to papers reporting new results in the field of photorefractive effects and their applications in photonics. The topics to be covered will include, but are not limited to: bulletnew photorefractive materials (fast, sensitive in IR) bulletwave mixing in photorefractives bulletphotorefractive phase conjugators bulletholographic storage in photorefractive materials bulletphotorefractive spatial solitons bulletadaptive interconnection with photorefractive devices bulletphase conjugate interferometry bulletoptical analogue and digital computing (including optical correlators) bulletother applications and devices using photorefractive effects. The topical issue is scheduled for publication in November 2003. All papers will be peer reviewed and the normal refereeing standards of Journal of Optics A: Pure and Applied Optics will be maintained. Manuscripts should be prepared according to the general guidelines for authors published in the journal. Full details on how to structure an article, including specific information on figures, tables and references, are available from our Web site at www.iop.org/journals/authors/jopa. There are no page charges. In addition to the usual 25 free offprints, the contributing author of each paper published will receive a complimentary copy of the topical issue. Manuscripts should be submitted to the Publisher by 1 May 2003, although authors are strongly encouraged to submit their work as soon as possible. Please include a covering letter stating that the submission is intended for the Photorefractive Materials and Effects for Photonics special issue, to avoid treatment as a regular submission. Submission address: Dr Claire Blay

  14. High prevalence of methicillin resistance and PVL genes amongStaphylococcus aureus isolates from the nares and skin lesions of pediatric patients with atopic dermatitis

    PubMed Central

    Cavalcante, F.S.; Abad, E.D.; Lyra, Y.C.; Saintive, S.B.; Ribeiro, M.; Ferreira, D.C.; dos Santos, K.R.N.

    2015-01-01

    Staphylococcus aureus is highly prevalent among patients with atopic dermatitis (AD), and this pathogen may trigger and aggravate AD lesions. The aim of this study was to determine the prevalence of S. aureus in the nares of pediatric subjects and verify the phenotypic and molecular characteristics of the isolates in pediatric patients with AD. Isolates were tested for antimicrobial susceptibility, SCCmectyping, and Panton-Valentine Leukocidin (PVL) genes. Lineages were determined by pulsed-field gel electrophoresis and multilocus sequence typing (MLST). AD severity was assessed with the Scoring Atopic Dermatitis (SCORAD) index. Among 106 patients, 90 (85%) presented S. aureus isolates in their nares, and 8 also presented the pathogen in their skin infections. Two patients had two positive lesions, making a total of 10 S. aureusisolates from skin infections. Methicillin-resistant S. aureus(MRSA) was detected in 24 (26.6%) patients, and PVL genes were identified in 21 (23.3%), including 6 (75%) of the 8 patients with skin lesions but mainly in patients with severe and moderate SCORAD values (P=0.0095). All 24 MRSA isolates were susceptible to trimethoprim/sulfamethoxazole, while 8 isolates had a minimum inhibitory concentration (MIC) to mupirocin >1024 μg/mL. High lineage diversity was found among the isolates including USA1100/ST30, USA400/ST1, USA800/ST5, ST83, ST188, ST718, ST1635, and ST2791. There was a high prevalence of MRSA and PVL genes among the isolates recovered in this study. PVL genes were found mostly among patients with severe and moderate SCORAD values. These findings can help clinicians improve the therapies and strategies for the management of pediatric patients with AD. PMID:25992644

  15. Neutrophil depletion causes a fatal defect in murine pulmonary Staphylococcus aureus clearance

    PubMed Central

    Robertson, Charles M.; Perrone, Erin E; McConnell, Kevin W.; Dunne, W. Michael; Boody, Barrett; Brahmbhatt, Tejal; Diacovo, M. Julia; Van Rooijen, Nico; Hogue, Lisa A.; Cannon, Carolyn L.; Buchman, Timothy G.; Hotchkiss, Richard S.; Coopersmith, Craig M.

    2008-01-01

    Background Staphylococcus aureus is the most common cause of healthcare-associated pneumonia. Despite the significant morbidity and mortality associated with the disease, animal models of S. aureus pneumonia are rare. Materials and Methods We examined the pathogenicity of four different strains of S. aureus (both methicillin-sensitive and resistant as well as Panton-Valentine leukocidin positive and negative) in four strains of immunocompetent inbred and outbred mice (FVB/N, C57Bl/6, Balb/c, ND4, n=148). The immunologic basis for the development of murine S. aureus pneumonia was then determined by selectively depleting neutrophils, lymphocytes, or pulmonary macrophages prior to the onset of infection. An additional cohort of animals was rendered immunosuppressed by induction of abdominal sepsis via cecal ligation and puncture 2, 4 or 7 days prior to the onset of pneumonia. Results Nearly all immunocompetent mice survived, regardless of which strain of S. aureus was used or which strain of mouse was infected. Among animals with immune depletion or prior immunosuppression, survival was decreased only following neutrophil depletion (26% vs. 90% alive at 7 days, p<0.0001). Compared to immunocompetent animals, neutrophil-depleted mice with S. aureus pneumonia had delayed pulmonary bacterial clearance at 16 and 40 hours but had no difference in levels of bacteremia. Neutrophil-depleted mice also had elevated levels of pulmonary MCP-1 (822 pg/ml vs. 150 pg/ml, p<0.05). In contrast, pulmonary histologic appearance was similar in both groups as was dry/wet lung weight. Conclusions These results suggest that neutrophils play a critical role in the host response to S. aureus pneumonia, and the survival differences observed in neutrophil-depleted mice are associated with alterations in bacterial clearance and pulmonary cytokine response. PMID:18621398

  16. Methicillin-Resistant Staphylococcus aureus (MRSA) Detected at Four U.S. Wastewater Treatment Plants

    PubMed Central

    Goldstein, Rachel E. Rosenberg; Micallef, Shirley A.; Gibbs, Shawn G.; Davis, Johnnie A.; He, Xin; George, Ashish; Kleinfelter, Lara M.; Schreiber, Nicole A.; Mukherjee, Sampa; Joseph, Sam W.

    2012-01-01

    Background: The incidence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections is increasing in the United States, and it is possible that municipal wastewater could be a reservoir of this microorganism. To date, no U.S. studies have evaluated the occurrence of MRSA in wastewater. Objective: We examined the occurrence of MRSA and methicillin-susceptible S. aureus (MSSA) at U.S. wastewater treatment plants. Methods: We collected wastewater samples from two Mid-Atlantic and two Midwest wastewater treatment plants between October 2009 and October 2010. Samples were analyzed for MRSA and MSSA using membrane filtration. Isolates were confirmed using biochemical tests and PCR (polymerase chain reaction). Antimicrobial susceptibility testing was performed by Sensititre® microbroth dilution. Staphylococcal cassette chromosome mec (SCCmec) typing, Panton-Valentine leucocidin (PVL) screening, and pulsed field gel electrophoresis (PFGE) were performed to further characterize the strains. Data were analyzed by two-sample proportion tests and analysis of variance. Results: We detected MRSA (n = 240) and MSSA (n = 119) in 22 of 44 (50%) and 24 of 44 (55%) wastewater samples, respectively. The odds of samples being MRSA-positive decreased as treatment progressed: 10 of 12 (83%) influent samples were MRSA-positive, while only one of 12 (8%) effluent samples was MRSA-positive. Ninety-three percent and 29% of unique MRSA and MSSA isolates, respectively, were multidrug resistant. SCCmec types II and IV, the pvl gene, and USA types 100, 300, and 700 (PFGE strain types commonly found in the United States) were identified among the MRSA isolates. Conclusions: Our findings raise potential public health concerns for wastewater treatment plant workers and individuals exposed to reclaimed wastewater. Because of increasing use of reclaimed wastewater, further study is needed to evaluate the risk of exposure to antibiotic-resistant bacteria in treated

  17. Antimicrobial susceptibility of Staphylococcus aureus and characterization of methicillin-resistant Staphylococcus aureus isolated from bovine mastitis in Korea.

    PubMed

    Nam, Hyang-Mi; Lee, Ae-Li; Jung, Suk-Chan; Kim, Mal-Nam; Jang, Geum-Chan; Wee, Sung-Hwan; Lim, Suk-Kyung

    2011-02-01

    A total of 402 Staphylococcus aureus isolates from bovine mastitis milk collected during 2003-2009 in Korea were tested for susceptibility to 20 antimicrobial agents. All S. aureus isolates were susceptible to 11 of 20 antimicrobials tested; no resistance was observed against pirlimycin, telithromycin, novobiocin, penicillin/novobiocin, quinupristin/dalfopristin, clindamycin, rifampin, ciprofloxacin, trimethprim/sulfamethoxazol, vancomycin, and linezolid. Over 66% of the S. aureus isolates were resistant to penicillin. Resistance was also seen for gentamicin (11.9%), erythromycin (7.7%), methicillin (oxacillin and cefoxitin, 6.2%), and tetracycline (4.2%). No noticeable change was observed in penicillin, gentamicin, and erythromycin resistance over the 7-year period. Tetracycline resistance appeared to decrease consistently, whereas methicillin resistance was observed from 2005. About 2.7% (11/402) were resistant to three or more antimicrobials. Genotyping of the 17 methicillin-resistant S. aureus (MRSA) isolated from each cow revealed two staphylococcal cassette chromosome mec (SCCmec) types (IV and IVa), three spa types (t286, t324, and untypable), and two sequence types (ST1 and ST72). Eleven of 17 (64.7%) MRSA strains belonged to SCCmec IVa-t324-ST72. The rest of strains belonged to SCCmec IVa-t286-ST1 (n = 3) and SCCmec IV-untypable-ST72 (n = 3). None of the MRSA carried the Panton-Valentine leukocidin gene. These characteristics are the same as those found in community-acquired (CA) MRSA strains prevalent in humans in Korea. Three pulsed-field gel electrophoresis types (A-C) were observed among the 17 MRSA strains examined, and 14 strains belonged to the same pulsed-field gel electrophoresis pattern regardless of their geographical origin and year of isolation. The results of this study provide evidence of CA-MRSA infection in dairy cattle for the first time in Korea. PMID:21034263

  18. Antimicrobial susceptibility of canine and human Staphylococcus aureus collected in Saskatoon, Canada.

    PubMed

    Rubin, J E; Chirino-Trejo, M

    2011-11-01

    Staphylococcus aureus is one of the most common causes of infection in people and is increasingly recognized in dogs. The increasing prevalence of methicillin resistant S. aureus (MRSA) is complicating the treatment of these infections. Panton Valentine leukocidin (PVL), a toxin involved in the pathogenesis of necrotic syndromes in people may be partially responsible for the rise of MRSA. Canine and human S. aureus from the same geographic area are genetically similar, indicating a common population and likely transmission. The implications of increasing antimicrobial resistance complicated by interspecies transmission, necessitates including both dogs and humans in S. aureus resistance surveillance studies. A collection of 126 S. aureus isolates from people (n = 99) and dogs (n = 27) were included, minimum inhibitor concentrations to a panel of 33 antimicrobials used in human and veterinary medicine were determined. No resistance to vancomycin, linezolid, daptomycin, quinupristin/dalfopristin or nitrofurantoin was found. A wide range of antibiograms were found; including resistance to 0-12 drugs (0-6 drug classes). Outstanding antibiograms included a canine MRSA resistant to rifampin and a human MRSA resistant to chloramphenicol. Inducible clindamycin resistance was found among 78% and 4% of canine and human MRSA and 17% and 25% of canine colonizing and human methicillin susceptible S. aureus (MSSA), respectively. Resistance to mupirocin was only found among human isolates including 20% of MRSA and 4% of MSSA. While no canine isolates were PVL positive, 39% of human MRSA and 2% of MSSA carried the gene. The bidirectional transmission of S. aureus between people and dogs necessitates the inclusion of isolates from both species in future studies. PMID:21824346

  19. Origin and Evolution of European Community-Acquired Methicillin-Resistant Staphylococcus aureus

    PubMed Central

    Wirth, Thierry; Andersen, Paal S.; Skov, Robert L.; De Grassi, Anna; Simões, Patricia Martins; Tristan, Anne; Petersen, Andreas; Aziz, Maliha; Kiil, Kristoffer; Cirković, Ivana; Udo, Edet E.; del Campo, Rosa; Vuopio-Varkila, Jaana; Ahmad, Norazah; Tokajian, Sima; Peters, Georg; Schaumburg, Frieder; Olsson-Liljequist, Barbro; Givskov, Michael; Driebe, Elizabeth E.; Vigh, Henrik E.; Shittu, Adebayo; Ramdani-Bougessa, Nadjia; Rasigade, Jean-Philippe; Price, Lance B.; Vandenesch, Francois; Larsen, Anders R.; Laurent, Frederic

    2014-01-01

    ABSTRACT Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) was recognized in Europe and worldwide in the late 1990s. Within a decade, several genetically and geographically distinct CA-MRSA lineages carrying the small SCCmec type IV and V genetic elements and the Panton-Valentine leukocidin (PVL) emerged around the world. In Europe, the predominant CA-MRSA strain belongs to clonal complex 80 (CC80) and is resistant to kanamycin/amikacin and fusidic acid. CC80 was first reported in 1993 but was relatively rare until the late 1990s. It has since been identified throughout North Africa, the Middle East, and Europe, with recent sporadic reports in sub-Saharan Africa. While strongly associated with skin and soft tissue infections, it is rarely found among asymptomatic carriers. Methicillin-sensitive S. aureus (MSSA) CC80 strains are extremely rare except in sub-Saharan Africa. In the current study, we applied whole-genome sequencing to a global collection of both MSSA and MRSA CC80 isolates. Phylogenetic analyses strongly suggest that the European epidemic CA-MRSA lineage is derived from a PVL-positive MSSA ancestor from sub-Saharan Africa. Moreover, the tree topology suggests a single acquisition of both the SCCmec element and a plasmid encoding the fusidic acid resistance determinant. Four canonical SNPs distinguish the derived CA-MRSA lineage and include a nonsynonymous mutation in accessory gene regulator C (agrC). These changes were associated with a star-like expansion into Europe, the Middle East, and North Africa in the early 1990s, including multiple cases of cross-continent imports likely driven by human migrations. PMID:25161186

  20. Changing Epidemiology of Methicillin-Resistant Staphylococcus aureus in Iceland from 2000 to 2008: a Challenge to Current Guidelines ▿ †

    PubMed Central

    Holzknecht, Barbara Juliane; Hardardottir, Hjördis; Haraldsson, Gunnsteinn; Westh, Henrik; Valsdottir, Freyja; Boye, Kit; Karlsson, Sigfus; Kristinsson, Karl Gustaf; Gudlaugsson, Olafur

    2010-01-01

    The epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) is continuously changing. Iceland has a low incidence of MRSA. A “search and destroy” policy (screening patients with defined risk factors and attempting eradication in carriers) has been implemented since 1991. Clinical and microbiological data of all MRSA patients from the years 2000 to 2008 were collected prospectively. Isolates were characterized by pulsed-field gel electrophoresis (PFGE), sequencing of the repeat region of the Staphylococcus protein A gene (spa typing), staphylococcal cassette chromosome mec (SCCmec) typing, and screening for the Panton-Valentine leukocidin (PVL) gene. Two hundred twenty-six infected (60%) or colonized (40%) individuals were detected (annual incidence 2.5 to 16/100,000). From 2000 to 2003, two health care-associated outbreaks dominated (spa types t037 and t2802), which were successfully controlled with extensive infection control measures. After 2004, an increasing number of community-associated (CA) cases without relation to the health care system occurred. A great variety of clones (40 PFGE types and 49 spa types) were found, reflecting an influx of MRSA from abroad. The USA300 and Southwest Pacific (SWP) clones were common. SCCmec type IV was most common (72%), and 38% of the isolates were PVL positive. The incidence of MRSA in Iceland has increased since 1999 but remains low and has been stable in the last years. The search and destroy policy was effective to control MRSA in the health care setting. However, MRSA in Iceland is now shifting into the community, challenging the current Icelandic guidelines, which are tailored to the health care system. PMID:20844224

  1. Trends in Methicillin-Resistant Staphylococcus aureus Anovaginal Colonization in Pregnant Women in 2005 versus 2009▿

    PubMed Central

    Top, Karina A.; Huard, Richard C.; Fox, Zachary; Wu, Fann; Whittier, Susan; Della-Latta, Phyllis; Saiman, Lisa; Ratner, Adam J.

    2010-01-01

    In 2005, the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) anovaginal colonization in pregnant women at our center (Columbia University Medical Center) was 0.5%, and MRSA-colonized women were less likely to carry group B streptococcus (GBS). In this study, our objectives were to identify changing trends in the prevalence of MRSA and methicillin-susceptible S. aureus (MSSA) anovaginal colonization in pregnant women, to assess the association between MRSA and GBS colonization, and to characterize the MRSA strains. From February to July 2009, Lim broths from GBS surveillance samples were cultured for S. aureus. MRSA strains were identified by resistance to cefoxitin and characterized by MicroScan, staphylococcal cassette chromosome mec (SCCmec) typing, pulsed-field gel electrophoresis (PFGE), spa typing, and Panton-Valentine leukocidin PCR. A total of 2,921 specimens from different patients were analyzed. The prevalences of MSSA, MRSA, and GBS colonization were 11.8%, 0.6% and 23.3%, respectively. GBS colonization was associated with S. aureus colonization (odds ratio [OR], 1.9; 95% confidence interval [95% CI], 1.5 to 2.4). The frequencies of GBS colonization were similar in MRSA-positive (34.2%) versus MRSA-negative patients (21.8%) (P = 0.4). All MRSA isolates from 2009 and 13/14 isolates from 2005 were SCCmec type IV or V, consistent with community-associated MRSA; 12/18 (2009) and 0/14 (2005) isolates were the USA300 clone. Levofloxacin resistance increased from 14.3% (2005) to 55.6% (2009) (P = 0.028). In conclusion, the prevalence of MRSA anovaginal colonization in pregnant women in New York City, NY, remained stable from 2005 to 2009, and USA300 emerged as the predominant clone with a significant increase in levofloxacin-resistant isolates. PMID:20686089

  2. Direct, Specific and Rapid Detection of Staphylococcal Proteins and Exotoxins Using a Multiplex Antibody Microarray

    PubMed Central

    Stieber, Bettina; Monecke, Stefan; Müller, Elke; Büchler, Joseph; Ehricht, Ralf

    2015-01-01

    Background S. aureus is a pathogen in humans and animals that harbors a wide variety of virulence factors and resistance genes. This bacterium can cause a wide range of mild to life-threatening diseases. In the latter case, fast diagnostic procedures are important. In routine diagnostic laboratories, several genotypic and phenotypic methods are available to identify S. aureus strains and determine their resistances. However, there is a demand for multiplex routine diagnostic tests to directly detect staphylococcal toxins and proteins. Methods In this study, an antibody microarray based assay was established and validated for the rapid detection of staphylococcal markers and exotoxins. The following targets were included: staphylococcal protein A, penicillin binding protein 2a, alpha- and beta-hemolysins, Panton Valentine leukocidin, toxic shock syndrome toxin, enterotoxins A and B as well as staphylokinase. All were detected simultaneously within a single experiment, starting from a clonal culture on standard media. The detection of bound proteins was performed using a new fluorescence reading device for microarrays. Results 110 reference strains and clinical isolates were analyzed using this assay, with a DNA microarray for genotypic characterization performed in parallel. The results showed a general high concordance of genotypic and phenotypic data. However, genotypic analysis found the hla gene present in all S. aureus isolates but its expression under given conditions depended on the clonal complex affiliation of the actual isolate. Conclusions The multiplex antibody assay described herein allowed a rapid and reliable detection of clinically relevant staphylococcal toxins as well as resistance- and species-specific markers. PMID:26624622

  3. Clinical and Molecular Epidemiology of Methicillin-Resistant Staphylococcus aureus in a Neonatal Intensive Care Unit in the Decade following Implementation of an Active Detection and Isolation Program

    PubMed Central

    Nelson, Melissa U.; Bizzarro, Matthew J.; Baltimore, Robert S.; Dembry, Louise M.

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent source of infection in the neonatal intensive care unit (NICU), often associated with significant morbidity. Active detection and isolation (ADI) programs aim to reduce transmission. We describe a comprehensive analysis of the clinical and molecular epidemiology of MRSA in an NICU between 2003 and 2013, in the decade following the implementation of an MRSA ADI program. Molecular analyses included strain typing by pulsed-field gel electrophoresis, mec and accessory gene regulator group genotyping by multiplex PCR, and identification of toxin and potential virulence factor genes via PCR-based assays. Of 8,387 neonates, 115 (1.4%) had MRSA colonization and/or infection. The MRSA colonization rate declined significantly during the study period from 2.2 to 0.5/1,000 patient days (linear time, P = 0.0003; quadratic time, P = 0.006). There were 19 cases of MRSA infection (16.5%). Few epidemiologic or clinical differences were identified between MRSA-colonized and MRSA-infected infants. Thirty-one different strains of MRSA were identified with a shift from hospital-associated to combined hospital- and community-associated strains over time. Panton-Valentine leukocidin-positive USA300 strains caused 5 of the last 11 infections. Staphylococcal cassette chromosome mec (SCCmec) types II and IVa and agr groups 1 and 2 were most predominant. One isolate possessed the gene for toxic shock syndrome toxin; none had genes for exfoliative toxin A or B. These results highlight recent trends in MRSA colonization and infection and the corresponding changes in molecular epidemiology. Continued vigilance for this invasive pathogen remains critical, and specific attention to the unique host, the neonate, and the distinct environment, the NICU, is imperative. PMID:26019206

  4. Some NACA Muroc personnel with snowman

    NASA Technical Reports Server (NTRS)

    1949-01-01

    The late 1940s saw increased flight activity, and more women computers were needed at the NACA Muroc Flight Test Unit than the ones who had originally arrived in 1946. A call went out to the NACA Langley, Lewis, and Ames laboratories for more women computers. Pictured in this photograph with the Snowman are some of the women computers who responded to the call for help in 1948 along with Roxanah, Emily, Dorothy, who were already here. Standing left to right: Mary (Tut) Hedgepeth, from Langley; Lilly Ann Bajus, Lewis; Roxanah Yancey, Emily Stephens, Jane Collons (Procurement), Leona Corbett (Personnel), Angel Dunn, Langley. Kneeling left to right: Dorothy (Dottie) Crawford Roth, Lewis; Dorothy Clift Hughes, and Gertrude (Trudy) Wilken Valentine, Lewis. In National Advisory Committee for Aeronautics (NACA) terminology of 1946, computers were employees who performed laborious and time-consuming mathematical calculations and data reduction from long strips of records generated by onboard aircraft instrumentation. Virtually without exception, computers were female; at least part of the rationale seems to have been the notion that the work was long and tedious, and men were not thought to have the patience to do it. Though equipment changed over the years and most computers eventually found themselves programming and operating electronic computers, as well as doing other data processing tasks, being a computer initially meant long hours with a slide rule, hunched over illuminated light boxes measuring line traces from grainy and obscure strips of oscillograph film. Computers suffered terrible eyestrain, and those who didn't begin by wearing glasses did so after a few years. But they were initially essential employees at the Muroc Flight Test Unit and NACA High-Speed Flight Research Station, taking the oscillograph flight records and 'reducing' the data on them to make them useful to research engineers, who analyzed the data.

  5. Cortical GABA Levels in Primary Insomnia

    PubMed Central

    Morgan, Peter T.; Pace-Schott, Edward F.; Mason, Graeme F.; Forselius, Erica; Fasula, Madonna; Valentine, Gerald W.; Sanacora, Gerard

    2012-01-01

    Study Objectives: GABA is increasingly recognized as an important neurotransmitter for the initiation and maintenance of sleep. We sought to measure cortical GABA content through proton magnetic resonance spectroscopy (MRS) in persons with and without primary insomnia, and relate brain GABA levels to polysomnographic sleep measures. Design: Two-group comparison study. Setting: Outpatient study at a university research clinic. Participants: Non-medicated persons with primary insomnia (N = 16) and no sleep complaints (N = 17). Interventions: Participants kept sleep diaries and a regular time-in-bed schedule for 9 days, culminating in 2 consecutive nights of ambulatory polysomnography and a single proton MRS session. The main outcome measure was occipital GABA/creatine ratios; secondary measures included sleep measurements and relationship between polysomnographically measured time awake after sleep onset and occipital GABA content. Measurements and Results: The primary insomnia group was distinguished from persons with no sleep complaints on self-reported and polysomnographically measured sleep. The two groups did not differ in age, sex, body mass index, habitual bed- and wake-times, napping, use of caffeine, or use of cigarettes. Mean occipital GABA level was 12% higher in persons with insomnia than in persons without sleep complaints (P < 0.05). In both groups, GABA levels correlated negatively with polysomnographically measured time awake after sleep onset (P < 0.05). Conclusions: Increased GABA levels in persons with insomnia may reflect an allostatic response to chronic hyperarousal. The preserved, negative relationship between GABA and time awake after sleep onset supports this notion, indicating that the possible allostatic response is adaptive. Citation: Morgan PT; Pace-Schott EF; Mason GF; Forselius E; Fasula M; Valentine GW; Sanacora G. Cortical GABA levels in primary insomnia. SLEEP 2012;35(6):807-814. PMID:22654200

  6. Demography and Intercontinental Spread of the USA300 Community-Acquired Methicillin-Resistant Staphylococcus aureus Lineage

    PubMed Central

    Glaser, Philippe; Martins-Simões, Patrícia; Villain, Adrien; Barbier, Maxime; Tristan, Anne; Bouchier, Christiane; Ma, Laurence; Bes, Michele; Laurent, Frederic; Guillemot, Didier; Wirth, Thierry

    2016-01-01

    ABSTRACT Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) was recognized worldwide during the 1990s; in less than a decade, several genetically distinct CA-MRSA lineages carrying Panton-Valentine leukocidin genes have emerged on every continent. Most notably, in the United States, the sequence type 18-IV (ST8-IV) clone known as USA300 has become highly prevalent, outcompeting methicillin-susceptible S. aureus (MSSA) and other MRSA strains in both community and hospital settings. CA-MRSA bacteria are much less prevalent in Europe, where the European ST80-IV European CA-MRSA clone, USA300 CA-MRSA strains, and other lineages, such as ST22-IV, coexist. The question that arises is whether the USA300 CA-MRSA present in Europe (i) was imported once or on very few occasions, followed by a broad geographic spread, anticipating an increased prevalence in the future, or (ii) derived from multiple importations with limited spreading success. In the present study, we applied whole-genome sequencing to a collection of French USA300 CA-MRSA strains responsible for sporadic cases and micro-outbreaks over the past decade and United States ST8 MSSA and MRSA isolates. Genome-wide phylogenetic analysis demonstrated that the population structure of the French isolates is the product of multiple introductions dating back to the onset of the USA300 CA-MRSA clone in North America. Coalescent-based demography of the USA300 lineage shows that a strong expansion occurred during the 1990s concomitant with the acquisition of the arginine catabolic mobile element and antibiotic resistance, followed by a sharp decline initiated around 2008, reminiscent of the rise-and-fall pattern previously observed in the ST80 lineage. A future expansion of the USA300 lineage in Europe is therefore very unlikely. PMID:26884428

  7. Factors Predicting and Reducing Mortality in Patients with Invasive Staphylococcus aureus Disease in a Developing Country

    PubMed Central

    Nickerson, Emma K.; Wuthiekanun, Vanaporn; Wongsuvan, Gumphol; Limmathurosakul, Direk; Srisamang, Pramot; Mahavanakul, Weera; Thaipadungpanit, Janjira; Shah, Krupal R.; Arayawichanont, Arkhom; Amornchai, Premjit; Thanwisai, Aunchalee; Day, Nicholas P.; Peacock, Sharon J.

    2009-01-01

    Background Invasive Staphylococcus aureus infection is increasingly recognised as an important cause of serious sepsis across the developing world, with mortality rates higher than those in the developed world. The factors determining mortality in developing countries have not been identified. Methods A prospective, observational study of invasive S. aureus disease was conducted at a provincial hospital in northeast Thailand over a 1-year period. All-cause and S. aureus-attributable mortality rates were determined, and the relationship was assessed between death and patient characteristics, clinical presentations, antibiotic therapy and resistance, drainage of pus and carriage of genes encoding Panton-Valentine Leukocidin (PVL). Principal Findings A total of 270 patients with invasive S. aureus infection were recruited. The range of clinical manifestations was broad and comparable to that described in developed countries. All-cause and S. aureus-attributable mortality rates were 26% and 20%, respectively. Early antibiotic therapy and drainage of pus were associated with a survival advantage (both p<0.001) on univariate analysis. Patients infected by a PVL gene-positive isolate (122/248 tested, 49%) had a strong survival advantage compared with patients infected by a PVL gene-negative isolate (all-cause mortality 11% versus 39% respectively, p<0.001). Multiple logistic regression analysis using all variables significant on univariate analysis revealed that age, underlying cardiac disease and respiratory infection were risk factors for all-cause and S. aureus-attributable mortality, while one or more abscesses as the presenting clinical feature and procedures for infectious source control were associated with survival. Conclusions Drainage of pus and timely antibiotic therapy are key to the successful management of S. aureus infection in the developing world. Defining the presence of genes encoding PVL provides no practical bedside information and draws attention

  8. Community-acquired methicillin-resistant Staphylococcus aureus in a Malaysian tertiary centre.

    PubMed

    Rashid, Zetti Zainol; Bahari, Norazlah; Othman, Amizah; Jaafar, Roslinda; Mohamed, Nurul Azmawati; Jabbari, Idimaz; Sulong, Anita; Hashim, Rohaidah; Ahmad, Norazah

    2013-01-01

    Abstract. Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is a pathogen recognized to be distinct in both phenotype and genotype from hospital-acquired MRSA. We have identified CA-MRSA cases in Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia, including their antibiotic susceptibility patterns and genotypic characteristics. Cases were identified during January to December 2009 from routine clinical specimens, where culture and antibiotic susceptibility results yielded pauci-resistant MRSA isolates suspected as being CA-MRSA. The patients' clinical data were collected and their specimens were sent for molecular confirmation and analysis. Five cases of CA-MRSA were identified, which had a multi-sensitive pattern on antibiotic susceptibility tests and were resistant to only penicillin and oxacillin. All cases were skin and soft-tissue infections, including diabetic foot with gangrene, infected scalp hematoma, philtrum abscess in a healthcare worker, thrombophlebitis complicated with abscess and infected bedsore. All five cases were confirmed MRSA by detection of mecA. SCCmec typing (ccr and mec complex) revealed SCCmec type IV for all cases except the infected bedsore case. Panton-Valentine leukocidin gene was positive in all isolates. As clinical features among methicillin-sensitive Staphylococcus aureus, CA-MRSA and "nosocomial CA-MRSA" are indistinct, early recognition is necessary in order to initiate appropriate antibiotics and infection control measures. Continual surveillance of pauci-resistant MRSA and molecular analysis are necessary in order to identify emerging strains as well as their epidemiology and transmission, both in the community and in healthcare setting. PMID:23682444

  9. Foods from black market at EU border as a neglected route of potential methicillin-resistant Staphylococcus aureus transmission.

    PubMed

    Oniciuc, Elena-Alexandra; Ariza-Miguel, Jaime; Bolocan, Andrei-Sorin; Diez-Valcarce, Marta; Rovira, Jordi; Hernández, Marta; Fernández-Natal, Isabel; Nicolau, Anca Ioana; Rodríguez-Lázaro, David

    2015-09-16

    The illegal entrance of foods to EU through black markets at the EU borders can constitute a neglected route of dissemination of foodborne pathogens, and in particular of methicillin-resistant Staphylococcus aureus (MRSA). In this study, we have assessed the presence of MRSA in foods sold in a black market at an EU border (the southeast part of Romania, on the border with Republic of Moldavia). We performed a search for MRSA among 200 food samples collected from 2012 to 2013. All S. aureus were studied by pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility testing. MRSA isolates were further characterized by multilocus sequence typing (MLST) and SCCmec typing, and tested for the presence of Panton-Valentine leukocidin (PVL) virulence factors. Overall, 32 S. aureus isolates were recovered from 16 food samples (8%). One isolate detected in a pork lard sample was MRSA (0.5%). PFGE with the restriction enzyme SmaI revealed 12 genotypes among the 32 S. aureus isolates. The MRSA isolate belonged to sequence type 398, harbored SCCmec type V, tested negative for the presence of the PVL genes and was resistant to ciprofloxacin, tetracycline and cefazolin, besides all β-lactams. Among 31 methicillin-sensitive S. aureus (MSSA), 29% were resistant to penicillin, 9.7% to tetracycline and 3.2% to ciprofloxacin. In conclusion, in this study we report the presence of livestock-associated MRSA in foods sold in a black market at an EU border: ST398-MRSA-V. These results confirm the potential role of food in the dissemination of MRSA lineages among population, and the potential role of illegally introduced food to EU in the prevalence and evolution of MRSA clones in the community. PMID:25442069

  10. The Role of Familiarity for Representations in Norm-Based Face Space.

    PubMed

    Faerber, Stella J; Kaufmann, Jürgen M; Leder, Helmut; Martin, Eva Maria; Schweinberger, Stefan R

    2016-01-01

    According to the norm-based version of the multidimensional face space model (nMDFS, Valentine, 1991), any given face and its corresponding anti-face (which deviates from the norm in exactly opposite direction as the original face) should be equidistant to a hypothetical prototype face (norm), such that by definition face and anti-face should bear the same level of perceived typicality. However, it has been argued that familiarity affects perceived typicality and that representations of familiar faces are qualitatively different (e.g., more robust and image-independent) from those for unfamiliar faces. Here we investigated the role of face familiarity for rated typicality, using two frequently used operationalisations of typicality (deviation-based: DEV), and distinctiveness (face in the crowd: FITC) for faces of celebrities and their corresponding anti-faces. We further assessed attractiveness, likeability and trustworthiness ratings of the stimuli, which are potentially related to typicality. For unfamiliar faces and their corresponding anti-faces, in line with the predictions of the nMDFS, our results demonstrate comparable levels of perceived typicality (DEV). In contrast, familiar faces were perceived much less typical than their anti-faces. Furthermore, familiar faces were rated higher than their anti-faces in distinctiveness, attractiveness, likability and trustworthiness. These findings suggest that familiarity strongly affects the distribution of facial representations in norm-based face space. Overall, our study suggests (1) that familiarity needs to be considered in studies of mental representations of faces, and (2) that familiarity, general distance-to-norm and more specific vector directions in face space make different and interactive contributions to different types of facial evaluations. PMID:27168323

  11. Wind Development on Tribal Lands

    SciTech Connect

    Ken Haukaas; Dale Osborn; Belvin Pete

    2008-01-18

    Background: The Rosebud Sioux Tribe (RST) is located in south central South Dakota near the Nebraska border. The nearest community of size is Valentine, Nebraska. The RST is a recipient of several Department of Energy grants, written by Distributed Generation Systems, Inc. (Disgen), for the purposes of assessing the feasibility of its wind resource and subsequently to fund the development of the project. Disgen, as the contracting entity to the RST for this project, has completed all the pre-construction activities, with the exception of the power purchase agreement and interconnection agreement, to commence financing and construction of the project. The focus of this financing is to maximize the economic benefits to the RST while achieving commercially reasonable rates of return and fees for the other parties involved. Each of the development activities required and its status is discussed below. Land Resource: The Owl Feather War Bonnet 30 MW Wind Project is located on RST Tribal Trust Land of approximately 680 acres adjacent to the community of St. Francis, South Dakota. The RST Tribal Council has voted on several occasions for the development of this land for wind energy purposes, as has the District of St. Francis. Actual footprint of wind farm will be approx. 50 acres. Wind Resource Assessment: The wind data has been collected from the site since May 1, 2001 and continues to be collected and analyzed. The latest projections indicate a net capacity factor of 42% at a hub height of 80 meters. The data has been collected utilizing an NRG 9300 Data logger System with instrumentation installed at 30, 40 and 65 meters on an existing KINI radio tower. The long-term annual average wind speed at 65-meters above ground level is 18.2 mph (8.1 mps) and 18.7 mph (8.4 mps) at 80-meters agl. The wind resource is excellent and supports project financing.

  12. Cytoplasmic replication of Staphylococcus aureus upon phagosomal escape triggered by phenol-soluble modulin α.

    PubMed

    Grosz, Magdalena; Kolter, Julia; Paprotka, Kerstin; Winkler, Ann-Cathrin; Schäfer, Daniel; Chatterjee, Som Subra; Geiger, Tobias; Wolz, Christiane; Ohlsen, Knut; Otto, Michael; Rudel, Thomas; Sinha, Bhanu; Fraunholz, Martin

    2014-04-01

    Staphylococcus aureus is a Gram-positive human pathogen that is readily internalized by professional phagocytes such as macrophages and neutrophils but also by non-professional phagocytes such as epithelial or endothelial cells. Intracellular bacteria have been proposed to play a role in evasion of the innate immune system and may also lead to dissemination within migrating phagocytes. Further, S. aureus efficiently lyses host cells with a battery of cytolytic toxins. Recently, phenol-soluble modulins (PSM) have been identified to comprise a genus-specific family of cytolytic peptides. Of these the PSMα peptides have been implicated in killing polymorphonuclear leucocytes after phagocytosis. We questioned if the peptides were active in destroying endosomal membranes to avoid lysosomal killing of the pathogen and monitored integrity of infected host cell endosomes by measuring the acidity of the intracellular bacterial microenvironment via flow cytometry and by a reporter recruitment technique. Isogenic mutants of the methicillin-resistant S. aureus (MRSA) strains USA300 LAC, USA400 MW2 as well as the strongly cytolytic methicillin-sensitive strain 6850 were compared with their respective wild type strains. In all three genetic backgrounds, PSMα mutants were unable to escape from phagosomes in non-professional (293, HeLa, EAhy.926) and professional phagocytes (THP-1), whereas mutants in PSMβ and δ-toxin as well as β-toxin, phosphatidyl inositol-dependent phospholipase C and Panton Valentine leucotoxin escaped with efficiencies of the parental strains. S. aureus replicated intracellularly only in presence of a functional PSMα operon thereby illustrating that bacteria grow in the host cell cytoplasm upon phagosomal escape. PMID:24164701

  13. Cytoplasmic replication of Staphylococcus aureus upon phagosomal escape triggered by phenol-soluble modulin α

    PubMed Central

    Grosz, Magdalena; Kolter, Julia; Paprotka, Kerstin; Winkler, Ann-Cathrin; Schäfer, Daniel; Chatterjee, Som Subra; Geiger, Tobias; Wolz, Christiane; Ohlsen, Knut; Otto, Michael; Rudel, Thomas; Sinha, Bhanu; Fraunholz, Martin

    2013-01-01

    Staphylococcus aureus is a Gram-positive human pathogen that is readily internalized by professional phagocytes such as macrophages and neutrophils but also by non-professional phagocytes such as epithelial or endothelial cells. Intracellular bacteria have been proposed to play a role in evasion of the innate immune system and may also lead to dissemination within migrating phagocytes. Further, S. aureus efficiently lyses host cells with a battery of cytolytic toxins. Recently, phenol-soluble modulins (PSM) have been identified to comprise a genus-specific family of cytolytic peptides. Of these the PSMα peptides have been implicated in killing polymorphonuclear leukocytes after phagocytosis. We questioned if the peptides were active in destroying endosomal membranes to avoid lysosomal killing of the pathogen and monitored integrity of infected host cell endosomes by measuring the acidity of the intracellular bacterial microenvironment via flow cytometry and by a reporter recruitment technique. Isogenic mutants of the methicillin-resistant S. aureus (MRSA) strains USA300 LAC, USA400 MW2 as well as the strongly cytolytic methicillin-sensitive strain 6850 were compared to their respective wild type strains. In all three genetic backgrounds, PSMα mutants were unable to escape from phagosomes in non-professional (293, HeLa, EAhy.926) and professional phagocytes (THP-1), whereas mutants in PSMβ and δ-toxin as well as β-toxin, phosphatidyl inositol-dependent phospholipase C and Panton Valentine leukotoxin escaped with efficiencies of the parental strains. S. aureus replicated intracellularly only in presence of a functional PSMα operon thereby illustrating that bacteria grow in the host cell cytoplasm upon phagosomal escape. PMID:24164701

  14. Interspecies spread of Staphylococcus aureus clones among companion animals and human close contacts in a veterinary teaching hospital. A cross-sectional study in Greece.

    PubMed

    Drougka, Eleanna; Foka, Antigoni; Koutinas, Christos K; Jelastopulu, Eleni; Giormezis, Nikolaos; Farmaki, Ourania; Sarrou, Styliani; Anastassiou, Evangelos D; Petinaki, Efthimia; Spiliopoulou, Iris

    2016-04-01

    Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) prevalence among companion animals and veterinary personnel (VP) was investigated. Strains' molecular characteristics were evaluated in order to assess S. aureus transmission. Specimens (224) from colonized and infected sites of 102 animals (92 dogs, 10 cats) and 18 VP were collected during 2012 and 2013. Antibiotic susceptibility was performed by the disk diffusion method and Etest. mecA, mecC, tst (toxic shock syndrome toxin) and lukF/lukS-PV (Panton-Valentine leukocidin, PVL) genes were investigated by PCR. Genotypes were identified by Multi Locus Sequence Typing (MLST), Staphylococcal Cassette Chromosome mec (SCCmec), accessory gene regulator group (agr), spa and Pulsed Field Gel Electrophoresis (PFGE). S. aureus prevalence among pets and VP was 36.3% (37/102) and 38.9% (7/18), respectively. Younger companion animals, those living in rural areas, having a disease upon admission or Coagulase-negative staphylococci co-carriage showed significantly higher prevalence of S. aureus isolation (p<0.05). Twenty-six pets and five VP carried PVL-positive S. aureus. In total, 60 S. aureus strains were recovered (53 from pets, seven from VP) of which 16 were MRSA (26.7%), 12 mecA- and four mecC-positive. MRSA showed higher resistance rates against other antimicrobials as compared to methicillin-susceptible ones. Strains were classified by MLST in 13 STs, with the predominance of ST80 and ST15. In MRSA, SCCmec types II, IV and XI were identified. The most frequent spa types were t5559 and t7558. Fifty-six strains were classified into 15 PFGE types. Comparison of genetic markers shows that identical or very similar strains disseminate among animals and VP. Companion animals harbor PVL-positive clones constituting a possible source for transmission to humans. PMID:26948298

  15. Genotypic Characterization of Methicillin-Resistant Staphylococcus aureus Recovered at Baseline from Phase 3 Pneumonia Clinical Trials for Ceftobiprole

    PubMed Central

    Deshpande, Lalitagauri M.; Costello, Andrew J.; Farrell, David J.; Jones, Ronald N.; Flamm, Robert K.

    2016-01-01

    Baseline methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients with nosocomial and community-acquired pneumonia collected during Phase 3 trials for ceftobiprole were characterized. Eighty-four unique isolates from patients enrolled in Europe (50.0%), Asia-Western Pacific region (APAC; 20.2%), North America (19.0%), Latin America (8.3%), and South Africa (2.4%) were included. Antimicrobial susceptibility testing was performed by broth microdilution and isolates screened for Panton-Valentine leukocidin. SCCmec and agr types were determined. Strains were subjected to pulsed-field gel electrophoresis and spa typing. Clonal complexes (CCs) were assigned based on spa and/or multilocus sequence typing. Most isolates were CC5-MRSA-I/II/IV (44.0%; 37/84), followed by CC8-MRSA-IV (22.6%; 19/84) and CC239-MRSA-III (21.4%; 18/84). Other MRSA formed seven clonal clusters. Isolates from North America were associated with USA100, while those from South America belonged to the Cordobes/Chilean CC. A greater clonal diversity was observed in Europe; however, each country had CC5, CC8, or CC239 as prevalent lineages. Isolates from APAC were CC5-MRSA-II (47.1%; 8/17) or CC239-MRSA-III (47.1%; 8/17). Isolates carrying SCCmec I and III had ceftobiprole MIC50 values of 2 μg/ml, while those isolates with SCCmec II and IV had MIC50 values of 1 μg/ml. Ceftobiprole inhibited 96% and 100.0% of the isolates at ≤2 and ≤4 μg/ml, respectively. These isolates represented common circulating MRSA clones. Ceftobiprole demonstrated in vitro activity with a slight variation of minimum inhibitory concentrations (MICs) according to SCCmec or clonal type. PMID:26230870

  16. Molecular Characterization and Antimicrobial Susceptibility of Staphylococcus aureus Isolates from Clinical Infection and Asymptomatic Carriers in Southwest Nigeria

    PubMed Central

    Olasupo, Nurudeen A.; Egwari, Louis O.; Becker, Karsten

    2015-01-01

    Few reports from Africa suggest that resistance pattern, virulence factors and genotypes differ between Staphylococcus aureus from nasal carriage and clinical infection. We therefore compared antimicrobial resistance, selected virulence factors and genotypes of S. aureus from nasal carriage and clinical infection in Southwest Nigeria. Non-duplicate S. aureus isolates were obtained from infection (n = 217) and asymptomatic carriers (n = 73) during a cross sectional study in Lagos and Ogun States, Nigeria from 2010–2011. Susceptibility testing was performed using Vitek automated systems. Selected virulence factors were detected by PCR. The population structure was assessed using spa typing. The spa clonal complexes (spa-CC) were deduced using the Based Upon Repeat Pattern algorithm (BURP). Resistance was higher for aminoglycosides in clinical isolates while resistances to quinolones and tetracycline were more prevalent in carrier isolates. The Panton-Valentine leukocidin (PVL) was more frequently detected in isolates from infection compared to carriage (80.2 vs 53.4%; p<0.001, chi2-test). Seven methicillin resistant S. aureus isolates were associated with spa types t002, t008, t064, t194, t8439, t8440 and t8441. The predominant spa types among the methicillin-susceptible S. aureus isolates were t084 (65.5%), t2304 (4.4%) and t8435 (4.1%). spa-CC 084 was predominant among isolates from infection (80.3%, n = 167) and was significantly associated with PVL (OR = 7.1, 95%CI: 3.9–13.2, p<0.001, chi2- test). In conclusion, PVL positive isolates were more frequently detected among isolates from infection compared to carriage and are associated with spa-CC 084. PMID:26348037

  17. Molecular Characterization and Antimicrobial Susceptibility of Staphylococcus aureus Isolates from Clinical Infection and Asymptomatic Carriers in Southwest Nigeria.

    PubMed

    Ayepola, Olayemi O; Olasupo, Nurudeen A; Egwari, Louis O; Becker, Karsten; Schaumburg, Frieder

    2015-01-01

    Few reports from Africa suggest that resistance pattern, virulence factors and genotypes differ between Staphylococcus aureus from nasal carriage and clinical infection. We therefore compared antimicrobial resistance, selected virulence factors and genotypes of S. aureus from nasal carriage and clinical infection in Southwest Nigeria. Non-duplicate S. aureus isolates were obtained from infection (n = 217) and asymptomatic carriers (n = 73) during a cross sectional study in Lagos and Ogun States, Nigeria from 2010-2011. Susceptibility testing was performed using Vitek automated systems. Selected virulence factors were detected by PCR. The population structure was assessed using spa typing. The spa clonal complexes (spa-CC) were deduced using the Based Upon Repeat Pattern algorithm (BURP). Resistance was higher for aminoglycosides in clinical isolates while resistances to quinolones and tetracycline were more prevalent in carrier isolates. The Panton-Valentine leukocidin (PVL) was more frequently detected in isolates from infection compared to carriage (80.2 vs 53.4%; p<0.001, chi2-test). Seven methicillin resistant S. aureus isolates were associated with spa types t002, t008, t064, t194, t8439, t8440 and t8441. The predominant spa types among the methicillin-susceptible S. aureus isolates were t084 (65.5%), t2304 (4.4%) and t8435 (4.1%). spa-CC 084 was predominant among isolates from infection (80.3%, n = 167) and was significantly associated with PVL (OR = 7.1, 95%CI: 3.9-13.2, p<0.001, chi2-test). In conclusion, PVL positive isolates were more frequently detected among isolates from infection compared to carriage and are associated with spa-CC 084. PMID:26348037

  18. High prevalence of hospital-associated methicillin-resistant Staphylococcus aureus in the community in Portugal: evidence for the blurring of community-hospital boundaries.

    PubMed

    Tavares, A; Miragaia, M; Rolo, J; Coelho, C; de Lencastre, H

    2013-10-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of infection in the community (CA-MRSA), but in spite of its relevance, no data exist concerning its epidemiology in Portugal. In this study, we aimed to evaluate the prevalence, population structure, and origin of MRSA in the Portuguese community. A total of 527 isolates, both methicillin-susceptible S. aureus (MSSA) and MRSA, were collected from individuals with no healthcare-related risk factors attending 16 healthcare institutions in Portugal. Isolates were characterized for the presence of mecA, Panton-Valentine leukocidin (PVL), and arginine catabolic mobile element (ACME), and by staphylococcal cassette chromosome mec (SCCmec) typing, pulsed-field gel electrophoresis (PFGE), spa, and multilocus sequence typing (MLST). Susceptibility to a panel of 13 antibiotics was tested. Isolates relatedness was analyzed by goeBURST and BURP. We found a high frequency (21.6%) of MRSA in the community. However, only 11.4% of the isolates belonged to typical CA-MRSA epidemic clones (USA300, USA400, USA700, Southwest Pacific, European, and ST398). The remaining isolates, which constituted the great majority (88.6%), belonged to hospital-associated MRSA (HA-MRSA) epidemic clones, namely, to the EMRSA-15 clone (77.2%). PVL was rare and carried by 17 isolates only (five MRSA and 12 MSSA). In the whole collection, some MRSA and MSSA were highly related. The high frequency of MRSA in the community in Portugal seems to result mainly from dissemination from the hospital. They might also have emerged from an extant MSSA population, by SCCmec acquisition, or MRSA clonal introduction from abroad. PMID:23604782

  19. The greening of the national labs

    SciTech Connect

    Marshall, E.

    1993-04-02

    The big three weapons laboratories - Los Alamos, Livermore, and Sandia - could face dramatic changes in the way they do business if a proposal made by Representative George Brown (D-CA) is enacted. Brown, chairman of the House Science Committee, introduced a bill last week that would consolidate nuclear weapons R D from several labs (without saying at which sites or how). Brown also wants to shift the focus of the labs work more toward civilian projects, and the bill would involve the White House more directly in managing their research agenda. The Brown bill (HR 1432), which has won the backing of Representatives Marilyn Lloyd (D-TN), Tim Valentine (D-NC), Rick Boucher (D-VA), and Ron Wyden (R-OR), asks the secretary of energy to make a comprehensive study of current lab activities and submit a plan to redirect one or more of these labs to civilian missions by 31 March 1994. Brown and other members of Congress had considered turning one of the nuclear weapons centers into a green lab, that is, dedicating it to R D on environmental technology. That idea seems to have been set aside in favor of a more general formula that would be administered by a new Federal Laboratory Mission Evaluation and Coordination Committee, reporting to the president's science adviser. This watchdog panel, according to the bill, would seek to improve the efficiency and effectiveness of all the federal laboratories and ensure that between 10% and 20% of their budgets are devoted to collaborative efforts with industry and state and local governments. Administratively, the bill would also create some new positions at the Dept. of Energy (DOE), including an undersecretary for science and technology who would manage the labs.

  20. Seismicity on the area of the Waste Isolation Pilot Plant (WIPP)

    SciTech Connect

    Sanford, A.; Sanford, S.; Wallace, T.; Barrows, L.; Sheldon, J.; Ward, R.; Johansen, S.; Merritt, L.

    1980-05-01

    Since April 1974, New Mexico Institute of Mining and Technology (NMIMT) has operated a short-period vertical-component seismograph 7 km from the center of the WIPP site. Peak magnifications ranged from 405 K to 1400 K. In the time period from April 1974 to February 1979, approximately 500 earthquakes were recorded by the instrument to distances as great as 660 km. With the aid of readings from stations operated by other organizations, epicenters and magnitudes for 159 earthquakes within about 300 km of the WIPP site were obtained. The greatest concentration of seismic activity is centered on the Central Basin Platform. This zone of activity, approximately 120 km in a NS direction and 100 km in an EW direction, approaches to within 60 km of the site. Other significant clusters of earthquakes occur near Synder, Big Springs and Valentine, Texas. Comparable levels of earthquake activity are observed within 100, 200, and 300 km of the site. Most reported Quaternary faulting lies to the west of 104.3/sup 0/W longitude. Comparable levels of activity were observed to the east and west of this longitude indicating the observed distribution of earthquake activity is probably not representative of the long-term (500,000 years) seismicity of the region. Several lines of evidence suggest that most earthquakes from the Delaware Basin eastward are induced by the production of hydrocarbons, but absolutely convincing proof is lacking. If due to natural tectonic forces, an extrapolation of the observed earthquake-frequency relation indicates an earthquake of magnitude 5 1/2 is possible somewhere within 300 km of the site each 100 years.

  1. CALCULATING SEPARATE MAGNETIC FREE ENERGY ESTIMATES FOR ACTIVE REGIONS PRODUCING MULTIPLE FLARES: NOAA AR11158

    SciTech Connect

    Tarr, Lucas; Longcope, Dana; Millhouse, Margaret

    2013-06-10

    It is well known that photospheric flux emergence is an important process for stressing coronal fields and storing magnetic free energy, which may then be released during a flare. The Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) captured the entire emergence of NOAA AR 11158. This region emerged as two distinct bipoles, possibly connected underneath the photosphere, yet characterized by different photospheric field evolutions and fluxes. The combined active region complex produced 15 GOES C-class, two M-class, and the X2.2 Valentine's Day Flare during the four days after initial emergence on 2011 February 12. The M and X class flares are of particular interest because they are nonhomologous, involving different subregions of the active region. We use a Magnetic Charge Topology together with the Minimum Current Corona model of the coronal field to model field evolution of the complex. Combining this with observations of flare ribbons in the 1600 A channel of the Atmospheric Imaging Assembly on board SDO, we propose a minimization algorithm for estimating the amount of reconnected flux and resulting drop in magnetic free energy during a flare. For the M6.6, M2.2, and X2.2 flares, we find a flux exchange of 4.2 Multiplication-Sign 10{sup 20} Mx, 2.0 Multiplication-Sign 10{sup 20} Mx, and 21.0 Multiplication-Sign 10{sup 20} Mx, respectively, resulting in free energy drops of 3.89 Multiplication-Sign 10{sup 30} erg, 2.62 Multiplication-Sign 10{sup 30} erg, and 1.68 Multiplication-Sign 10{sup 32} erg.

  2. Structural constraints for proposed Fort Hancock low-level radioactive waste disposal site (NTP-S34), southern Hudspeth County, Texas

    SciTech Connect

    Lemone, D.V.

    1989-03-01

    Structural complexities reduce the homogeneity necessary for a site characterization model to an unacceptable level for performance assessment for radioactive waste disposal sites. The proposed site lies between the northern, stable Diablo platform and the southern, mobile Mesozoic Chihuahua tectonic belt. Structural movement along this interface has been active for the past 14,000 years. In addition, the area lies along the northern margin of the Permian Marfa basin and the northeastern margin of the deeply faulted Hueco bolson segment of the late Cenozoic Rio Grande rift system. Recent seismic activity with extensive surface rupture in Quitman Canyon (30 mi southeast of the site) is also documented from the 1931 Valentine, Texas, earthquake (6.4 Richter scale). The site is underlain by either a thrust fault or the complex terminus of a Mesozoic thrust fault. This fault is a segment of the continuous thrust sheet extending from exposures in the Sierra Blanc area, 30 mi east (Devil Ridge fault), to the El Paso area west (Rio Grande fault). This segment of the Devil Ridge-Rio Grande thrust is documented by the Haymond Krupp No. 1 Thaxton wildcat drilled at Campogrande Mountain immediately south of the site. The recent rift fault scarp (Campo Grande) immediately south of the Thaxton well has a 17-mi surface trace and is, no doubt, related to the subsurface Clint fault to the west in the El Paso area. An additional complexity is the presence of a monoclinal flexure with a minimum of 900 ft of surface relief (2 mi northeast of NTP-S34). A 4.5-mi, east-west, down-to-the-south normal fault occurs near the top of the monocline with a small associated graben. These complexities seriously compromise the proposed Fort Hancock site.

  3. Cartographic Production for the FLaSH Map Study: Generation of Rugosity Grids, 2008

    USGS Publications Warehouse

    Robbins, Lisa L.; Knorr, Paul O.; Hansen, Mark

    2010-01-01

    Project Summary This series of raster data is a U.S. Geological Survey (USGS) Data Series release from the Florida Shelf Habitat Project (FLaSH). This disc contains two raster images in Environmental Systems Research Institute, Inc. (ESRI) raster grid format, jpeg image format, and Geo-referenced Tagged Image File Format (GeoTIFF). Data is also provided in non-image ASCII format. Rugosity grids at two resolutions (250 m and 1000 m) were generated for West Florida shelf waters to 250 m using a custom algorithm that follows the methods of Valentine and others (2004). The Methods portion of this document describes the specific steps used to generate the raster images. Rugosity, also referred to as roughness, ruggedness, or the surface-area ratio (Riley and others, 1999; Wilson and others, 2007), is a visual and quantitative measurement of terrain complexity, a common variable in ecological habitat studies. The rugosity of an area can affect biota by influencing habitat, providing shelter from elements, determining the quantity and type of living space, influencing the type and quantity of flora, affecting predator-prey relationships by providing cover and concealment, and, as an expression of vertical relief, can influence local environmental conditions such as temperature and moisture. In the marine environment rugosity can furthermore influence current flow rate and direction, increase the residence time of water in an area through eddying and current deflection, influence local water conditions such as chemistry, turbidity, and temperature, and influence the rate and nature of sedimentary deposition. State-of-the-art computer-mapping techniques and data-processing tools were used to develop shelf-wide raster and vector data layers. Florida Shelf Habitat (FLaSH) Mapping Project (http://coastal.er.usgs.gov/flash) endeavors to locate available data, identify data gaps, synthesize existing information, and expand our understanding of geologic processes in our dynamic

  4. [Helicobacter pylori infection (13C-UBT), and its relationship with nutritional and socioeconomic factors in low income school children from Valencia, Venezuela].

    PubMed

    Páez Valery, M C; Barón, M A; Solano, L; Nadaff, G; Boccio, J; Barrado, A

    2006-12-01

    Helicobacter pylori infection (Hp) is widely spread around the world, and it is considered one of the main causes of chronic gastritis, peptic and duodenal ulcers, and gastric cancer. Recent research has shown that it can be associated with nutritional disorders, mainly with iron and other micronutrient deficiencies. The objective of this study was to assess the prevalence of Hp infection, and infection pattern according to age, sex, nutritional status, and socioeconomic conditions in children who attended the Unidad Educativa "Valentin Espinal" in the city of Valencia. 170 children, between 3 and 14 years of age were studied to assess Hpylori infection (13C-urea breath test), age, nutritional status according to BMI and Height for age, hemoglobin (cianometahemoglobin), serum ferritin (ELISA), socioeconomic status (Graffar-Méndez-Castellano), housing conditions, number of families and of people cohabitating in the same household, and quality of services. 78.8% of the children were infected with Hp, witch was significantly correlated with age but not gender. 25.9% of the sample had undernutrition, and 46.5% were stunted. 98.1% of the families lived in poverty, and 98% of the households showed sanitary deficiencies. A mean of 6.0 +/- 2.4 persons lived in each household (range: 2-15), and an average of 3.2 person shared bedrooms. The odds of being infected were higher in those children who were stunted. Also, socioeconomic status, mother's education level, and poor hosing conditions were significantly associated to being infected. Hpylori is highly prevalent among socially and economically deprived children, and age, overcrowding, and a low education level of the mother increases the risk of being infected. PMID:17425179

  5. Development of a new pentaplex real-time PCR assay for the identification of poly-microbial specimens containing Staphylococcus aureus and other staphylococci, with simultaneous detection of staphylococcal virulence and methicillin resistance markers.

    PubMed

    Okolie, Charles E; Wooldridge, Karl G; Turner, David P; Cockayne, Alan; James, Richard

    2015-06-01

    Staphylococcus aureus strains harbouring genes encoding virulence and antibiotic resistance are of public health importance. In clinical samples, pathogenic S. aureus is often mixed with putatively less pathogenic coagulase-negative staphylococci (CoNS), both of which can harbour mecA, the gene encoding staphylococcal methicillin-resistance. There have been previous attempts at distinguishing MRSA from MRCoNS, most of which were based on the detection of one of the pathognomonic markers of S. aureus, such as coa, nuc or spa. That approach might suffice for discrete colonies and mono-microbial samples; it is inadequate for identification of clinical specimens containing mixtures of S. aureus and CoNS. In the present study, a real-time pentaplex PCR assay has been developed which simultaneously detects markers for bacteria (16S rRNA), coagulase-negative staphylococcus (cns), S. aureus (spa), Panton-Valentine leukocidin (pvl) and methicillin resistance (mecA). Staphylococcal and non-staphylococcal bacterial strains (n = 283) were used to validate the new assay. The applicability of this test to clinical samples was evaluated using spiked blood cultures (n = 43) containing S. aureus and CoNS in mono-microbial and poly-microbial models, which showed that the 5 markers were all detected as expected. Cycling completes within 1 h, delivering 100% specificity, NPV and PPV with a detection limit of 1.0 × 10(1) to 3.0 × 10(1) colony forming units (CFU)/ml, suggesting direct applicability in routine diagnostic microbiology. This is the most multiplexed real-time PCR-based PVL-MRSA assay and the first detection of a unique marker for CoNS without recourse to the conventional elimination approach. There was no evidence that this new assay produced invalid/indeterminate test results. PMID:25790897

  6. Novel characteristics of community-acquired methicillin-resistant Staphylococcus aureus strains belonging to multilocus sequence type 59 in Taiwan.

    PubMed

    Takano, Tomomi; Higuchi, Wataru; Zaraket, Hassan; Otsuka, Taketo; Baranovich, Tatiana; Enany, Shymaa; Saito, Kohei; Isobe, Hirokazu; Dohmae, Soshi; Ozaki, Kyoko; Takano, Misao; Iwao, Yasuhisa; Shibuya, Michiko; Okubo, Takeshi; Yabe, Shizuka; Shi, Da; Reva, Ivan; Teng, Lee-Jene; Yamamoto, Tatsuo

    2008-03-01

    Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) strains, which often produce Panton-Valentine leucocidin (PVL), are increasingly noted worldwide. In this study, we examined 42 MRSA strains (25 PVL-positive [PVL+] strains and 17 PVL-negative [PVL(-)] strains) isolated in Taiwan for their molecular characteristics. The PVL+ MRSA strains included CA-MRSA strains with multilocus sequence type (ST) 59 (major PVL+ MRSA in Taiwan), its variants, and worldwide CA-MRSA ST30 strains. The PVL(-) MRSA strains included the pandemic Hungarian MRSA ST239 strain, the Hungarian MRSA ST239 variant, MRSA ST59 (largely hospital-acquired MRSA strains) and its variants, the pandemic New York/Japan MRSA ST5 strain (Japanese type), and the MRSA ST8 strain. The major PVL+ CA-MRSA ST59 strain possessed a tetracycline resistance-conferring (tetK positive) penicillinase plasmid and a drug resistance gene cluster (a possible composite transposon) for multidrug resistance. Moreover, it carried a novel staphylococcal cassette chromosome mec (SCCmec) with two distinct ccrC genes (ccrC2-C8). This SCCmec (previously named SCCmec type V(T)) was tentatively designated SCCmec type VII. Sequencing of the PVL genes revealed the polymorphisms, and the PVL+ CA-MRSA ST59 strain possessed the ST59-specific PVL gene sequence. The data suggest that a significant amount of clonal spread is occurring in Taiwan and that the major PVL+ CA-MRSA ST59 Taiwan strain exhibits unique genetic characteristics, such as a novel SCCmec type and an ST59-specific PVL gene sequence. PMID:18086843

  7. The emerging ST8 methicillin-resistant Staphylococcus aureus clone in the community in Japan: associated infections, genetic diversity, and comparative genomics.

    PubMed

    Iwao, Yasuhisa; Ishii, Rumiko; Tomita, Yusuke; Shibuya, Yasuhiro; Takano, Tomomi; Hung, Wei-Chun; Higuchi, Wataru; Isobe, Hirokazu; Nishiyama, Akihito; Yano, Mio; Matsumoto, Tetsuya; Ogata, Kikuyo; Okubo, Takeshi; Khokhlova, Olga; Ho, Pak-Leung; Yamamoto, Tatsuo

    2012-04-01

    Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) has become a major concern worldwide. In the United States, ST8 CA-MRSA with SCCmecIVa (USA300) has been predominant, affecting the entire United States. In this study, we investigated Japanese ST8 CA-MRSA with new SCCmecIVl (designated ST8 CA-MRSA/J), which has emerged in Japan since 2003. Regarding community spread and infections, ST8 CA-MRSA/J spread in 16.2-34.4% as a major genotype in the community in Japan, and was associated with skin and soft tissue infections (SSTIs), colitis, and invasive infections (sepsis, epidural abscesses, and necrotizing pneumonia), including influenza prodrome cases and athlete infections, similar to USA300. It spread to even public transport and Hong Kong through a Japanese family. Regarding genetic diversity, ST8 CA-MRSA/J included ST and spa variants and was classified into at least three pulsed-field gel electrophoresis types, ST8 Jα to γ. Of those, ST8 Jβ was associated with severe invasive infections. As for genomics, ST8 CA-MRSA/J showed high similarities to USA300, but with marked diversity in accessory genes; e.g., ST8 CA-MRSA/J possessed enhanced cytolytic peptide genes of CA-MRSA, but lacked the Panton-Valentine leukocidin phage and arginine catabolic mobile element, unlike USA300. The unique features of ST8 CA-MRSA/J included a novel mosaic SaPI (designated SaPIj50) carrying the toxic shock syndrome toxin-1 gene with high expression; the evolution included salvage (through recombination) of hospital-acquired MRSA virulence. The data suggest that ST8 CA-MRSA/J has become a successful native clone in Japan, in association with not only SSTIs but also severe invasive infections (posing a threat), requiring attention. PMID:22350401

  8. Molecular characterization and susceptibility of methicillin-resistant and methicillin-susceptible Staphylococcus aureus isolates from hospitals and the community in Vladivostok, Russia.

    PubMed

    Baranovich, T; Zaraket, H; Shabana, I I; Nevzorova, V; Turcutyuicov, V; Suzuki, H

    2010-06-01

    A prospective study was conducted during an 8-month period, from August 2006 to April 2007, to describe the epidemiology of Staphylococcus aureus-associated infections. In addition, the molecular characteristics, antimicrobial susceptibilities and antibiotic resistance determinants were identified in S. aureus isolates from hospitals and the community in Vladivostok, Russia. Among the 63 S. aureus isolates eligible for this study, methicillin resistance was observed in 48% (n = 30). Hospital-acquired strains accounted for 93% (28/30) of all methicillin-resistant S. aureus (MRSA) isolates. The major MRSA clone (sequence type (ST) 239, staphylococcal cassette chromosome mec (SCCmec) type III, Panton-Valentine leukocidin (PVL)-negative, with two related staphylococcal protein A gene (spa) types (types 3 and 351)) represented 90% of all of the MRSA isolates. This clone was multidrug-resistant, and 41% of isolates showed resistance to rifampicin. Community-acquired MRSA isolates (n = 2) were categorized as ST30, SCCmecIV, spa type 19, and PVL-positive, and as ST8, SCCmecIV, of a novel spa type 826, and PVL-negative. Eight different STs were detected among methicillin-susceptible S. aureus (MSSA) isolates, of which 55% were PVL-positive. One MSSA clone, which was categorized as ST121, spa type 273, and PVL-positive, caused fatal community-acquired pneumonia infections. The strains predominantly isolated in hospitals in Russia belonged to the multidrug-resistant Brazilian/Hungarian ST239 MRSA clone; however, this clone has new antibiotic susceptibilities. Additionally, the emergence of PVL-positive MSSA strains with enhanced virulence was observed, warranting continued surveillance. PMID:19681959

  9. Simulated Antibiotic Exposures in an In Vitro Hollow-Fiber Infection Model Influence Toxin Gene Expression and Production in Community-Associated Methicillin-Resistant Staphylococcus aureus Strain MW2

    PubMed Central

    Pichereau, Solen; Pantrangi, Madhulatha; Couet, William; Badiou, Cedric; Lina, Gerard; Shukla, Sanjay K.

    2012-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strain MW2 harbors a plethora of toxins to mediate its virulence. However, toxin expression and regulation with simulated clinical antimicrobial exposures are unclear. This study evaluated these relationships using an in vitro pharmacodynamic hollow-fiber infection model. Clinical doses of clindamycin, linezolid, minocycline, trimethoprim-sulfamethoxazole (SXT), and vancomycin were simulated over 72 h against MW2 in the hollow fiber model. Expression levels of lukSF-PV and enterotoxin genes sec4, sek, seq, and sel2 were quantified by real-time PCR. Panton-Valentine leukocidin (PVL) was quantified by enzyme-linked immunosorbent assay (ELISA), and cytotoxicity was determined on polymorphonuclear cells (PMNs). Vancomycin produced the maximum MW2 killing (2.53 log10 CFU/ml) after the first dose, but the greatest sustained killing over 72 h occurred with linezolid and clindamycin. Vancomycin and minocycline induced gene upregulation from 0 to 8 h, followed by downregulation for the remaining simulation period. Clindamycin decreased gene expression in the first 24 h, followed by moderate increases (2.5-fold) thereafter. Linezolid increased gene expression 11.4- to 200.4-fold but inhibited PVL production (0.6 ± 0.3 versus 5.9 ± 0.2 μg/ml, linezolid versus control at 72 h; P < 0.05). Similar effects on PVL production occurred with clindamycin and minocycline. SXT increased PVL production at 48 h (2.8-fold) and 72 h (4.9-fold) of treatment (P < 0.05), resulting in increased PVL cytotoxicity on PMNs. Linezolid, clindamycin, and minocycline were the most effective agents on decreasing the virulence potential in CA-MRSA, notably after 8 h of treatment. SXT had minimal effects on toxin gene regulation, but it increased production and cytotoxicity of PVL toxin in the model and may enhance virulence when it is used to treat severe infections. PMID:22064533

  10. Optimisation explains global leaf trait patterns and plant adaptations to global change (Invited)

    NASA Astrophysics Data System (ADS)

    Dewar, R. C.; McMurtrie, R. E.

    2009-12-01

    Measured values of four key leaf traits (leaf area per unit mass, nitrogen concentration, photosynthetic rate and leaf lifespan) co-vary globally according to relationships that hold across all the world’s terrestrial plants. The same leaf traits respond consistently to altered environmental conditions (e.g. light intensity, carbon dioxide concentration and nitrogen supply). Explaining observed global leaf trait patterns and leaf responses to environmental change is a prerequisite to understanding and predicting vegetation responses to global change more generally across a range of time scales. Recently [1] we have shown, using a simple model of plant carbon-nitrogen economy, that all of these leaf trait patterns and responses are consistent with an optimisation hypothesis that cumulative carbon export from leaves over their lifespan is maximised. Various closely-related optimisation hypotheses also explain other plant adaptations to environmental change, such as stomatal responses and altered patterns of growth allocation [2]. Incorporating plant optimisation into large scale vegetation-atmosphere models would ensure they are consistent with global leaf trait relationships, and would improve predictions of vegetation responses to global change. The challenge, both scientific and operational, is to do this consistently over a wide range of time scales. This talk will review our recent work using plant optimisation models [1,2] and highlight the potential of Maximum Entropy Production as a unifying optimisation principle for plant and ecosystem function across different time scales [3]. [1] McMurtrie RE, Dewar RC. 2009. Global variation of leaf traits explained from an hypothesis of optimal plant function. Manuscript in preparation. [2] Dewar RC, Franklin O, Makela A, McMurtrie RE, Valentine HT. 2009. Optimal function explains forest responses to global change. BioScience 59:127-139. [3] Dewar RC. 2009. Maximum entropy production and plants. Submitted to Phil

  11. Five birds, one stone: neutralization of α-hemolysin and 4 bi-component leukocidins of Staphylococcus aureus with a single human monoclonal antibody.

    PubMed

    Rouha, Harald; Badarau, Adriana; Visram, Zehra C; Battles, Michael B; Prinz, Bianka; Magyarics, Zoltán; Nagy, Gábor; Mirkina, Irina; Stulik, Lukas; Zerbs, Manuel; Jägerhofer, Michaela; Maierhofer, Barbara; Teubenbacher, Astrid; Dolezilkova, Ivana; Gross, Karin; Banerjee, Srijib; Zauner, Gerhild; Malafa, Stefan; Zmajkovic, Jakub; Maier, Sabine; Mabry, Robert; Krauland, Eric; Wittrup, K Dane; Gerngross, Tillman U; Nagy, Eszter

    2015-01-01

    Staphylococcus aureus is a major human pathogen associated with high mortality. The emergence of antibiotic resistance and the inability of antibiotics to counteract bacterial cytotoxins involved in the pathogenesis of S. aureus call for novel therapeutic approaches, such as passive immunization with monoclonal antibodies (mAbs). The complexity of staphylococcal pathogenesis and past failures with single mAb products represent considerable barriers for antibody-based therapeutics. Over the past few years, efforts have focused on neutralizing α-hemolysin. Recent findings suggest that the concerted actions of several cytotoxins, including the bi-component leukocidins play important roles in staphylococcal pathogenesis. Therefore, we aimed to isolate mAbs that bind to multiple cytolysins by employing high diversity human IgG1 libraries presented on the surface of yeast cells. Here we describe cross-reactive antibodies with picomolar affinity for α-hemolysin and 4 different bi-component leukocidins that share only ∼26% overall amino acid sequence identity. The molecular basis of cross-reactivity is the recognition of a conformational epitope shared by α-hemolysin and F-components of gamma-hemolysin (HlgAB and HlgCB), LukED and LukSF (Panton-Valentine Leukocidin). The amino acids predicted to form the epitope are conserved and known to be important for cytotoxic activity. We found that a single cross-reactive antibody prevented lysis of human phagocytes, epithelial and red blood cells induced by α-hemolysin and leukocidins in vitro, and therefore had superior effectiveness compared to α-hemolysin specific antibodies to protect from the combined cytolytic effect of secreted S. aureus toxins. Such mAb afforded high levels of protection in murine models of pneumonia and sepsis. PMID:25523282

  12. Staphylococcus aureus Nasal Carriage among Beefpacking Workers in a Midwestern United States Slaughterhouse

    PubMed Central

    Leibler, Jessica H.; Jordan, Jeanne A.; Brownstein, Kirsten; Lander, Lina; Price, Lance B.; Perry, Melissa J.

    2016-01-01

    Occupational contact with livestock is an established risk factor for exposure to livestock-associated methicillin-resistant Staphylococcus aureus (MRSA), particularly among industrial swine workers. While S. aureus is known to infect cattle, livestock-associated S. aureus carriage among workers in the beef production chain has received limited attention. Beefpacking workers, who slaughter, butcher and process cattle, have intensified exposure to potentially infectious animal materials and may be at risk of livestock-associated S. aureus exposure. We conducted a cross-sectional study of beefpacking workers (n = 137) at an industrial slaughterhouse in the Midwestern United States to evaluate prevalence and characteristics of S. aureus nasal colonization, specifically the absence of the scn gene to identify putative association with livestock, antibiotic susceptibility, presence of Panton-Valentin leukocidin (PVL) genes lukS-PV and lukF-PV, and spa type. Overall prevalence of S. aureus nasal carriage was 27.0%. No workers carried livestock-associated MRSA. Methicillin-sensitive S. aureus isolates (MSSA) recovered from five workers (3.6%) lacked the scn gene and were considered putative livestock-associated S. aureus (pLA-SA). Among pLA-SA isolates, spa types t338, t748, t1476 and t2379 were identified. To our knowledge, these spa types have not previously been identified as associated with livestock. Prevalence of human-adapted MRSA carriage in workers was 3.6%. MRSA isolates were identified as spa types t002, t008 and t024, and four of five MRSA isolates were PVL-positive. To date, this is the first study to indicate that industrial beefpacking workers in the United States may be exposed to livestock-associated S. aureus, notably MSSA, and to spa types not previously identified in livestock and livestock workers. Occupational exposure to livestock-associated S. aureus in the beef production chain requires further epidemiologic investigation. PMID:26866374

  13. Drug resistance and genetic characteristics of clinical isolates of staphylococci in Myanmar: high prevalence of PVL among methicillin-susceptible Staphylococcus aureus belonging to various sequence types.

    PubMed

    Aung, M S; Zi, H; Nwe, K M; Maw, W W; Aung, M T; Min, W W; Nyein, N; Kawaguchiya, M; Urushibara, N; Sumi, A; Kobayashi, N

    2016-03-01

    Prevalence, drug resistance and genetic characteristics were analysed for a total of 128 clinical isolates of staphylococci obtained from a tertiary hospital in Myanmar. The dominant species were S. aureus (39%) and S. haemolyticus (35%), followed by S. epidermidis (6%) and S. saprophyticus (5%). The majority of S. haemolyticus isolates (71.1%) harboured mecA, showing high resistance rates to ampicillin, cephalosporins, erythromycin and levofloxacin, while methicillin-resistant S. aureus (MRSA) was only 8% (four isolates) among S. aureus with type IV SCCmec. Panton-Valentine leukocidin (PVL) genes were detected in 20 isolates of S. aureus (40%), among which only one isolate was MRSA belonging to sequence type (ST) 88/agr-III/coa-IIIa, and the other 19 methicillin-susceptible S. aureus (MSSA) isolates were classified into six STs (ST88, ST121, ST1153, ST1155, ST1930, ST3206). An ST1153 MSSA isolate with PVL was revealed to belong to a novel coa type, XIIIa. ST121 S. aureus was the most common in the PVL-positive MSSA (47%, 9/19), harbouring genes of bone sialoprotein and variant of elastin binding protein as a distinctive feature. Although PVL-positive MSSA was susceptible to most of the antimicrobial agents examined, ST1930 isolates were resistant to erythromycin and levofloxacin. ST59 PVL-negative MRSA and MSSA had more resistance genes than other MRSA and PVL-positive MSSA, showing resistance to more antimicrobial agents. This study indicated higher prevalence of mecA associated with multiple drug resistance in S. haemolyticus than in S. aureus, and dissemination of PVL genes to multiple clones of MSSA, with ST121 being dominant, among hospital isolates in Myanmar. PMID:27257489

  14. Molecular characterization of methicillin-resistant Staphylococcus aureus isolated from tertiary care hospitals

    PubMed Central

    Asghar, Atif H.

    2014-01-01

    Background and Objectives: Methicillin-resistant S. aureus (MRSA) tends to be resistant to multiple antibiotics. Methicillin resistance is conferred by the acquisition of the mecA gene, which is carried by a mobile genetic element called the staphylococcal cassette chromosome mec (SCCmec). There are five major types of SCCmec elements (I–V). The majority of hospital-acquired MRSA (HA-MRSA) strains carry SCCmec types I, II, or III, whereas community-acquired MRSA (CA-MRSA) strains carry SCCmec types IV or V. In addition, Panton-Valentine Leucocidin (PVL) is a gene encoding a powerful cytotoxin that is strongly associated with CA-MRSA strains. The present study was aimed to identify the types of SCCmec and PVL genes among clinical MRSA isolates. Methods: This study was conducted in 5 tertiary care hospitals in Makkah city from March to September of 2012. A total of 206 S. aureus clinical isolates were analysed using standard microbiological methods. Multiplex PCR was performed on genomic DNA from MRSA isolates in order to identify the types of SCCmec. In addition, PCR was performed to detect the PVL gene among the isolates. Results: Of the 206 S. aureus isolates, 114 (55.3%) were MRSA, and 100 of the MRSA isolates carried the mecA gene. Results from SCCmec typing revealed that 3% were type I; 9% were type II; 47% were type III, and 29% were type IV. Nineteen per cent of the isolates harboured the PVL gene. Furthermore, there was a statistically significant correlation between the presence of the PVL gene and SCCmec type IV. Conclusion: The virulence of MRSA strains is increasing in both hospital and community settings in Makkah, highlighting the importance of their rapid identification in order to appropriately control infection. PMID:25097499

  15. The use of the Schmidt-hammer for dating paraglacial and glacial landforms in central Austria

    NASA Astrophysics Data System (ADS)

    Rode, M.; Kranabeter, R.; Kellerer-Pirklbauer, A.

    2009-04-01

    The Schmidt-hammer is a portable instrument traditionally used for concrete stability testing by recording a rebound value (R-value) of a spring loaded bolt impacting a surface. This R-value is proportional to the compressive strength of the rock surface and gives a relative measure of the surface hardness. High R-values are indicative of a lower age and low R-values indicate a higher age. In this study, the Schmidt-hammer method was applied at different landforms at two study areas in Austria, at the Schöderkogel-Eisenhut area, Schladminger Mountains (12°02'E, 46°15'N; SA1) and at the Valentin Valley-Eiskar area in the Carnic Alps (12°54'E, 46°37'N; SA2). SA1 is dominated by mica schist whereas SA2 by different types of carbonatic rocks. At SA1, five relict rock glaciers and adjacent landforms (one Lateglacial moraine and deposits of a recent rock fall event) were studied. On each of the five rock glaciers, four to six locations close to the central flow line between the frontal ridge and the rooting zone were measured. At SA2, one rock glacier like landform, one moraine ridge dating from the Little Ice Age (LIA) in front of the Eiskar Glacier, supraglacial deposits of the same glacier and adjacent landforms (one Lateglacial moraine and deposits of a recent rock fall event) were examined. The results at SA1 show comparable results at all five rock glaciers with lowest values at the front and statistically significant higher values at the rooting zone. The difference between the highest and lowest mean R-value at study site 1 is 21.2 (24.4 vs. 45.6.). The differences between the highest and the lowest mean R-value at each of the five rock glaciers are 13.1 at the Gamskar Rock Glacier (28.1 vs. 41.2), 14.1 at the Eisenhut Rock Glacier (26.0 vs. 40.1), 13.6 at the Sulzkogel Rock Glacier (32.0 vs. 45.6), 15.2 at the Breitdach Rock Glacier (26.1 vs. 41.3) and 9.9 at the Schöderkogel Rock Glacier (24.4 vs. 34.3) indicating long formation periods if compared to

  16. Spatial paradigms of lotic diatom distribution: A landscape ecology perspective

    USGS Publications Warehouse

    Passy, S.I.

    2001-01-01

    Spatial distributional patterns of benthic diatoms and their relation to current velocity were investigated in an unshaded cobble-bottom reach of White Creek (Washington County, NY). On 27 August 1999, diatoms were sampled and current velocity and depth were measured on a regular square sampling grid with a grain size of 0.01 m2, interval of 0.5 m, and extent of 16 m2. The relative abundance of the 18 common diatom species enumerated in the 81 samples was subjected to detrended correspondence analysis (DCA). The first axis (DCA1) explained 51% of the variance in diatom data and separated the samples according to current regimes. The spatial autocorrelation of DCA1 sample scores in deposition and erosion regions of White Creek was determined by Moran's I statistic to indicate patch size. In White Creek the patch length of all diatom communities was more than 3.1 m, whereas the patch width was 1 m in the deposition region and 0.5 m in the erosion region. There were 5 dominant diatom taxa, Achnanthes minutissima Ku??tz. et vars, Fragilaria capucina Dezmazie??res et vars, F. crotonensis Kitt., Diatoma vulgaris Bory, and Synedra ulna (Nitz.) Ehr. et vars. The patch length of the dominant species varied from 1 to more than 4.1 m, whereas the patch width, if defined, was 0.5 m. Achnanthes minutissima and F. capucina, the two diatom species with the highest relative abundance, displayed spatially structured patches of low abundance and comparatively random patches of high abundance, suggesting broad scale abiotic control of species performance in low abundance regions and finer scale biotic control of high abundance areas. Another objective of this study was to test the hypothesis that higher current velocities, which generally impede immigration, would increase randomness and complexity (i.e. homogeneity of diatom distributional patterns). The spatial complexity in low versus high velocity transects was determined by calculating the respective fractal dimension (D) of DCA

  17. Einstein's idealism and a new kind of space research

    NASA Astrophysics Data System (ADS)

    Popov, M. A.

    In 1935, Albert Einstein, Boris Podolsky and Nathan Rosen made an attempt to imagine quantum experimental nonsense or some impossible experiment (EPR-experiment) in order to justify their local realism in physics. However, in the mid-1960s, John Bell showed that it is possible to realize this kind of nonsense in laboratory. Today, when EPR-refutation of local realism is routine in modern experimental physics (Clauser and Freedman [1972]; Aspect, Dalibard and Roger [1982]; Zeilinger et al. [1998]), we must; nevertheless, remark that Albert Einstein was not always a realist. As is known, in his Special Relativitz A. Einstein introduced some pure idealistic principle which K. Godel developed in famous "Remark about the relationship between Relativity theorz and Idealistic Philosophy" (1949). Kurt Godel for the first time showed an existence of special-relativistic solipsism, assuming that objective simultaneity in experimental science "loses its objective meaning". Correspondingly, there is only subjective simultaneity, that is provable by calculations with the finite velocity of light and astronomical observations. In particular, this space solipsism means that when we observe the sun, we can see only what happend on Sun 8.33 minutes ago; in other words, we percieve only certain sensations or a certain collections of ideas of the past, but not the present. Similarly, when astronomers observe galaxies estimated to be two billion light years from the Earth, they see these galaxies as they were two billion light years ago not as they are Now. Thus, in accordance with this, we may await that in this context for some pairs of astronomical objects we cannot prove they exist NOW. Moreover, this new kind of space research could be connected with introduction of the Cognitive Dark Matter, or, what is associated with manifold of the large-scale events of the Universe as a whole which are realizing Now, beyond consciousness of the observers-humans. Because we cannot know

  18. Proton polarisability contribution to the Lamb shift in muonic hydrogen at fourth order in chiral perturbation theory

    NASA Astrophysics Data System (ADS)

    McGovern, Judith

    2013-04-01

    The recent determination of the proton charge radius from the Lamb shift in muonic hydrogen [1] gives a value that differs by many standard deviations from the CODATA value [2] and from the results of recent electron scattering experiments [3]. In the theoretical calculations [4], the least-well-determined contribution is the ``proton polarisability'' contribution. This is the part of the two-photon exchange which involves proton excitations. The dominant effect can be determined via dispersion relations from the proton structure functions, but a subtraction term remains [5,6]. This subtraction term is the amplitude T1(0,Q^2) for forward, zero-energy, doubly-virtual Compton scattering, which we calculate in heavy-baryon chiral perturbation theory, to fourth order in the chiral expansion and with the leading contribution of the γNδ form factor. This provides a model-independent expression for the amplitude in the low-momentum region, which is the dominant one for its contribution to the Lamb shift, and allows us to significantly reduce the theoretical uncertainty in the latter [7].[4pt] [1] R. Pohl et al., Nature 466, 213 (2010).[0pt] [2] P. J. Mohr, B. N. Taylor and D. B. Newell, Rev. Mod. Phys. 80, 633 (2008) [arXiv:0801.0028].[0pt] [3] J. C. Bernauer et al. (A1 Collaboration), Phys. Rev. Lett. 105, 242001 (2010) [arXiv:1007.5076].[0pt] [4] U. D. Jentschura, Ann. Phys. 326, 500 (2011) [arXiv:1011.5275]; E. Borie, Ann. Phys. 327, 733 (2012) [arXiv:1103.1772].[0pt] [5] K. Pachucki, Phys. Rev. A 60, 3593 (1999) [arXiv:physics/9906002].[0pt] [6] C. E. Carlson and M. Vanderhaeghen, Phys. Rev. A 84, 020102 (2011) [arXiv:1101.5965]; also [arXiv:1109.3779].[0pt] [7] M. C. Birse and J. A. McGovern, Eur. Phys. J. A48, 120 (2012) [arXiv:1206.3030].

  19. PREFACE: Hot Quarks 2014: Workshop for young scientists on the physics of ultrarelativistic nucleus-nucleus collisions

    NASA Astrophysics Data System (ADS)

    2015-05-01

    ) Boris Hippolyte, CNRS-IN2P3 and Université de Strasbourg (France) Jiangyong Jia, Stony Brook University and Brookhaven National Laboratory (USA) André Mischke, Utrecht University and Nikhef Amsterdam (The Netherlands) Ágnes Mócsy, Pratt Institute and Brookhaven National Laboratory (USA) Hannah Petersen, Goethe University, FIAS and GSI (Germany) Lijuan Ruan, Brookhaven National Laboratory (USA) Sevil Salur, Rutgers University, (USA)

  20. Bauman Moscow State Technical University Youth Space Centre: Student's Way in Space Technologies

    NASA Astrophysics Data System (ADS)

    Mayorova, Victoria; Zelentsov, Victor

    2002-01-01

    The Youth Space Center (YSC) was established in Bauman Moscow State Technical University (BMSTU) in 1989 to provide primary aerospace education for young people, stimulate youth creative research thinking, promote space science and technology achievements and develop cooperation with other youth organizations in the international aerospace community. The center is staffed by the Dr. Victoria Mayorova, BMSTU Associate Professor, the YSC director, Dr. Boris Kovalev, BMSTU Associate Professor, the YSC scientific director, 5 student consultants and many volunteers. Informally YSC is a community of space enthusiasts, an open club for BMSTU students interested in space science and technology and faculty teaching in this field. YSC educational activities are based on the concept of uninterrupted aerospace education, developed and implemented by the center. The concept includes working with young space interested people both in school and university and then assisting them in getting interesting job in Russian Space Industry. The school level educational activities of the center has got different forms, such as lecturing, summer scientific camps and even Classes from Space given by Mir space station flight crew in Mission Control Center - Moscow and done in cooperation with All- Russian Aerospace Society Soyuz (VAKO Soyuz). This helps to stimulate the young people interest to the fundamental sciences ( physics, mathematics, computer science, etc.) exploiting and developing their interest to space and thus increase the overall educational level in the country. YSC hosts annual Cosmonautics conference for high school students that provides the University with capability to select well-prepared and motivated students for its' rocket and space related departments. For the conference participants it's a good opportunity to be enrolled to the University without entrance examinations. BMSTU students can participate in such YSC activities as annual international workshop for space