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Sample records for pneumophila exploits pi4p

  1. The Origin, Dynamic Morphology, and PI4P-Independent Formation of Encephalomyocarditis Virus Replication Organelles

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    C. E. Melia

    2018-04-01

    Full Text Available Picornaviruses induce dramatic rearrangements of endomembranes in the cells that they infect to produce dedicated platforms for viral replication. These structures, termed replication organelles (ROs, have been well characterized for the Enterovirus genus of the Picornaviridae. However, it is unknown whether the diverse RO morphologies associated with enterovirus infection are conserved among other picornaviruses. Here, we use serial electron tomography at different stages of infection to assess the three-dimensional architecture of ROs induced by encephalomyocarditis virus (EMCV, a member of the Cardiovirus genus of the family of picornaviruses that is distantly related. Ultrastructural analyses revealed connections between early single-membrane EMCV ROs and the endoplasmic reticulum (ER, establishing the ER as a likely donor organelle for their formation. These early single-membrane ROs appear to transform into double-membrane vesicles (DMVs as infection progresses. Both single- and double-membrane structures were found to support viral RNA synthesis, and progeny viruses accumulated in close proximity, suggesting a spatial association between RNA synthesis and virus assembly. Further, we explored the role of phosphatidylinositol 4-phosphate (PI4P, a critical host factor for both enterovirus and cardiovirus replication that has been recently found to expedite enterovirus RO formation rather than being strictly required. By exploiting an EMCV escape mutant, we found that low-PI4P conditions could also be overcome for the formation of cardiovirus ROs. Collectively, our data show that despite differences in the membrane source, there are striking similarities in the biogenesis, morphology, and transformation of cardiovirus and enterovirus ROs, which may well extend to other picornaviruses.

  2. Direct interaction of the Golgi V-ATPase a-subunit isoform with PI(4)P drives localization of Golgi V-ATPases in yeast.

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    Banerjee, Subhrajit; Kane, Patricia M

    2017-09-15

    Luminal pH and phosphoinositide content are fundamental features of organelle identity. Vacuolar H + -ATPases (V-ATPases) drive organelle acidification in all eukaryotes, and membrane-bound a-subunit isoforms of the V-ATPase are implicated in organelle-specific targeting and regulation. Earlier work demonstrated that the endolysosomal lipid PI(3,5)P 2 activates V-ATPases containing the vacuolar a-subunit isoform in Saccharomyces cerevisiae Here we demonstrate that PI(4)P, the predominant Golgi phosphatidylinositol (PI) species, directly interacts with the cytosolic amino terminal (NT) domain of the yeast Golgi V-ATPase a-isoform Stv1. Lysine-84 of Stv1NT is essential for interaction with PI(4)P in vitro and in vivo, and interaction with PI(4)P is required for efficient localization of Stv1-containing V-ATPases. The cytosolic NT domain of the human V-ATPase a2 isoform specifically interacts with PI(4)P in vitro, consistent with its Golgi localization and function. We propose that NT domains of V o a-subunit isoforms interact specifically with PI lipids in their organelles of residence. These interactions can transmit organelle-specific targeting or regulation information to V-ATPases. © 2017 Banerjee and Kane. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  3. Hijacking of the Host Ubiquitin Network by Legionella pneumophila

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    Jiazhang Qiu

    2017-12-01

    Full Text Available Protein ubiquitination is critical for regulation of numerous eukaryotic cellular processes such as protein homeostasis, cell cycle progression, immune response, DNA repair, and vesicular trafficking. Ubiquitination often leads to the alteration of protein stability, subcellular localization, or interaction with other proteins. Given the importance of ubiquitination in the regulation of host immunity, it is not surprising that many infectious agents have evolved strategies to interfere with the ubiquitination network with sophisticated mechanisms such as functional mimicry. The facultative intracellular pathogen Legionella pneumophila is the causative agent of Legionnaires' disease. L. pneumophila is phagocytosed by macrophages and is able to replicate within a niche called Legionella-containing vacuole (LCV. The biogenesis of LCV is dependent upon the Dot/Icm type IV secretion system which delivers more than 330 effector proteins into host cytosol. The optimal intracellular replication of L. pneumophila requires the host ubiquitin-proteasome system. Furthermore, membranes of the bacterial phagosome are enriched with ubiquitinated proteins in a way that requires its Dot/Icm type IV secretion system, suggesting the involvement of effectors in the manipulation of the host ubiquitination machinery. Here we summarize recent advances in our understanding of mechanisms exploited by L. pneumophila effector proteins to hijack the host ubiquitination pathway.

  4. Hartmannella vermiformis inhibition of Legionella pneumophila cultivability

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    Hartmannella vermiformis is frequently isolated from drinking water (DW) and is permissive to Legionella pneumophila intracellular replication. Thus, H. vermiformis may play an important role in the growth and survival potential of such environmental pathogens. In this study, Pag...

  5. Invasion of Eukaryotic Cells by Legionella Pneumophila: A Common Strategy for all Hosts?

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    Paul S Hoffman

    1997-01-01

    Full Text Available Legionella pneumophila is an environmental micro-organism capable of producing an acute lobar pneumonia, commonly referred to as Legionnaires’ disease, in susceptible humans. Legionellae are ubiquitous in aquatic environments, where they survive in biofilms or intracellularly in various protozoans. Susceptible humans become infected by breathing aerosols laden with the bacteria. The target cell for human infection is the alveolar macrophage, in which the bacteria abrogate phagolysosomal fusion. The remarkable ability of L pneumophila to infect a wide range of eukaryotic cells suggests a common strategy that exploits very fundamental cellular processes. The bacteria enter host cells via coiling phagocytosis and quickly subvert organelle trafficking events, leading to formation of a replicative phagosome in which the bacteria multiply. Vegetative growth continues for 8 to 10 h, after which the bacteria develop into a short, highly motile form called the ‘mature form’. The mature form exhibits a thickening of the cell wall, stains red with the Gimenez stain, and is between 10 and 100 times more infectious than agar-grown bacteria. Following host cell lysis, the released bacteria infect other host cells, in which the mature form differentiates into a Gimenez-negative vegetative form, and the cycle begins anew. Virulence of L pneumophila is considered to be multifactorial, and there is growing evidence for both stage specific and sequential gene expression. Thus, L pneumophila may be a good model system for dissecting events associated with the host-parasite interactions.

  6. Fatal coinfection with Legionella pneumophila serogroup 8 and Aspergillus fumigatus.

    Science.gov (United States)

    Guillouzouic, Aurélie; Bemer, Pascale; Gay-Andrieu, Françoise; Bretonnière, Cédric; Lepelletier, Didier; Mahé, Pierre-Joachim; Villers, Daniel; Jarraud, Sophie; Reynaud, Alain; Corvec, Stéphane

    2008-02-01

    Legionella pneumophila is an important cause of community-acquired and nosocomial pneumonia. We report on a patient who simultaneously developed L. pneumophila serogroup 8 pneumonia and Aspergillus fumigatus lung abscesses. Despite appropriate treatments, Aspergillus disease progressed with metastasis. Coinfections caused by L. pneumophila and A. fumigatus remain exceptional. In apparently immunocompetent patients, corticosteroid therapy is a key risk factor for aspergillosis.

  7. Isolation of Legionella pneumophila from hotels of Greece.

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    Alexiou, S D; Antoniadis, A; Papapaganagiotou, J; Stefanou, T

    1989-03-01

    Twenty water samples collected from 6 hotels situated in various areas of Greece were examined for the presence of Legionella pneumophila and Legionella-like organisms. Five of the six hotels included in this investigation were associated with cases of legionellosis. Legionella pneumophila serogroups 1 and 8 were isolated from four of six hotels, mainly from the hot water supply system. This is the first isolation and identification of L. pneumophila in Greece.

  8. Multiplication of Legionella pneumophila in unsterilized tap water.

    OpenAIRE

    Yee, R B; Wadowsky, R M

    1982-01-01

    Naturally occurring Legionella pneumophila, an environmental isolate which had not been grown on artificial medium, was tested for the ability to multiply in tap water. A showerhead containing L. pneumophila and non-Legionellaceae bacteria was immersed in nonsterile tap water supplying this fixture. Also L. pneumophila and non-Legionellaceae bacteria were sedimented from tap water from a surgical intensive care unit. This bacterial suspension was inoculated into tap water from our laboratory....

  9. Ciliate Paramecium is a natural reservoir of Legionella pneumophila

    Science.gov (United States)

    Watanabe, Kenta; Nakao, Ryo; Fujishima, Masahiro; Tachibana, Masato; Shimizu, Takashi; Watarai, Masahisa

    2016-04-01

    Legionella pneumophila, the causative agent of Legionnaires’ disease, replicates within alveolar macrophages and free-living amoebae. However, the lifestyle of L. pneumophila in the environment remains largely unknown. Here we established a novel natural host model of L. pneumophila endosymbiosis using the ciliate Paramecium caudatum. We also identified Legionella endosymbiosis-modulating factor A (LefA), which contributes to the change in life stage from endosymbiosis to host lysis, enabling escape to the environment. We isolated L. pneumophila strains from the environment, and they exhibited cytotoxicity toward P. caudatum and induced host lysis. Acidification of the Legionella-containing vacuole (LCV) was inhibited, and enlarged LCVs including numerous bacteria were observed in P. caudatum infected with L. pneumophila. An isogenic L. pneumophila lefA mutant exhibited decreased cytotoxicity toward P. caudatum and impaired the modification of LCVs, resulting in the establishment of endosymbiosis between them. Our results suggest that L. pneumophila may have a mechanism to switch their endosymbiosis in protistan hosts in the environment.

  10. Activities of Tigecycline (GAR-936) against Legionella pneumophila In Vitro and in Guinea Pigs with L. pneumophila Pneumonia

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    Edelstein, Paul H.; Weiss, William J.; Edelstein, Martha A. C.

    2003-01-01

    The activities of tigecycline (Wyeth Research) against extracellular and intracellular Legionella pneumophila and for the treatment of guinea pigs with L. pneumophila pneumonia were studied. The tigecycline MIC at which 50% of strains are inhibited for 101 different Legionella sp. strains was 4 μg/ml versus 0.125 and 0.25 μg/ml for azithromycin and erythromycin, respectively. Tigecycline was about as active as erythromycin (tested at 1 μg/ml) against the F889 strain of L. pneumophila grown in...

  11. Environmental surveillance of Legionella pneumophila in two Italian hospitals

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    Marina Tesauro

    2010-01-01

    Full Text Available The aim of this study was to identify the most effective disinfection protocol to reduce the presence of Legionella pneumophila in the water system of two Italian hospitals. From 2004 to 2009, 271 samplings of hot water were carried out in 11 hospital units to detect the presence of L. pneumophila. Additionally, water samples collected from one boiler outlet and the hot water recirculation were tested. From 2004 to 2009, L. pneumophila was present in 37% of the samples. Of these, 68.3% and 18.8% were positive for serogroups 2-14 and 1, respectively. Furthermore, 12.9% of the samples were positive for both serogroups. Finally, a maximal count of 10(4 CFU/L was measured in the most distal sites. To reduce L. pneumophila colonization, a two-year long hyperchlorination (2004-2006 was carried out. Moreover, from June 2005 until now, continuous maintenance of boilers and tanks, substitution of the shower heads and increase of the boiler outlet temperature to 60 ºC were performed. All these treatments led to a marked reduction of L. pneumophila colonization in the short but not in the medium-long term. Only the use of chlorine dioxide led, after four years, to a reduction of the loads of L. pneumophila to values below 100 CFU/L. However, in the distal sites a persistent degree of colonization (maximum value 700 CFU/L, average 600 CFU/L was observed probably due to the presence of L. pneumophila in the stagnant water in dead legs. In conclusion, data show that long-term chlorination of hot water sources together with carefully aimed maintenance of water pipes can lead to an effective reduction of L. pneumophila concentration in hospital water systems.

  12. Growth regulation of Legionella Pneumophila in biofilms and amoebae; Wachstumsregulation von Legionella Pneumophila in Biofilmen und Amoeben

    Energy Technology Data Exchange (ETDEWEB)

    Hilbi, H.

    2006-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of studies made on the regulation of the growth of Legionella Pneumophila bacteria in biofilms and amoebae. In a first project, the formation of biofilms by Legionella Pneumophila bacteria was analysed in static and dynamic systems using a complex growth medium. Under static and dynamic clinical and environmental conditions, the adherence of the biofilms on polystyrene tissue was studied. This was also examined under dynamic flow conditions. In a second part of the project, the regulation of growth of Legionella Pneumophila in amoebae was examined in that changes were made to the genome of the bacteria. The importance of the work for the de-activation of Legionella Pneumophila bacteria in biofilms is noted in the conclusions of the report.

  13. Post-translational modifications are key players of the Legionella pneumophila infection strategy

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    Michard, Céline; Doublet, Patricia

    2015-01-01

    Post-translational modifications (PTMs) are widely used by eukaryotes to control the enzymatic activity, localization or stability of their proteins. Traditionally, it was believed that the broad biochemical diversity of the PTMs is restricted to eukaryotic cells, which exploit it in extensive networks to fine-tune various and complex cellular functions. During the last decade, the advanced detection methods of PTMs and functional studies of the host–pathogen relationships highlight that bacteria have also developed a large arsenal of PTMs, particularly to subvert host cell pathways to their benefit. Legionella pneumophila, the etiological agent of the severe pneumonia legionellosis, is the paradigm of highly adapted intravacuolar pathogens that have set up sophisticated biochemical strategies. Among them, L. pneumophila has evolved eukaryotic-like and rare/novel PTMs to hijack host cell processes. Here, we review recent progress about the diversity of PTMs catalyzed by Legionella: ubiquitination, prenylation, phosphorylation, glycosylation, methylation, AMPylation, and de-AMPylation, phosphocholination, and de-phosphocholination. We focus on the host cell pathways targeted by the bacteria catalyzed PTMs and we stress the importance of the PTMs in the Legionella infection strategy. Finally, we highlight that the discovery of these PTMs undoubtedly made significant breakthroughs on the molecular basis of Legionella pathogenesis but also lead the way in improving our knowledge of the eukaryotic PTMs and complex cellular processes that are associated to. PMID:25713573

  14. Molecular Evolution of the dotA Gene in Legionella pneumophila

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    Ko, Kwan Soo; Hong, Seong Karp; Lee, Hae Kyung; Park, Mi-Yeoun; Kook, Yoon-Hoh

    2003-01-01

    The molecular evolution of dotA, which is related to the virulence of Legionella pneumophila, was investigated by comparing the sequences of 15 reference strains (serogroups 1 to 15). It was found that dotA has a complex mosaic structure. The whole dotA gene of Legionella pneumophila subsp. pneumophila serogroups 2, 6, and 12 has been transferred from Legionella pneumophila subsp. fraseri. A discrepancy was found between the trees inferred from the nucleotide and deduced amino acid sequences ...

  15. Detection of Legionella pneumophila by real-time PCR for the mip gene.

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    Wilson, Deborah A; Yen-Lieberman, Belinda; Reischl, Udo; Gordon, Steve M; Procop, Gary W

    2003-07-01

    A real-time PCR assay for the mip gene of Legionella pneumophila was tested with 27 isolates of L. pneumophila, 20 isolates of 14 other Legionella species, and 103 non-Legionella bacteria. Eight culture-positive and 40 culture-negative clinical specimens were tested. This assay was 100% sensitive and 100% specific for L. pneumophila.

  16. Isolation of Legionella pneumophila from hospital cooling towers in Johor, Malaysia.

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    Abdul Samad, B H; Suhaili, M R; Baba, N; Rajasekaran, G

    2004-08-01

    Water-based cooling towers and their water supply at two hospitals in Johor were surveyed for the presence Legionella pneumophila. L. pneumophila were grown from 19 (76%) out of 25 collected water samples. One hospital cooling tower was contaminated with L. pneumophila serogroup 1.

  17. Redefining Exploitation

    DEFF Research Database (Denmark)

    Agarwala, Rina

    2016-01-01

    This article examines how self-employed workers are organizing in the garments and waste collection industries in India. Although the question of who is profiting from self-employed workers’ labor is complex, the cases outlined in this paper highlight telling instances of how some self......-employed workers are organizing as workers. They are fighting labor exploitation by redefining the concept to include additional exploitation axes (from the state and middle class) and forms (including sexual). In doing so, they are redefining potential solutions, including identities and material benefits, to fit...... their unique needs. By expanding the category of “workers” beyond those defined by a narrow focus on a standard employer-employee relationship, these movements are also fighting exclusion from earlier labor protections by increasing the number of entitled beneficiaries. These struggles provide an important...

  18. Multiplication of Legionella pneumophila in unsterilized tap water.

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    Yee, R B; Wadowsky, R M

    1982-06-01

    Naturally occurring Legionella pneumophila, an environmental isolate which had not been grown on artificial medium, was tested for the ability to multiply in tap water. A showerhead containing L. pneumophila and non-Legionellaceae bacteria was immersed in nonsterile tap water supplying this fixture. Also L. pneumophila and non-Legionellaceae bacteria were sedimented from tap water from a surgical intensive care unit. This bacterial suspension was inoculated into tap water from our laboratory. The legionellae in both suspensions multiplied in the tap water at 32, 37, and 42 degrees C. The non-Legionellaceae bacteria multiplied at 25, 32, and 37 degrees C. A water sample which was collected from the bottom of a hot water tank was found to contain L. pneumophila and non-Legionellaceae bacteria. These legionellae also multiplied when the water sample was incubated at 37 degrees C. These results indicate that L. pneumophila may multiply in warm water environments such as hot water plumbing fixtures, hot water tanks, and cooling towers.

  19. RavN is a member of a previously unrecognized group of Legionella pneumophila E3 ubiquitin ligases

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    Lin, Yi-Han; Evans, Timothy R.; Doms, Alexandra G.; Beauchene, Nicole A.; Hierro, Aitor

    2018-01-01

    The eukaryotic ubiquitylation machinery catalyzes the covalent attachment of the small protein modifier ubiquitin to cellular target proteins in order to alter their fate. Microbial pathogens exploit this post-translational modification process by encoding molecular mimics of E3 ubiquitin ligases, eukaryotic enzymes that catalyze the final step in the ubiquitylation cascade. Here, we show that the Legionella pneumophila effector protein RavN belongs to a growing class of bacterial proteins that mimic host cell E3 ligases to exploit the ubiquitylation pathway. The E3 ligase activity of RavN was located within its N-terminal region and was dependent upon interaction with a defined subset of E2 ubiquitin-conjugating enzymes. The crystal structure of the N-terminal region of RavN revealed a U-box-like motif that was only remotely similar to other U-box domains, indicating that RavN is an E3 ligase relic that has undergone significant evolutionary alteration. Substitution of residues within the predicted E2 binding interface rendered RavN inactive, indicating that, despite significant structural changes, the mode of E2 recognition has remained conserved. Using hidden Markov model-based secondary structure analyses, we identified and experimentally validated four additional L. pneumophila effectors that were not previously recognized to possess E3 ligase activity, including Lpg2452/SdcB, a new paralog of SidC. Our study provides strong evidence that L. pneumophila is dedicating a considerable fraction of its effector arsenal to the manipulation of the host ubiquitylation pathway. PMID:29415051

  20. Acanthamoeba polyphaga resuscitates viable non-culturable Legionella pneumophila after disinfection.

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    García, María Teresa; Jones, Snake; Pelaz, Carmen; Millar, Richard D; Abu Kwaik, Yousef

    2007-05-01

    Amoebae are the natural hosts for Legionella pneumophila and play essential roles in bacterial ecology and infectivity to humans. When L. pneumophila colonizes an aquatic installation, it can persist for years despite repeated treatments with disinfectants. We hypothesized that freshwater amoebae play an important role in bacterial resistance to disinfectants, and in subsequent resuscitation of viable non-culturable (VNC) L. pneumophila that results in re-emergence of the disease-causing strain in the disinfected water source. Our work showed that in the absence of Acanthamoeba polyphaga, seven L. pneumophila strains became non-culturable after treatment by 256 p.p.m. of sodium hypochlorite (NaOCl). In contrast, intracellular L. pneumophila within A. polyphaga was resistant to 1024 p.p.m. of NaOCl. In addition, L. pneumophila-infected A. polyphaga exhibited increased resistance to NaOCl. When chlorine-sterilized water samples were co-cultured with A. polyphaga, the non-culturable L. pneumophila were resuscitated and proliferated robustly within A. polyphaga. Upon treatment by NaOCl, uninfected amoebae differentiated into cysts within 48 h. In contrast, L. pneumophila-infected A. polyphaga failed to differentiate into cysts, and L. pneumophila was never detected in cysts of A. polyphaga. We conclude that amoebic trophozoites protect intracellular L. pneumophila from eradication by NaOCl, and play an essential role in resuscitation of VNC L. pneumophila in NaOCl-disinfected water sources. Intracellular L. pneumophila within trophozoites of A. polyphaga block encystation of the amoebae, and the resistance of both organisms to NaOCl is enhanced. To ensure long-term eradication and complete loss of the VNC state of L. pneumophila, we recommend that Legionella-protozoa co-culture should be an important tool to ensure complete loss of the VNC state of L. pneumophila.

  1. Legionella pneumophila lung abscess associated with immune suppression.

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    Guy, S D; Worth, L J; Thursky, K A; Francis, P A; Slavin, M A

    2011-10-01

    Legionella species are a common cause of community-acquired pneumonia, infrequently complicated by cavitary disease. We describe Legionella pneumophila pneumonia and abscess formation in an immunosuppressed patient receiving corticosteroid therapy for metastatic breast carcinoma. The predisposing role of corticosteroids is discussed and the management of this complication is reviewed. © 2011 The Authors. Internal Medicine Journal © 2011 Royal Australasian College of Physicians.

  2. An investigation of virulence factors of Legionella pneumophila environmental isolates

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    Elif Özlem Arslan-Aydoğdu

    Full Text Available ABSTRACT Nine Legionella pneumophila strains isolated from cooling towers and a standard strain (L. pneumophila serogroup 1, ATCC 33152, Philadelphia 1 were analyzed and compared in terms of motility, flagella structure, ability to form biofilms, enzymatic activities (hemolysin, nucleases, protease, phospholipase A, phospholipase C, acid phosphatase, alkaline phosphatase and lipase, hemagglutination capabilities, and pathogenicity in various host cells (Acanthamoeba castellanii ATCC 30234, mouse peritoneal macrophages and human peripheral monocytes. All the isolates of bacteria appeared to be motile and polar-flagellated and possessed the type-IV fimbria. Upon the evaluation of virulence factors, isolate 4 was found to be the most pathogenic strain, while 6 out of the 9 isolates (the isolates 1, 2, 3, 4, 5, and 7 were more virulent than the ATCC 33152 strain. The different bacterial strains exhibited differences in properties such as adhesion, penetration and reproduction in the hosts, and preferred host type. To our knowledge, this is the first study to compare the virulence of environmental L. pneumophila strains isolated in Turkey, and it provides important information relevant for understanding the epidemiology of L. pneumophila.

  3. Characterization of a fluorescent compound isolated from Legionella pneumophila

    International Nuclear Information System (INIS)

    Swanson, S.J.

    1987-01-01

    Legionella pneumophila requires the presence of amino acids for growth and utilizes them for energy. Along with other amino acids, either phenylalanine or tyrosine is essential for the growth of the organism and tyrosine has been identified as an energy source. When L. pneumophila is grown in the presence of tyrosine, a brown melanin-like pigment is produced. A green fluorescent pigment, fg2, was isolated from centrifuged culture fluid after the organism was grown in the presence of tyrosine. Fg2 is water soluble with a molecular weight of 152 as determined by mass spectral analysis. A mutant of L. pneumophila unable to produce fg2 was isolated to assist in elucidation of the biosynthesis of fg2. Radiolabeling experiments were utilized to conclude that neither tyrosine nor any other amino acid was a precursor in the biosynthesis of fg2. Shikimic acid, an intermediate in tyrosine biosynthesis, was found to also be an intermediate in the biosynthesis of fg2. A series of experiments in which L. pneumophila was grown in a chemically defined medium containing various combinations of aromatic amino acids determined that fg2 and the brown pigment always occur in tandem

  4. Survey of Legionella pneumophila among pneumonia patients at ...

    African Journals Online (AJOL)

    Objective: To determine the occurrence of L. pneumophila among pneumonia patients at Kenyatta National Hospital and any association with possible risk factors. Design: A cross- sectional descriptive study. Setting: The study was conducted from March to June 2007, at the medical ward of Kenyatta National Hospital.

  5. Genetic typing in a cluster of Legionella pneumophila infections

    NARCIS (Netherlands)

    van Ketel, R. J.; de Wever, B.

    1989-01-01

    Legionella pneumophila strains isolated from six patients, three air-conditioning- and cooling tower-derived strains, and three hot water supply-derived strains were analyzed by three genetic typing methods. The results of the whole-cell DNA restriction endonuclease analysis and the restriction

  6. Legionella pneumophila transcriptome during intracellular multiplication in human macrophages

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    Sebastien P Faucher

    2011-04-01

    Full Text Available Legionella pneumophila is the causative agent of Legionnaires’ disease, an acute pulmonary infection. L. pneumophila is able to infect and multiply in both phagocytic protozoa, such as Acanthamoeba castellanii, and mammalian professional phagocytes. The best-known L. pneumophila virulence determinant is the Icm/Dot Type IVB secretion system (TFBSS, which is used to translocate more than 150 effector proteins to host cells. While the transcriptional response of Legionella to the intracellular environment of A. castellanii has been investigated, much less is known about the Legionella transcriptional response inside human macrophages. In this study, the transcriptome of L. pneumophila was monitored during exponential and post-exponential phase in rich AYE broth as well as during infection of human cultured macrophages. This was accomplished with microarrays and an RNA amplification procedure called SCOTS to detect small amounts of mRNA from low numbers of intracellular bacteria. Among the genes induced intracellularly are those involved in amino acid biosynthetic pathways leading to L-arginine, L-histidine and L-proline as well as many transport systems involved in amino acid and iron uptake. Gene involved in catabolism of glycerol is also induced during intracellular growth and could be used as a carbon source. The genes encoding the Icm/Dot system are not differentially expressed inside cells compared to control bacteria grown in rich broth, but the genes encoding several translocated effectors are strongly induced. Moreover, we used the transcriptome data to predict previously unrecognized Icm/Dot effector genes based on their expression pattern and confirmed translocation for three candidates. This study provides a comprehensive view of how L. pneumophila responds to the human macrophage intracellular environment.

  7. Clinical Application of a Multiplex Real-Time PCR Assay for Simultaneous Detection of Legionella Species, Legionella pneumophila, and Legionella pneumophila Serogroup 1

    OpenAIRE

    Benitez, Alvaro J.; Winchell, Jonas M.

    2014-01-01

    We developed a single-tube multiplex real-time PCR assay capable of simultaneously detecting and discriminating Legionella spp., Legionella pneumophila, and Legionella pneumophila serogroup 1 in primary specimens. Evaluation of 21 clinical specimens and 115 clinical isolates demonstrated this assay to be a rapid, high-throughput diagnostic test with 100% specificity that may aid during legionellosis outbreaks and epidemiologic investigations.

  8. The Amoebal MAP Kinase Response to Legionella pneumophila Is Regulated by DupA

    OpenAIRE

    Li, Zhiru; Dugan, Aisling S.; Bloomfield, Gareth; Skelton, Jason; Ivens, Alasdair; Losick, Vicki; Isberg, Ralph R.

    2009-01-01

    The amoeba Dictyostelium discoideum can support replication of Legionella pneumophila. Here we identify the dupA gene, encoding a putative tyrosine kinase/dual-specificity phosphatase, in a screen for D. discoideum mutants altered in allowing L. pneumophila intracellular replication. Inactivation of dupA resulted in depressed L. pneumophila growth and sustained hyperphosphorylation of the amoebal MAP kinase ERK1, consistent with loss of a phosphatase activity. Bacterial challenge of wild-type...

  9. Severe Pneumonia Caused by Legionella pneumophila: Differential Diagnosis and Therapeutic Considerations.

    Science.gov (United States)

    Chahin, Abdullah; Opal, Steven M

    2017-03-01

    Severe legionella pneumonia poses a diagnostic challenge and requires early intervention. Legionnaire's disease can have several presenting signs, symptoms, and laboratory abnormalities that suggest that Legionella pneumophila is the pathogen, but none of these are sufficient to distinguish L pneumophila pneumonia from other respiratory pathogens. L pneumophila is primarily an intracellular pathogen and needs treatment with antibiotics that efficiently enter the intracellular space. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. The Legionella pneumophila kai operon is implicated in stress response and confers fitness in competitive environments

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    Loza-Correa, Maria; Sahr, Tobias; Rolando, Monica; Daniels, Craig; Petit, Pierre; Skarina, Tania; Valero, Laura Gomez; Dervins-Ravault, Delphine; Honoré, Nadine; Savchenko, Aleksey; Buchrieser, Carmen

    2014-01-01

    Summary Legionella pneumophila uses aquatic protozoa as replication niche and protection from harsh environments. Although L. pneumophila is not known to have a circadian clock, it encodes homologues of the KaiBC proteins of Cyanobacteria that regulate circadian gene expression. We show that L. pneumophila kaiB, kaiC and the downstream gene lpp1114, are transcribed as a unit under the control of the stress sigma factor RpoS. KaiC and KaiB of L. pneumophila do not interact as evidenced by yeast and bacterial two-hybrid analyses. Fusion of the C-terminal residues of cyanobacterial KaiB to Legionella KaiB restores their interaction. In contrast, KaiC of L. pneumophila conserved autophosphorylation activity, but KaiB does not trigger the dephosphorylation of KaiC like in Cyanobacteria. The crystal structure of L. pneumophila KaiB suggests that it is an oxidoreductase-like protein with a typical thioredoxin fold. Indeed, mutant analyses revealed that the kai operon-encoded proteins increase fitness of L. pneumophila in competitive environments, and confer higher resistance to oxidative and sodium stress. The phylogenetic analysis indicates that L. pneumophila KaiBC resemble Synechosystis KaiC2B2 and not circadian KaiB1C1. Thus, the L. pneumophila Kai proteins do not encode a circadian clock, but enhance stress resistance and adaption to changes in the environments. PMID:23957615

  11. Virulence properties of the Legionella pneumophila cell envelope

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    Olga eShevchuk

    2011-04-01

    Full Text Available The bacterial envelope plays a crucial role in the pathogenesis of infectious diseases. In this review, we summarize the current knowledge of the structure and molecular composition of the Legionella pneumophila cell envelope. We describe LPS biosynthesis and the biological activities of membrane and periplasmic proteins and discuss their decisive functions during the pathogen-host interaction. In addition to adherence, invasion and intracellular survival of L. pneumophila, special emphasis is laid on iron acquisition, detoxification, key elicitors of the immune response and the diverse functions of outer membrane vesicles. The critical analysis of the literature reveals that the dynamics and phenotypic plasticity of the Legionella cell surface during the different metabolic stages requires more attention in the future.

  12. Plumbing system shock absorbers as a source of Legionella pneumophila.

    Science.gov (United States)

    Memish, Z A; Oxley, C; Contant, J; Garber, G E

    1992-12-01

    Water distribution systems have been demonstrated to be a major source of nosocomial legionellosis. We describe an outbreak in our institution in which a novel source of Legionella pneumophila was identified in the plumbing system. After an outbreak of 10 cases of legionellosis in our hospital, recommended measures including superheating of the hot water to 80 degrees C, hyperchlorination to 2 ppm, and flushing resulted in no new cases in the following 5 years. Recently, despite these control measures, three new cases occurred. Surveillance cultures of shower heads and water tanks were negative; cultures of tap water samples remained positive. This prompted a search for another reservoir. Shock absorbers installed within water pipes to decrease noise were suspected. One hundred twenty-five shock absorbers were removed and cultured. A total of 13 (10%) yielded heavy growth of L. pneumophila (serogroup 1). Since their removal, no new cases have been found and the percentage of positive results of random tap water culture has dropped from 20% to 5%. This is the first report that identifies shock absorbers as a possible reservoir for L. pneumophila. We recommend that institutions with endemic legionellosis assess the water system for possible removal of shock absorbers.

  13. In Vitro Activity of ABT-773 against Legionella pneumophila, Its Pharmacokinetics in Guinea Pigs, and Its Use to Treat Guinea Pigs with L. pneumophila Pneumonia

    OpenAIRE

    Edelstein, Paul H.; Higa, F.; Edelstein, Martha A. C.

    2001-01-01

    The activity of ABT-773 was studied against extracellular and intracellular Legionella pneumophila and for the treatment of guinea pigs with L. pneumophila pneumonia. The ABT-773 MIC at which 50% of isolates are inhibited (MIC50) for 20 different Legionella sp. strains was 0.016 μg/ml, whereas the MIC50s of clarithromycin and erythromycin were 0.032 and 0.125 μg/ml, respectively. ABT-773 (1 μg/ml) was bactericidal for two L. pneumophila strains grown in guinea pig alveolar macrophages. In con...

  14. Presence and Persistence of Viable, Clinically Relevant Legionella pneumophila Bacteria in Garden Soil in the Netherlands.

    Science.gov (United States)

    van Heijnsbergen, E; van Deursen, A; Bouwknegt, M; Bruin, J P; de Roda Husman, A M; Schalk, J A C

    2016-09-01

    Garden soils were investigated as reservoirs and potential sources of pathogenic Legionella bacteria. Legionella bacteria were detected in 22 of 177 garden soil samples (12%) by amoebal coculture. Of these 22 Legionella-positive soil samples, seven contained Legionella pneumophila Several other species were found, including the pathogenic Legionella longbeachae (4 gardens) and Legionella sainthelensi (9 gardens). The L. pneumophila isolates comprised 15 different sequence types (STs), and eight of these STs were previously isolated from patients according to the European Working Group for Legionella Infections (EWGLI) database. Six gardens that were found to be positive for L. pneumophila were resampled after several months, and in three gardens, L. pneumophila was again isolated. One of these gardens was resampled four times throughout the year and was found to be positive for L. pneumophila on all occasions. Tracking the source of infection for sporadic cases of Legionnaires' disease (LD) has proven to be hard. L. pneumophila ST47, the sequence type that is most frequently isolated from LD patients in the Netherlands, is rarely found in potential environmental sources. As L. pneumophila ST47 was previously isolated from a garden soil sample during an outbreak investigation, garden soils were investigated as reservoirs and potential sources of pathogenic Legionella bacteria. The detection of viable, clinically relevant Legionella strains indicates that garden soil is a potential source of Legionella bacteria, and future research should assess the public health implication of the presence of L. pneumophila in garden soil. Copyright © 2016 van Heijnsbergen et al.

  15. Characterization of an acetyltransferase that detoxifies aromatic chemicals in Legionella pneumophila

    DEFF Research Database (Denmark)

    Kubiak, Xavier Jean Philippe; Dervins-Ravault, Delphine; Pluvinage, Benjamin

    2012-01-01

    Legionella pneumophila is an opportunistic pathogen and the causative agent of Legionnaires' disease. Despite being exposed to many chemical compounds in its natural and man-made habitats (natural aquatic biotopes and man-made water systems), L. pneumophila is able to adapt and survive in these e...

  16. Presence and Persistence of Viable, Clinically Relevant Legionella pneumophila Bacteria in Garden Soil in the Netherlands

    Science.gov (United States)

    van Heijnsbergen, E.; van Deursen, A.; Bouwknegt, M.; Bruin, J. P.; Schalk, J. A. C.

    2016-01-01

    ABSTRACT Garden soils were investigated as reservoirs and potential sources of pathogenic Legionella bacteria. Legionella bacteria were detected in 22 of 177 garden soil samples (12%) by amoebal coculture. Of these 22 Legionella-positive soil samples, seven contained Legionella pneumophila. Several other species were found, including the pathogenic Legionella longbeachae (4 gardens) and Legionella sainthelensi (9 gardens). The L. pneumophila isolates comprised 15 different sequence types (STs), and eight of these STs were previously isolated from patients according to the European Working Group for Legionella Infections (EWGLI) database. Six gardens that were found to be positive for L. pneumophila were resampled after several months, and in three gardens, L. pneumophila was again isolated. One of these gardens was resampled four times throughout the year and was found to be positive for L. pneumophila on all occasions. IMPORTANCE Tracking the source of infection for sporadic cases of Legionnaires' disease (LD) has proven to be hard. L. pneumophila ST47, the sequence type that is most frequently isolated from LD patients in the Netherlands, is rarely found in potential environmental sources. As L. pneumophila ST47 was previously isolated from a garden soil sample during an outbreak investigation, garden soils were investigated as reservoirs and potential sources of pathogenic Legionella bacteria. The detection of viable, clinically relevant Legionella strains indicates that garden soil is a potential source of Legionella bacteria, and future research should assess the public health implication of the presence of L. pneumophila in garden soil. PMID:27316958

  17. Isolation, identification, characterization and antibiotic sensitivity profile of pathogenic Legionella pneumophila isolates from different water sources

    Directory of Open Access Journals (Sweden)

    Kannan Subbaram

    2017-05-01

    Conclusions: Serious and fatal L. pneumophila infections may be transmitted through water. Legionella can survive under various conditions in various water sources. L. pneumophila is the important pathogen causing human disease. Great challenge prevails to health care professionals because these Legionellae acquired antibiotic resistance to many routinely prescribed antibiotics.

  18. Occurrence of Legionella pneumophila and Hartmannella vermiformis in fresh water environments and their interactions in biofilms

    NARCIS (Netherlands)

    Kuiper, M.W.

    2006-01-01

    Legionella pneumophila, the causative agent of Legionnaires’ disease, is widespread in natural fresh water environments and is also frequently found in man-made water systems. Microbial biofilms and protozoa are known to play a major role in the proliferation of L. pneumophila. Biofilms provide

  19. Effect of non-Legionellaceae bacteria on the multiplication of Legionella pneumophila in potable water.

    Science.gov (United States)

    Wadowsky, R M; Yee, R B

    1985-05-01

    A naturally occurring suspension of Legionella pneumophila and associated microbiota contained three unidentified non-Legionellaceae bacteria which supported satellite growth of a subculture of L. pneumophila on an L-cysteine-deficient medium and another bacterium which did not support growth of the subculture. Washed suspensions containing 10(3), 10(5), 10(7), or 10(8) CFU of a mixture of isolates of these non-Legionellaceae bacteria failed to support the multiplication of an isolate of agar-grown L. pneumophila which had been washed and seeded into the suspensions. The suspensions which contained 10(3), 10(5), or 10(7) CFU of the non-Legionellaceae bacteria per ml appeared to enhance survival or cryptic growth of agar-grown L. pneumophila. A decline of 1.3 log CFU of L. pneumophila per ml occurred within the first week of incubation in the sample which contained 10(8) CFU of the non-Legionellaceae bacteria per ml. In contrast to these results, naturally occurring L. pneumophila multiplied in the presence of associated microbiota. The necessity to subculture L. pneumophila and the non-Legionellaceae bacteria on artificial medium to obtain pure cultures may have affected the multiplication of L. pneumophila in tap water. Alternatively, other microorganisms may be present in the naturally occurring suspension which support the growth of this bacterium.

  20. Effect of Legionella pneumophila sonicate on killing of Listeria monocytogenes by human polymorphonuclear neutrophils and monocytes

    DEFF Research Database (Denmark)

    Rechnitzer, C; Bangsborg, Jette Marie; Shand, G H

    1993-01-01

    Legionella pneumophila shares with other intracellular pathogens the ability to resist intracellular killing within phagocytes. An increasing number of cellular components of L. pneumophila are proposed as pathogenic factors of the organism. At the site of infection, the phagocytic cells will be ......Legionella pneumophila shares with other intracellular pathogens the ability to resist intracellular killing within phagocytes. An increasing number of cellular components of L. pneumophila are proposed as pathogenic factors of the organism. At the site of infection, the phagocytic cells...... are most likely to represent the inhibitory factors. The inhibitory activity of L. pneumophila sonic extract appears to be related to inhibition of killing mechanisms since uptake of Listeria was not affected by the sonicate. Our observations indicate that as Legionella infection progresses, bacterial...

  1. Exploring the Legionella pneumophila positivity rate in hotel water samples from Antalya, Turkey.

    Science.gov (United States)

    Sepin Özen, Nevgün; Tuğlu Ataman, Şenay; Emek, Mestan

    2017-05-01

    The genus Legionella is a fastidious Gram-negative bacteria widely distributed in natural waters and man made water supply systems. Legionella pneumophila is the aetiological agent of approximately 90% of reported Legionellosis cases, and serogroup 1 is the most frequent cause of infections. Legionnaires' disease is often associated with travel and continues to be a public health concern at present. The correct water management quality practices and rapid methods for analyzing Legionella species in environmental water is a key point for the prevention of Legionnaires' disease outbreaks. This study aimed to evaluate the positivity rates and serotyping of Legionella species from water samples in the region of Antalya, Turkey, which is an important tourism center. During January-December 2010, a total of 1403 samples of water that were collected from various hotels (n = 56) located in Antalya were investigated for Legionella pneumophila. All samples were screened for L. pneumophila by culture method according to "ISO 11731-2" criteria. The culture positive Legionella strains were serologically identified by latex agglutination test. A total of 142 Legionella pneumophila isolates were recovered from 21 (37.5%) of 56 hotels. The total frequency of L. pneumophila isolation from water samples was found as 10.1%. Serological typing of 142 Legionella isolates by latex agglutination test revealed that strains belonging to L. pneumophila serogroups 2-14 predominated in the examined samples (85%), while strains of L. pneumophila serogroup 1 were less numerous (15%). According to our knowledge, our study with the greatest number of water samples from Turkey demonstrates that L. pneumophila serogroups 2-14 is the most common isolate. Rapid isolation of L. pneumophila from environmental water samples is essential for the investigation of travel related outbreaks and the possible resources. Further studies are needed to have epidemiological data and to determine the types of L

  2. Knowledge to Predict Pathogens: Legionella pneumophila Lifecycle Critical Review Part I Uptake into Host Cells

    Directory of Open Access Journals (Sweden)

    Alexis L. Mraz

    2018-01-01

    Full Text Available Legionella pneumophila (L. pneumophila is an infectious disease agent of increasing concern due to its ability to cause Legionnaires’ Disease, a severe community pneumonia, and the difficulty in controlling it within water systems. L. pneumophila thrives within the biofilm of premise plumbing systems, utilizing protozoan hosts for protection from disinfectants and other environmental stressors. While there is a great deal of information regarding how L. pneumophila interacts with protozoa and human macrophages (host for human infection, the ability to use this data in a model to attempt to predict a concentration of L. pneumophila in a water system is not known. The lifecycle of L. pneumophila within host cells involves three processes: uptake, growth, and egression from the host cell. The complexity of these three processes would risk conflation of the concepts; therefore, this review details the available information regarding how L. pneumophila invades host cells (uptake within the context of data needed to model this process, while a second review will focus on growth and egression. The overall intent of both reviews is to detail how the steps in L. pneumophila’s lifecycle in drinking water systems affect human infectivity, as opposed to detailing just its growth and persistence in drinking water systems.

  3. Effects of metals on Legionella pneumophila growth in drinking water plumbing systems

    Energy Technology Data Exchange (ETDEWEB)

    States, S.J.; Conley, L.F.; Ceraso, M.; Stephenson, T.E.; Wolford, R.S.; Wadowsky, R.M.; McNamara, A.M.; Yee, R.B.

    1985-11-01

    Water samples were collected from hospital and institutional hot-water tanks known to have supported L. pneumophila and were analyzed for 23 chemical parameters. The chemical environment of these tanks was found to vary extensively, with the concentrations of certain metals reaching relatively high levels due to corrosion. The effect of various chemical conditions on L. pneumophila growth was then examined by observing its multiplication in a series of tap water samples artificially supplemented with various concentrations of metals. Additionally, growth of L. pneumophila was examined in a more natural setting by monitoring its multiplication in the chemically analyzed hot-water tank samples after sterilization and reinoculation with L. pneumophila. L. Pneumophila and associated microbiota used in these experiments were obtained from a hot-water tank. These strains were maintained in tap water and had never been passaged on agar. The results of the growth studies indicate that although elevated concentrations of a number of metals are toxic, lower levels of certain metals such as iron, zinc, and potassium enhance growth of naturally occurring L. pneumophila. Parallel observations on accompanying non-Legionellaceae bacteria failed to show the same relationship. These findings suggest that metal plumbing components and associated corrosion products are important factors in the survival and growth of L. pneumophila in plumbing systems and may also be important in related habitats such as cooling towers and air-conditioning systems. 1 figure, 2 tables.

  4. Effects of metals on Legionella pneumophila growth in drinking water plumbing systems.

    Science.gov (United States)

    States, S J; Conley, L F; Ceraso, M; Stephenson, T E; Wolford, R S; Wadowsky, R M; McNamara, A M; Yee, R B

    1985-11-01

    An investigation of the chemical environment and growth of Legionella pneumophila in plumbing systems was conducted to gain a better understanding of its ecology in this habitat. Water samples were collected from hospital and institutional hot-water tanks known to have supported L. pneumophila and were analyzed for 23 chemical parameters. The chemical environment of these tanks was found to vary extensively, with the concentrations of certain metals reaching relatively high levels due to corrosion. The effect of various chemical conditions on L. pneumophila growth was then examined by observing its multiplication in the chemically analyzed hot-water tank samples after sterilization and reinoculation with L. pneumophila. L. pneumophila and associated microbiota used in these experiments were obtained from a hot-water tank. These stains were maintained in tap water and had never been passaged on agar. The results of the growth studies indicate that although elevated concentrations of a number of metals are toxic, lower levels of certain metals such as iron, zinc, and potassium enhance growth of naturally occurring L. pneumophila. Parallel observations on accompanying non-Legionellaceae bacteria failed to show the same relationship. These findings suggest that metal plumbing components and associated corrosion products are important factors in the survival and growth of L. pneumophila in plumbing systems and may also be important in related habitats such as cooling towers and air-conditioning systems.

  5. Bakteri Legionella pneumophila Terdeteksi pada Air Kolam Renang di Kota Surabaya dengan Nested Polymerase Chain Reaction (LEGIONELLA PNEUMOPHILA BACTERIADETECTED IN SWIMMING POOL WATER OF SURABAYA BY USING NESTED POLYMERASE CHAIN REACTION

    Directory of Open Access Journals (Sweden)

    Eduardus Bimo Aksono

    2017-06-01

    Full Text Available Legionella pneumophila is a Gram-negative bacillus that causes nosocomial and community-acquired pneumonia. The aim of this research was to detect the presence of bacteria of L. pneumophila species in the swimming pools water of Surabaya city by using nested Polymerase Chain Reaction (PCR assay of a specific gene for L. pneumophila (mip gene. This study used purposive sampling method. A total of 10 water samples were collected from five swimming pools consisting of 200 mL water for each swimming pool. The results showed that of 10 samples tested by nested PCR, one sample was positive for L. pneumophila, and nine samples were negative. L. pneumophila were found in pool water samples with a higher temperature (>30ºC.Serogrouping analysis of positive sample that L. pneumophila bacteria detected in the water sample of swimming pool in Surabaya was L. pneumophila serogroup 9 (98% and serogroup 10 (98%. L. pneumophila detection of bacteria is expected to raise the awareness of physician and microbiologists about the transmission of L. pneumophila and will also be useful for controlling the agents. ABSTRAK Legionella pneumophila adalah bakteri Gram-negatif berbentuk batang yang dapat menyebabkan penyakit nosokomial dan pneumonia. Tujuan penelitian ini adalah untuk mendeteksi keberadaan bakteri L. pneumophila pada air kolam renang di Kota Surabaya dengan menggunakan nested Polymerase Chain Reaction (PCR berbasis gen spesifik L. pneumophila (mip gene. Penelitian ini menggunakan metode purposive sampling. Sebanyak sepuluh sampel diambil dari lima kolam renang. Sampel diambil sebanyak 200 mL dari air kolam renang di setiap lokasi. Hasil dari 10 sampel yang diuji menggunakan nested PCR, satu sampel menunjukkan hasil positif untuk L.pneumophila, dan sembilan sampel menunjukkan hasil negatif. Bakteri L. pneumophila ditemukan pada sampel air kolam dengan suhu yang lebih tinggi (>30ºC. Satu sampel positip tersebut ketika dilanjutkan terhadap analisis serogrup

  6. Identification of vacuoles containing extraintestinal differentiated forms of Legionella pneumophila in colonized Caenorhabditis elegans soil nematodes.

    Science.gov (United States)

    Hellinga, Jacqueline R; Garduño, Rafael A; Kormish, Jay D; Tanner, Jennifer R; Khan, Deirdre; Buchko, Kristyn; Jimenez, Celine; Pinette, Mathieu M; Brassinga, Ann Karen C

    2015-08-01

    Legionella pneumophila, a causative agent of Legionnaires' disease, is a facultative intracellular parasite of freshwater protozoa. Legionella pneumophila features a unique developmental network that involves several developmental forms including the infectious cyst forms. Reservoirs of L. pneumophila include natural and man-made freshwater systems; however, recent studies have shown that isolates of L. pneumophila can also be obtained directly from garden potting soil suggesting the presence of an additional reservoir. A previous study employing the metazoan Caenorhabditis elegans, a member of the Rhabditidae family of free-living soil nematodes, demonstrated that the intestinal lumen can be colonized with L. pneumophila. While both replicative forms and differentiated forms were observed in C. elegans, these morphologically distinct forms were initially observed to be restricted to the intestinal lumen. Using live DIC imaging coupled with focused transmission electron microscopy analyses, we report here that L. pneumophila is able to invade and establish Legionella-containing vacuoles (LCVs) in the intestinal cells. In addition, LCVs containing replicative and differentiated cyst forms were observed in the pseudocoelomic cavity and gonadal tissue of nematodes colonized with L. pneumophila. Furthermore, establishment of LCVs in the gonadal tissue was Dot/Icm dependent and required the presence of the endocytic factor RME-1 to gain access to maturing oocytes. Our findings are novel as this is the first report, to our knowledge, of extraintestinal LCVs containing L. pneumophila cyst forms in C. elegans tissues, highlighting the potential of soil-dwelling nematodes as an alternate environmental reservoir for L. pneumophila. © 2015 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  7. Non-opsonic phagocytosis of Legionella pneumophila by macrophages is mediated by phosphatidylinositol 3-kinase.

    Directory of Open Access Journals (Sweden)

    Souvenir D Tachado

    Full Text Available BACKGROUND: Legionella pneumophila, is an intracellular pathogen that causes Legionnaires' disease in humans, a potentially lethal pneumonia. L. pneumophila has the ability to enter and replicate in the host and is essential for pathogenesis. METHODOLOGY/PRINCIPAL FINDINGS: Phagocytosis was measured by cell invasion assays. Construction of PI3K mutant by PCR cloning and expression of dominant negative mutant was detected by Western blot. PI3K activity was measured by 32P labeling and detection of phospholipids products by thin layer chromatography. Infection of macrophages with virulent L. pneumophila stimulated the formation of phosphatidylinositol 3-phosphate (PIP3, a phosphorylated lipid product of PI3K whereas two structurally distinct phosphatidylinositol 3 kinase (PI3K inhibitors, wortmannin and LY294002, reduced L. pneumophila entry into macrophages in a dose-dependent fashion. Furthermore, PI3K activation led to Akt stimulation, a serine/threonine kinase, which was also inhibited by wortmannin and LY294002. In contrast, PI3K and protein kinase B (PKB/Akt activities were lower in macrophages infected with an avirulent bacterial strain. Only virulent L. pneumophila increased lipid kinase activity present in immunoprecipitates of the p85alpha subunit of class I PI3K and tyrosine phosphorylated proteins. In addition, macrophages expressing a specific dominant negative mutant of PI3K reduced L. pneumophila entry into these cells. CONCLUSION/SIGNIFICANCE: Entry of L. pneumophila is mediated by PI3K/Akt signaling pathway. These results suggest an important role for PI3K and Akt in the L. pneumophila infection process. They point to possible novel strategies for undermining L. pneumophila host uptake and reducing pathogenesis of Legionnaires' disease.

  8. Necessity and effect of combating Legionella pneumophila in municipal shower systems.

    Directory of Open Access Journals (Sweden)

    Ragnhild Wiik

    Full Text Available The objective was to obtain research-based, holistic knowledge about necessity and effect of practiced measures against L. pneumophila in municipal shower systems in Stavanger, Norway. The effects of hot water treatment and membrane-filtering were investigated and compared to no intervention at all. The studies were done under real-world conditions. Additionally, a surveillance pilot study of municipal showers in Stavanger was performed. The validity of high total plate count (TPC as an indication of L. pneumophila was evaluated. A simplified method, named "dripping method", for detection and quantification of L. pneumophila was developed. The sensitivity of the dripping method is 5 colony-forming units of L. pneumophila/ml. The transference of L. pneumophila from shower water to aerosols was studied. Interviews and observational studies among the stakeholders were done in order to identify patterns of communication and behavior in a Legionella risk perspective. No substantial effects of the measures against L. pneumophila were demonstrated, except for a distally placed membrane filter. No significant positive correlation between TPC and L. pneumophila concentrations were found. L. pneumophila serogroup 2-14 was demonstrated in 21% of the 29 buildings tested in the surveillance pilot. Relatively few cells of L. pneumophila were transferred from shower water to aerosols. Anxiety appeared as the major driving force in the risk governance of Legionella. In conclusion, the risk of acquiring Legionnaires' disease from municipal shower systems is evaluated as low and uncertain. By eliminating ineffective approaches, targeted Legionella risk governance can be practiced. Risk management by surveillance is evaluated as appropriate.

  9. The Ethics of Exploitation

    Directory of Open Access Journals (Sweden)

    Paul McLaughlin

    2008-11-01

    Full Text Available Philosophical inquiry into exploitation has two major deficiencies to date: it assumes that exploitation is wrong by definition; and it pays too much attention to the Marxian account of exploitation. Two senses of exploitation should be distinguished: the ‘moral’ or pejorative sense and the ‘non-moral’ or ‘non-prejudicial’ sense. By demonstrating the conceptual inadequacy of exploitation as defined in the first sense, and by defining exploitation adequately in the latter sense, we seek to demonstrate the moral complexity of exploitation. We contend, moreover, that moral evaluation of exploitation is only possible once we abandon a strictly Marxian framework and attempt, in the long run, to develop an integral ethic along Godwinian lines.

  10. Epidemiology and Ecology of Opportunistic Premise Plumbing Pathogens: Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa

    Science.gov (United States)

    BACKGROUND: Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa are opportunistic premise plumbing pathogens (OPPPs) that persist and grow in household plumbing, habitats they share with humans. Infections caused by these OPPPs involve individuals with preexis...

  11. A multicenter evaluation of genotypic methods for the epidemiologic typing of Legionella pneumophila serogroup 1

    DEFF Research Database (Denmark)

    Fry, Norman K.; Alexiou-Daniel, Stella; Bangsborg, Jette Marie

    1999-01-01

    OBJECTIVES: To compare genotypic methods for epidemiologic typing of Legionella pneumophila serogroup (sg) 1, in order to determine the best available method within Europe for implementation and standardization by members of the European Working Group on Legionella Infections. METHODS: Coded...

  12. Occurrence of Opportunistic Pathogens Legionella pneumophila and non-tuberculous mycobacteria in hospital plumbing systems

    Science.gov (United States)

    Occurrence of Opportunistic Pathogens Legionella pneumophila and non-tuberculous mycobacteria in hospital plumbing systems Jill Hoelle, Michael Coughlin, Elizabeth Sotkiewicz, Jingrang Lu, Stacy Pfaller, Mark Rodgers, and Hodon Ryu U.S. Environmental Protection Agency, Cincinnati...

  13. An ELISA test for the detection of antibodies to Legionella pneumophila.

    OpenAIRE

    Wreghitt, T G; Nagington, J; Gray, J

    1982-01-01

    An enzyme-linked immunosorbent assay (ELISA) test has been developed to detect antibodies to Legionella pneumophila serogroup 1. There is good correlation between indirect fluorescent antibody (IFA) and ELISA titres but ELISA is more sensitive.

  14. Molecular characterization of Legionella pneumophila-induced interleukin-8 expression in T cells

    Directory of Open Access Journals (Sweden)

    Mukaida Naofumi

    2010-01-01

    Full Text Available Abstract Background Legionella pneumophila is the causative agent of human Legionnaire's disease. During infection, the bacterium invades macrophages and lung epithelial cells, and replicates intracellularly. However, little is known about its interaction with T cells. We investigated the ability of L. pneumophila to infect and stimulate the production of interleukin-8 (IL-8 in T cells. The objective of this study was to assess whether L. pneumophila interferes with the immune system by interacting and infecting T cells. Results Wild-type L. pneumophila and flagellin-deficient Legionella, but not L. pneumophila lacking a functional type IV secretion system Dot/Icm, replicated in T cells. On the other hand, wild-type L. pneumophila and Dot/Icm-deficient Legionella, but not flagellin-deficient Legionella or heat-killed Legionella induced IL-8 expression. L. pneumophila activated an IL-8 promoter through the NF-κB and AP-1 binding regions. Wild-type L. pneumophila but not flagellin-deficient Legionella activated NF-κB, p38 mitogen-activated protein kinase (MAPK, Jun N-terminal kinase (JNK, and transforming growth factor β-associated kinase 1 (TAK1. Transfection of dominant negative mutants of IκBα, IκB kinase, NF-κB-inducing kinase, TAK1, MyD88, and p38 MAPK inhibited L. pneumophila-induced IL-8 activation. Inhibitors of NF-κB, p38 MAPK, and JNK blocked L. pneumophila-induced IL-8 expression. In addition, c-Jun, JunD, cyclic AMP response element binding protein, and activating transcription factor 1, which are substrates of p38 MAPK and JNK, bound to the AP-1 site of the IL-8 promoter. Conclusions Taken together, L. pneumophila induced a flagellin-dependent activation of TAK1, p38 MAPK, and JNK, as well as NF-κB and AP-1, which resulted in IL-8 production in human T cells, presumably contributing to the immune response in Legionnaire's disease.

  15. Legionella pneumophila-Derived Outer Membrane Vesicles Promote Bacterial Replication in Macrophages.

    Directory of Open Access Journals (Sweden)

    Anna Lena Jung

    2016-04-01

    Full Text Available The formation and release of outer membrane vesicles (OMVs is a phenomenon of Gram-negative bacteria. This includes Legionella pneumophila (L. pneumophila, a causative agent of severe pneumonia. Upon its transmission into the lung, L. pneumophila primarily infects and replicates within macrophages. Here, we analyzed the influence of L. pneumophila OMVs on macrophages. To this end, differentiated THP-1 cells were incubated with increasing doses of Legionella OMVs, leading to a TLR2-dependent classical activation of macrophages with the release of pro-inflammatory cytokines. Inhibition of TLR2 and NF-κB signaling reduced the induction of pro-inflammatory cytokines. Furthermore, treatment of THP-1 cells with OMVs prior to infection reduced replication of L. pneumophila in THP-1 cells. Blocking of TLR2 activation or heat denaturation of OMVs restored bacterial replication in the first 24 h of infection. With prolonged infection-time, OMV pre-treated macrophages became more permissive for bacterial replication than untreated cells and showed increased numbers of Legionella-containing vacuoles and reduced pro-inflammatory cytokine induction. Additionally, miRNA-146a was found to be transcriptionally induced by OMVs and to facilitate bacterial replication. Accordingly, IRAK-1, one of miRNA-146a's targets, showed prolonged activation-dependent degradation, which rendered THP-1 cells more permissive for Legionella replication. In conclusion, L. pneumophila OMVs are initially potent pro-inflammatory stimulators of macrophages, acting via TLR2, IRAK-1, and NF-κB, while at later time points, OMVs facilitate L. pneumophila replication by miR-146a-dependent IRAK-1 suppression. OMVs might thereby promote spreading of L. pneumophila in the host.

  16. Predictive parameters of Legionella pneumophila occurrence in hospital water: HPCs and plumbing system installation age.

    Science.gov (United States)

    Ghanizadeh, Ghader; Mirmohamadlou, Ali; Esmaeli, Davoud

    2016-09-01

    Occurrence of Legionella pneumophila can be relevant to the installation age and the presence of heterotrophic plate counts (HPCs). This research illustrates L. pneumophila contamination of hospital water in accordance with the installation age and the presence of HPCs. One hundred and fifty samples were collected from hot and cold water systems and cultured on R2A and BCYE agar. L. pneumophila identification was done via specific biochemical tests. HPCs and L. pneumophila were detected in 96 and 37.3 % of the samples, respectively. The mean of HPCs density was 947 ± 998 CFU/ml; therefore, 52 % of the samples had higher densities than 500 CFU/ml. High densities of HPCs (>500 CFU/ml) led to colonization of L. pneumophila (≥1000 CFU/ml), mainly observed in cooling systems, gynecological, sonography, and NICU wards. Chi(2) test demonstrated that higher densities (>500 CFU/ml) of HPCs and L. pneumophila contamination in cold water were more frequent than warm water (OR: 2.3 and 1.49, respectively). Univariate regressions implied a significant difference between HPCs density and installation age in positive and negative tests of L. pneumophila (OR = 1.1, p installation age on L. pneumophila occurrences (p installation age (r s  = 0.33, p installation age are relevant; so, plumbing system renovation with appropriate materials and promotion of the effective efforts for hospital's water quality assurance is highly recommended.

  17. Effect of non-Legionellaceae bacteria on the multiplication of Legionella pneumophila in potable water.

    OpenAIRE

    Wadowsky, R M; Yee, R B

    1985-01-01

    A naturally occurring suspension of Legionella pneumophila and associated microbiota contained three unidentified non-Legionellaceae bacteria which supported satellite growth of a subculture of L. pneumophila on an L-cysteine-deficient medium and another bacterium which did not support growth of the subculture. Washed suspensions containing 10(3), 10(5), 10(7), or 10(8) CFU of a mixture of isolates of these non-Legionellaceae bacteria failed to support the multiplication of an isolate of agar...

  18. Computed tomographic features of 23 sporadic cases with Legionella pneumophila pneumonia

    International Nuclear Information System (INIS)

    Yu Hui; Higa, Futoshi; Hibiya, Kenji; Furugen, Makoto; Sato, Yoko; Shinzato, Takashi; Haranaga, Shusaku; Yara, Satomi; Tateyama, Masao; Fujita, Jiro; Li, Huiping

    2010-01-01

    Objective: To describe the chest computed tomographic (CT) findings of Legionella pneumophila pneumonia. Methods: CT scans obtained from 23 sporadic cases of L. pneumophila pneumonia were retrospectively reviewed. Chest CT findings were analyzed with regard to the patterns and distributions of pulmonary abnormalities. We also analyzed the histopathology of lungs from guinea pigs with experimentally induced L. pneumophila pneumonia. Results: Consolidation and ground-glass opacity (GGO) were the main findings of CT scans in L. pneumophila pneumonia. The distribution of opacities was categorized as non-segmental (n = 20) and segmental (n = 4). Non-segmental distribution may follow an onset of segmental distribution. Pleural effusion was observed in 14 (58.3%) patients, of which 13 were accompanied with non-segmental distribution. Abscess formation was observed in only one immunocompromised patient. In the animal pneumonia model, the lesions comprised of terminal bronchioles, alveolar spaces, and interstitia. Small bacilli were observed to be contained by many macrophages within the alveoli. Conclusion: Non-segmental distribution was significantly more frequent than segmental distribution in L. pneumophila pneumonia. It is possible that L. pneumophila infection initially results in segmental pneumonia, which progresses to typical non-segmental distribution.

  19. Computed tomographic features of 23 sporadic cases with Legionella pneumophila pneumonia

    Energy Technology Data Exchange (ETDEWEB)

    Yu Hui [Department of Respiratory Diseases, Shanghai Pneumology Hospital, Tongji University, Shanghai (China); Higa, Futoshi; Hibiya, Kenji; Furugen, Makoto [Department of Medicine and Therapeutics, Control and Prevention of Infectious Diseases (First Department of Internal Medicine), Faculty of Medicine, University of the Ryukyus, Okinawa (Japan); Sato, Yoko [Tomishiro Chuo Hospital, Okinawa (Japan); Shinzato, Takashi [Nakagami General Hospital, Okinawa (Japan); Haranaga, Shusaku; Yara, Satomi; Tateyama, Masao [Department of Medicine and Therapeutics, Control and Prevention of Infectious Diseases (First Department of Internal Medicine), Faculty of Medicine, University of the Ryukyus, Okinawa (Japan); Fujita, Jiro, E-mail: fujita@med.u-ryukyu.ac.j [Department of Medicine and Therapeutics, Control and Prevention of Infectious Diseases (First Department of Internal Medicine), Faculty of Medicine, University of the Ryukyus, Okinawa (Japan); Li, Huiping [Department of Respiratory Diseases, Shanghai Pneumology Hospital, Tongji University, Shanghai (China)

    2010-06-15

    Objective: To describe the chest computed tomographic (CT) findings of Legionella pneumophila pneumonia. Methods: CT scans obtained from 23 sporadic cases of L. pneumophila pneumonia were retrospectively reviewed. Chest CT findings were analyzed with regard to the patterns and distributions of pulmonary abnormalities. We also analyzed the histopathology of lungs from guinea pigs with experimentally induced L. pneumophila pneumonia. Results: Consolidation and ground-glass opacity (GGO) were the main findings of CT scans in L. pneumophila pneumonia. The distribution of opacities was categorized as non-segmental (n = 20) and segmental (n = 4). Non-segmental distribution may follow an onset of segmental distribution. Pleural effusion was observed in 14 (58.3%) patients, of which 13 were accompanied with non-segmental distribution. Abscess formation was observed in only one immunocompromised patient. In the animal pneumonia model, the lesions comprised of terminal bronchioles, alveolar spaces, and interstitia. Small bacilli were observed to be contained by many macrophages within the alveoli. Conclusion: Non-segmental distribution was significantly more frequent than segmental distribution in L. pneumophila pneumonia. It is possible that L. pneumophila infection initially results in segmental pneumonia, which progresses to typical non-segmental distribution.

  20. The Legionella pneumophila Collagen-Like Protein Mediates Sedimentation, Autoaggregation, and Pathogen-Phagocyte Interactions

    Science.gov (United States)

    Abdel-Nour, Mena; Duncan, Carla; Prashar, Akriti; Rao, Chitong; Ginevra, Christophe; Jarraud, Sophie; Low, Donald E.; Ensminger, Alexander W.; Terebiznik, Mauricio R.

    2014-01-01

    Although only partially understood, multicellular behavior is relatively common in bacterial pathogens. Bacterial aggregates can resist various host defenses and colonize their environment more efficiently than planktonic cells. For the waterborne pathogen Legionella pneumophila, little is known about the roles of autoaggregation or the parameters which allow cell-cell interactions to occur. Here, we determined the endogenous and exogenous factors sufficient to allow autoaggregation to take place in L. pneumophila. We show that isolates from Legionella species which do not produce the Legionella collagen-like protein (Lcl) are deficient in autoaggregation. Targeted deletion of the Lcl-encoding gene (lpg2644) and the addition of Lcl ligands impair the autoaggregation of L. pneumophila. In addition, Lcl-induced autoaggregation requires divalent cations. Escherichia coli producing surface-exposed Lcl is able to autoaggregate and shows increased biofilm production. We also demonstrate that L. pneumophila infection of Acanthamoeba castellanii and Hartmanella vermiformis is potentiated under conditions which promote Lcl dependent autoaggregation. Overall, this study shows that L. pneumophila is capable of autoaggregating in a process that is mediated by Lcl in a divalent-cation-dependent manner. It also reveals that Lcl potentiates the ability of L. pneumophila to come in contact, attach, and infect amoebae. PMID:24334670

  1. The Legionella pneumophila GIG operon responds to gold and copper in planktonic and biofilm cultures.

    Directory of Open Access Journals (Sweden)

    Kathleen Jwanoswki

    Full Text Available Legionella pneumophila contaminates man-made water systems and creates numerous exposure risks for Legionnaires' Disease. Because copper/silver ionization is commonly used to control L. pneumophila, its mechanisms of metal response and detoxification are of significant interest. Here we describe an L. pneumophila operon with significant similarity to the GIG operon of Cupriavidus metallidurans. The Legionella GIG operon is present in a subset of strains and has been acquired as part of the ICE-βox 65-kB integrative conjugative element. We assessed GIG promoter activity following exposure of L. pneumophila to multiple concentrations of HAuCl4, CuSO4 and AgNO3. At 37°C, control stationary phase cultures exhibited GIG promoter activity. This activity increased significantly in response to 20 and 50uM HAuCl4 and CuSO4 but not in response to AgNO3. Conversely, at 26°C, cultures exhibited decreased promoter response to copper. GIG promoter activity was also induced by HAuCl4 or CuSO4 during early biofilm establishment at both temperatures. When an L. pneumophila GIG promoter construct was transformed into E. coli DH5α, cultures showed baseline expression levels that did not increase following metal addition. Analysis of L. pneumophila transcriptional regulatory mutants suggested that GIG up-regulation in the presence of metal ions may be influenced by the stationary phase sigma factor, RpoS.

  2. The Legionella pneumophila GIG operon responds to gold and copper in planktonic and biofilm cultures.

    Science.gov (United States)

    Jwanoswki, Kathleen; Wells, Christina; Bruce, Terri; Rutt, Jennifer; Banks, Tabitha; McNealy, Tamara L

    2017-01-01

    Legionella pneumophila contaminates man-made water systems and creates numerous exposure risks for Legionnaires' Disease. Because copper/silver ionization is commonly used to control L. pneumophila, its mechanisms of metal response and detoxification are of significant interest. Here we describe an L. pneumophila operon with significant similarity to the GIG operon of Cupriavidus metallidurans. The Legionella GIG operon is present in a subset of strains and has been acquired as part of the ICE-βox 65-kB integrative conjugative element. We assessed GIG promoter activity following exposure of L. pneumophila to multiple concentrations of HAuCl4, CuSO4 and AgNO3. At 37°C, control stationary phase cultures exhibited GIG promoter activity. This activity increased significantly in response to 20 and 50uM HAuCl4 and CuSO4 but not in response to AgNO3. Conversely, at 26°C, cultures exhibited decreased promoter response to copper. GIG promoter activity was also induced by HAuCl4 or CuSO4 during early biofilm establishment at both temperatures. When an L. pneumophila GIG promoter construct was transformed into E. coli DH5α, cultures showed baseline expression levels that did not increase following metal addition. Analysis of L. pneumophila transcriptional regulatory mutants suggested that GIG up-regulation in the presence of metal ions may be influenced by the stationary phase sigma factor, RpoS.

  3. A Multiplex PCR for Detection of Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila, and Bordetella pertussis in Clinical Specimens

    National Research Council Canada - National Science Library

    McDonough, E. A; Barrozo, C. P; Russell, K. L; Metzgar, D

    2005-01-01

    A multiplex PCR was developed that is capable of detecting four of the most important bacterial agents of atypical pneumophia, Mycaplasma pneumoniae, Chlamydophia pneumoniae, Legionella pneumophila...

  4. Legionella pneumophila control in practice. Legionellenbekaempfung in der Praxis

    Energy Technology Data Exchange (ETDEWEB)

    Scharff, K

    1989-01-01

    Legionella pneumophila are wide-spread, rod-shaped bacilli (24 species with 40 serogroups are known to date) which preferably occur in water (lower growth limit is at 20deg C). Details are given on recommendations issued by the Federal Public Health Office. Thermal disinfection should be preferred to a chemical disinfection of drinking water. Recommendations such as water heating to 60deg C, regular cleaning of central clear-water reservoirs, self-draining shower hoses and shower heads, shut-off of unused pipe sections and connecting pipes should be put into practice applying easy-to-handle 60deg C tap water heating systems, circulating pipes, heated inlet pipes, decentralized flow heaters, storage system cleaning and pipe shut-off measures. Legionella research needs to be continued. (HWJ).

  5. Exploit Kit traffic analysis

    OpenAIRE

    Καπίρης, Σταμάτης; Kapiris, Stamatis

    2017-01-01

    Exploit kits have become one of the most widespread and destructive threat that Internet users face on a daily basis. Since the first actor, which has been categorized as exploit kit, namely MPack, appeared in 2006, we have seen a new era on exploit kit variants compromising popular websites, infecting hosts and delivering destructive malware, following an exponentially evolvement to date. With the growing threat landscape, large enterprises to domestic networks, have starte...

  6. Exploitability Assessment with TEASER

    Science.gov (United States)

    2017-05-01

    for architectural neutral taint analysis on top of LLVM and QEMU. POC Proof of Concept : Demonstration of an exploit on a program . vii RCE Remote Code...bug with a Proof of Concept (POC), or input to a program demonstrating the ability to use a bug to exploit the application, to demonstrate the...often leads to either computationally difficult constraint solving problems or taint explosion. Given the computational difficulty of exploit

  7. [The hazards of hospitals and selected public buildings of Legionella pneumophila].

    Science.gov (United States)

    Sikora, Agnieszka; Kozioł-Montewka, Maria; Wójtowicz-Bobin, Małgorzata; Gładysz, Iwona; Dobosz, Paulina

    2013-11-01

    The registered infection and outbreaks of epidemic tend to monitor potential reservoirs of Legionella infection. According to the Act of 29 March 2007 on the requirements for the quality of water intended for human consumption are required to test for the presence and number of Legionella in the water system of hospitals. In case of detection of L. pneumophila serogroup 1 (SG 1) or increased above normal number other serogroups of bacteria it is necessary to eradicate these bacteria from the water system. The aim of this study was to assess the degree of contamination of the water supply system of selected public buildings and analyze the effectiveness of disinfection methods for the elimination of L. pneumophila in hot water systems. The materials for this study were hot and cold water samples which were collected from the water supply system of 23 different objects. Enumeration of Legionella bacteria in water samples was determined by membrane filtration (FM) and/or by surface inoculation methods according to the standards: PN-ISO 11731: 2002: "The quality of the water. Detection and enumeration of Legionella" and PN-EN ISO 11731-2: 2008: "Water quality--Detection and enumeration of Legionella--Part 2: Methodology of membrane filtration for water with a small number of bacteria". L. pneumophila was present in 164 samples of hot water, which accounted for 76.99%. In all tested water samples L. pneumophila SG 2-14 strains were detected. The most virulent strain--L. pneumophila SG 1 was not detected. In examined 23 objects in 12 of L. pneumophila exceed acceptable levels > 100 CFU/100 ml. The presence of L. pneumophila SG 2-14 demonstrated in all examined objects, indicating the risk of infection, and the need for permanent monitoring of the water system supply. The thermal disinfection is the most common, inexpensive, and effective method of control of L. pneumophila used in examined objects, but does not eliminate bacterial biofilm. Disinfection using the filters

  8. Anthropology of sexual exploitation

    Directory of Open Access Journals (Sweden)

    Lalić Velibor

    2009-01-01

    Full Text Available In this paper, the authors observe sexual exploitation from an anthropological perspective. They analyze the rational, ethical, emotional and mythological dimensions of human sexuality. Consequently, after setting the phenomenon in a social and historical context, sexual exploitation is closely observed in the contemporary age. Based on thoughts of relevant thinkers, they make the conclusion that the elimination of sexual exploitation is not an utterly legal issue, but political and economical issues as well. Namely, legal norms are not sufficient to overcome sexual exploitation, but, political and economical relationships in contemporary societies, which will be based on sincere equal opportunities must be established.

  9. Exploitation and disadvantage

    NARCIS (Netherlands)

    Ferguson, B.

    2016-01-01

    According to some accounts of exploitation, most notably Ruth Sample's (2003) degradation-based account and Robert Goodin's (1987) vulnerability-based account, exploitation occurs when an advantaged party fails to constrain their advantage in light of another's disadvantage, regardless of the cause

  10. EXPLOITATION OF GRANITE BOULDER

    Directory of Open Access Journals (Sweden)

    Ivan Cotman

    1994-12-01

    Full Text Available The processes of forming, petrography, features, properties and exploitation of granite boulders are described. The directional drilling and black powder blasting is the succesful method in exploitation of granite boulders (boulder technology (the paper is published in Croatian.

  11. Role of biofilm roughness and hydrodynamic conditions in Legionella pneumophila adhesion to and detachment from simulated drinking water biofilms.

    Science.gov (United States)

    Shen, Yun; Monroy, Guillermo L; Derlon, Nicolas; Janjaroen, Dao; Huang, Conghui; Morgenroth, Eberhard; Boppart, Stephen A; Ashbolt, Nicholas J; Liu, Wen-Tso; Nguyen, Thanh H

    2015-04-07

    Biofilms in drinking water distribution systems (DWDS) could exacerbate the persistence and associated risks of pathogenic Legionella pneumophila (L. pneumophila), thus raising human health concerns. However, mechanisms controlling adhesion and subsequent detachment of L. pneumophila associated with biofilms remain unclear. We determined the connection between L. pneumophila adhesion and subsequent detachment with biofilm physical structure characterization using optical coherence tomography (OCT) imaging technique. Analysis of the OCT images of multispecies biofilms grown under low nutrient condition up to 34 weeks revealed the lack of biofilm deformation even when these biofilms were exposed to flow velocity of 0.7 m/s, typical flow for DWDS. L. pneumophila adhesion on these biofilm under low flow velocity (0.007 m/s) positively correlated with biofilm roughness due to enlarged biofilm surface area and local flow conditions created by roughness asperities. The preadhered L. pneumophila on selected rough and smooth biofilms were found to detach when these biofilms were subjected to higher flow velocity. At the flow velocity of 0.1 and 0.3 m/s, the ratio of detached cell from the smooth biofilm surface was from 1.3 to 1.4 times higher than that from the rough biofilm surface, presumably because of the low shear stress zones near roughness asperities. This study determined that physical structure and local hydrodynamics control L. pneumophila adhesion to and detachment from simulated drinking water biofilm, thus it is the first step toward reducing the risk of L. pneumophila exposure and subsequent infections.

  12. Planktonic replication is essential for biofilm formation by Legionella pneumophila in a complex medium under static and dynamic flow conditions

    DEFF Research Database (Denmark)

    Mampel, J.; Spirig, T.; Weber, S.S.

    2006-01-01

    Legionella pneumophila persists for a long time in aquatic habitats, where the bacteria associate with biofilms and replicate within protozoan predators. While L. pneumophila serves as a paradigm for intracellular growth within protozoa, it is less clear whether the bacteria form or replicate...

  13. Detection of protozoan hosts for Legionella pneumophila in engineered water systems by using a biofilm batch test

    NARCIS (Netherlands)

    Valster, R.M.; Wullings, B.A.; Kooij, van der D.

    2010-01-01

    Legionella pneumophila proliferates in aquatic habitats within free-living protozoa, 17 species of which have been identified as hosts by using in vitro experiments. The present study aimed at identifying protozoan hosts for L. pneumophila by using a biofilm batch test (BBT). Samples (600 ml)

  14. Severe Community-acquired Pneumonia Due to Legionella pneumophila Serogroup 6

    Directory of Open Access Journals (Sweden)

    Chung-Yu Chen

    2006-01-01

    Full Text Available Legionella pneumophila is a common cause of sporadic community-acquired pneumonia, but culture-proven legionellosis is rarely diagnosed. There is no laboratory test for Legionnaires' disease that can detect all patients with the disease. Culture is the standard diagnostic method and should be initiated as soon as possible in suspected cases. We describe a rare case of community-acquired pneumonia caused by L. pneumophila serogroup 6. A 77-year-old man was admitted to a tertiary care hospital because of high fever, productive cough, and progressive dyspnea. Chest radiography showed bilateral pneumonia, which led to respiratory failure necessitating mechanical ventilatory support. Despite antibiotic therapy, his condition continued to deteriorate and acute renal failure also developed. Urine was negative for L. pneumophila. Culture of the sputum yielded L. pneumophila serogroup 6, although there was no elevation of the serum antibody titer. Pneumonia resolved gradually and he was extubated after treatment with levofloxacin followed by erythromycin. L. pneumophila other than serogroup 1 should be included in the differential diagnosis of patients with suspected atypical community-acquired pneumonia.

  15. The transcriptome of Legionella pneumophila-infected human monocyte-derived macrophages.

    Directory of Open Access Journals (Sweden)

    Christopher T D Price

    Full Text Available Legionella pneumophila is an intracellular bacterial pathogen that invades and replicates within alveolar macrophages through injection of ∼ 300 effector proteins by its Dot/Icm type IV translocation apparatus. The bona fide F-box protein, AnkB, is a nutritional virulence effector that triggers macrophages to generate a surplus of amino acids, which is essential for intravacuolar proliferation. Therefore, the ankB mutant represents a novel genetic tool to determine the transcriptional response of human monocyte-derived macrophages (hMDMs to actively replicating L. pneumophila.Here, we utilized total human gene microarrays to determine the global transcriptional response of hMDMs to infection by wild type or the ankB mutant of L. pneumophila. The transcriptomes of hMDMs infected with either actively proliferating wild type or non-replicative ankB mutant bacteria were remarkably similar. The transcriptome of infected hMDMs was predominated by up-regulation of inflammatory pathways (IL-10 anti-inflammatory, interferon signaling and amphoterin signaling, anti-apoptosis, and down-regulation of protein synthesis pathways. In addition, L. pneumophila modulated diverse metabolic pathways, particularly those associated with bio-active lipid metabolism, and SLC amino acid transporters expression.Taken together, the hMDM transcriptional response to L. pneumophila is independent of intra-vacuolar replication of the bacteria and primarily involves modulation of the immune response and metabolic as well as nutritional pathways.

  16. Detection limits of Legionella pneumophila in environmental samples after co-culture with Acanthamoeba polyphaga

    Science.gov (United States)

    2013-01-01

    Background The efficiency of recovery and the detection limit of Legionella after co-culture with Acanthamoeba polyphaga are not known and so far no investigations have been carried out to determine the efficiency of the recovery of Legionella spp. by co-culture and compare it with that of conventional culturing methods. This study aimed to assess the detection limits of co-culture compared to culture for Legionella pneumophila in compost and air samples. Compost and air samples were spiked with known concentrations of L. pneumophila. Direct culturing and co-culture with amoebae were used in parallel to isolate L. pneumophila and recovery standard curves for both methods were produced for each sample. Results The co-culture proved to be more sensitive than the reference method, detecting 102-103 L. pneumophila cells in 1 g of spiked compost or 1 m3 of spiked air, as compared to 105-106 cells in 1 g of spiked compost and 1 m3 of spiked air. Conclusions Co-culture with amoebae is a useful, sensitive and reliable technique to enrich L. pneumophila in environmental samples that contain only low amounts of bacterial cells. PMID:23442526

  17. The amoebal MAP kinase response to Legionella pneumophila is regulated by DupA.

    Science.gov (United States)

    Li, Zhiru; Dugan, Aisling S; Bloomfield, Gareth; Skelton, Jason; Ivens, Alasdair; Losick, Vicki; Isberg, Ralph R

    2009-09-17

    The amoeba Dictyostelium discoideum can support replication of Legionella pneumophila. Here we identify the dupA gene, encoding a putative tyrosine kinase/dual-specificity phosphatase, in a screen for D. discoideum mutants altered in allowing L. pneumophila intracellular replication. Inactivation of dupA resulted in depressed L. pneumophila growth and sustained hyperphosphorylation of the amoebal MAP kinase ERK1, consistent with loss of a phosphatase activity. Bacterial challenge of wild-type amoebae induced dupA expression and resulted in transiently increased ERK1 phosphorylation, suggesting that dupA and ERK1 are part of a response to bacteria. Indeed, over 500 of the genes misregulated in the dupA(-) mutant were regulated in response to L. pneumophila infection, including some thought to have immune-like functions. MAP kinase phosphatases are known to be highly upregulated in macrophages challenged with L. pneumophila. Thus, DupA may regulate a MAP kinase response to bacteria that is conserved from amoebae to mammals.

  18. Poverty-Exploitation-Alienation.

    Science.gov (United States)

    Bronfenbrenner, Martin

    1980-01-01

    Illustrates how knowledge derived from the discipline of economics can be used to help shed light on social problems such as poverty, exploitation, and alienation, and can help decision makers form policy to minimize these and similar problems. (DB)

  19. Exploiting VM/XA

    International Nuclear Information System (INIS)

    Boeheim, C.

    1990-03-01

    The Stanford Linear Accelerator Center has recently completed a conversion to IBM's VM/XA SP Release 2 operating system. The primary physics application had been constrained by the previous 16 megabyte memory limit. Work is underway to enable this application to exploit the new features of VM/XA. This paper presents a brief tutorial on how to convert an application to exploit VM/XA and discusses some of the SLAC experiences in doing so. 13 figs

  20. Legionella pneumophila secretes a mitochondrial carrier protein during infection.

    Directory of Open Access Journals (Sweden)

    Pavel Dolezal

    2012-01-01

    Full Text Available The Mitochondrial Carrier Family (MCF is a signature group of integral membrane proteins that transport metabolites across the mitochondrial inner membrane in eukaryotes. MCF proteins are characterized by six transmembrane segments that assemble to form a highly-selective channel for metabolite transport. We discovered a novel MCF member, termed Legionellanucleotide carrier Protein (LncP, encoded in the genome of Legionella pneumophila, the causative agent of Legionnaire's disease. LncP was secreted via the bacterial Dot/Icm type IV secretion system into macrophages and assembled in the mitochondrial inner membrane. In a yeast cellular system, LncP induced a dominant-negative phenotype that was rescued by deleting an endogenous ATP carrier. Substrate transport studies on purified LncP reconstituted in liposomes revealed that it catalyzes unidirectional transport and exchange of ATP transport across membranes, thereby supporting a role for LncP as an ATP transporter. A hidden Markov model revealed further MCF proteins in the intracellular pathogens, Legionella longbeachae and Neorickettsia sennetsu, thereby challenging the notion that MCF proteins exist exclusively in eukaryotic organisms.

  1. Susceptibility of Legionella pneumophila to chlorine in tap water.

    Science.gov (United States)

    Kuchta, J M; States, S J; McNamara, A M; Wadowsky, R M; Yee, R B

    1983-11-01

    A study was conducted to compare the susceptibility of legionellae and coliforms to disinfection by chlorine. The chlorine residuals used were similar to concentrations that might be found in the distribution systems of large public potable water supplies. The effects of various chlorine concentrations, temperatures, and pH levels were considered. A number of different Legionella strains, both environmental and clinical, were tested. The results indicate that legionellae are much more resistant to chlorine than are coliform bacteria. At 21 degrees C, pH 7.6, and 0.1 mg of free chlorine residual per liter, a 99% kill of L. pneumophila was achieved within 40 min, compared with less than 1 min for Escherichia coli. The observed resistance is enhanced as conditions for disinfection become less optimal. The required contact time for the removal of L. pneumophilia was twice as long at 4 degrees C than it was at 21 degrees C. These data suggest that legionellae can survive low levels of chlorine for relatively long periods of time.

  2. Isolation and identification of Legionella pneumophila from drinking water in Basra governorate, Iraq.

    Science.gov (United States)

    Al-Sulami, A A; Al-Taee, A M R; Yehyazarian, A A

    2013-11-01

    This study in Iraq investigated the occurrence of Legionella. pneumophila in different drinking-water sources in Basra governorate as well as the susceptibility of isolates to several antibiotics. A total of 222 water samples were collected in 2008-2009: 49 samples from water purification plants (at entry points, from precipitation tanks, from filtration tanks and at exit points), 127 samples of tap water; and 46 samples from tankers and plants supplying water by reverse osmosis. The findings confirmed the presence of L. pneumophila in sources of crude water, in general drinking water supplies and drinking water tankers. Of 258 isolates 77.1% were serotype 1 and 22.9% serotypes 2-15. All examined isolates displayed drug resistance, particularly to ampicillin, but were 100% susceptible to doxycycline. The prevalence of L. pneumophila, especially serogroup 1, is a strong indicator of unsuitability of drinking water and requires appropriate action.

  3. [Genomic DNA fingerprints of Legionella pneumophila serogroup 2 strains as an epidemiologic marker].

    Science.gov (United States)

    Bender-Beck, L; Mühlenberg, W; Lück, P C; Ott, M; Horbach, I; Fehrenbach, F J; Wewalka, G; Hacker, J

    1995-08-01

    Using pulsed-field gel electrophoresis, DNA fingerprints of eleven Legionella pneumophila isolates of serogroup 2 were generated. It was shown that two strains from a patient suffering from pneumonia as well as three environmental strains isolated from the shower in the hotel where the patient stayed 5 days before his illness were identical. Six strains of the same serogroup isolated from other sources were clearly separated. Thus, DNA fingerprints by pulsed-field gel electrophoresis are excellent epidemiological markers for the rarely occurring serogroup 2 of Legionella pneumophila.

  4. Topology of Legionella pneumophila DotA: an inner membrane protein required for replication in macrophages.

    OpenAIRE

    Roy, C R; Isberg, R R

    1997-01-01

    The Legionella pneumophila dotA gene is required for intracellular growth of the bacterium in macrophages. In this study, a structure-function analysis of the DotA protein was conducted to elucidate the role of this protein in L. pneumophila pathogenesis. Translational fusions of dotA to the Escherichia coli phoA and lacZ genes indicated that DotA is an integral cytoplasmic membrane protein with eight membrane-spanning domains. DotA contains two large periplasmic domains of approximately 503 ...

  5. Effect of temperature, pH, and oxygen level on the multiplication of naturally occurring Legionella pneumophila in potable water.

    Science.gov (United States)

    Wadowsky, R M; Wolford, R; McNamara, A M; Yee, R B

    1985-05-01

    A water culture containing naturally occurring Legionella pneumophila and associated microbiota was maintained in the laboratory by serially transferring the culture in tap water which had been sterilized by membrane filtration. Successful maintenance of the water culture depended upon transferring the culture when the growth of L. pneumophila was in the late-exponential to early-stationary phase. The water culture was used as a source of naturally occurring bacteria to determine some of the parameters which affect the multiplication of L. pneumophila in tap water. Naturally occurring L. pneumophila multiplied at a temperature between 25 and 37 degrees C, at pH levels of 5.5 to 9.2, and at concentrations of dissolved oxygen of 6.0 to 6.7 mg/liter. Multiplication did not occur in tap water which contained less than 2.2 mg of dissolved oxygen per liter. An association was observed between the multiplication of L. pneumophila and the non-Legionellaceae bacteria which were also present in the water culture. The method of preserving naturally occurring L. pneumophila and associated microbiota may facilitate studies on the symbiosis of L. pneumophila with other microorganisms.

  6. Dissemination and Exploitation Strategy

    DEFF Research Database (Denmark)

    Badger, Merete; Monaco, Lucio; Fransson, Torsten

    of Technology in Sweden, Politecnico di Torino in Italy, and Eindhoven University of Technology in the Netherlands. The project is partially funded by the European Commission under the 7th Framework Programme (project no. RI-283746). This report describes the final dissemination and exploitation strategy...... for project Virtual Campus Hub. A preliminary dissemination and exploitation plan was setup early in the project as described in the deliverable D6.1 Dissemination strategy paper - preliminary version. The plan has been revised on a monthly basis during the project’s lifecycle in connection with the virtual...

  7. Growth-supporting activity for Legionella pneumophila in tap water cultures and implication of hartmannellid amoebae as growth factors.

    Science.gov (United States)

    Wadowsky, R M; Butler, L J; Cook, M K; Verma, S M; Paul, M A; Fields, B S; Keleti, G; Sykora, J L; Yee, R B

    1988-11-01

    Photosynthetic cyanobacteria, heterotrophic bacteria, free-living amoebae, and ciliated protozoa may support growth of Legionella pneumophila. Studies were done with two tap water cultures (WS1 and WS2) containing L. pneumophila and associated microbiota to characterize growth-supporting activity and assess the relative importance of the microbiota in supporting multiplication of L. pneumophila. The water cultures were incubated in the dark at 35 degrees C. The growth-supporting factor(s) was separated from each culture by filtration through 1-micron-pore-size membrane filters. The retentate was then suspended in sterile tap water. Multiplication of L. pneumophila occurred when both the retentate suspension and the filtrate from either culture were inoculated into sterile tap water. L. pneumophila did not multiply in tap water inoculated with only the filtrate, even though filtration did not reduce the concentration of L. pneumophila or heterotrophic bacteria in either culture. Growth-supporting activity of the retentate suspension from WS1 was inactivated at 60 degrees C but unaffected at 0, 25, and 45 degrees C after 30-min incubations. Filtration experiments indicated that the growth-supporting factor(s) in WS1 was 2 to 5 micron in diameter. Ciliated protozoa were not detected in either culture. Hartmannellid amoebae were conclusively demonstrated in WS2 but not in WS1. L. pneumophila multiplied in tap water inoculated with the amoebae (10(3)/ml) and the 1-micron filtrate of WS2. No multiplication occurred in tap water inoculated with the filtrate only. Growth-supporting activity for L. pneumophila may be present in plumbing systems; hartmannellid amoebae appear to be important determinants of multiplication of L. pneumophila in some tap water cultures.

  8. Legionella pneumophila Carbonic Anhydrases: Underexplored Antibacterial Drug Targets

    Directory of Open Access Journals (Sweden)

    Claudiu T. Supuran

    2016-06-01

    Full Text Available Carbonic anhydrases (CAs, EC 4.2.1.1 are metalloenzymes which catalyze the hydration of carbon dioxide to bicarbonate and protons. Many pathogenic bacteria encode such enzymes belonging to the α-, β-, and/or γ-CA families. In the last decade, enzymes from some of these pathogens, including Legionella pneumophila, have been cloned and characterized in detail. These enzymes were shown to be efficient catalysts for CO2 hydration, with kcat values in the range of (3.4–8.3 × 105 s−1 and kcat/KM values of (4.7–8.5 × 107 M−1·s−1. In vitro inhibition studies with various classes of inhibitors, such as anions, sulfonamides and sulfamates, were also reported for the two β-CAs from this pathogen, LpCA1 and LpCA2. Inorganic anions were millimolar inhibitors, whereas diethyldithiocarbamate, sulfamate, sulfamide, phenylboronic acid, and phenylarsonic acid were micromolar ones. The best LpCA1 inhibitors were aminobenzolamide and structurally similar sulfonylated aromatic sulfonamides, as well as acetazolamide and ethoxzolamide (KIs in the range of 40.3–90.5 nM. The best LpCA2 inhibitors belonged to the same class of sulfonylated sulfonamides, together with acetazolamide, methazolamide, and dichlorophenamide (KIs in the range of 25.2–88.5 nM. Considering such preliminary results, the two bacterial CAs from this pathogen represent promising yet underexplored targets for obtaining antibacterials devoid of the resistance problems common to most of the clinically used antibiotics, but further studies are needed to validate them in vivo as drug targets.

  9. The many forms of a pleomorphic bacterial pathogen – The developmental network of Legionella pneumophila

    Directory of Open Access Journals (Sweden)

    Peter eRobertson

    2014-12-01

    Full Text Available Legionella pneumophila is a natural intracellular bacterial parasite of free-living freshwater protozoa and an accidental human pathogen that causes Legionnaires’ disease. L. pneumophila differentiates, and does it in style. Recent experimental data on L. pneumophila’s differentiation point at the existence of a complex network that involves many developmental forms. We intend readers to: (i understand the biological relevance of L. pneumophila’s forms found in freshwater and their potential to transmit Legionnaires’ disease, and (ii learn that the common depiction of L. pneumophila’s differentiation as a biphasic developmental cycle that alternates between a replicative and a transmissive form is but an oversimplification of the actual process. Our specific objectives are to provide updates on the molecular factors that regulate L. pneumophila’s differentiation (section 2, and describe the developmental network of L. pneumophila (section 3, which for clarity’s sake we have dissected into five separate developmental cycles. Finally, since each developmental form seems to contribute differently to the human pathogenic process and the transmission of Legionnaires’ disease, readers are presented with a challenge to develop novel methods to detect the various L. pneumophila forms present in water (section 4, as a means to improve our assessment of risk and more effectively prevent legionellosis outbreaks.

  10. Deactivation of Legionella Pneumophila in municipal wastewater by ozone generated in arrays of microchannel plasmas

    Science.gov (United States)

    Dong, Shengkun; Li, Jun; Kim, Min-Hwan; Cho, Jinhoon; Park, Sung-Jin; Nguyen, Thanh H.; Eden, J. Gary

    2018-06-01

    A greater than four log10 reduction in the concentration of Legionella pneumophila in municipal wastewater has been achieved in 1 min with ozone produced by a microchannel plasma reactor. Requiring less than 22 W of electrical power, and ambient air as the feedstock gas, the microplasma ozone generator is robust and a promising alternative to conventional corona and dielectric barrier discharge (DBD) technologies. Contrary to previous studies, the Ct model for pathogen deactivation (i.e. rate proportional to the product of the available disinfectant concentration and the exposure duration) is found to be valid for L. pneumophila. Accordingly, wastewater-specific Ct equations have been developed to predict the deactivation of L. pneumophila in the secondary wastewater environment. Inactivation of this pathogen was found to be dependent on temperature only in the absence of wastewater organic matter (WOM). In the presence of WOM, pathogen deactivation is controlled by the disinfection contact time, initial ozone concentration (varied between 15 and 281 µg l‑1), and initial WOM loading. The data reported here will assist in the implementation of plasma ozone generators for L. pneumophila deactivation in cooling towers, point-of-use systems, and wastewater reclamation facilities.

  11. Structural and functional studies of a Cu+-ATPase from Legionella pneumophila

    DEFF Research Database (Denmark)

    Mattle, Daniel

    During his studies, Daniel Mattle explored the copper(I) export mechanism of a P-type Cu+ ATPase from Legionella pneumophila – a homologue to the human Cu+ ATPases. Cu+ ATPases are responsible for the homeostatic control of the physiological relevant – but toxic – copper(I) cations. To assess...

  12. Effect of Legionella pneumophila cytotoxic protease on human neutrophil and monocyte function

    DEFF Research Database (Denmark)

    Rechnitzer, C; Kharazmi, A

    1992-01-01

    The extracellular metalloprotease of Legionella pneumophila, also called tissue-destructive protease or major secretory protein, has been proposed as one of the virulence factors of this organism. Considering the decisive role played by the phagocytic cells in host defense against Legionella...

  13. Photoreactivation of UV-irradiated Legionella pneumophila and other Legionella species

    International Nuclear Information System (INIS)

    Knudson, G.B.

    1985-01-01

    Shortwave UV light was assessed as a feasible modality for the control of Legionnaires disease bacterium in water. The results of this study show that Legionella pneumophila and six other Legionella species are very sensitive to low doses of UV. However, all Legionella species tested effectively countered the germicidal effect of UV when subsequently exposed to photoreactivating light

  14. Widespread molecular detection of Legionella pneumophila Serogroup 1 in cold water taps across the United States

    Science.gov (United States)

    In the United States 3,522 cases of legionellosis were reported to the Center for Disease Control and Prevention in 2009. Of these reports, it is estimated that 84% are caused by the microorganism Legionella pneumophila Serogroup (Sg) 1. Legionella spp. have been isolated and r...

  15. Chlamydia trachomatis contains a protein similar to the Legionella pneumophila mip gene product

    DEFF Research Database (Denmark)

    Lundemose, AG; Birkelund, Svend; Fey, SJ

    1991-01-01

    A 27kDa Chlamydia trachomatis L2 protein was characterized by the use of monoclonal antibodies and by two-dimensional gel electrophoresis. The protein was shown to be located in the membrane of reticulate bodies as well as elementary bodies. Its synthesis could be detected from 10 hours post-infe...... potentiator (mip) gene of Legionella pneumophila....

  16. [Sequence-based typing of enviromental Legionella pneumophila isolates in Guangzhou].

    Science.gov (United States)

    Zhang, Ying; Qu, Pinghua; Zhang, Jian; Chen, Shouyi

    2011-03-01

    To characterize the genes of Legionella pneumophila isolated from different water source in Guangzhou from 2006 to 2009. To genotype the strains by using sequence-based typing (SBT) scheme. In total 44 L. pneumophila strains were identified by SBT with 7 diversifying genes of flaA, asd, mip, pilE, mompS, proA and neuA. Analysis of the amplicons sequence was taken in the European Working Group for Legionella Infections (EWGLI) international SBT database to obtain the allelic profiles and sequence types (STs). Serogroups were typed by latex agglutination test. Data from SBT revealed a high diversity among the strains and ST01 accounts for 30% (13/ 44). Fifteen new STs were discovered from 20 STs and 2 of them were newly assigned (ST887 and ST888) by EWGLI. SBT Phylogenetic tree was generated by SplitsTree and BURST programs. High diversity and specificity were observed of the L. pneumophila strains in Guangzhou. SBT is useful for L. pneumophila genomic study and epidemiological surveillance.

  17. Field inversion gel electrophoretic analysis of Legionella pneumophila strains associated with nosocomial legionellosis in children.

    Science.gov (United States)

    Green, M; Wald, E R; Dashefsky, B; Barbadora, K; Wadowsky, R M

    1996-01-01

    Two nosocomial cases of Legionnaires' disease occurred in children. Legionella pneumophila serogroup 1 was isolated from both patients and 30 of 39 plumbing system sites in the hospital. The patient and hospital environmental isolates yielded identical field inversion gel electrophoretic patterns which differed from patterns observed with epidemiologically unrelated strains.

  18. Satellite growth of Legionella pneumophila with an environmental isolate of Flavobacterium breve.

    Science.gov (United States)

    Wadowsky, R M; Yee, R B

    1983-12-01

    Legionella pneumophila serogroup 1 was observed to satellite around colonies of Flavobacterium breve on an L-cysteine-deficient medium which did not support growth of legionellae. Both isolates were recovered from the hot water tanks of hospitals. Ferric PPi stimulated satellite growth between 0.01 and 0.1%.

  19. Satellite growth of Legionella pneumophila with an environmental isolate of Flavobacterium breve.

    OpenAIRE

    Wadowsky, R M; Yee, R B

    1983-01-01

    Legionella pneumophila serogroup 1 was observed to satellite around colonies of Flavobacterium breve on an L-cysteine-deficient medium which did not support growth of legionellae. Both isolates were recovered from the hot water tanks of hospitals. Ferric PPi stimulated satellite growth between 0.01 and 0.1%.

  20. The Life Cycle of L. pneumophila: Cellular Differentiation Is Linked to Virulence and Metabolism

    Directory of Open Access Journals (Sweden)

    Giulia Oliva

    2018-01-01

    Full Text Available Legionella pneumophila is a gram-negative bacterium that inhabits freshwater ecosystems, where it is present in biofilm or as planktonic form. L. pneumophila is mainly found associated with protozoa, which serve as protection from hostile environments and as replication niche. If inhaled within aerosols, L. pneumophila is also able to infect and replicate in human alveolar macrophages, eventually causing the Legionnaires' disease. The transition between intracellular and extracellular environments triggers a differentiation program in which metabolic as well as morphogenetic changes occur. We here describe the current knowledge on how the different developmental states of this bacterium are regulated, with a particular emphasis on the stringent response activated during the transition from the replicative phase to the infectious phase and the metabolic features going in hand. We propose that the cellular differentiation of this intracellular pathogen is closely associated to key metabolic changes in the bacterium and the host cell, which together have a crucial role in the regulation of L. pneumophila virulence.

  1. Contamination of Tap Water with Pseudomonas aeruginosa, Legionella pneumophila, and Escherichia coli in Guilan, Iran

    Directory of Open Access Journals (Sweden)

    Masoumeh Ahmadi Jalali Moghadam

    2016-12-01

    Full Text Available Background: River and underground waters are main sources of tap water in Guilan, Iran. Overlandwastes move into rivers during periods of heavy or extended rain that is very common in the area.Pseudomonas aeruginosa, Legionella pneumophila, and Escherichia coli are main human pathogenswith water source. This study is designed to determine the load of these bacteria in main water suppliesof the area.Methods: Samples were collected directly into sterile containers, concentrated by centrifuge,inoculated in enrichment medium and incubated for 3-4 days. DNA was extracted by using commercialkit. Several rounds of PCR was performed to search P. aeroginosa, integron I, Metallo-β-lactamasesgene, L. pneumophila, mip gene, and E. coli.Results: About 92.0% of the samples showed bacterial contamination as revealed by PCR with primersof 16S rRNAgene, 9.5% of the samples had L. pneumophila, and 11,1% had Pseudomonas aeruginosa,but Escherichia coli was not detected. We found the mip gene in 66.6% of the samples with L.pneumophila. Metallo-β-lactamasesgene was found in 11.1% of all samples. We also found Integrin 1in 28.5% of the samples with P. aeruginosa.Conclusion: This study indicates that in spite of chlorination, total bacterial contamination of potwaters in the area is high and contamination with L. pneumophila and P. aeroginosa is considerable. Itmight be related to the biofilm formation and the growth of water microflora. It seems that free residualchlorine is ineffective. We suggest a more effective decontamination procedure based on moderntechnology.

  2. Legionella pneumophila: risk assessment and strategy for the prevention and control of nosocomial infections

    Directory of Open Access Journals (Sweden)

    Salvo Torrisi

    2012-06-01

    Full Text Available The term “Legionellosis” includes all forms of disease caused by microorganisms of the genus Legionella; it may manifest as a flu-like shape (Pontiac fever, or with severe pneumonia with high mortality (Legionnaires Disease. The causative agent was Legionella pneumophila in the literature although other strains of the genus Legionella are classified as pathogens, mode of transmission is through inhalation of aerosol particles produced by hot water or air conditioning systems: for this reason in community settings and nosocomial L. pneumophila represents a serious public health problem. In the light of epidemiological data since the year 2000 the Italian State has issued a series of provisions laws concerning the prevention and control of nosocomial Legionellosis environment and community.The present work aims to evaluate the presence of Legionella species and L. pneumophila comparing the different approaches proposed by the Guidelines of the regions of Lombardy and Piedmont in terms of assessment and prevention of risk “Legionellosis” in the field of nosocomial infection. The analytical methods used are those provided by the Regional Guidelines: the official method in the second CSR April 4 Method 2000 and UNI EN ISO 11731-1: 2008. Checks have been performed on equipment for the comparison of cold water, hot water and air conditioning in nursing homes, retirement homes and hospitals.The results obtained show that the method CSR April 4, 2000 restricts the search to L. pneumophila permitting, than the method EN ISO 11731-1: 2008, to carry out a risk assessment well targeted to the actual pathogen.The culture method for the detection of L. pneumophila allows you to not only prevention, but also to implement a series of targeted interventions following the directions of the legislation.

  3. Genome-scale identification of Legionella pneumophila effectors using a machine learning approach.

    Directory of Open Access Journals (Sweden)

    David Burstein

    2009-07-01

    Full Text Available A large number of highly pathogenic bacteria utilize secretion systems to translocate effector proteins into host cells. Using these effectors, the bacteria subvert host cell processes during infection. Legionella pneumophila translocates effectors via the Icm/Dot type-IV secretion system and to date, approximately 100 effectors have been identified by various experimental and computational techniques. Effector identification is a critical first step towards the understanding of the pathogenesis system in L. pneumophila as well as in other bacterial pathogens. Here, we formulate the task of effector identification as a classification problem: each L. pneumophila open reading frame (ORF was classified as either effector or not. We computationally defined a set of features that best distinguish effectors from non-effectors. These features cover a wide range of characteristics including taxonomical dispersion, regulatory data, genomic organization, similarity to eukaryotic proteomes and more. Machine learning algorithms utilizing these features were then applied to classify all the ORFs within the L. pneumophila genome. Using this approach we were able to predict and experimentally validate 40 new effectors, reaching a success rate of above 90%. Increasing the number of validated effectors to around 140, we were able to gain novel insights into their characteristics. Effectors were found to have low G+C content, supporting the hypothesis that a large number of effectors originate via horizontal gene transfer, probably from their protozoan host. In addition, effectors were found to cluster in specific genomic regions. Finally, we were able to provide a novel description of the C-terminal translocation signal required for effector translocation by the Icm/Dot secretion system. To conclude, we have discovered 40 novel L. pneumophila effectors, predicted over a hundred additional highly probable effectors, and shown the applicability of machine

  4. Spatial distribution of Legionella pneumophila MLVA-genotypes in a drinking water system.

    Science.gov (United States)

    Rodríguez-Martínez, Sarah; Sharaby, Yehonatan; Pecellín, Marina; Brettar, Ingrid; Höfle, Manfred; Halpern, Malka

    2015-06-15

    Bacteria of the genus Legionella cause water-based infections, resulting in severe pneumonia. To improve our knowledge about Legionella spp. ecology, its prevalence and its relationships with environmental factors were studied. Seasonal samples were taken from both water and biofilm at seven sampling points of a small drinking water distribution system in Israel. Representative isolates were obtained from each sample and identified to the species level. Legionella pneumophila was further determined to the serotype and genotype level. High resolution genotyping of L. pneumophila isolates was achieved by Multiple-Locus Variable number of tandem repeat Analysis (MLVA). Within the studied water system, Legionella plate counts were higher in summer and highly variable even between adjacent sampling points. Legionella was present in six out of the seven selected sampling points, with counts ranging from 1.0 × 10(1) to 5.8 × 10(3) cfu/l. Water counts were significantly higher in points where Legionella was present in biofilms. The main fraction of the isolated Legionella was L. pneumophila serogroup 1. Serogroup 3 and Legionella sainthelensis were also isolated. Legionella counts were positively correlated with heterotrophic plate counts at 37 °C and negatively correlated with chlorine. Five MLVA-genotypes of L. pneumophila were identified at different buildings of the sampled area. The presence of a specific genotype, "MLVA-genotype 4", consistently co-occurred with high Legionella counts and seemed to "trigger" high Legionella counts in cold water. Our hypothesis is that both the presence of L. pneumophila in biofilm and the presence of specific genotypes, may indicate and/or even lead to high Legionella concentration in water. This observation deserves further studies in a broad range of drinking water systems to assess its potential for general use in drinking water monitoring and management. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Interaction of legionella pneumophila and helicobacter pylori with bacterial species isolated from drinking water biofilms

    Directory of Open Access Journals (Sweden)

    Azevedo Nuno F

    2011-03-01

    Full Text Available Abstract Background It is well established that Legionella pneumophila is a waterborne pathogen; by contrast, the mode of Helicobacter pylori transmission remains unknown but water seems to play an important role. This work aims to study the influence of five microorganisms isolated from drinking water biofilms on the survival and integration of both of these pathogens into biofilms. Results Firstly, both pathogens were studied for auto- and co-aggregation with the species isolated from drinking water; subsequently the formation of mono and dual-species biofilms by L. pneumophila or H. pylori with the same microorganisms was investigated. Neither auto- nor co-aggregation was observed between the microorganisms tested. For biofilm studies, sessile cells were quantified in terms of total cells by SYTO 9 staining, viable L. pneumophila or H. pylori cells were quantified using 16 S rRNA-specific peptide nucleic acid (PNA probes and cultivable cells by standard culture techniques. Acidovorax sp. and Sphingomonas sp. appeared to have an antagonistic effect on L. pneumophila cultivability but not on the viability (as assessed by rRNA content using the PNA probe, possibly leading to the formation of viable but noncultivable (VBNC cells, whereas Mycobacterium chelonae increased the cultivability of this pathogen. The results obtained for H. pylori showed that M. chelonae and Sphingomonas sp. help this pathogen to maintain cultivability for at least 24 hours. Conclusions It appears that M. chelonae may have an important role in the survival of both pathogens in drinking water. This work also suggests that the presence of some microorganisms can decrease the cultivability of L. pneumophila but not the viability which indicates that the presence of autochthonous microorganisms can lead to misleading results when the safety of water is assessed by cultivable methods alone.

  6. Prevalence of Infection-Competent Serogroup 6 Legionella pneumophila within Premise Plumbing in Southeast Michigan

    Directory of Open Access Journals (Sweden)

    Brenda G. Byrne

    2018-02-01

    Full Text Available Coinciding with major changes to its municipal water system, Flint, MI, endured Legionnaires’ disease outbreaks in 2014 and 2015. By sampling premise plumbing in Flint in the fall of 2016, we found that 12% of homes harbored legionellae, a frequency similar to that in residences in neighboring areas. To evaluate the genetic diversity of Legionella pneumophila in Southeast Michigan, we determined the sequence type (ST and serogroup (SG of the 18 residential isolates from Flint and Detroit, MI, and the 33 clinical isolates submitted by hospitals in three area counties in 2013 to 2016. Common to one environmental and four clinical samples were strains of L. pneumophila SG1 and ST1, the most prevalent ST worldwide. Among the Flint premise plumbing isolates, 14 of 16 strains were of ST367 and ST461, two closely related SG6 strain types isolated previously from patients and corresponding environmental samples. Each of the representative SG1 clinical strains and SG6 environmental isolates from Southeast Michigan infected and survived within macrophage cultures at least as well as a virulent laboratory strain, as judged by microscopy and by enumerating CFU. Likewise, 72 h after infection, the yield of viable-cell counts increased >100-fold for each of the representative SG1 clinical isolates, Flint premise plumbing SG6 ST367 and -461 isolates, and two Detroit residential isolates. We verified by immunostaining that SG1-specific antibody does not cross-react with the SG6 L. pneumophila environmental strains. Because the widely used urinary antigen diagnostic test does not readily detect non-SG1 L. pneumophila, Legionnaires’ disease caused by SG6 L. pneumophila is likely underreported worldwide.

  7. A comparison of assays measuring the viability of Legionella pneumophila after treatment with copper and silver ions

    Science.gov (United States)

    Background: The relatively high prevalence of Legionella pneumophila in premise plumbing systems has been widely reported. Published reports indicate Legionella has a comparatively high resistance to chlorine and moreover has the ability to grow in phagocytic amoeba which could p...

  8. Preferential colonization and release of Legionella pneumophila from mature drinking water biofilms grown on copper versus unplasticized polyvinylchloride coupons

    Science.gov (United States)

    Legionella persistence and amplification in premise drinking water systems is a known contributor to legionellosis outbreaks, especially in the presence of suitable eukaryotic hosts. Here we examined Legionella pneumophila behavior within drinking water biofilms grown on copper ...

  9. Antibody-modified iron oxide nanoparticles for efficient magnetic isolation and flow cytometric determination of L. pneumophila

    International Nuclear Information System (INIS)

    Bloemen, Maarten; Verbiest, Thierry; Denis, Carla; Meester, Luc De; Peeters, Miet; Gils, Ann; Geukens, Nick

    2015-01-01

    We report on the design of superparamagnetic nanoparticles capable of selectively isolating targeted bacteria (Legionella pneumophila, serogroup 1) from aqueous solutions. The surface of magnetite nanoparticles (NP) was functionalized with a heterobifunctional poly(ethylene glycol) ligand containing reactive groups for covalent coupling of polyclonal antibodies against L. pneumophila. These bioconjugates were used to label and magnetically isolate L. pneumophila. Flow cytometry revealed high separation and efficiency in this regard. The strain specificity and efficiency of the magnetic NP was tested with recombinant strains of E. coli (expressing the red fluorescent protein) and L. pneumophila (expressing the green fluorescent protein). The detection limit of the method (by flow cytometry) is 10 4 cells∙mL -1 . The results indicate that the new multifunctional NPs are capable of selectively attracting pathogens from a complex mixture and with high efficiency. This, conceivably, paves the way to pre-concentration protocols for numerous other pathogens. (author)

  10. Transcriptional down-regulation and rRNA cleavage in Dictyostelium discoideum mitochondria during Legionella pneumophila infection.

    Directory of Open Access Journals (Sweden)

    Chenyu Zhang

    2009-05-01

    Full Text Available Bacterial pathogens employ a variety of survival strategies when they invade eukaryotic cells. The amoeba Dictyostelium discoideum is used as a model host to study the pathogenic mechanisms that Legionella pneumophila, the causative agent of Legionnaire's disease, uses to kill eukaryotic cells. Here we show that the infection of D. discoideum by L. pneumophila results in a decrease in mitochondrial messenger RNAs, beginning more than 8 hours prior to detectable host cell death. These changes can be mimicked by hydrogen peroxide treatment, but not by other cytotoxic agents. The mitochondrial large subunit ribosomal RNA (LSU rRNA is also cleaved at three specific sites during the course of infection. Two LSU rRNA fragments appear first, followed by smaller fragments produced by additional cleavage events. The initial LSU rRNA cleavage site is predicted to be on the surface of the large subunit of the mitochondrial ribosome, while two secondary sites map to the predicted interface with the small subunit. No LSU rRNA cleavage was observed after exposure of D. discoideum to hydrogen peroxide, or other cytotoxic chemicals that kill cells in a variety of ways. Functional L. pneumophila type II and type IV secretion systems are required for the cleavage, establishing a correlation between the pathogenesis of L. pneumophila and D. discoideum LSU rRNA destruction. LSU rRNA cleavage was not observed in L. pneumophila infections of Acanthamoeba castellanii or human U937 cells, suggesting that L. pneumophila uses distinct mechanisms to interrupt metabolism in different hosts. Thus, L. pneumophila infection of D. discoideum results in dramatic decrease of mitochondrial RNAs, and in the specific cleavage of mitochondrial rRNA. The predicted location of the cleavage sites on the mitochondrial ribosome suggests that rRNA destruction is initiated by a specific sequence of events. These findings suggest that L. pneumophila specifically disrupts mitochondrial

  11. Free-living protozoa in drinking water supplies: community composition and role as hosts for Legionella pneumophila

    OpenAIRE

    Valster, R.M.

    2011-01-01

    Free-living protozoa in drinking water supplies: community composition and role as hosts for Legionella pneumophila Free-living protozoa, which feed on bacteria, play an important role in the communities of microorganisms and invertebrates in drinking water supplies and in (warm) tap water installations. Several bacteria, including opportunistic human pathogens such as Legionella pneumophila, are able to survive and replicate within protozoan hosts, and certain free-living protozoa are opp...

  12. A Legionella pneumophila effector protein encoded in a region of genomic plasticity binds to Dot/Icm-modified vacuoles.

    Directory of Open Access Journals (Sweden)

    Shira Ninio

    2009-01-01

    Full Text Available Legionella pneumophila is an opportunistic pathogen that can cause a severe pneumonia called Legionnaires' disease. In the environment, L. pneumophila is found in fresh water reservoirs in a large spectrum of environmental conditions, where the bacteria are able to replicate within a variety of protozoan hosts. To survive within eukaryotic cells, L. pneumophila require a type IV secretion system, designated Dot/Icm, that delivers bacterial effector proteins into the host cell cytoplasm. In recent years, a number of Dot/Icm substrate proteins have been identified; however, the function of most of these proteins remains unknown, and it is unclear why the bacterium maintains such a large repertoire of effectors to promote its survival. Here we investigate a region of the L. pneumophila chromosome that displays a high degree of plasticity among four sequenced L. pneumophila strains. Analysis of GC content suggests that several genes encoded in this region were acquired through horizontal gene transfer. Protein translocation studies establish that this region of genomic plasticity encodes for multiple Dot/Icm effectors. Ectopic expression studies in mammalian cells indicate that one of these substrates, a protein called PieA, has unique effector activities. PieA is an effector that can alter lysosome morphology and associates specifically with vacuoles that support L. pneumophila replication. It was determined that the association of PieA with vacuoles containing L. pneumophila requires modifications to the vacuole mediated by other Dot/Icm effectors. Thus, the localization properties of PieA reveal that the Dot/Icm system has the ability to spatially and temporally control the association of an effector with vacuoles containing L. pneumophila through activities mediated by other effector proteins.

  13. Differences in Virulence Between Legionella pneumophila Isolates From Human and Non-human Sources Determined in Galleria mellonella Infection Model

    Directory of Open Access Journals (Sweden)

    Patrícia S. Sousa

    2018-04-01

    Full Text Available Legionella pneumophila is a ubiquitous bacterium in freshwater environments and in many man-made water systems capable of inducing pneumonia in humans. Despite its ubiquitous character most studies on L. pneumophila virulence focused on clinical strains and isolates from man-made environments, so little is known about the nature and extent of virulence variation in strains isolated from natural environments. It has been established that clinical isolates are less diverse than man-made and natural environmental strains, suggesting that only a subset of environmental isolates is specially adapted to infect humans. In this work we intended to determine if unrelated L. pneumophila strains, isolated from different environments and with distinct virulence-related genetic backgrounds, displayed differences in virulence, using the Wax Moth Galleria mellonella infection model. We found that all tested strains were pathogenic in G. mellonella, regardless of their origin. Indeed, a panoply of virulence-related phenotypes was observed sustaining the existence of significant differences on the ability of L. pneumophila strains to induce disease. Taken together our results suggest that the occurrence of human infection is not related with the increased capability of some strains to induce disease since we also found a concentration threshold above which L. pneumophila strains are equally able to cause disease. In addition, no link could be established between the sequence-type (ST and L. pneumophila pathogenicity. We envision that in man-made water distribution systems environmental filtering selection and biotic competition acts structuring L. pneumophila populations by selecting more resilient and adapted strains that can rise to high concentration if no control measures are implemented. Therefore, public health strategies based on the sequence based typing (STB scheme analysis should take into account that the major disease-associated clones of L

  14. Rapid on-site monitoring of Legionella pneumophila in cooling tower water using a portable microfluidic system.

    Science.gov (United States)

    Yamaguchi, Nobuyasu; Tokunaga, Yusuke; Goto, Satoko; Fujii, Yudai; Banno, Fumiya; Edagawa, Akiko

    2017-06-08

    Legionnaires' disease, predominantly caused by the bacterium Legionella pneumophila, has increased in prevalence worldwide. The most common mode of transmission of Legionella is inhalation of contaminated aerosols, such as those generated by cooling towers. Simple, rapid and accurate methods to enumerate L. pneumophila are required to prevent the spread of this organism. Here, we applied a microfluidic device for on-chip fluorescent staining and semi-automated counting of L. pneumophila in cooling tower water. We also constructed a portable system for rapid on-site monitoring and used it to enumerate target bacterial cells rapidly flowing in the microchannel. A fluorescently-labelled polyclonal antibody was used for the selective detection of L. pneumophila serogroup 1 in the samples. The counts of L. pneumophila in cooling tower water obtained using the system and fluorescence microscopy were similar. The detection limit of the system was 10 4  cells/ml, but lower numbers of L. pneumophila cells (10 1 to 10 3  cells/ml) could be detected following concentration of 0.5-3 L of the water sample by filtration. Our technique is rapid to perform (1.5 h), semi-automated (on-chip staining and counting), and portable for on-site measurement, and it may therefore be effective in the initial screening of Legionella contamination in freshwater.

  15. Hacking the art of exploitation

    CERN Document Server

    Erickson, Jon

    2003-01-01

    A comprehensive introduction to the techniques of exploitation and creative problem-solving methods commonly referred to as "hacking," Hacking: The Art of Exploitation is for both technical and non-technical people who are interested in computer security. It shows how hackers exploit programs and write exploits, instead of just how to run other people's exploits. Unlike many so-called hacking books, this book explains the technical aspects of hacking, including stack based overflows, heap based overflows, string exploits, return-into-libc, shellcode, and cryptographic attacks on 802.11b.

  16. Nanostructured Basaltfiberconcrete Exploitational Characteristics

    Science.gov (United States)

    Saraykina, K. A.; Shamanov, V. A.

    2017-11-01

    The article demonstrates that the mass use of basalt fiber concrete (BFC) is constrained by insufficient study of their durability and serviceability in a variety of environments. This research is aimed at the study of the basalt fiber corrosion processes in the cement stone of BFC, the control of the new products structure formation in order to protect the reinforcing fiber from alkaline destruction and thereby improve the exploitational characteristics of the composite. The research result revealed that the modification of basaltfiber concrete by the dispersion of MWNTs contributes to the directional formation of new products in the cement matrix. The HAM additive in basaltfiberconcrete provides for the binding of portlandite to low-basic calcium hydroaluminosilicates, thus reducing the aggressive effect of the cement environment on the reinforcing fibers properties. The complex modification of BFC with nanostructured additives provides for an increase in its durability and exploitational properties (strength, frost resistance and water resistance) due to basalt fiber protection from alkali corrosion on account of the compacting of the contact zone “basalt fiber - cement stone” and designing of the new products structure and morphology of cement matrix over the fiber surface.

  17. Crucial Role of Legionella pneumophila TolC in the Inhibition of Cellular Trafficking in the Protistan Host Paramecium tetraurelia.

    Science.gov (United States)

    Nishida, Takashi; Hara, Naho; Watanabe, Kenta; Shimizu, Takashi; Fujishima, Masahiro; Watarai, Masahisa

    2018-01-01

    Legionella pneumophila is a facultative intracellular Gram-negative bacterium, which is a major causative agent of Legionnaires' disease. In the environment, this bacterium survives in free-living protists such as amoebae and Tetrahymena . The association of L. pneumophila and protists leads to the replication and spread of this bacterium. Thus, from a public health perspective, their association can enhance the risk of L. pneumophila infection for humans. Paramecium spp. are candidates of natural hosts of L. pneumophila , but their detailed relationships remain unclear. In the present study, we used an environmental strain, L. pneumophila Ofk308 (Ofk308) and Paramecium tetraurelia st110-1a to reveal the relationship between L. pneumophila and Paramecium spp. Ofk308 was cytotoxic to P. tetraurelia in an infection-dependent manner. We focused on TolC, a component of the type I secretion system, which is a virulence factor of L. pneumophila toward protists and found that cytotoxicity was dependent on TolC but not on other T1SS components. Further, the number of bacteria in P. tetraurelia was not associated with cytotoxicity and TolC was not involved in the mechanism of resistance against the digestion of P. tetraurelia in Ofk308. We used a LysoTracker to evaluate the maturation process of P. tetraurelia phagosomes containing Ofk308. We found that there was no difference between Ofk308 and the tolC -deletion mutant. To assess the phagocytic activity of P. tetraurelia , Texas Red-conjugated dextran-uptake assays were performed. Ofk308 inhibited phagosome formation by P. tetraurelia through a TolC-dependent mechanism. Further, we evaluated the excretion of Legionella -containing vacuoles from P. tetraurelia . We found that P. tetraurelia failed to excrete undigested Ofk308 and that Ofk308 remained within cells through a TolC-dependent mechanism. Our results suggest that TolC is essential for L. pneumophila to remain within Paramecium cells and to show cytotoxicity

  18. Crucial Role of Legionella pneumophila TolC in the Inhibition of Cellular Trafficking in the Protistan Host Paramecium tetraurelia

    Directory of Open Access Journals (Sweden)

    Takashi Nishida

    2018-04-01

    Full Text Available Legionella pneumophila is a facultative intracellular Gram-negative bacterium, which is a major causative agent of Legionnaires’ disease. In the environment, this bacterium survives in free-living protists such as amoebae and Tetrahymena. The association of L. pneumophila and protists leads to the replication and spread of this bacterium. Thus, from a public health perspective, their association can enhance the risk of L. pneumophila infection for humans. Paramecium spp. are candidates of natural hosts of L. pneumophila, but their detailed relationships remain unclear. In the present study, we used an environmental strain, L. pneumophila Ofk308 (Ofk308 and Paramecium tetraurelia st110-1a to reveal the relationship between L. pneumophila and Paramecium spp. Ofk308 was cytotoxic to P. tetraurelia in an infection-dependent manner. We focused on TolC, a component of the type I secretion system, which is a virulence factor of L. pneumophila toward protists and found that cytotoxicity was dependent on TolC but not on other T1SS components. Further, the number of bacteria in P. tetraurelia was not associated with cytotoxicity and TolC was not involved in the mechanism of resistance against the digestion of P. tetraurelia in Ofk308. We used a LysoTracker to evaluate the maturation process of P. tetraurelia phagosomes containing Ofk308. We found that there was no difference between Ofk308 and the tolC-deletion mutant. To assess the phagocytic activity of P. tetraurelia, Texas Red-conjugated dextran-uptake assays were performed. Ofk308 inhibited phagosome formation by P. tetraurelia through a TolC-dependent mechanism. Further, we evaluated the excretion of Legionella-containing vacuoles from P. tetraurelia. We found that P. tetraurelia failed to excrete undigested Ofk308 and that Ofk308 remained within cells through a TolC-dependent mechanism. Our results suggest that TolC is essential for L. pneumophila to remain within Paramecium cells and to show

  19. DupA: a key regulator of the amoebal MAP kinase response to Legionella pneumophila

    Science.gov (United States)

    Li, Zhiru; Dugan, Aisling S.; Bloomfield, Gareth; Skelton, Jason; Ivens, Alasdair; Losick, Vicki; Isberg, Ralph R.

    2009-01-01

    SUMMARY The dupA gene, encoding a putative tyrosine kinase/dual specificity phosphatase (Dusp), was identified in a screen for Dictyostelium discoideum mutants altered in supporting Legionella pneumophila intracellular replication. The absence of dupA resulted in hyperphosphorylation of ERK1, consistent with the loss of a phosphatase activity, as well as degradation of ERK2. ERK1 hyperphosphorylation mimicked the response of this protein after bacterial challenge of wild type amoebae. Similar to Dusps in higher eukaryotic cells, the amoebal dupA gene was induced after bacterial contact, indicating a response of Dusps that is conserved from amoebae to mammals. A large set of genes was misregulated in the dupA− mutant that largely overlaps with genes responding to L. pneumophila infection. Some of the amoebal genes appear to be involved in a response similar to innate immunity in higher eukaryotes, indicating there was misregulation of a conserved response to bacteria. PMID:19748467

  20. Monitoring of Legionella pneumophila viability after chlorine dioxide treatment using flow cytometry.

    Science.gov (United States)

    Mustapha, Pascale; Epalle, Thibaut; Allegra, Séverine; Girardot, Françoise; Garraud, Olivier; Riffard, Serge

    2015-04-01

    The viability of three Legionella pneumophila strains was monitored after chlorine dioxide (ClO2) treatment using a flow cytometric assay. Suspensions of L. pneumophila cells were submitted to increasing concentrations of ClO2. Culturable cells were still detected when using 4 mg/L, but could no longer be detected after exposure to 6 mg/L of ClO2, although viable but not culturable (VBNC) cells were found after exposure to 4-5 mg/L of ClO2. When testing whether these VBNC were infective, two of the strains were resuscitated after co-culture with Acanthamoeba polyphaga, but neither of them could infect macrophage-like cells. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  1. Prevalence of Infection-Competent Serogroup 6 Legionella pneumophila within Premise Plumbing in Southeast Michigan.

    Science.gov (United States)

    Byrne, Brenda G; McColm, Sarah; McElmurry, Shawn P; Kilgore, Paul E; Sobeck, Joanne; Sadler, Rick; Love, Nancy G; Swanson, Michele S

    2018-02-06

    Coinciding with major changes to its municipal water system, Flint, MI, endured Legionnaires' disease outbreaks in 2014 and 2015. By sampling premise plumbing in Flint in the fall of 2016, we found that 12% of homes harbored legionellae, a frequency similar to that in residences in neighboring areas. To evaluate the genetic diversity of Legionella pneumophila in Southeast Michigan, we determined the sequence type (ST) and serogroup (SG) of the 18 residential isolates from Flint and Detroit, MI, and the 33 clinical isolates submitted by hospitals in three area counties in 2013 to 2016. Common to one environmental and four clinical samples were strains of L. pneumophila SG1 and ST1, the most prevalent ST worldwide. Among the Flint premise plumbing isolates, 14 of 16 strains were of ST367 and ST461, two closely related SG6 strain types isolated previously from patients and corresponding environmental samples. Each of the representative SG1 clinical strains and SG6 environmental isolates from Southeast Michigan infected and survived within macrophage cultures at least as well as a virulent laboratory strain, as judged by microscopy and by enumerating CFU. Likewise, 72 h after infection, the yield of viable-cell counts increased >100-fold for each of the representative SG1 clinical isolates, Flint premise plumbing SG6 ST367 and -461 isolates, and two Detroit residential isolates. We verified by immunostaining that SG1-specific antibody does not cross-react with the SG6 L. pneumophila environmental strains. Because the widely used urinary antigen diagnostic test does not readily detect non-SG1 L. pneumophila , Legionnaires' disease caused by SG6 L. pneumophila is likely underreported worldwide. IMPORTANCE L. pneumophila is the leading cause of disease outbreaks associated with drinking water in the United States. Compared to what is known of the established risks of colonization within hospitals and hotels, relatively little is known about residential exposure to

  2. Exploitation by Economic Necessity

    Directory of Open Access Journals (Sweden)

    Kristian F. Braekkan

    2015-10-01

    Full Text Available This study develops and tests a model that proposes economic necessity moderates the relationship between psychological contract violations (PCVs and organizational commitment and trust in the employing organization among non-unionized manufacturing workers (N = 226. Moderated regression analyses revealed that there was a significant interaction between PCV and economic necessity in predicting both outcomes. Specifically, the findings indicated that individuals experiencing high PCV and high economic necessity did not decrease their organizational commitment like their counterparts who endorsed lower economic necessity. They did, however, experience significantly decreased trust in their employer. The findings suggest that individuals who are forced to sell their labor power and obtain what they need through the market are more likely to continue to be exploited by their employer, as they have no other options than to continue the relationship. The importance of the findings is discussed, and recommendations for future research are provided.

  3. Exploitative Learning by Exporting

    DEFF Research Database (Denmark)

    Golovko, Elena; Lopes Bento, Cindy; Sofka, Wolfgang

    Decisions on entering foreign markets are among the most challenging but also potentially rewarding strategy choices managers can make. In this study, we examine the effect of export entry on the firm investment decisions in two activities associated with learning about new technologies...... and learning about new markets ? R&D investments and marketing investments, in search of novel insights into the content and process underlying learning by exporting. We draw from organizational learning theory for predicting changes in both R&D and marketing investment patterns that accompany firm entry......, it is predominantly the marketing-related investment decisions associated with starting to export that lead to increases in firm productivity. We conclude that learning-by-exporting might be more properly characterized as ?learning about and exploiting new markets? rather than ?learning about new technologies...

  4. Origin and prevention of infection with Legionella pneumophila through cooling towers and evaporative cooling towers

    International Nuclear Information System (INIS)

    Schulze-Roebbecke, R.

    1994-01-01

    Evaporative cooling towers and industrial ventilator cooling towers have repeatedly been described as the origin of Legionnaires' disease. This article describes the design and function of cooling towers and evaporative cooling towers, sums up knowledge on the colonization of such systems with Legionella pneumophila, and describes conditions permitting the transmission of Legionella. Furthermore, design, maintenance, cleaning and disinfection measures are indicated which are believed to reduce the risk of infection through industrial and evaporative cooling towers. (orig.) [de

  5. Promotion and Rescue of Intracellular Brucella neotomae Replication during Coinfection with Legionella pneumophila.

    Science.gov (United States)

    Kang, Yoon-Suk; Kirby, James E

    2017-05-01

    We established a new Brucella neotomae in vitro model system for study of type IV secretion system-dependent (T4SS) pathogenesis in the Brucella genus. Importantly, B. neotomae is a rodent pathogen, and unlike B. abortus , B. melitensis , and B. suis , B. neotomae has not been observed to infect humans. It therefore can be handled more facilely using biosafety level 2 practices. More particularly, using a series of novel fluorescent protein and lux operon reporter systems to differentially label pathogens and track intracellular replication, we confirmed T4SS-dependent intracellular growth of B. neotomae in macrophage cell lines. Furthermore, B. neotomae exhibited early endosomal (LAMP-1) and late endoplasmic reticulum (calreticulin)-associated phagosome maturation. These findings recapitulate prior observations for human-pathogenic Brucella spp. In addition, during coinfection experiments with Legionella pneumophila , we found that defective intracellular replication of a B. neotomae T4SS virB4 mutant was rescued and baseline levels of intracellular replication of wild-type B. neotomae were significantly stimulated by coinfection with wild-type but not T4SS mutant L. pneumophila Using confocal microscopy, it was determined that intracellular colocalization of B. neotomae and L. pneumophila was required for rescue and that colocalization came at a cost to L. pneumophila fitness. These findings were not completely expected based on known temporal and qualitative differences in the intracellular life cycles of these two pathogens. Taken together, we have developed a new system for studying in vitro Brucella pathogenesis and found a remarkable T4SS-dependent interplay between Brucella and Legionella during macrophage coinfection. Copyright © 2017 American Society for Microbiology.

  6. In Vitro Response of Guinea Pig Peritoneal Macrophages to Legionella pneumophila

    Science.gov (United States)

    1981-03-01

    In Vitro Responlse of Guinea Pig Peritoneal Macrophages to Legionella pneumophila It. A. KISIIIMi~O~’ .1. Ii.,W11ITE, F. G. SIREY, V. (U.1 Mc(GANN, R...Tlhe inter- act ion between L. lincumnophila andl( peritoneal macrophages front normial guinea pigs or front animials that had survived infection was...roagglujtiniat titer) guinea pig serum to The purp~ose of this study "as to investigate contain approximately 108 organisms per ml. the phagocytic and

  7. Discovery of Ubiquitin Deamidases in the Pathogenic Arsenal of Legionella pneumophila

    Directory of Open Access Journals (Sweden)

    Dylan Valleau

    2018-04-01

    Full Text Available Summary: Legionella pneumophila translocates the largest known arsenal of over 330 pathogenic factors, called “effectors,” into host cells during infection, enabling L. pneumophila to establish a replicative niche inside diverse amebas and human macrophages. Here, we reveal that the L. pneumophila effectors MavC (Lpg2147 and MvcA (Lpg2148 are structural homologs of cycle inhibiting factor (Cif effectors and that the adjacent gene, lpg2149, produces a protein that directly inhibits their activity. In contrast to canonical Cifs, both MavC and MvcA contain an insertion domain and deamidate the residue Gln40 of ubiquitin but not Gln40 of NEDD8. MavC and MvcA are functionally diverse, with only MavC interacting with the human E2-conjugating enzyme UBE2N (Ubc13. MavC deamidates the UBE2N∼Ub conjugate, disrupting Lys63 ubiquitination and dampening NF-κB signaling. Combined, our data reveal a molecular mechanism of host manipulation by pathogenic bacteria and highlight the complex regulatory mechanisms integral to L. pneumophila’s pathogenic strategy. : Legionella pneumophila, possessing the largest known arsenal of effectors, continues to reveal unique approaches to host cell control. Valleau et al. decrypt the functions of a trio of effectors, discovering a pair of ubiquitin-specific deamidases, their regulation by a neighboring dual-specificity protein inhibitor, and a mechanism of NF-κB suppression. Keywords: pathogen-host interaction, ubiquitination, Legionella, UBE2N/Ubc13, NF-κB signaling, Type IV secretion system, effectors, metaeffector, cycle inhibiting factor

  8. Learning Metasploit exploitation and development

    CERN Document Server

    Balapure, Aditya

    2013-01-01

    A practical, hands-on tutorial with step-by-step instructions. The book will follow a smooth and easy-to-follow tutorial approach, covering the essentials and then showing the readers how to write more sophisticated exploits.This book targets exploit developers, vulnerability analysts and researchers, network administrators, and ethical hackers looking to gain advanced knowledge in exploitation development and identifying vulnerabilities. The primary goal is to take readers wishing to get into more advanced exploitation discovery and reaching the next level.Prior experience exploiting basic st

  9. Development of a new CARD-FISH protocol for quantification of Legionella pneumophila and its application in two hospital cooling towers.

    Science.gov (United States)

    Kirschner, A K T; Rameder, A; Schrammel, B; Indra, A; Farnleitner, A H; Sommer, R

    2012-06-01

    Open cooling towers are frequent sources of infections with Legionella pneumophila. The gold standard for the detection of Leg. pneumophila is based on cultivation lasting up to 10 days and detecting only culturable cells. Alternative fluorescence in situ hybridization (FISH) protocols have been proposed, but they result in faint fluorescence signals and lack specificity because of cross-hybridization with other Legionella species. Our aim was thus to develop a new FISH protocol for rapid and specific detection of Leg. pneumophila in water samples. A novel catalysed reporter deposition FISH (CARD-FISH) protocol for the detection of Leg. pneumophila was developed, which significantly enhanced signal intensity as well as specificity of the probe through the use of a novel competitor probe. The developed protocol was compared with the culture method for monitoring the seasonal development of culturable and nonculturable Leg. pneumophila in two hospital cooling tower systems. Seasonal fluctuations of Leg. pneumophila concentrations detected via CARD-FISH were related to the development of the total bacterial community in both cooling towers, with temperature and biocide as the main factors controlling this development. Our results clearly showed that the majority of the Leg. pneumophila cells were in a nonculturable state. Thus, detection of Leg. pneumophila with culture methods may underestimate the total numbers of Leg. pneumophila present. Rapid, sensitive and specific detection and quantification of Leg. pneumophila in water systems is prerequisite for reliable risk estimation. The new protocol significantly improves current methodology and can be used to monitor and screen for Leg. pneumophila concentrations in cooling towers or other water systems. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

  10. Roles of iron in the survival, growth, and pathogenesis of Legionella pneumophila

    International Nuclear Information System (INIS)

    Quinn, F.D.

    1985-01-01

    The essentially of iron for living cells has long been recognized, and the availability of host-iron has been proposed as a contributing factor to virulence in bacterial, fungal, and protozoan infections. The mechanism by which legionella pneumophila causes disease is unknown. Growth of fresh clinical or environmental isolates in pure culture requires 20 times more iron than is needed for most other bacteria. Thus, increased plasma iron levels may be needed for multiplication within human hosts. It was observed that: (1) this organism can be more readily deprived of iron by iron binding agents than all other bacteria studied, and this inhibition can be reversed by the addition of iron; (2) normal human blood serum kills L. pneumophila and the bactericidal action is decreased when complement is inactivated or enough iron to saturate serum transferrin is added to the system; (3) in assays with a radioactive isotope of iron ( 55 Fe), no specific iron sequestering system was detected; (4) in analysis of outer membrane proteins with 55 Fe, SDS-polyacrylamide gel electrophoresis, and autoradiography, no specific outer membrane proteins responsible for iron acquisition were observed; and (5) in assays for protease, iron does not stimulate production of extracellular proteases. These observations indicate that L. pneumophila has no specific iron uptake mechanism, but instead relies on passive diffusion and/or non-specific mechanisms to obtain its iron

  11. [Diversity of Legionella pneumophila in cooling towers: coculture kinetics and virulence studies].

    Science.gov (United States)

    Ragull, Sonia; García-Núñez, Marian; Pedro-Botet, María Luisa; Rey-Joly, Celestino; Sabria, Miquel

    2011-05-01

    Legionella pneumophila (L. pneumophila) was isolated from three cooling towers involved in three community outbreaks of Legionnaireś disease. Each cooling tower had two different chromosomal DNA subtypes. However, only one matched identically to the clinical strains. To try to understand why only one of the environmental strains caused clinical cases we investigated the intrinsic virulence of these strains. We selected six strains of L. pneumophila sg.1: two strains (A1 and B1) from cooling tower 1, two strains (A2 and B2) from tower 2 and two strains (A3 and B3) from tower 3. One of the two subtypes (A) exhibited the same chromosomal DNA subtype as the strains isolated from the patients in each outbreak and the other exhibited a different subtype. The replication within macrophages, the presence of lipopolysaccharide epitope recognized by MAb 3/1 and the growth kinetics in BCYE broth were investigated. Isolates were typed by pulsed field electrophoresis. The A strains did not have a higher virulence level, but were able to grow and survive better than strains B in BCYE broth. These results suggest that the strains better adapted to the environment will manage to displace the others and will be able to spread and infect humans. The adaptation to the environmental conditions could play an important role in the pathogenesis of the strains. Copyright © 2010 Elsevier España, S.L. All rights reserved.

  12. Virulence factor rtx in Legionella pneumophila, evidence suggesting it is a modular multifunctional protein

    Directory of Open Access Journals (Sweden)

    Pelaz Carmen

    2008-01-01

    Full Text Available Abstract Background The repeats in toxin (Rtx are an important pathogenicity factor involved in host cells invasion of Legionella pneumophila and other pathogenic bacteria. Its role in escaping the host immune system and cytotoxic activity is well known. Its repeated motives and modularity make Rtx a multifunctional factor in pathogenicity. Results The comparative analysis of rtx gene among 6 strains of L. pneumophila showed modularity in their structures. Among compared genomes, the N-terminal region of the protein presents highly dissimilar repeats with functionally similar domains. On the contrary, the C-terminal region is maintained with a fashionable modular configuration, which gives support to its proposed role in adhesion and pore formation. Despite the variability of rtx among the considered strains, the flanking genes are maintained in synteny and similarity. Conclusion In contrast to the extracellular bacteria Vibrio cholerae, in which the rtx gene is highly conserved and flanking genes have lost synteny and similarity, the gene region coding for the Rtx toxin in the intracellular pathogen L. pneumophila shows a rapid evolution. Changes in the rtx could play a role in pathogenicity. The interplay of the Rtx toxin with host membranes might lead to the evolution of new variants that are able to escape host cell defences.

  13. Detection of Legionella, L. pneumophila and Mycobacterium Avium Complex (MAC) along Potable Water Distribution Pipelines

    Science.gov (United States)

    Whiley, Harriet; Keegan, Alexandra; Fallowfield, Howard; Bentham, Richard

    2014-01-01

    Inhalation of potable water presents a potential route of exposure to opportunistic pathogens and hence warrants significant public health concern. This study used qPCR to detect opportunistic pathogens Legionella spp., L. pneumophila and MAC at multiple points along two potable water distribution pipelines. One used chlorine disinfection and the other chloramine disinfection. Samples were collected four times over the year to provide seasonal variation and the chlorine or chloramine residual was measured during collection. Legionella spp., L. pneumophila and MAC were detected in both distribution systems throughout the year and were all detected at a maximum concentration of 103 copies/mL in the chlorine disinfected system and 106, 103 and 104 copies/mL respectively in the chloramine disinfected system. The concentrations of these opportunistic pathogens were primarily controlled throughout the distribution network through the maintenance of disinfection residuals. At a dead-end and when the disinfection residual was not maintained significant (p < 0.05) increases in concentration were observed when compared to the concentration measured closest to the processing plant in the same pipeline and sampling period. Total coliforms were not present in any water sample collected. This study demonstrates the ability of Legionella spp., L. pneumophila and MAC to survive the potable water disinfection process and highlights the need for greater measures to control these organisms along the distribution pipeline and at point of use. PMID:25046636

  14. Detection of Legionella, L. pneumophila and Mycobacterium avium complex (MAC) along potable water distribution pipelines.

    Science.gov (United States)

    Whiley, Harriet; Keegan, Alexandra; Fallowfield, Howard; Bentham, Richard

    2014-07-18

    Inhalation of potable water presents a potential route of exposure to opportunistic pathogens and hence warrants significant public health concern. This study used qPCR to detect opportunistic pathogens Legionella spp., L. pneumophila and MAC at multiple points along two potable water distribution pipelines. One used chlorine disinfection and the other chloramine disinfection. Samples were collected four times over the year to provide seasonal variation and the chlorine or chloramine residual was measured during collection. Legionella spp., L. pneumophila and MAC were detected in both distribution systems throughout the year and were all detected at a maximum concentration of 103 copies/mL in the chlorine disinfected system and 106, 103 and 104 copies/mL respectively in the chloramine disinfected system. The concentrations of these opportunistic pathogens were primarily controlled throughout the distribution network through the maintenance of disinfection residuals. At a dead-end and when the disinfection residual was not maintained significant (p pipeline and sampling period. Total coliforms were not present in any water sample collected. This study demonstrates the ability of Legionella spp., L. pneumophila and MAC to survive the potable water disinfection process and highlights the need for greater measures to control these organisms along the distribution pipeline and at point of use.

  15. Travel-associated infections caused by unusual serogroups of Legionella pneumophila identified using Legionella BIOCHIP slides in Turkey and Iraq.

    Science.gov (United States)

    Kocazeybek, Bekir S; Yuksel, Pelin; Keskin, Dilek; Sheikh, Suhail; Habip, Zafer; Yavuzer, Serap Sahin; Caliskan, Reyhan; Altun, Yagız Meric; Kuskucu, Mert; Cengiz, Mahir; Dinc, Harika Oyku; Karakullukcu, Asiye; Ergin, Sevgi; Saribas, Suat; Yilmaz, Nail; Tokman, Hrisi Bahar

    2016-01-01

    Although Legionella pneumophila serogroup 1 is the common disease causing serogroup, rare serogroups can also may cause legionellosis. A 54-year-old male patient (index case) reported that he had been on a religious trip (for visiting, tomb of Ali, which is important for Shias) to Iraq with a large group (50 shia pilgrims from Kars city of Turkey) two weeks prior to admission. Due to civil war, the hotel where the patient stayed in Iraq lacked proper hygiene. A large number of people in the travel group were experiencing the same symptoms. Other five cases were 2 males (ages; 50, 45) and 3 females including the wife of the index case (ages; 50, 28, 27). The detection of L. pneumophila IgG and IgM was performed by anti-L. pneumophila Indirect Immunofluorescent IgM, IgG kit. Legionella 1 biochip/verification BIOCHIP slides were used for serogrouping in Euroimmun AG, Leubeck, Germany. In index case, L. pneumophila IgM was positive with a titer of 1/32 titer. IgG was negative with a 1/100 titer. Another case (28 year old female), had clinical symptoms identical to the index case. L. pneumophila IgM and IgG were positive with titers of 1/64 and 1/100, respectively. These two cases were diagnosed with Legionnaires' disease caused by L. pneumophila serogroup 12 (index case) and female (28-year-old) by serogroup 11. The other 4 cases were diagnosed with possible Pontiac fever caused by L. pneumophila serogroups 14 (wife of the index case), 4, and 6 whereas the serogroup of L. pneumophila detected in 27 years old female case could not be identified. A major limitation of this work is the absence of genotyping and the serogroup difference between index case and his wife who shared the same hotel. We suggest that this serogroup difference may be caused by (for men and women) sitting separately in Islamic rules. On the other hand, the movement of people in the context of mutual visits between countries or neighboring countries for tourism-related (i.e., for religious events

  16. A single Legionella pneumophila genotype in the freshwater system in a ship experiencing three separate outbreaks of legionellosis in 6 years

    Directory of Open Access Journals (Sweden)

    Catrine Ahlen

    2016-08-01

    Full Text Available Background: Recurrent legionella outbreaks at one and the same location are common. We have identified a single Legionella pneumophila genotype associated with recurrent Legionella outbreaks over 6 years. Methods: Field emergency surveys following Legionella outbreaks were performed on a vessel in 2008, 2009 and 2013. Water samples from both the distribution and technical parts of the potable water system were analyzed with respect to L. pneumophila [Real-Time PCR, cultivation, serotyping and genotyping (PFGE] and free-living amoebae, (FLA. Results: Legionella pneumophila serogroup 1 was present in the ship's potable water system during every outbreak. Genotyping of the 2008 survey material showed two separate PFGE genotypes while those in 2009 and 2013 demonstrated the presence of only one of the two genotypes. FLA with intracellular L. pneumophila of the same genotype were also detected. Analyses of the freshwater system on a ship following three separate Legionella outbreaks, for L. pneumophila and FLAs, revealed a single L. pneumophila genotype and FLA (Hartmanella. Conclusions: It is reasonable to assume that the L. pneumophila genotype detected in the freshwater system was the causal agent in the outbreaks onboard. Persistence of an apparently low-pathogenic L. pneumophila genotype and FLA in a potable water system represent a potential risk for recurrent outbreaks.

  17. Neutrophil and Alveolar Macrophage-Mediated Innate Immune Control of Legionella pneumophila Lung Infection via TNF and ROS.

    Directory of Open Access Journals (Sweden)

    Pascal Ziltener

    2016-04-01

    Full Text Available Legionella pneumophila is a facultative intracellular bacterium that lives in aquatic environments where it parasitizes amoeba. However, upon inhalation of contaminated aerosols it can infect and replicate in human alveolar macrophages, which can result in Legionnaires' disease, a severe form of pneumonia. Upon experimental airway infection of mice, L. pneumophila is rapidly controlled by innate immune mechanisms. Here we identified, on a cell-type specific level, the key innate effector functions responsible for rapid control of infection. In addition to the well-characterized NLRC4-NAIP5 flagellin recognition pathway, tumor necrosis factor (TNF and reactive oxygen species (ROS are also essential for effective innate immune control of L. pneumophila. While ROS are essential for the bactericidal activity of neutrophils, alveolar macrophages (AM rely on neutrophil and monocyte-derived TNF signaling via TNFR1 to restrict bacterial replication. This TNF-mediated antibacterial mechanism depends on the acidification of lysosomes and their fusion with L. pneumophila containing vacuoles (LCVs, as well as caspases with a minor contribution from cysteine-type cathepsins or calpains, and is independent of NLRC4, caspase-1, caspase-11 and NOX2. This study highlights the differential utilization of innate effector pathways to curtail intracellular bacterial replication in specific host cells upon L. pneumophila airway infection.

  18. Molecular typing of Legionella pneumophila from air-conditioning cooling waters using mip gene, SBT, and FAFLP methods.

    Science.gov (United States)

    Gong, Xiangli; Li, Juntao; Zhang, Ying; Hou, Shuiping; Qu, Pinghua; Yang, Zhicong; Chen, Shouyi

    2017-08-01

    Legionella spp. are important waterborne pathogens. Molecular typing has become an important method for outbreaks investigations and source tracking of Legionnaires. In a survey program conducted by the Guangzhou Center for Disease Control and Prevention, multiple serotypes Legionella pneumophila (L. pneumophila) were isolated from waters in air-conditioning cooling towers in urban Guangzhou region, China between 2008 and 2011. Three genotyping methods, mip (macrophage infectivity potentiator) genotyping, SBT (sequence-based typing), and FAFLP (fluorescent amplified fragment length polymorphism analysis) were used to type these waterborne L. pneumophila isolates. The three methods were capable of typing all the 134 isolates and a reference strain of L. pneumophila (ATCC33153), with discriminatory indices of 0.7034, 0.9218, and 0.9376, for the mip, SBT, and FAFLP methods respectively. Among the 9 serotypes of the 134 isolates, 10, 50, and 34 molecular types were detected by the mip, SBT, and FAFLP methods respectively. The mip genotyping and SBT typing are more feasible for inter-laboratory results sharing and comparison of different types of L. pneumophila. The SBT and FAFLP typing methods were rapid with higher discriminatory abilities. Combinations of two or more of the typing methods enables more accurate typing of Legionella isolates for outbreak investigations and source tracking of Legionnaires. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Profits and Exploitation: A Reappraisal

    OpenAIRE

    Yoshihara, Naoki; Veneziani, Roberto

    2011-01-01

    This paper provides a mathematical analysis of the Marxian theory of the exploitation of labour in general equilibrium models. The two main definitions of Marxian exploitation in the literature, proposed by Morishima (1974) and Roemer (1982), respectively, are analysed in the context of general convex economies. It is shown that, contrary to the received view, in general these definitions do not preserve the so-called Fundamental Marxian Theorem (FMT), which states that the exploitation of la...

  20. Distribution of Legionella pneumophila bacteria and Naegleria and Hartmannella amoebae in thermal saline baths used in balneotherapy.

    Science.gov (United States)

    Zbikowska, Elżbieta; Walczak, Maciej; Krawiec, Arkadiusz

    2013-01-01

    The present study was aimed at investigating the coexistence and interactions between free living amoebae of Naegleria and Hartmannella genera and pathogenic Legionella pneumophila bacteria in thermal saline baths used in balneotherapy in central Poland. Water samples were collected from November 2010 to May 2011 at intervals longer than 1 month. The microorganisms were detected with the use of a very sensitive fluorescence in situ hybridisation method. In addition, the morphology of the amoebae was studied. Despite relatively high salinity level, ranging from 1.5 to 5.0 %, L. pneumophila were found in all investigated baths, although their number never exceeded 10(6) cells dm(-3). Hartmannella were not detected, while Naegleria fowleri were found in one bath. The observation that N. fowleri and L. pneumophila may coexist in thermal saline baths is the first observation emphasising potential threat from these microorganisms in balneotherapy.

  1. Consensual exploitation : the moral wrong in exploitation and legal restrictions on consensual exploitative transactions

    OpenAIRE

    van der Neut, Wendy

    2014-01-01

    This thesis is about so-­‐called consensual exploitative transactions: transactions to which all parties agree voluntarily, and which are beneficial for all parties, but which are still widely considered exploitative, and for that reason legally restricted in many countries. The thesis asks two main questions: 1. What is wrong with consensual exploitation? 2.What implications does the answer to this question have for the legal restriction of consensual transactions ...

  2. The Sensitization of Legionella pneumophila to Some Antibiotics by Reserpine and Anti-Legionella Effects of Different Benzofuranone Derivatives

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    Mohsen Khaleghi

    2015-10-01

    Full Text Available Background: Legionella pneumophila is  a  dangerous pathogenic bacterium can cause serious infectious diseases especially in hospitalized immuno-compromised patients. This bacterium is shown to be resistant against different antibiotics. Resistance against a wide range of antibiotics is usually mediated by efflux pump in bacteria. Efflux pumps are proteinaceous transporters localized in the cytoplasmic membrane of all kinds of cells which excreted antibiotics outside the cells. However, synthesis of new anti-Legionella compounds or selection of resistant modulating agents are useful strategy to combat with L. pneumophilain the future.Methods: In this study the antibacterial activity of some benzofuranone derivatives have been investigated by disk diffusion method against L. pneumophila. Also the sensitivity of this test strain was evaluated against 19 antibiotics and the combination effect of reserpine at a sub-inhibitory concentration was further studied with these antibiotics using disk diffusion method with some modifications.Conclusion: Among the different synthetic compounds which were tested against L. pneumophila, the most antibacterial activity was observed for compounds 1j and 1m which contain hydroxyl and methoxy groups on the C-6 and C-7 positionsagainst L. pneumophila. To evaluate whether efflux pumps are active in L. pneumophila or not an efflux inhibitor (reserpine was tested in combination of different antibiotics against this test strain. Reserpine significantly enhanced the antibacterial activities of kanamycin, nitrofurantoin, co-trimoxazole, erythromycin, ofloxacillin, gentamycin, rifampin, ciprofloxacin, nalidixic acid, minocycline, tobramycin, and amikacin against L. pneumophila which shows the resistances to these antibiotics are mediated by efflux system in this bacterium.

  3. Distinct difference of flaA genotypes of Legionella pneumophila between isolates from bath water and cooling tower water.

    Science.gov (United States)

    Amemura-Maekawa, Junko; Kura, Fumiaki; Chang, Bin; Suzuki-Hashimoto, Atsuko; Ichinose, Masayuki; Endo, Takuro; Watanabe, Haruo

    2008-09-01

    To investigate the genetic difference of Legionella pneumophila in human-made environments, we collected isolates of L. pneumophila from bath water (n = 167) and cooling tower water (n = 128) primarily in the Kanto region in 2001 and 2005. The environmental isolates were serogrouped and sequenced for a target region of flaA. A total of 14 types of flaA genotypes were found: 10 from cooling tower water and nine from bath water. The flaA genotypes of isolates from cooling tower water were quite different from those of bath water.

  4. Inhibition of host cell translation elongation by Legionella pneumophila blocks the host cell unfolded protein response.

    Science.gov (United States)

    Hempstead, Andrew D; Isberg, Ralph R

    2015-12-08

    Cells of the innate immune system recognize bacterial pathogens by detecting common microbial patterns as well as pathogen-specific activities. One system that responds to these stimuli is the IRE1 branch of the unfolded protein response (UPR), a sensor of endoplasmic reticulum (ER) stress. Activation of IRE1, in the context of Toll-like receptor (TLR) signaling, induces strong proinflammatory cytokine induction. We show here that Legionella pneumophila, an intravacuolar pathogen that replicates in an ER-associated compartment, blocks activation of the IRE1 pathway despite presenting pathogen products that stimulate this response. L. pneumophila TLR ligands induced the splicing of mRNA encoding XBP1s, the main target of IRE1 activity. L. pneumophila was able to inhibit both chemical and bacterial induction of XBP1 splicing via bacterial translocated proteins that interfere with host protein translation. A strain lacking five translocated translation elongation inhibitors was unable to block XBP1 splicing, but this could be rescued by expression of a single such inhibitor, consistent with limitation of the response by translation elongation inhibitors. Chemical inhibition of translation elongation blocked pattern recognition receptor-mediated XBP1 splicing, mimicking the effects of the bacterial translation inhibitors. In contrast, host cell-promoted inhibition of translation initiation in response to the pathogen was ineffective in blocking XBP1 splicing, demonstrating the need for the elongation inhibitors for protection from the UPR. The inhibition of host translation elongation may be a common strategy used by pathogens to limit the innate immune response by interfering with signaling via the UPR.

  5. Diverse mechanisms of metaeffector activity in an intracellular bacterial pathogen, Legionella pneumophila.

    Science.gov (United States)

    Urbanus, Malene L; Quaile, Andrew T; Stogios, Peter J; Morar, Mariya; Rao, Chitong; Di Leo, Rosa; Evdokimova, Elena; Lam, Mandy; Oatway, Christina; Cuff, Marianne E; Osipiuk, Jerzy; Michalska, Karolina; Nocek, Boguslaw P; Taipale, Mikko; Savchenko, Alexei; Ensminger, Alexander W

    2016-12-16

    Pathogens deliver complex arsenals of translocated effector proteins to host cells during infection, but the extent to which these proteins are regulated once inside the eukaryotic cell remains poorly defined. Among all bacterial pathogens, Legionella pneumophila maintains the largest known set of translocated substrates, delivering over 300 proteins to the host cell via its Type IVB, Icm/Dot translocation system. Backed by a few notable examples of effector-effector regulation in L. pneumophila, we sought to define the extent of this phenomenon through a systematic analysis of effector-effector functional interaction. We used Saccharomyces cerevisiae, an established proxy for the eukaryotic host, to query > 108,000 pairwise genetic interactions between two compatible expression libraries of ~330 L. pneumophila-translocated substrates. While capturing all known examples of effector-effector suppression, we identify fourteen novel translocated substrates that suppress the activity of other bacterial effectors and one pair with synergistic activities. In at least nine instances, this regulation is direct-a hallmark of an emerging class of proteins called metaeffectors, or "effectors of effectors". Through detailed structural and functional analysis, we show that metaeffector activity derives from a diverse range of mechanisms, shapes evolution, and can be used to reveal important aspects of each cognate effector's function. Metaeffectors, along with other, indirect, forms of effector-effector modulation, may be a common feature of many intracellular pathogens-with unrealized potential to inform our understanding of how pathogens regulate their interactions with the host cell. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

  6. Application of ozonation process for the removal of Legionella pneumophila from water

    Directory of Open Access Journals (Sweden)

    Mohammad Safaee

    2015-09-01

    Full Text Available Background: Legionella pneumophila mortality and morbidity is a health concern worldwide. Due to the role of water in transmission of Legionenlla, several techniques have been used for water disinfection. This research was aimed to analyze the efficacy of ozonation process and the effects of bacterial density, contact time and pH on the removal of Legionella pneumophila from water. Methods: Legionella pneumophila was isolated from hospital water line and spiked into sterile drinking water with 300, 700 and 1000 CFU/ml densities. Ozonation was conducted within 1 L batch glass reactor with injection of 5 mg/h and contact time of 5 to 30 minutes at pH = 5, 7 and 9. Legionella culture was performed in supplemented BCYE containing GVPC and thermal treatment. After ozonation, the developed colonies were identified via biochemical and morphological tests. Results: In pH =5, the contact time 25 min and pH= 7 as well as the contact time 30 min, increase of legionella density from 300 to 1000 CFU/ml led to the reduction of removal efficiency from 100 to 87% and 100 to 82%, respectively. In pH=9 and contact time 20 min with the same bacterial density, 300 to 1000 CFU/ml, the disinfection efficacy was decreased from 100 to 91.5 %. Conclusion: Ozonation is an appropriate technique for elimination of legionella from water. The increased bacterial density led to the reduction of removal efficiency. The lowest and highest performance rates were obtained in pH=7 and 9, respectively.

  7. Phylogenetic reconstruction of the Legionella pneumophila Philadelphia-1 laboratory strains through comparative genomics.

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    Chitong Rao

    Full Text Available Over 20 years ago, two groups independently domesticated Legionella pneumophila from a clinical isolate of bacteria collected during the first recognized outbreak of Legionnaires' disease (at the 1976 American Legion's convention in Philadelphia. These two laboratory strains, JR32 and Lp01, along with their derivatives, have been disseminated to a number of laboratories around the world and form the cornerstone of much of the research conducted on this important pathogen to date. Nevertheless, no exhaustive examination of the genetic distance between these strains and their clinical progenitor has been performed thus far. Such information is of paramount importance for making sense of several phenotypic differences observed between these strains. As environmental replication of L. pneumophila is thought to exclusively occur within natural protozoan hosts, retrospective analysis of the domestication and axenic culture of the Philadelphia-1 progenitor strain by two independent groups also provides an excellent opportunity to uncover evidence of adaptation to the laboratory environment. To reconstruct the phylogenetic relationships between the common laboratory strains of L. pneumophila Philadelphia-1 and their clinical ancestor, we performed whole-genome Illumina resequencing of the two founders of each laboratory lineage: JR32 and Lp01. As expected from earlier, targeted studies, Lp01 and JR32 contain large deletions in the lvh and tra regions, respectively. By sequencing additional strains derived from Lp01 (Lp02 and Lp03, we retraced the phylogeny of these strains relative to their reported ancestor, thereby reconstructing the evolutionary dynamics of each laboratory lineage from genomic data.

  8. Geostatistics – a tool applied to the distribution of Legionella pneumophila in a hospital water system

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    Pasqualina Laganà

    2015-12-01

    Full Text Available [b]Introduction.[/b] Legionnaires’ disease is normally acquired by inhalation of legionellae from a contaminated environmental source. Water systems of large buildings, such as hospitals, are often contaminated with legionellae and therefore represent a potential risk for the hospital population. The aim of this study was to evaluate the potential contamination of [i]Legionella pneumophila[/i] (LP in a large hospital in Italy through georeferential statistical analysis to assess the possible sources of dispersion and, consequently, the risk of exposure for both health care staff and patients. [b]Materials and Method. [/b]LP serogroups 1 and 2–14 distribution was considered in the wards housed on two consecutive floors of the hospital building. On the basis of information provided by 53 bacteriological analysis, a ‘random’ grid of points was chosen and spatial geostatistics or [i]FAIk Kriging[/i] was applied and compared with the results of classical statistical analysis. [b]Results[/b]. Over 50% of the examined samples were positive for [i]Legionella pneumophila[/i]. LP 1 was isolated in 69% of samples from the ground floor and in 60% of sample from the first floor; LP 2–14 in 36% of sample from the ground floor and 24% from the first. The iso-estimation maps show clearly the most contaminated pipe and the difference in the diffusion of the different [i]L. pneumophila[/i] serogroups. [b]Conclusion.[/b] Experimental work has demonstrated that geostatistical methods applied to the microbiological analysis of water matrices allows a better modeling of the phenomenon under study, a greater potential for risk management and a greater choice of methods of prevention and environmental recovery to be put in place with respect to the classical statistical analysis.

  9. MTOR-Driven Metabolic Reprogramming Regulates Legionella pneumophila Intracellular Niche Homeostasis

    Science.gov (United States)

    Abshire, Camille F.; Roy, Craig R.

    2016-01-01

    Vacuolar bacterial pathogens are sheltered within unique membrane-bound organelles that expand over time to support bacterial replication. These compartments sequester bacterial molecules away from host cytosolic immunosurveillance pathways that induce antimicrobial responses. The mechanisms by which the human pulmonary pathogen Legionella pneumophila maintains niche homeostasis are poorly understood. We uncovered that the Legionella-containing vacuole (LCV) required a sustained supply of host lipids during expansion. Lipids shortage resulted in LCV rupture and initiation of a host cell death response, whereas excess of host lipids increased LCVs size and housing capacity. We found that lipids uptake from serum and de novo lipogenesis are distinct redundant supply mechanisms for membrane biogenesis in Legionella-infected macrophages. During infection, the metabolic checkpoint kinase Mechanistic Target of Rapamycin (MTOR) controlled lipogenesis through the Serum Response Element Binding Protein 1 and 2 (SREBP1/2) transcription factors. In Legionella-infected macrophages a host-driven response that required the Toll-like receptors (TLRs) adaptor protein Myeloid differentiation primary response gene 88 (Myd88) dampened MTOR signaling which in turn destabilized LCVs under serum starvation. Inactivation of the host MTOR-suppression pathway revealed that L. pneumophila sustained MTOR signaling throughout its intracellular infection cycle by a process that required the upstream regulator Phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) and one or more Dot/Icm effector proteins. Legionella-sustained MTOR signaling facilitated LCV expansion and inhibition of the PI3K-MTOR-SREPB1/2 axis through pharmacological or genetic interference or by activation of the host MTOR-suppression response destabilized expanding LCVs, which in turn triggered cell death of infected macrophages. Our work identified a host metabolic requirement for LCV homeostasis and demonstrated that L

  10. Characterization of a major 31-kilodalton peptidoglycan-bound protein of Legionella pneumophila

    International Nuclear Information System (INIS)

    Butler, C.A.; Hoffman, P.S.

    1990-01-01

    A 31-kilodalton (kDa) protein was solubilized from the peptidoglycan (PG) fraction of Legionella pneumophila after treatment with either N-acetylmuramidase from the fungus Chalaropsis sp. or with mutanolysin from Streptomyces globisporus. The protein exhibited a ladderlike banding pattern by autoradiography when radiolabeled [(35S]cysteine or [35S]methionine) PG material was extensively treated with hen lysozyme. The banding patterns ranging between 31 and 45 kDa and between 55 and 60 kDa resolved as a single 31-kDa protein when the material was subsequently treated with N-acetylmuramidase. Analysis of the purified 31-kDa protein for diaminopimelic acid by gas chromatography revealed 1 mol of diaminopimelic acid per mol of protein. When outer membrane PG material containing the major outer membrane porin protein was treated with N-acetylmuramidase or mutanolysin, both the 28.5-kDa major outer membrane protein and the 31-kDa protein were solubilized from the PG material under reducing conditions. In the absence of 2-mercaptoethanol, a high-molecular-mass complex (100 kDa) was resolved. The results of this study indicate that a 31-kDa PG-bound protein is a major component of the cell wall of L. pneumophila whose function may be to anchor the major outer membrane protein to PG. Finally, a survey of other Legionella species and other serogroups of L. pneumophila suggested that PG-bound proteins may be a common feature of this genus

  11. Genomic characterization of a large outbreak of Legionella pneumophila serogroup 1 strains in Quebec City, 2012.

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    Simon Lévesque

    Full Text Available During the summer of 2012, a major Legionella pneumophila serogroup 1 outbreak occurred in Quebec City, Canada, which caused 182 declared cases of Legionnaire's disease and included 13 fatalities. Legionella pneumophila serogroup 1 isolates from 23 patients as well as from 32 cooling towers located in the vicinity of the outbreak were recovered for analysis. In addition, 6 isolates from the 1996 Quebec City outbreak and 4 isolates from patients unrelated to both outbreaks were added to allow comparison. We characterized the isolates using pulsed-field gel electrophoresis, sequence-based typing, and whole genome sequencing. The comparison of patients-isolated strains to cooling tower isolates allowed the identification of the tower that was the source of the outbreak. Legionella pneumophila strain Quebec 2012 was identified as a ST-62 by sequence-based typing methodology. Two new Legionellaceae plasmids were found only in the epidemic strain. The LVH type IV secretion system was found in the 2012 outbreak isolates but not in the ones from the 1996 outbreak and only in half of the contemporary human isolates. The epidemic strains replicated more efficiently and were more cytotoxic to human macrophages than the environmental strains tested. At least four Icm/Dot effectors in the epidemic strains were absent in the environmental strains suggesting that some effectors could impact the intracellular replication in human macrophages. Sequence-based typing and pulsed-field gel electrophoresis combined with whole genome sequencing allowed the identification and the analysis of the causative strain including its likely environmental source.

  12. Activity of Six Essential Oils Extracted from Tunisian Plants against Legionella pneumophila.

    Science.gov (United States)

    Chaftar, Naouel; Girardot, Marion; Quellard, Nathalie; Labanowski, Jérôme; Ghrairi, Tawfik; Hani, Khaled; Frère, Jacques; Imbert, Christine

    2015-10-01

    The aim of this study was to investigate the composition of six essential oils extracted from Tunisian plants, i.e., Artemisia herba-alba Asso, Citrus sinensis (L.) Osbeck, Juniperus phoenicea L., Rosmarinus officinalis L., Ruta graveolens L., and Thymus vulgaris L., and to evaluate their activity against Legionella pneumophila (microdilution assays). Eight Legionella pneumophila strains were studied, including the two well-known serogroup 1 Lens and Paris strains as controls and six environmental strains isolated from Tunisian spas belonging to serogroups 1, 4, 5, 6, and 8. The essential oils were generally active against L. pneumophila. The activities of the A. herba-alba, C. sinensis, and R. officinalis essential oils were strain-dependent, whereas those of the J. phoenicea and T. vulgaris oils, showing the highest anti-Legionella activities, with minimum inhibitory concentrations (MICs) lower than 0.03 and lower than or equal to 0.07 mg/ml, respectively, were independent of the strains' serogroup. Moreover, the microorganisms treated with T. vulgaris essential oil were shorter, swollen, and less electron-dense compared to the untreated controls. Isoborneol (20.91%), (1S)-α-pinene (18.30%) β-phellandrene (8.08%), α-campholenal (7.91%), and α-phellandrene (7.58%) were the major components isolated from the J. phoenicea oil, while carvacrol (88.50%) was the main compound of the T. vulgaris oil, followed by p-cymene (7.86%). This study highlighted the potential interest of some essential oils extracted from Tunisian plants as biocides to prevent the Legionella risk. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  13. Reassessing the role of DotF in the Legionella pneumophila type IV secretion system.

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    Molly C Sutherland

    Full Text Available Legionella pneumophila, the causative agent of a severe pneumonia termed Legionnaires' Disease, survives and replicates within both protozoan hosts and human alveolar macrophages. Intracellular survival is dependent upon secretion of a plethora of protein effectors that function to form a replicative vacuole, evade the endocytic pathway and subvert host immune defenses. Export of these factors requires a type IV secretion system (T4SS called Dot/Icm that is composed of twenty-seven proteins. This report focuses on the DotF protein, which was previously postulated to have several different functions, one of which centered on binding Dot/Icm substrates. In this report, we examined if DotF functions as the T4SS inner membrane receptor for Dot/Icm substrates. Although we were able to recapitulate the previously published bacterial two-hybrid interaction between DotF and several substrates, the interaction was not dependent on the Dot/Icm substrates' signal sequences as predicted for a substrate:receptor interaction. In addition, binding did not require the cytoplasmic domain of DotF, which was anticipated to be involved in recognizing substrates in the cytoplasm. Finally, inactivation of dotF did not abolish intracellular growth of L. pneumophila or translocation of substrates, two phenotypes dependent on the T4SS receptor. These data strongly suggest that DotF does not act as the major receptor for Dot/Icm substrates and therefore likely performs an accessory function within the core-transmembrane subcomplex of the L. pneumophila Dot/Icm type IV secretion system.

  14. Genetic Characterization of Legionella pneumophila Isolated from a Common Watershed in Comunidad Valenciana, Spain.

    Science.gov (United States)

    Sánchez-Busó, Leonor; Coscollá, Mireia; Pinto-Carbó, Marta; Catalán, Vicente; González-Candelas, Fernando

    2013-01-01

    Legionella pneumophila infects humans to produce legionellosis and Pontiac fever only from environmental sources. In order to establish control measures and study the sources of outbreaks it is essential to know extent and distribution of strain variants of this bacterium in the environment. Sporadic and outbreak-related cases of legionellosis have been historically frequent in the Comunidad Valenciana region (CV, Spain), with a high prevalence in its Southeastern-most part (BV). Environmental investigations for the detection of Legionella pneumophila are performed in this area routinely. We present a population genetics study of 87 L. pneumophila strains isolated in 13 different localities of the BV area irrigated from the same watershed and compare them to a dataset of 46 strains isolated in different points of the whole CV. Our goal was to compare environmental genetic variation at two different geographic scales, at county and regional levels. Genetic diversity, recombination and population structure were analyzed with Sequence-Based Typing data and three intergenic regions. The results obtained reveal a low, but detectable, level of genetic differentiation between both datasets, mainly, but not only, attributed to the occurrence of unusual variants of the neuA locus present in the BV populations. This differentiation is still detectable when the 10 loci considered are analyzed independently, despite the relatively high incidence of the most common genetic variant in this species, sequence type 1 (ST-1). However, when the genetic data are considered without their associated geographic information, four major groups could be inferred at the genetic level which did not show any correlation with sampling locations. The overall results indicate that the population structure of these environmental samples results from the joint action of a global, widespread ST-1 along with genetic differentiation at shorter geographic distances, which in this case are related to

  15. Crystallization and preliminary crystallographic analysis of an aminoglycoside kinase from Legionella pneumophila

    International Nuclear Information System (INIS)

    Lemke, Christopher T.; Hwang, Jiyoung; Xiong, Bing; Cianciotto, Nicholas P.; Berghuis, Albert M.

    2005-01-01

    Two crystal forms of the antibiotic resistance enzyme APH(9)-Ia from L. pneumophila are reported. 9-Aminoglycoside phosphotransferase type Ia [APH(9)-Ia] is a resistance factor in Legionella pneuemophila, the causative agent of legionnaires’ disease. It is responsible for providing intrinsic resistance to the antibiotic spectinomycin. APH(9)-Ia phosphorylates one of the hydroxyl moieties of spectinomycin in an ATP-dependent manner, abolishing the antibiotic properties of this drug. Here, the crystallization and preliminary X-ray studies of this enzyme in two crystal forms is reported. One of the these crystal forms provides diffraction data to a resolution of 1.7 Å

  16. Impact of drinking water conditions and copper materials on downstream biofilm microbial communities and legionella pneumophila colonization

    Science.gov (United States)

    Legionella pneumophila, the medically important species within the genus Legionella, is a concern in engineered water systems. Its ability to amplify within free-living amoebae is well documented, but its interactions/ecology within the microbial community of drinking water biofi...

  17. Aminoacyl-tRNA-charged eukaryotic elongation factor 1A is a bona fide substrate for Legionelle pneumophila effector glucosyltransferases

    DEFF Research Database (Denmark)

    Tzivelekidis, Tina; Jank, Thomas; Pohl, Corinna

    2011-01-01

    Legionella pneumophila, which is the causative organism of Legionnaires disease, translocates numerous effector proteins into the host cell cytosol by a type IV secretion system during infection. Among the most potent effector proteins of Legionella are glucosyltransferases (Lgt’s), which...

  18. Differential growth of Legionella pneumophila strains within a range of amoebae at various temperatures associated with in-premise plumbing

    Science.gov (United States)

    The potential effect of in-premise plumbing temperatures (24, 32, 37 and 41 °C) on the growth of five different L. pneumophila strains within free-living amoebae (Acanthamoeba polyphaga, Hartmannella vermiformis and Naegleria fowleri) was examined. Compared to controls only fed E...

  19. Free-living protozoa in drinking water supplies: community composition and role as hosts for Legionella pneumophila

    NARCIS (Netherlands)

    Valster, R.M.

    2011-01-01

    Free-living protozoa in drinking water supplies: community composition and role as hosts for Legionella pneumophila


    Free-living protozoa, which feed on bacteria, play an important role in the communities of microorganisms and invertebrates in drinking water supplies and in (warm)

  20. Prevalence of Legionella pneumophila in water distribution systems in hospitals and public buildings of the Lublin region of eastern Poland

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    Agnieszka Sikora

    2015-05-01

    The water samples collected form the hot water supply system of hospitals and public buildings showed exceeded counts of L. pneumophila, indicating the risk of infection. The constant monitoring of water distribution systems is an important element of the control of infections caused by these organisms.

  1. Comprehensive identification of protein substrates of the Dot/Icm type IV transporter of Legionella pneumophila.

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    Wenhan Zhu

    2011-03-01

    Full Text Available A large number of proteins transferred by the Legionella pneumophila Dot/Icm system have been identified by various strategies. With no exceptions, these strategies are based on one or more characteristics associated with the tested proteins. Given the high level of diversity exhibited by the identified proteins, it is possible that some substrates have been missed in these screenings. In this study, we took a systematic method to survey the L. pneumophila genome by testing hypothetical orfs larger than 300 base pairs for Dot/Icm-dependent translocation. 798 of the 832 analyzed orfs were successfully fused to the carboxyl end of β-lactamase. The transfer of the fusions into mammalian cells was determined using the β-lactamase reporter substrate CCF4-AM. These efforts led to the identification of 164 proteins positive in translocation. Among these, 70 proteins are novel substrates of the Dot/Icm system. These results brought the total number of experimentally confirmed Dot/Icm substrates to 275. Sequence analysis of the C-termini of these identified proteins revealed that Lpg2844, which contains few features known to be important for Dot/Icm-dependent protein transfer can be translocated at a high efficiency. Thus, our efforts have identified a large number of novel substrates of the Dot/Icm system and have revealed the diverse features recognizable by this protein transporter.

  2. New crystal forms of NTPDase1 from the bacterium Legionella pneumophila

    International Nuclear Information System (INIS)

    Zebisch, Matthias; Schäfer, Petra; Lauble, Peter; Sträter, Norbert

    2013-01-01

    The soluble NTPDase1 from L. pneumophila was crystallized in six crystal forms and the structure was solved using a sulfur SAD approach. Nucleoside triphosphate diphosphohydrolases (NTPDases) are a large class of nucleotidases that hydrolyze the (γ/β)- and (β/α)-anhydride bonds of nucleoside triphosphates and diphosphates, respectively. NTPDases are found throughout the eukaryotic domain. In addition, a very small number of members can be found in bacteria, most of which live as parasites of eukaryotic hosts. NTPDases of intracellular and extracellular parasites are emerging as important regulators for the survival of the parasite. To deepen the knowledge of the structure and function of this enzyme class, recombinant production of the NTPDase1 from the bacterium Legionella pneumophila has been established. The protein could be crystallized in six crystal forms, of which one has been described previously. The crystals diffracted to resolutions of between 1.4 and 2.5 Å. Experimental phases determined by a sulfur SAD experiment using an orthorhombic crystal form produced an interpretable electron-density map

  3. Hyperoxia accelerates Fas-mediated signaling and apoptosis in the lungs of Legionella pneumophila pneumonia

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    Tanabe Yoshinari

    2011-04-01

    Full Text Available Abstract Background Oxygen supplementation is commonly given to the patients with severe pneumonia including Legionella disease. Recent data suggested that apoptosis may play an important role, not only in the pathogenesis of Legionella pneumonia, but also in oxygen-induced tissue damage. In the present study, the lethal sensitivity to Legionella pneumonia were compared in the setting of hyperoxia between wild-type and Fas-deficient mice. Findings C57BL/6 mice and B6.MRL-Faslpr mice characterized with Fas-deficiency were used in this study. After intratracheal administration of L. pneumophila, mice were kept in hyperoxic conditions (85-90% O2 conc. in an airtight chamber for 3 days. Bone-marrow derived macrophages infected with L. pneumophila were also kept in hyperoxic conditions. Caspase activity and cytokine production were determined by using commercially available kits. Smaller increases of several apoptosis markers, such as caspase-3 and -8, were demonstrated in Fas-deficient mice, even though the bacterial burdens in Fas-deficient and wild type mice were similar. Bone-marrow derived macrophages from Fas-deficient mice were shown to be more resistant to Legionella-induced cytotoxicity than those from wild-type mice under hyperoxia. Conclusions These results demonstrated that Fas-mediated signaling and apoptosis may be a crucial factor in the pathogenesis of Legionella pneumonia in the setting of hyperoxia.

  4. Essential roles and regulation of the Legionella pneumophila collagen-like adhesin during biofilm formation.

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    Julia Mallegol

    Full Text Available Legionellosis is mostly caused by Legionella pneumophila (Lp and is defined by a severe respiratory illness with a case fatality rate ranging from 5 to 80%. In a previous study, we showed that a glycosaminoglycan (GAG-binding adhesin of Lp, named Lcl, is produced during legionellosis and is unique to the L. pneumophila species. Importantly, a mutant depleted in Lcl (Δlpg2644 is impaired in adhesion to GAGs and epithelial cells and in biofilm formation. Here, we examine the molecular function(s of Lcl and the transcriptional regulation of its encoding gene during different stages of the biofilm development. We show that the collagen repeats and the C-terminal domains of Lcl are crucial for the production of biofilm. We present evidence that Lcl is involved in the early step of surface attachment but also in intercellular interactions. Furthermore, we address the relationship between Lcl gene regulation during biofilm formation and quorum sensing (QS. In a static biofilm assay, we show that Lcl is differentially regulated during growth phases and biofilm formation. Moreover, we show that the transcriptional regulation of lpg2644, mediated by a prototype of QS signaling homoserine lactone (3OC12-HSL, may play a role during the biofilm development. Thus, transcriptional down-regulation of lpg2644 may facilitate the dispersion of Lp to reinitiate biofilm colonization on a distal surface.

  5. Effects of culture conditions and biofilm formation on the iodine susceptibility of Legionella pneumophila

    Science.gov (United States)

    Cargill, K. L.; Pyle, B. H.; Sauer, R. L.; McFeters, G. A.

    1992-01-01

    The susceptibility of Legionella pneumophila to iodination was studied with cultures grown in well water, on rich agar media, and attached to stainless-steel surfaces. Legionella pneumophila grown in water cultures in association with other microorganisms were less sensitive to disinfection by chlorine and iodine than were agar-passaged cultures. Differences in sensitivity to disinfection between water-cultured and agar-grown legionellae were determined by comparing C x T values (concentration in milligrams per litre multiplied by time in minutes to achieve 99% decrease in viability) and CM x T values (concentration in molarity). Iodine (1500x) gave a greater difference in CM x T values than did chlorine (68x). Iodine was 50 times more effective than chlorine when used with agar-grown cultures but was only twice as effective when tested against water-grown Legionella cultures. C x T x S values (C x T multiplied by percent survivors), which take into consideration the percent surviving bacteria, were used to compare sensitivities in very resistant populations, such as those in biofilms. Water cultures of legionellae associated with stainless-steel surfaces were 135 times more resistant to iodination than were unattached legionellae, and they were 210,000 times more resistant than were agar-grown cultures. These results indicate that the conditions under which legionellae are grown can dramatically affect their susceptibility to some disinfectants and must be considered when evaluating the efficacy of a disinfecting agent.

  6. Removal of bacteria Legionella pneumophila, Escherichia coli, and Bacillus subtilis by (super)cavitation.

    Science.gov (United States)

    Šarc, Andrej; Kosel, Janez; Stopar, David; Oder, Martina; Dular, Matevž

    2018-04-01

    In sufficient concentrations, the pathogenic bacteria L. pneumophila can cause a respiratory illness that is known as the "Legionnaires" disease. Moreover, toxic Shiga strains of bacteria E. coli can cause life-threatening hemolytic-uremic syndrome. Because of the recent restrictions imposed on the usage of chlorine, outbreaks of these two bacterial species have become more common. In this study we have developed a novel rotation generator and its effectiveness against bacteria Legionella pneumophila and Escherichia coli was tested for various types of hydrodynamic cavitation (attached steady cavitation, developed unsteady cavitation and supercavitation). The results show that the supercavitation was the only effective form of cavitation. It enabled more than 3 logs reductions for both bacterial species and was also effective against a more persistent Gram positive bacteria, B. subtilis. The deactivation mechanism is at present unknown. It is proposed that when bacterial cells enter a supercavitation cavity, an immediate pressure drop occurs and this results in bursting of the cellular membrane. The new rotation generator that induced supercavitation proved to be economically and microbiologically far more effective than the classical Venturi section (super)cavitation. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Hot water systems as sources of Legionella pneumophila in hospital and nonhospital plumbing fixtures.

    Science.gov (United States)

    Wadowsky, R M; Yee, R B; Mezmar, L; Wing, E J; Dowling, J N

    1982-05-01

    Samples obtained from plumbing systems of hospitals, nonhospital institutions and homes were cultured for Legionella spp. by plating the samples directly on a selective medium. Swab samples were taken from the inner surfaces of faucet assemblies (aerators, spouts, and valve seats), showerheads, and shower pipes. Water and sediment were collected from the bottom of hot-water tanks. Legionella pneumophila serogroups 1, 5, and 6 were recovered from plumbing fixtures of the hospitals and nonhospital institutions and one of five homes. The legionellae (7 to 13,850 colony-forming units per ml) were also present in water and sediment from hot-water tanks maintained at 30 to 54 degrees C, but not in those maintained at 71 and 77 degrees C. Legionella micdadei was isolated from one tank. Thus legionellae are present in hot-water tanks which are maintained at warm temperatures or whose design results in warm temperatures at the bottom of the tanks. We hypothesize that hot-water tanks are a breeding site and a major source of L. pneumophila for the contamination of plumbing systems. The existence of these bacteria in the plumbing systems and tanks was not necessarily associated with disease. The extent of the hazard of this contamination needs to be delineated.

  8. Biofilm Composition and Threshold Concentration for Growth of Legionella pneumophila on Surfaces Exposed to Flowing Warm Tap Water without Disinfectant.

    Science.gov (United States)

    van der Kooij, Dick; Bakker, Geo L; Italiaander, Ronald; Veenendaal, Harm R; Wullings, Bart A

    2017-03-01

    Legionella pneumophila in potable water installations poses a potential health risk, but quantitative information about its replication in biofilms in relation to water quality is scarce. Therefore, biofilm formation on the surfaces of glass and chlorinated polyvinyl chloride (CPVC) in contact with tap water at 34 to 39°C was investigated under controlled hydraulic conditions in a model system inoculated with biofilm-grown L. pneumophila The biofilm on glass (average steady-state concentration, 23 ± 9 pg ATP cm -2 ) exposed to treated aerobic groundwater (0.3 mg C liter -1 ; 1 μg assimilable organic carbon [AOC] liter -1 ) did not support growth of the organism, which also disappeared from the biofilm on CPVC (49 ± 9 pg ATP cm -2 ) after initial growth. L. pneumophila attained a level of 4.3 log CFU cm -2 in the biofilms on glass (1,055 ± 225 pg ATP cm -2 ) and CPVC (2,755 ± 460 pg ATP cm -2 ) exposed to treated anaerobic groundwater (7.9 mg C liter -1 ; 10 μg AOC liter -1 ). An elevated biofilm concentration and growth of L. pneumophila were also observed with tap water from the laboratory. The Betaproteobacteria Piscinibacter and Methyloversatilis and amoeba-resisting Alphaproteobacteria predominated in the clones and isolates retrieved from the biofilms. In the biofilms, the Legionella colony count correlated significantly with the total cell count (TCC), heterotrophic plate count, ATP concentration, and presence of Vermamoeba vermiformis This amoeba was rarely detected at biofilm concentrations of water-associated disease outbreaks reported in the United States. The organism proliferates in biofilms on surfaces exposed to warm water in engineered freshwater installations. An investigation with a test system supplied with different types of warm drinking water without disinfectant under controlled hydraulic conditions showed that treated aerobic groundwater (0.3 mg liter -1 of organic carbon) induced a low biofilm concentration that supported no or very

  9. AUTOMATED DEAD-END ULTRAFILTRATION FOR ENHANCED SURVEILLANCE OF LEGIONELLA 2 PNEUMOPHILA AND LEGIONELLA SPP. IN COOLING TOWER WATERS

    Energy Technology Data Exchange (ETDEWEB)

    Brigmon, R.; Leskinen, S.; Kearns, E.; Jones, W.; Miller, R.; Betivas, C.; Kingsley, M.; Lim, D.

    2011-10-10

    Detection of Legionella pneumophila in cooling towers and domestic hot water systems involves concentration by centrifugation or membrane filtration prior to inoculation onto growth media or analysis using techniques such as PCR or immunoassays. The Portable Multi-use Automated Concentration System (PMACS) was designed for concentrating microorganisms from large volumes of water in the field and was assessed for enhancing surveillance of L. pneumophila at the Savannah River Site, SC. PMACS samples (100 L; n = 28) were collected from six towers between August 2010 and April 2011 with grab samples (500 ml; n = 56) being collected before and after each PMACS sample. All samples were analyzed for the presence of L. pneumophila by direct fluorescence immunoassay (DFA) using FITC-labeled monoclonal antibodies targeting serogroups 1, 2, 4 and 6. QPCR was utilized for detection of Legionella spp. in the same samples. Counts of L. pneumophila from DFA and of Legionella spp. from qPCR were normalized to cells/L tower water. Concentrations were similar between grab and PMACS samples collected throughout the study by DFA analysis (P = 0.4461; repeated measures ANOVA). The same trend was observed with qPCR. However, PMACS concentration proved advantageous over membrane filtration by providing larger volume, more representative samples of the cooling tower environment, which led to reduced variability among sampling events and increasing the probability of detection of low level targets. These data highlight the utility of the PMACS for enhanced surveillance of L. pneumophila by providing improved sampling of the cooling tower environment.

  10. Sequencing illustrates the transcriptional response of Legionella pneumophila during infection and identifies seventy novel small non-coding RNAs.

    LENUS (Irish Health Repository)

    Weissenmayer, Barbara A

    2011-01-01

    Second generation sequencing has prompted a number of groups to re-interrogate the transcriptomes of several bacterial and archaeal species. One of the central findings has been the identification of complex networks of small non-coding RNAs that play central roles in transcriptional regulation in all growth conditions and for the pathogen\\'s interaction with and survival within host cells. Legionella pneumophila is a gram-negative facultative intracellular human pathogen with a distinct biphasic lifestyle. One of its primary environmental hosts in the free-living amoeba Acanthamoeba castellanii and its infection by L. pneumophila mimics that seen in human macrophages. Here we present analysis of strand specific sequencing of the transcriptional response of L. pneumophila during exponential and post-exponential broth growth and during the replicative and transmissive phase of infection inside A. castellanii. We extend previous microarray based studies as well as uncovering evidence of a complex regulatory architecture underpinned by numerous non-coding RNAs. Over seventy new non-coding RNAs could be identified; many of them appear to be strain specific and in configurations not previously reported. We discover a family of non-coding RNAs preferentially expressed during infection conditions and identify a second copy of 6S RNA in L. pneumophila. We show that the newly discovered putative 6S RNA as well as a number of other non-coding RNAs show evidence for antisense transcription. The nature and extent of the non-coding RNAs and their expression patterns suggests that these may well play central roles in the regulation of Legionella spp. specific traits and offer clues as to how L. pneumophila adapts to its intracellular niche. The expression profiles outlined in the study have been deposited into Genbank\\'s Gene Expression Omnibus (GEO) database under the series accession GSE27232.

  11. Enhanced chlorine resistance of tap water-adapted Legionella pneumophila as compared with agar medium-passaged strains.

    Science.gov (United States)

    Kuchta, J M; States, S J; McGlaughlin, J E; Overmeyer, J H; Wadowsky, R M; McNamara, A M; Wolford, R S; Yee, R B

    1985-07-01

    Previous studies have shown that bacteria maintained in a low-nutrient "natural" environment such as swimming pool water are much more resistant to disinfection by various chemical agents than strains maintained on rich media. In the present study a comparison was made of the chlorine (Cl2) susceptibility of hot-water tank isolates of Legionella pneumophila maintained in tap water and strains passaged on either nonselective buffered charcoal-yeast extract or selective differential glycine-vancomycin-polymyxin agar medium. Our earlier work has shown that environmental and clinical isolates of L. pneumophila maintained on agar medium are much more resistant to Cl2 than coliforms are. Under the present experimental conditions (21 degrees C, pH 7.6 to 8.0, and 0.25 mg of free residual Cl2 per liter, we found the tap water-maintained L. pneumophila strains to be even more resistant than the agar-passaged isolates. Under these conditions, 99% kill of tap water-maintained strains of L. pneumophila was usually achieved within 60 to 90 min compared with 10 min for agar-passaged strains. Samples from plumbing fixtures in a hospital yielded legionellae which were "super"-chlorine resistant when assayed under natural conditions. After one agar passage their resistance dropped to levels of comparable strains which had not been previously exposed to additional chlorination. These studies more closely approximate natural conditions than our previous work and show that tap water-maintained L. pneumophila is even more resistant to Cl2 than its already resistant agar medium-passaged counterpart.

  12. Incubation of premise plumbing water samples on Buffered Charcoal Yeast Extract agar at elevated temperature and pH selects for Legionella pneumophila.

    Science.gov (United States)

    Veenendaal, Harm R; Brouwer-Hanzens, Anke J; van der Kooij, Dick

    2017-10-15

    Worldwide, over 90% of the notified cases of Legionnaires' disease are caused by Legionella pneumophila. However, the standard culture medium for the detection of Legionella in environmental water samples, Buffered Charcoal Yeast Extract (BCYE) agar of pH 6.9 ± 0.4 with or without antimicrobial agents incubated at 36 ± 1 °C, supports the growth of a large diversity of Legionella species. BCYE agar of elevated pH or/and incubation at elevated temperature gave strongly reduced recoveries of most of 26 L. non-pneumophila spp. tested, but not of L. pneumophila. BCYE agar of pH 7.3 ± 0.1, incubated at 40 ± 0.5 °C (BCYE pH 7.3/40 °C) was tested for selective enumeration of L. pneumophila. Of the L. non-pneumophila spp. tested, only L. adelaidensis and L. londiniensis multiplied under these conditions. The colony counts on BCYE pH 7.3/40 °C of a L. pneumophila serogroup 1 strain cultured in tap water did not differ significantly from those on BCYE pH 6.9/36 °C when directly plated and after membrane filtration and showed repeatability's of 13-14%. By using membrane filtration L. pneumophila was detected in 58 (54%) of 107 Legionella-positive water samples from premise plumbing systems under one or both of these culture conditions. The L. pneumophila colony counts (log-transformed) on BCYE pH 7.3/40 °C were strongly related (r 2  = 0.87) to those on BCYE pH 6.9/36 °C, but differed significantly (p < 0.05) by a mean of - 0.12 ± 0.30 logs. L. non-pneumophila spp. were detected only on BCYE pH 6.9/36 °C in 49 (46%) of the samples. Hence, BCYE pH 7.3/40 °C can facilitate the enumeration of L. pneumophila and their isolation from premise plumbing systems with culturable L. non-pneumophila spp., some of which, e.g. L. anisa, can be present in high numbers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. [Investigation of Legionella pneumophila seropositivity in the professional long distance drivers as a risky occupation].

    Science.gov (United States)

    Polat, Yusuf; Ergin, Cağri; Kaleli, Ilknur; Pinar, Ahmet

    2007-04-01

    Contaminated water sources, reservoirs and systems such as evaporative condensers of air-conditioners are known to be the main transmission routes of Legionella spp. which are ubiquitous aquatic bacteria. By virtue of this point the aim of this study was to investigate the rate of Legionella pneumophila seropositivity in a profession considered as risky due to the direct and prolonged exposure to air-conditioning and air-circulating systems. For this purpose, in the period of February-August 2004 a total of 79 male subjects (63 were bus drivers and 16 were driver assistants) who were continously travelling to two different route (South part as hot climate and Middle/North parts as cold climate of Turkey) from Denizli province coach station (a province located in internal Aegian where accepted as crossroads), were included to the study. The mean age and mean working duration of bus drivers were 43.0 +/- 1.1 years and 20.0 +/- 1.1 years, respectively, while these values were 22.5 +/- 0.9 years and 4.0 +/- 0.6 years, respectively, for the drivers' assistants. The serum samples collected from the subjects were screened by a commercial indirect immunofluorescence method (Euroimmun, Germany) using L. pneumophila serogrup 1-14 antigens for the presence of specific antibodies. Additionally, air-conditioners' moisture exhaust samples of the busses in which seropositive subjects travelling with have been examined by culture and 5S rRNA gene targeted polymerase chain reaction (PCR) methods, for the presence of Legionella spp. The overall L. pneumophila seropositivity rate was detected as 15.2% (12/79). This rate was 19% (12/63) for bus drivers while all of the drivers' assistants were found seronegative. The seropositivity rate was found statistically higher in the personnel who were travelling to the hot climates (10/36, 27.8%) than those who travel to cold climates (2/43, 4.6%), (p travel. Our data indicated that long distance bus drivers were chronically exposed to this

  14. Zakażenia pałeczkami Legionella pneumophila – opis przypadku

    Directory of Open Access Journals (Sweden)

    Bolesław Kalicki

    2011-12-01

    Full Text Available Legionella pneumophila jest wewnątrzkomórkowym patogenem zasiedlającym środowiska wodne. Do zakażenia dochodzi drogą inhalacji zakażonego aerozolu, rzadziej poprzez aspirację. Rozprzestrzenianie się zachodzi drogą krwionośną, limfatyczną i przez ciągłość. Choroba rozwija się w postaci dwóch klinicznie odrębnych zespołów: choroby legionistów i gorączki Pontiac. Pozapłucne postaci legionelozy spotyka się niezmiernie rzadko. Powikłania mogą występować w postaci niedodmy, wysięku, zrostów, ropni płuc, ropniaków opłucnej, przetok oskrzelowo-opłucnowych, a w konsekwencji mogą prowadzić do niewydolności wielonarządowej. W diagnostyce zakażenia Legionella pneumophila stosuje się izolację i hodowlę bakterii uzyskanych z tkanek chorego na specjalnych podłożach, metody genetyczne bądź też testy serologiczne. W leczeniu skuteczne są antybiotyki z grupy makrolidów, a w ciężkiej postaci choroby także fluorochinolony. Leczeniem alternatywnym jest kombinacja trimetoprym + sulfametoksazol. W artykule przedstawiono opis przypadku 14-letniego chłopca, który został przyjęty do Kliniki z powodu gorączki, osłabienia, wymiotów, bólów brzucha i głowy. U dziecka wykonano serię badań wyjaśniających przyczynę dolegliwości. Stwierdzono podwyższone wykładniki stanu zapalnego z towarzyszącą leukopenią i trombocytopenią. W przebiegu choroby pojawiły się kaszel i wysypka. W badaniach dodatkowych wysunięto podejrzenie zajęcia układu sercowo-naczyniowego. Podejrzewając zakażenie atypowe, do leczenia dołączono makrolid, po którym uzyskano poprawę stanu klinicznego i ustąpienie objawów. Otrzymany później wynik badania w kierunku Legionella pneumophila wskazywał na możliwość zakażenia o tej etiologii.

  15. Coxsackievirus mutants that can bypass host factor PI4KIIIbeta and the need for high levels of PI4P lipids for replication

    NARCIS (Netherlands)

    van der Schaar, H.M.; van der Linden, L.; Lanke, K.H.W.; Strating, J.R.P.M.; Purstinger, G.; Vries, E. De; de Haan, C.A.; Neyts, J.; Kuppeveld, F.J.M. van

    2012-01-01

    RNA viruses can rapidly mutate and acquire resistance to drugs that directly target viral enzymes, which poses serious problems in a clinical context. Therefore, there is a growing interest in the development of antiviral drugs that target host factors critical for viral replication, since they are

  16. A STUDY ON LEGIONELLA PNEUMOPHILA, WATER CHEMISTRY, AND ATMOSPHERIC CONDITIONS IN COOLING TOWERS AT THE SAVANNAH RIVER SITE

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.; Brigmon, R.

    2009-10-20

    Legionnaires disease is a pneumonia caused by the inhalation of the bacterium Legionella pneumophila. The majority of illnesses have been associated with cooling towers since these devices can harbor and disseminate the bacterium in the aerosolized mist generated by these systems. Historically, Savannah River Site (SRS) cooling towers have had occurrences of elevated levels of Legionella in all seasons of the year and in patterns that are difficult to predict. Since elevated Legionella in cooling tower water are a potential health concern a question has been raised as to the best control methodology. In this work we analyze available chemical, biological, and atmospheric data to determine the best method or key parameter for control. The SRS 4Q Industrial Hygiene Manual, 4Q-1203, 1 - G Cooling Tower Operation and the SRNL Legionella Sampling Program, states that 'Participation in the SRNL Legionella Sampling Program is MANDATORY for all operating cooling towers'. The resulting reports include L. pneumophila concentration information in cells/L. L. pneumophila concentrations >10{sup 7} cells/L are considered elevated and unsafe so action must be taken to reduce these densities. These remedial actions typically include increase biocide addition or 'shocking'. Sometimes additional actions are required if the problem persists including increase tower maintenance (e.g. cleaning). Evaluation of 14 SRS cooling towers, seven water quality parameters, and five Legionella serogroups over a three-plus year time frame demonstrated that cooling tower water Legionella densities varied widely though out this time period. In fact there was no one common consistent significant variable across all towers. The significant factors that did show up most frequently were related to suspended particulates, conductivity, pH, and dissolved oxygen, not chlorine or bromine as might be expected. Analyses of atmospheric data showed that there were more frequent significant

  17. Master manipulators: an update on Legionella pneumophila Icm/Dot translocated substrates and their host targets

    Science.gov (United States)

    Isaac, Dervla T; Isberg, Ralph

    2014-01-01

    Macrophages are the front line of immune defense against invading microbes. Microbes, however, have evolved numerous and diverse mechanisms to thwart these host immune defenses and thrive intracellularly. Legionella pneumophila, a Gram-negative pathogen of amoebal and mammalian phagocytes, is one such microbe. In humans, it causes a potentially fatal pneumonia referred to as Legionnaires' disease. Armed with the Icm/Dot type IV secretion system, which is required for virulence, and approximately 300 translocated proteins, Legionella is able to enter host cells, direct the biogenesis of its own vacuolar compartment, and establish a replicative niche, where it grows to high levels before lysing the host cell. Efforts to understand the pathogenesis of this bacterium have focused on characterizing the molecular activities of its many effectors. In this article, we highlight recent strides that have been made in understanding how Legionella effectors mediate host-pathogen interactions. PMID:24762308

  18. SPR based immunosensor for detection of Legionella pneumophila in water samples

    Science.gov (United States)

    Enrico, De Lorenzis; Manera, Maria G.; Montagna, Giovanni; Cimaglia, Fabio; Chiesa, Maurizio; Poltronieri, Palmiro; Santino, Angelo; Rella, Roberto

    2013-05-01

    Detection of legionellae by water sampling is an important factor in epidemiological investigations of Legionnaires' disease and its prevention. To avoid labor-intensive problems with conventional methods, an alternative, highly sensitive and simple method is proposed for detecting L. pneumophila in aqueous samples. A compact Surface Plasmon Resonance (SPR) instrumentation prototype, provided with proper microfluidics tools, is built. The developed immunosensor is capable of dynamically following the binding between antigens and the corresponding antibody molecules immobilized on the SPR sensor surface. A proper immobilization strategy is used in this work that makes use of an important efficient step aimed at the orientation of antibodies onto the sensor surface. The feasibility of the integration of SPR-based biosensing setups with microfluidic technologies, resulting in a low-cost and portable biosensor is demonstrated.

  19. Comparison of five methods for extraction of Legionella pneumophila from respiratory specimens.

    Science.gov (United States)

    Wilson, Deborah; Yen-Lieberman, Belinda; Reischl, Udo; Warshawsky, Ilka; Procop, Gary W

    2004-12-01

    The efficiencies of five commercially available nucleic acid extraction methods were evaluated for the recovery of a standardized inoculum of Legionella pneumophila in respiratory specimens (sputum and bronchoalveolar lavage [BAL] specimens). The concentrations of Legionella DNA recovered from sputa with the automated MagNA Pure (526,200 CFU/ml) and NucliSens (171,800 CFU/ml) extractors were greater than those recovered with the manual methods (i.e., Roche High Pure kit [133,900 CFU/ml], QIAamp DNA Mini kit [46,380 CFU/ml], and ViralXpress kit [13,635 CFU/ml]). The rank order was the same for extracts from BAL specimens, except that for this specimen type the QIAamp DNA Mini kit recovered more than the Roche High Pure kit.

  20. Genetic variability in environmental isolates of Legionella pneumophila from Comunidad Valenciana (Spain).

    Science.gov (United States)

    Coscollá, Mireia; Gosalbes, María José; Catalán, Vicente; González-Candelas, Fernando

    2006-06-01

    Legionella pneumophila is associated to recurrent outbreaks in several Comunidad Valenciana (Spain) localities, especially in Alcoi, where social and climatic conditions seem to provide an excellent environment for bacterial growth. We have analysed the nucleotide sequences of three loci from 25 environmental isolates from Alcoi and nearby locations sampled over 3 years. The analysis of these isolates has revealed a substantial level of genetic variation, with consistent patterns of variability across loci, and comparable to that found in a large, European-wide sampling of clinical isolates. Among the tree loci studied, fliC showed the highest level of nucleotide diversity. The analysis of isolates sampled in different years revealed a clear differentiation, with samples from 2001 being significantly distinct from those obtained in 2002 and 2003. Furthermore, although linkage disequilibrium measures indicate a clonal nature for population structure in this sample, the presence of some recombination events cannot be ruled out.

  1. Legionella pneumophila infection of Drosophila S2 cells induces only minor changes in mitochondrial dynamics.

    Directory of Open Access Journals (Sweden)

    Elizabeth Wen Sun

    Full Text Available During infection of cells by Legionella pneumophila, the bacterium secretes a large number of effector proteins into the host cell cytoplasm, allowing it to alter many cellular processes and make the vacuole and the host cell into more hospitable environments for bacterial replication. One major change induced by infection is the recruitment of ER-derived vesicles to the surface of the vacuole, where they fuse with the vacuole membrane and prevent it from becoming an acidified, degradative compartment. However, the recruitment of mitochondria to the region of the vacuole has also been suggested by ultrastructural studies. In order to test this idea in a controlled and quantitative experimental system, and to lay the groundwork for a genome-wide screen for factors involved in mitochondrial recruitment, we examined the behavior of mitochondria during the early stages of Legionella pneumophila infection of Drosophila S2 cells. We found that the density of mitochondria near vacuoles formed by infection with wild type Legionella was not different from that found in dotA(- mutant-infected cells during the first 4 hours after infection. We then examined 4 parameters of mitochondrial motility in infected cells: velocity of movement, duty cycle of movement, directional persistence and net direction. In the 4 hours following infection, most of these measures were indistinguishable between wild type and dotA(-.infection. However, wild type Legionella did induce a modest shift in the velocity distribution toward faster movement compared dotA(- infection, and a small downward shift in the duty cycle distribution. In addition, wild type infection produced mitochondrial movement that was biased in the direction of the bacterial vacuole relative to dotA-, although not enough to cause a significant accumulation within 10 um of the vacuole. We conclude that in this host cell, mitochondria are not strongly recruited to the vacuole, nor is their motility

  2. Dendrimers and polyamino-phenolic ligands: activity of new molecules against Legionella pneumophila biofilms.

    Directory of Open Access Journals (Sweden)

    Elisa eAndreozzi

    2016-03-01

    Full Text Available Legionnaires’ disease is a potentially fatal pneumonia caused by Legionella pneumophila, an aquatic bacterium often found within the biofilm niche. In man-made water systems microbial biofilms increase the resistance of legionella to disinfection, posing a significant threat to public health. Disinfection methods currently used in water systems have been shown to be ineffective against legionella over the long-term, allowing recolonization by the biofilm-protected microorganisms. In this study, the anti-biofilm activity of previously fabricated polyamino-phenolic ligands and polyamidoamine dendrimers was investigated against legionella mono-species and multi-species biofilms formed by L. pneumophila in association with other bacteria that can be found in tap water (Aeromonas hydrophila, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae. Bacterial ability to form biofilms was verified using a crystal violet colorimetric assay and testing cell viability by real-time quantitative PCR and Plate Count assay. The concentration of the chemicals tested as anti-biofilm agents was chosen based on cytotoxicity assays: the highest non-cytotoxic chemical concentration was used for biofilm inhibition assays, with dendrimer concentration ten-fold higher than polyamino-phenolic ligands. While Macrophen and Double Macrophen were the most active substances among polyamino-phenolic ligands, dendrimers were overall two-fold more effective than all other compounds with a reduction up to 85% and 73% of legionella and multi-species biofilms, respectively. Chemical interaction with matrix molecules is hypothesized, based on SEM images and considering the low or absent anti-microbial activity on planktonic bacteria showed by flow cytometry. These data suggest that the studied compounds, especially dendrimers, could be considered as novel molecules in the design of research projects aimed at the development of efficacious anti-biofilm disinfection

  3. [Community-acquired pneumonia due to Legionella pneumophila serogroup 1. Study of 97 cases].

    Science.gov (United States)

    Benito, José Ramón; Montejo, José Miguel; Cancelo, Laura; Zalacaín, Rafael; López, Leyre; Fernández Gil de Pareja, Joaquín; Alonso, Eva; Oñate, Javier

    2003-10-01

    Legionella pneumophila is the causal agent of 5% to 12% of sporadic community-acquired pneumonia cases, though rates are changing with the use of new diagnostic methods. This is a retrospective study of all patients admitted to our hospital with community-acquired pneumonia due to Legionella pneumophila between 1997 and 2001. Diagnostic criteria included either a positive Legionella serogroup 1 urinary antigen test or seroconversion and a chest radiograph consistent with pneumonia. A total of 97 patients were studied. Ninety cases (92.8%) were community-acquired and 7 (7.2%) were associated with travelling. In 82 cases (84.5%) the presentation was sporadic. Seventy-five patients were smokers (77.3%). The most common symptoms were fever in 91 patients (93.8%) and cough in 67 (68.1%). In five patients (5.2%) creatine phosphokinase concentrations were over 5 times their baseline values (in two over 100 times); four of these patients presented acute renal failure. Seroconversion was observed in 23/42 patients (54.8%). There were no statistically significant differences between the administration of erythromycin or clarithromycin in monotherapy, or in combination with rifampin. Nineteen patients (19.6%) presented acute renal failure and mechanical ventilation was necessary in 22 (22.7%). Twelve patients died (12.5%). Independent prognostic factors associated with death included respiratory rate > 30 breaths/min, urea > 60 mg/dL and PaO2 scale scores and the presence of complications or mortality. The Legionella urinary antigen test permits early diagnosis and treatment of this disease. The severity scale is an indicator of complications or death.

  4. A Preliminary study on the prevalence of Legionella pneumophila infection in Lebanon

    International Nuclear Information System (INIS)

    Hamze, M.; Mallat, H.; Mokhbat, J.

    2009-01-01

    After the first outbreak of Legionnaire disease was described for the first time in1976, legionellosis has been increasingly recognized in association with many outbreaks, both community and hospital acquired. This disease remains a model of water borne transmission. In Lebanon, no report has yet been published on the prevalence of Legionella pneumophila infections. This study aims to evaluate the prevalence of legionellosis in hospitalized patients with community acquired pneumonia (CAP) and in patients with nosocomial pneumonia (HAP). The study was conducted between April 2004 and August 2007. Eleven community hospitals participated to this endeavour. Laboratory evaluation was conducted in two centers (Middle East Health Institute, Bsalim, Lebanon and Nini Hospital, Tripoli, Lebanon). Two hundred and forty two urinary samples and ninety one pulmonary samples from 242 patients were analyzed. The age range was 16 to 71 years. Two hundred and fifteen were from community acquired pneumonias and twenty seven were nosocomially acquired in intensive care units. The urinary antigen was investigated in 242 patients; the Binax kit ® was used in this research. In lung secretions of 91 patients, the presence of Legionella pneumophila was searched for using direct immunofluorescence method and culture. Among the 215 urinary samples from patients with CAP, three were positive for Legionella antigen with a prevalence of 1.4 %. Among the 27 patients with HAP, one was positive for Legionella antigen with a prevalence of 3.7%. This preliminary study reveals the fact that legionellosis is indeed present in Lebanon, hence the importance of considering it in the work-up and the management of patients with pneumonia. Hospital laboratories should therefore routin ely search for this pathogen through at least urinary antigen detection. Health authorities should also enforce microbiological regulations concerning water sanitation in hospitals and in the community to prevent the

  5. Teotihuacan, tepeapulco, and obsidian exploitation.

    Science.gov (United States)

    Charlton, T H

    1978-06-16

    Current cultural ecological models of the development of civilization in central Mexico emphasize the role of subsistence production techniques and organization. The recent use of established and productive archeological surface survey techniques along natural corridors of communication between favorable niches for cultural development within the Central Mexican symbiotic region resulted in the location of sites that indicate an early development of a decentralized resource exploitation, manufacturing, and exchange network. The association of the development of this system with Teotihuacán indicates the importance such nonsubsistence production and exchange had in the evolution of this first central Mexican civilization. The later expansion of Teotihuacán into more distant areas of Mesoamerica was based on this resource exploitation model. Later civilizations centered at Tula and Tenochtitlán also used such a model in their expansion.

  6. Network exploitation using WAMI tracks

    Science.gov (United States)

    Rimey, Ray; Record, Jim; Keefe, Dan; Kennedy, Levi; Cramer, Chris

    2011-06-01

    Creating and exploiting network models from wide area motion imagery (WAMI) is an important task for intelligence analysis. Tracks of entities observed moving in the WAMI sensor data are extracted, then large numbers of tracks are studied over long time intervals to determine specific locations that are visited (e.g., buildings in an urban environment), what locations are related to other locations, and the function of each location. This paper describes several parts of the network detection/exploitation problem, and summarizes a solution technique for each: (a) Detecting nodes; (b) Detecting links between known nodes; (c) Node attributes to characterize a node; (d) Link attributes to characterize each link; (e) Link structure inferred from node attributes and vice versa; and (f) Decomposing a detected network into smaller networks. Experimental results are presented for each solution technique, and those are used to discuss issues for each problem part and its solution technique.

  7. Assessment of intercentre reproducibility and epidemiological concordance of Legionella pneumophila serogroup 1 genotyping by amplified fragment length polymorphism analysis

    DEFF Research Database (Denmark)

    Fry, N K; Bangsborg, Jette Marie; Bernander, S

    2000-01-01

    The aims of this work were to assess (i) the intercentre reproducibility and epidemiological concordance of amplified fragment length polymorphism analysis for epidemiological typing of Legionella pneumophila serogroup 1, and (ii) the suitability of the method for standardisation and implementation...... by members of the European Working Group on Legionella Infections. Fifty coded isolates comprising two panels of well-characterised strains, a "reproducibility" panel (n=20) and an "epidemiologically related" panel (n=30), were sent to 13 centres in 12 European countries. Analysis was undertaken in each...... using gel analysis software yielded R=1.00 and E=1.00, with 12, 13 or 14 types. This method can be used as a simple, rapid screening tool for epidemiological typing of isolates of Legionella pneumophila serogroup 1. Results demonstrate that the method can be highly reproducible (R=1...

  8. Nucleotide sequence analysis of the Legionella micdadei mip gene, encoding a 30-kilodalton analog of the Legionella pneumophila Mip protein

    DEFF Research Database (Denmark)

    Bangsborg, Jette Marie; Cianciotto, N P; Hindersson, P

    1991-01-01

    After the demonstration of analogs of the Legionella pneumophila macrophage infectivity potentiator (Mip) protein in other Legionella species, the Legionella micdadei mip gene was cloned and expressed in Escherichia coli. DNA sequence analysis of the L. micdadei mip gene contained in the plasmid p...... homology with the mip-like genes of several Legionella species. Furthermore, amino acid sequence comparisons revealed significant homology to two eukaryotic proteins with isomerase activity (FK506-binding proteins)....

  9. Proteomic analysis of growth phase-dependent expression of Legionella pneumophila proteins which involves regulation of bacterial virulence traits.

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Hayashi

    Full Text Available Legionella pneumophila, which is a causative pathogen of Legionnaires' disease, expresses its virulent traits in response to growth conditions. In particular, it is known to become virulent at a post-exponential phase in vitro culture. In this study, we performed a proteomic analysis of differences in expression between the exponential phase and post-exponential phase to identify candidates associated with L. pneumophila virulence using 2-Dimentional Fluorescence Difference Gel Electrophoresis (2D-DIGE combined with Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometry (MALDI-TOF-MS. Of 68 identified proteins that significantly differed in expression between the two growth phases, 64 were up-regulated at a post-exponential phase. The up-regulated proteins included enzymes related to glycolysis, ketone body biogenesis and poly-3-hydroxybutyrate (PHB biogenesis, suggesting that L. pneumophila may utilize sugars and lipids as energy sources, when amino acids become scarce. Proteins related to motility (flagella components and twitching motility-associated proteins were also up-regulated, predicting that they enhance infectivity of the bacteria in host cells under certain conditions. Furthermore, 9 up-regulated proteins of unknown function were found. Two of them were identified as novel bacterial factors associated with hemolysis of sheep red blood cells (SRBCs. Another 2 were found to be translocated into macrophages via the Icm/Dot type IV secretion apparatus as effector candidates in a reporter assay with Bordetella pertussis adenylate cyclase. The study will be helpful for virulent analysis of L. pneumophila from the viewpoint of physiological or metabolic modulation dependent on growth phase.

  10. Comparative assessment of chlorine, heat, ozone, and UV light for killing Legionella pneumophila within a model plumbing system

    International Nuclear Information System (INIS)

    Muraca, P.; Stout, J.E.; Yu, V.L.

    1987-01-01

    Nosocomial Legionnaires disease can be acquired by exposure to the organism from the hospital water distribution system. As a result, many hospitals have instituted eradication procedures, including hypercholorination and thermal eradication. We compared the efficacy of ozonation, UV light, hyperchlorination, and heat eradication using a model plumbing system constructed of copper piping, brass spigots, Plexiglas reservoir, electric hot water tank, and a pump. Legionella pneumophila was added to the system at 10(7) CFU/ml. Each method was tested under three conditions; (i) nonturbid water at 25 degrees C, (ii) turbid water at 25 degrees C, and (iii) nonturbid water at 43 degrees C. UV light and heat killed L. pneumophila most rapidly and required minimal maintenance. Both UV light and heat (60 degrees C) produced a 5 log kill in less than 1 h. In contrast, both chlorine and ozone required 5 h of exposure to produce a 5 log decrease. Neither turbidity nor the higher temperature of 43 degrees C impaired the efficacy of any of the disinfectant methods. Surprisingly, higher temperature enhanced the disinfecting efficacy of chlorine. However, higher temperature accelerated the decomposition of the chlorine residual such that an additional 120% volume of chlorine was required. All four methods proved efficacious in eradicating L. pneumophila from a model plumbing system

  11. The ESA Geohazard Exploitation Platform

    Science.gov (United States)

    Bally, Philippe; Laur, Henri; Mathieu, Pierre-Philippe; Pinto, Salvatore

    2015-04-01

    Earthquakes represent one of the world's most significant hazards in terms both of loss of life and damages. In the first decade of the 21st century, earthquakes accounted for 60 percent of fatalities from natural disasters, according to the United Nations International Strategy for Disaster Reduction (UNISDR). To support mitigation activities designed to assess and reduce risks and improve response in emergency situations, satellite EO can be used to provide a broad range of geo-information services. This includes for instance crustal block boundary mapping to better characterize active faults, strain rate mapping to assess how rapidly faults are deforming, soil vulnerability mapping to help estimate how the soil is behaving in reaction to seismic phenomena, geo-information to assess the extent and intensity of the earthquake impact on man-made structures and formulate assumptions on the evolution of the seismic sequence, i.e. where local aftershocks or future main shocks (on nearby faults) are most likely to occur. In May 2012, the European Space Agency and the GEO Secretariat convened the International Forum on Satellite EO for Geohazards now known as the Santorini Conference. The event was the continuation of a series of international workshops such as those organized by the Geohazards Theme of the Integrated Global Observing Strategy Partnership. In Santorini the seismic community has set out a vision of the EO contribution to an operational global seismic risk program, which lead to the Geohazard Supersites and Natural Laboratories (GSNL) initiative. The initial contribution of ESA to suuport the GSNL was the first Supersites Exploitation Platform (SSEP) system in the framework of Grid Processing On Demand (GPOD), now followed by the Geohazard Exploitation Platform (GEP). In this presentation, we will describe the contribution of the GEP for exploiting satellite EO for geohazard risk assessment. It is supporting the GEO Supersites and has been further

  12. Efficacy of thermal treatment and copper-silver ionization for controlling Legionella pneumophila in high-volume hot water plumbing systems in hospitals.

    Science.gov (United States)

    Mietzner, S; Schwille, R C; Farley, A; Wald, E R; Ge, J H; States, S J; Libert, T; Wadowsky, R M; Miuetzner, S

    1997-12-01

    Thermal treatment and copper-silver ionization are often used for controlling Legionella pneumophila in high-volume hospital plumbing systems, although the comparative efficacies of these measures in high-volume systems are unknown. Thermal treatment of a hot water circuit was accomplished by flushing hot water (> 60 degrees C) through distal fixtures for 10 minutes. Copper-silver ionization was conducted in three circuits by installing units into return lines immediately upstream from hot water tanks. Recovery rates of L. pneumophila were monitored by culturing swab samples from faucets. Concentrations of copper and silver in water samples were determined by atomic absorption spectrophotometry. Four heat-flush treatments failed to provide long-term control of L. pneumophila. In contrast, ionization treatment reduced the rate of recovery of L. pneumophila from 108 faucets from 72% to 2% within 1 month and maintained effective control for at least 22 months. Only three samples (1.9%) of hot water from faucets exceeded Environmental Protection Agency standards for silver, and none exceeded the standards for copper. Of 24 samples obtained from hot water tanks, 42% and 50% exceeded the silver and copper standards, respectively. Copper-silver ionization effectively controls L. pneumophila in high-volume plumbing systems and is superior to thermal treatment; however, high concentrations of copper and silver can accumulate at the bottom of hot water tanks.

  13. Prospects of geothermal resource exploitation

    International Nuclear Information System (INIS)

    Bourrelier, P.H.; Cornet, F.; Fouillac, C.

    1994-01-01

    The use of geothermal energy to generate electricity has only occurred during the past 50 years by drilling wells in aquifers close to magmas and producing either dry steam or hot water. The world's production of electricity from geothermal energy is over 6000 MWe and is still growing. The direct use of geothermal energy for major urban communities has been developed recently by exploitation of aquifers in sedimentary basins under large towns. Scaling up the extraction of heat implies the exploitation of larger and better located fields requiring an appropriate method of extraction; the objective of present attempts in USA, Japan and Europe is to create heat exchangers by the circulation of water between several deep wells. Two field categories are considered: the extension of classical geothermal fields beyond the aquifer areas, and areas favoured by both a high geothermal gradient, fractures inducing a natural permeability at large scale, and good commercial prospects (such as in the Rhenan Graben). Hot dry rocks concept has gained a large interest. 1 fig., 5 tabs., 11 refs

  14. A new measure of interpersonal exploitativeness

    Directory of Open Access Journals (Sweden)

    Amy B. Brunell

    2013-05-01

    Full Text Available Measures of exploitativeness evidence problems with validity and reliability. The present set of studies assessed a new measure (the Interpersonal Exploitativeness Scale that defines exploitativeness in terms of reciprocity. In Studies 1 and 2, 33 items were administered to participants. Exploratory and Confirmatory Factor Analysis demonstrated that a single factor consisting of six items adequately assess interpersonal exploitativeness. Study 3 results revealed that the Interpersonal Exploitativeness Scale was positively associated with normal narcissism, pathological narcissism, psychological entitlement, and negative reciprocity and negatively correlated with positive reciprocity. In Study 4, participants competed in a commons dilemma. Those who scored higher on the Interpersonal Exploitativeness Scale were more likely to harvest a greater share of resources over time, even while controlling for other relevant variables, such as entitlement. Together, these studies show the Interpersonal Exploitativeness Scale to be a valid and reliable measure of interpersonal exploitativeness. The authors discuss the implications of these studies.

  15. Exploitation in International Paid Surrogacy Arrangements

    OpenAIRE

    Wilkinson, Stephen

    2015-01-01

    Abstract Many critics have suggested that international paid surrogacy is exploitative. Taking such concerns as its starting point, this article asks: (1) how defensible is the claim that international paid surrogacy is exploitative and what could be done to make it less exploitative? (2) In the light of the answer to (1), how strong is the case for prohibiting it? Exploitation could in principle be dealt with by improving surrogates' pay and conditions. However, doing so may exacerbate probl...

  16. The exploitation argument against commercial surrogacy.

    Science.gov (United States)

    Wilkinson, Stephen

    2003-04-01

    This paper discusses the exploitation argument against commercial surrogacy: the claim that commercial surrogacy is morally objectionable because it is exploitative. The following questions are addressed. First, what exactly does the exploitation argument amount to? Second, is commercial surrogacy in fact exploitative? Third, if it were exploitative, would this provide a sufficient reason to prohibit (or otherwise legislatively discourage) it? The focus throughout is on the exploitation of paid surrogates, although it is noted that other parties (e.g. 'commissioning parents') may also be the victims of exploitation. It is argued that there are good reasons for believing that commercial surrogacy is often exploitative. However, even if we accept this, the exploitation argument for prohibiting (or otherwise legislatively discouraging) commercial surrogacy remains quite weak. One reason for this is that prohibition may well 'backfire' and lead to potential surrogates having to do other things that are more exploitative and/or more harmful than paid surrogacy. It is concluded therefore that those who oppose exploitation should (rather than attempting to stop particular practices like commercial surrogacy) concentrate on: (a) improving the conditions under which paid surrogates 'work'; and (b) changing the background conditions (in particular, the unequal distribution of power and wealth) which generate exploitative relationships.

  17. The Exploitation of Evolving Resources

    CERN Document Server

    McGlade, Jacqueline; Law, Richard

    1993-01-01

    The impact of man on the biosphere is profound. Quite apart from our capacity to destroy natural ecosystems and to drive species to extinction, we mould the evolution of the survivors by the selection pressures we apply to them. This has implications for the continued health of our natural biological resources and for the way in which we seek to optimise yield from those resources. Of these biological resources, fish stocks are particularly important to mankind as a source of protein. On a global basis, fish stocks provide the major source of protein for human consumption from natural ecosystems, amounting to some seventy million tonnes in 1970. Although fisheries management has been extensively developed over the last century, it has not hitherto considered the evolutionary consequences of fishing activity. While this omission may not have been serious in the past, the ever increasing intensity of exploitation and the deteriorating health of fish stocks has generated an urgent need for a better understanding...

  18. Swedish mines. Underground exploitation methods

    International Nuclear Information System (INIS)

    Paucard, A.

    1960-01-01

    Between 1949 and 1957, 10 engineers of the Mining research and exploitation department of the CEA visited 17 Swedish mines during 5 field trips. This paper presents a compilation of the information gathered during these field trips concerning the different underground mining techniques used in Swedish iron mines: mining with backfilling (Central Sweden and Boliden mines); mining without backfilling (mines of the polar circle area). The following techniques are described successively: pillar drawing and backfilled slices (Ammeberg, Falun, Garpenberg, Boliden group), sub-level pillar drawing (Grangesberg, Bloettberget, Haeksberg), empty room and sub-level pillar drawing (Bodas, Haksberg, Stripa, Bastkarn), storage chamber pillar drawing (Bodas, Haeksberg, Bastkarn), and pillar drawing by block caving (ldkerberget). Reprint of a paper published in Revue de l'Industrie Minerale, vol. 41, no. 12, 1959 [fr

  19. Exploiting social evolution in biofilms

    DEFF Research Database (Denmark)

    Boyle, Kerry E; Heilmann, Silja; van Ditmarsch, Dave

    2013-01-01

    Bacteria are highly social organisms that communicate via signaling molecules, move collectively over surfaces and make biofilm communities. Nonetheless, our main line of defense against pathogenic bacteria consists of antibiotics-drugs that target individual-level traits of bacterial cells...... and thus, regrettably, select for resistance against their own action. A possible solution lies in targeting the mechanisms by which bacteria interact with each other within biofilms. The emerging field of microbial social evolution combines molecular microbiology with evolutionary theory to dissect...... the molecular mechanisms and the evolutionary pressures underpinning bacterial sociality. This exciting new research can ultimately lead to new therapies against biofilm infections that exploit evolutionary cheating or the trade-off between biofilm formation and dispersal....

  20. Energy for lunar resource exploitation

    Science.gov (United States)

    Glaser, Peter E.

    1992-02-01

    Humanity stands at the threshold of exploiting the known lunar resources that have opened up with the access to space. America's role in the future exploitation of space, and specifically of lunar resources, may well determine the level of achievement in technology development and global economic competition. Space activities during the coming decades will significantly influence the events on Earth. The 'shifting of history's tectonic plates' is a process that will be hastened by the increasingly insistent demands for higher living standards of the exponentially growing global population. Key to the achievement of a peaceful world in the 21st century, will be the development of a mix of energy resources at a societally acceptable and affordable cost within a realistic planning horizon. This must be the theme for the globally applicable energy sources that are compatible with the Earth's ecology. It is in this context that lunar resources development should be a primary goal for science missions to the Moon, and for establishing an expanding human presence. The economic viability and commercial business potential of mining, extracting, manufacturing, and transporting lunar resource based materials to Earth, Earth orbits, and to undertake macroengineering projects on the Moon remains to be demonstrated. These extensive activities will be supportive of the realization of the potential of space energy sources for use on Earth. These may include generating electricity for use on Earth based on beaming power from Earth orbits and from the Moon to the Earth, and for the production of helium 3 as a fuel for advanced fusion reactors.

  1. Inactivation kinetics and efficiencies of UV-LEDs against Pseudomonas aeruginosa, Legionella pneumophila, and surrogate microorganisms.

    Science.gov (United States)

    Rattanakul, Surapong; Oguma, Kumiko

    2018-03-01

    To demonstrate the effectiveness of UV light-emitting diodes (UV-LEDs) to disinfect water, UV-LEDs at peak emission wavelengths of 265, 280, and 300 nm were adopted to inactivate pathogenic species, including Pseudomonas aeruginosa and Legionella pneumophila, and surrogate species, including Escherichia coli, Bacillus subtilis spores, and bacteriophage Qβ in water, compared to conventional low-pressure UV lamp emitting at 254 nm. The inactivation profiles of each species showed either a linear or sigmoidal survival curve, which both fit well with the Geeraerd's model. Based on the inactivation rate constant, the 265-nm UV-LED showed most effective fluence, except for with E. coli which showed similar inactivation rates at 265 and 254 nm. Electrical energy consumption required for 3-log 10 inactivation (E E,3 ) was lowest for the 280-nm UV-LED for all microbial species tested. Taken together, the findings of this study determined the inactivation profiles and kinetics of both pathogenic bacteria and surrogate species under UV-LED exposure at different wavelengths. We also demonstrated that not only inactivation rate constants, but also energy efficiency should be considered when selecting an emission wavelength for UV-LEDs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Nosocomial infection with Legionella pneumophila serogroup 1 and 8 in a neonate.

    Science.gov (United States)

    Aubert, G; Bornstein, N; Rayet, I; Pozzetto, B; Lenormand, P H

    1990-01-01

    A case of pneumonia related to 2 serogroups (1 and 8) of Legionella pneumophila (Lp) in a 10-day-old boy is described together with the epidemiological survey in the maternity ward which made it possible to establish its nosocomial origin. Rodshaped bacteria reacting with an Lp genus-specific monoclonal antibody and serogroup 1 and 8 polyclonal sera were detected in bronchoalveolar lavages (BAL) collected on day 13. Serogroups 1 and 8 were recovered from cultures of BAL collected on days 12 and 13. Fourfold or more antibody rises to serogroups 1, 5, 8 and 10 of Lp were observed in sequential serum specimens. Water samples collected from the tank and mixer of the maternity ward grew serogroups 1 and 8 of Lp. Serogroup 1 was detected in large amounts in water samples taken at several points of the hot water supply system and from the oxygen nebulizers and the feeding-bottle heater. Analysis of the Lp serogroup 1 strains isolated from the water by subgroup-specific monoclonal antibodies revealed the presence of 4 different subgroups, one of which was identical to the Lp 1 subgroup isolated from the neonate's BAL. This latter subgroup, reactive with McKinney monoclonal antibody Mab 2, has been described as highly virulent. No other case of legionellosis was recorded in the maternity ward.

  3. Rate of Legionella pneumophila colonization in hospital hot water network after time flow taps installation.

    Science.gov (United States)

    Totaro, M; Valentini, P; Costa, A L; Giorgi, S; Casini, B; Baggiani, A

    2018-01-01

    In hospital water systems legionellae may be resistant to disinfectants in pipework, which is a problem particularly in areas where there is low flow or stagnation of water. We evaluated legionella colonization of a water network of an Italian hospital after time flow taps (TFTs) installation in proximity to dead legs. The water volume flushed was 64 L/day from May 2016, and 192 L/day from December 2016. Before TFTs installation, Legionella pneumophila sg2-14 was detected in all points (4 × 10 4  ± 3.1 × 10 4  cfu/L). All sites remained positive (2.9 × 10 4  ± 1.9 × 10 4  cfu/L) through November 2016. From December 2016 legionella persisted in one point only (2 × 10 2 to 6.8 × 10 3  cfu/L). TFTs with chemical disinfection may reduce legionella colonization associated with dead legs. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  4. Structural basis for Rab1 de-AMPylation by the Legionella pneumophila effector SidD.

    Directory of Open Access Journals (Sweden)

    Yang Chen

    Full Text Available The covalent attachment of adenosine monophosphate (AMP to proteins, a process called AMPylation (adenylylation, has recently emerged as a novel theme in microbial pathogenesis. Although several AMPylating enzymes have been characterized, the only known virulence protein with de-AMPylation activity is SidD from the human pathogen Legionella pneumophila. SidD de-AMPylates mammalian Rab1, a small GTPase involved in secretory vesicle transport, thereby targeting the host protein for inactivation. The molecular mechanisms underlying Rab1 recognition and de-AMPylation by SidD are unclear. Here, we report the crystal structure of the catalytic region of SidD at 1.6 Å resolution. The structure reveals a phosphatase-like fold with additional structural elements not present in generic PP2C-type phosphatases. The catalytic pocket contains a binuclear metal-binding site characteristic of hydrolytic metalloenzymes, with strong dependency on magnesium ions. Subsequent docking and molecular dynamics simulations between SidD and Rab1 revealed the interface contacts and the energetic contribution of key residues to the interaction. In conjunction with an extensive structure-based mutational analysis, we provide in vivo and in vitro evidence for a remarkable adaptation of SidD to its host cell target Rab1 which explains how this effector confers specificity to the reaction it catalyses.

  5. An alkaline approach to treating cooling towers for control of Legionella pneumophila.

    Science.gov (United States)

    States, S J; Conley, L F; Towner, S G; Wolford, R S; Stephenson, T E; McNamara, A M; Wadowsky, R M; Yee, R B

    1987-08-01

    Earlier field and laboratory studies have shown that Legionella species survive and multiply in the pH range 5.5 to 9.2. Additionally, the technical feasibility of operating cooling towers at elevated alkalinities and pH has previously been documented by published guidelines. The guidelines indicate that these conditions facilitate corrosion control and favor chlorine persistence which enhances the effectiveness of continuous chlorination in biofouling control. This information suggests that control of Legionella species in cooling towers can be accomplished by operating the towers under alkaline conditions. To test this possibility, we collected water samples over a period of months from a hospital cooling tower. The samples were analyzed for a variety of chemical parameters. Subsamples were pasteurized and inoculated with non-agar-passaged Legionella pneumophila which had been maintained in tap water. Correlation of subsequent Legionella growth with corresponding pH and alkalinity values revealed statistically significant inverse associations. These data support the hypothesis that operating cooling towers outside of the optimal conditions for Legionella growth (e.g., at elevated alkalinities and a pH greater than 9) may be a useful approach to controlling growth in this habitat.

  6. Hot water systems as sources of Legionella pneumophila in hospital and nonhospital plumbing fixtures

    Energy Technology Data Exchange (ETDEWEB)

    Wadowsky, R.M.; Yee, R.B.; Mezmar, L.; Wing, E.J.; Dowling, J.N.

    1982-05-01

    Samples obtained from plumbing systems of hospitals, nonhospital institutions, and homes were cultured for Legionella spp. by plating the samples directly on a selective medium. Swab samples were taken from the inner surfaces of faucet assemblies (aerators, spouts, and valve seats), showerheads, and shower pipes. Water and sediment were collected from the bottom of hot-water tanks. Legionella pnenumophila serogroups 1.5, and 6 were recovered from plubming fixtures of the hospitals and nonhospital institutions and one of five homes. The legionellae (7 to 13,850 colony-forming units per ml) were also present in water and sediment from hot-water tanks maintained at 30 to 54/sup 0/C, but not in those maintained at 71 and 77/sup 0/C. Legionella micdadei was isolated from one tank. Thus legionellae are present in hot-water tanks which are maintained at warm temperatures or whose design results in warm temperatures at the bottom of the tanks. We hypothesize that hot-water tanks are a breeding site and a major source of L. pneumophila for the contamination of plumbing systems. The existence of these bacteria in the plumbing systems and tanks was not necessarily associated with disease. The extent of the hazard of this contamination needs to be delineated.

  7. Alkaline approach to treating cooling towers for control of Legionella pneumophila

    Energy Technology Data Exchange (ETDEWEB)

    States, S.J.; Conley, L.F.; Towner, S.G.; Wolford, R.S.; Stephenson, T.E.; McNamara, M.; Wadowsky, R.M.; Yee, R.B.

    1987-08-01

    Earlier field and laboratory studies have shown that Legionella species survive and multiply in the pH range 5.5 to 9.2. Additionally, the technical feasibility of operating cooling towers at elevated alkalinities and pH has previously been documented by published guidelines. The guidelines indicate that these conditions facilitate corrosion control and favor chlorine persistence which enhances the effectiveness of continuous chlorination in biofouling control. This information suggest that control of Legionella species in cooling towers can be accomplished by operating the towers under alkaline conditions. To test this possibility, we collected water samples over a period of months from a hospital cooling tower. The samples were analyzed for a variety of chemical parameters. Subsamples were pasteurized and inoculated with non-agar-passaged Legionella pneumophila which had been maintained in tap water. Correlation of subsequent Legionella growth with corresponding pH and alkalinity values revealed statistically significant inverse associations. These data support the hypothesis that operating cooling towers outside of the optimal conditions for Legionella growth (e.g., at elevated alkalinities and a pH greater than 9) may be a useful approach to controlling growth in this habitat.

  8. First Case of Legionnaire's Disease Caused by Legionella anisa in Spain and the Limitations on the Diagnosis of Legionella non-pneumophila Infections.

    Science.gov (United States)

    Vaccaro, Lucianna; Izquierdo, Fernando; Magnet, Angela; Hurtado, Carolina; Salinas, Mireya B; Gomes, Thiago Santos; Angulo, Santiago; Salso, Santiago; Pelaez, Jesús; Tejeda, Maria Isabel; Alhambra, Almudena; Gómez, Carmen; Enríquez, Ana; Estirado, Eva; Fenoy, Soledad; Del Aguila, Carmen

    2016-01-01

    Legionnaires' disease is a severe form of pneumonia, with worldwide relevance, caused by Legionella spp. Approximately 90% of all cases of legionellosis are caused by Legionella pneumophila, but other species can also be responsible for this infection. These bacteria are transmitted by inhalation of aerosols or aspiration of contaminated water. In Spain, environmental studies have demonstrated the presence of Legionella non-pneumophila species in drinking water treatment plants and water distribution networks. Aware that this evidence indicates a risk factor and the lack of routine assays designed to detect simultaneously diverse Legionella species, we analyzed 210 urine samples from patients presenting clinical manifestations of pneumonia using a semi-nested PCR for partial amplification of the 16S rDNA gene of Legionella and a diagnostic method used in hospitals for Legionella antigen detection. In this study, we detected a total of 15 cases of legionellosis (7.1%) and the first case of Legionnaires' disease caused by L. anisa in Spain. While the conventional method used in hospitals could only detect four cases (1.9%) produced by L. pneumophila serogroup 1, using PCR, the following species were identified: Legionella spp. (10/15), L. pneumophila (4/15) and L. anisa (1/15). These results suggest the need to change hospital diagnostic strategies regarding the identification of Legionella species associated with this disease. Therefore, the detection of Legionella DNA by PCR in urine samples seems to be a suitable alternative method for a sensitive, accurate and rapid diagnosis of Legionella pneumonia, caused by L. pneumophila and also for L. non-pneumophila species.

  9. Usefulness of real-time PCR as a complementary tool to the monitoring of Legionella spp. and Legionella pneumophila by culture in industrial cooling systems.

    Science.gov (United States)

    Touron-Bodilis, A; Pougnard, C; Frenkiel-Lebossé, H; Hallier-Soulier, S

    2011-08-01

    This study was designed to evaluate the usefulness of quantification by real-time PCR as a management tool to monitor concentrations of Legionella spp. and Legionella pneumophila in industrial cooling systems and its ability to anticipate culture trends by the French standard method (AFNOR T90-431). Quantifications of Legionella bacteria were achieved by both methods on samples from nine cooling systems with different water qualities. Proportion of positive samples for L. pneumophila quantified by PCR was clearly lower in deionized or river waters submitted to a biocide treatment than in raw river waters, while positive samples for Legionella spp. were quantified for almost all the samples. For some samples containing PCR inhibitors, high quantification limits (up to 4·80 × 10(5) GU l(-1) ) did not allow us to quantify L. pneumophila, when they were quantified by culture. Finally, the monitoring of concentrations of L. pneumophila by both methods showed similar trends for 57-100% of the samples. These results suggest that, if some methodological steps designed to reduce inhibitory problems and thus decrease the quantification limits, could be developed to quantify Legionella in complex waters, the real-time PCR could be a valuable complementary tool to monitor the evolution of L. pneumophila concentrations. This study shows the possibility of using real-time PCR to monitor L. pneumophila proliferations in cooling systems and the importance to adapt nucleic acid extraction and purification protocols to raw waters. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology. No claim to French Government works.

  10. Evaluation of an Optimal Epidemiological Typing Scheme for Legionella pneumophila with Whole-Genome Sequence Data Using Validation Guidelines.

    Science.gov (United States)

    David, Sophia; Mentasti, Massimo; Tewolde, Rediat; Aslett, Martin; Harris, Simon R; Afshar, Baharak; Underwood, Anthony; Fry, Norman K; Parkhill, Julian; Harrison, Timothy G

    2016-08-01

    Sequence-based typing (SBT), analogous to multilocus sequence typing (MLST), is the current "gold standard" typing method for investigation of legionellosis outbreaks caused by Legionella pneumophila However, as common sequence types (STs) cause many infections, some investigations remain unresolved. In this study, various whole-genome sequencing (WGS)-based methods were evaluated according to published guidelines, including (i) a single nucleotide polymorphism (SNP)-based method, (ii) extended MLST using different numbers of genes, (iii) determination of gene presence or absence, and (iv) a kmer-based method. L. pneumophila serogroup 1 isolates (n = 106) from the standard "typing panel," previously used by the European Society for Clinical Microbiology Study Group on Legionella Infections (ESGLI), were tested together with another 229 isolates. Over 98% of isolates were considered typeable using the SNP- and kmer-based methods. Percentages of isolates with complete extended MLST profiles ranged from 99.1% (50 genes) to 86.8% (1,455 genes), while only 41.5% produced a full profile with the gene presence/absence scheme. Replicates demonstrated that all methods offer 100% reproducibility. Indices of discrimination range from 0.972 (ribosomal MLST) to 0.999 (SNP based), and all values were higher than that achieved with SBT (0.940). Epidemiological concordance is generally inversely related to discriminatory power. We propose that an extended MLST scheme with ∼50 genes provides optimal epidemiological concordance while substantially improving the discrimination offered by SBT and can be used as part of a hierarchical typing scheme that should maintain backwards compatibility and increase discrimination where necessary. This analysis will be useful for the ESGLI to design a scheme that has the potential to become the new gold standard typing method for L. pneumophila. Copyright © 2016 David et al.

  11. Phenylalanine hydroxylase from Legionella pneumophila is a thermostable enzyme with a major functional role in pyomelanin synthesis.

    Directory of Open Access Journals (Sweden)

    Marte I Flydal

    Full Text Available Legionella pneumophila is a pathogenic bacterium that can cause Legionnaires' disease and other non-pneumonic infections in humans. This bacterium produces a pyomelanin pigment, a potential virulence factor with ferric reductase activity. In this work, we have investigated the role of phenylalanine hydroxylase from L. pneumophila (lpPAH, the product of the phhA gene, in the synthesis of the pyomelanin pigment and the growth of the bacterium in defined compositions.Comparative studies of wild-type and phhA mutant corroborate that lpPAH provides the excess tyrosine for pigment synthesis. phhA and letA (gacA appear transcriptionally linked when bacteria were grown in buffered yeast extract medium at 37°C. phhA is expressed in L. pneumophila growing in macrophages. We also cloned and characterized lpPAH, which showed many characteristics of other PAHs studied so far, including Fe(II requirement for activity. However, it also showed many particular properties such as dimerization, a high conformational thermal stability, with a midpoint denaturation temperature (T(m = 79 ± 0.5°C, a high specific activity at 37°C (10.2 ± 0.3 µmol L-Tyr/mg/min and low affinity for the substrate (K(m (L-Phe = 735 ± 50 µM.lpPAH has a major functional role in the synthesis of pyomelanin and promotes growth in low-tyrosine media. The high thermal stability of lpPAH might reflect the adaptation of the enzyme to withstand relatively high survival temperatures.

  12. Exploiting Symmetry on Parallel Architectures.

    Science.gov (United States)

    Stiller, Lewis Benjamin

    1995-01-01

    This thesis describes techniques for the design of parallel programs that solve well-structured problems with inherent symmetry. Part I demonstrates the reduction of such problems to generalized matrix multiplication by a group-equivariant matrix. Fast techniques for this multiplication are described, including factorization, orbit decomposition, and Fourier transforms over finite groups. Our algorithms entail interaction between two symmetry groups: one arising at the software level from the problem's symmetry and the other arising at the hardware level from the processors' communication network. Part II illustrates the applicability of our symmetry -exploitation techniques by presenting a series of case studies of the design and implementation of parallel programs. First, a parallel program that solves chess endgames by factorization of an associated dihedral group-equivariant matrix is described. This code runs faster than previous serial programs, and discovered it a number of results. Second, parallel algorithms for Fourier transforms for finite groups are developed, and preliminary parallel implementations for group transforms of dihedral and of symmetric groups are described. Applications in learning, vision, pattern recognition, and statistics are proposed. Third, parallel implementations solving several computational science problems are described, including the direct n-body problem, convolutions arising from molecular biology, and some communication primitives such as broadcast and reduce. Some of our implementations ran orders of magnitude faster than previous techniques, and were used in the investigation of various physical phenomena.

  13. Two questions about surrogacy and exploitation.

    Science.gov (United States)

    Wertheimer, Alan

    1992-01-01

    In this article I will consider two related questions about surrogacy and exploitation: (1) Is surrogacy exploitative? (2) If surrogacy is exploitative, what is the moral force of this exploitation? Briefly stated, I shall argue that whether surrogacy is exploitative depends on whether exploitation must be harmful to the exploited party or whether (as I think) there can be mutually advantageous exploitation. It also depends on some facts about surrogacy about which we have little reliable evidence and on our philosophical view on what counts as a harm to the surrogate. Our answer to the second question will turn in part on the account of exploitation we invoke in answering the first question and in part on the way in which we resolve some other questions about the justification of state interference. I shall suggest, however, that if surrogacy is a form of voluntary and mutually advantageous exploitation, then there is a strong presumption that surrogacy contracts should be permitted and even enforceable, although that presumption may be overridden on other grounds.

  14. Radiation environmental impact assessment of copper exploitation

    International Nuclear Information System (INIS)

    Fan Guang; Wen Zhijian

    2010-01-01

    The radiation environmental impact of mineral exploitation on the surrounding environment has become a public concern. This paper presents the radiation environmental impact assessment of copper exploitation. Based on the project description and detailed investigations of surrounding environment, systematic radiation environmental impacts have been identified. The environmental impacts are assessed during both construction and operation phase. The environmental protection measures have also been proposed. The related conclusion and measures can play an active role in copper exploitation and environmental protection. (authors)

  15. Exploitation and exploration dynamics in recessionary times

    OpenAIRE

    Walrave, B.

    2012-01-01

    Firm performance largely depends on the ability to adapt to, and exploit, changes in the business environment. That is, firms should maintain ecological fitness by reconfiguring their resource base to cope with emerging threats and explore new opportunities, while at the same time exploiting existing resources. As such, firms possessing the ability to simultaneously perform exploitative and explorative initiatives are more resilient. In this respect, the performance implications of balancing ...

  16. Comparison between standard culture and peptide nucleic acid 16S rRNA hybridization quantification to study the influence of physico-chemical parameters on Legionella pneumophila survival in drinking water biofilms.

    Science.gov (United States)

    Gião, M S; Wilks, S A; Azevedo, N F; Vieira, M J; Keevil, C W

    2009-01-01

    Legionella pneumophila is a waterborne pathogen that is mainly transmitted by the inhalation of contaminated aerosols. In this article, the influence of several physico-chemical parameters relating to the supply of potable water was studied using a L. pneumophila peptide nucleic acid (PNA) specific probe to quantify total L. pneumophila in addition to standard culture methods. A two-stage chemostat was used to form the heterotrophic biofilms, with biofilm generating vessels fed with naturally occurring L. pneumophila. The substratum was the commonly used potable water pipe material, uPVC. It proved impossible to recover cultivable L. pneumophila due to overgrowth by other microorganisms and/or the loss of cultivability of this pathogen. Nevertheless, results obtained for total L. pneumophila cells in biofilms using a specific PNA probe showed that for the two temperatures studied (15 and 20 degrees C), there were no significant differences when shear stress was increased. However, when a source of carbon was added there was a significant increase in numbers at 20 degrees C. A comparison of the two temperatures showed that at 15 degrees C, the total cell numbers for L. pneumophila were generally higher compared with the total microbial flora, suggesting that lower temperatures support the inclusion of L. pneumophila in drinking water biofilms. The work reported in this article suggests that standard culture methods are not accurate for the evaluation of water quality in terms of L. pneumophila. This raises public health concerns since culture methods are still considered to be the gold standard for assessing the presence of this opportunistic pathogen in water.

  17. Legionella pneumophila: From potable water to treated greywater; quantification and removal during treatment.

    Science.gov (United States)

    Blanky, Marina; Rodríguez-Martínez, Sara; Halpern, Malka; Friedler, Eran

    2015-11-15

    Greywater is an alternative water source that can help alleviate stress on depleted water resources. The main options for greywater reuse are toilet flushing and garden irrigation, both producing aerosols. For that reason transmission of inhalable pathogens like Legionella present a potential risk. To improve the understanding about Legionella in greywater, we traced the pathogen seasonally from the potable water system to the final steps of the greywater treatment in four houses in northern Israel. Physicochemical and microbiological parameters were analyzed in order to assess background greywater quality and to establish possible associations with Legionella. The mean concentrations of Legionella pneumophila isolated from the potable water system were 6.4×10(2) and 5.9×10(3) cfu/l in cold and hot water respectively. By amending the ISO protocol for Legionella isolation from drinking water, we succeeded in quantifying Legionella in greywater. The mean Legionella concentrations that were found in raw, treated and treated chlorinated greywater were 1.2×10(5), 2.4×10(4) and 5.7×10(3) cfu/l respectively. While Legionella counts in potable water presented a seasonal pattern with high concentrations in summer, its counts in greywater presented an almost inversed pattern. Greywater treatment resulted in 95% decrease in Legionella counts. No significant difference was found between Legionella concentrations in potable water and the treated chlorinated greywater. These findings indicate that regarding Legionella, reusing treated chlorinated greywater would exhibit a risk that is very similar to the risk associated with using potable water for the same non-potable uses. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. The membrane protein LasM Promotes the Culturability of Legionella pneumophila in Water

    Directory of Open Access Journals (Sweden)

    Laam Li

    2016-09-01

    Full Text Available The water-borne pathogen Legionella pneumophila (Lp strongly expresses the lpg1659 gene in water. This gene encodes a hypothetical protein predicted to be a membrane protein using in silico analysis. While no conserved domains were identified in Lpg1659, similar proteins are found in many Legionella species and other aquatic bacteria. RT-qPCR showed that lpg1659 is positively regulated by the alternative sigma factor RpoS, which is essential for Lp to survive in water. These observations suggest an important role of this novel protein in the survival of Lp in water. Deletion of lpg1659 did not affect cell morphology, membrane integrity or tolerance to high temperature. Moreover, lpg1659 was dispensable for growth of Lp in rich medium, and during infection of the amoeba Acanthamoeba castellanii and of THP-1 human macrophages. However, deletion of lpg1659 resulted in an early loss of culturability in water, while over-expression of this gene promoted the culturability of Lp. Therefore, these results suggest that lpg1659 is required for Lp to maintain culturability, and possibly long-term survival, in water. Since the loss of culturability observed in the absence of Lpg1659 was complemented by the addition of trace metals into water, this membrane protein is likely a transporter for acquiring essential trace metal for maintaining culturability in water and potentially in other metal-deprived conditions. Given its role in the survival of Lp in water, Lpg1659 was named LasM for Legionella aquatic survival membrane protein.

  19. Structural and Functional Studies of Fatty Acyl Adenylate Ligases from E. coli and L. pneumophila

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z.; Swaminathan, S.; Zhou, R.; Sauder, J. M.; Tonge, P. J.; Burley, S. K.

    2011-02-18

    Fatty acyl-AMP ligase (FAAL) is a new member of a family of adenylate-forming enzymes that were recently discovered in Mycobacterium tuberculosis. They are similar in sequence to fatty acyl-coenzyme A (CoA) ligases (FACLs). However, while FACLs perform a two-step catalytic reaction, AMP ligation followed by CoA ligation using ATP and CoA as cofactors, FAALs produce only the acyl adenylate and are unable to perform the second step. We report X-ray crystal structures of full-length FAAL from Escherichia coli (EcFAAL) and FAAL from Legionella pneumophila (LpFAAL) bound to acyl adenylate, determined at resolution limits of 3.0 and 1.85 {angstrom}, respectively. The structures share a larger N-terminal domain and a smaller C-terminal domain, which together resemble the previously determined structures of FAAL and FACL proteins. Our two structures occur in quite different conformations. EcFAAL adopts the adenylate-forming conformation typical of FACLs, whereas LpFAAL exhibits a unique intermediate conformation. Both EcFAAL and LpFAAL have insertion motifs that distinguish them from the FACLs. Structures of EcFAAL and LpFAAL reveal detailed interactions between this insertion motif and the interdomain hinge region and with the C-terminal domain. We suggest that the insertion motifs support sufficient interdomain motions to allow substrate binding and product release during acyl adenylate formation, but they preclude CoA binding, thereby preventing CoA ligation.

  20. Survival and multiplication of Legionella pneumophila in municipal drinking water systems.

    Science.gov (United States)

    States, S J; Conley, L F; Kuchta, J M; Oleck, B M; Lipovich, M J; Wolford, R S; Wadowsky, R M; McNamara, A M; Sykora, J L; Keleti, G

    1987-05-01

    Studies were conducted to investigate the survival and multiplication of Legionella spp. in public drinking water supplies. An attempt was made, over a period of several years, to isolate legionellae from a municipal system. Sampling sites included the river water supply, treatment plant, finished water reservoir system, mains, and distribution taps. Despite the use of several isolation techniques, Legionella spp. could not be detected in any of the samples other than those collected from the river. It was hypothesized that this was due to the maintenance of a chlorine residual throughout the system. To investigate the potential for Legionella growth, additional water samples, collected from throughout the system, were dechlorinated, pasteurized, and inoculated with Legionella pneumophila. Subsequent growth indicated that many of these samples, especially those collected from areas affected by an accumulation of algal materials, exhibited a much greater ability to support Legionella multiplication than did river water prior to treatment. Chemical analyses were also performed on these samples. Correlation of chemical data and experimental growth results indicated that the chemical environment significantly affects the ability of the water to support multiplication, with turbidity, organic carbon, and certain metals being of particular importance. These studies indicate that the potential exists for Legionella growth within municipal systems and support the hypothesis that public water supplies may contaminate the plumbing systems of hospitals and other large buildings. The results also suggest that useful methods to control this contamination include adequate treatment plant filtration, maintenance of a chlorine residual throughout the treatment and distribution network, and effective covering of open reservoirs.

  1. The TolC protein of Legionella pneumophila plays a major role in multi-drug resistance and the early steps of host invasion.

    Directory of Open Access Journals (Sweden)

    Mourad Ferhat

    Full Text Available Pneumonia associated with Iegionnaires's disease is initiated in humans after inhalation of contaminated aerosols. In the environment, Legionella pneumophila is thought to survive and multiply as an intracellular parasite within free-living amoeba. In the genome of L. pneumophila Lens, we identified a unique gene, tolC, encoding a protein that is highly homologous to the outer membrane protein TolC of Escherichia coli. Deletion of tolC by allelic exchange in L. pneumophila caused increased sensitivity to various drugs. The complementation of the tolC mutation in trans restored drug resistance, indicating that TolC is involved in multi-drug efflux machinery. In addition, deletion of tolC caused a significant attenuation of virulence towards both amoebae and macrophages. Thus, the TolC protein appears to play a crucial role in virulence which could be mediated by its involvement in efflux pump mechanisms. These findings will be helpful in unraveling the pathogenic mechanisms of L. pneumophila as well as in developing new therapeutic agents affecting the efflux of toxic compounds.

  2. Genomic investigation of a suspected outbreak of legionella pneumophila st82 reveals undetected heterogeneity by the present gold-standard methods, denmark, july to november 2014

    DEFF Research Database (Denmark)

    Schjørring, Susanne; Stegger, M.; Kjelsø, C.

    2017-01-01

    Between July and November 2014, 15 communityacquired cases of Legionnaires’ disease (LD), including four with Legionella pneumophila serogroup 1 sequence type (ST) 82, were diagnosed in Northern Zealand, Denmark. An outbreak was suspected. No ST82 isolates were found in environmental samples and ...

  3. Distribution of sequence-based types of legionella pneumophila serogroup 1 strains isolated from cooling towers, hot springs, and potable water systems in China.

    Science.gov (United States)

    Qin, Tian; Zhou, Haijian; Ren, Hongyu; Guan, Hong; Li, Machao; Zhu, Bingqing; Shao, Zhujun

    2014-04-01

    Legionella pneumophila serogroup 1 causes Legionnaires' disease. Water systems contaminated with Legionella are the implicated sources of Legionnaires' disease. This study analyzed L. pneumophila serogroup 1 strains in China using sequence-based typing. Strains were isolated from cooling towers (n = 96), hot springs (n = 42), and potable water systems (n = 26). Isolates from cooling towers, hot springs, and potable water systems were divided into 25 sequence types (STs; index of discrimination [IOD], 0.711), 19 STs (IOD, 0.934), and 3 STs (IOD, 0.151), respectively. The genetic variation among the potable water isolates was lower than that among cooling tower and hot spring isolates. ST1 was the predominant type, accounting for 49.4% of analyzed strains (n = 81), followed by ST154. With the exception of two strains, all potable water isolates (92.3%) belonged to ST1. In contrast, 53.1% (51/96) and only 14.3% (6/42) of cooling tower and hot spring, respectively, isolates belonged to ST1. There were differences in the distributions of clone groups among the water sources. The comparisons among L. pneumophila strains isolated in China, Japan, and South Korea revealed that similar clones (ST1 complex and ST154 complex) exist in these countries. In conclusion, in China, STs had several unique allelic profiles, and ST1 was the most prevalent sequence type of environmental L. pneumophila serogroup 1 isolates, similar to its prevalence in Japan and South Korea.

  4. Simultaneous detection of Legionella species and Legionella pneumophila by duplex PCR (dPCR assay in cooling tower water samples from Jakarta, Indonesia

    Directory of Open Access Journals (Sweden)

    Andi Yasmon

    2010-11-01

    Full Text Available Aim: Since culture method is time-consuming and has low  sensitivity, we developed a duplex PCR (dPCR assay for the detection of Legionella sp. and L. pneumophila in cooling tower samples. We used culture method as a gold standard.Methods: Optimization of dPCR method was performed to obtain an assay with high sensitivity and specifi city. The optimized method was used to detect Legionella sp. dan L. pneumophila in 9 samples obtained from 9 buildings in Jakarta. For culture method, the bacteria were grown or isolated on selective growth factor supplemented-buffered charcoal yeast extract (BCYE media.Results: Of 9 samples tested by dPCR assay, 6 were positive for Legionella species,1 was positive for L. pneumophila, and 2 showed negative results. For the same samples, no Legionella sp. was detected by the culture method.Conclusion: dPCR assay was much more sensitive than the culture method and was potentially used as a rapid, specifi c and sensitive test for routine detection of Legionella sp. dan for L. pneumophila in water samples. (Med J Indones 2010; 19:223-7Keywords: BCYE media, mip gene, 16S-rRNA gene

  5. Gentamicin-Containing Peptone-Yeast Extract Medium for Cocultivation of Hartmannella vermiformis ATCC 50256 and Virulent Strains of Legionella pneumophila.

    Science.gov (United States)

    Wadowsky, R M; Wang, L; Laus, S; Dowling, J N; Kuchta, J M; States, S J; Yee, R B

    1995-12-01

    We evaluated the use of peptone-yeast extract (PY) medium, different strains of Hartmannella vermiformis, and gentamicin in a coculture system to improve the discrimination of virulent and avirulent strains of Legionella pneumophila. H. vermiformis ATCC 50256 was unique among four strains of H. vermiformis, in that it multiplied equally well in Medium 1034 and PY medium (Medium 1034 without fetal calf serum, folic acid, hemin, and yeast nucleic acid and with a 50% reduction of peptone). However, both a virulent strain of L. pneumophila and its avirulent derivative strain multiplied in cocultures when PY medium was used. The multiplication of this avirulent strain was greatly reduced by incorporating gentamicin (1 (mu)g/ml) into the cocultivation system. Five virulent-avirulent sets of L. pneumophila strains were then tested for multiplication in cocultures with H. vermiformis ATCC 50256 and the gentamicin-containing PY medium. Only the virulent strains multiplied. The modified cocultivation system can discriminate between virulent and avirulent strains of L. pneumophila.

  6. Close genetic relationship between Legionella pneumophila serogroup 1 isolates from sputum specimens and puddles on roads, as determined by sequence-based typing.

    Science.gov (United States)

    Kanatani, Jun-ichi; Isobe, Junko; Kimata, Keiko; Shima, Tomoko; Shimizu, Miwako; Kura, Fumiaki; Sata, Tetsutaro; Watahiki, Masanori

    2013-07-01

    We investigated the prevalence of Legionella species isolated from puddles on asphalt roads. In addition, we carried out sequence-based typing (SBT) analysis on the genetic relationship between L. pneumophila serogroup 1 (SG 1) isolates from puddles and from stock strains previously obtained from sputum specimens and public baths. Sixty-nine water samples were collected from puddles on roads at 6 fixed locations. Legionella species were detected in 33 samples (47.8%) regardless of season. Among the 325 isolates from puddles, strains of L. pneumophila SG 1, a major causative agent of Legionnaires' disease, were the most frequently isolated (n = 62, 19.1%). Sixty-two isolates of L. pneumophila SG 1 from puddles were classified into 36 sequence types (STs) by SBT. ST120 and ST48 were identified as major STs. Environmental ST120 strains from puddles were found for the first time in this study. Among the 14 STs of the clinical isolates (n = 19), 4 STs (n = 6, 31.6%), including ST120, were also detected in isolates from puddles on roads, and the sources of infection in these cases remained unclear. The lag-1 gene, a tentative marker for clinical isolates, was prevalent in puddle isolates (61.3%). Our findings suggest that puddles on asphalt roads serve as potential reservoirs for L. pneumophila in the environment.

  7. Legionella pneumophila: the paradox of a highly sensitive opportunistic waterborne pathogen able to persist in the environment

    Directory of Open Access Journals (Sweden)

    Jean-Marc eBerjeaud

    2016-04-01

    Full Text Available Legionella pneumophila, the major causative agent of Legionnaires’ disease, is found in freshwater environments in close association with free-living amoebae and multispecies biofilms, leading to persistence, spread, biocide resistance, and elevated virulence of the bacterium. Indeed, legionellosis outbreaks are mainly due to the ability of this bacterium to colonize and persist in water facilities, despite harsh physical and chemical treatments. However, these treatments are not totally efficient and, after a lag period, L. pneumophila may be able to quickly re-colonize these systems. Several natural compounds (biosurfactants, antimicrobial peptides… with anti-Legionella properties have recently been described in the literature, highlighting their specific activities against this pathogen. In this review, we first consider this hallmark of Legionella to resist killing, in regard to its biofilm or host-associated life style. Then, we focus more accurately on natural anti-Legionella molecules described so far, which could provide new eco-friendly and alternative ways to struggle against this important pathogen in plumbing.

  8. Electrochemical Characterization of O2 Plasma Functionalized Multi-Walled Carbon Nanotube Electrode for Legionella pneumophila DNA Sensor

    Science.gov (United States)

    Park, Eun Jin; Lee, Jun-Yong; Hyup Kim, Jun; Kug Kim, Sun; Lee, Cheol Jin; Min, Nam Ki

    2010-08-01

    An electrochemical DNA sensor for Legionella pneumophila detection was constructed using O2 plasma functionalized multi-walled carbon nanotube (MWCNT) film as a working electrode (WE). The cyclic voltammetry (CV) results revealed that the electrocatalytic activity of plasma functionalized MWCNT (pf-MWCNT) significantly changed depending on O2 plasma treatment time due to some oxygen containing functional groups on the pf-MWCNT surface. Scanning electron microscope (SEM) images and X-ray photoelectron spectroscopy (XPS) spectra were also presented the changes of their surface morphologies and oxygen composition before and after plasma treatment. From a comparison study, it was found that the pf-MWCNT WEs had higher electrocatalytic activity and more capability of probe DNA immobilization: therefore, electrochemical signal changes by probe DNA immobilization and hybridization on pf-MWCNT WEs were larger than on Au WEs. The pf-MWCNT based DNA sensor was able to detect a concentration range of 10 pM-100 nM of target DNA to detect L. pneumophila.

  9. Protein expression, crystallization and preliminary X-ray crystallographic studies of LidA from Legionella pneumophila

    International Nuclear Information System (INIS)

    Zhu, Wenzhuang; Meng, Geng; Liu, Yong; Zhang, Feiyun; Zheng, Xiaofeng

    2011-01-01

    The crystallization of recombinant lidA, a translocated substrate of the Legionella pneumophila Dot/Icm type IV secretion system, is reported. Crystals were obtained and diffracted to 2.75 Å in space group P2 1 2 1 2 1 . LidA, a translocated substrate of the Legionella pneumophila Dot/Icm type IV secretion system, is associated with maintenance of bacterial integrity and interferes with the early secretory pathway. However, the precise mechanism of LidA in these processes remains elusive. To further investigate the structure and function of LidA, the full-length protein was successfully expressed in Escherichia coli and purified. LidA was crystallized using sitting-drop vapour diffusion and diffracted to a resolution of 2.75 Å. The crystal belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 57.5, b = 64.5, c = 167.3 Å, α = β = γ = 90°. There is one molecule per asymmetric unit

  10. Comparison of pulsed corona plasma and pulsed electric fields for the decontamination of water containing Legionella pneumophila as model organism.

    Science.gov (United States)

    Banaschik, Robert; Burchhardt, Gerhard; Zocher, Katja; Hammerschmidt, Sven; Kolb, Juergen F; Weltmann, Klaus-Dieter

    2016-12-01

    Pulsed corona plasma and pulsed electric fields were assessed for their capacity to kill Legionella pneumophila in water. Electrical parameters such as in particular dissipated energy were equal for both treatments. This was accomplished by changing the polarity of the applied high voltage pulses in a coaxial electrode geometry resulting in the generation of corona plasma or an electric field. For corona plasma, generated by high voltage pulses with peak voltages of +80kV, Legionella were completely killed, corresponding to a log-reduction of 5.4 (CFU/ml) after a treatment time of 12.5min. For the application of pulsed electric fields from peak voltages of -80kV a survival of log 2.54 (CFU/ml) was still detectable after this treatment time. Scanning electron microscopy images of L. pneumophila showed rupture of cells after plasma treatment. In contrast, the morphology of bacteria seems to be intact after application of pulsed electric fields. The more efficient killing for the same energy input observed for pulsed corona plasma is likely due to induced chemical processes and the generation of reactive species as indicated by the evolution of hydrogen peroxide. This suggests that the higher efficacy and efficiency of pulsed corona plasma is primarily associated with the combined effect of the applied electric fields and the promoted reaction chemistry. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Impact of Chlorine and Heat on the Survival of Hartmannella vermiformis and Subsequent Growth of Legionella pneumophila.

    Science.gov (United States)

    Kuchta, J M; Navratil, J S; Shepherd, M E; Wadowsky, R M; Dowling, J N; States, S J; Yee, R B

    1993-12-01

    Hartmannella vermiformis, a common amoebal inhabitant of potable-water systems, supports intracellular multiplication of Legionella pneumophila and is probably important in the transportation and amplification of legionellae within these systems. To provide a practical guide for decontamination of potable-water systems, we assessed the chlorine and heat resistance of H. vermiformis. H. vermiformis cysts and trophozoites were treated independently with chlorine at concentrations of 2.0 to 10.0 ppm for 30 min and then cocultured with L. pneumophila. Both cysts and trophozoites were sensitive to concentrations between 2.0 and 4.0 ppm and above (trophozoites somewhat more so than cysts), and 10.0 ppm was lethal to both forms. Hartmannellae treated with chlorine up to a concentration of 4.0 ppm supported the growth of legionellae. To determine whether heat would be an effective addendum to chlorine treatment of amoebae, hartmannellae were subjected to temperatures of 55 and 60 degrees C for 30 min and alternatively to 50 degrees C followed by treatment with chlorine at a concentration of 2 ppm. Fewer than 0.05% of the amoebae survived treatment at 55 degrees C, and there were no survivors at 60 degrees C. Pretreatment at 50 degrees C appeared to make hartmannella cysts more susceptible to chlorine but did not further reduce the concentration of trophozoites.

  12. The economics of exploiting gas hydrates

    International Nuclear Information System (INIS)

    Döpke, Lena-Katharina; Requate, Till

    2014-01-01

    We investigate the optimal exploitation of methane hydrates, a recent discovery of methane resources under the sea floor, mainly located along the continental margins. Combustion of methane (releasing CO2) and leakage through blow-outs (releasing CH4) contribute to the accumulation of greenhouse gases. A second externality arises since removing solid gas hydrates from the sea bottom destabilizes continental margins and thus increases the risk of marine earthquakes. We show that in such a model three regimes can occur: i) resource exploitation will be stopped in finite time, and some of the resource will stay in situ, ii) the resource will be used up completely in finite time, and iii) the resource will be exhausted in infinite time. We also show how to internalize the externalities by policy instruments. - Highlights: • We set up a model of optimal has hydrate exploitation • We incorporate to types of damages: contribution to global warming and geo-hazards • We characterize optimal exploitation paths and study decentralization with an exploitation tax. • Three regimes can occur: • i) exploitation in finite time and some of the stock remaining in situ, • ii) exploitation in finite time and the resource will be exhausted, • iii) exploitation and exhaustion in infinite time

  13. Exploitation and exploration dynamics in recessionary times

    NARCIS (Netherlands)

    Walrave, B.

    2012-01-01

    Firm performance largely depends on the ability to adapt to, and exploit, changes in the business environment. That is, firms should maintain ecological fitness by reconfiguring their resource base to cope with emerging threats and explore new opportunities, while at the same time exploiting

  14. Packaging of Sin Goods - Commitment or Exploitation?

    DEFF Research Database (Denmark)

    Nafziger, Julia

    to such self-control problems, and possibly exploit them, by offering different package sizes. In a competitive market, either one or three (small, medium and large) packages are offered. In contrast to common intuition, the large, and not the small package is a commitment device. The latter serves to exploit...

  15. SEXUAL EXPLOITATION AND ABUSE BY UN PEACEKEEPERS ...

    African Journals Online (AJOL)

    Allaiac

    sexual exploitation of children by peacekeepers is particularly insidious. ... sexual exploitation and abuse should involve an understanding of the social .... The charges of sexual misconduct, and the consequent media exposure, have ..... awareness programmes such as video tapes, lectures and training manuals, designed.

  16. Exploration, Exploitation, and Organizational Coordination Mechanisms

    Directory of Open Access Journals (Sweden)

    Silvio Popadiuk

    2016-03-01

    Full Text Available This paper presents an empirical relationship among exploration, exploitation, and organizational coordination mechanisms, classified as the centralization of decision-making, formalization, and connectedness. In order to analyze the findings of this survey, we used two techniques: Principal Component Analysis (PCA and Partial Least Squares Path Modeling (PLS-PM. Our analysis was supported by 249 answers from managers of companies located in Brazil (convenience sampling. Contrary to expectations, centralization and exploitation were negatively associated. Our data supports the research hypothesis that formalization is positively associated with exploitation. Although the relationship between formalization and exploration were significant, the result is contrary to the research hypothesis that we made. The relationships among connectedness and exploitation, and connectedness and exploration were both positive and significant. This relationship means that the more connectedness increases, the higher the likelihood of exploitation and exploration.

  17. Molecular Typing of Legionella pneumophila Isolates in the Province of Quebec from 2005 to 2015.

    Directory of Open Access Journals (Sweden)

    Simon Lévesque

    Full Text Available Legionella is found in natural and man-made aquatic environments, such as cooling towers and hot water plumbing infrastructures. Legionella pneumophila serogroup 1 (Lp1 is the most common etiological agent causing waterborne disease in the United States and Canada. This study reports the molecular characterization of Lp strains during a 10 year period. We conducted sequence-based typing (SBT analysis on a large set of Lp isolates (n = 284 to investigate the province of Quebec sequence types (STs distribution in order to identify dominant clusters. From 2005 to 2015, 181 clinical Lp isolates were typed by SBT (141 sporadic cases and 40 outbreak related cases. From the same period of time, 103 environmental isolates were also typed. Amongst the 108 sporadic cases of Lp1 typed, ST-62 was the most frequent (16.6%, followed by ST-213 (10.2%, ST-1 (8.3% and ST-37 (8.3%. Amongst other serogroups (SG, ST-1327 (SG5 (27.3% and ST-378 (SG10 (12.2% were the most frequent. From the environmental isolates, ST-1 represent the more frequent SBT type (26.5%. Unweighted pair group method with arithmetic mean (UPGMA dendrogram from the 108 sporadic cases of SG1 contains 4 major clusters (A to D of related STs. Cluster B contains the majority of the strains (n = 61 and the three most frequent STs in our database (ST-62, ST-213 and ST-1. During the study period, we observed an important increase in the incidence rate in Quebec. All the community associated outbreaks, potentially or confirmed to be associated with a cooling tower were caused by Lp1 strains, by opposition to hospital associated outbreaks that were caused by serogroups of Lp other than SG1. The recent major Quebec City outbreak caused by ST-62, and the fact that this genotype is the most common in the province supports whole genome sequencing characterization of this particular sequence type in order to understand its evolution and associated virulence factors.

  18. Herbivory eliminates fitness costs of mutualism exploiters.

    Science.gov (United States)

    Simonsen, Anna K; Stinchcombe, John R

    2014-04-01

    A common empirical observation in mutualistic interactions is the persistence of variation in partner quality and, in particular, the persistence of exploitative phenotypes. For mutualisms between hosts and symbionts, most mutualism theory assumes that exploiters always impose fitness costs on their host. We exposed legume hosts to mutualistic (nitrogen-fixing) and exploitative (non-nitrogen-fixing) symbiotic rhizobia in field conditions, and manipulated the presence or absence of insect herbivory to determine if the costly fitness effects of exploitative rhizobia are context-dependent. Exploitative rhizobia predictably reduced host fitness when herbivores were excluded. However, insects caused greater damage on hosts associating with mutualistic rhizobia, as a consequence of feeding preferences related to leaf nitrogen content, resulting in the elimination of fitness costs imposed on hosts by exploitative rhizobia. Our experiment shows that herbivory is potentially an important factor in influencing the evolutionary dynamic between legumes and rhizobia. Partner choice and host sanctioning are theoretically predicted to stabilize mutualisms by reducing the frequency of exploitative symbionts. We argue that herbivore pressure may actually weaken selection on choice and sanction mechanisms, thus providing one explanation of why host-based discrimination mechanisms may not be completely effective in eliminating nonbeneficial partners. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  19. Designation of the European Working Group on Legionella Infection (EWGLI) amplified fragment length polymorphism types of Legionella pneumophila serogroup 1 and results of intercentre proficiency testing Using a standard protocol

    DEFF Research Database (Denmark)

    Fry, N K; Bangsborg, Jette Marie; Bergmans, A

    2002-01-01

    The utility of amplified fragment length polymorphism (AFLP) analysis as a genotyping method for the epidemiological typing of Legionella pneumophila serogroup 1 has been previously demonstrated. This study (i). reports recommendations for the designation of the European Working Group on Legionella...... centres), and 92% (7 centres) to 100% (7 centres). The AFLP method as described is robust and rapid and allows the genotypic comparison of isolates of Legionella pneumophila between different testing centres without the need for exchange of the strains studied....

  20. Neumonía por Legionella pneumophila: Experiencia en un Hospital Universitario de Buenos Aires Neumonia due to Legionella pneumophila. Experience gathered in a University Hospital in Buenos Aires

    Directory of Open Access Journals (Sweden)

    Carlos M. Luna

    2004-04-01

    Full Text Available La enfermedad de los legionarios es una causa de neumonía adquirida en la comunidad (NAC reconocida en todo el mundo. En Latinoamérica su incidencia es desconocida. En este estudio se analizó a 9 pacientes con NAC por Legionella pneumophila atendidos entre 1997 y 2001 en el Hospital de Clínicas José de San Martín de la Universidad de Buenos Aires. Se registraron datos de antecedentes, enfermedad actual, contactos, exposición laboral, examen físico, pruebas de laboratorio y uso previo de antibióticos, y se tomó en cuenta la presencia de criterios de gravedad. Nueve pacientes presentaron diagnóstico de NAC por Legionella, ninguno refirió antecedentes de viajes recientes; cuatro de ellos debieron ser internados en unidades de cuidado intensivo. Siete pacientes tenían antecedentes de tabaquismo, 4 tenían EPOC y un paciente linfoma no-Hodgkin. Nuestra casuística corrobora la baja especificidad de la clínica y estudios complementarios para predecir esta etiología. El aislamiento de Legionella es dificultoso, la seroconversión permite el diagnóstico retrospectivo y requiere plazos prolongados y el antígeno urinario aporta un diagnóstico inmediato. Cuando la legionelosis aparece en casos aislados, como ocurriría en Argentina, si no se piensa en esta etiología no se llegará al diagnóstico. Legionella pneumophila es un patógeno de NAC en nuestro medio, debe buscarse mejor, particularmente en pacientes graves, inmunodeprimidos y en fumadores con enfermedad pulmonar obstructiva crónica (EPOC.Legionnaires’ disease is a well recognized cause of community acquired pneumonia (CAP all around the world. In Latin America its incidence remains unknown. This study analyzed a cohort of 9 patients with CAP due to Legionella pneumophila observed from 1997 to 2001, in the Hospital de Clínicas José de San Martín, University of Buenos Aires. Clinical history included recent illnesses, work exposure, physical exam, prior antibiotic use and

  1. Peat exploitation - Environment. Effects and measures

    International Nuclear Information System (INIS)

    Stenbeck, G.

    1996-01-01

    This report gives a detailed description of the influence of peat exploitation on the land-, water- and atmospheric environments. Proposals for mitigatory measures to minimize damage to the environment are also given

  2. SEXUAL EXPLOITATION AND ABUSE BY UN PEACEKEEPERS ...

    African Journals Online (AJOL)

    Allaiac

    from sexual exploitation and sexual abuse (ST/SGB/2003/13) (UN, Secretary .... In addition, in most situations, UN personnel have enjoyed immunity from local .... 9 Official UN statistics show a higher incidence of allegations reported against.

  3. Exploitation of linkage learning in evolutionary algorithms

    CERN Document Server

    Chen, Ying-ping

    2010-01-01

    The exploitation of linkage learning is enhancing the performance of evolutionary algorithms. This monograph examines recent progress in linkage learning, with a series of focused technical chapters that cover developments and trends in the field.

  4. Exploitative and Deceptive Resource Acquisition Strategies

    Directory of Open Access Journals (Sweden)

    Joshua J. Reynolds

    2015-07-01

    Full Text Available Life history strategy (LHS and life history contingencies (LHCs should theoretically influence the use of exploitative and deceptive resource acquisition strategies. However, little research has been done in this area. The purpose of the present work was to create measures of exploitative strategies and test the predictions of life history theory. Pilot studies developed and validated a behavioral measure of cheating called the Dot Game. The role of individual LHS and LHCs (manipulated via validated story primes on cheating was investigated in Study 1. Studies 2a through 2c were conducted to develop and validate a self-report measure called the Exploitative and Deceptive Resource Acquisition Strategy Scale (EDRASS. Finally, Study 3 investigated life history and EDRASS. Results indicated that while LHS influences exploitative strategies, life history contingences had little effect. Implications of these findings are discussed.

  5. Organ sales: exploitative at any price?

    Science.gov (United States)

    Lawlor, Rob

    2014-05-01

    In many cases, claims that a transaction is exploitative will focus on the details of the transaction, such as the price paid or conditions. For example, in a claim that a worker is exploited, the grounds for the claim are usually that the pay is not sufficient or the working conditions too dangerous. In some cases, however, the claim that a transaction is exploitative is not seen to rely on these finer details. Many, for example, claim that organ sales would be exploitative, in a way that doesn't seem to depend on the details. This article considers, but ultimately rejects, a number of arguments which could be used to defend this sort of claim. © 2012 John Wiley & Sons Ltd.

  6. A Theory of Exploitative Child Labor

    OpenAIRE

    Carol Ann Rogers; Kenneth A. Swinnerton

    2003-01-01

    Child labor laws should aim to protect children who work, instead of trying to remove children from work. In this paper, we identify an instance when the risk of exploitation lowers the expected bene…t of child labor to the child,and therefore suppresses child labor force participation. Targeted legal intervention that lowers or removes the risk of exploitation raises child participation in the labor market, child welfare, and overall societal welfare. Targeting on child labor more broadly ma...

  7. Managing the Innovators for Exploration and Exploitation

    Directory of Open Access Journals (Sweden)

    C. Annique UN

    2007-09-01

    Full Text Available I analyze how to manage employees to achieve a balance between exploration and exploitation in large established firms. Previous studies suggest that, although firms need to undertake both exploration and exploitation simultaneously, this is difficult either because of the scarcity of resources or because of the incompatibility of these two processes. Proposed solutions have been ambidexterity, punctuated equilibrium or specialization. I suggest another method: managing employees. Specifically, I argue that using the so-called “innovative” system of human resource management practices, consisting of team-based incentive system, team-based job design, and job rotation, enables the firm to undertake exploration and exploitation simultaneously because it provides the psychological safety for people to explore new knowledge to make novel products and develops employees to have the perspective-taking capability that enables the integration of knowledge cross-functionally for efficiency. Using the so-called “traditional” system of human resource management practices, consisting of individual-based incentive system, individual-based job design, and no job rotation, has limited impact on either exploration or exploitation because it does not create the psychological safety for people to explore new knowledge and does not develop the perspective-taking capability needed for exploitation. Moreover, mixing practices from both systems is better than only using the traditional system in achieving exploration or exploitation, but less effective than only using the innovative system as the mix of practices can create inconsistent expectations on employees.

  8. UV-A photocatalytic treatment of Legionella pneumophila bacteria contaminated airflows through three-dimensional solid foam structured photocatalytic reactors

    Energy Technology Data Exchange (ETDEWEB)

    Josset, Sebastien; Hajiesmaili, Shabnam; Begin, Dominique; Edouard, David; Pham-Huu, Cuong [Laboratoire des Materiaux, Surfaces et Procedes pour la Catalyse (LMSPC), European Laboratory for Catalysis and Surface Sciences (ELCASS), CNRS, Strasbourg University, 25 rue Becquerel 67087 Strasbourg (France); Lett, Marie-Claire [Laboratoire de Genetique Moleculaire, Genomique, Microbiologie, CNRS, Strasbourg University, 28, rue Goethe 67083 Strasbourg Cedex (France); Keller, Nicolas, E-mail: nkeller@chimie.u-strasbg.fr [Laboratoire des Materiaux, Surfaces et Procedes pour la Catalyse (LMSPC), European Laboratory for Catalysis and Surface Sciences (ELCASS), CNRS, Strasbourg University, 25 rue Becquerel 67087 Strasbourg (France); Keller, Valerie [Laboratoire des Materiaux, Surfaces et Procedes pour la Catalyse (LMSPC), European Laboratory for Catalysis and Surface Sciences (ELCASS), CNRS, Strasbourg University, 25 rue Becquerel 67087 Strasbourg (France)

    2010-03-15

    A 3D-structured photocatalytic media was designed for allowing a tubular reactor to work in a traversing-flow mode at low pressure drops with a strong increase in the surface area-to-volume ratio inside the reactor. A protective polysiloxane coating was performed for protecting a structured polyurethane foam and anchoring the active TiO{sub 2} particles. Filled with the 3D-structured solid foam supporting TiO{sub 2} photocatalyst, the reactor could thus take advantages from the static mixer effect and from the low pressure drop resulting from the reticulated foam support. Very efficient decontamination levels towards airborne Legionella pneumophila bacteria were reached in a single-pass test mode.

  9. The presence of opportunistic pathogens, Legionella spp., L. pneumophila and Mycobacterium avium complex, in South Australian reuse water distribution pipelines.

    Science.gov (United States)

    Whiley, H; Keegan, A; Fallowfield, H; Bentham, R

    2015-06-01

    Water reuse has become increasingly important for sustainable water management. Currently, its application is primarily constrained by the potential health risks. Presently there is limited knowledge regarding the presence and fate of opportunistic pathogens along reuse water distribution pipelines. In this study opportunistic human pathogens Legionella spp., L. pneumophila and Mycobacterium avium complex were detected using real-time polymerase chain reaction along two South Australian reuse water distribution pipelines at maximum concentrations of 10⁵, 10³ and 10⁵ copies/mL, respectively. During the summer period of sampling the concentration of all three organisms significantly increased (P < 0.05) along the pipeline, suggesting multiplication and hence viability. No seasonality in the decrease in chlorine residual along the pipelines was observed. This suggests that the combination of reduced chlorine residual and increased water temperature promoted the presence of these opportunistic pathogens.

  10. The Legionella pneumophila IcmSW complex interacts with multiple Dot/Icm effectors to facilitate type IV translocation.

    Directory of Open Access Journals (Sweden)

    Eric D Cambronne

    2007-12-01

    Full Text Available Many gram-negative pathogens use a type IV secretion system (T4SS to deliver effector proteins into eukaryotic host cells. The fidelity of protein translocation depends on the efficient recognition of effector proteins by the T4SS. Legionella pneumophila delivers a large number of effector proteins into eukaryotic cells using the Dot/Icm T4SS. How the Dot/Icm system is able to recognize and control the delivery of effectors is poorly understood. Recent studies suggest that the IcmS and IcmW proteins interact to form a stable complex that facilitates translocation of effector proteins by the Dot/Icm system by an unknown mechanism. Here we demonstrate that the IcmSW complex is necessary for the productive translocation of multiple Dot/Icm effector proteins. Effector proteins that were able to bind IcmSW in vitro required icmS and icmW for efficient translocation into eukaryotic cells during L. pneumophila infection. We identified regions in the effector protein SidG involved in icmSW-dependent translocation. Although the full-length SidG protein was translocated by an icmSW-dependent mechanism, deletion of amino terminal regions in the SidG protein resulted in icmSW-independent translocation, indicating that the IcmSW complex is not contributing directly to recognition of effector proteins by the Dot/Icm system. Biochemical and genetic studies showed that the IcmSW complex interacts with a central region of the SidG protein. The IcmSW interaction resulted in a conformational change in the SidG protein as determined by differences in protease sensitivity in vitro. These data suggest that IcmSW binding to effectors could enhance effector protein delivery by mediating a conformational change that facilitates T4SS recognition of a translocation domain located in the carboxyl region of the effector protein.

  11. Studio del comportamento di Acanthamoeba. polyphaga in presenza di Legionella pneumophila e di altri batteri ad habitat acquatico

    Directory of Open Access Journals (Sweden)

    M. Bondi

    2003-05-01

    Full Text Available Le amebe a vita libera sono state oggetto di diversi studi negli ultimi anni, non solo per le loro potenzialità patogene nei confronti dell’uomo, ma anche per l’importante ruolo che svolgono in natura, dove agiscono come predatori in grado di controllare le popolazioni batteriche. Alcuni degli organismi fagocitati però possono evitare la lisi fagosomiale e mantenere la loro condizione vitale a livello intracellulare, divenendo endosimbionti. Le amebe fungono così da riserva per questi batteri, proteggendoli da difficili condizioni extracellulari e provvedendo ad un ambiente consono alla loro replicazione. Tale tipo di interazione è particolarmente studiata in Legionella pneumophila, dal momento che l’ampia diffusione di questo germe, nonché la sua virulenza, pare siano fortemente influenzate dalla capacità di parassitare protozoi appartenenti ai generi Acanthamoeba, Naegleria e Balamuthia. Al fine di ottenere maggiori informazioni sui fattori favorenti o inibenti lo sviluppo di questi protozoi, è stato studiato il comportamento di un ceppo di Acanthamoeba polyphaga coltivato, in solido e in liquido, in associazione con L. pneumophila ed altri batteri ad habitat acquatico (Pseudomonas, Aeromonas, Achromobacter, Burkholderia. Su tappeti di cellule batteriche allestiti in Non Nutrient Agar (NNA, A.polyphaga si è mostrata in grado di moltiplicarsi utilizzando come nutrimento tutti i ceppi testati, nonostante alcuni, come Burkholderia cepacia SSV6 e Achromobacter xylox SS28, risultino più idonei al suo sviluppo. In piastre a pozzetti addizionate di acqua condottata autoclavata, il protozoo ha mostrato una buona capacità di sopravvivenza, non risultando inoltre influenzato dalla presenza di legionella o dei batteri acquatici testati. Dal momento che, fra i batteri descritti come capaci di vita intra-amebica, sono inclusi patogeni quali Chlamydia, Legionella, Listeria e Rickettsiae, risulta necessario riconsiderare la rilevanza clinica

  12. Exploitation of Labour and Exploitation of Commodities: a “New Interpretation”

    OpenAIRE

    Veneziani, Roberto; Yoshihara, Naoki

    2011-01-01

    In the standard Okishio-Morishima approach, the existence of profits is proved to be equivalent to the exploitation of labour. Yet, it can also be proved that the existence of profits is equivalent to the ‘exploitation’ of any good. Labour and commodity exploitation are just different numerical representations of the productiveness of the economy. This paper presents an alternative approach to exploitation theory which is related to the New Interpretation (Duménil 1980; Foley 1982). In this a...

  13. Exploitation in International Paid Surrogacy Arrangements

    Science.gov (United States)

    Wilkinson, Stephen

    2015-01-01

    Abstract Many critics have suggested that international paid surrogacy is exploitative. Taking such concerns as its starting point, this article asks: (1) how defensible is the claim that international paid surrogacy is exploitative and what could be done to make it less exploitative? (2) In the light of the answer to (1), how strong is the case for prohibiting it? Exploitation could in principle be dealt with by improving surrogates' pay and conditions. However, doing so may exacerbate problems with consent. Foremost amongst these is the argument that surrogates from economically disadvantaged countries cannot validly consent because their background circumstances are coercive. Several versions of this argument are examined and I conclude that at least one has some merit. The article's overall conclusion is that while ethically there is something to be concerned about, paid surrogacy is in no worse a position than many other exploitative commercial transactions which take place against a backdrop of global inequality and constrained options, such as poorly‐paid and dangerous construction work. Hence, there is little reason to single surrogacy out for special condemnation. On a policy level, the case for prohibiting international commercial surrogacy is weak, despite legitimate concerns about consent and background poverty. PMID:27471338

  14. Exploitation in International Paid Surrogacy Arrangements.

    Science.gov (United States)

    Wilkinson, Stephen

    2016-05-01

    Many critics have suggested that international paid surrogacy is exploitative. Taking such concerns as its starting point, this article asks: (1) how defensible is the claim that international paid surrogacy is exploitative and what could be done to make it less exploitative? (2) In the light of the answer to (1), how strong is the case for prohibiting it? Exploitation could in principle be dealt with by improving surrogates' pay and conditions. However, doing so may exacerbate problems with consent. Foremost amongst these is the argument that surrogates from economically disadvantaged countries cannot validly consent because their background circumstances are coercive. Several versions of this argument are examined and I conclude that at least one has some merit. The article's overall conclusion is that while ethically there is something to be concerned about, paid surrogacy is in no worse a position than many other exploitative commercial transactions which take place against a backdrop of global inequality and constrained options, such as poorly-paid and dangerous construction work. Hence, there is little reason to single surrogacy out for special condemnation. On a policy level, the case for prohibiting international commercial surrogacy is weak, despite legitimate concerns about consent and background poverty.

  15. Identification of Variable-Number Tandem-Repeat (VNTR) Sequences in Legionella pneumophila and Development of an Optimized Multiple-Locus VNTR Analysis Typing Scheme▿

    Science.gov (United States)

    Pourcel, Christine; Visca, Paolo; Afshar, Baharak; D'Arezzo, Silvia; Vergnaud, Gilles; Fry, Norman K.

    2007-01-01

    The utility of a genotypic typing assay for Legionella pneumophila was investigated. A multiple-locus variable number of tandem repeats (VNTR) analysis (MLVA) scheme using PCR and agarose gel electrophoresis is proposed based on eight minisatellite markers. Panels of well-characterized strains were examined in a multicenter analysis to validate the assay and to compare its performance to that of other genotyping assays. Excellent typeability, reproducibility, stability, and epidemiological concordance were observed. The MLVA type or profile is composed of a string of allele numbers, corresponding to the number of repeats at each VNTR locus, separated by commas, in a predetermined order. A database containing information from 99 L. pneumophila serogroup 1 strains and four strains of other serogroups and their MLVA profiles, which can be queried online, is available from http://bacterial-genotyping.igmors.u-psud.fr/. PMID:17251393

  16. The use of heteroduplex analysis of polymerase chain reaction products to support the possible transmission of Legionella pneumophila from a malfunctioning automobile air conditioner.

    Science.gov (United States)

    Pinar, Ahmet; Ramirez, Julio A; Schindler, Laura L; Miller, Richard D; Summersgill, James T

    2002-03-01

    Air conditioner condensates have not been previously associated with cases of Legionnaires' disease. We report the possible transmission of Legionella pneumophila serogroup 1 from a malfunctioning automobile air conditioning system's leaking water onto the floorboard of a car driven for a long distance by the patient. Heteroduplex analysis of polymerase chain reaction products was used to help establish an epidemiologic link between the water specimen and the patient.

  17. Three Antagonistic Cyclic di-GMP-Catabolizing Enzymes Promote Differential Dot/Icm Effector Delivery and Intracellular Survival at the Early Steps of Legionella pneumophila Infection

    Science.gov (United States)

    Allombert, Julie; Lazzaroni, Jean-Claude; Baïlo, Nathalie; Gilbert, Christophe; Charpentier, Xavier; Doublet, Patricia

    2014-01-01

    Legionella pneumophila is an intracellular pathogen which replicates within protozoan cells and can accidently infect alveolar macrophages, causing an acute pneumonia in humans. The second messenger cyclic di-GMP (c-di-GMP) has been shown to play key roles in the regulation of various bacterial processes, including virulence. While investigating the function of the 22 potential c-di-GMP-metabolizing enzymes of the L. pneumophila Lens strain, we found three that directly contribute to its ability to infect both protozoan and mammalian cells. These three enzymes display diguanylate cyclase (Lpl0780), phosphodiesterase (Lpl1118), and bifunctional diguanylate cyclase/phosphodiesterase (Lpl0922) activities, which are all required for the survival and intracellular replication of L. pneumophila. Mutants with deletions of the corresponding genes are efficiently taken up by phagocytic cells but are partially defective for the escape of the Legionella-containing vacuole (LCV) from the host degradative endocytic pathway and result in lower survival. In addition, Lpl1118 is required for efficient endoplasmic reticulum recruitment to the LCV. Trafficking and biogenesis of the LCV are dependent upon the orchestrated actions of several type 4 secretion system Dot/Icm effectors proteins, which exhibit differentially altered translocation in the three mutants. While translocation of some effectors remained unchanged, others appeared over- and undertranslocated. A general translocation offset of the large repertoire of Dot/Icm effectors may be responsible for the observed defects in the trafficking and biogenesis of the LCV. Our results suggest that L. pneumophila uses cyclic di-GMP signaling to fine-tune effector delivery and ensure effective evasion of the host degradative pathways and establishment of a replicative vacuole. PMID:24379287

  18. Seasonal distribution of Legionella spp. and L. pneumophila in a river in Taiwan evaluated with culture-confirmed and direct DNA extraction methods

    Science.gov (United States)

    Tung, Min-Che; Chang, Tien-Yu; Hsu, Bing-Mu; Shen, Shu-Min; Huang, Jen-Te; Kao, Po-Min; Chiu, Yi-Chou; Fan, Cheng-Wei; Huang, Yu-Li

    2013-07-01

    In this study, we evaluated the presence and amount of Legionella in along a river in Taiwan, and the relations between seasonal distribution of Legionella spp. and geographic characteristics in the watershed were also evaluated. Water samples were pre-treated and analyzed with culture-confirmed and direct DNA extraction methods. For culture-confirmed method, water samples were cultivated through a series of selective media, and candidate colonies were confirmed by PCR. For direct DNA extraction method, direct DNA extraction was performed from pre-treated water samples. The DNA extracts were analyzed with PCR and DNA sequence analysis for species determination, quantitative PCR (qPCR) was performed to quantify Legionella concentration in the water sample. In all, 150 water samples were included in this study, with 73 (48.6%) water samples detected with Legionella spp., and 17 with L. pneumophila. Over 80% Legionella spp. detections were through direct DNA extraction method, but more than 80% L. pneumophila detections were through culture-confirmed method. While detection of Legionella spp. was done with two methods, positive results were found through only one method. Legionella spp. was detected in all seasons with detection rate ranging between 34.3-58.8% and seasonal average concentration from 1.9 × 102 to 7.1 × 103 CFU/L. Most of the L. pneumophila detections were from samples collected in fall (38.2%) and summer (6.0%), which also coincided with increased cases of Legionellosis reported through Center of Disease Control in Taiwan. The high prevalence and concentration of Legionella spp. and L. pneumophila in the surface waters should be further evaluated for potential health risks.

  19. Detection of cell-associated or soluble antigens of Legionella pneumophila serogroups 1 to 6, Legionella bozemanii, Legionella dumoffii, Legionella gormanii, and Legionella micdadei by staphylococcal coagglutination tests.

    OpenAIRE

    Wilkinson, H W; Fikes, B J

    1981-01-01

    Current methods used for the detection of whole-cell isolates of Legionella or for the detection of Legionella soluble antigens are technically impractical for many clinical laboratories. The purpose of this study was to explore practical alternatives. The results showed that whole cell isolates of Legionella pneumophila serogroups 1 to 6, Legionella bozemanii, Legionella dumoffii, Legionella gormanii, and Legionella micdadei were identified specifically by a simple slide agglutination test o...

  20. Oil exploitation and the environmental Kuznets curve

    International Nuclear Information System (INIS)

    Esmaeili, Abdoulkarim; Abdollahzadeh, Negar

    2009-01-01

    This study refers to a panel estimation of an environmental Kuznets curve (EKC) for oil to determine the factors most affecting oil exploitation in 38 oil-producing countries during 1990-2000. Control variables such as oil reserves, oil price, population, political rights, and the Gini index were used to determine its contribution to the main EKC model. The empirical results fully support the existence of an EKC for oil exploitation. Furthermore, the result indicates that the proved oil reserves has a significant and positive role in oil production, but oil price and population do not significantly affect crude oil production. Also, increased freedoms and a better income distribution will reduce the rate of oil exploitation. Thus, policies aiming at enhancing democratic society and better income distribution would be more compatible with sustainability. (author)

  1. Oil exploitation and the environmental Kuznets curve

    Energy Technology Data Exchange (ETDEWEB)

    Esmaeili, Abdoulkarim; Abdollahzadeh, Negar [Department of Agricultural Economics, College of Agriculture, Shiraz University, Shiraz, Fars (Iran)

    2009-01-15

    This study refers to a panel estimation of an environmental Kuznets curve (EKC) for oil to determine the factors most affecting oil exploitation in 38 oil-producing countries during 1990-2000. Control variables such as oil reserves, oil price, population, political rights, and the Gini index were used to determine its contribution to the main EKC model. The empirical results fully support the existence of an EKC for oil exploitation. Furthermore, the result indicates that the proved oil reserves has a significant and positive role in oil production, but oil price and population do not significantly affect crude oil production. Also, increased freedoms and a better income distribution will reduce the rate of oil exploitation. Thus, policies aiming at enhancing democratic society and better income distribution would be more compatible with sustainability. (author)

  2. Rethinking exploitation: a process-centered account.

    Science.gov (United States)

    Jansen, Lynn A; Wall, Steven

    2013-12-01

    Exploitation has become an important topic in recent discussions of biomedical and research ethics. This is due in no small measure to the influence of Alan Wertheimer's path-breaking work on the subject. This paper presents some objections to Wertheimer's account of the concept. The objections attempt to show that his account places too much emphasis on outcome-based considerations and too little on process-based considerations. Building on these objections, the paper develops an alternative process-centered account of the concept. This alternative account of exploitation takes as its point of departure the broadly Kantian notion that it is wrong to use another as an instrument for the advancement of one's own ends. It sharpens this slippery notion and adds a number of refinements to it. The paper concludes by arguing that process-centered accounts of exploitation better illuminate the ethical challenges posed by research on human subjects than outcome-centered accounts.

  3. Shale gas exploitation: Status, problems and prospect

    Directory of Open Access Journals (Sweden)

    Shiqian Wang

    2018-02-01

    Full Text Available Over the past five years, great progress has been made in shale gas exploitation, which has become the most driving force for global gas output growth. Hydrocarbon extraction from shale helps drive the USA on the road to energy independence. Besides, shale oil & gas production has been kept in a sustained growth by continuous improvement in drilling efficiency and well productivity in the case of tumbling oil prices and rig counts. Shale gas reserves and production have been in a rapid growth in China owing to the Lower Paleozoic Wufeng and Longmaxi shale gas exploitation in the Sichuan Basin, which has become an important sector for the future increment of gas reserves and output in China. However, substantial progress has been made neither in non-marine shale gas exploitation as previously expected nor in the broad complicated tectonic areas in South China for which a considerable investment was made. Analysis of the basic situation and issues in domestic shale gas development shows that shale gas exploitation prospects are constrained by many problems in terms of resources endowment, horizontal well fracturing technology, etc. especially in non-marine shale deposits and complicated tectonic areas in South China where hot shales are widely distributed but geological structures are found severely deformed and over matured. Discussion on the prospects shows that the sustained and steady growth in shale gas reserves and production capacity in the coming years lies in the discovery and supersession of new shale plays in addition to Wufeng and Longmaxi shale plays, and that a technological breakthrough in ultra-high-pressure and ultra-deep (over 3500 m buried in the Sichuan Basin marine shale gas exploitation is the key and hope. Keywords: Shale gas, Exploitation, Marine facies, Hot shale, Resource endowment, Sichuan Basin, South China, Complicated tectonic area, Gas play

  4. The htpAB operon of Legionella pneumophila cannot be deleted in the presence of the groE chaperonin operon of Escherichia coli.

    Science.gov (United States)

    Nasrallah, Gheyath K; Gagnon, Elizabeth; Orton, Dennis J; Garduño, Rafael A

    2011-11-01

    HtpB, the chaperonin of the intracellular bacterial pathogen Legionella pneumophila , displays several virulence-related functions in vitro. To confirm HtpB's role in vivo, host infections with an htpB deletion mutant would be required. However, we previously reported that the htpAB operon (encoding co-chaperonin and chaperonin) is essential. We attempted here to delete htpAB in a L. pneumophila strain carrying the groE operon (encoding the Escherichia coli co-chaperonin and chaperonin). The groE operon was inserted into the chromosome of L. pneumophila Lp02, and then allelic replacement of htpAB with a gentamicin resistance cassette was attempted. Although numerous potential postallelic replacement transformants showed a correct selection phenotype, we still detected htpAB by PCR and full-size HtpB by immunoblot. Southern blot and PCR analysis indicated that the gentamicin resistance cassette had apparently integrated in a duplicated htpAB region. However, we showed by Southern blot that strain Lp02, and the Lp02 derivative carrying the groE operon, have only one copy of htpAB. These results confirmed that the htpAB operon cannot be deleted, not even in the presence of the groE operon, and suggested that attempts to delete htpAB under strong phenotypic selection result in aberrant genetic recombinations that could involve duplication of the htpAB locus.

  5. Research on Legionella pneumophila in hospital supply networks - DOI: 10.3395/reciis.v1i2.85en

    Directory of Open Access Journals (Sweden)

    Aldo Pacheco Ferreira

    2007-12-01

    Full Text Available The species of Legionella (gram-negative aerobic bacillus are widely distributed in water environments. The Legionellaceae family comprises a group of fastidious bacteria that requires special isolation techniques, and of which the Legionella pneumophila is the member which is most commonly identified as the cause of human diseases or of the worsening of health conditions. The purpose of this work is to verify conditions in randomly chosen hospitals from the public system for the development of Legionella pneumophila, and, thus, contribute to the debate on legislation and technical standardization in the network, with the purpose of controlling and preventing the presence of this bacillus in the Brazilian hospital system. At the same time, some physicochemical and colimetric parameters (total and thermo-tolerant coliforms were evaluated aiming at defining the total quality of water used. The results show the presence of coliforms and Legionella sp in the water used in the monitored hospitals. In this way, it is shown that the maintenance of the quality of water used in hospitals is fundamental, as well as the carrying out of biological tests for the detection of Legionella pneumophila so that the necessary safety of the hospital environment can be achieved.

  6. On the dynamics of exploited fish populations

    National Research Council Canada - National Science Library

    Beverton, R. J. H; Holt, Sidney J

    1993-01-01

    ...-brooding cichlids, and viviparity in many sharks and toothcarps. Moreover, fish are of considerable importance to the survival of the human species in the form of nutritious, delicious and diverse food. Rational exploitation and management of our global stocks of fishes must rely upon a detailed and precise insight of their biology. The...

  7. Child Exploitation: Some Pieces of the Puzzle.

    Science.gov (United States)

    Rohlader, Dorothy

    The report addresses the status in North Carolina and in the nation of child exploitation. Legislative and judicial backgrounds of child pornography and child prostitution are reviewed, and difficulties in obtaining statistical data are noted. Law enforcement issues in pornography are cited, and suggestions for further legislation regarding child…

  8. Exploiting a natural auxotrophy for genetic selection.

    Science.gov (United States)

    Ramage, Elizabeth; Gallagher, Larry; Manoil, Colin

    2012-08-01

    We exploited the natural histidine auxotrophy of Francisella species to develop hisD (encodes histidinol dehydrogenase) as a positive selection marker. A shuttle plasmid (pBR103) carrying Escherichia coli hisD and designed for cloning of PCR fragments replicated in both attenuated and highly virulent Francisella strains. During this work, we formulated a simplified defined growth medium for Francisella novicida.

  9. Growth, Mortality and Exploitation Rates of Sarotherodon ...

    African Journals Online (AJOL)

    Evans

    ABSTRACT. Sarotherodon melanotheron population of Dominli Lagoon in the Western Region of Ghana was studied for its growth and mortality parameters as well as exploitation rate. The study generally aimed at providing basic information necessary for the assessment and management of the fish stock in the lagoon.

  10. Economic factors of vulnerability trade and exploitation

    NARCIS (Netherlands)

    Allodi, L.

    2017-01-01

    Cybercrime markets support the development and diffusion of new attack technologies, vulnerability exploits, and malware. Whereas the revenue streams of cyber attackers have been studied multiple times in the literature, no quantitative account currently exists on the economics of attack acquisition

  11. Exploiting indigenous knowledge in the environmental conservation ...

    African Journals Online (AJOL)

    ... of agriculture and reared livestock (especially goats). Over several years, they developed sustainable and effective exploitation mechanisms of the existing biodiversity resources to satisfy their individual needs and those of their societies in general. Journal of Language, Technology and Entrepreneurship in Africa Vol.

  12. Exploiting citation contexts for physics retrieval

    DEFF Research Database (Denmark)

    Dabrowska, Anna; Larsen, Birger

    2015-01-01

    The text surrounding citations within scientific papers may contain terms that usefully describe cited documents and can benefit retrieval. We present a preliminary study that investigates appending ci- tation contexts from citing documents to cited documents in the iSearch test collection. We ex...... in a large collection of physics papers, paving the way for future research that exploits citation contexts for retrieval....

  13. Dissemination and Exploitation: Project Goals beyond Science

    Science.gov (United States)

    Hamann, Kristin; Reitz, Anja

    2017-04-01

    Dissemination and Exploitation are essential parts of public funded projects. In Horizon 2020 a plan for the exploitation and dissemination of results (PEDR) is a requirement. The plan should contain a clear vision on the objectives of the project in relation to actions for dissemination and potential exploitation of the project results. The actions follow the basic idea to spread the knowledge and results gathered within the project and face the challenge of how to bring the results into potentially relevant policy circle and how they impact the market. The plan follows the purpose to assess the impact of the project and to address various target groups who are interested in the project results. Simply put, dissemination concentrates on the transfer of knowledge and exploitation on the commercialization of the project. Beyond the question of the measurability of project`s impact, strategies within science marketing can serve purposes beyond internal and external communication. Accordingly, project managers are facing the challenge to implement a dissemination and exploitation strategy that ideally supports the identification of all partners with the project and matches the current discourse of the project`s content within the society, politics and economy. A consolidated plan might unite all projects partners under a central idea and supports the identification with the project beyond the individual research questions. Which applications, strategies and methods can be used to bring forward a PEDR that accompanies a project successfully and allows a comprehensive assessment of the project afterwards? Which hurdles might project managers experience in the dissemination process and which tasks should be fulfilled by the project manager?

  14. Trolling may intensify exploitation in crappie fisheries

    Science.gov (United States)

    Meals, K. O.; Dunn, A. W.; Miranda, Leandro E.

    2012-01-01

    In some parts of the USA, anglers targeting crappies Pomoxis spp. are transitioning from mostly stationary angling with a single pole around submerged structures to using multiple poles while drifting with the wind or under power. This shift in fishing methods could result in a change in catch efficiency, possibly increasing exploitation rates to levels that would be of concern to managers. We studied the catch statistics of anglers fishing while trolling with multiple poles (trollers) and those fishing with single poles (polers) in Mississippi reservoirs. Specifically, we tested whether (1) various catch statistics differed between trollers and polers, (2) catch rates of trollers were related to the number of poles fished, and (3) trollers could raise exploitation rates to potentially unsustainable levels. Results showed that participation in the crappie fisheries was about equally split between polers and trollers. In spring, 90% of crappie anglers were polers; in summer, 85% of crappie anglers were trollers. The size of harvested crappies was similar for the two angler groups, but the catch per hour was almost three times higher for trollers than for polers. Catch rates by trollers were directly correlated to the number of poles fished, although the relationship flattened as the number of poles increased. The average harvest rate for one troller fishing with three poles was similar to the harvest rate obtained by one poler. Simulations predicted that at the existing mix of about 50% polers and 50% trollers and with no restrictions on the number of poles used by trollers, exploitation of crappies is about 1.3 times higher than that in a polers-only fishery; under a scenario in which 100% of crappie anglers were trollers, exploitation was forecasted to increase to about 1.7 times the polers-only rate. The efficiency of trolling for crappies should be of concern to fishery managers because crappie fisheries are mostly consumptive and may increase exploitation

  15. Brote epidémico de neumonías por Legionella pneumophila en niños cubanos

    Directory of Open Access Journals (Sweden)

    Roberto Razón Behar

    2002-09-01

    Full Text Available La Legionella pneumophila es uno de los patógenos responsable de neumonías atípicas, a través de la inhalación de aerosoles o aspiración de líquidos infectados. Se detectó un brote epidémico de neumonías por Legionella, originado por la aspiración de agua contaminada de una piscina en un grupo de niños cubanos. El agente causal se identificó en 5 de 9 pacientes, por la técnica de inmunofluorescencia indirecta en muestras de sueros pareados. Los síntomas y signos más frecuentes fueron malestar general, anorexia, astenia, fiebre persistente de 39 °C a 40 °C (103 °F a 105 °F, mialgias, cefaleas, náuseas, vómitos, dolor abdominal, diarreas, tos húmeda, dolor torácico y polipnea. Durante el desarrollo de la enfermedad, el tratamiento antibiótico fue empírico (incluyendo los macrólidos, por no tener confirmado el diagnóstico. Todos los pacientes evolucionaron satisfactoriamente. Se reportó un brote epidémico de neumonías por Legionella en niños por primera vez en Cuba, lo cual tiene importancia clínica y epidemiológica.The legionella pneumophila is one of the pathogens responsible for atypic pneumonias by the inhalation of aerosols or aspiration of infected liquids. An epidemic outbreak of pneumonias caused by Legionella was detected among a group of Cuban children. It was originated by the aspiration of contaminated water in a swimming pool. The causal agent was identified in 5 of 9 patients by using the indirect immunofluorescence technique in samples of matched sera. The most frequent symptoms and signs were malaise, anorexia, asthenia, persistent fever from 39°C to 40°C (103° F to 105° F, myalgias, headache, nauseas, vomits, abdominal pain, diarrheas, moist cough, thoracic pain and polypnoea. The antibiotic treatment was empiric (including the macrolides during the development of the disease, since the diagnosis was not confirmed. The patients’ evolution was satisfactory. An epidemic outbreak of pneumonias

  16. Intelligence, mapping, and geospatial exploitation system (IMAGES)

    Science.gov (United States)

    Moellman, Dennis E.; Cain, Joel M.

    1998-08-01

    This paper provides further detail to one facet of the battlespace visualization concept described in last year's paper Battlespace Situation Awareness for Force XXI. It focuses on the National Imagery and Mapping Agency (NIMA) goal to 'provide customers seamless access to tailorable imagery, imagery intelligence, and geospatial information.' This paper describes Intelligence, Mapping, and Geospatial Exploitation System (IMAGES), an exploitation element capable of CONUS baseplant operations or field deployment to provide NIMA geospatial information collaboratively into a reconnaissance, surveillance, and target acquisition (RSTA) environment through the United States Imagery and Geospatial Information System (USIGS). In a baseplant CONUS setting IMAGES could be used to produce foundation data to support mission planning. In the field it could be directly associated with a tactical sensor receiver or ground station (e.g. UAV or UGV) to provide near real-time and mission specific RSTA to support mission execution. This paper provides IMAGES functional level design; describes the technologies, their interactions and interdependencies; and presents a notional operational scenario to illustrate the system flexibility. Using as a system backbone an intelligent software agent technology, called Open Agent ArchitectureTM (OAATM), IMAGES combines multimodal data entry, natural language understanding, and perceptual and evidential reasoning for system management. Configured to be DII COE compliant, it would utilize, to the extent possible, COTS applications software for data management, processing, fusion, exploitation, and reporting. It would also be modular, scaleable, and reconfigurable. This paper describes how the OAATM achieves data synchronization and enables the necessary level of information to be rapidly available to various command echelons for making informed decisions. The reasoning component will provide for the best information to be developed in the timeline

  17. Sustainable exploitation and management of aquatic resources

    DEFF Research Database (Denmark)

    Neuenfeldt, Stefan; Köster, Fritz

    2014-01-01

    DTU Aqua conducts research, provides advice,educates at university level and contributes toinnovation in sustainable exploitation andmanagement of aquatic resources. The vision of DTUAqua is to enable ecologically and economicallysustainable exploitation of aquatic resourcesapplying an integrated...... management. Marineecosystems aims at understanding the mechanisms that govern the interaction between individuals,species and populations in an ecosystem enabling us to determine the stability and flexibility of theecosystem.Marine living resources looks at the sustainable utilization of fish and shellfish...... stocks.Ecosystem effects expands from the ecosystem approach to fisheries management to an integratedapproach where other human activities are taken into consideration. Fisheries management developsmethods, models and tools for predicting and evaluating the effects of management measures andregulations...

  18. Exploiting HRM in support of lean manufacturing

    DEFF Research Database (Denmark)

    Jørgensen, Frances; Matthiesen, Rikke

    The purpose of this paper is to investigate the ways in HRM practices are-and could potentially be-exploited to support lean manufacturing in practice. First, a review of the pertinent literature regarding HRM, SHRM, and lean manufacturing is presented to provide an understanding of the mechanisms...... by which HRM practices could, theoretically, be used to support a lean implementation. Data presented in the paper are derived from 1) a longitudinal case study on lean implementation and 2) from managers currently involved with lean manufacturing in a second company. The relevant literature and the data...... depicting the potential role in supporting HRM/lean integrated practices. The analysis of the model with respect to the theoretical background emphasizes a number of areas in which HRM could be more fully exploited in order to more successfully support lean implementation, for example, by stressing HRM...

  19. Exploiting Non-Markovianity for Quantum Control.

    Science.gov (United States)

    Reich, Daniel M; Katz, Nadav; Koch, Christiane P

    2015-07-22

    Quantum technology, exploiting entanglement and the wave nature of matter, relies on the ability to accurately control quantum systems. Quantum control is often compromised by the interaction of the system with its environment since this causes loss of amplitude and phase. However, when the dynamics of the open quantum system is non-Markovian, amplitude and phase flow not only from the system into the environment but also back. Interaction with the environment is then not necessarily detrimental. We show that the back-flow of amplitude and phase can be exploited to carry out quantum control tasks that could not be realized if the system was isolated. The control is facilitated by a few strongly coupled, sufficiently isolated environmental modes. Our paradigmatic example considers a weakly anharmonic ladder with resonant amplitude control only, restricting realizable operations to SO(N). The coupling to the environment, when harnessed with optimization techniques, allows for full SU(N) controllability.

  20. Exploiting Quantum Resonance to Solve Combinatorial Problems

    Science.gov (United States)

    Zak, Michail; Fijany, Amir

    2006-01-01

    Quantum resonance would be exploited in a proposed quantum-computing approach to the solution of combinatorial optimization problems. In quantum computing in general, one takes advantage of the fact that an algorithm cannot be decoupled from the physical effects available to implement it. Prior approaches to quantum computing have involved exploitation of only a subset of known quantum physical effects, notably including parallelism and entanglement, but not including resonance. In the proposed approach, one would utilize the combinatorial properties of tensor-product decomposability of unitary evolution of many-particle quantum systems for physically simulating solutions to NP-complete problems (a class of problems that are intractable with respect to classical methods of computation). In this approach, reinforcement and selection of a desired solution would be executed by means of quantum resonance. Classes of NP-complete problems that are important in practice and could be solved by the proposed approach include planning, scheduling, search, and optimal design.

  1. Exploiting Inhibitory Siglecs to Combat Food Allergies

    Science.gov (United States)

    2017-10-01

    AWARD NUMBER: W81XWH-16-1-0302 TITLE: Exploiting Inhibitory Siglecs to Combat Food Allergies PRINCIPAL INVESTIGATOR: Michael Kulis, Ph.D...CONTRACTING ORGANIZATION: University of North Carolina at Chapel Hill Chapel Hill, NC 27599 REPORT DATES: October 2017 TYPE OF REPORT: Annual PREPARED FOR...Department of Defense, Washington Headquarters Services , Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite

  2. Dandruff: The most commercially exploited skin disease

    Directory of Open Access Journals (Sweden)

    Ranganathan S

    2010-01-01

    Full Text Available The article discuss in detail about the prevalence, pathophysiology, clinical manifestations of dandruff including the etio-pathology. The article also discusses in detail about various treatment methods available for dandruff. The status of dandruff being amphibious - a disease/disorder, and relatively less medical intervention is sought after for the treatment, dandruff is the most commercially exploited skin and scalp disorder/disease by personal care industries.

  3. Exploiting partial knowledge for efficient model analysis

    OpenAIRE

    Macedo, Nuno; Cunha, Alcino; Pessoa, Eduardo José Dias

    2017-01-01

    The advancement of constraint solvers and model checkers has enabled the effective analysis of high-level formal specification languages. However, these typically handle a specification in an opaque manner, amalgamating all its constraints in a single monolithic verification task, which often proves to be a performance bottleneck. This paper addresses this issue by proposing a solving strategy that exploits user-provided partial knowledge, namely by assigning symbolic bounds to the problem’s ...

  4. Amplifiers Exploiting Thermal Noise Canceling: A Review

    OpenAIRE

    Klumperink, Eric A.M.; Bruccoleri, Federico; Stroet, Peter; Nauta, Bram

    2004-01-01

    Wide-band LNAs suffer from a fundamental trade-off between noise figure NF and source impedance matching, which limits NF to values typically above 3dB. Recently, a feed-forward noise canceling technique has been proposed to break this trade-off. This paper reviews the principle of the technique and its key properties. Although the technique has been applied to wideband CMOS LNAs, it can just as well be implemented exploiting transconductance elements realized with oth...

  5. Exploiting thesauri knowledge in medical guideline formalization

    OpenAIRE

    Serban, R.C.; ten Teije, A.C.M.

    2009-01-01

    Objectives: As in software product lifecycle, the effort spent in maintaining medical knowl edge in guidelines can be reduced, if modularization, formalization and tracking of domain knowledge are employed across the guideline development phases. Methods: We propose to exploit and combine knowledge templates with medical background knowledge from existing thesauri in order to produce reusable building blocks used in guideline development. These tem- plates enable easier guideline formalizatio...

  6. Exploitation as the Unequal Exchange of Labour : An Axiomatic Approach

    OpenAIRE

    Yoshihara, Naoki; Veneziani, Roberto

    2009-01-01

    In subsistence economies with general convex technology and rational optimising agents, a new, axiomatic approach is developed, which allows an explicit analysis of the core positive and normative intuitions behind the concept of exploitation. Three main new axioms, called Labour Exploitation in Subsistence Economies , Relational Exploitation , and Feasibility of Non-Exploitation , are presented and it is proved that they uniquely characterise a definition of exploitation conceptually related...

  7. Security option file - Exploitation (DOS-Expl)

    International Nuclear Information System (INIS)

    2016-01-01

    This document aims at presenting functions performed by Cigeo during its exploitation phase, its main technical and security options which are envisaged with respect to different types of internal or external risks, and a first assessment of its impact on mankind and on the environment during its exploitation in normal operation as well as in incidental or accidental situations. A first volume addresses security principles, approach and management in relationship with the legal and regulatory framework. The second volume presents input data related to waste parcels and used for the installation sizing and operation, the main site characteristics, the main technical options regarding structures and equipment, and the main options regarding exploitation (parcel management, organisational and human aspects, and effluent management). The third volume describes how parcel are processed from their arrival to their setting in storage compartment, an inventory of internal and external risks, and a first assessment of consequences of scenarios on mankind and on the environment. The fourth volume presents options and operations which are envisaged regarding Cigeo closure, and inventory of associated risks

  8. Effect of temperature and colonization of Legionella pneumophila and Vermamoeba vermiformis on bacterial community composition of copper drinking water biofilms.

    Science.gov (United States)

    Buse, Helen Y; Ji, Pan; Gomez-Alvarez, Vicente; Pruden, Amy; Edwards, Marc A; Ashbolt, Nicholas J

    2017-07-01

    It is unclear how the water-based pathogen, Legionella pneumophila (Lp), and associated free-living amoeba (FLA) hosts change or are changed by the microbial composition of drinking water (DW) biofilm communities. Thus, this study characterized the bacterial community structure over a 7-month period within mature (> 600-day-old) copper DW biofilms in reactors simulating premise plumbing and assessed the impact of temperature and introduction of Lp and its FLA host, Vermamoeba vermiformis (Vv), co-cultures (LpVv). Sequence and quantitative PCR (qPCR) analyses indicated a correlation between LpVv introduction and increases in Legionella spp. levels at room temperature (RT), while at 37°C, Lp became the dominant Legionella spp. qPCR analysis suggested Vv presence may not be directly associated with Lp biofilm growth at RT and 37°C, but may contribute to or be associated with non-Lp legionellae persistence at RT. Two-way PERMANOVA and PCoA revealed that temperature was a major driver of microbiome diversity. Biofilm community composition also changed over the seven-month period and could be associated with significant shifts in dissolved oxygen, alkalinity and various metals in the influent DW. Hence, temperature, biofilm age, DW quality and transient intrusions/amplification of pathogens and FLA hosts may significantly impact biofilm microbiomes and modulate pathogen levels over extended periods. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  9. Short-Term and Long-Term Survival and Virulence of Legionella pneumophila in the Defined Freshwater Medium Fraquil.

    Directory of Open Access Journals (Sweden)

    Nilmini Mendis

    Full Text Available Legionella pneumophila (Lp is the etiological agent responsible for Legionnaires' disease, a potentially fatal pulmonary infection. Lp lives and multiplies inside protozoa in a variety of natural and man-made water systems prior to human infection. Fraquil, a defined freshwater medium, was used as a highly reproducible medium to study the behaviour of Lp in water. Adopting a reductionist approach, Fraquil was used to study the impact of temperature, pH and trace metal levels on the survival and subsequent intracellular multiplication of Lp in Acanthamoeba castellanii, a freshwater protozoan and a natural host of Legionella. We show that temperature has a significant impact on the short- and long-term survival of Lp, but that the bacterium retains intracellular multiplication potential for over six months in Fraquil. Moreover, incubation in Fraquil at pH 4.0 resulted in a rapid decline in colony forming units, but was not detrimental to intracellular multiplication. In contrast, variations in trace metal concentrations had no impact on either survival or intracellular multiplication in amoeba. Our data show that Lp is a resilient bacterium in the water environment, remaining infectious to host cells after six months under the nutrient-deprived conditions of Fraquil.

  10. Influence of Sampling Season and Sampling Protocol on Detection of Legionella Pneumophila Contamination in Hot Water / Paraugu Ņemšanas Sezonalitātes Un Paraugu Ņemšanas Metodes Ietekme Uz Legionella Pneumophila Kontaminācijas Noteikšanu Karstajš Ūdenī

    Directory of Open Access Journals (Sweden)

    Pūle Daina

    2016-08-01

    Full Text Available Legionella pneumophila is an environmental pathogen of engineered water systems that can cause different forms of legionellosis - from mild fever to potentially lethal pneumonia. Low concentrations of legionellae in natural habitats can increase markedly in engineered hot water systems where water temperatures are below 55 °C. In the current study, we aimed to investigate the influence of sampling season, hot water temperature and sampling protocol on occurrence of L. pneumophila. A total of 120 hot water samples from 20 apartment buildings were collected in two sampling periods - winter 2014 (n = 60 and summer 2015 (n = 60. Significantly higher occurrence of L. pneumophila was observed in summer 2015. Significant differences in temperature for negative and positive samples were not observed, which can be explained by low water temperatures at the point of water consumption. Temperature above 55 °C was observed only once, for all other sampling events it ranged from 14 °C to 53 °C.

  11. Cloud Based Earth Observation Data Exploitation Platforms

    Science.gov (United States)

    Romeo, A.; Pinto, S.; Loekken, S.; Marin, A.

    2017-12-01

    In the last few years data produced daily by several private and public Earth Observation (EO) satellites reached the order of tens of Terabytes, representing for scientists and commercial application developers both a big opportunity for their exploitation and a challenge for their management. New IT technologies, such as Big Data and cloud computing, enable the creation of web-accessible data exploitation platforms, which offer to scientists and application developers the means to access and use EO data in a quick and cost effective way. RHEA Group is particularly active in this sector, supporting the European Space Agency (ESA) in the Exploitation Platforms (EP) initiative, developing technology to build multi cloud platforms for the processing and analysis of Earth Observation data, and collaborating with larger European initiatives such as the European Plate Observing System (EPOS) and the European Open Science Cloud (EOSC). An EP is a virtual workspace, providing a user community with access to (i) large volume of data, (ii) algorithm development and integration environment, (iii) processing software and services (e.g. toolboxes, visualization routines), (iv) computing resources, (v) collaboration tools (e.g. forums, wiki, etc.). When an EP is dedicated to a specific Theme, it becomes a Thematic Exploitation Platform (TEP). Currently, ESA has seven TEPs in a pre-operational phase dedicated to geo-hazards monitoring and prevention, costal zones, forestry areas, hydrology, polar regions, urban areas and food security. On the technology development side, solutions like the multi cloud EO data processing platform provides the technology to integrate ICT resources and EO data from different vendors in a single platform. In particular it offers (i) Multi-cloud data discovery, (ii) Multi-cloud data management and access and (iii) Multi-cloud application deployment. This platform has been demonstrated with the EGI Federated Cloud, Innovation Platform Testbed Poland

  12. Heisenberg's heirs exploit loopholes in his law

    International Nuclear Information System (INIS)

    Taubes, G.

    1994-01-01

    This article describes research into Heisenberg's Uncertainty Principle. Loopholes in the principle have led to a series of experiments using sophisticated optical techniques to extract information from a quantum system without disturbing the variable being measured. The experiments are based on a technique called back-action evasion, which exploits the possibility of channeling all the uncertainty generated by measuring one quantum variable (e.g. laser beam intensity) onto a related variable known as the conjugate observable (beam phase). These experiments and others are described

  13. Liposomal cancer therapy: exploiting tumor characteristics

    DEFF Research Database (Denmark)

    Kaasgaard, Thomas; Andresen, Thomas Lars

    2010-01-01

    an overview of current strategies for improving the different stages of liposomal cancer therapy, which involve transporting drug-loaded liposomes through the bloodstream, increasing tumor accumulation, and improving drug release and cancer cell uptake after accumulation at the tumor target site. What...... the reader will gain: The review focuses on strategies that exploit characteristic features of solid tumors, such as abnormal vasculature, overexpression of receptors and enzymes, as well as acidic and thiolytic characteristics of the tumor microenvironment. Take home message: It is concluded that the design...

  14. Pilot plant for exploitation of geothermal waters

    Directory of Open Access Journals (Sweden)

    Stojiljković Dragan T.

    2006-01-01

    Full Text Available In Sijarinska spa, there are some 15 mineral and thermomineral springs, that are already being used for therapeutic purposes. For the exploitation of heat energy boring B-4 is very interesting. It is a boring of a closed type, with the water temperature of about 78°C and a flow rate of about 33 l/s. Waters with the flow rate of about 6 l/s are currently used for heating of the Gejzer hotel, and waters of the flow rate of about 0,121 l/s for the pilot drying plant. The paper presents this pilot plant. .

  15. Exploiting Redundancy in an OFDM SDR Receiver

    Directory of Open Access Journals (Sweden)

    Tomas Palenik

    2009-01-01

    Full Text Available Common OFDM system contains redundancy necessary to mitigate interblock interference and allows computationally effective single-tap frequency domain equalization in receiver. Assuming the system implements an outer error correcting code and channel state information is available in the receiver, we show that it is possible to understand the cyclic prefix insertion as a weak inner ECC encoding and exploit the introduced redundancy to slightly improve error performance of such a system. In this paper, an easy way to implement modification to an existing SDR OFDM receiver is presented. This modification enables the utilization of prefix redundancy, while preserving full compatibility with existing OFDM-based communication standards.

  16. Geothermal resources: exploration and exploitation. A bibliography

    Energy Technology Data Exchange (ETDEWEB)

    1976-07-01

    This comprehensive bibliography contains 5476 citations of foreign and domestic research reports, journal articles, patents, conference proceedings, and books concerned with the exploration and exploitation of geothermal resources. The coverage dates back as far as useful references could be obtained and extends through June 1976. References are arranged in broad subject categories and are made up of complete bibliographic citations. These are followed by a listing of subject descriptors used to describe the subject content of each reference. Four indexes are included: Corporate, Personal Author, Subject, and Report Number. Also included is a list of journals from which articles were selected. (LBS)

  17. Algorithms exploiting ultrasonic sensors for subject classification

    Science.gov (United States)

    Desai, Sachi; Quoraishee, Shafik

    2009-09-01

    Proposed here is a series of techniques exploiting micro-Doppler ultrasonic sensors capable of characterizing various detected mammalian targets based on their physiological movements captured a series of robust features. Employed is a combination of unique and conventional digital signal processing techniques arranged in such a manner they become capable of classifying a series of walkers. These processes for feature extraction develops a robust feature space capable of providing discrimination of various movements generated from bipeds and quadrupeds and further subdivided into large or small. These movements can be exploited to provide specific information of a given signature dividing it in a series of subset signatures exploiting wavelets to generate start/stop times. After viewing a series spectrograms of the signature we are able to see distinct differences and utilizing kurtosis, we generate an envelope detector capable of isolating each of the corresponding step cycles generated during a walk. The walk cycle is defined as one complete sequence of walking/running from the foot pushing off the ground and concluding when returning to the ground. This time information segments the events that are readily seen in the spectrogram but obstructed in the temporal domain into individual walk sequences. This walking sequence is then subsequently translated into a three dimensional waterfall plot defining the expected energy value associated with the motion at particular instance of time and frequency. The value is capable of being repeatable for each particular class and employable to discriminate the events. Highly reliable classification is realized exploiting a classifier trained on a candidate sample space derived from the associated gyrations created by motion from actors of interest. The classifier developed herein provides a capability to classify events as an adult humans, children humans, horses, and dogs at potentially high rates based on the tested sample

  18. [Comparison and evaluation of the Binax EIA and Biotest EIA urinary antigen kits for detection of Legionella pneumophila antigen in urine samples].

    Science.gov (United States)

    Rastawicki, Waldemar; Rokosz, Natalia; Jagielski, Marek

    2011-01-01

    The Binax and the Biotest urinary antigen kits for detection of L. pneumophila antigen were compared by testing of selected 67 urine samples obtained from EWGLI as reference samples in External Quality Assessment Scheme. Thirty nine were positive with the Binax kit (100% of sensitivity), and 33 were positive with the Biotest (84.6% of sensitivity). The test specificities were 100% for the both kits. It was concluded that the Binax kit was more suitable for the routine diagnosis of Legionella infections than the Biotest kit.

  19. Synthese und Charakterisierung von potenziellen Inhibitoren des „Macrophage infectivity potentiator“ (Mip) Proteins von Legionella pneumophila - Ein neuer Ansatz in der Legionellose-Therapie

    OpenAIRE

    Juli, Christina

    2012-01-01

    Die vorliegende Arbeit beschäftigt sich mit der Synthese und Charakterisierung potenzieller Inhibitoren des Oberflächenproteins Mip von Legionella pneumophila. Der gramnegative Mikroorganismus ist der ursächliche Erreger der Legionellose. Die Erkrankung kann in zwei verschiedenen Formen auftreten, dem Pontiac-Fieber, einer Grippe-ähnlichen Atemwegserkrankung, und der Legionärskrankheit, einer schweren Lungenentzündung mit einer Mortalitätsrate von bis zu 30 %. Natürliche und künstlich geschaf...

  20. The DotA protein from Legionella pneumophila is secreted by a novel process that requires the Dot/Icm transporter

    OpenAIRE

    Nagai, Hiroki; Roy, Craig R.

    2001-01-01

    Legionella pneumophila requires the dot/icm genes to create an organelle inside eukaryotic host cells that will support bacterial replication. The dot/icm genes are predicted to encode a type IV-related secretion apparatus. However, no proteins have been identified that require the dot/icm genes for secretion. In this study we show that the DotA protein, which was previously found to be a polytopic membrane protein, is secreted by the Dot/Icm transporter into culture supernatants. Secreted Do...

  1. Competing Discourses about Youth Sexual Exploitation in Canadian News Media.

    Science.gov (United States)

    Saewyc, Elizabeth M; Miller, Bonnie B; Rivers, Robert; Matthews, Jennifer; Hilario, Carla; Hirakata, Pam

    2013-10-01

    Media holds the power to create, maintain, or break down stigmatizing attitudes, which affect policies, funding, and services. To understand how Canadian news media depicts the commercial sexual exploitation of children and youth, we examined 835 Canadian newspaper articles from 1989-2008 using a mixed methods critical discourse analysis approach, comparing representations to existing research about sexually exploited youth. Despite research evidence that equal rates of boys and girls experience exploitation, Canadian news media depicted exploited youth predominantly as heterosexual girls, and described them alternately as victims or workers in a trade, often both in the same story. News media mentioned exploiters far less often than victims, and portrayed them almost exclusively as male, most often called 'customers' or 'consumers,' and occasionally 'predators'; in contrast, research has documented the majority of sexually exploited boys report female exploiters. Few news stories over the past two decades portrayed the diversity of victims, perpetrators, and venues of exploitation reported in research. The focus on victims but not exploiters helps perpetuate stereotypes of sexual exploitation as business or a 'victimless crime,' maintains the status quo, and blurs responsibility for protecting youth under the UN Convention on the Rights of the Child. Health care providers and researchers can be advocates for accuracy in media coverage about sexual exploitation; news reporters and editors should focus on exploiters more than victims, draw on existing research evidence to avoid perpetuating stereotypes, and use accurate terms, such as commercial sexual exploitation, rather than terms related to business or trade.

  2. ROUNDTABLE - SESSION 2 EXPLOITATION, CONSERVATION AND LEGISLATION

    Directory of Open Access Journals (Sweden)

    EDSMAN L.

    2004-01-01

    Full Text Available The link between socioeconomics and conservation and the role of legislation in conservation work was discussed in the group with participants from nine European countries. Interest and knowledge among the general public, stakeholders and managers is the key to successful conservation of native crayfish species. Exploitation and conservation do not necessarily exclude each other. A controlled fishery, where it can be sustained, may be an essential tool for conservation by increasing the general awareness and involving more people in the task of protecting the native crayfish species. This strategy is mainly possible for the noble crayfish in the northern part of its distribution, where strong traditions connected to crayfish also exist. A balance between utilisation and overexploitation has to be found and local guidelines for sustainable exploitation produced. Media, the Internet and educational material aimed at schools and stakeholders are excellent ways of reaching a wide audience with information. Universal objectives, rules and regulations at the European level are desirable and the noble crayfish and the stone crayfish should be included in Annex II of the Habitat Directive. Based on this framework detailed regulations are best worked out at the national level, considering the specific crayfish situation in the country. Information about the legislation, the purpose of the legislation and the consequences when not obeying it should be distributed. Stricter regulation of the trade with live alien crayfish is vital because of the associated risk of introducing new diseases and species.

  3. Uncovering Indicators of Commercial Sexual Exploitation.

    Science.gov (United States)

    Bounds, Dawn; Delaney, Kathleen R; Julion, Wrenetha; Breitenstein, Susan

    2017-07-01

    It is estimated that annually 100,000 to 300,000 youth are at risk for sex trafficking; a commercial sex act induced by force, fraud, or coercion, or any such act where the person induced to perform such an act is younger than 18 years of age. Increasingly, such transactions are occurring online via Internet-based sites that serve the commercial sex industry. Commercial sex transactions involving trafficking are illegal; thus, Internet discussions between those involved must be veiled. Even so, transactions around sex trafficking do occur. Within these transactions are innuendos that provide one avenue for detecting potential activity. The purpose of this study is to identify linguistic indicators of potential commercial sexual exploitation within the online comments of men posted on an Internet site. Six hundred sixty-six posts from five Midwest cities and 363 unique members were analyzed via content analysis. Three main indicators were found: the presence of youth or desire for youthfulness, presence of pimps, and awareness of vulnerability. These findings begin a much-needed dialogue on uncovering online risks of commercial sexual exploitation and support the need for further research on Internet indicators of sex trafficking.

  4. Large size space construction for space exploitation

    Science.gov (United States)

    Kondyurin, Alexey

    2016-07-01

    Space exploitation is impossible without large space structures. We need to make sufficient large volume of pressurized protecting frames for crew, passengers, space processing equipment, & etc. We have to be unlimited in space. Now the size and mass of space constructions are limited by possibility of a launch vehicle. It limits our future in exploitation of space by humans and in development of space industry. Large-size space construction can be made with using of the curing technology of the fibers-filled composites and a reactionable matrix applied directly in free space. For curing the fabric impregnated with a liquid matrix (prepreg) is prepared in terrestrial conditions and shipped in a container to orbit. In due time the prepreg is unfolded by inflating. After polymerization reaction, the durable construction can be fitted out with air, apparatus and life support systems. Our experimental studies of the curing processes in the simulated free space environment showed that the curing of composite in free space is possible. The large-size space construction can be developed. A project of space station, Moon base, Mars base, mining station, interplanet space ship, telecommunication station, space observatory, space factory, antenna dish, radiation shield, solar sail is proposed and overviewed. The study was supported by Humboldt Foundation, ESA (contract 17083/03/NL/SFe), NASA program of the stratospheric balloons and RFBR grants (05-08-18277, 12-08-00970 and 14-08-96011).

  5. PROBA-V Mission Exploitation Platform

    Directory of Open Access Journals (Sweden)

    Erwin Goor

    2016-07-01

    Full Text Available As an extension of the PROBA-Vegetation (PROBA-V user segment, the European Space Agency (ESA, de Vlaamse Instelling voor Technologisch Onderzoek (VITO, and partners TRASYS and Spacebel developed an operational Mission Exploitation Platform (MEP to drastically improve the exploitation of the PROBA-V Earth Observation (EO data archive, the archive from the historical SPOT-VEGETATION mission, and derived products by researchers, service providers, and thematic users. The analysis of the time series of data (petabyte range is addressed, as well as the large scale on-demand processing of the complete archive, including near real-time data. The platform consists of a private cloud environment, a Hadoop-based processing environment and a data manager. Several applications are released to the users, e.g., a full resolution viewing service, a time series viewer, pre-defined on-demand processing chains, and virtual machines with powerful tools and access to the data. After an initial release in January 2016 a research platform was deployed gradually, allowing users to design, debug, and test applications on the platform. From the PROBA-V MEP, access to, e.g., Sentinel-2 and Sentinel-3 data will be addressed as well.

  6. zero day exploits and national readiness for cyber-warfare

    African Journals Online (AJOL)

    HOD

    A zero day vulnerability is an unknown exploit that divulges security flaws in software before such a flaw is publicly ... Keywords: exploits, zero day, vulnerability, cyberspace, cyber-warfare. 1. ..... industries and companies across the globe. The.

  7. The Theory of Exploitation as the Unequal Exchange of Labour

    OpenAIRE

    Veneziani, Roberto; Yoshihara, Naoki

    2016-01-01

    This paper analyses the normative and positive foundations of the theory of exploitation as the unequal exchange of labour (UEL). The key intuitions behind all of the main approaches to UEL exploitation are explicitly analysed as a series of formal claims in a general economic environment. It is then argued that these intuitions can be captured by one fundamental axiom - called Labour Exploitation - which defines the basic domain of all UEL exploitation forms and identifies the formal and the...

  8. The theory of exploitation as the unequal exchange of labour

    OpenAIRE

    Veneziani, Roberto; Yoshihara, Naoki

    2017-01-01

    This paper analyses the normative and positive foundations of the theory of exploitation as the unequal exchange of labour (UEL). The key intuitions behind all of the main approaches to UEL exploitation are explicitly analysed as a series of formal claims in a general economic environment. It is then argued that these intuitions can be captured by one fundamental axiom - called Labour Exploitation - which defines the basic domain of all UEL exploitation forms and identifies the formal and the...

  9. Total exploitation of an ornamental granite quarry

    Directory of Open Access Journals (Sweden)

    Taboada, J.

    2005-09-01

    Full Text Available In this paper we propose a methodology to estimate the recovery percentage for each of the products which can be obtained from the exploitation of an ornamental granite quarry: block, semiblock, masonry-transverse stone, and the smaller materials that can be used to obtain construction aggregates. This methodology ensures that quarry exploitation is exhaustive, thereby minimising the production of spoils and the consequent negative impact on the environment. The analysis is based on a detailed and exhaustive compilation of discontinuity data from the research fronts, which are then interpreted statistically and projected over the three weakness planes that are a particular feature of ornamental granite deposits. Using this information, and bearing in mind the minimum commercially viable sizes for each kind of granite, the corresponding recovery rates are calculated for each material in each plane. The results are then integrated using spatial techniques, and the result is an evaluation of quarry contents with a view to total exploitation. This methodology was applied to a quarry in the opening phase in order to carry out an a priori assessment of the economic feasibility of the quarry.

    En este trabajo se propone una metodología para estimar el porcentaje de recuperación de cada uno de los productos que se pueden obtener en la explotación de una cantera de granito ornamental: bloque, semibloque, manpostería y per piaños, y material restante destinado a la obtención de áridos. De esta manera se logra un aprovechamiento integral de la cantera, evitándose la generación de estériles y el subsiguiente impacto ambiental producido por éstos. La metodología de análisis se basa en la recopilación detallada y exhaustiva de datos de discontinuidades en los frentes de investigación, que se interpretan estadísticamente y se proyectan sobre los tres planos de debilidad propios del granito ornamental. Con esta información, y las

  10. Environmental effects of geothermal energy exploitation

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, H [Japan Metals and Chemicals Co., Ltd., Japan

    1975-01-01

    The environmental effects of geothermal power generation which cause air and water pollution and destruction of natural areas are reviewed. The production of steam and hot water affect existing hot springs sources and can cause ground subsidence. Harmful gas can be released onto the atmosphere from fumarolic gas and hot springs. Hydrothermal geothermal fields occasionally contain harmful substances such as arsenic in the hot water. Serious environmental effects can result from geothermal exploitation activities such as the felling of trees for road construction, well drilling, and plant construction. Once geothermal power generation has begun, the release of H/sub 2/S into the atmosphere and the reinjection of hot water are conducted continuously and sufficient countermeasures can be taken. One problem is the effects of plant construction and operation on natural parks. It is important to reach a compromise between development and protection of natural senic areas. Two figures, two tables, and 13 references are provided.

  11. CHARACTERISTICS OF HYDROCARBON EXPLOITATION IN ARCTIC CIRCLE

    Directory of Open Access Journals (Sweden)

    Vanja Lež

    2013-12-01

    Full Text Available The existence of large quantities of hydrocarbons is supposed within the Arctic Circle. Assumed quantities are 25% of the total undiscovered hydrocarbon reserves on Earth, mostly natural gas. Over 500 major and minor gas accumulations within the Arctic Circle were discovered so far, but apart from Snøhvit gas field, there is no commercial exploitation of natural gas from these fields. Arctic gas projects are complicated, technically hard to accomplish, and pose a great threat to the return of investment, safety of people and equipment and for the ecosystem. Russia is a country that is closest to the realization of the Arctic gas projects that are based on the giant gas fields. The most extreme weather conditions in the seas around Greenland are the reason why this Arctic region is the least explored and furthest from the realization of any gas project (the paper is published in Croatian .

  12. Protocol to Exploit Waiting Resources for UASNs

    Directory of Open Access Journals (Sweden)

    Li-Ling Hung

    2016-03-01

    Full Text Available The transmission speed of acoustic waves in water is much slower than that of radio waves in terrestrial wireless sensor networks. Thus, the propagation delay in underwater acoustic sensor networks (UASN is much greater. Longer propagation delay leads to complicated communication and collision problems. To solve collision problems, some studies have proposed waiting mechanisms; however, long waiting mechanisms result in low bandwidth utilization. To improve throughput, this study proposes a slotted medium access control protocol to enhance bandwidth utilization in UASNs. The proposed mechanism increases communication by exploiting temporal and spatial resources that are typically idle in order to protect communication against interference. By reducing wait time, network performance and energy consumption can be improved. A performance evaluation demonstrates that when the data packets are large or sensor deployment is dense, the energy consumption of proposed protocol is less than that of existing protocols as well as the throughput is higher than that of existing protocols.

  13. Exploitation of heterogeneous resources for ATLAS Computing

    CERN Document Server

    Chudoba, Jiri; The ATLAS collaboration

    2018-01-01

    LHC experiments require significant computational resources for Monte Carlo simulations and real data processing and the ATLAS experiment is not an exception. In 2017, ATLAS exploited steadily almost 3M HS06 units, which corresponds to about 300 000 standard CPU cores. The total disk and tape capacity managed by the Rucio data management system exceeded 350 PB. Resources are provided mostly by Grid computing centers distributed in geographically separated locations and connected by the Grid middleware. The ATLAS collaboration developed several systems to manage computational jobs, data files and network transfers. ATLAS solutions for job and data management (PanDA and Rucio) were generalized and now are used also by other collaborations. More components are needed to include new resources such as private and public clouds, volunteers' desktop computers and primarily supercomputers in major HPC centers. Workflows and data flows significantly differ for these less traditional resources and extensive software re...

  14. Geometric saliency to characterize radar exploitation performance

    Science.gov (United States)

    Nolan, Adam; Keserich, Brad; Lingg, Andrew; Goley, Steve

    2014-06-01

    Based on the fundamental scattering mechanisms of facetized computer-aided design (CAD) models, we are able to define expected contributions (EC) to the radar signature. The net result of this analysis is the prediction of the salient aspects and contributing vehicle morphology based on the aspect. Although this approach does not provide the fidelity of an asymptotic electromagnetic (EM) simulation, it does provide very fast estimates of the unique scattering that can be consumed by a signature exploitation algorithm. The speed of this approach is particularly relevant when considering the high dimensionality of target configuration variability due to articulating parts which are computationally burdensome to predict. The key scattering phenomena considered in this work are the specular response from a single bounce interaction with surfaces and dihedral response formed between the ground plane and vehicle. Results of this analysis are demonstrated for a set of civilian target models.

  15. Exploitation and use of coal field gas

    Energy Technology Data Exchange (ETDEWEB)

    Wang, K; Li, Z; Sun, Q

    1982-04-25

    There are slightly more than 440 mine shafts in the world from which gas is pumped at the same time coal is being mined, the volume pumped being 3.125 billion cubic meters. All the countries of the world today widely use gas as a fuel and as a raw material for the chemical industry. In China 40 percent of the total number of mine shafts are high gas mine shafts. In China, gas is used largely as fuel by the people, to fire boilers, to make formaldehyde, and to make carbon ink. Prospects are good for the exploitation of mine shaft gas that is produced in association with coal. Mine shaft gas is a top quality energy source with an extraction life that is longer than coals. (DP)

  16. Summary of radiation protection in exploitation

    International Nuclear Information System (INIS)

    Garcier, Yves; Guers, Rene; Bidard, Francoise; Colson, Philippe; Gonin, Michele; Delabre, Herve; Hemidy, Pierre-Yves; Corgnet, Bruno; Perrin, Marie-Claire; Phan Hoang, Long; Abela, Gonzague; Crepieux, Virginie; Guyot, Pierre; Haranger, Didier; Warembourg, Philippe

    2004-01-01

    This document proposes a large and detailed overview of notions and practices regarding radiation protection in relationship with an NPP exploitation framework. It presents the main notions: matter structure, radioactivity, interactions between matter and radiations, types of ionizing radiation, magnitudes and measurement units, exposure modes, main principles of radiation protection, means of protection against internal and external exposures. The second part proposes an overview of the origin of radiological risks in a nuclear power plant. This origin can be found in fission products, activation products, actinides, designed protections, or circuit contaminations. These radiological risks are more precisely identified and described in terms of detection and prevention (internal exposure risk, contamination risk, iodine-related risk, alpha radiation-related risk, access to the reactor building). The next part addresses the medical and radiological follow-up of exposed workers by a special medical control, by an individual exposure control, by a specific control of female personnel, and by attention to exceptional exposures. Measurement means are presented (detection principles, installation continuous control, workspaces control, personnel contamination control, follow-up of individual dose) as well as collective and individual protection means. The management of radiation protection is addressed through a presentation of decision and management structures for radiation protection, and of EDF objectives and ambitions in this domain. The organization of radiation protection during exploitation is described: responsibilities for radiation protection in a nuclear power station, requirements for workers, preparation of interventions in controlled zone, work execution in controlled zone, zone controls and radiological cleanness of installations. The two last chapters address issues and practices of radiation protection in the case of deconstruction or dismantling, and

  17. Distribution of monoclonal antibody subgroups and sequence-based types among Legionella pneumophila serogroup 1 isolates derived from cooling tower water, bathwater, and soil in Japan.

    Science.gov (United States)

    Amemura-Maekawa, Junko; Kikukawa, Kiyomi; Helbig, Jürgen H; Kaneko, Satoko; Suzuki-Hashimoto, Atsuko; Furuhata, Katsunori; Chang, Bin; Murai, Miyo; Ichinose, Masayuki; Ohnishi, Makoto; Kura, Fumiaki

    2012-06-01

    Legionella pneumophila serogroup (SG) 1 is the most frequent cause of legionellosis. This study analyzed environmental isolates of L. pneumophila SG 1 in Japan using monoclonal antibody (MAb) typing and sequence-based typing (SBT). Samples were analyzed from bathwater (BW; n = 50), cooling tower water (CT; n = 50), and soil (SO; n = 35). The distribution of MAb types varied by source, with the most prevalent types being Bellingham (42%), Oxford (72%), and OLDA (51%) in BW, CT, and SO, respectively. The ratios of MAb 3/1 positive isolates were 26, 2, and 14% from BW, CT, and SO, respectively. The environmental isolates from BW, CT, and SO were divided into 34 sequence types (STs; index of discrimination [IOD] = 0.973), 8 STs (IOD = 0.448), and 11 STs (IOD = 0.879), respectively. Genetic variation among CT isolates was smaller than seen in BW and SO. ST1 accounted for 74% of the CT isolates. The only common STs between (i) BW and CT, (ii) BW and SO, and (iii) CT and SO were ST1, ST129, and ST48, respectively, suggesting that each environment constitutes an independent habitat.

  18. Proba-V Mission Exploitation Platform

    Science.gov (United States)

    Goor, E.

    2017-12-01

    VITO and partners developed the Proba-V Mission Exploitation Platform (MEP) as an end-to-end solution to drastically improve the exploitation of the Proba-V (an EC Copernicus contributing mission) EO-data archive, the past mission SPOT-VEGETATION and derived vegetation parameters by researchers, service providers (e.g. the EC Copernicus Global Land Service) and end-users. The analysis of time series of data (PB range) is addressed, as well as the large scale on-demand processing of near real-time data on a powerful and scalable processing environment. New features are still developed, but the platform is yet fully operational since November 2016 and offers A time series viewer (browser web client and API), showing the evolution of Proba-V bands and derived vegetation parameters for any country, region, pixel or polygon defined by the user. Full-resolution viewing services for the complete data archive. On-demand processing chains on a powerfull Hadoop/Spark backend. Virtual Machines can be requested by users with access to the complete data archive mentioned above and pre-configured tools to work with this data, e.g. various toolboxes and support for R and Python. This allows users to immediately work with the data without having to install tools or download data, but as well to design, debug and test applications on the platform. Jupyter Notebooks is available with some examples python and R projects worked out to show the potential of the data. Today the platform is already used by several international third party projects to perform R&D activities on the data, and to develop/host data analysis toolboxes. From the Proba-V MEP, access to other data sources such as Sentinel-2 and landsat data is also addressed. Selected components of the MEP are also deployed on public cloud infrastructures in various R&D projects. Users can make use of powerful Web based tools and can self-manage virtual machines to perform their work on the infrastructure at VITO with access to

  19. Mission Exploitation Platform PROBA-V

    Science.gov (United States)

    Goor, Erwin

    2016-04-01

    VITO and partners developed an end-to-end solution to drastically improve the exploitation of the PROBA-V EO-data archive (http://proba-v.vgt.vito.be/), the past mission SPOT-VEGETATION and derived vegetation parameters by researchers, service providers and end-users. The analysis of time series of data (+1PB) is addressed, as well as the large scale on-demand processing of near real-time data. From November 2015 an operational Mission Exploitation Platform (MEP) PROBA-V, as an ESA pathfinder project, will be gradually deployed at the VITO data center with direct access to the complete data archive. Several applications will be released to the users, e.g. - A time series viewer, showing the evolution of PROBA-V bands and derived vegetation parameters for any area of interest. - Full-resolution viewing services for the complete data archive. - On-demand processing chains e.g. for the calculation of N-daily composites. - A Virtual Machine will be provided with access to the data archive and tools to work with this data, e.g. various toolboxes and support for R and Python. After an initial release in January 2016, a research platform will gradually be deployed allowing users to design, debug and test applications on the platform. From the MEP PROBA-V, access to Sentinel-2 and landsat data will be addressed as well, e.g. to support the Cal/Val activities of the users. Users can make use of powerful Web based tools and can self-manage virtual machines to perform their work on the infrastructure at VITO with access to the complete data archive. To realise this, private cloud technology (openStack) is used and a distributed processing environment is built based on Hadoop. The Hadoop ecosystem offers a lot of technologies (Spark, Yarn, Accumulo, etc.) which we integrate with several open-source components. The impact of this MEP on the user community will be high and will completely change the way of working with the data and hence open the large time series to a larger

  20. Relationship between exploitation, oscillation, MSY and extinction.

    Science.gov (United States)

    Ghosh, Bapan; Kar, T K; Legovic, T

    2014-10-01

    We give answers to two important problems arising in current fisheries: (i) how maximum sustainable yield (MSY) policy is influenced by the initial population level, and (ii) how harvesting, oscillation and MSY are related to each other in prey-predator systems. To examine the impact of initial population on exploitation, we analyze a single species model with strong Allee effect. It is found that even when the MSY exists, the dynamic solution may not converge to the equilibrium stock if the initial population level is higher but near the critical threshold level. In a prey-predator system with Allee effect in the prey species, the initial population does not have such important impact neither on MSY nor on maximum sustainable total yield (MSTY). However, harvesting the top predator may cause extinction of all species if odd number of trophic levels exist in the ecosystem. With regard to the second problem, we study two prey-predator models and establish that increasing harvesting effort either on prey, predator or both prey and predator destroys previously existing oscillation. Moreover, equilibrium stock both at MSY and MSTY level is stable. We also discuss the validity of found results to other prey-predator systems. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Exploiting Virtualization and Cloud Computing in ATLAS

    International Nuclear Information System (INIS)

    Harald Barreiro Megino, Fernando; Van der Ster, Daniel; Benjamin, Doug; De, Kaushik; Gable, Ian; Paterson, Michael; Taylor, Ryan; Hendrix, Val; Vitillo, Roberto A; Panitkin, Sergey; De Silva, Asoka; Walker, Rod

    2012-01-01

    The ATLAS Computing Model was designed around the concept of grid computing; since the start of data-taking, this model has proven very successful in the federated operation of more than one hundred Worldwide LHC Computing Grid (WLCG) sites for offline data distribution, storage, processing and analysis. However, new paradigms in computing, namely virtualization and cloud computing, present improved strategies for managing and provisioning IT resources that could allow ATLAS to more flexibly adapt and scale its storage and processing workloads on varied underlying resources. In particular, ATLAS is developing a “grid-of-clouds” infrastructure in order to utilize WLCG sites that make resources available via a cloud API. This work will present the current status of the Virtualization and Cloud Computing R and D project in ATLAS Distributed Computing. First, strategies for deploying PanDA queues on cloud sites will be discussed, including the introduction of a “cloud factory” for managing cloud VM instances. Next, performance results when running on virtualized/cloud resources at CERN LxCloud, StratusLab, and elsewhere will be presented. Finally, we will present the ATLAS strategies for exploiting cloud-based storage, including remote XROOTD access to input data, management of EC2-based files, and the deployment of cloud-resident LCG storage elements.

  2. Exploiting intrinsic fluctuations to identify model parameters.

    Science.gov (United States)

    Zimmer, Christoph; Sahle, Sven; Pahle, Jürgen

    2015-04-01

    Parameterisation of kinetic models plays a central role in computational systems biology. Besides the lack of experimental data of high enough quality, some of the biggest challenges here are identification issues. Model parameters can be structurally non-identifiable because of functional relationships. Noise in measured data is usually considered to be a nuisance for parameter estimation. However, it turns out that intrinsic fluctuations in particle numbers can make parameters identifiable that were previously non-identifiable. The authors present a method to identify model parameters that are structurally non-identifiable in a deterministic framework. The method takes time course recordings of biochemical systems in steady state or transient state as input. Often a functional relationship between parameters presents itself by a one-dimensional manifold in parameter space containing parameter sets of optimal goodness. Although the system's behaviour cannot be distinguished on this manifold in a deterministic framework it might be distinguishable in a stochastic modelling framework. Their method exploits this by using an objective function that includes a measure for fluctuations in particle numbers. They show on three example models, immigration-death, gene expression and Epo-EpoReceptor interaction, that this resolves the non-identifiability even in the case of measurement noise with known amplitude. The method is applied to partially observed recordings of biochemical systems with measurement noise. It is simple to implement and it is usually very fast to compute. This optimisation can be realised in a classical or Bayesian fashion.

  3. Fostering the Exploitation of Open Educational Resources

    Directory of Open Access Journals (Sweden)

    Thomas Richter

    2014-07-01

    Full Text Available The central concept behind Open Educational Resources (OER is opening up the access to educational resources for stakeholders who are not the usual target user group. This concept must be perceived as innovative because it describes a general economic and social paradigm shift: Education, which formerly was limited to a specific group of learners, now, is promoted as a public good. However, despite very good intentions, internationally agreed quality standards, and the availability of the required technological infrastructure, the critical threshold is not yet met. Due to several reasons, the usefulness of OER is often limited to the originally targeted context. Questions arise if the existing quality standards for Technology Enhanced Learning (TEL actually meet the specific requirements within the OER value chain, if the existing quality standards are applicable to OER in a meaningful way, and under which conditions related standards generally could support the exploitation of OER.We analyze quality standards for TEL and contrast the life cycle model of commercial learning resources against the life cycle model of OER. We investigate special demands on quality from the context of OER and, taking the former results into account, derive emergent quality criteria for OER. The paper concludes with recommendations for the design of OER and a future standard development.

  4. Exploiting Genetic Interference for Antiviral Therapy.

    Directory of Open Access Journals (Sweden)

    Elizabeth J Tanner

    2016-05-01

    Full Text Available Rapidly evolving viruses are a major threat to human health. Such viruses are often highly pathogenic (e.g., influenza virus, HIV, Ebola virus and routinely circumvent therapeutic intervention through mutational escape. Error-prone genome replication generates heterogeneous viral populations that rapidly adapt to new selection pressures, leading to resistance that emerges with treatment. However, population heterogeneity bears a cost: when multiple viral variants replicate within a cell, they can potentially interfere with each other, lowering viral fitness. This genetic interference can be exploited for antiviral strategies, either by taking advantage of a virus's inherent genetic diversity or through generating de novo interference by engineering a competing genome. Here, we discuss two such antiviral strategies, dominant drug targeting and therapeutic interfering particles. Both strategies harness the power of genetic interference to surmount two particularly vexing obstacles-the evolution of drug resistance and targeting therapy to high-risk populations-both of which impede treatment in resource-poor settings.

  5. Radiation protection in exploitation of uranium ores

    International Nuclear Information System (INIS)

    Pavlov, I.V.; Shalaev, I.L.

    1976-01-01

    The results are analyzed of the study of the radiation conditions in uranium mines, design and testing of protection means, improvement of methods and equipment for the dosimetric control in different countries since 1968 to 1975. There are outlined radiation hazards and their role in the formation of the radiation situation in mines, dispersive composition of aerosols of short-living daughter products of Rn(DPR) in the mine atmosphere. Among means of the radiation protection the following are dealt with: ventilation including the calculation of air requirements, design of ventilation systems, ventilation practices in working mines; lowering of the release of radon into the mine atmosphere by isolating non-exploited pits, application of gas-proof covers to cofferdams in faces of jointing zones, intensification of mining works in dangerous zones. Methods of air cleaning to remove Rn are suggested in brief. Apparatus are described for the individual control of the level of latent energy in the zone of miners' respiration: track dosimeters, thermoluminescent crystalls (TLC), photographic films, semiconductor systems and biophysical methods of the control for uranium mines. The efficient use of existing protection means provides the normal radiation situation in mines without significant additional investments

  6. Accelerating Large Data Analysis By Exploiting Regularities

    Science.gov (United States)

    Moran, Patrick J.; Ellsworth, David

    2003-01-01

    We present techniques for discovering and exploiting regularity in large curvilinear data sets. The data can be based on a single mesh or a mesh composed of multiple submeshes (also known as zones). Multi-zone data are typical to Computational Fluid Dynamics (CFD) simulations. Regularities include axis-aligned rectilinear and cylindrical meshes as well as cases where one zone is equivalent to a rigid-body transformation of another. Our algorithms can also discover rigid-body motion of meshes in time-series data. Next, we describe a data model where we can utilize the results from the discovery process in order to accelerate large data visualizations. Where possible, we replace general curvilinear zones with rectilinear or cylindrical zones. In rigid-body motion cases we replace a time-series of meshes with a transformed mesh object where a reference mesh is dynamically transformed based on a given time value in order to satisfy geometry requests, on demand. The data model enables us to make these substitutions and dynamic transformations transparently with respect to the visualization algorithms. We present results with large data sets where we combine our mesh replacement and transformation techniques with out-of-core paging in order to achieve significant speed-ups in analysis.

  7. Main principles of developing exploitation models of semiconductor devices

    Science.gov (United States)

    Gradoboev, A. V.; Simonova, A. V.

    2018-05-01

    The paper represents primary tasks, solutions of which allow to develop the exploitation modes of semiconductor devices taking into account complex and combined influence of ionizing irradiation and operation factors. The structure of the exploitation model of the semiconductor device is presented, which is based on radiation and reliability models. Furthermore, it was shown that the exploitation model should take into account complex and combine influence of various ionizing irradiation types and operation factors. The algorithm of developing the exploitation model of the semiconductor devices is proposed. The possibility of creating the radiation model of Schottky barrier diode, Schottky field-effect transistor and Gunn diode is shown based on the available experimental data. The basic exploitation model of IR-LEDs based upon double AlGaAs heterostructures is represented. The practical application of the exploitation models will allow to output the electronic products with guaranteed operational properties.

  8. Transnational gestational surrogacy: does it have to be exploitative?

    Science.gov (United States)

    Kirby, Jeffrey

    2014-01-01

    This article explores the controversial practice of transnational gestational surrogacy and poses a provocative question: Does it have to be exploitative? Various existing models of exploitation are considered and a novel exploitation-evaluation heuristic is introduced to assist in the analysis of the potentially exploitative dimensions/elements of complex health-related practices. On the basis of application of the heuristic, I conclude that transnational gestational surrogacy, as currently practiced in low-income country settings (such as rural, western India), is exploitative of surrogate women. Arising out of consideration of the heuristic's exploitation conditions, a set of public education and enabled choice, enhanced protections, and empowerment reforms to transnational gestational surrogacy practice is proposed that, if incorporated into a national regulatory framework and actualized within a low income country, could possibly render such practice nonexploitative.

  9. Proba-V Mission Exploitation Platform

    Science.gov (United States)

    Goor, Erwin; Dries, Jeroen

    2017-04-01

    VITO and partners developed the Proba-V Mission Exploitation Platform (MEP) as an end-to-end solution to drastically improve the exploitation of the Proba-V (a Copernicus contributing mission) EO-data archive (http://proba-v.vgt.vito.be/), the past mission SPOT-VEGETATION and derived vegetation parameters by researchers, service providers and end-users. The analysis of time series of data (+1PB) is addressed, as well as the large scale on-demand processing of near real-time data on a powerful and scalable processing environment. Furthermore data from the Copernicus Global Land Service is in scope of the platform. From November 2015 an operational Proba-V MEP environment, as an ESA operation service, is gradually deployed at the VITO data center with direct access to the complete data archive. Since autumn 2016 the platform is operational and yet several applications are released to the users, e.g. - A time series viewer, showing the evolution of Proba-V bands and derived vegetation parameters from the Copernicus Global Land Service for any area of interest. - Full-resolution viewing services for the complete data archive. - On-demand processing chains on a powerfull Hadoop/Spark backend e.g. for the calculation of N-daily composites. - Virtual Machines can be provided with access to the data archive and tools to work with this data, e.g. various toolboxes (GDAL, QGIS, GrassGIS, SNAP toolbox, …) and support for R and Python. This allows users to immediately work with the data without having to install tools or download data, but as well to design, debug and test applications on the platform. - A prototype of jupyter Notebooks is available with some examples worked out to show the potential of the data. Today the platform is used by several third party projects to perform R&D activities on the data, and to develop/host data analysis toolboxes. In parallel the platform is further improved and extended. From the MEP PROBA-V, access to Sentinel-2 and landsat data will

  10. Exploiting Untapped Information Resources in Earth Science

    Science.gov (United States)

    Ramachandran, R.; Fox, P. A.; Kempler, S.; Maskey, M.

    2015-12-01

    One of the continuing challenges in any Earth science investigation is the amount of time and effort required for data preparation before analysis can begin. Current Earth science data and information systems have their own shortcomings. For example, the current data search systems are designed with the assumption that researchers find data primarily by metadata searches on instrument or geophysical keywords, assuming that users have sufficient knowledge of the domain vocabulary to be able to effectively utilize the search catalogs. These systems lack support for new or interdisciplinary researchers who may be unfamiliar with the domain vocabulary or the breadth of relevant data available. There is clearly a need to innovate and evolve current data and information systems in order to improve data discovery and exploration capabilities to substantially reduce the data preparation time and effort. We assert that Earth science metadata assets are dark resources, information resources that organizations collect, process, and store for regular business or operational activities but fail to utilize for other purposes. The challenge for any organization is to recognize, identify and effectively utilize the dark data stores in their institutional repositories to better serve their stakeholders. NASA Earth science metadata catalogs contain dark resources consisting of structured information, free form descriptions of data and pre-generated images. With the addition of emerging semantic technologies, such catalogs can be fully utilized beyond their original design intent of supporting current search functionality. In this presentation, we will describe our approach of exploiting these information resources to provide novel data discovery and exploration pathways to science and education communities

  11. Postural Hand Synergies during Environmental Constraint Exploitation

    Directory of Open Access Journals (Sweden)

    Cosimo Della Santina

    2017-08-01

    Full Text Available Humans are able to intuitively exploit the shape of an object and environmental constraints to achieve stable grasps and perform dexterous manipulations. In doing that, a vast range of kinematic strategies can be observed. However, in this work we formulate the hypothesis that such ability can be described in terms of a synergistic behavior in the generation of hand postures, i.e., using a reduced set of commonly used kinematic patterns. This is in analogy with previous studies showing the presence of such behavior in different tasks, such as grasping. We investigated this hypothesis in experiments performed by six subjects, who were asked to grasp objects from a flat surface. We quantitatively characterized hand posture behavior from a kinematic perspective, i.e., the hand joint angles, in both pre-shaping and during the interaction with the environment. To determine the role of tactile feedback, we repeated the same experiments but with subjects wearing a rigid shell on the fingertips to reduce cutaneous afferent inputs. Results show the persistence of at least two postural synergies in all the considered experimental conditions and phases. Tactile impairment does not alter significantly the first two synergies, and contact with the environment generates a change only for higher order Principal Components. A good match also arises between the first synergy found in our analysis and the first synergy of grasping as quantified by previous work. The present study is motivated by the interest of learning from the human example, extracting lessons that can be applied in robot design and control. Thus, we conclude with a discussion on implications for robotics of our findings.

  12. Exploiting core knowledge for visual object recognition.

    Science.gov (United States)

    Schurgin, Mark W; Flombaum, Jonathan I

    2017-03-01

    Humans recognize thousands of objects, and with relative tolerance to variable retinal inputs. The acquisition of this ability is not fully understood, and it remains an area in which artificial systems have yet to surpass people. We sought to investigate the memory process that supports object recognition. Specifically, we investigated the association of inputs that co-occur over short periods of time. We tested the hypothesis that human perception exploits expectations about object kinematics to limit the scope of association to inputs that are likely to have the same token as a source. In several experiments we exposed participants to images of objects, and we then tested recognition sensitivity. Using motion, we manipulated whether successive encounters with an image took place through kinematics that implied the same or a different token as the source of those encounters. Images were injected with noise, or shown at varying orientations, and we included 2 manipulations of motion kinematics. Across all experiments, memory performance was better for images that had been previously encountered with kinematics that implied a single token. A model-based analysis similarly showed greater memory strength when images were shown via kinematics that implied a single token. These results suggest that constraints from physics are built into the mechanisms that support memory about objects. Such constraints-often characterized as 'Core Knowledge'-are known to support perception and cognition broadly, even in young infants. But they have never been considered as a mechanism for memory with respect to recognition. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. Thermal Property Engineering: Exploiting the Properties of Ceramic Nanocomposites

    Science.gov (United States)

    2018-03-01

    ARL-TR-8308 ● MAR 2018 US Army Research Laboratory Thermal Property Engineering : Exploiting the Properties of Ceramic...return it to the originator. ARL-TR-8308 ● MAR 2018 US Army Research Laboratory Thermal Property Engineering : Exploiting the...2015 – Dec 31 2017 4. TITLE AND SUBTITLE Thermal Property Engineering : Exploiting the Properties of Ceramic Nanocomposites 5a. CONTRACT NUMBER 5b

  14. Exploiting Laboratory and Heliophysics Plasma Synergies

    Directory of Open Access Journals (Sweden)

    Jill Dahlburg

    2010-05-01

    Full Text Available Recent advances in space-based heliospheric observations, laboratory experimentation, and plasma simulation codes are creating an exciting new cross-disciplinary opportunity for understanding fast energy release and transport mechanisms in heliophysics and laboratory plasma dynamics, which had not been previously accessible. This article provides an overview of some new observational, experimental, and computational assets, and discusses current and near-term activities towards exploitation of synergies involving those assets. This overview does not claim to be comprehensive, but instead covers mainly activities closely associated with the authors’ interests and reearch. Heliospheric observations reviewed include the Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI on the National Aeronautics and Space Administration (NASA Solar Terrestrial Relations Observatory (STEREO mission, the first instrument to provide remote sensing imagery observations with spatial continuity extending from the Sun to the Earth, and the Extreme-ultraviolet Imaging Spectrometer (EIS on the Japanese Hinode spacecraft that is measuring spectroscopically physical parameters of the solar atmosphere towards obtaining plasma temperatures, densities, and mass motions. The Solar Dynamics Observatory (SDO and the upcoming Solar Orbiter with the Heliospheric Imager (SoloHI on-board will also be discussed. Laboratory plasma experiments surveyed include the line-tied magnetic reconnection experiments at University of Wisconsin (relevant to coronal heating magnetic flux tube observations and simulations, and a dynamo facility under construction there; the Space Plasma Simulation Chamber at the Naval Research Laboratory that currently produces plasmas scalable to ionospheric and magnetospheric conditions and in the future also will be suited to study the physics of the solar corona; the Versatile Toroidal Facility at the Massachusetts Institute of Technology that

  15. Simulated population responses of common carp to commercial exploitation

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Michael J.; Hennen, Matthew J.; Brown, Michael L.

    2011-12-01

    Common carp Cyprinus carpio is a widespread invasive species that can become highly abundant and impose deleterious ecosystem effects. Thus, aquatic resource managers are interested in controlling common carp populations. Control of invasive common carp populations is difficult, due in part to the inherent uncertainty of how populations respond to exploitation. To understand how common carp populations respond to exploitation, we evaluated common carp population dynamics (recruitment, growth, and mortality) in three natural lakes in eastern South Dakota. Common carp exhibited similar population dynamics across these three systems that were characterized by consistent recruitment (ages 3 to 15 years present), fast growth (K = 0.37 to 0.59), and low mortality (A = 1 to 7%). We then modeled the effects of commercial exploitation on size structure, abundance, and egg production to determine its utility as a management tool to control populations. All three populations responded similarly to exploitation simulations with a 575-mm length restriction, representing commercial gear selectivity. Simulated common carp size structure modestly declined (9 to 37%) in all simulations. Abundance of common carp declined dramatically (28 to 56%) at low levels of exploitation (0 to 20%) but exploitation >40% had little additive effect and populations were only reduced by 49 to 79% despite high exploitation (>90%). Maximum lifetime egg production was reduced from 77 to 89% at a moderate level of exploitation (40%), indicating the potential for recruitment overfishing. Exploitation further reduced common carp size structure, abundance, and egg production when simulations were not size selective. Our results provide insights to how common carp populations may respond to exploitation. Although commercial exploitation may be able to partially control populations, an integrated removal approach that removes all sizes of common carp has a greater chance of controlling population abundance

  16. Exploiting for medical and biological applications

    Science.gov (United States)

    Giano, Michael C.

    Biotherapeutics are an emerging class of drug composed of molecules ranging in sizes from peptides to large proteins. Due to their poor stability and mucosal membrane permeability, biotherapeutics are administered by a parenteral method (i.e., syringe, intravenous or intramuscular). Therapeutics delivered systemically often experience short half-lives. While, local administration may involve invasive surgical procedures and suffer from poor retention at the site of application. To compensate, the patient receives frequent doses of highly concentrated therapeutic. Unfortunately, the off-target side effects and discomfort associated with multiple injections results in poor patient compliance. Therefore, new delivery methods which can improve therapeutic retention, reduce the frequency of administration and may aid in decreasing the off-target side effects is a necessity. Hydrogels are a class of biomaterials that are gaining interests for tissue engineering and drug delivery applications. Hydrogel materials are defined as porous, 3-dimensional networks that are primarily composed of water. Generally, they are mechanically rigid, cytocompatible and easily chemically functionalized. Collectively, these properties make hydrogels fantastic candidates to perform as drug delivery depots. Current hydrogel delivery systems physically entrap the target therapeutic which is then subsequently released over time at the site of administration. The swelling and degradation of the material effect the diffusion of the therapy from the hydrogel, and therefore should be controlled. Although these strategies provide some regulation over therapeutic release, full control of the delivery is not achieved. Newer approaches are focused on designing hydrogels that exploit known interactions, covalently attach the therapy or respond to an external stimulus in an effort to gain improved control over the therapy's release. Unfortunately, the biotherapeutic is typically required to be chemically

  17. Early Sexual Exploitation as an Influence in Prostitution.

    Science.gov (United States)

    Silbert, Mimi H.; Pines, Ayala M.

    1983-01-01

    Surveyed 200 female street prostitutes to determine whether they were sexually exploited during childhood. Results showed 60 percent of the subjects were sexually exploited. The few girls who discussed their abuse with others were met with shame and most often inaction. Only 10 percent were abused by strangers. (JAC)

  18. A Descriptive Study on Sexually Exploited Children in Residential Treatment

    Science.gov (United States)

    Twill, Sarah E.; Green, Denise M.; Traylor, Amy

    2010-01-01

    Sexual exploitation and prostitution of children and adolescents is a multibillion dollar industry in the United States (Estes and Weiner in "Medical, legal & social science aspects of child sexual exploitation: A comprehensive review of pornography, prostitution, and internet crimes, vol I," G.W. Medical Publishing, Inc, St Louis,…

  19. Exploiting opportunities at all cost? Entrepreneurial intent and externalities

    NARCIS (Netherlands)

    Urbig, D.; Weitzel, G.U.; Rosenkranz, S.; van Witteloostuijn, A.

    2011-01-01

    they exploit welfare-enhancing opportunities as it is assumed in several normative models? Do we need to prevent potential entrepreneurs from being destructive or are there intrinsic limits to harm others? We experimentally investigate how people with different entrepreneurial intent exploit risky

  20. Exploitation program of ''Adamow'' quarry up to 2015

    International Nuclear Information System (INIS)

    Hadlaw, A.

    1994-01-01

    The brown coal deposits exploited by the quarry ''Adamow'' located in Central Poland are shortly described and the prognosis of their exploitation up to 2015 is given. The basis data on the perspective deposits in the quarry's area are also presented. All deposits are shown on the map. 3 ills, 2 tabs

  1. Panel discussion on exploitation of geothermal resources in thermal zones

    Energy Technology Data Exchange (ETDEWEB)

    Viramonte, J G; Mange, J; Stefani, G

    1978-03-01

    The topics discussed include the major known geothermal resources, varying ways of exploiting geothermal resources, technical and economic difficulties in the exploitation, the place of geothermal energy in the total energy policy of a given country, advanced exploration techniques, and indications of needed areas of study. The panelists represented most of the South American countries, Mexico, and Italy. (JSR)

  2. [Ecotourism exploitation model in Bita Lake Natural Reserve of Yunnan].

    Science.gov (United States)

    Yang, G; Wang, Y; Zhong, L

    2000-12-01

    Bita lake provincial natural reserve is located in Shangri-La region of North-western Yunnan, and was set as a demonstrating area for ecotourism exploitation in 1998. After a year's exploitation construction and half a year's operation as a branch of the 99' Kunming International Horticulture Exposition to accept tourists, it was proved that the ecotourism demonstrating area attained four integrated functions of ecotourism, i.e., tourism, protection, poverty clearing and environment education. Five exploitation and management models including function zoned exploitation model, featured tourism communication model signs system designing model, local Tibetan family reception model and environmental monitoring model, were also successful, which were demonstrated and spreaded to the whole province. Bita lake provincial natural reserve could be a good sample for the ecotourism exploitation natural reserves of the whole country.

  3. Rationalising predictors of child sexual exploitation and sex-trading.

    Science.gov (United States)

    Klatt, Thimna; Cavner, Della; Egan, Vincent

    2014-02-01

    Although there is evidence for specific risk factors leading to child sexual exploitation and prostitution, these influences overlap and have rarely been examined concurrently. The present study examined case files for 175 young persons who attended a voluntary organization in Leicester, United Kingdom, which supports people who are sexually exploited or at risk of sexual exploitation. Based on the case files, the presence or absence of known risk factors for becoming a sex worker was coded. Data were analyzed using t-test, logistic regression, and smallest space analysis. Users of the voluntary organization's services who had been sexually exploited exhibited a significantly greater number of risk factors than service users who had not been victims of sexual exploitation. The logistic regression produced a significant model fit. However, of the 14 potential predictors--many of which were associated with each other--only four variables significantly predicted actual sexual exploitation: running away, poverty, drug and/or alcohol use, and having friends or family members in prostitution. Surprisingly, running away was found to significantly decrease the odds of becoming involved in sexual exploitation. Smallest space analysis of the data revealed 5 clusters of risk factors. Two of the clusters, which reflected a desperation and need construct and immature or out-of-control lifestyles, were significantly associated with sexual exploitation. Our research suggests that some risk factors (e.g. physical and emotional abuse, early delinquency, and homelessness) for becoming involved in sexual exploitation are common but are part of the problematic milieu of the individuals affected and not directly associated with sex trading itself. Our results also indicate that it is important to engage with the families and associates of young persons at risk of becoming (or remaining) a sex worker if one wants to reduce the numbers of persons who engage in this activity. Copyright

  4. Meaning, function and methods of the recultivation in mining exploitation

    OpenAIRE

    Dambov, Risto; Ljatifi, Ejup

    2015-01-01

    With the exploitation of mineral resources is performed degradation and deformation of the relief and the general part of surface of the Earth's crust. Depending on the type of open pit mine, this degradation can be expressed to a lesser or greater extent, and sometimes in several square kilometers. The exploitation of mineral resources is with unbreakable link with the environment. Very often it is said that mining is „enemy No. 1“ for environment. With exploitation comes to degradation of h...

  5. The possibilities of exploitation of Serbian thermomineral waters

    International Nuclear Information System (INIS)

    Jovanovic, L.

    2002-01-01

    Global ecological problem of petrol resources deficit caused an intensive search of alternative energy sources. Deficit of conventional energy fluids in Yugoslavia requires serious efforts to create a program of alternative energy sources exploitation. Geothermal energy represents an important energetic source for the countries with poor energy resources. Geothermal energy can become the basis for economic development. At present these geothermal resources are not being exploited in Yugoslavia. The possibilities of effective exploitation of thermal and thermomineral water resources in Yugoslavia are presented in this paper

  6. Imouraren mining exploitation : Complementary studies Synthetic report Volum B - Mines

    International Nuclear Information System (INIS)

    1980-01-01

    The object of the current study is to determine the main technical characteristics of the reference project of a mine that can supply the necessary ore quantity at a production of 3000 tonnes uranium per year, along 10 years. The project is one of the possible solutions for exploiting the mine. The current study permits to establish : investment and functioning cost estimation, overall project of the mining exploitation program, necessary strength estimation, average ore grades evaluation and variations of these grades, utilities needs, production vizing program, main exploitation methods and necessary materials. Reference project study of the mine serves as base to the economics studies and studies optimization [fr

  7. Conflicts Related to Natural Resources Exploitation: A Case Study of ...

    African Journals Online (AJOL)

    Conflicts Related to Natural Resources Exploitation: A Case Study of Oil Crisis in Nigeria's Niger Delta Region and its Socio-Political and Economic Implications. ... on the environment leading to pollution of land, rivers, creeks and waterways.

  8. Exploitation of unconventional protein sources in the feed of weaner ...

    African Journals Online (AJOL)

    Exploitation of unconventional protein sources in the feed of weaner rabbits ... as protein sources for feeding ruminants but rarely considered as feed for micro ... 26.88 g/100g DM in Centrosema pubescens and Moringa oleifera, respectively.

  9. Exploiting Formation Flying for Fuel Saving Supersonic Oblique Wing Aircraft

    Science.gov (United States)

    2007-07-01

    used and developed during recent wing / winglet / morphing design programmes (Refs.13-14). By exploiting this method, we have assessed the aerodynamics ...parameters, Propulsion Issues, Size Issues, Aero-elastic effects 15. SUBJECT TERMS EOARD, Control System, Aerodynamics 16...

  10. Human trafficking and exploitation: A global health concern.

    Science.gov (United States)

    Zimmerman, Cathy; Kiss, Ligia

    2017-11-01

    In this collection review, Cathy Zimmerman and colleague introduce the PLOS Medicine Collection on Human Trafficking, Exploitation and Health, laying out the magnitude of the global trafficking problem and offering a public health policy framework to guide responses to trafficking.

  11. Uncertainty avoidance and the exploration-exploitation trade-off

    NARCIS (Netherlands)

    Broekhuizen, Thijs; Giarratana, Marco S.; Torres, Anna

    2017-01-01

    Purpose - This study aims to investigate how a firm's uncertainty avoidance - as indicated by the headquarters' national culture - impacts firm performance by affecting exploratory (product innovation) and exploitative (brand trademark protection) activities. It aims to show that firms characterized

  12. Enhanced surrogate models for statistical design exploiting space mapping technology

    DEFF Research Database (Denmark)

    Koziel, Slawek; Bandler, John W.; Mohamed, Achmed S.

    2005-01-01

    We present advances in microwave and RF device modeling exploiting Space Mapping (SM) technology. We propose new SM modeling formulations utilizing input mappings, output mappings, frequency scaling and quadratic approximations. Our aim is to enhance circuit models for statistical analysis...

  13. Trajectories and cycles of sexual exploitation and trafficking for sexual exploitation of women in the Peruvian Amazon

    OpenAIRE

    Mujica, Jaris

    2015-01-01

    The commercial sexual exploitation is a constant activity in the Peruvian Amazon. Around the river port of Pucallpa in ucayali region, the practice appears systematically: teenage attend taverns around the port, and those dedicated to the work of cooking camps logging, are victims of constant exploitation and many also of trafficking. this article aims to reconstruct the path of life and reproductive cycle of the forms of exploitation in a sample of 20 women, and focuses on: (i) evidence of s...

  14. Escaping from the exploitation trap by shaping the digital future

    OpenAIRE

    Füzes, Péter; Gódor, Zoltán; Szabó, Zsolt Roland

    2017-01-01

    Even Fortune 500 firms can disappear quickly, because many of them falls into an exploitation trap. Examples show that certain organizations – that manifest ambidextrous features – can avoid the exploitation trap. But, how can they do it? Authors tracked the digital transformation of a Fortune 500 company in order to understand the strategic and organizational challenges and solutions to become resilient and prosperous. A cutting edge example is shown in the paper about how an industry leader...

  15. The concept of exploitation in international human trafficking law

    OpenAIRE

    von der Pütten, Tuija Kaarina

    2017-01-01

    Human trafficking is commonly known as a criminal practice that takes place in the framework of sex trade: women and children are trafficked within a state, or from one state to another, for the purpose of sexual exploitation. Similarly, the early 20th century international conventions aimed to tackle ‘white slave traffic’, trafficking of women and children for sexual exploitation. However, it is misleading to see trafficking only within this context. People are trafficked so that they can be...

  16. From Exploitation to Industry: Definitions, Risks, and Consequences of Domestic Sexual Exploitation and Sex Work Among Women and Girls

    OpenAIRE

    Gerassi, Lara

    2015-01-01

    In the last 15 years, terms such as prostitution, sex trafficking, sexual exploitation, modern-day slavery, and sex work have elicited much confusion and debate as to their definitions. Consequently several challenges have emerged for both law enforcement in the prosecution of criminals and practitioners in service provision. This article reviews the state of the literature with regard to domestic, sexual exploitation among women and girls in the United States and seeks to (1) provide definit...

  17. Rational Exploitation and Utilizing of Groundwater in Jiangsu Coastal Area

    Science.gov (United States)

    Kang, B.; Lin, X.

    2017-12-01

    Jiangsu coastal area is located in the southeast coast of China, where is a new industrial base and an important coastal and Land Resources Development Zone of China. In the areas with strong human exploitation activities, regional groundwater evolution is obviously affected by human activities. In order to solve the environmental geological problems caused by groundwater exploitation fundamentally, we must find out the forming conditions of regional groundwater hydrodynamic field, and the impact of human activities on groundwater hydrodynamic field evolution and hydrogeochemical evolition. Based on these results, scientific management and reasonable exploitation of the regional groundwater resources can be provided for the utilization. Taking the coastal area of Jiangsu as the research area, we investigate and analyze of the regional hydrogeological conditions. The numerical simulation model of groundwater flow was established according to the water power, chemical and isotopic methods, the conditions of water flow and the influence of hydrodynamic field on the water chemical field. We predict the evolution of regional groundwater dynamics under the influence of human activities and climate change and evaluate the influence of groundwater dynamic field evolution on the environmental geological problems caused by groundwater exploitation under various conditions. We get the following conclusions: Three groundwater exploitation optimal schemes were established. The groundwater salinization was taken as the primary control condition. The substitution model was proposed to model groundwater exploitation and water level changes by BP network method.Then genetic algorithm was used to solve the optimization solution. Three groundwater exploitation optimal schemes were submit to local water resource management. The first sheme was used to solve the groundwater salinization problem. The second sheme focused on dual water supply. The third sheme concerned on emergency water

  18. Exploitation and Utilization of Oilfield Geothermal Resources in China

    Directory of Open Access Journals (Sweden)

    Shejiao Wang

    2016-09-01

    Full Text Available Geothermal energy is a clean, green renewable resource, which can be utilized for power generation, heating, cooling, and could effectively replace oil, gas, and coal. In recent years, oil companies have put more efforts into exploiting and utilizing geothermal energy with advanced technologies for heat-tracing oil gathering and transportation, central heating, etc., which has not only reduced resource waste, but also improved large-scale and industrial resource utilization levels, and has achieved remarkable economic and social benefits. Based on the analysis of oilfield geothermal energy development status, resource potential, and exploitation and utilization modes, the advantages and disadvantages of harnessing oilfield geothermal resource have been discussed. Oilfield geothermal energy exploitation and utilization have advantages in resources, technical personnel, technology, and a large number of abandoned wells that could be reconstructed and utilized. Due to the high heat demand in oilfields, geothermal energy exploitation and utilization can effectively replace oil, gas, coal, and other fossil fuels, and has bright prospects. The key factors limiting oilfield geothermal energy exploitation and utilization are also pointed out in this paper, including immature technologies, lack of overall planning, lack of standards in resource assessment, and economic assessment, lack of incentive policies, etc.

  19. High-throughput typing method to identify a non-outbreak-involved Legionella pneumophila strain colonizing the entire water supply system in the town of Rennes, France.

    Science.gov (United States)

    Sobral, D; Le Cann, P; Gerard, A; Jarraud, S; Lebeau, B; Loisy-Hamon, F; Vergnaud, G; Pourcel, C

    2011-10-01

    Two legionellosis outbreaks occurred in the city of Rennes, France, during the past decade, requiring in-depth monitoring of Legionella pneumophila in the water network and the cooling towers in the city. In order to characterize the resulting large collection of isolates, an automated low-cost typing method was developed. The multiplex capillary-based variable-number tandem repeat (VNTR) (multiple-locus VNTR analysis [MLVA]) assay requiring only one PCR amplification per isolate ensures a high level of discrimination and reduces hands-on and time requirements. In less than 2 days and using one 4-capillary apparatus, 217 environmental isolates collected between 2000 and 2009 and 5 clinical isolates obtained during outbreaks in 2000 and 2006 in Rennes were analyzed, and 15 different genotypes were identified. A large cluster of isolates with closely related genotypes and representing 77% of the population was composed exclusively of environmental isolates extracted from hot water supply systems. It was not responsible for the known Rennes epidemic cases, although strains showing a similar MLVA profile have regularly been involved in European outbreaks. The clinical isolates in Rennes had the same genotype as isolates contaminating a mall's cooling tower. This study further demonstrates that unknown environmental or genetic factors contribute to the pathogenicity of some strains. This work illustrates the potential of the high-throughput MLVA typing method to investigate the origin of legionellosis cases by allowing the systematic typing of any new isolate and inclusion of data in shared databases.

  20. Legionella pneumophila infection presenting as headache, confusion and dysarthria in a human immunodeficiency virus-1 (HIV-1 positive patient: case report

    Directory of Open Access Journals (Sweden)

    Robbins Nathaniel M

    2012-09-01

    Full Text Available Abstract Background Legionella pneumophila is a common cause of community-acquired pneumonia. Central nervous system dysfunction is common, and diagnosis in the absence of pulmonary symptoms can be challenging. Here we describe an atypical clinical presentation of Legionella infection in a patient with HIV who was found to have an unusual neuroradiologic lesion that further served to obscure the diagnosis. This is the first such description in a patient with Legionellosis and HIV coinfection. Case presentation A 43 year-old HIV positive man presented to our hospital with dysarthria, fevers, headache, and altered mental status. Initial work-up revealed pneumonia and a lesion of the splenium of the corpus callosum on magnetic resonance imaging. He was subsequently diagnosed with Legionella pneumonia and treated with complete symptom resolution. Conclusions Neurologic abnormalities are frequent in Legionellosis, but the diagnosis may be difficult in the absence of overt respiratory symptoms and in the presence of HIV coinfection. A high index of suspicion and early initiation of empiric antibiotics is imperative since early treatment may help prevent long-term sequelae. Neuroimaging abnormalities, though rare, can help the physician narrow down the diagnosis and avoid unnecessary invasive testing. Future studies should aim to elucidate the as yet unknown role of neuroimaging in the diagnoses and prognostication of Legionellosis, as well as the interaction between Legionella infection and HIV.

  1. Sexual exploitation and labor during adolescence: A case study

    Directory of Open Access Journals (Sweden)

    Luciana Dutra-Thomé

    2011-09-01

    Full Text Available The present article focused on the perception of sexual exploitation as a job, using a single case study design. The aim of the study was to investigate the case of a 14 year-old girl, involved in commercial sexual exploitation, who considered this situation as her labor activity. A content analysis showed protective and risk factors as categories, especially related to her labor activities. The girl perceived the sexual exploitation activity as a job that provided autonomy, subsistence, and survival. The study revealed that the negative effects of working during adolescence may bring consequences to health and development. Youth work may be defined as a risk factor, especially when the labour conditions are not adequate and protected.

  2. Information source exploitation/exploration and NPD decision-making

    DEFF Research Database (Denmark)

    Jespersen, Kristina Risom

    different Scandinavian companies. Data was analyzed using hierarchical regression models across decision criteria dimensions and NPD stages as well as analyzing the combination of selected information sources. Rather than forwarding one optimal search behavior for the entire NPD process, we find optimal...... information search behavior at either end of the exploitation/exploration continuum. Additionally, we find that overexploitation and overexploration is caused by managerial bias. This creates managerial misbehavior at gate decision-points of the NPD process.......The purpose of this study is to examine how the exploration/exploitation continuum is applied by decision-makers in new product gate decision-making. Specifically, we analyze at gate decision-points how the evaluation of a new product project is affected by the information source exploitation...

  3. The ALARA project of the EDF nuclear park exploitation

    International Nuclear Information System (INIS)

    Potoczek, J.

    1998-01-01

    To bring the exploitation of the nuclear park of EDF at the level of the best exploiters in the world in matter of collective and individual dosimetry, the ALARA principle coordinates numerous actions: to associate the temporary societies, to define common language, methods and tools for the whole park to organize a level effect in this area, to optimize the maintenance that is expansive in radiation doses, to make the different levels of management responsible on dosimetric stakes, to reduce the singular sources of exposure, to assure the organisation and exploitation of the experience back in this field and adapt consequently the system of information. The results are cheerful and the objectives for 2000 are: less than 1.2 h.Sv by year and by reactor, no intervener whom annual radiation dose is upper than 20 mSv (out of exceptional case). (N.C.)

  4. The exploitation of swamp plants for dewatering liquid sewage sludge

    Directory of Open Access Journals (Sweden)

    Jiří Šálek

    2006-01-01

    Full Text Available The operators of little rural wastewater treatment plants have been interested in economic exploitation of sewage sludge in local conditions. The chance is searching simply and natural ways of processing and exploitation stabilized sewage sludge in agriculture. Manure substrate have been obtained by composting waterless sewage sludge including rest plant biomass after closing 6–8 years period of filling liquid sewage sludge to the basin. Main attention was focused on exploitation of swamp plants for dewatering liquid sewage sludge and determination of influence sewage sludge on plants, intensity and course of evapotranspiration and design and setting of drying beds. On the base of determined ability of swamp plants evapotranspiration were edited suggestion solutions of design and operation sludge bed facilities in the conditions of small rural wastewater treatment plant.

  5. Cultural Work as a Site of Struggle: Freelancers and Exploitation

    Directory of Open Access Journals (Sweden)

    Nicole S. Cohen

    2012-05-01

    Full Text Available This paper argues that Marxist political economy is a useful framework for understanding contemporary conditions of cultural work. Drawing on Karl Marx’s foundational concepts, labour process theory, and a case study of freelance writers, I argue that the debate over autonomy and control in cultural work ignores exploitation in labour-capital relationships, which is a crucial process shaping cultural work. To demonstrate the benefits of this approach, I discuss two methods media firms use to extract surplus value from freelance writers: exploitation of unpaid labour time and exploitation of intellectual property through aggressive copyright regimes. I argue that a Marxist perspective can uncover the dynamics that are transforming cultural industries and workers’ experiences. From this perspective, cultural work is understood as a site of struggle.

  6. Exploiting Thread Parallelism for Ocean Modeling on Cray XC Supercomputers

    Energy Technology Data Exchange (ETDEWEB)

    Sarje, Abhinav [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jacobsen, Douglas W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Williams, Samuel W. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ringler, Todd [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Oliker, Leonid [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-05-01

    The incorporation of increasing core counts in modern processors used to build state-of-the-art supercomputers is driving application development towards exploitation of thread parallelism, in addition to distributed memory parallelism, with the goal of delivering efficient high-performance codes. In this work we describe the exploitation of threading and our experiences with it with respect to a real-world ocean modeling application code, MPAS-Ocean. We present detailed performance analysis and comparisons of various approaches and configurations for threading on the Cray XC series supercomputers.

  7. Influence of Machine Exploitation Effectiveness on Furniture Production Quality Level

    Directory of Open Access Journals (Sweden)

    Stasiak-Betlejewska Renata

    2015-12-01

    Full Text Available One of the most important factors determining the company‘s capacity to produce high quality products is the level of machinery operation effectiveness. Companies having modern machinery are characterized by high productivity. To obtain a high quality product, the equipment should be properly used, without any failure, which contributes significantly to the exploitation level increase. The modernity level and the exploitation effectiveness level for chosen machine producing furniture components in relation to the product quality level were analysed in the paper. As a result of the research findings analysis, proposals for corrective actions with regard to machinery maintenance and production processes were presented.

  8. On species preservation and Non-Cooperative Exploiters

    DEFF Research Database (Denmark)

    Kronbak, Lone Grønbæk; Lindroos, Marko

    cases where several non-cooperative exploiters are involved in mixed fisheries. This paper is targeting biodiversity preservation by setting up a two species model with the aim of ensuring both species survive harvesting of exploiters adapting a non-cooperative behaviour. The model starts out as a multi......-species model without biological dependency and is then modified to include also biological dependency. We contribute to the literature by analytically finding the limits on the number of players preserving both species including the conditions to be satisfied. For visual purposes we simulate a two species...

  9. Final Report, “Exploiting Global View for Resilience”

    Energy Technology Data Exchange (ETDEWEB)

    Chien, Andrew [Univ. of Chicago, IL (United States)

    2017-03-29

    Final technical report for the "Exploiting Global View for Resilience" project. The GVR project aims to create a new approach to portable, resilient applications. The GVR approach builds on a global view data model,, adding versioning (multi-version), user control of timing and rate (multi-stream), and flexible cross layer error signalling and recovery. With a versioned array as a portable abstraction, GVR enables application programmers to exploit deep scientific and application code insights to manage resilience (and its overhead) in a flexible, portable fashion.

  10. Fishery Development and Exploitation in South East Australia

    Directory of Open Access Journals (Sweden)

    Camilla Novaglio

    2018-04-01

    Full Text Available Understanding the full extent of past ecological changes in human-influenced marine systems is needed to inform present management policies, but is often hampered by the scarcity of information about exploitation practices and population status over the entire history of fishing. The history of commercial fishing in South East Australia is relatively recent and thus easier to document. Our aim is to reconstruct such history and to use this information to understand general patterns and consequences of fishing exploitation. Intense exploitation of marine resources arrived in South East Australia with European colonization in the early 1800s, and unregulated sealing, whaling and oyster dredging resulted in the first documented significant impact on local marine populations. Exploitation extended to demersal resources in 1915 when the trawl fishery developed. Between the early 1800s and the 1980s, some of the exploited stocks collapsed, but fishing moved further offshore and in deeper waters as technology improved and new resources became available or were discovered. This phase of fisheries expansion masked the unsustainable nature of some fishing industries, such as trawling and whaling, and postponed the need for management regulations. From the 1990s onward, an increasing awareness of the depleted nature of some fisheries led to the establishment of management strategies aiming at a more sustainable exploitation of target stocks and, from the mid-2000s onwards, management strategies were revised and improved to better address the effect of fishing on multiple components of marine ecosystems. This led to the recovery of some depleted populations and to increased habitat protection. The relatively short history of fishing exploitation and the small scale of the fishing industry in South East Australia played a significant role in limiting the magnitude of fishing impacts on local populations and helped to achieve recoveries when fisheries

  11. From Exploitation to Industry: Definitions, Risks, and Consequences of Domestic Sexual Exploitation and Sex Work Among Women and Girls.

    Science.gov (United States)

    Gerassi, Lara

    In the last 15 years, terms such as prostitution, sex trafficking, sexual exploitation, modern-day slavery, and sex work have elicited much confusion and debate as to their definitions. Consequently several challenges have emerged for both law enforcement in the prosecution of criminals and practitioners in service provision. This article reviews the state of the literature with regard to domestic, sexual exploitation among women and girls in the United States and seeks to (1) provide definitions and describe the complexity of all terms relating to domestic sexual exploitation of women and girls in the United States, (2) explore available national prevalence data according to the definitions provided, and (3) review the evidence of mental health, social, and structural risk factors at the micro-, mezzo-, and macrolevels.

  12. From Exploitation to Industry: Definitions, Risks, and Consequences of Domestic Sexual Exploitation and Sex Work Among Women and Girls

    Science.gov (United States)

    Gerassi, Lara

    2015-01-01

    In the last 15 years, terms such as prostitution, sex trafficking, sexual exploitation, modern-day slavery, and sex work have elicited much confusion and debate as to their definitions. Consequently several challenges have emerged for both law enforcement in the prosecution of criminals and practitioners in service provision. This article reviews the state of the literature with regard to domestic, sexual exploitation among women and girls in the United States and seeks to (1) provide definitions and describe the complexity of all terms relating to domestic sexual exploitation of women and girls in the United States, (2) explore available national prevalence data according to the definitions provided, and (3) review the evidence of mental health, social, and structural risk factors at the micro-, mezzo-, and macrolevels. PMID:26726289

  13. Wideband Low Noise Amplifiers Exploiting Thermal Noise Cancellation

    NARCIS (Netherlands)

    Bruccoleri, F.; Klumperink, Eric A.M.; Nauta, Bram

    2005-01-01

    Low Noise Amplifiers (LNAs) are commonly used to amplify signals that are too weak for direct processing for example in radio or cable receivers. Traditionally, low noise amplifiers are implemented via tuned amplifiers, exploiting inductors and capacitors in resonating LC-circuits. This can render

  14. Human trafficking for labour exploitation: Interpreting the crime

    NARCIS (Netherlands)

    Coster van Voorhout, J.E.B.

    2007-01-01

    The definition of human trafficking for labour exploitation, as follows from the European Council Framework Decision, proves to be unclear. Literal interpretation does not suffice, because it does not clarify all elements of what is deemed to be criminal behaviour, and hermeneutical interpretation

  15. Efficient Depth Map Compression Exploiting Segmented Color Data

    DEFF Research Database (Denmark)

    Milani, Simone; Zanuttigh, Pietro; Zamarin, Marco

    2011-01-01

    performances is still an open research issue. This paper presents a novel compression scheme that exploits a segmentation of the color data to predict the shape of the different surfaces in the depth map. Then each segment is approximated with a parameterized plane. In case the approximation is sufficiently...

  16. Bats track and exploit changes in insect pest populations

    Science.gov (United States)

    The role of bats or any generalist predator in suppressing prey populations depends on the predator’s ability to exploit available prey in space and time. Using a qPCR faecal DNA assay, we document significant association between numbers of Brazilian free-tailed bats (Tadarida brasiliensis) consumin...

  17. Describing Data Format Exploits Using Bitstream Segment Graphs

    NARCIS (Netherlands)

    Hartle, Michael; Schumann, Daniel; Botchak, Arsene; Tews, Erik; Mühlhäuser, Max

    2008-01-01

    Exploits based on data processing bugs are delivered through crafted data that seems to follow a data format, yet is altered in some way to trigger a specific bug during processing, eg. in order to execute contained malicious code. Decomposing crafted data according to the purported data format and

  18. Exploiting Patient Labour at Kew Cottages, Australia, 1887-1950

    Science.gov (United States)

    Monk, Lee-Ann

    2010-01-01

    This article examines the exploitation of patient labour at Kew Cottages, Australia's first purpose-built state institution for people with learning disabilities. Analysing historical evidence for the period 1887-1950 shows that unpaid patient labour contributed significantly to the economy of the Cottages and so to the government department of…

  19. Exploiting serological data to understand the epidemiology of foot ...

    African Journals Online (AJOL)

    Exploiting serological data to understand the epidemiology of foot-and-mouth disease virus serotypes circulating in Libya. Ibrahim Eldaghayes, Abdunaser Dayhum, Abdulwahab Kammon, Monier Sharif, Giancarlo Ferrari, Christianus Bartels, Keith Sumption, Donald P. King, Santina Grazioli, Emiliana Brocchi ...

  20. Open pit coal exploitation viability. Margarita mine. Case of study

    International Nuclear Information System (INIS)

    Veloza, Julia; Molina, Jorge; Mejia, Humberto

    2006-01-01

    This paper provides an analysis of financial viability, planning and design for the new coal open pit exploitation for La Margarita mine, with coal-resources estimated on 440.139,7 ton. Dimension, design and economic evaluation were possible by three exploitation methods: (multiple bench, open cast contour, and terraces). Net present values (NVP) were calculated: $c 817,5; $c 518,5 and $c 645,2 respectively for each method (given in million current Colombian pesos $. $c 2380 are equivalent to $us 1) and rate of return (ROR) 78,33%; 34,0% and 38,62% respectively for each method. These indicators served as a parameter to choose the multiple bench method, which should be recalculated because it was necessary to work jointly with two pits and making feasible the project. in addition a general environmental evaluation was done, which is vital for the exploitation. Important impacts on the flower, animals, air, water were found, and measures of control, prevention and mitigation were stated. it is expected that this paper can be useful as a technical-economical support for the development of the open pit exploitation in the margarita mine

  1. Exploiting wild relatives of S. lycopersicum for quality traits

    NARCIS (Netherlands)

    Víquez Zamora, A.M.

    2015-01-01

    Exploiting wild relatives of S. lycopersicum for quality traits Ana Marcela Víquez Zamora Tomatoes are consumed worldwide and became a model for crop plant research. A part of the research aims at expanding genetic diversity in tomato; this can be done by incorporating

  2. Geographical aspects of exploitation of nuclear energy in Europe

    International Nuclear Information System (INIS)

    Kurucova, S.

    2007-05-01

    The topic of exploitation of nuclear energy is becoming increasingly actual in the present time in connection with frequently discussed question of 'renaissance of nuclear energetics'. The work is aimed at research of geographical aspects of exploitation of nuclear energy for military and civil purposes on the territory of Europe. The base of work represents the analysis of theoretical aspects of research of energy, mainly of nuclear energy. The work examines the historical development of exploitation of nuclear energy since its discovery, through development of military nuclear industry in Europe, big attention is paid to spreading of nuclear energetics on the territory of Europe from its beginnings up to the present time. The main part of the work represents the analysis of the present situation of exploitation of nuclear energy for civil purposes in Europe. The attention is paid to so-called nuclear fuel cycle as complex chain of several reciprocally interconnected operations of nuclear fuel treatment. The monitoring of spatial relations among individual countries within their nuclear fuel cycles is emphasised. The analysis of historical development and of the present state of nuclear energetics finished up in the outline of the perspectives of its further development in Europe. The analysis of the tendencies of evolution of world energetic economy mentions on the trend of growth of energy consumption in the world and Europe, as well as on the important position of nuclear energy in the structure of energy sources. Summary in English language is included. (author)

  3. Exploitation of Free Markets and Globalization to Finance Terrorists

    Science.gov (United States)

    2008-09-01

    is their capability to exploit the black market peso exchange or the international foreign exchange arbitrage . Under the scenario of a weak U.S...appears legitimate. By using intermediaries or legitimate businesses, the financial markets are wide open for terrorists to hedge funds and

  4. Exploitation of commercial remote sensing images: reality ignored?

    Science.gov (United States)

    Allen, Paul C.

    1999-12-01

    The remote sensing market is on the verge of being awash in commercial high-resolution images. Market estimates are based on the growing numbers of planned commercial remote sensing electro-optical, radar, and hyperspectral satellites and aircraft. EarthWatch, Space Imaging, SPOT, and RDL among others are all working towards launch and service of one to five meter panchromatic or radar-imaging satellites. Additionally, new advances in digital air surveillance and reconnaissance systems, both manned and unmanned, are also expected to expand the geospatial customer base. Regardless of platform, image type, or location, each system promises images with some combination of increased resolution, greater spectral coverage, reduced turn-around time (request-to- delivery), and/or reduced image cost. For the most part, however, market estimates for these new sources focus on the raw digital images (from collection to the ground station) while ignoring the requirements for a processing and exploitation infrastructure comprised of exploitation tools, exploitation training, library systems, and image management systems. From this it would appear the commercial imaging community has failed to learn the hard lessons of national government experience choosing instead to ignore reality and replicate the bias of collection over processing and exploitation. While this trend may be not impact the small quantity users that exist today it will certainly adversely affect the mid- to large-sized users of the future.

  5. Human trafficking and exploitation: A global health concern.

    Directory of Open Access Journals (Sweden)

    Cathy Zimmerman

    2017-11-01

    Full Text Available In this collection review, Cathy Zimmerman and colleague introduce the PLOS Medicine Collection on Human Trafficking, Exploitation and Health, laying out the magnitude of the global trafficking problem and offering a public health policy framework to guide responses to trafficking.

  6. Six scenarios of exploiting an ontology based, mobilized learning environment

    NARCIS (Netherlands)

    Kismihók, G.; Szabó, I.; Vas, R.

    2012-01-01

    In this article, six different exploitation possibilities of an educational ontology based, mobilized learning management system are presented. The focal point of this system is the educational ontology model. The first version of this educational ontology model serves as a foundation for curriculum

  7. Risk assessment by dynamic representation of vulnerability, exploitation, and impact

    Science.gov (United States)

    Cam, Hasan

    2015-05-01

    Assessing and quantifying cyber risk accurately in real-time is essential to providing security and mission assurance in any system and network. This paper presents a modeling and dynamic analysis approach to assessing cyber risk of a network in real-time by representing dynamically its vulnerabilities, exploitations, and impact using integrated Bayesian network and Markov models. Given the set of vulnerabilities detected by a vulnerability scanner in a network, this paper addresses how its risk can be assessed by estimating in real-time the exploit likelihood and impact of vulnerability exploitation on the network, based on real-time observations and measurements over the network. The dynamic representation of the network in terms of its vulnerabilities, sensor measurements, and observations is constructed dynamically using the integrated Bayesian network and Markov models. The transition rates of outgoing and incoming links of states in hidden Markov models are used in determining exploit likelihood and impact of attacks, whereas emission rates help quantify the attack states of vulnerabilities. Simulation results show the quantification and evolving risk scores over time for individual and aggregated vulnerabilities of a network.

  8. Indicators of Nuclear safety and exploitation in ANAV

    International Nuclear Information System (INIS)

    Quintana Prieto, M.; Jorda Alcove, M.

    2013-01-01

    The use of indicators by ANAV plants, aims to be a tool to facilitate the assessment of the behaviour of the plants nuclear over a specific time period. The following are and are they explain those related to Nuclear safety and exploitation.

  9. Desiring TESOL and International Education: Market Abuse and Exploitation

    Science.gov (United States)

    Chowdhury, Raqib; Ha, Phan Le

    2014-01-01

    This book addresses how Western universities have constructed themselves as global providers of education, and are driven to be globally competitive. It examines how the term "international" has been exploited by the market in the form of government educational policies and agencies, host institutions, academia and the mass media. The…

  10. Exploiting Elementary Landscapes for TSP, Vehicle Routing and Scheduling

    Science.gov (United States)

    2015-09-03

    similar mathematical foundation to enable gradient descent methods for discrete combinatorial optimization problems. We are also generalizing our prior...research has exploited statistical and mathematical properties of elementary landscapes to develop new gradient methods for combinatorial optimization... mathematically methods to more automatically identify elementary landscapes. If a combinatorial optimization problem is a superposition of elemen

  11. 77 FR 36491 - Request for Information Regarding Senior Financial Exploitation

    Science.gov (United States)

    2012-06-19

    ... BUREAU OF CONSUMER FINANCIAL PROTECTION [Docket CFPB-2012-0018] Request for Information Regarding Senior Financial Exploitation AGENCY: Bureau of Consumer Financial Protection. ACTION: Request for Information. SUMMARY: Section 1013(g)(1) of the Dodd-Frank Wall Street Reform and Consumer Protection Act of...

  12. Features for Exploiting Black-Box Optimization Problem Structure

    DEFF Research Database (Denmark)

    Tierney, Kevin; Malitsky, Yuri; Abell, Tinus

    2013-01-01

    landscape of BBO problems and show how an algorithm portfolio approach can exploit these general, problem indepen- dent features and outperform the utilization of any single minimization search strategy. We test our methodology on data from the GECCO Workshop on BBO Benchmarking 2012, which contains 21...

  13. Assisting children born of sexual exploitation and abuse

    Directory of Open Access Journals (Sweden)

    Lauren Rumble

    2007-01-01

    Full Text Available The UN Secretary-General has issued a strategy tosupport victims of sexual exploitation and abuse by UNstaff. It includes a controversial proposal to introduceDNA sampling for all UN staff. Unless this suggestionis adopted, an important opportunity to implementa truly survivor-centred approach may be lost.

  14. Beyond the Bravado: Sex Roles and the Exploitive Male.

    Science.gov (United States)

    Taubman, Stan

    1986-01-01

    Examines the tendency of men to engage in domestic violence and sexual exploitation and presents male sex-role acquisition as a process of psychosocial violence against young boys, which creates a sense of shame, powerlessness, self-alienation, isolation from others, and retaliatory rage and inhibits capacities for intimacy and mutuality.…

  15. Grooming Cybervictims: The Psychosocial Effects of Online Exploitation for Youth.

    Science.gov (United States)

    Berson, Ilene R.

    2003-01-01

    Presents an overview of the benefits and risks of Web-based interactions for youth. Discusses, as an illustrative example, the psychosocial effects of online "grooming" practices that are designed to lure and exploit children by enticing them, typically in a nonsexual way, toward a sexual encounter. Suggests constructive solutions and a…

  16. Malware Sandbox Analysis for Secure Observation of Vulnerability Exploitation

    Science.gov (United States)

    Yoshioka, Katsunari; Inoue, Daisuke; Eto, Masashi; Hoshizawa, Yuji; Nogawa, Hiroki; Nakao, Koji

    Exploiting vulnerabilities of remote systems is one of the fundamental behaviors of malware that determines their potential hazards. Understanding what kind of propagation tactics each malware uses is essential in incident response because such information directly links with countermeasures such as writing a signature for IDS. Although recently malware sandbox analysis has been studied intensively, little work is done on securely observing the vulnerability exploitation by malware. In this paper, we propose a novel sandbox analysis method for securely observing malware's vulnerability exploitation in a totally isolated environment. In our sandbox, we prepare two victim hosts. We first execute the sample malware on one of these hosts and then let it attack the other host which is running multiple vulnerable services. As a simple realization of the proposed method, we have implemented a sandbox using Nepenthes, a low-interaction honeypot, as the second victim. Because Nepenthes can emulate a variety of vulnerable services, we can efficiently observe the propagation of sample malware. In the experiments, among 382 samples whose scan capabilities are confirmed, 381 samples successfully started exploiting vulnerabilities of the second victim. This indicates the certain level of feasibility of the proposed method.

  17. Annexe 3. Constitution d'une exploitation à Homs

    OpenAIRE

    2015-01-01

    ‘Abd al-Laṭīf, né en 1925, est jardinier à Horns. Il exploite avec son fils aîné et l'aide de deux de ses petits-fils un jardin de quelques 35 dunum (3,5 hectares) situé dans le zūr al-Ǧdīdeh, secteur central de la zone agricole. Cette grande exploitation, constituée de plusieurs parcelles ayant différents statuts, est en partie le produit d'une histoire familiale dont je voudrais présenter ici brièvement les principaux aspects. Figure 50 – Alliances matrimoniales entre la lignée de ‘Abbās e...

  18. Design and Exploitation Problems of Drill String in Directional Drilling

    Directory of Open Access Journals (Sweden)

    Bednarz Stanislaw

    2004-09-01

    Full Text Available Drill string design for directional drilling requires accounting for a number of factors. First, types and expected values of loads should be determined. Then, elements of the drill string should be so selected as to enable realization of the plan at specified loads. Some of additional factors, e. g. purchase, exploitation cost, geological conditions in the bore-hole, washing of the bore-hole, stability, trajectory, rig parameters, accuracy of gauges, pumps parameters remain in conflict. Drill pipes are made of rolled pipes, upset and welded with tool joints to 9,5 m long; the shorter ones can be made of hot forged rods. Exploitation requirements, being a result of practical experience supported by theoretical and laboratory analyses should be a part of syllabuses of technical staff educational programs. Apart from designing the string, it is also vital to lower the risk of a drilling failure. The significance of these aspects seems to be unquestionable.

  19. Environmental Impacts of Sand Exploitation. Analysis of Sand Market

    Directory of Open Access Journals (Sweden)

    Marius Dan Gavriletea

    2017-06-01

    Full Text Available Sand is an indispensable natural resource for any society. Despite society’s increasing dependence on sand, there are major challenges that this industry needs to deal with: limited sand resources, illegal mining, and environmental impact of sand mining. The purpose of this paper is twofold: to present an overview of the sand market, highlighting the main trends and actors for production, export and import, and to review the main environmental impacts associated with sand exploitation process. Based on these findings, we recommend different measures to be followed to reduce negative impacts. Sand mining should be done in a way that limits environmental damage during exploitation and restores the land after mining operations are completed.

  20. Analysis Of Damage Arising From Exploitation Of The Aircraft

    Directory of Open Access Journals (Sweden)

    Woźny Piotr

    2014-12-01

    Full Text Available During exploitation, due to a variety of reasons, aircrafts are damaged or suffer from different failures. In the process of operation, using appropriate methods of diagnosis, failure, damage, and relative deregulation of individual elements or units can be detected. For this purpose, one can apply a number of indirect diagnostic methods with the use of recorded diagnostic signals or a direct diagnosis with the use of non-destructive methods. The proper identification of the technical condition allows to determine the causes of irregularities and take actions aimed at preventing their occurrence. The article presents the types of exploitation damage of a multi-purpose aircraft. In addition, the criteria for the division of damage and research methods of the causes of damage are presented. Furthermore, an analysis of the scope of activities to be performed during the research of causes of damage to the aircraft is made.

  1. Target Localization with a Single Antenna via Directional Multipath Exploitation

    Directory of Open Access Journals (Sweden)

    Ali H. Muqaibel

    2015-01-01

    Full Text Available Target localization in urban sensing can benefit from angle dependency of the pulse shape at a radar receiver antenna. We propose a localization approach that utilizes the embedded directivity in ultra-wideband (UWB antennas to estimate target positions. A single radar unit sensing operation of indoor targets surrounded by interior walls is considered, where interior wall multipaths are exploited to provide target cross-range. This exploitation assumes resolvability of the multipath components, which is made possible by the virtue of using UWB radar signals. The proposed approach is most attractive when only few multipaths are detectable due to propagation obstructions or owing to low signal-to-noise ratios. Both simulated and experimental data are used to demonstrate the effectiveness of the proposed approach.

  2. Exploring, exploiting and evolving diversity of aquatic ecosystem models

    DEFF Research Database (Denmark)

    Janssen, Annette B G; Arhonditsis, George B.; Beusen, Arthur

    2015-01-01

    Here, we present a community perspective on how to explore, exploit and evolve the diversity in aquatic ecosystem models. These models play an important role in understanding the functioning of aquatic ecosystems, filling in observation gaps and developing effective strategies for water quality...... management. In this spirit, numerous models have been developed since the 1970s. We set off to explore model diversity by making an inventory among 42 aquatic ecosystem modellers, by categorizing the resulting set of models and by analysing them for diversity. We then focus on how to exploit model diversity...... available through open-source policies, to standardize documentation and technical implementation of models, and to compare models through ensemble modelling and interdisciplinary approaches. We end with our perspective on how the field of aquatic ecosystem modelling might develop in the next 5–10 years...

  3. Exploiting Social Media Sensor Networks through Novel Data Fusion Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Kouri, Tina [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-11-01

    Unprecedented amounts of data are continuously being generated by sensors (“hard” data) and by humans (“soft” data), and this data needs to be exploited to its full potential. The first step in exploiting this data is determine how the hard and soft data are related to each other. In this project we fuse hard and soft data, using the attributes of each (e.g., time and space), to gain more information about interesting events. Next, we attempt to use social networking textual data to predict the present (i.e., predict that an interesting event is occurring and details about the event) using data mining, machine learning, natural language processing, and text analysis techniques.

  4. Exploitation Strategies in Social Parasites of Fungus Growing Ants

    DEFF Research Database (Denmark)

    Clement, Janni Dolby

    One of the most remarkable and complex parasitic interactions is social parasitism, where a parasite exploits a complete society, rather than an individual organism. By integrating into a society the parasite gains protection against predators and diseases, and can redirect resources from the host...... to increase its own fitness. The host will use a sophisticated recognition system in order to accept nestmates and expel intruders from their societies. However this defence barrier can be overcome by parasites. Among the most specialized social parasites are the inquilines that exploit social insect colonies...... to this are Acromyrmex insinuator and Acromyrmex ameliae, parasites of fungus-growing ants. By still producing a worker caste both species offers a rare opportunity to study adaptive features in parasite worker behaviour. Furthermore can closely related inquiline-host combinations give us an insight in the trade...

  5. Do singing rock hyraxes exploit conspecific calls to gain attention?

    Directory of Open Access Journals (Sweden)

    Amiyaal Ilany

    Full Text Available Signal detection theory predicts that signals directed at distant or busy receivers in noisy backgrounds will begin with an alert component, in order to draw attention. Instead of an alert component, however, animals could get the same effect by using an external stimulus. Here we combined observations of free-living rock hyraxes (Procavia capensis with playback experiments to elucidate the circumstances under which males begin singing. We show that males sing following hyrax pup screams, which elicit a strong response from hyraxes within hearing distance, which are potential receivers. We hypothesize that singers enhance their singing display by exploiting the rarely emitted pup screams. To our knowledge, our findings are the first indication that animals may enhance signal reception by exploiting conspecifics' signals and the differential attention to these signals. We suggest that the utilization of external stimuli by signalers may be widespread, as an adaptive strategy for communication in complex environments.

  6. Host exploitation strategies of the social parasite Maculinea alcon

    DEFF Research Database (Denmark)

    Fürst, Matthias Alois

    as model systems. These enable the study of adaptations and counter-adaptations that might evolve in the arms-race between a parasite pursuing maximum gain and a host trying to avoid exploitation. One such system is the socially parasitic butterfly Maculinea alcon and its host the ant Myrmica rubra....... Throughout the first instars M. alcon lives on a specific food plant, however, in the last instar before pupation it develops into an obligate social parasite, posing a considerably cost to its host ant colony. I here focus on the different exploitation strategies of M. alcon throughout its lifecycle...... a fitness cost to infected host ant colonies, the host ants are expected to have developed defense mechanisms in response to the presence of the social parasite. I was able to demonstrate that the efficiency of ant colonies to defend themselves against intruders depends on a multitude of often correlated...

  7. Exploitation of Natural Resources and the Public Sector in Greenland

    DEFF Research Database (Denmark)

    Nielsen, Søren Bo

    This paper considers the role of the public sector in future exploitation of non-renewable resources, especially minerals, in Greenland. The focus is on fiscal sustainability, principles for public sector involvement and the form of government take from mining activities. At present, the public...... budget in Greenland is nearly in balance, but at unchanged policies and standards public expenditures relative to GDP are bound to increase dramatically over the next decades due to population ageing. At the same time, the freezing of the block grant from Denmark implies a decrease in revenues relative...... to GDP. Hence, fiscal policy is quite far from being sustainable. Apart from a need for reforms, these facts also constrain the possible role of the public sector in future resource exploitation. In any case, the government should preferably adhere to strict principles when developing the mineral sector...

  8. Evaluating Maximum Wind Energy Exploitation in Active Distribution Networks

    DEFF Research Database (Denmark)

    Siano, Pierluigi; Chen, Peiyuan; Chen, Zhe

    2010-01-01

    The increased spreading of distributed and renewable generation requires moving towards active management of distribution networks. In this paper, in order to evaluate maximum wind energy exploitation in active distribution networks, a method based on a multi-period optimal power flow (OPF......) analysis is proposed. Active network management schemes such as coordinated voltage control, energy curtailment and power factor control are integrated in the method in order to investigate their impacts on the maximization of wind energy exploitation. Some case studies, using real data from a Danish...... distribution system, confirmed the effectiveness of the proposed method in evaluating the optimal applications of active management schemes to increase wind energy harvesting without costly network reinforcement for the connection of wind generation....

  9. Exploitation of the Virtual Worlds in Tourism and Tourism Education

    Directory of Open Access Journals (Sweden)

    Zejda Pavel

    2016-12-01

    Full Text Available Academics perceive a great potential of virtual worlds in various areas, including tourism and education. Efforts adapting the virtual worlds in practice are, however, still marginal. There is no clear definition of the virtual world. Therefore the author of this article attempts to provide one. The paper also focuses on the barriers of a wider exploitation of the virtual worlds and discusses the principles that might help to increase their potential in tourism area. One of the principles – gamification – favours a wider adaptation of the virtual worlds in tourism. Applying gamification principles provides visitors with some unique experiences while serving as a powerful marketing tool for institutions. The benefits of implementing tourism education activities based on cooperative principles set in an immersive environment of the virtual worlds are depicted afterwards. Finally, this paper includes successful case studies, which show advantages and drawbacks of some approaches in exploiting the virtual worlds in tourism and tourism education.

  10. The ESA Scientific Exploitation of Operational Missions element

    Science.gov (United States)

    Desnos, Yves-Louis; Regner, Peter; Delwart, Steven; Benveniste, Jerome; Engdahl, Marcus; Zehner, Claus; Mathieu, Pierre-Philippe; Bojkov, Bojan; Gascon, Ferran; Donlon, Craig; Davidson, Malcolm; Goryl, Philippe; Pinnock, Simon

    2015-04-01

    SEOM is a program element within the fourth period (2013-2017) of ESA's Earth Observation Envelope Programme (http://seom.esa.int/). The prime objective is to federate, support and expand the international research community that the ERS,ENVISAT and the Envelope programmes have built up over the last 25 years. It aims to further strengthen the leadership of the European Earth Observation research community by enabling them to extensively exploit future European operational EO missions. SEOM will enable the science community to address new scientific research that are opened by free and open access to data from operational EO missions. Based on community-wide recommendations for actions on key research issues, gathered through a series of international thematic workshops and scientific user consultation meetings, a work plan has been established and is approved every year by ESA Members States. The 2015 SEOM work plan is covering the organisation of three Science users consultation workshops for Sentinel1/3/5P , the launch of new R&D studies for scientific exploitation of the Sentinels, the development of open-source multi-mission scientific toolboxes, the organisation of advanced international training courses, summer schools and educational materials, as well as activities for promoting the scientific use of EO data. The first SEOM projects have been tendered since 2013 including the development of Sentinel toolboxes, advanced INSAR algorithms for Sentinel-1 TOPS data exploitation, Improved Atmospheric Spectroscopic data-base (IAS), as well as grouped studies for Sentinel-1, -2, and -3 land and ocean applications and studies for exploiting the synergy between the Sentinels. The status and first results from these SEOM projects will be presented and an outlook for upcoming SEOM studies will be given.

  11. Exploitation of the Virtual Worlds in Tourism and Tourism Education

    OpenAIRE

    Zejda Pavel; Zejda David

    2016-01-01

    Academics perceive a great potential of virtual worlds in various areas, including tourism and education. Efforts adapting the virtual worlds in practice are, however, still marginal. There is no clear definition of the virtual world. Therefore the author of this article attempts to provide one. The paper also focuses on the barriers of a wider exploitation of the virtual worlds and discusses the principles that might help to increase their potential in tourism area. One of the principles – g...

  12. Exploration and Exploitation of Victorian Science in Darwin's Reading Notebooks

    OpenAIRE

    Murdock, Jaimie; Allen, Colin; DeDeo, Simon

    2015-01-01

    Search in an environment with an uncertain distribution of resources involves a trade-off between exploitation of past discoveries and further exploration. This extends to information foraging, where a knowledge-seeker shifts between reading in depth and studying new domains. To study this decision-making process, we examine the reading choices made by one of the most celebrated scientists of the modern era: Charles Darwin. From the full-text of books listed in his chronologically-organized r...

  13. Exploiting Lexical Regularities in Designing Natural Language Systems.

    Science.gov (United States)

    1988-04-01

    ELEMENT. PROJECT. TASKN Artificial Inteligence Laboratory A1A4WR NTumet 0) 545 Technology Square Cambridge, MA 02139 Ln *t- CONTROLLING OFFICE NAME AND...RO-RI95 922 EXPLOITING LEXICAL REGULARITIES IN DESIGNING NATURAL 1/1 LANGUAGE SYSTENS(U) MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE...oes.ary and ftdou.Ip hr Nl wow" L,2This paper presents the lexical component of the START Question Answering system developed at the MIT Artificial

  14. Television production, Funding Models and Exploitation of Content

    OpenAIRE

    Doyle, Gillian

    2016-01-01

    The rise of digital platforms has transformative implications for strategies of financing media production and for exploitation of the economic value in creative content. In the television industry, changes in technologies for distribution and the emergence of SVOD services such as Netflix are gradually shifting audiences and financial power away from broadcasters while at the same time creating unprecedented opportunities for programme-makers.  Drawing on findings from recent RCUK-funded res...

  15. Exploitation and Utilization of Oilfield Geothermal Resources in China

    OpenAIRE

    Shejiao Wang; Jiahong Yan; Feng Li; Junwen Hu; Kewen Li

    2016-01-01

    Geothermal energy is a clean, green renewable resource, which can be utilized for power generation, heating, cooling, and could effectively replace oil, gas, and coal. In recent years, oil companies have put more efforts into exploiting and utilizing geothermal energy with advanced technologies for heat-tracing oil gathering and transportation, central heating, etc., which has not only reduced resource waste, but also improved large-scale and industrial resource utilization levels, and has ac...

  16. Low-Level Exploitation Mitigation by Diverse Microservices

    OpenAIRE

    Otterstad , Christian; Yarygina , Tetiana

    2017-01-01

    Part 2: Microservices and Containers; International audience; This paper discusses a combination of isolatable microservices and software diversity as a mitigation technique against low-level exploitation; the effectiveness and benefits of such an architecture are substantiated. We argue that the core security benefit of microservices with diversity is increased control flow isolation. Additionally, a new microservices mitigation technique leveraging a security monitor service is introduced t...

  17. Organizational Ambidexterity : Balancing Exploitation and Exploration in Organizations

    OpenAIRE

    Yigit, Mert

    2013-01-01

    Purpose: This paper aims to investigate necessity of ambidexterity for organizations. The main interest of this thesis is to investigate why organizations should be ambidextrous and how organizations can reach ambidexterity under the pressure of limited resources and competitive market condition. Findings: This thesis explored relations and tensions between exploitation and exploration in organizational and individual aspects. Findings in the research show that communication skill of the subu...

  18. Exploiting Child-Robot Aesthetic Interaction for a Social Robot

    OpenAIRE

    Lee, Jae-Joon; Kim, Dae-Won; Kang, Bo-Yeong

    2012-01-01

    A social robot interacts and communicates with humans by using the embodied knowledge gained from interactions with its social environment. In recent years, emotion has emerged as a popular concept for designing social robots. Several studies on social robots reported an increase in robot sociability through emotional imitative interactions between the robot and humans. In this paper conventional emotional interactions are extended by exploiting the aesthetic theories that the sociability of ...

  19. Preventing Exploits Against Software of Uncertain Provenance (PEASOUP)

    Science.gov (United States)

    2015-05-01

    two common synchronization idioms: conditional variables (e.g., pthread_cond_wait()) and semaphores that count up and are used for signaling...delay prior to certain synchronization operations. The operations include thread creation, the first lock of each mutex (or decrement of a semaphore ...permissions are shared by all threads in the same process. • Synchronization Primitives . To exploit the race condition, two attacker-controlled

  20. Endangered Species and Natural Resource Exploitation: Extinction vs. Coexistence

    OpenAIRE

    Tsur, Yacov; Zemel, Amos

    1994-01-01

    The threat on the survival of animal species due to intensive use of natural resources is incorporated within resource management models, paying special attention to uncertainty regarding the conditions that lead to extinction. The manner in which the potential benefits forgone due to the species extinction (denoted extinction penalty) induce more conservative exploitation policies is studied in detail. When the extinction penalty is ignored, the optimal policy is to drive the resource stock ...

  1. An Equity Centered Management Approach to Exploiting Sport Employee Productivity

    OpenAIRE

    Schneider, Robert C.

    2017-01-01

    A primary goal ofsport organizations is to exploit employees’ abilities to their fullestcapacities. Sport managers who successfully maximize employee productivity willgreatly increase the chances of achieving the organization’s goals andobjectives. The full potential of sport employees’ abilities can be realizedthrough the application of the equity component grounded in Adam’s EquityTheory (Adams, 1963). Centered on the premise that the relationship betweensport manager and employer must be o...

  2. Exploiting GPUs in Virtual Machine for BioCloud

    OpenAIRE

    Jo, Heeseung; Jeong, Jinkyu; Lee, Myoungho; Choi, Dong Hoon

    2013-01-01

    Recently, biological applications start to be reimplemented into the applications which exploit many cores of GPUs for better computation performance. Therefore, by providing virtualized GPUs to VMs in cloud computing environment, many biological applications will willingly move into cloud environment to enhance their computation performance and utilize infinite cloud computing resource while reducing expenses for computations. In this paper, we propose a BioCloud system architecture that ena...

  3. Exploiting Innocuous Activity for Correlating Users Across Sites

    OpenAIRE

    Goga , Oana; Lei , Howard; Parthasarathi , Sree Hari Krishnan; Friedland , Gerald; Sommer , Robin; Teixeira , Renata

    2013-01-01

    International audience; We study how potential attackers can identify accounts on different social network sites that all belong to the same user, exploiting only innocuous activity that inherently comes with posted content. We examine three specific features on Yelp, Flickr, and Twitter: the geo-location attached to a user's posts, the timestamp of posts, and the user's writing style as captured by language models. We show that among these three features the location of posts is the most powe...

  4. Assessing uncertainty and risk in exploited marine populations

    International Nuclear Information System (INIS)

    Fogarty, M.J.; Mayo, R.K.; O'Brien, L.; Serchuk, F.M.; Rosenberg, A.A.

    1996-01-01

    The assessment and management of exploited fish and invertebrate populations is subject to several types of uncertainty. This uncertainty translates into risk to the population in the development and implementation of fishery management advice. Here, we define risk as the probability that exploitation rates will exceed a threshold level where long term sustainability of the stock is threatened. We distinguish among several sources of error or uncertainty due to (a) stochasticity in demographic rates and processes, particularly in survival rates during the early fife stages; (b) measurement error resulting from sampling variation in the determination of population parameters or in model estimation; and (c) the lack of complete information on population and ecosystem dynamics. The first represents a form of aleatory uncertainty while the latter two factors represent forms of epistemic uncertainty. To illustrate these points, we evaluate the recent status of the Georges Bank cod stock in a risk assessment framework. Short term stochastic projections are made accounting for uncertainty in population size and for random variability in the number of young surviving to enter the fishery. We show that recent declines in this cod stock can be attributed to exploitation rates that have substantially exceeded sustainable levels

  5. Fishing elevates variability in the abundance of exploited species.

    Science.gov (United States)

    Hsieh, Chih-Hao; Reiss, Christian S; Hunter, John R; Beddington, John R; May, Robert M; Sugihara, George

    2006-10-19

    The separation of the effects of environmental variability from the impacts of fishing has been elusive, but is essential for sound fisheries management. We distinguish environmental effects from fishing effects by comparing the temporal variability of exploited versus unexploited fish stocks living in the same environments. Using the unique suite of 50-year-long larval fish surveys from the California Cooperative Oceanic Fisheries Investigations we analyse fishing as a treatment effect in a long-term ecological experiment. Here we present evidence from the marine environment that exploited species exhibit higher temporal variability in abundance than unexploited species. This remains true after accounting for life-history effects, abundance, ecological traits and phylogeny. The increased variability of exploited populations is probably caused by fishery-induced truncation of the age structure, which reduces the capacity of populations to buffer environmental events. Therefore, to avoid collapse, fisheries must be managed not only to sustain the total viable biomass but also to prevent the significant truncation of age structure. The double jeopardy of fishing to potentially deplete stock sizes and, more immediately, to amplify the peaks and valleys of population variability, calls for a precautionary management approach.

  6. Commercial sexual exploitation and sex trafficking of adolescents.

    Science.gov (United States)

    Chung, Richard J; English, Abigail

    2015-08-01

    This review describes the current state of commercial sexual exploitation and sex trafficking of adolescents in the United States and globally, the legal and health implications of this severe form of abuse, and the roles that pediatric and adolescent healthcare providers can play in addressing this issue. Although this form of exploitation and abuse is shrouded in secrecy, pediatric and adolescent healthcare providers are well positioned to respond when it arises. However, awareness and understanding of the issue are generally lacking among healthcare professionals, currently limiting their effectiveness in combating this problem. Although the empirical evidence base available to guide clinical care of victims of trafficking remains limited given the secretive nature of the abuse, important contributions to the multidisciplinary literature on this issue have been made in recent years, including the Institute of Medicine's landmark report in the United States. Commercial sexual exploitation and sex trafficking of adolescents represent a human rights tragedy that remains inadequately addressed. As preeminent advocates for the health and well-being of adolescents, pediatric and adolescent healthcare providers can play a crucial role in advancing efforts not only to intervene but also to prevent further victimization of vulnerable youth.

  7. Potentially exploitable supercritical geothermal resources in the ductile crust

    Science.gov (United States)

    Watanabe, Noriaki; Numakura, Tatsuya; Sakaguchi, Kiyotoshi; Saishu, Hanae; Okamoto, Atsushi; Ingebritsen, Steven E.; Tsuchiya, Noriyoshi

    2017-01-01

    The hypothesis that the brittle–ductile transition (BDT) drastically reduces permeability implies that potentially exploitable geothermal resources (permeability >10−16 m2) consisting of supercritical water could occur only in rocks with unusually high transition temperatures such as basalt. However, tensile fracturing is possible even in ductile rocks, and some permeability–depth relations proposed for the continental crust show no drastic permeability reduction at the BDT. Here we present experimental results suggesting that the BDT is not the first-order control on rock permeability, and that potentially exploitable resources may occur in rocks with much lower BDT temperatures, such as the granitic rocks that comprise the bulk of the continental crust. We find that permeability behaviour for fractured granite samples at 350–500 °C under effective confining stress is characterized by a transition from a weakly stress-dependent and reversible behaviour to a strongly stress-dependent and irreversible behaviour at a specific, temperature-dependent effective confining stress level. This transition is induced by onset of plastic normal deformation of the fracture surface (elastic–plastic transition) and, importantly, causes no ‘jump’ in the permeability. Empirical equations for this permeability behaviour suggest that potentially exploitable resources exceeding 450 °C may form at depths of 2–6 km even in the nominally ductile crust.

  8. Relativistic quantum metrology: exploiting relativity to improve quantum measurement technologies.

    Science.gov (United States)

    Ahmadi, Mehdi; Bruschi, David Edward; Sabín, Carlos; Adesso, Gerardo; Fuentes, Ivette

    2014-05-22

    We present a framework for relativistic quantum metrology that is useful for both Earth-based and space-based technologies. Quantum metrology has been so far successfully applied to design precision instruments such as clocks and sensors which outperform classical devices by exploiting quantum properties. There are advanced plans to implement these and other quantum technologies in space, for instance Space-QUEST and Space Optical Clock projects intend to implement quantum communications and quantum clocks at regimes where relativity starts to kick in. However, typical setups do not take into account the effects of relativity on quantum properties. To include and exploit these effects, we introduce techniques for the application of metrology to quantum field theory. Quantum field theory properly incorporates quantum theory and relativity, in particular, at regimes where space-based experiments take place. This framework allows for high precision estimation of parameters that appear in quantum field theory including proper times and accelerations. Indeed, the techniques can be applied to develop a novel generation of relativistic quantum technologies for gravimeters, clocks and sensors. As an example, we present a high precision device which in principle improves the state-of-the-art in quantum accelerometers by exploiting relativistic effects.

  9. Ultrasonic imaging of material flaws exploiting multipath information

    Science.gov (United States)

    Shen, Xizhong; Zhang, Yimin D.; Demirli, Ramazan; Amin, Moeness G.

    2011-05-01

    In this paper, we consider ultrasonic imaging for the visualization of flaws in a material. Ultrasonic imaging is a powerful nondestructive testing (NDT) tool which assesses material conditions via the detection, localization, and classification of flaws inside a structure. Multipath exploitations provide extended virtual array apertures and, in turn, enhance imaging capability beyond the limitation of traditional multisensor approaches. We utilize reflections of ultrasonic signals which occur when encountering different media and interior discontinuities. The waveforms observed at the physical as well as virtual sensors yield additional measurements corresponding to different aspect angles. Exploitation of multipath information addresses unique issues observed in ultrasonic imaging. (1) Utilization of physical and virtual sensors significantly extends the array aperture for image enhancement. (2) Multipath signals extend the angle of view of the narrow beamwidth of the ultrasound transducers, allowing improved visibility and array design flexibility. (3) Ultrasonic signals experience difficulty in penetrating a flaw, thus the aspect angle of the observation is limited unless access to other sides is available. The significant extension of the aperture makes it possible to yield flaw observation from multiple aspect angles. We show that data fusion of physical and virtual sensor data significantly improves the detection and localization performance. The effectiveness of the proposed multipath exploitation approach is demonstrated through experimental studies.

  10. Exploitative and hierarchical antagonism in a cooperative bacterium.

    Directory of Open Access Journals (Sweden)

    Francesca Fiegna

    2005-11-01

    Full Text Available Social organisms that cooperate with some members of their own species, such as close relatives, may fail to cooperate with other genotypes of the same species. Such noncooperation may take the form of outright antagonism or social exploitation. Myxococcus xanthus is a highly social prokaryote that cooperatively develops into spore-bearing, multicellular fruiting bodies in response to starvation. Here we have characterized the nature of social interactions among nine developmentally proficient strains of M. xanthus isolated from spatially distant locations. Strains were competed against one another in all possible pairwise combinations during starvation-induced development. In most pairings, at least one competitor exhibited strong antagonism toward its partner and a majority of mixes showed bidirectional antagonism that decreased total spore production, even to the point of driving whole populations to extinction. Differential response to mixing was the primary determinant of competitive superiority rather than the sporulation efficiencies of unmixed populations. In some competitive pairings, the dominant partner sporulated more efficiently in mixed populations than in clonal isolation. This finding represents a novel form of exploitation in bacteria carried out by socially competent genotypes and is the first documentation of social exploitation among natural bacterial isolates. Patterns of antagonistic superiority among these strains form a highly linear dominance hierarchy. At least some competition pairs construct chimeric, rather than segregated, fruiting bodies. The cooperative prokaryote M. xanthus has diverged into a large number of distinct social types that cooperate with clone-mates but exhibit intense antagonism toward distinct social types of the same species. Most lengthy migration events in nature may thus result in strong antagonism between migratory and resident populations, and this antagonism may have large effects on local

  11. Exploration and exploitation of Victorian science in Darwin's reading notebooks.

    Science.gov (United States)

    Murdock, Jaimie; Allen, Colin; DeDeo, Simon

    2017-02-01

    Search in an environment with an uncertain distribution of resources involves a trade-off between exploitation of past discoveries and further exploration. This extends to information foraging, where a knowledge-seeker shifts between reading in depth and studying new domains. To study this decision-making process, we examine the reading choices made by one of the most celebrated scientists of the modern era: Charles Darwin. From the full-text of books listed in his chronologically-organized reading journals, we generate topic models to quantify his local (text-to-text) and global (text-to-past) reading decisions using Kullback-Liebler Divergence, a cognitively-validated, information-theoretic measure of relative surprise. Rather than a pattern of surprise-minimization, corresponding to a pure exploitation strategy, Darwin's behavior shifts from early exploitation to later exploration, seeking unusually high levels of cognitive surprise relative to previous eras. These shifts, detected by an unsupervised Bayesian model, correlate with major intellectual epochs of his career as identified both by qualitative scholarship and Darwin's own self-commentary. Our methods allow us to compare his consumption of texts with their publication order. We find Darwin's consumption more exploratory than the culture's production, suggesting that underneath gradual societal changes are the explorations of individual synthesis and discovery. Our quantitative methods advance the study of cognitive search through a framework for testing interactions between individual and collective behavior and between short- and long-term consumption choices. This novel application of topic modeling to characterize individual reading complements widespread studies of collective scientific behavior. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Cyber Child Sexual Exploitation dalam Perspektif Perlindungan atas Kejahatan Siber

    Directory of Open Access Journals (Sweden)

    Go Lisanawati

    2013-04-01

    Full Text Available Perkembangan teknologi, yang diwujudkan dengan adanya inovasi berupa Internet, yang semakin pesat menempatkan semua pihak berada pada sebuah posisi yang rentan. Kerentanan tersebut dapat berupa tereksploitasinya orang menjadi korban maupun pelaku kejahatan. Teknologi menjadi pedang bermata dua dengan segala kelebihan dan eksplorasi serta eksploitasi atas kelemahan atas pemanfaatan teknologi tersebut oleh orang-orang yang tidak bertanggungjawab. Pada posisi yang sama, anak menjadi korban yang sangat potensial atas penyalahgunaan teknologi, khususnya atas eksploitasi seksual yang dapat meliputi pornografi anak, perdagangan anak, dan child sex tourism. Indonesia memang telah memiliki berbagai perangkat aturan hukum yang dipergunakan untuk memberikan perlindungan kepada anak, termasuk juga di dalamnya adalah perangkat hukum di bidang telematika. Namun demikian belum semua perangkat hukum tersebut dapat dipergunakan secara maksimal untuk mewujudkan perlindungan hukum bagi anak. The rapid development of technology through Internet nowadays has been put all parties in the vulnerable position. The vulnerable form which may appear is the possibility of the exploited parties to be victims and/or the offender of crime. Technology itself brings not only advancement but also the weaknesses which may be explored and exploited by the irresponsible people by doing such a crime. In the same position, children are potentially to be the very vulnerable victims of the misuse of the technology, especially sexual exploitation which including child pornography, child trafficking, and also child sex tourism. Indonesia is already having such kind of law to give protection to children, including also the law related to telematics matter. But not each law could maximize yet implemented to give the law protection for child.

  13. Widespread exploitation of the honeybee by early Neolithic farmers.

    Science.gov (United States)

    Roffet-Salque, Mélanie; Regert, Martine; Evershed, Richard P; Outram, Alan K; Cramp, Lucy J E; Decavallas, Orestes; Dunne, Julie; Gerbault, Pascale; Mileto, Simona; Mirabaud, Sigrid; Pääkkönen, Mirva; Smyth, Jessica; Šoberl, Lucija; Whelton, Helen L; Alday-Ruiz, Alfonso; Asplund, Henrik; Bartkowiak, Marta; Bayer-Niemeier, Eva; Belhouchet, Lotfi; Bernardini, Federico; Budja, Mihael; Cooney, Gabriel; Cubas, Miriam; Danaher, Ed M; Diniz, Mariana; Domboróczki, László; Fabbri, Cristina; González-Urquijo, Jesus E; Guilaine, Jean; Hachi, Slimane; Hartwell, Barrie N; Hofmann, Daniela; Hohle, Isabel; Ibáñez, Juan J; Karul, Necmi; Kherbouche, Farid; Kiely, Jacinta; Kotsakis, Kostas; Lueth, Friedrich; Mallory, James P; Manen, Claire; Marciniak, Arkadiusz; Maurice-Chabard, Brigitte; Mc Gonigle, Martin A; Mulazzani, Simone; Özdoğan, Mehmet; Perić, Olga S; Perić, Slaviša R; Petrasch, Jörg; Pétrequin, Anne-Marie; Pétrequin, Pierre; Poensgen, Ulrike; Pollard, C Joshua; Poplin, François; Radi, Giovanna; Stadler, Peter; Stäuble, Harald; Tasić, Nenad; Urem-Kotsou, Dushka; Vuković, Jasna B; Walsh, Fintan; Whittle, Alasdair; Wolfram, Sabine; Zapata-Peña, Lydia; Zoughlami, Jamel

    2015-11-12

    The pressures on honeybee (Apis mellifera) populations, resulting from threats by modern pesticides, parasites, predators and diseases, have raised awareness of the economic importance and critical role this insect plays in agricultural societies across the globe. However, the association of humans with A. mellifera predates post-industrial-revolution agriculture, as evidenced by the widespread presence of ancient Egyptian bee iconography dating to the Old Kingdom (approximately 2400 BC). There are also indications of Stone Age people harvesting bee products; for example, honey hunting is interpreted from rock art in a prehistoric Holocene context and a beeswax find in a pre-agriculturalist site. However, when and where the regular association of A. mellifera with agriculturalists emerged is unknown. One of the major products of A. mellifera is beeswax, which is composed of a complex suite of lipids including n-alkanes, n-alkanoic acids and fatty acyl wax esters. The composition is highly constant as it is determined genetically through the insect's biochemistry. Thus, the chemical 'fingerprint' of beeswax provides a reliable basis for detecting this commodity in organic residues preserved at archaeological sites, which we now use to trace the exploitation by humans of A. mellifera temporally and spatially. Here we present secure identifications of beeswax in lipid residues preserved in pottery vessels of Neolithic Old World farmers. The geographical range of bee product exploitation is traced in Neolithic Europe, the Near East and North Africa, providing the palaeoecological range of honeybees during prehistory. Temporally, we demonstrate that bee products were exploited continuously, and probably extensively in some regions, at least from the seventh millennium cal BC, likely fulfilling a variety of technological and cultural functions. The close association of A. mellifera with Neolithic farming communities dates to the early onset of agriculture and may provide

  14. The strv 1 microsatellite semes: Exploiting the geosynchronous transfer orbit

    Science.gov (United States)

    Blott, R. J.; Wells, N. S.; Eves, J.

    Following 3 successful years in orbit, the UK Defence Evaluation and Research Agency's two Space Technology Research Vehicle microsatellites (STRV) 1 a&b will be followed by a second mission. STRV 1 c&d are now in construction for a planned launch in 1999. The new mission, which includes 22 experimental payloads and developmental spacecraft bus technologies from European, US and Canadian military, civil and commercial sponsors, exploits the Geosynchronous Transfer Orbit (GTO) to offer an affordable, working space research tool for both government and industry. The STRV 1 programme objective is to promote the enhancement of military and civil space communications, remote sensing and navigation capabilities at reduced cost and risk. Additional aims are to help industry to achieve commercial benefit from investment in emerging technologies and to develop the synergy between government, commercial and civilian space applications. The paper explains how STRV 1 exploits the variable altitude and high radiation environment of GTO to investigate the performance of emerging technologies and techniques. This includes the accelerated life testing of components and materials, such as infra-red detectors, advanced microprocessors and solar cell technologies, and the prototyping of new techniques to improve communications and spacecraft autonomy. Experiments include implementing a secure version of the Consultative Committee for Space Data Systems (CCSDS) packet telecommand and telemetry standards, further development of the Internet-based Space Communication Protocol Standards (SCPS) and evaluating the exploitation of the Global Positioning System (GPS) in geosynchronous orbit. The new mission also builds on and extends the comprehensive environmental monitoring achieved by STRV 1 a&b.

  15. Using choice architecture to exploit a university Distinct Urban Mine.

    Science.gov (United States)

    Pierron, Xavier; Williams, Ian D; Shaw, Peter J; Cleaver, Victoria

    2017-10-01

    There are widespread concerns regarding the potential future scarcity of ferrous and non-ferrous materials. However, there are already potentially rich reserves of secondary materials via high ownership of Electrical and Electronic Equipment (EEE) in economically-developed nations. Young people are particularly high consumers of EEE, thus university students and campuses may present an opportunity to harness this potential. University Distinct Urban Mines (DUM) may be used to exemplify how potential reserves of secondary metals may be exploited, and could contribute to the transition from a linear to a circular economy. This study aimed to evaluate small household appliances (SHA) DUM from a UK university, with the objectives to identify and quantify student households' SHA ownership, WEEE recycling, stockpiling and discarding habits amongst student households, assess and evaluate the monetary potential of SHA DUM at UK level, and propose methods to exploit DUM for universities in the UK. To this purpose, a quantitative survey was undertaken to measure students' ownership and discarding behaviour with respect to SHA. The amounts of ferrous and non-ferrous materials were then estimated and converted to monetary values from secondary materials market data to appraise the SHA DUM overall value. Thirty-five per cent of SHA are discarded in the general refuse. Broken personal care appliances (PCA) tend to be discarded due to hygiene and small size factors. When in working order, SHA tend to be equally reused, recycled or stockpiled. We conclude that a total of 189 tonnes of ferrous and non-ferrous materials were available via discarding or being stockpiled at the University of Southampton. Extrapolated to UK higher education level, discarded and stockpiled SHA represent a potential worth ∼USD 11 million. To initiate DUM exploitation within Higher Education campuses, we suggest improving users' choice architecture by providing collection methods specific to broken SHA

  16. Human collective intelligence under dual exploration-exploitation dilemmas.

    Directory of Open Access Journals (Sweden)

    Wataru Toyokawa

    Full Text Available The exploration-exploitation dilemma is a recurrent adaptive problem for humans as well as non-human animals. Given a fixed time/energy budget, every individual faces a fundamental trade-off between exploring for better resources and exploiting known resources to optimize overall performance under uncertainty. Colonies of eusocial insects are known to solve this dilemma successfully via evolved coordination mechanisms that function at the collective level. For humans and other non-eusocial species, however, this dilemma operates within individuals as well as between individuals, because group members may be motivated to take excessive advantage of others' exploratory findings through social learning. Thus, even though social learning can reduce collective exploration costs, the emergence of disproportionate "information scroungers" may severely undermine its potential benefits. We investigated experimentally whether social learning opportunities might improve the performance of human participants working on a "multi-armed bandit" problem in groups, where they could learn about each other's past choice behaviors. Results showed that, even though information scroungers emerged frequently in groups, social learning opportunities reduced total group exploration time while increasing harvesting from better options, and consequentially improved collective performance. Surprisingly, enriching social information by allowing participants to observe others' evaluations of chosen options (e.g., Amazon's 5-star rating system in addition to choice-frequency information had a detrimental impact on performance compared to the simpler situation with only the choice-frequency information. These results indicate that humans groups can handle the fundamental "dual exploration-exploitation dilemmas" successfully, and that social learning about simple choice-frequencies can help produce collective intelligence.

  17. Examples of Sentinel-2A Mission Exploitation Results

    Science.gov (United States)

    Koetz, Benjamin; Hoersch, Bianca; Gascon, Ferran; Desnos, Yves-Louis; Seifert, Frank Martin; Paganini, Marc; Ramoino, Fabrizio; Arino, Olivier

    2017-04-01

    The Sentinel-2 Copernicus mission will bring significant breakthrough in the exploitation of space borne optical data. Sentinel-2 time series will transform land cover, agriculture, forestry, in-land water and costal EO applications from mapping to monitoring, from snapshot to time series data analysis, from image-based to pixel-based processing. The 5-days temporal revisiting of the Sentinel-2 satellites, when both units will be operated together, will usher us in a new era for time series analysis at high spatial resolutions (HR) of 10-20 meters. The monitoring of seasonal variations and processes in phenology and hydrology are examples of the many R&D areas to be studied. The mission's large swath and systematic acquisitions will further support unprecedented coverage at the national scale addressing information requirements of national to regional policies. Within ESA programs, such as the Data User Element (DUE), Scientific Exploitation of Operational Missions (SEOM) and Climate Change Initiative (CCI), several R&D activities are preparing the exploitation of the Sentinel-2 mission towards reliable measurements and monitoring of e.g. Essential Climate Variables and indicators for the Sustainable Development Goals. Early Sentinel-2 results will be presented related to a range of applications and scientific domains such as agricultural monitoring at national scale (DUE Sen2Agri), wetland extent and condition over African Ramsar sites (DUE GlobWetland-Africa), land cover mapping for climate change (CCI Land Cover), national land monitoring (Cadaster-Env), forest degradation (DUE ForMoSa), urban mapping (DUE EO4Urban), in-land water quality (DUE SPONGE), map of Mediterranean aquaculture (DUE SMART) and coral reef habitat mapping (SEOM S2-4Sci Coral). The above-mentioned activities are only a few examples from the very active international land imaging community building on the long-term Landsat and Spot heritage and knowledge.

  18. FSH: fast spaced seed hashing exploiting adjacent hashes.

    Science.gov (United States)

    Girotto, Samuele; Comin, Matteo; Pizzi, Cinzia

    2018-01-01

    Patterns with wildcards in specified positions, namely spaced seeds , are increasingly used instead of k -mers in many bioinformatics applications that require indexing, querying and rapid similarity search, as they can provide better sensitivity. Many of these applications require to compute the hashing of each position in the input sequences with respect to the given spaced seed, or to multiple spaced seeds. While the hashing of k -mers can be rapidly computed by exploiting the large overlap between consecutive k -mers, spaced seeds hashing is usually computed from scratch for each position in the input sequence, thus resulting in slower processing. The method proposed in this paper, fast spaced-seed hashing (FSH), exploits the similarity of the hash values of spaced seeds computed at adjacent positions in the input sequence. In our experiments we compute the hash for each positions of metagenomics reads from several datasets, with respect to different spaced seeds. We also propose a generalized version of the algorithm for the simultaneous computation of multiple spaced seeds hashing. In the experiments, our algorithm can compute the hashing values of spaced seeds with a speedup, with respect to the traditional approach, between 1.6[Formula: see text] to 5.3[Formula: see text], depending on the structure of the spaced seed. Spaced seed hashing is a routine task for several bioinformatics application. FSH allows to perform this task efficiently and raise the question of whether other hashing can be exploited to further improve the speed up. This has the potential of major impact in the field, making spaced seed applications not only accurate, but also faster and more efficient. The software FSH is freely available for academic use at: https://bitbucket.org/samu661/fsh/overview.

  19. The ESA Scientific Exploitation of Operational Missions element, first results

    Science.gov (United States)

    Desnos, Yves-Louis; Regner, Peter; Delwart, Steven; Benveniste, Jerome; Engdahl, Marcus; Mathieu, Pierre-Philippe; Gascon, Ferran; Donlon, Craig; Davidson, Malcolm; Pinnock, Simon; Foumelis, Michael; Ramoino, Fabrizio

    2016-04-01

    SEOM is a program element within the fourth period (2013-2017) of ESA's Earth Observation Envelope Programme (http://seom.esa.int/). The prime objective is to federate, support and expand the international research community that the ERS, ENVISAT and the Envelope programmes have built up over the last 25 years. It aims to further strengthen the leadership of the European Earth Observation research community by enabling them to extensively exploit future European operational EO missions. SEOM will enable the science community to address new scientific research that are opened by free and open access to data from operational EO missions. Based on community-wide recommendations for actions on key research issues, gathered through a series of international thematic workshops and scientific user consultation meetings, a work plan is established and is approved every year by ESA Members States. During 2015 SEOM, Science users consultation workshops have been organized for Sentinel1/3/5P ( Fringe, S3 Symposium and Atmospheric science respectively) , new R&D studies for scientific exploitation of the Sentinels have been launched ( S3 for Science SAR Altimetry and Ocean Color , S2 for Science,) , open-source multi-mission scientific toolboxes have been launched (in particular the SNAP/S1-2-3 Toolbox). In addition two advanced international training courses have been organized in Europe to exploit the new S1-A and S2-A data for Land and Ocean remote sensing (over 120 participants from 25 countries) as well as activities for promoting the first scientific results ( e.g. Chili Earthquake) . In addition the First EO Open Science 2.0 was organised at ESA in October 2015 with 225 participants from 31 countries bringing together young EO scientists and data scientists. During the conference precursor activities in EO Open Science and Innovation were presented, while developing a Roadmap preparing for future ESA scientific exploitation activities. Within the conference, the first

  20. Exploiting the Potential of Data Centers in the Smart Grid

    Science.gov (United States)

    Wang, Xiaoying; Zhang, Yu-An; Liu, Xiaojing; Cao, Tengfei

    As the number of cloud computing data centers grows rapidly in recent years, from the perspective of smart grid, they are really large and noticeable electric load. In this paper, we focus on the important role and the potential of data centers as controllable loads in the smart grid. We reviewed relevant research in the area of letting data centers participate in the ancillary services market and demand response programs of the grid, and further investigate the possibility of exploiting the impact of data center placement on the grid. Various opportunities and challenges are summarized, which could provide more chances for researches to explore this field.

  1. Exploitation of natural resources and conflict in Colombia

    Directory of Open Access Journals (Sweden)

    Luis Eduardo Sandoval

    2017-11-01

    Full Text Available Colombia has increasingly been specializing in the extraction of mineral and energy resources such as gold, coal, oil and ferronickel. These activities, in the context of state weakness, have engendered conflicts of different dimensions. This paper proposes an indicator of conflict related to mineral exploitation that classifies five dimensions of conflict: social, economic, cultural, political and environmental. The aggregate indicator shows that murders, displacement of Afrodescendent populations, flooding, pollution, fires, infant mortality, coca crops and sexual offenses are highly and positively correlated with the number of conflicts.

  2. Assessing Africa-wide Pangolin exploitation by scaling local data

    DEFF Research Database (Denmark)

    Ingram, Daniel J.; Coad, Lauren; Abernethy, Katharine A.

    2018-01-01

    on regional trends in exploitation of threatened species to inform conservation actions and policy. We estimate that 0.4-2.7 million pangolins are hunted annually in Central African forests. The number of pangolins hunted has increased by ∼150% and the proportion of pangolins of all vertebrates hunted...... increased from 0.04% to 1.83% over the past four decades. However, there were no trends in pangolins observed at markets, suggesting use of alternative supply chains. We found evidence that the price of giant (Smutsia gigantea) and arboreal (Phataginus sp.) pangolins in urban markets has increased...

  3. The largest renewable, easily exploitable, and economically sustainable energy resource

    Science.gov (United States)

    Abbate, Giancarlo; Saraceno, Eugenio

    2018-02-01

    Sun, the ultimate energy resource of our planet, transfers energy to the Earth at an average power of 23,000 TW. Earth surface can be regarded as a huge panel transforming solar energy into a more convenient mechanical form, the wind. Since millennia wind is recognized as an exploitable form of energy and it is common knowledge that the higher you go, the stronger the winds flow. To go high is difficult; however Bill Gates cites high wind among possible energy miracles in the near future. Public awareness of this possible miracle is still missing, but today's technology is ready for it.

  4. On the Exploitation of Sensitivity Derivatives for Improving Sampling Methods

    Science.gov (United States)

    Cao, Yanzhao; Hussaini, M. Yousuff; Zang, Thomas A.

    2003-01-01

    Many application codes, such as finite-element structural analyses and computational fluid dynamics codes, are capable of producing many sensitivity derivatives at a small fraction of the cost of the underlying analysis. This paper describes a simple variance reduction method that exploits such inexpensive sensitivity derivatives to increase the accuracy of sampling methods. Three examples, including a finite-element structural analysis of an aircraft wing, are provided that illustrate an order of magnitude improvement in accuracy for both Monte Carlo and stratified sampling schemes.

  5. Synergy in spreading processes: from exploitative to explorative foraging strategies.

    Science.gov (United States)

    Pérez-Reche, Francisco J; Ludlam, Jonathan J; Taraskin, Sergei N; Gilligan, Christopher A

    2011-05-27

    An epidemiological model which incorporates synergistic effects that allow the infectivity and/or susceptibility of hosts to be dependent on the number of infected neighbors is proposed. Constructive synergy induces an exploitative behavior which results in a rapid invasion that infects a large number of hosts. Interfering synergy leads to a slower and sparser explorative foraging strategy that traverses larger distances by infecting fewer hosts. The model can be mapped to a dynamical bond percolation with spatial correlations that affect the mechanism of spread but do not influence the critical behavior of epidemics. © 2011 American Physical Society

  6. VCSELs and silicon light sources exploiting SOI grating mirrors

    DEFF Research Database (Denmark)

    Chung, Il-Sug; Mørk, Jesper

    2012-01-01

    In this talk, novel vertical-cavity laser structure consisting of a dielectric Bragg reflector, a III-V active region, and a high-index-contrast grating made in the Si layer of a silicon-on-insulator (SOI) wafer will be presented. In the Si light source version of this laser structure, the SOI...... the Bragg reflector. Numerical simulations show that both the silicon light source and the VCSEL exploiting SOI grating mirrors have superior performances, compared to existing silicon light sources and long wavelength VCSELs. These devices are highly adequate for chip-level optical interconnects as well...

  7. Construct exploit constraint in crash analysis by bypassing canary

    Science.gov (United States)

    Huang, Ning; Huang, Shuguang; Huang, Hui; Chang, Chao

    2017-08-01

    Selective symbolic execution is a common program testing technology. Developed on the basis of it, some crash analysis systems are often used to test the fragility of the program by constructing exploit constraints, such as CRAX. From the study of crash analysis based on symbolic execution, this paper find that this technology cannot bypass the canary stack protection mechanisms. This paper makes the improvement uses the API hook in Linux. Experimental results show that the use of API hook can effectively solve the problem that crash analysis cannot bypass the canary protection.

  8. Geothermal exploitation activity by the United Nations in Ethiopia

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, H. (Geological Survey of Japan)

    1971-01-01

    The Rift Valley in Ethiopia was investigated for geothermal exploitation by the United Nations because it has Quaternary volcanoes which often indicate possible geothermal power generation. Preparations for the project are still being made, and the chemical analysis of hot springs is being conducted. The Rift Valley has high temperature springs and potential mineral deposits. The Danakil basin in Ethiopia which is included in the Northern Afar, has several active volcanoes made up of basalt deposits and has active hot springs. The East Africa Rift Valley, the Red Sea Rift Valley, and the Afar area are also areas suitable for investigation. Seven maps are included.

  9. Life Stage-specific Proteomes of Legionella pneumophila Reveal a Highly Differential Abundance of Virulence-associated Dot/Icm effectors*

    Science.gov (United States)

    Aurass, Philipp; Gerlach, Thomas; Becher, Dörte; Voigt, Birgit; Karste, Susanne; Bernhardt, Jörg; Riedel, Katharina; Hecker, Michael; Flieger, Antje

    2016-01-01

    Major differences in the transcriptional program underlying the phenotypic switch between exponential and post-exponential growth of Legionella pneumophila were formerly described characterizing important alterations in infection capacity. Additionally, a third state is known where the bacteria transform in a viable but nonculturable state under stress, such as starvation. We here describe phase-related proteomic changes in exponential phase (E), postexponential phase (PE) bacteria, and unculturable microcosms (UNC) containing viable but nonculturable state cells, and identify phase-specific proteins. We present data on different bacterial subproteomes of E and PE, such as soluble whole cell proteins, outer membrane-associated proteins, and extracellular proteins. In total, 1368 different proteins were identified, 922 were quantified and 397 showed differential abundance in E/PE. The quantified subproteomes of soluble whole cell proteins, outer membrane-associated proteins, and extracellular proteins; 841, 55, and 77 proteins, respectively, were visualized in Voronoi treemaps. 95 proteins were quantified exclusively in E, such as cell division proteins MreC, FtsN, FtsA, and ZipA; 33 exclusively in PE, such as motility-related proteins of flagellum biogenesis FlgE, FlgK, and FliA; and 9 exclusively in unculturable microcosms soluble whole cell proteins, such as hypothetical, as well as transport/binding-, and metabolism-related proteins. A high frequency of differentially abundant or phase-exclusive proteins was observed among the 91 quantified effectors of the major virulence-associated protein secretion system Dot/Icm (> 60%). 24 were E-exclusive, such as LepA/B, YlfA, MavG, Lpg2271, and 13 were PE-exclusive, such as RalF, VipD, Lem10. The growth phase-related specific abundance of a subset of Dot/Icm virulence effectors was confirmed by means of Western blotting. We therefore conclude that many effectors are predominantly abundant at either E or PE which suggests

  10. Cheating by exploitation of developmental prestalk patterning in Dictyostelium discoideum.

    Directory of Open Access Journals (Sweden)

    Anupama Khare

    2010-02-01

    Full Text Available The cooperative developmental system of the social amoeba Dictyostelium discoideum is susceptible to exploitation by cheaters-strains that make more than their fair share of spores in chimerae. Laboratory screens in Dictyostelium have shown that the genetic potential for facultative cheating is high, and field surveys have shown that cheaters are abundant in nature, but the cheating mechanisms are largely unknown. Here we describe cheater C (chtC, a strong facultative cheater mutant that cheats by affecting prestalk differentiation. The chtC gene is developmentally regulated and its mRNA becomes stalk-enriched at the end of development. chtC mutants are defective in maintaining the prestalk cell fate as some of their prestalk cells transdifferentiate into prespore cells, but that defect does not affect gross developmental morphology or sporulation efficiency. In chimerae between wild-type and chtC mutant cells, the wild-type cells preferentially give rise to prestalk cells, and the chtC mutants increase their representation in the spore mass. Mixing chtC mutants with other cell-type proportioning mutants revealed that the cheating is directly related to the prestalk-differentiation propensity of the victim. These findings illustrate that a cheater can victimize cooperative strains by exploiting an established developmental pathway.

  11. Noise-exploitation and adaptation in neuromorphic sensors

    Science.gov (United States)

    Hindo, Thamira; Chakrabartty, Shantanu

    2012-04-01

    Even though current micro-nano fabrication technology has reached integration levels where ultra-sensitive sensors can be fabricated, the sensing performance (resolution per joule) of synthetic systems are still orders of magnitude inferior to those observed in neurobiology. For example, the filiform hairs in crickets operate at fundamental limits of noise; auditory sensors in a parasitoid fly can overcome fundamental limitations to precisely localize ultra-faint acoustic signatures. Even though many of these biological marvels have served as inspiration for different types of neuromorphic sensors, the main focus these designs have been to faithfully replicate the biological functionalities, without considering the constructive role of "noise". In man-made sensors device and sensor noise are typically considered as a nuisance, where as in neurobiology "noise" has been shown to be a computational aid that enables biology to sense and operate at fundamental limits of energy efficiency and performance. In this paper, we describe some of the important noise-exploitation and adaptation principles observed in neurobiology and how they can be systematically used for designing neuromorphic sensors. Our focus will be on two types of noise-exploitation principles, namely, (a) stochastic resonance; and (b) noise-shaping, which are unified within our previously reported framework called Σ▵ learning. As a case-study, we describe the application of Σ▵ learning for the design of a miniature acoustic source localizer whose performance matches that of its biological counterpart(Ormia Ochracea).

  12. The environmental impacts of foamed concrete production and exploitation

    Science.gov (United States)

    Namsone, E.; Korjakins, A.; Sahmenko, G.; Sinka, M.

    2017-10-01

    This paper presents a study focusing on the environmental impacts of foamed concrete production and exploitation. CO2 emissions are very important factor for describing durability and sustainability of any building material and its life cycle. The building sector is one of the largest energy-consuming sectors in the world. In this study CO2 emissions are evaluated with regard to three types of energy resources (gas, coal and eco-friendly fuel). The related savings on raw materials are up to 120 t of water per 1000 t of traditionally mixed foamed concrete and up to 350 t of sand per 1000 t of foamed concrete produced with intensive mixing technology. In addition, total reduction of CO2 emissions (up to 60 t per 1000 m3 of material) and total energy saving from introduction of foamed concrete production (depending on the type of fuel) were calculated. In order to analyze the conditions of exploitation, both thermal conductivity and thickness of wall was determined. All obtained and calculated results were compared to those of the commercially produced autoclaved aerated concrete.

  13. The exploration-exploitation dilemma: a multidisciplinary framework.

    Directory of Open Access Journals (Sweden)

    Oded Berger-Tal

    Full Text Available The trade-off between the need to obtain new knowledge and the need to use that knowledge to improve performance is one of the most basic trade-offs in nature, and optimal performance usually requires some balance between exploratory and exploitative behaviors. Researchers in many disciplines have been searching for the optimal solution to this dilemma. Here we present a novel model in which the exploration strategy itself is dynamic and varies with time in order to optimize a definite goal, such as the acquisition of energy, money, or prestige. Our model produced four very distinct phases: Knowledge establishment, Knowledge accumulation, Knowledge maintenance, and Knowledge exploitation, giving rise to a multidisciplinary framework that applies equally to humans, animals, and organizations. The framework can be used to explain a multitude of phenomena in various disciplines, such as the movement of animals in novel landscapes, the most efficient resource allocation for a start-up company, or the effects of old age on knowledge acquisition in humans.

  14. The HACMS program: using formal methods to eliminate exploitable bugs.

    Science.gov (United States)

    Fisher, Kathleen; Launchbury, John; Richards, Raymond

    2017-10-13

    For decades, formal methods have offered the promise of verified software that does not have exploitable bugs. Until recently, however, it has not been possible to verify software of sufficient complexity to be useful. Recently, that situation has changed. SeL4 is an open-source operating system microkernel efficient enough to be used in a wide range of practical applications. Its designers proved it to be fully functionally correct, ensuring the absence of buffer overflows, null pointer exceptions, use-after-free errors, etc., and guaranteeing integrity and confidentiality. The CompCert Verifying C Compiler maps source C programs to provably equivalent assembly language, ensuring the absence of exploitable bugs in the compiler. A number of factors have enabled this revolution, including faster processors, increased automation, more extensive infrastructure, specialized logics and the decision to co-develop code and correctness proofs rather than verify existing artefacts. In this paper, we explore the promise and limitations of current formal-methods techniques. We discuss these issues in the context of DARPA's HACMS program, which had as its goal the creation of high-assurance software for vehicles, including quadcopters, helicopters and automobiles.This article is part of the themed issue 'Verified trustworthy software systems'. © 2017 The Authors.

  15. Exploiting Software Tool Towards Easier Use And Higher Efficiency

    Science.gov (United States)

    Lin, G. H.; Su, J. T.; Deng, Y. Y.

    2006-08-01

    In developing countries, using data based on instrument made by themselves in maximum extent is very important. It is not only related to maximizing science returns upon prophase investment -- deep accumulations in every aspects but also science output. Based on the idea, we are exploiting a software (called THDP: Tool of Huairou Data Processing). It is used for processing a series of issues, which is met necessary in processing data. This paper discusses its designed purpose, functions, method and specialities. The primary vehicle for general data interpretation is through various techniques of data visualization, techniques of interactive. In the software, we employed Object Oriented approach. It is appropriate to the vehicle. it is imperative that the approach provide not only function, but do so in as convenient a fashion as possible. As result of the software exploiting, it is not only easier to learn data processing for beginner and more convenienter to need further improvement for senior but also increase greatly efficiency in every phrases include analyse, parameter adjusting, result display. Under frame of virtual observatory, for developing countries, we should study more and newer related technologies, which can advance ability and efficiency in science research, like the software we are developing

  16. User-driven sampling strategies in image exploitation

    Science.gov (United States)

    Harvey, Neal; Porter, Reid

    2013-12-01

    Visual analytics and interactive machine learning both try to leverage the complementary strengths of humans and machines to solve complex data exploitation tasks. These fields overlap most significantly when training is involved: the visualization or machine learning tool improves over time by exploiting observations of the human-computer interaction. This paper focuses on one aspect of the human-computer interaction that we call user-driven sampling strategies. Unlike relevance feedback and active learning sampling strategies, where the computer selects which data to label at each iteration, we investigate situations where the user selects which data is to be labeled at each iteration. User-driven sampling strategies can emerge in many visual analytics applications but they have not been fully developed in machine learning. User-driven sampling strategies suggest new theoretical and practical research questions for both visualization science and machine learning. In this paper we identify and quantify the potential benefits of these strategies in a practical image analysis application. We find user-driven sampling strategies can sometimes provide significant performance gains by steering tools towards local minima that have lower error than tools trained with all of the data. In preliminary experiments we find these performance gains are particularly pronounced when the user is experienced with the tool and application domain.

  17. Exploiting GPUs in Virtual Machine for BioCloud

    Science.gov (United States)

    Jo, Heeseung; Jeong, Jinkyu; Lee, Myoungho; Choi, Dong Hoon

    2013-01-01

    Recently, biological applications start to be reimplemented into the applications which exploit many cores of GPUs for better computation performance. Therefore, by providing virtualized GPUs to VMs in cloud computing environment, many biological applications will willingly move into cloud environment to enhance their computation performance and utilize infinite cloud computing resource while reducing expenses for computations. In this paper, we propose a BioCloud system architecture that enables VMs to use GPUs in cloud environment. Because much of the previous research has focused on the sharing mechanism of GPUs among VMs, they cannot achieve enough performance for biological applications of which computation throughput is more crucial rather than sharing. The proposed system exploits the pass-through mode of PCI express (PCI-E) channel. By making each VM be able to access underlying GPUs directly, applications can show almost the same performance as when those are in native environment. In addition, our scheme multiplexes GPUs by using hot plug-in/out device features of PCI-E channel. By adding or removing GPUs in each VM in on-demand manner, VMs in the same physical host can time-share their GPUs. We implemented the proposed system using the Xen VMM and NVIDIA GPUs and showed that our prototype is highly effective for biological GPU applications in cloud environment. PMID:23710465

  18. An automated data exploitation system for airborne sensors

    Science.gov (United States)

    Chen, Hai-Wen; McGurr, Mike

    2014-06-01

    Advanced wide area persistent surveillance (WAPS) sensor systems on manned or unmanned airborne vehicles are essential for wide-area urban security monitoring in order to protect our people and our warfighter from terrorist attacks. Currently, human (imagery) analysts process huge data collections from full motion video (FMV) for data exploitation and analysis (real-time and forensic), providing slow and inaccurate results. An Automated Data Exploitation System (ADES) is urgently needed. In this paper, we present a recently developed ADES for airborne vehicles under heavy urban background clutter conditions. This system includes four processes: (1) fast image registration, stabilization, and mosaicking; (2) advanced non-linear morphological moving target detection; (3) robust multiple target (vehicles, dismounts, and human) tracking (up to 100 target tracks); and (4) moving or static target/object recognition (super-resolution). Test results with real FMV data indicate that our ADES can reliably detect, track, and recognize multiple vehicles under heavy urban background clutters. Furthermore, our example shows that ADES as a baseline platform can provide capability for vehicle abnormal behavior detection to help imagery analysts quickly trace down potential threats and crimes.

  19. Exploitation of Clustering Techniques in Transactional Healthcare Data

    Directory of Open Access Journals (Sweden)

    Naeem Ahmad Mahoto

    2014-03-01

    Full Text Available Healthcare service centres equipped with electronic health systems have improved their resources as well as treatment processes. The dynamic nature of healthcare data of each individual makes it complex and difficult for physicians to manually mediate them; therefore, automatic techniques are essential to manage the quality and standardization of treatment procedures. Exploratory data analysis, patternanalysis and grouping of data is managed using clustering techniques, which work as an unsupervised classification. A number of healthcare applications are developed that use several data mining techniques for classification, clustering and extracting useful information from healthcare data. The challenging issue in this domain is to select adequate data mining algorithm for optimal results. This paper exploits three different clustering algorithms: DBSCAN (Density-Based Clustering, agglomerative hierarchical and k-means in real transactional healthcare data of diabetic patients (taken as case study to analyse their performance in large and dispersed healthcare data. The best solution of cluster sets among the exploited algorithms is evaluated using clustering quality indexes and is selected to identify the possible subgroups of patients having similar treatment patterns

  20. Exploiting similarity in turbulent shear flows for turbulence modeling

    Science.gov (United States)

    Robinson, David F.; Harris, Julius E.; Hassan, H. A.

    1992-01-01

    It is well known that current k-epsilon models cannot predict the flow over a flat plate and its wake. In an effort to address this issue and other issues associated with turbulence closure, a new approach for turbulence modeling is proposed which exploits similarities in the flow field. Thus, if we consider the flow over a flat plate and its wake, then in addition to taking advantage of the log-law region, we can exploit the fact that the flow becomes self-similar in the far wake. This latter behavior makes it possible to cast the governing equations as a set of total differential equations. Solutions of this set and comparison with measured shear stress and velocity profiles yields the desired set of model constants. Such a set is, in general, different from other sets of model constants. The rational for such an approach is that if we can correctly model the flow over a flat plate and its far wake, then we can have a better chance of predicting the behavior in between. It is to be noted that the approach does not appeal, in any way, to the decay of homogeneous turbulence. This is because the asymptotic behavior of the flow under consideration is not representative of the decay of homogeneous turbulence.

  1. JPEG2000-coded image error concealment exploiting convex sets projections.

    Science.gov (United States)

    Atzori, Luigi; Ginesu, Giaime; Raccis, Alessio

    2005-04-01

    Transmission errors in JPEG2000 can be grouped into three main classes, depending on the affected area: LL, high frequencies at the lower decomposition levels, and high frequencies at the higher decomposition levels. The first type of errors are the most annoying but can be concealed exploiting the signal spatial correlation like in a number of techniques proposed in the past; the second are less annoying but more difficult to address; the latter are often imperceptible. In this paper, we address the problem of concealing the second class or errors when high bit-planes are damaged by proposing a new approach based on the theory of projections onto convex sets. Accordingly, the error effects are masked by iteratively applying two procedures: low-pass (LP) filtering in the spatial domain and restoration of the uncorrupted wavelet coefficients in the transform domain. It has been observed that a uniform LP filtering brought to some undesired side effects that negatively compensated the advantages. This problem has been overcome by applying an adaptive solution, which exploits an edge map to choose the optimal filter mask size. Simulation results demonstrated the efficiency of the proposed approach.

  2. Exploiting similarity in turbulent shear flows for turbulence modeling

    Science.gov (United States)

    Robinson, David F.; Harris, Julius E.; Hassan, H. A.

    1992-12-01

    It is well known that current k-epsilon models cannot predict the flow over a flat plate and its wake. In an effort to address this issue and other issues associated with turbulence closure, a new approach for turbulence modeling is proposed which exploits similarities in the flow field. Thus, if we consider the flow over a flat plate and its wake, then in addition to taking advantage of the log-law region, we can exploit the fact that the flow becomes self-similar in the far wake. This latter behavior makes it possible to cast the governing equations as a set of total differential equations. Solutions of this set and comparison with measured shear stress and velocity profiles yields the desired set of model constants. Such a set is, in general, different from other sets of model constants. The rational for such an approach is that if we can correctly model the flow over a flat plate and its far wake, then we can have a better chance of predicting the behavior in between. It is to be noted that the approach does not appeal, in any way, to the decay of homogeneous turbulence. This is because the asymptotic behavior of the flow under consideration is not representative of the decay of homogeneous turbulence.

  3. Exploitation of puddles for breakthroughs in claustrum research

    Directory of Open Access Journals (Sweden)

    John Irwin Johnson

    2014-05-01

    Full Text Available Since its first identification as a thin strip of gray matter enclosed between stretches of neighboring fiber bundles, the claustrum has been considered impossible to study by many modern techniques that need a certain roominess of tissue for their application. The claustrum was known as the front wall, vormauren in German from 1822, and is still called avant-mur in French. We here propose a means for breaking into and through this wall, by utilizing the instances where the claustral tissue itself has broken free into more spacious dimensions. This has occurred several times in the evolution of modern mammals, and all that needs be done is to exploit these natural expansions in order to take advantage of a great panoply of technological advances now at our disposal. So here we review the kinds of breakout puddles that await productive exploitation, to bring our knowledge of structure and function up to the level enjoyed for other more accessible regions of the brain..

  4. Activity-based exploitation of Full Motion Video (FMV)

    Science.gov (United States)

    Kant, Shashi

    2012-06-01

    Video has been a game-changer in how US forces are able to find, track and defeat its adversaries. With millions of minutes of video being generated from an increasing number of sensor platforms, the DOD has stated that the rapid increase in video is overwhelming their analysts. The manpower required to view and garner useable information from the flood of video is unaffordable, especially in light of current fiscal restraints. "Search" within full-motion video has traditionally relied on human tagging of content, and video metadata, to provision filtering and locate segments of interest, in the context of analyst query. Our approach utilizes a novel machine-vision based approach to index FMV, using object recognition & tracking, events and activities detection. This approach enables FMV exploitation in real-time, as well as a forensic look-back within archives. This approach can help get the most information out of video sensor collection, help focus the attention of overburdened analysts form connections in activity over time and conserve national fiscal resources in exploiting FMV.

  5. Exploiting GPUs in Virtual Machine for BioCloud

    Directory of Open Access Journals (Sweden)

    Heeseung Jo

    2013-01-01

    Full Text Available Recently, biological applications start to be reimplemented into the applications which exploit many cores of GPUs for better computation performance. Therefore, by providing virtualized GPUs to VMs in cloud computing environment, many biological applications will willingly move into cloud environment to enhance their computation performance and utilize infinite cloud computing resource while reducing expenses for computations. In this paper, we propose a BioCloud system architecture that enables VMs to use GPUs in cloud environment. Because much of the previous research has focused on the sharing mechanism of GPUs among VMs, they cannot achieve enough performance for biological applications of which computation throughput is more crucial rather than sharing. The proposed system exploits the pass-through mode of PCI express (PCI-E channel. By making each VM be able to access underlying GPUs directly, applications can show almost the same performance as when those are in native environment. In addition, our scheme multiplexes GPUs by using hot plug-in/out device features of PCI-E channel. By adding or removing GPUs in each VM in on-demand manner, VMs in the same physical host can time-share their GPUs. We implemented the proposed system using the Xen VMM and NVIDIA GPUs and showed that our prototype is highly effective for biological GPU applications in cloud environment.

  6. Exploiting first-class arrays in Fortran for accelerator programming

    International Nuclear Information System (INIS)

    Rasmussen, Craig E.; Weseloh, Wayne N.; Robey, Robert W.; Sottile, Matthew J.; Quinlan, Daniel; Overbey, Jeffrey

    2010-01-01

    Emerging architectures for high performance computing often are well suited to a data parallel programming model. This paper presents a simple programming methodology based on existing languages and compiler tools that allows programmers to take advantage of these systems. We will work with the array features of Fortran 90 to show how this infrequently exploited, standardized language feature is easily transformed to lower level accelerator code. Our transformations are based on a mapping from Fortran 90 to C++ code with OpenCL extensions. The sheer complexity of programming for clusters of many or multi-core processors with tens of millions threads of execution make the simplicity of the data parallel model attractive. Furthermore, the increasing complexity of todays applications (especially when convolved with the increasing complexity of the hardware) and the need for portability across hardware architectures make a higher-level and simpler programming model like data parallel attractive. The goal of this work has been to exploit source-to-source transformations that allow programmers to develop and maintain programs at a high-level of abstraction, without coding to a specific hardware architecture. Furthermore these transformations allow multiple hardware architectures to be targeted without changing the high-level source. It also removes the necessity for application programmers to understand details of the accelerator architecture or to know OpenCL.

  7. Human trafficking for labour exploitation:
    Interpreting the crime

    Directory of Open Access Journals (Sweden)

    Jill E.B. Coster van Voorhout

    2007-12-01

    Full Text Available The definition of human trafficking for labour exploitation, as follows from the European Council Framework Decision, proves to be unclear. Literal interpretation does not suffice, because it does not clarify all elements of what is deemed to be criminal behaviour, and hermeneutical interpretation also falls short discouraging the aim of this legislation, namely harmonisation. Hence, another solution is required. This article does so by firstly challenging assumptions about human trafficking for labour exploitation that are generally pertinent, but nonetheless untrue. This accurate appraisal of the crime’s nature is followed by a synopsis of national legislation and adjudication in three Member States, so as to also focus on these actualities regarding the crime that are commonly not conceived. This article examines two countries that have implemented the Framework Decision, namely Belgium and the Netherlands, and one that has not yet done so, the United Kingdom. Thereafter remaining unexplained elements of the Framework Decision’s definition are interpreted with use of international, pan-European and European legislation and adjudication. Based upon all this, a suggested interpretation of the Framework Decision’s definition is provided so as to overcome all identified difficulties with it.

  8. Film-induced, steps for a Real Exploitation in Europe

    Directory of Open Access Journals (Sweden)

    Francesco di Cesare

    2015-03-01

    Full Text Available One of the possible ways to enhance Europe visibility, its entirety rather than a set of destinations, is implementing cooperation between the Member States especially in creating and developing trans-border thematic tourist products and experiences. One of them could be the film-induced tourism. In looking back over the past two cycles of European programming it is possible to find some examples, described in the article, in which the theme of audiovisual productions in their shooting phase in European locations has been the subject of EU attention.This article refers to some previous research results reminding how movie-induced tourism seems to be used just through sporadic attempts and therefore not developed and exploited in a strategic way. Whether from demand-side is clear what potential is inherent in the relationship between movie and tourism, on the supply side there is still much to do.As the current EC funding period (2014-2020 is favouring, at least in the first calls for proposal that came out, SMEs projects and being aware of the apparent lack of such activities developed by private businesses, the article explores new opportunities to be gathered suggesting a new exploitation path.

  9. Cheating by Exploitation of Developmental Prestalk Patterning in Dictyostelium discoideum

    Science.gov (United States)

    Khare, Anupama; Shaulsky, Gad

    2010-01-01

    The cooperative developmental system of the social amoeba Dictyostelium discoideum is susceptible to exploitation by cheaters—strains that make more than their fair share of spores in chimerae. Laboratory screens in Dictyostelium have shown that the genetic potential for facultative cheating is high, and field surveys have shown that cheaters are abundant in nature, but the cheating mechanisms are largely unknown. Here we describe cheater C (chtC), a strong facultative cheater mutant that cheats by affecting prestalk differentiation. The chtC gene is developmentally regulated and its mRNA becomes stalk-enriched at the end of development. chtC mutants are defective in maintaining the prestalk cell fate as some of their prestalk cells transdifferentiate into prespore cells, but that defect does not affect gross developmental morphology or sporulation efficiency. In chimerae between wild-type and chtC mutant cells, the wild-type cells preferentially give rise to prestalk cells, and the chtC mutants increase their representation in the spore mass. Mixing chtC mutants with other cell-type proportioning mutants revealed that the cheating is directly related to the prestalk-differentiation propensity of the victim. These findings illustrate that a cheater can victimize cooperative strains by exploiting an established developmental pathway. PMID:20195510

  10. Indirect evolution of social fitness inequalities and facultative social exploitation.

    Science.gov (United States)

    Nair, Ramith R; Fiegna, Francesca; Velicer, Gregory J

    2018-03-28

    Microbial genotypes with similarly high proficiency at a cooperative behaviour in genetically pure groups often exhibit fitness inequalities caused by social interaction in mixed groups. Winning competitors in this scenario have been referred to as 'cheaters' in some studies. Such interaction-specific fitness inequalities, as well as social exploitation (in which interaction between genotypes increases absolute fitness), might evolve due to selection for competitiveness at the focal behaviour or might arise non-adaptively due to pleiotropy, hitchhiking or genetic drift. The bacterium Myxococcus xanthus sporulates during cooperative development of multicellular fruiting bodies. Using M. xanthus lineages that underwent experimental evolution in allopatry without selection on sporulation, we demonstrate that interaction-specific fitness inequalities and facultative social exploitation during development readily evolved indirectly among descendant lineages. Fitness inequalities between evolved genotypes were not caused by divergence in developmental speed, as faster-developing strains were not over-represented among competition winners. In competitions between ancestors and several evolved strains, all evolved genotypes produced more spores than the ancestors, including losers of evolved-versus-evolved competitions, indicating that adaptation in non-developmental contexts pleiotropically increased competitiveness for spore production. Overall, our results suggest that fitness inequalities caused by social interaction during cooperative processes may often evolve non-adaptively in natural populations. © 2018 The Authors.

  11. Gas exploitation and gas conversion; Gassutnyttelse og gasskonvertering

    Energy Technology Data Exchange (ETDEWEB)

    Laading, Gjert

    1998-07-01

    This presentation deals with some of the challenges and possibilities connected with ''stranded'' gas. These are offshore gas reserves, especially associated gas, that is not connected with the market and that cannot be piped onshore, and where reinjection is not profitable, and where flaring off is not an option. There is increasing interest all over the world to find economical and environmentally friendly solutions to this problem. A good solution will render such fields economically developable and will to a high degree increase the total volume of the world's exploitable gas reserves. Since synthesis gas is a dominating cost element in most chemical conversion processes for gas, the synthesis gases are discussed in some detail. There is also a discussion of the conversion of the gas to Methanol, Synthetic oil (Syncrude and Synfuels) and to DME (Di-methyl-ether). Two methods for gas transport from the field are discussed; LNG on floating production storage and off loading (FPSO), and Gas hydrates. Principles, limitations and conditions for placing those processes on a FPSO. Finally, the presentation discusses the most important economic factors related to the exploitation of offshore gas, and suggests some possibilities for future development.11 figs.

  12. Exploiting the Dynamics of Soft Materials for Machine Learning.

    Science.gov (United States)

    Nakajima, Kohei; Hauser, Helmut; Li, Tao; Pfeifer, Rolf

    2018-06-01

    Soft materials are increasingly utilized for various purposes in many engineering applications. These materials have been shown to perform a number of functions that were previously difficult to implement using rigid materials. Here, we argue that the diverse dynamics generated by actuating soft materials can be effectively used for machine learning purposes. This is demonstrated using a soft silicone arm through a technique of multiplexing, which enables the rich transient dynamics of the soft materials to be fully exploited as a computational resource. The computational performance of the soft silicone arm is examined through two standard benchmark tasks. Results show that the soft arm compares well to or even outperforms conventional machine learning techniques under multiple conditions. We then demonstrate that this system can be used for the sensory time series prediction problem for the soft arm itself, which suggests its immediate applicability to a real-world machine learning problem. Our approach, on the one hand, represents a radical departure from traditional computational methods, whereas on the other hand, it fits nicely into a more general perspective of computation by way of exploiting the properties of physical materials in the real world.

  13. Exploitation of the in-seam miner and operational experience

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, W I.S.; Morris, A H

    1977-12-01

    The In-seam Miner started as an investigatory project at MRDE in 1969. Since that time it has passed through the classic development stages of design of prototype, surface trials, underground trials, modification, production of more machines, assessment of experience and then wider exploitation. At the present time well over 100 machines have been supplied to the National Coal Board. The original machine was hydraulically driven and all but five of the machines supplied to date are of this type. The variety of applications that the machine has found in the mining industry has caused derivative development to embrace machines of length varying from 12-ft centers to 44-ft centers, to work in seams ranging from 40 in. up to 68 in. The range of applications has included face drivages, stablehole operations, in-seam retreat roadways and dirt-absorbing headings. Five electrically driven machines are now coming onto the market and experience with them, though limited, is very encouraging. The paper concentrates on two major aspects of the overall development process: first, the management of exploitation; and second, some operational experience of the In-seam Miner in South Midlands area.

  14. Self-report measure of financial exploitation of older adults.

    Science.gov (United States)

    Conrad, Kendon J; Iris, Madelyn; Ridings, John W; Langley, Kate; Wilber, Kathleen H

    2010-12-01

    this study was designed to improve the measurement of financial exploitation (FE) by testing psychometric properties of the older adult financial exploitation measure (OAFEM), a client self-report instrument. rasch item response theory and traditional validation approaches were used. Questionnaires were administered by 22 adult protective services investigators from 7 agencies in Illinois to 227 substantiated abuse clients. Analyses included tests for dimensionality, model fit, and additional construct validation. Results from the OAFEM were also compared with the substantiation decision of abuse and with investigators' assessments of FE using a staff report version. Hypotheses were generated to test hypothesized relationships. the OAFEM, including the original 79-, 54-, and 30-item measures, met stringent Rasch analysis fit and unidimensionality criteria and had high internal consistency and item reliability. The validation results were supportive, while leading to reconsideration of aspects of the hypothesized theoretical hierarchy. Thresholds were suggested to demonstrate levels of severity. the measure is now available to aid in the assessment of FE of older adults by both clinicians and researchers. Theoretical refinements developed using the empirically generated item hierarchy may help to improve assessment and intervention.

  15. Exploiting GPUs in virtual machine for BioCloud.

    Science.gov (United States)

    Jo, Heeseung; Jeong, Jinkyu; Lee, Myoungho; Choi, Dong Hoon

    2013-01-01

    Recently, biological applications start to be reimplemented into the applications which exploit many cores of GPUs for better computation performance. Therefore, by providing virtualized GPUs to VMs in cloud computing environment, many biological applications will willingly move into cloud environment to enhance their computation performance and utilize infinite cloud computing resource while reducing expenses for computations. In this paper, we propose a BioCloud system architecture that enables VMs to use GPUs in cloud environment. Because much of the previous research has focused on the sharing mechanism of GPUs among VMs, they cannot achieve enough performance for biological applications of which computation throughput is more crucial rather than sharing. The proposed system exploits the pass-through mode of PCI express (PCI-E) channel. By making each VM be able to access underlying GPUs directly, applications can show almost the same performance as when those are in native environment. In addition, our scheme multiplexes GPUs by using hot plug-in/out device features of PCI-E channel. By adding or removing GPUs in each VM in on-demand manner, VMs in the same physical host can time-share their GPUs. We implemented the proposed system using the Xen VMM and NVIDIA GPUs and showed that our prototype is highly effective for biological GPU applications in cloud environment.

  16. The HACMS program: using formal methods to eliminate exploitable bugs

    Science.gov (United States)

    Launchbury, John; Richards, Raymond

    2017-01-01

    For decades, formal methods have offered the promise of verified software that does not have exploitable bugs. Until recently, however, it has not been possible to verify software of sufficient complexity to be useful. Recently, that situation has changed. SeL4 is an open-source operating system microkernel efficient enough to be used in a wide range of practical applications. Its designers proved it to be fully functionally correct, ensuring the absence of buffer overflows, null pointer exceptions, use-after-free errors, etc., and guaranteeing integrity and confidentiality. The CompCert Verifying C Compiler maps source C programs to provably equivalent assembly language, ensuring the absence of exploitable bugs in the compiler. A number of factors have enabled this revolution, including faster processors, increased automation, more extensive infrastructure, specialized logics and the decision to co-develop code and correctness proofs rather than verify existing artefacts. In this paper, we explore the promise and limitations of current formal-methods techniques. We discuss these issues in the context of DARPA’s HACMS program, which had as its goal the creation of high-assurance software for vehicles, including quadcopters, helicopters and automobiles. This article is part of the themed issue ‘Verified trustworthy software systems’. PMID:28871050

  17. The Potential Socio-economic Impacts of Gas Hydrate Exploitation

    Science.gov (United States)

    Riley, David; Schaafsma, Marije; Marin-Moreno, Héctor; Minshull, Tim A.

    2017-04-01

    Gas hydrate has garnered significant interest as a possible clean fossil fuel resource, especially in countries with limited energy supplies. Whilst the sector is still in its infancy, there has been escalating development towards commercial production. To the best of our knowledge it appears that, despite its potential, existing analyses of the social and economic impacts of hydrate exploitation have been very limited. Before any viable commercial production commences, the potential impacts across society must be considered. It is likely that such impact assessments will become a legislative requirement for hydrate exploitation, similar to their requirement in conventional oil and gas projects. Social impact analysis should guide hydrate development to have the highest possible net benefits to the human and natural environment. Without active commercial hydrate operations, potential socio-economic impacts can only be inferred from other fossil fuel resource focused communities, including those directly or indirectly affected by the oil and gas industry either in the vicinity of the well or further afield. This review attempts to highlight potential impacts by synthesising current literature, focusing on social impacts at the extraction stage of operation, over time. Using a DPSIR (Driving forces; Pressures; States; Impacts; Responses) framework, we focus on impacts upon: health and wellbeing, land use and access, services and infrastructure, population, employment opportunities, income and lifestyles. Human populations directly or indirectly related with fossil fuel extraction activities often show boom and bust dynamics, and so any impacts may be finite or change temporally. Therefore potential impacts have to be reassessed throughout the lifetime of the exploitation. Our review shows there are a wide range of possible positive and negative socio-economic impacts from hydrate development. Exploitation can bring jobs and infrastructure to remote areas, although

  18. Ambidextrous Organizations: A Multiple-Level Study of Absorptive Capacity, Exploratory and Exploitative Innovation and Performance

    NARCIS (Netherlands)

    J.J.P. Jansen (Justin)

    2005-01-01

    textabstractBalancing and synchronizing exploration and exploitation is fundamental to the competitive success of firms in dynamic environments. Despite the importance of reconciling exploration and exploitation within organizations, however, relatively little empirical research has examined this

  19. Water Exploitation and Its Outcomes Caused by Capitalism as Reflected on Gore Verbinski's Rango Movie

    OpenAIRE

    SETIAWAN, DANIEL NUGRAHA

    2014-01-01

    Nugraha Setiawan, Daniel. 2014. Water Exploitation and Its Outcome Caused byCapitalism as Reflected on Gore Verbinski's Rango Movie. Study Program ofEnglish, Universitas Brawijaya.Supervisor: Yusri Fajar, Co-supervisor: Melania Shinta Harendika.Keywords: water exploitation, environment, capitalism, Rango movie. Water exploitation threats ecosystem and causes a great damage to environment. One of the causes of the water exploitation is capitalism. The movie entitled Rango reveals some causes a...

  20. Child Sexual Abuse and Exploitation: Guest Editor’s Introduction

    Directory of Open Access Journals (Sweden)

    Michael Salter

    2015-07-01

    Full Text Available One of the most unnerving aspects of child sexual abuse is that it is constantly manifesting in unexpected ways. The current Royal Commission into Institutional Responses to Child Sexual Abuse has collected testimony of abuse in churches, schools, out-of-home care, hospitals and religious communities, demonstrating the breadth of institutional arrangements whose structures and cultures have facilitated child sexual abuse. Cases of serious and prolonged sexual abuse in family contexts have been excluded from the terms of reference of the Royal Commission but nonetheless continue to surface in media reports. In 2013, twelve children were permanently removed from an extended family living in rural NSW in what has been described as one of the worst cases of child abuse in Australia, involving intergenerational incest going back at least three generations (Auebach 2014. Another recent high-profile case involved the use of the Internet to facilitate the sexual exploitation of an adopted child by his parents in Queensland (Ralston 2013. These cases challenge the received wisdom that child sexual abuse is characterised by the victimisation of one child by one opportunistic offender. Such incidents suggest instead that child sexual abuse takes varied and systemic forms, and can operate to perpetuate and entrench toxic cultures and power structures.   This special issue on Child Sexual Abuse and Exploitation is a timely contribution to ongoing efforts to understand the multiplicity of child sexual abuse. It is an interdisciplinary collection of insights drawn from criminology, sociology, psychiatry, psychology and psychoanalysis, and includes papers from academic researchers alongside academic practitioners whose writing is grounded in their work with affected individuals and communities. A key aim of the special issue is to contextualise the diversity of child sexual abuse socially, politically and historically, recognising the dynamic and iterative

  1. Shale Gas Exploration and Exploitation Induced Risks - SHEER

    Science.gov (United States)

    Capuano, Paolo; Orlecka-Sikora, Beata; Lasocki, Stanislaw; Cesca, Simone; Gunning, Andrew; jaroslawsky, Janusz; Garcia-Aristizabal, Alexander; Westwood, Rachel; Gasparini, Paolo

    2017-04-01

    Shale gas operations may affect the quality of air, water and landscapes; furthermore, it can induce seismic activity, with the possible impacts on the surrounding infrastructure. The SHEER project aims at setting up a probabilistic methodology to assess and mitigate the short and the long term environmental risks connected to the exploration and exploitation of shale gas. In particular we are investigating risks associated with groundwater contamination, air pollution and induced seismicity. A shale gas test site located in Poland (Wysin) has been monitored before, during and after the fracking operations with the aim of assessing environmental risks connected with groundwater contamination, air pollution and earthquakes induced by fracking and injection of waste water. The severity of each of these hazards depends strongly on the unexpected enhanced permeability pattern, which may develop as an unwanted by-product of the fracking processes and may become pathway for gas and fluid migration towards underground water reservoirs or the surface. The project is devoted to monitor and understand how far this enhanced permeability pattern develops both in space and time. The considered hazards may be at least partially inter-related as they all depend on this enhanced permeability pattern. Therefore they are being approached from a multi-hazard, multi parameter perspective. We expect to develop methodologies and procedures to track and model fracture evolution around shale gas exploitation sites and a robust statistically based, multi-parameter methodology to assess environmental impacts and risks across the operational lifecycle of shale gas. The developed methodologies are going to be applied and tested on a comprehensive database consisting of seismicity, changes of the quality of ground-waters and air, ground deformations, and operational data collected from the ongoing monitoring episode (Wysin) and past episodes: Lubocino (Poland), Preese Hall (UK), Oklahoma (USA

  2. The exploitation of living resources in the Dutch Wadden Sea : a historical overview

    NARCIS (Netherlands)

    Wolff, W J

    An overview, based on written sources and personal observations, is presented of exploitation of living resources in and around the Dutch Wadden Sea during the past few centuries. It is concluded that before about 1900 exploitation was almost unrestricted. Exploitation of plants has been documented

  3. 25 CFR 20.516 - How are child abuse, neglect or exploitation cases to be handled?

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false How are child abuse, neglect or exploitation cases to be... FINANCIAL ASSISTANCE AND SOCIAL SERVICES PROGRAMS Child Assistance Foster Care § 20.516 How are child abuse, neglect or exploitation cases to be handled? Reported child abuse, neglect or exploitation cases and the...

  4. The strategic and economic value of exploiting heavy crude

    International Nuclear Information System (INIS)

    Saniere, A.

    2003-01-01

    Non-conventional oil, and particularly heavy crude varieties, will play an increasingly important role in meeting growing global energy requirements by 2030 and beyond. These heavy oils currently account for high volumes in certain areas but their proportion of global oil production remains modest for the moment, This should significantly change with the completion of several projects currently underway in Canada and Venezuela. Indeed, the technological innovations occurring over recent years have allowed for a considerable reduction in exploitation costs for these crude varieties and improved economic profitability conditions for the projects. The geographical location of resources (which are independent of the Middle East) and the fact that they are not subject to OPEC quotas also make these crude varieties particularly attractive. (authors)

  5. Exploiting peer group concept for adaptive and highly available services

    CERN Document Server

    Jan, M A; Fraz, M M; Ali, A; Ali, Arshad; Fraz, Mohammad Moazam; Jan, Muhammad Asif; Zahid, Fahd Ali

    2003-01-01

    This paper presents a prototype for redundant, highly available and fault tolerant peer to peer framework for data management. Peer to peer computing is gaining importance due to its flexible organization, lack of central authority, distribution of functionality to participating nodes and ability to utilize unused computational resources. Emergence of GRID computing has provided much needed infrastructure and administrative domain for peer to peer computing. The components of this framework exploit peer group concept to scope service and information search, arrange services and information in a coherent manner, provide selective redundancy and ensure availability in face of failure and high load conditions. A prototype system has been implemented using JXTA peer to peer technology and XML is used for service description and interfaces, allowing peers to communicate with services implemented in various platforms including web services and JINI services. It utilizes code mobility to achieve role interchange amo...

  6. Sustained Administration of Hormones Exploiting Nanoconfined Diffusion through Nanochannel Membranes

    Directory of Open Access Journals (Sweden)

    Thomas Geninatti

    2015-08-01

    Full Text Available Implantable devices may provide a superior means for hormone delivery through maintaining serum levels within target therapeutic windows. Zero-order administration has been shown to reach an equilibrium with metabolic clearance, resulting in a constant serum concentration and bioavailability of released hormones. By exploiting surface-to-molecule interaction within nanochannel membranes, it is possible to achieve a long-term, constant diffusive release of agents from implantable reservoirs. In this study, we sought to demonstrate the controlled release of model hormones from a novel nanochannel system. We investigated the delivery of hormones through our nanochannel membrane over a period of 40 days. Levothyroxine, osteocalcin and testosterone were selected as representative hormones based on their different molecular properties and structures. The release mechanisms and transport behaviors of these hormones within 3, 5 and 40 nm channels were characterized. Results further supported the suitability of the nanochannels for sustained administration from implantable platforms.

  7. Commercial Sexual Exploitation of Children and State Child Welfare Systems.

    Science.gov (United States)

    Bounds, Dawn; Julion, Wrenetha A; Delaney, Kathleen R

    2015-01-01

    In several states, commercial sexual exploitation of children (CSEC) is now a reportable child abuse offense. Illinois has taken the lead in tackling the issue and the Illinois experience illuminates valuable lessons. This article delineates the protection, practice, and policy implications that evolve when CSEC falls under a state child welfare system. The specific aims are to (a) discuss CSEC, its victims, risks, harms, and challenges inherent in providing effective care; (b) use Illinois as an exemplar to explicate the consequences and implementation challenges of establishing a state reporting system that frames CSEC as a child welfare issue; (c) recommend strategies for developing effective state reporting models, and (d) demonstrate how nurses are well poised to advocate for victims of human trafficking on both state and national levels. Recommendations for improving the identification of CSEC victims and overcoming challenges to state implementation are offered. © The Author(s) 2015.

  8. Shale gas, Poland pioneer of exploitation in Europe

    International Nuclear Information System (INIS)

    Rybicka, Urszula; Khalatbari, Azar; Schneider, Frederic; Nabrdalik, Maciek

    2012-01-01

    This article presents an installation built by a Polish company to perform drillings in the search for shale gas pockets from which gas would be extracted by hydraulic fracturing. Some technical characteristics of the installation and process are evoked. The article outlines the confidence the population now has gained in this installation. However and despite the fact that the region possesses important underground water reserves, water consumption is reported to be too high with respect to farmer needs. Besides, some farmers have had a compulsory purchase order made on their land and could afford to buy new lands. However, in some other places, the population did not accept the arrival of the multinational company Chevron. In parallel, a brief overview of shale gas exploitation projects or status in other European countries is given

  9. Exploiting CRISPR/Cas: Interference Mechanisms and Applications

    Directory of Open Access Journals (Sweden)

    André Plagens

    2013-07-01

    Full Text Available The discovery of biological concepts can often provide a framework for the development of novel molecular tools, which can help us to further understand and manipulate life. One recent example is the elucidation of the prokaryotic adaptive immune system, clustered regularly interspaced short palindromic repeats (CRISPR/CRISPR-associated (Cas that protects bacteria and archaea against viruses or conjugative plasmids. The immunity is based on small RNA molecules that are incorporated into versatile multi-domain proteins or protein complexes and specifically target viral nucleic acids via base complementarity. CRISPR/Cas interference machines are utilized to develop novel genome editing tools for different organisms. Here, we will review the latest progress in the elucidation and application of prokaryotic CRISPR/Cas systems and discuss possible future approaches to exploit the potential of these interference machineries.

  10. Exploitation of wind energy and its potential in Czechoslovakia

    International Nuclear Information System (INIS)

    Rychetnik, V.

    1990-01-01

    Examples from over the world are shown to demonstrate the potential of wind energy in power generation. The basic types of wind motors and the installed capacities are given. In Czechoslovakia the wind conditions are rather complex. Wind energy can be economically exploited at sites where the mean wind velocity at 10 m above the ground exceeds 4 m/s. This can cover about 2% of annual power generation in Czechoslovakia. The amount of electricity generated and its cost are estimated. The investment into a wind power plant would pay back in several years. The use of small wind power plants to supply, e.g., individual houses will be of limited importance. (M.D.). 4 figs., 8 refs

  11. Microbial biosurfactants: challenges and opportunities for future exploitation.

    Science.gov (United States)

    Marchant, Roger; Banat, Ibrahim M

    2012-11-01

    The drive for industrial sustainability has pushed biosurfactants to the top of the agenda of many companies. Biosurfactants offer the possibility of replacing chemical surfactants, produced from nonrenewable resources, with alternatives produced from cheap renewable feedstocks. Biosurfactants are also attractive because they are less damaging to the environment yet are robust enough for industrial use. The most promising biosurfactants at the present time are the glycolipids, sophorolipids produced by Candida yeasts, mannosylerythritol lipids (MELs) produced by Pseudozyma yeasts, and rhamnolipids produced by Pseudomonas. Despite the current enthusiasm for these compounds several residual problems remain. This review highlights remaining problems and indicates the prospects for imminent commercial exploitation of a new generation of microbial biosurfactants. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. International petroleum exploration and exploitation agreements: a comprehensive environmental appraisal

    International Nuclear Information System (INIS)

    Zhiguo Gao

    1994-01-01

    The evolution of the environmental aspects of international petroleum exploration and exploitation is outlined. Four case studies of modern petroleum contracts from four developing countries are presented. These are Thailand's modern concession contract, Indonesia's production sharing contract, Brazil's risk service contract and China's hybrid contract. The failure of these four countries to provide adequate environmental regulation through their petroleum contracts is typical of many countries in the developing world. An urgent need exists to recognise that important environmental and resource consequences are associated with the developments authorised by petroleum contracts and that appropriate legal changes must be made to take them into account. Environmental sustainability should be an explicit part of all investment arrangements. (UK)

  13. Exploiting PV technology for basic need provision in Nigeria

    International Nuclear Information System (INIS)

    Gyoh, L.; Gyoh, S.

    2004-01-01

    Transitional economies are confronted with ever declining standard of living and low per capita income. Development institutions around the world have come to realize the strategic importance of Sustainable Energy as a Basic Need in the development process. Despite the efforts made by emerging democracies to eradicate poverty, there are still millions of people without access to electricity. Unreliable energy supply currently presents a constant obstacle to many poverty alleviation programmes. Against this background, some states government in Nigeria are exploiting the unique advantage offered by PV technology in the provision of Basic Needs. This study appraises some of the scheme in which the authors have been heavily involved with. This paper identifies some of the strategic policies that might accelerate the successful implementation of PV technology as a poverty alleviation tool in terms of electricity provision in transitional economies. (authors)

  14. Television production, Funding Models and Exploitation of Content

    Directory of Open Access Journals (Sweden)

    Gillian Doyle

    2016-07-01

    Full Text Available The rise of digital platforms has transformative implications for strategies of financing media production and for exploitation of the economic value in creative content. In the television industry, changes in technologies for distribution and the emergence of SVOD services such as Netflix are gradually shifting audiences and financial power away from broadcasters while at the same time creating unprecedented opportunities for programme-makers.  Drawing on findings from recent RCUK-funded research, this article examines how these shifts are affecting production financing and the economics of supplying television content.  In particular, it focuses on how changes in the dynamics of rights markets and in strategic approaches towards the financing of television production might mean for markets, industries and for policies intended to support the economic sustainability of independent television content production businesses.

  15. Exploitation and Benefits of BIM in Construction Project Management

    Science.gov (United States)

    Mesároš, Peter; Mandičák, Tomáš

    2017-10-01

    BIM is increasingly getting into the awareness in construction industry. BIM is the process of creating and data managing of the building during its life cycle. BIM became a part of management tools in modern construction companies. Construction projects have a number of participants. It means difficulty process of construction project management and a serious requirement for processing the huge amount of information including design, construction, time and cost parameters, economic efficiency and sustainability. Progressive information and communication technologies support cost management and management of construction project. One of them is Building Information Modelling. Aim of the paper is to examine the impact of BIM exploitation and benefits on construction project management in Slovak companies.

  16. Environmental impact of atomic minerals exploration and exploitation

    International Nuclear Information System (INIS)

    Dwivedy, K.K.

    1998-01-01

    Terrestrial radiation in the earth's environment is existing since its formation and is shared by all types of rocks, minerals, gases, and water, and to some extent aided by the interstellar radiation. Environmental radiation is ubiquitous and the man and other living beings have been living in such environment for thousands of years. Today they are much concerned about health and environmental risks so that a balance must be achieved between the activities that promote economic growth and the preservation of the natural environment. Atomic minerals are one of the main sources of natural environmental radiation and they are being explored by Atomic Minerals Division (AMD). Mining and milling activities sometimes may cause some radiological impacts but proper monitoring and remedial measures keep them under check. Some of the important aspects related to environmental impacts of uranium exploration and exploitation are presented

  17. Exploiting nonlinearities of micro-machined resonators for filtering applications

    KAUST Repository

    Ilyas, Saad; Chappanda, K. N.; Younis, Mohammad I.

    2017-01-01

    We demonstrate the exploitation of the nonlinear behavior of two electrically coupled microbeam resonators to realize a band-pass filter. More specifically, we combine their nonlinear hardening and softening responses to realize a near flat pass band filter with sharp roll-off characteristics. The device is composed of two near identical doubly clamped and electrostatically actuated microbeams made of silicon. One of the resonators is buckled via thermal loading to produce a softening frequency response. It is then further tuned to create the desired overlap with the second resonator response of hardening behavior. This overlapping improves the pass band flatness. Also, the sudden jumps due to the softening and hardening behaviors create sharp roll-off characteristics. This approach can be promising for the future generation of filters with superior characteristics.

  18. Analysis of ecological environment impact of coal exploitation and utilization

    Science.gov (United States)

    Zhang, Baoliu; Luo, Hong; Lv, Lianhong; Wang, Jian; Zhang, Baoshi

    2018-02-01

    Based on the theory of life cycle assessment, the ecological and environmental impacts of coal mining, processing, utilization and transportation will be analyzed, with analysing the status of china’s coal exploitation and utilization as the basis, it will find out the ecological and environmental impact in the development and utilization of coal, mainly consist of ecological impact including land damage, water resource destructionand biodiversity loss, etc., while the environmental impact include air, water, solid waste pollutions. Finally with a summary of the ecological and environmental problems, to propose solutionsand countermeasures to promote the rational development and consumption of coal, as well as to reduce the impact of coal production and consumption on the ecological environment, finally to achieve the coordinated development of energy and the environment.

  19. Exploiting nonlinearities of micro-machined resonators for filtering applications

    KAUST Repository

    Ilyas, Saad

    2017-06-21

    We demonstrate the exploitation of the nonlinear behavior of two electrically coupled microbeam resonators to realize a band-pass filter. More specifically, we combine their nonlinear hardening and softening responses to realize a near flat pass band filter with sharp roll-off characteristics. The device is composed of two near identical doubly clamped and electrostatically actuated microbeams made of silicon. One of the resonators is buckled via thermal loading to produce a softening frequency response. It is then further tuned to create the desired overlap with the second resonator response of hardening behavior. This overlapping improves the pass band flatness. Also, the sudden jumps due to the softening and hardening behaviors create sharp roll-off characteristics. This approach can be promising for the future generation of filters with superior characteristics.

  20. Tricking the guard: exploiting plant defense for disease susceptibility.

    Science.gov (United States)

    Lorang, J; Kidarsa, T; Bradford, C S; Gilbert, B; Curtis, M; Tzeng, S-C; Maier, C S; Wolpert, T J

    2012-11-02

    Typically, pathogens deploy virulence effectors to disable defense. Plants defeat effectors with resistance proteins that guard effector targets. We found that a pathogen exploits a resistance protein by activating it to confer susceptibility in Arabidopsis. The guard mechanism of plant defense is recapitulated by interactions among victorin (an effector produced by the necrotrophic fungus Cochliobolus victoriae), TRX-h5 (a defense-associated thioredoxin), and LOV1 (an Arabidopsis susceptibility protein). In LOV1's absence, victorin inhibits TRX-h5, resulting in compromised defense but not disease by C. victoriae. In LOV1's presence, victorin binding to TRX-h5 activates LOV1 and elicits a resistance-like response that confers disease susceptibility. We propose that victorin is, or mimics, a conventional pathogen virulence effector that was defeated by LOV1 and confers virulence to C. victoriae solely because it incites defense.