Science.gov

Sample records for kill invading microorganisms

  1. Killing Microorganisms with the One Atmosphere Uniform Glow Discharge Plasma

    NASA Astrophysics Data System (ADS)

    South, Suzanne; Kelly-Wintenberg, Kimberly; Montie, T. C.; Reece Roth, J.; Sherman, Daniel; Morrison, Jim; Chen, Zhiyu; Karakaya, Fuat

    2000-10-01

    There is an urgent need for the development of new technologies for sterilization and decontamination in the fields of healthcare and industrial and food processing that are safe, cost-effective, broad-spectrum, and not deleterious to samples. One technology that meets these criteria is the One Atmosphere Uniform Glow Discharge Plasma (OAUGDP). The OAUGDP operates in air and produces uniform plasma without filamentary discharges at room temperature, making this technology advantageous for sterilization of heat sensitive materials. The OAUGDP operates in a frequency band determined by the ion trapping mechanisms provided that, for air, the electric field is above 8.5kV/cm. The OAUGDP efficiently generates plasma reactive oxygen species (ROS) including atomic oxygen and oxygen free radicals without the requirement of a vacuum system. We have demonstrated the efficacy of the OAUGDP in killing microorganisms including bacteria, yeast, viruses, and spores in seconds to minutes on a variety of surfaces such as glass, films and fabrics, stainless steel, paper, and agar.

  2. Killing effect of peppermint vapor against pink-slime forming microorganisms.

    PubMed

    Ihara, Nozomi; Sakamoto, Jin; Yoshida, Munehiro; Tsuchido, Tetsuaki

    2015-01-01

    The killing effect of peppermint vapor (PMV) against pink-slime forming microorganisms, Methylobacterium mesophilicum as a bacterium and Rhodotorula mucilaginosa as a yeast, was investigated by the agar vapor assay. In this method, microbial cells were spread over the agar surface exposed to PMV in a petri dish, and then transferred into a recovery liquid. When 60μl of the peppermint liquid was added to a paper disc, a marked killing effect of PMV was observed after 48h against M. mesophilicum and after 168h against R. mucilaginosa. M. mesophilicum and R. mucilaginosa were found to be more resistant to PMV than Escherichia coli and Candida albicans, used as reference microorganisms, respectively. With the addition of 0.03% sodium pyruvate as a hydrogen peroxide scavenger in agar, the killing effect of PMV against E. coli and C. albicans was decreased, whereas it was little changed against M. mesophilicum and R. mucilaginosa. In fact, the properties of the killing effect of hydrogen peroxide solution at 0.2-1.0mM was in accord with those of PMV. M. mesophilicum and R. mucilaginosa were more resistant to the oxidant than E. coli and C. albicans, respectively. Results obtained suggested that reactive oxygen species (ROS) may be involved in the killing action of PMV and therefore pink-slime formers are more resistant to PMV than non-pink-slime formers because of the presence of carotenoids as an antioxidant in cells. We also suggest that the use of PMV appeared to be a potential tool for the control of pink-slime forming microorganisms occurring in wet areas of houses such as the bathroom and washing room. PMID:26133506

  3. Photothermal colloid antibodies for shape-selective recognition and killing of microorganisms.

    PubMed

    Borovička, Josef; Metheringham, William J; Madden, Leigh A; Walton, Christopher D; Stoyanov, Simeon D; Paunov, Vesselin N

    2013-04-10

    We have developed a class of selective antimicrobial agents based on the recognition of the shape and size of the bacterial cells. These agents are anisotropic colloid particles fabricated as negative replicas of the target cells which involve templating of the cells with shells of inert material followed by their fragmentation. The cell shape recognition by such shell fragments is due to the increased area of surface contact between the cells and their matching shell fragments which resembles antibody-antigen interaction. We produced such "colloid antibodies" with photothermal mechanism for shape-selective killing of matching cells. This was achieved by the subsequent deposition of (i) gold nanoparticles (AuNPs) and (ii) silica shell over yeast cells, which were chosen as model pathogens. We demonstrated that fragments of these composite AuNP/silica shells act as "colloid antibodies" and can bind to yeast cells of the same shape and size and deliver AuNPs directly onto their surface. We showed that after laser irradiation, the localized heating around the AuNPs kills the microbial cells of matching shape. We confirmed the cell shape-specific killing by photothermal colloid antibodies in a mixture of two bacterial cultures of different cell shape and size. This approach opens a number of avenues for building powerful selective biocides based on combinations of colloid antibodies and cell-killing strategies which can be applied in new antibacterial therapies. PMID:23540643

  4. Direct activation of human peritoneal mesothelial cells by heat-killed microorganisms.

    PubMed Central

    Kinnaert, P; De Wilde, J P; Bournonville, B; Husson, C; Salmon, I

    1996-01-01

    OBJECTIVE: The aim of the study was to determine if human peritoneal mesothelial cells (HPMCs) can be activated directly by bacterial products contained in preparations of heat-killed Escherichia coli and staphylococci. SUMMARY BACKGROUND DATA: It has been shown recently that cytokine-activated HPMCs produce the inflammatory mediators, interleukin-1, interleukin-6, interleukin-8, and macrophage chemotactic protein-1. Studies concerning the effects of bacterial products on HPMCs are scarce and have not yielded conclusive results. METHODS: Growth-arrested HPMC monolayers were prepared from cell suspensions obtained by enzymatic disaggregation of small pieces of omentum. They were incubated for 24 hours with heat-killed E. coli (ATCC 25922), heat-killed staphylococci (ATCC 25933), or E. coli lipopolysaccharide, and the release of various cytokines in the culture media was measured by radioimmunoassays or enzyme-linked immunosorbent assays. Results were expressed as mean +/- standard error of the mean in picograms per milliliter of supernatant and analyzed with the Wilcoxon test; p values of less than 0.05 were considered significant. RESULTS: Baseline production of interleukin-6, interleukin-8, the chemokine "regulated upon activation, normal T cell expressed and secreted" (RANTES), and macrophage chemotactic protein-1 varied widely from one omental preparation to the other. E. coli increased the release of these mediators: from 1206 +/- 316 pg/mL to 8480 +/- 2189 pg/mL for interleukin-6, from 285 +/- 58 pg/mL to 3164 +/- 1053 pg/mL for interleukin-8, from 7 +/- 5 pg/mL to 684 +/- 264 pg/mL for RANTES, and from 2212 +/- 346 pg/mL to 7726 +/- 1473 pg/mL for macrophage chemotactic protein-1. Heat-killed staphylococci did not alter significantly the production of RANTES or macrophage chemotactic protein-1 but increased the production of the two other cytokines from 1325 +/- 389 pg/mL to 2206 +/- 523 pg/mL for interleukin-6 and from 318 +/- 70 pg/mL to 819 +/- 265 pg/mL for interleukin-8. CONCLUSIONS: The authors' results show that HPMCs are able to react to a direct stimulation with heat-killed microbes. They suggest that HPMCs, as well as resident macrophages, participate actively in the initiation and possibly in the modulation of intraperitonen inflammatory reactions. PMID:8968229

  5. Short communication: Determination of the ability of Thymox to kill or inhibit various species of microorganisms associated with infectious causes of bovine lameness in vitro.

    PubMed

    Kulow, Megan; Zibaee, Fahimeh; Allard, Marianne; Döpfer, Dörte

    2015-11-01

    Infectious claw diseases continue to plague cattle in intensively managed husbandry systems. Poor foot hygiene and constant moist environments lead to the infection and spread of diseases such as digital dermatitis (hairy heel warts), interdigital dermatitis, and interdigital phlegmon (foot rot). Currently, copper sulfate and formalin are the most widely used disinfecting agents in bovine footbaths; however, the industry could benefit from more environmentally and worker friendly substitutes. This study determined the in vitro minimum inhibitory concentrations and minimum bactericidal concentrations of Thymox (Laboratoire M2, Sherbrooke, Québec, Canada) for a selection of microorganisms related to infectious bovine foot diseases. Thymox is a broad-spectrum agricultural disinfectant that is nontoxic, noncorrosive, and readily biodegradable. The values for minimum inhibitory concentration and minimum bactericidal concentration indicated that Thymox inhibited growth and killed the various species of microorganisms under study at much lower concentrations compared with the recommended working concentration of a 1% solution. Overall, the values found in this study of minimum inhibitory concentration and minimum bactericidal concentration of Thymox show its potential as an alternative antibacterial agent used in bovine footbaths; however, field trials are needed to determine its effectiveness for the control and prevention of infectious claw diseases. PMID:26364111

  6. Peroxynitrite, a potent macrophage-derived oxidizing cytotoxin to combat invading pathogens

    PubMed Central

    Prolo, Carolina; Álvarez, María Noel; Radi, Rafael

    2013-01-01

    Macrophages are among the first cellular actors facing the invasion of microorganisms. These cells are able to internalize pathogens and destroy them by means of toxic mediators, many of which are produced enzymatically and have strong oxidizing capacity. Indeed, macrophages count on the NADPH oxidase complex activity, which is triggered during pathogen invasion and leads to the production of superoxide radical inside the phagosome. At the same time, the induction of nitric oxide synthase results in the production of nitric oxide in the cytosol which is able to readily diffuse to the phagocytic vacuole. Superoxide radical and nitric oxide react at diffusion controlled rates with each other inside the phagosome to yield peroxynitrite, a powerful oxidant capable to kill microorganisms. Peroxynitrite toxicity resides on oxidations and nitrations of biomolecules in the target cell. The central role of peroxynitrite as a key effector molecule in the control of infections has been proven in a wide number of models. However, some microorganisms and virulent strains adapt to survive inside the potentially hostile oxidizing microenvironment of the phagosome by either impeding peroxynitrite formation or rapidly detoxifying it once formed. In this context, the outcome of the infection process is a result of the interplay between the macrophage-derived oxidizing cytotoxins such as peroxynitrite and the antioxidant defense machinery of the invading pathogens. PMID:24281946

  7. Killing Coyotes.

    ERIC Educational Resources Information Center

    Beasley, Conger, Jr.

    1993-01-01

    Presents different viewpoints concerning the federal government's Animal Damage Control (ADC) Program cited as responsible for killing millions of predators. Critics provide evidence of outdated and inhumane methods exemplified in the coyote killings. The ADC emphasizes new, nonlethal methods of controlling animals cited as "noxious." (MCO)

  8. Microorganism immobilization

    DOEpatents

    Compere, Alicia L.; Griffith, William L.

    1981-01-01

    Live metabolically active microorganisms are immobilized on a solid support by contacting particles of aggregate material with a water dispersible polyelectrolyte such as gelatin, crosslinking the polyelectrolyte by reacting it with a crosslinking agent such as glutaraldehyde to provide a crosslinked coating on the particles of aggregate material, contacting the coated particles with live microorganisms and incubating the microorganisms in contact with the crosslinked coating to provide a coating of metabolically active microorganisms. The immobilized microorganisms have continued growth and reproduction functions.

  9. A Drosera-bioinspired hydrogel for catching and killing cancer cells.

    PubMed

    Li, Shihui; Chen, Niancao; Gaddes, Erin R; Zhang, Xiaolong; Dong, Cheng; Wang, Yong

    2015-01-01

    A variety of bioinspired materials have been successfully synthesized to mimic the sophisticated structures or functions of biological systems. However, it is still challenging to develop materials with multiple functions that can be performed synergistically or sequentially. The purpose of this work was to demonstrate a novel bioinspired hydrogel that can interact with cancer cells, functionally similar to Drosera in catching and killing prey. This hydrogel had two layers with the top one functionalized with oligonucleotide aptamers and the bottom one functionalized with double-stranded DNA. The results show that the top hydrogel layer was able to catch target cells with high efficiency and specificity, and that the bottom hydrogel layer could sequester doxorubicin (Dox) for sustained drug release. Importantly, the released Dox could kill 90% of the cells after 1-h residence of the cells on the hydrogel. After the cell release, this bifunctional hydrogel could be regenerated for continuous cell catching and killing. Therefore, the data presented in this study has successfully demonstrated the potential of developing a material system with the functions of attracting, catching and killing diseased cells (e.g., circulating tumor cells) or even invading microorganisms (e.g., bacteria). PMID:26396063

  10. A Drosera-bioinspired hydrogel for catching and killing cancer cells

    PubMed Central

    Li, Shihui; Chen, Niancao; Gaddes, Erin R.; Zhang, Xiaolong; Dong, Cheng; Wang, Yong

    2015-01-01

    A variety of bioinspired materials have been successfully synthesized to mimic the sophisticated structures or functions of biological systems. However, it is still challenging to develop materials with multiple functions that can be performed synergistically or sequentially. The purpose of this work was to demonstrate a novel bioinspired hydrogel that can interact with cancer cells, functionally similar to Drosera in catching and killing prey. This hydrogel had two layers with the top one functionalized with oligonucleotide aptamers and the bottom one functionalized with double-stranded DNA. The results show that the top hydrogel layer was able to catch target cells with high efficiency and specificity, and that the bottom hydrogel layer could sequester doxorubicin (Dox) for sustained drug release. Importantly, the released Dox could kill 90% of the cells after 1-h residence of the cells on the hydrogel. After the cell release, this bifunctional hydrogel could be regenerated for continuous cell catching and killing. Therefore, the data presented in this study has successfully demonstrated the potential of developing a material system with the functions of attracting, catching and killing diseased cells (e.g., circulating tumor cells) or even invading microorganisms (e.g., bacteria). PMID:26396063

  11. Killing Range

    PubMed Central

    Asal, Victor; Rethemeyer, R. Karl; Horgan, John

    2015-01-01

    This paper presents an analysis of the Provisional Irish Republican Army's (PIRA) brigade level behavior during the Northern Ireland Conflict (1970-1998) and identifies the organizational factors that impact a brigade's lethality as measured via terrorist attacks. Key independent variables include levels of technical expertise, cadre age, counter-terrorism policies experienced, brigade size, and IED components and delivery methods. We find that technical expertise within a brigade allows for careful IED usage, which significantly minimizes civilian casualties (a specific strategic goal of PIRA) while increasing the ability to kill more high value targets with IEDs. Lethal counter-terrorism events also significantly affect a brigade's likelihood of killing both civilians and high-value targets but in different ways. Killing PIRA members significantly decreases IED fatalities but also significantly decreases the possibility of zero civilian IED-related deaths in a given year. Killing innocent Catholics in a Brigade's county significantly increases total and civilian IED fatalities. Together the results suggest the necessity to analyze dynamic situational variables that impact terrorist group behavior at the sub-unit level. PMID:25838603

  12. Killing fetuses and killing newborns.

    PubMed

    Di Nucci, Ezio

    2013-05-01

    The argument for the moral permissibility of killing newborns is a challenge to liberal positions on abortion because it can be considered a reductio of their defence of abortion. Here I defend the liberal stance on abortion by arguing that the argument for the moral permissibility of killing newborns on ground of the social, psychological and economic burden on the parents recently put forward by Giubilini and Minerva is not valid; this is because they fail to show that newborns cannot be harmed and because there are morally relevant differences between fetuses and newborns. PMID:23637456

  13. Beyond killing

    PubMed Central

    Vale, Pedro F.; McNally, Luke; Doeschl-Wilson, Andrea; King, Kayla C.; Popat, Roman; Domingo-Sananes, Maria R.; Allen, Judith E.; Soares, Miguel P.; Kümmerli, Rolf

    2016-01-01

    The antibiotic pipeline is running dry and infectious disease remains a major threat to public health. An efficient strategy to stay ahead of rapidly adapting pathogens should include approaches that replace, complement or enhance the effect of both current and novel antimicrobial compounds. In recent years, a number of innovative approaches to manage disease without the aid of traditional antibiotics and without eliminating the pathogens directly have emerged. These include disabling pathogen virulence-factors, increasing host tissue damage control or altering the microbiota to provide colonization resistance, immune resistance or disease tolerance against pathogens. We discuss the therapeutic potential of these approaches and examine their possible consequences for pathogen evolution. To guarantee a longer half-life of these alternatives to directly killing pathogens, and to gain a full understanding of their population-level consequences, we encourage future work to incorporate evolutionary perspectives into the development of these treatments. PMID:27016341

  14. [Foraging intensity of ants in Solenopsis invicta Buren (Hymenoptera: Formiciddae) invaded and un-invaded habitats].

    PubMed

    Wu, Bi-Qiu; Lu, Yong-Yue; Zeng, Ling; Song, Zhen-Dong; Liang, Guang-Wen

    2009-10-01

    By the methods of bait (honey, peanut oil, sausage, and mealworm larvae) trap, this paper studied the searching time, recruitment time, and recruitment number of ants in 3 typical habitats invaded and un-invaded by red imported fire ant (Solenopsis invicta) in South China, and analyzed the effects of S. invicta invasion on the foraging intensity of native ants. In S. invicta invaded lawn, the searching time of ants for mealworm larvae and peanut oil was significantly shorter, compared with that in S. invicta un-invaded area. Less difference was observed in the searching time for the 4 baits between S. invicta invaded and un-invaded wasteland, but the recruitment time for peanut oil was significantly longer in invaded than in un-invaded area. The searching time and recruitment time of the ants for the 4 baits had less difference between the invaded and un-invaded litchi orchard. 30 min after setting bait traps, the recruitment number of S. invicta workers on peanut oil, mealworm larvae, and sausage in invaded lawn, and on peanut oil in invaded wasteland was larger than that of native ants, but no significant difference was found in the recruitment number of S. invicta workers and native ants on the baits in invaded litchi orchard. PMID:20077713

  15. Activation of AMPK Enhances Neutrophil Chemotaxis and Bacterial Killing

    PubMed Central

    Park, Dae Won; Jiang, Shaoning; Tadie, Jean-Marc; Stigler, William S; Gao, Yong; Deshane, Jessy; Abraham, Edward; Zmijewski, Jaroslaw W

    2013-01-01

    An inability of neutrophils to eliminate invading microorganisms is frequently associated with severe infection and may contribute to the high mortality rates associated with sepsis. In the present studies, we examined whether metformin and other 5? adenosine monophosphate-activated protein kinase (AMPK) activators affect neutrophil motility, phagocytosis and bacterial killing. We found that activation of AMPK enhanced neutrophil chemotaxis in vitro and in vivo, and also counteracted the inhibition of chemotaxis induced by exposure of neutrophils to lipopolysaccharide (LPS). In contrast, small interfering RNA (siRNA)-mediated knockdown of AMPK?1 or blockade of AMPK activation through treatment of neutrophils with the AMPK inhibitor compound C diminished neutrophil chemotaxis. In addition to their effects on chemotaxis, treatment of neutrophils with metformin or aminoimidazole carboxamide ribonucleotide (AICAR) improved phagocytosis and bacterial killing, including more efficient eradication of bacteria in a mouse model of peritonitis-induced sepsis. Immunocytochemistry showed that, in contrast to LPS, metformin or AICAR induced robust actin polymerization and distinct formation of neutrophil leading edges. Although LPS diminished AMPK phosphorylation, metformin or AICAR was able to partially decrease the effects of LPS/toll-like receptor 4 (TLR4) engagement on downstream signaling events, particularly LPS-induced I?B? degradation. The I?B kinase (IKK) inhibitor PS-1145 diminished I?B? degradation and also prevented LPS-induced inhibition of chemotaxis. These results suggest that AMPK activation with clinically approved agents, such as metformin, may facilitate bacterial eradication in sepsis and other inflammatory conditions associated with inhibition of neutrophil activation and chemotaxis. PMID:24091934

  16. Activation of AMPK enhances neutrophil chemotaxis and bacterial killing.

    PubMed

    Park, Dae Won; Jiang, Shaoning; Tadie, Jean-Marc; Stigler, William S; Gao, Yong; Deshane, Jessy; Abraham, Edward; Zmijewski, Jaroslaw W

    2013-01-01

    An inability of neutrophils to eliminate invading microorganisms is frequently associated with severe infection and may contribute to the high mortality rates associated with sepsis. In the present studies, we examined whether metformin and other 5' adenosine monophosphate-activated protein kinase (AMPK) activators affect neutrophil motility, phagocytosis and bacterial killing. We found that activation of AMPK enhanced neutrophil chemotaxis in vitro and in vivo, and also counteracted the inhibition of chemotaxis induced by exposure of neutrophils to lipopolysaccharide (LPS). In contrast, small interfering RNA (siRNA)-mediated knockdown of AMPKα1 or blockade of AMPK activation through treatment of neutrophils with the AMPK inhibitor compound C diminished neutrophil chemotaxis. In addition to their effects on chemotaxis, treatment of neutrophils with metformin or aminoimidazole carboxamide ribonucleotide (AICAR) improved phagocytosis and bacterial killing, including more efficient eradication of bacteria in a mouse model of peritonitis-induced sepsis. Immunocytochemistry showed that, in contrast to LPS, metformin or AICAR induced robust actin polymerization and distinct formation of neutrophil leading edges. Although LPS diminished AMPK phosphorylation, metformin or AICAR was able to partially decrease the effects of LPS/toll-like receptor 4 (TLR4) engagement on downstream signaling events, particularly LPS-induced IκBα degradation. The IκB kinase (IKK) inhibitor PS-1145 diminished IκBα degradation and also prevented LPS-induced inhibition of chemotaxis. These results suggest that AMPK activation with clinically approved agents, such as metformin, may facilitate bacterial eradication in sepsis and other inflammatory conditions associated with inhibition of neutrophil activation and chemotaxis. PMID:24091934

  17. COMPARISON OF MEDUSAHEAD INVADED AND NON-INVADED WYOMING BIG SAGEBRUSH STEPPE IN SOUTHEASTERN OREGON

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Medusahead (Taeniatherum caput-medusae (L.) Nevski) is an exotic, annual grass invading sagebrush steppe rangelands in the western United States. Medusahead invasion has been demonstrated to reduce livestock forage, but otherwise information comparing vegetation characteristics of medusahead invade...

  18. Classifying Microorganisms.

    ERIC Educational Resources Information Center

    Baker, William P.; Leyva, Kathryn J.; Lang, Michael; Goodmanis, Ben

    2002-01-01

    Focuses on an activity in which students sample air at school and generate ideas about how to classify the microorganisms they observe. The results are used to compare air quality among schools via the Internet. Supports the development of scientific inquiry and technology skills. (DDR)

  19. Belowground competition among invading detritivores.

    PubMed

    Chang, Chih-Han; Szlavecz, Katalin; Filley, Timothy; Buyer, Jeffrey S; Bernard, Michael J; Pitz, Scott L

    2016-01-01

    The factors regulating soil animal communities are poorly understood. Current theory favors niche complementarity and facilitation over competition as the primary forms of non-trophic interspecific interaction in soil fauna; however, competition has frequently been suggested as an important community-structuring factor in earthworms, ecosystem engineers that influence belowground processes. To date, direct evidence of competition in earthworms is lacking due to the difficulty inherent in identifying a limiting resource for saprophagous animals. In the present study, we offer the first direct evidence of interspecific competition for food in this dominant soil detritivore group by combining field observations with laboratory mesocosm experiments using 13C and 15N double-enriched leaf litter to track consumption patterns. In our experiments, the Asian invasive species Amynthas hilgendorfi was a dominant competitor for leaf litter against two European species currently invading the temperate deciduous forests in North America. This competitive advantage may account for recent invasion success of A. hilgendorfi in forests with established populations of European species, and we hypothesize that specific phenological differences play an important role in determining the outcome of the belowground competition. In contrast, Eisenoides lonnbergi, a common native species in the Eastern United States, occupied a unique trophic position with limited interactions with other species, which may contribute to its persistence in habitats dominated by invasive species. Furthermore, our results supported neither the hypothesis that facilitation occurs between species of different functional groups nor the hypothesis that species in the same group exhibit functional equivalency in C and N translocation in the soil. We propose that species identity is a more powerful approach to understand earthworm invasion and its impacts on belowground processes. PMID:27008785

  20. Treponema pallidum Invades Intercellular Junctions of Endothelial Cell Monolayers

    NASA Astrophysics Data System (ADS)

    Thomas, D. Denee; Navab, Mahamad; Haake, David A.; Fogelman, Alan M.; Miller, James N.; Lovett, Michael A.

    1988-05-01

    The pathogenesis of syphilis reflects invasive properties of Treponema pallidum, but the actual mode of tissue invasion is unknown. We have found two in vitro parallels of treponemal invasiveness. We tested whether motile T. pallidum could invade host cells by determining the fate of radiolabeled motile organisms added to a HeLa cell monolayer; 26% of treponemes associated with the monolayer in a trypsin-resistant niche, presumably between the monolayer and the surface to which it adhered, but did not attain intracellularity. Attachment of T. pallidum to cultured human and rabbit aortic and human umbilical vein endothelial cells was 2-fold greater than to HeLa cells. We added T. pallidum to aortic endothelial cells grown on membrane filters under conditions in which tight intercellular junctions had formed. T. pallidum was able to pass through the endothelial cell monolayers without altering tight junctions, as measured by electrical resistance. In contrast, heat-killed T. pallidum and the nonpathogen Treponema phagedenis biotype Reiter failed to penetrate the monolayer. Transmission electron micrographs of sections of the monolayer showed T. pallidum in intercellular junctions. Our in vitro observations suggest that these highly motile spirochetes may leave the circulation by invading the junctions between endothelial cells.

  1. Revegetating sagebrush rangelands invaded by medusahead

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study are to determine: 1) effective treatments for controlling medusahead and 2) the appropriate plant materials for revegetating medusahead-invaded rangelands. Initial treatments of prescribed burning immediately followed with applications of the preemergent herbicide imazap...

  2. Revegetation of medusahead invaded sagebrush steppe

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Medusahead (Taeniatherum caput-medusae (L.) Nevski) is an exotic annual grass invading western rangelands. Invasion by medusahead is especially problematic because it decreases livestock forage production, degrades wildlife habitat, reduces biodiversity, and increases fire frequency. Revegetation ...

  3. Revegetating sagebrush rangelands invaded by medusahead

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to determine: 1) effective treatments for controlling medusahead and 2) the appropriate plant materials for revegetating medusahead-invaded rangelands. Initial treatments of prescribed burning immediately followed with applications of the preemergent herbicide imaza...

  4. Planning a dynamic kill

    SciTech Connect

    Abel, L.W.

    1996-05-01

    This article discusses the methodology, design philosophy, and guidelines for planning a dynamic-kill operation for a wild well. The topics covered are two methods of computer analysis for designing dynamic-kill requirements, the design process, determining the pumping spread, and the pitfalls that a designer faces in planning a dynamic kill.

  5. Ion-kill dosimetry

    NASA Technical Reports Server (NTRS)

    Katz, R.; Cucinotta, F. A.; Fromm, M.; Chambaudet, A.

    2001-01-01

    Unanticipated late effects in neutron and heavy ion therapy, not attributable to overdose, imply a qualitative difference between low and high LET therapy. We identify that difference as 'ion kill', associated with the spectrum of z/beta in the radiation field, whose measurement we label 'ion-kill dosimetry'.

  6. Strong invaders are strong defenders - implications for the resistance of invaded communities.

    PubMed

    Henriksson, Anna; Wardle, David A; Trygg, Johan; Diehl, Sebastian; Englund, Göran

    2016-04-01

    Many ecosystems receive a steady stream of non-native species. How biotic resistance develops over time in these ecosystems will depend on how established invaders contribute to subsequent resistance. If invasion success and defence capacity (i.e. contribution to resistance) are correlated, then community resistance should increase as species accumulate. If successful invaders also cause most impact (through replacing native species with low defence capacity) then the effect will be even stronger. If successful invaders instead have weak defence capacity or even facilitative attributes, then resistance should decrease with time, as proposed by the invasional meltdown hypothesis. We analysed 1157 introductions of freshwater fish in Swedish lakes and found that species' invasion success was positively correlated with their defence capacity and impact, suggesting that these communities will develop stronger resistance over time. These insights can be used to identify scenarios where invading species are expected to cause large impact. PMID:26947421

  7. Cloning, killing, and identity.

    PubMed Central

    McMahan, J

    1999-01-01

    One potentially valuable use of cloning is to provide a source of tissues or organs for transplantation. The most important objection to this use of cloning is that a human clone would be the sort of entity that it would be seriously wrong to kill. I argue that entities of the sort that you and I essentially are do not begin to exist until around the seventh month of fetal gestation. Therefore to kill a clone prior to that would not be to kill someone like you or me but would be only to prevent one of us from existing. And even after one of us begins to exist, the objections to killing it remain comparatively weak until its psychological capacities reach a certain level of maturation. These claims support the permissibility of killing a clone during the early stages of its development in order to use its organs for transplantation. PMID:10226909

  8. Effect of microwaves on microorganisms in foods

    SciTech Connect

    Fung, D.Y.C.; Cunningham, F.E.

    1980-08-01

    The microbial safety of foods cooked in microwave ovens was investigated. The mechanisms of microwave destruction of microorganisms were examined. Effects of time and temperature on microorganisms in different food systems were described. Studies showed that: microwave heating of food is more ''''food dependent'' than conventional heating; recommended microwave treatment time for some foods may not destroy high levels of bacteria; use of microwaves in combination with conventional heating methods results in more uniform heating of foods and destruction of bacteria; and microwaves exert different killing effects on individual bacterial species. (78 references, 2 tables)

  9. FISH KILLS, NORTH CAROLINA

    EPA Science Inventory

    Data related to fish kills in North Carolina are collected and stored in tables on the Web at the North Carolina Department of Environment and Natural Resources. http://www.esb.enr.state.nc.us/Fishkill/fishkill00.htm

  10. Porphyromonas gingivalis invades oral epithelial cells in vitro.

    PubMed

    Sandros, J; Papapanou, P; Dahlén, G

    1993-05-01

    The aim of the present study was to analyze the adhesive and invasive potential of a number of P. gingivalis strains, in an in vitro system utilizing cultures of human oral epithelial cells (KB cell line, ATCC CCL 17). P. gingivalis strains W50 and FDC 381 (laboratory strains) and OMGS 1738, 1743 and 1439 (clinical isolates) as well as E. coli strain HB 101 (non-adhering, non-invasive control) were used. Adherence was assessed by means of scintillation counting and light microscopy, after incubation of radiolabelled bacteria with epithelial cells. In the invasion assay, monolayers were infected with the P. gingivalis and E. coli strains and further incubated with an antibiotic mixture (metronidazole 0.1 mg/ml and gentamicin 0.5 mg/ml). Invasion was evaluated by (i) assessing presence of bacteria surviving the antibiotic treatment, and (ii) electron microscopy. All P. gingivalis strains adhered to and entered into the oral epithelial cells. After 3 hours of incubation, bacteria were frequently identified intracellularly by means of electron microscopy. The cellular membranes, encapsulating the microorganisms in early stages of the invasive process, appeared later to disintegrate. The presence of coated pits on the epithelial cell surfaces suggested that internalization of P. gingivalis was associated with receptor-mediated endocytosis (RME). Formation of outer membrane vesicles (blebs) by intracellular bacteria indicated that internalized P. gingivalis was able to retain its viability. E. coli strain HB 101 neither adhered to nor invaded epithelial cells. PMID:8388449

  11. Chinese Tallow: Invading the Southeastern Coastal Plain

    USGS Publications Warehouse

    U.S. Geological Survey

    2000-01-01

    Chinese tallow is an ornamental tree with colorful autumn foliage that can survive full sunlight and shade, flooding, drought, and in some cases fire. To horticulturists this kind of tree sounds like a dream, but to ecologists, land managers, and land owners this kind of tree can be a nightmare, especially when it invades an area and takes over native vegetation. Chinese tallow (Triadica sebifera), a nonnative tree from China, is currently transforming the southeastern Coastal Plain. Over the last 30 years, Chinese tallow has become a common tree in old fields and bottomland swamps of coastal Louisiana. Several studies at the U.S. Geological Survey's National Wetlands Research Center (NWRC), Lafayette, Louisiana, are aimed at understanding the factors that contribute to Chinese tallow growth, spread, and management. When tallow invades, it eventually monopolizes an area, creating a forest without native animal or plant species. This tree exhibits classic traits of most nonnative invaders: it is attractive so people want to distribute it, it has incredible resiliency, it grows quickly and in a variety of soils, and it is resistant to pests. In the coastal prairie of Louisiana and Texas, Chinese tallow can grow up to 30 feet and shade out native sun-loving prairie species. The disappearing of prairie species is troublesome because less than 1% of original coastal prairie remains, and in Louisiana, less than 500 of the original 2.2 million acres still exist. Tallow reproduces and grows quickly and can cause large-scale ecosystem modification (fig. 1). For example, when it completely replaces native vegetation, it has a negative effect on birds by degrading the habitat. Besides shading out grasses that cattle like to eat, it can also be potentially harmful to humans and animals because of its berries (fig. 2) and plant sap that contain toxins. There is some concern its leaves may shed toxins that change the soil chemistry and make it difficult for other plants to grow.

  12. Age Invaders: Entertainment for Elderly and Young

    NASA Astrophysics Data System (ADS)

    Cheok, Adrian David

    This chapter presents the design process of Age Invaders, an intergenerational family entertainment system which focuses on physical and social interactions using a mixed reality floor system. The main design goals include facilitating interactions between users with varied levels of skill in utilizing technology, utilizing the familiar physical motions from other activities to make an intuitive physical interface, and encouraging social interactions among families and friends. Four main prototype iterations for the system are presented. Our design process is based on User Centered Design and relies on constant involvement of users to understand the key issues and to help make effective design decisions. The results of the study help to focus the refinements of the existing platform from a usability standpoint and also aid in the development of new physical entertainment and interactive applications. This study provides insights into user issues including how users interact in a complex mixed reality experience. At the end of this chapter, we presented the design of a toolkit that enables easy access and programming of the Age Invaders system. This toolkit could be used as a general platform for designing and reprogramming new type of artwork, entertainment, games, and applications.

  13. Combating Antimicrobial Resistance in Foodborne Microorganisms.

    PubMed

    Lai, Edward P C; Iqbal, Zafar; Avis, Tyler J

    2016-02-01

    This review addresses an important public health hazard affecting food safety. Antimicrobial agents are used in foods to reduce or eliminate microorganisms that cause disease. Many traditional organic compounds, novel synthetic organic agents, natural products, peptides, and proteins have been extensively studied for their effectiveness as antimicrobial agents against foodborne Campylobacter spp., Escherichia coli, Listeria spp. and Salmonella. However, antimicrobial resistance can develop in microorganisms, enhancing their ability to withstand the inhibiting or killing action of antimicrobial agents. Knowledge gaps still exist with regard to the actual chemical and microbiological mechanisms that must be identified to facilitate the search for new antimicrobial agents. Technical implementation of antimicrobial active packing films and coatings against target microorganisms must also be improved for extended product shelf life. Recent advances in antimicrobial susceptibility testing can provide researchers with new momentum to pursue their quest for a resistance panacea. PMID:26818996

  14. Redshifts and Killing vectors

    NASA Astrophysics Data System (ADS)

    Harvey, Alex; Schucking, Engelbert; Surowitz, Eugene J.

    2006-11-01

    Current approaches to physics stress the importance of conservation laws due to spacetime and internal symmetries. In special and general relativity the generators of these symmetries are known as Killing vectors. We use them for the rigorous determination of gravitational and cosmological redshifts.

  15. Children Who Kill.

    ERIC Educational Resources Information Center

    Natale, Jo Anna

    1999-01-01

    Two recent books, "When Good Kids Kill," by Michael D. Kelleher, and "Lost Boys," by James Garbarino, explore how children become killers and suggest ways to reduce our high-pressure society's epidemic levels of youth violence. Physically or psychologically distant parents and unaffirmative media messages are negative influences. (MLH)

  16. Killing vectors and anisotropy

    SciTech Connect

    Krisch, J. P.; Glass, E. N.

    2009-08-15

    We consider an action that can generate fluids with three unequal stresses for metrics with a spacelike Killing vector. The parameters in the action are directly related to the stress anisotropies. The field equations following from the action are applied to an anisotropic cosmological expansion and an extension of the Gott-Hiscock cosmic string.

  17. Interference competition among native and invader amphipods

    NASA Astrophysics Data System (ADS)

    van Riel, Mariëlle C.; Healy, Evan P.; van der Velde, Gerard; bij de Vaate, Abraham

    2007-05-01

    Aquarium experiments were used to study indications of interference competition, such as substratum choice shifts, swimming activities and mortality of invasive and indigenous gammarids in each other's presence. The more recent invaders Gammarus tigrinus and Dikerogammarus villosus were more likely to prefer stone substratum, whereas the native Gammarus pulex and an earlier invader Gammarus roeseli were found more frequently in the water layer. Sand was the least likely substratum to be chosen by any of the species. G. pulex and G. roeseli did not alter their substratum preference in each other's presence. In the presence of D. villosus, G. pulex shifted towards smaller stones and increased its swimming activities, whereas D. villosus did not change its behaviour in the presence of G. pulex. These shifts may indicate interference competition, with D. villosus being the stronger competitor. The greatest shifts in substratum preference arose when one species had occupied a substratum before the other one was introduced, especially when D. villosus was already present before G. pulex was introduced, possibly indicating pre-emptive competition. Swimming activities of G. pulex increased in the presence of D. villosus, whereas D. villosus spent little time swimming. Mortality was comparable between the different experiments without any indication of predation. The effect of Intra Guild Predation (IGP) may not be reflected adequately by short-time experiments as moults occurred seldom during the experiments. Although no IGP was observed during our experiments, habitat shifts occurred, which may indicate that competitive interactions are apparent before IGP starts. Such shifts may serve to avoid intraguild competition.

  18. Interpopulation variation in allelopathic traits informs restoration of invaded landscapes

    PubMed Central

    Lankau, Richard A

    2012-01-01

    Invasive species can show substantial genetic variation in ecologically important traits, across ranges as well within the introduced range. If these traits affect competition with native species, then management may benefit from considering the genetic landscape of the invader. Across their introduced range, Alliaria petiolata populations vary in their investment in allelopathic traits according to invasion history, which could lead to gradients of impact on native species. Red oak (Quercus rubra) seedlings were transplanted into eight A. petiolata-invaded sites that varied in their invasion history and allelochemical concentrations. At each site, an invader removal treatment was crossed with experimental inoculations of native soil biota, to test whether the benefits of these restoration actions differed across invader populations. Q. rubra seedlings grew faster in invader populations with a longer invasion history and lower allelochemical concentrations. Invader removal and soil inoculation interacted to determine seedling growth, with the benefits of soil inoculation increasing in younger and more highly allelopathic invader populations. A greenhouse experiment using soils collected from experimentally inoculated field plots found similar patterns. These results suggest that the impact of this invader varies across landscapes and that knowledge of this variation could improve the efficacy and efficiency of restoration activities. PMID:25568047

  19. Donor and recipient regions: The biogeography of macrobenthic invaders

    EPA Science Inventory

    Aquatic invaders are a major threat to ecological integrity and biodiversity of marine, estuarine, and freshwater ecosystems around the world. These invaders have been successful in passing through four discrete phases in their invasion of a new environment: (1) transport, (2) ...

  20. Brucella melitensis Invades Murine Erythrocytes during Infection

    PubMed Central

    Vitry, Marie-Alice; Hanot Mambres, Delphine; Deghelt, Michaël; Hack, Katrin; Machelart, Arnaud; Lhomme, Frédéric; Vanderwinden, Jean-Marie; Vermeersch, Marjorie; De Trez, Carl; Pérez-Morga, David; Letesson, Jean-Jacques

    2014-01-01

    Brucella spp. are facultative intracellular Gram-negative coccobacilli responsible for brucellosis, a worldwide zoonosis. We observed that Brucella melitensis is able to persist for several weeks in the blood of intraperitoneally infected mice and that transferred blood at any time point tested is able to induce infection in naive recipient mice. Bacterial persistence in the blood is dramatically impaired by specific antibodies induced following Brucella vaccination. In contrast to Bartonella, the type IV secretion system and flagellar expression are not critically required for the persistence of Brucella in blood. ImageStream analysis of blood cells showed that following a brief extracellular phase, Brucella is associated mainly with the erythrocytes. Examination by confocal microscopy and transmission electron microscopy formally demonstrated that B. melitensis is able to invade erythrocytes in vivo. The bacteria do not seem to multiply in erythrocytes and are found free in the cytoplasm. Our results open up new areas for investigation and should serve in the development of novel strategies for the treatment or prophylaxis of brucellosis. Invasion of erythrocytes could potentially protect the bacterial cells from the host's immune response and hamper antibiotic treatment and suggests possible Brucella transmission by bloodsucking insects in nature. PMID:25001604

  1. Isolated Retroperitoneal Hydatid Cyst Invading Splenic Hilum

    PubMed Central

    Ozturk, Safak; Unver, Mutlu; Kibar Ozturk, Burcin; Kebapci, Eyup; Bozbiyik, Osman; Erol, Varlık; Zalluhoglu, Nihat; Olmez, Mustafa

    2014-01-01

    Introduction. Hydatid disease (HD) is an infestation that is caused by the larval stage of Echinococcus granulosus. The liver is affected in approximately two-thirds of patients, the lungs in 25%, and other organs in a small proportion. Primary retroperitoneal hydatid cyst is extremely rare. The most common complaint is abdominal pain; however, the clinical features of HD may be generally dependent on the location of the cyst. Case Presentation. A 43-year-old female was admitted with the complaint of abdominal pain. Her physical examination was normal. Computed tomography (CT) revealed a 17 × 11 cm cystic lesion, with a thick and smooth wall that is located among the left liver lobe, diaphragm, spleen, tail of the pancreas, and transverse colon and invading the splenic hilum. Total cystectomy and splenectomy were performed. Pathological examination was reported as cyst hydatid. Discussion. Cysts in the peritoneal cavity are mainly the result of the spontaneous or traumatic rupture of concomitant hepatic cysts or surgical inoculation of a hepatic cyst. Serological tests contribute to diagnosis. In symptomatic and large hydatid peritoneal cysts, surgical resection is the only curative treatment. Total cystectomy is the gold standard. Albendazole or praziquantel is indicated for inoperable and disseminated cases. Percutaneous aspiration, injection, and reaspiration (PAIR) technique is another nonsurgical option. PMID:24790764

  2. Microorganisms and Chemical Pollution

    ERIC Educational Resources Information Center

    Alexander, M.

    1973-01-01

    Discusses the importance of microorganisms in chemical pollution and pollution abatement. Selected chemical pollutants are chosen to illustrate that microorganisms synthesize hazardous substances from reasonably innocuous precursors, while others act as excellent environmental decontaminating agents by removing undesirable natural and synthetic…

  3. Microorganisms and Chemical Pollution

    ERIC Educational Resources Information Center

    Alexander, M.

    1973-01-01

    Discusses the importance of microorganisms in chemical pollution and pollution abatement. Selected chemical pollutants are chosen to illustrate that microorganisms synthesize hazardous substances from reasonably innocuous precursors, while others act as excellent environmental decontaminating agents by removing undesirable natural and synthetic

  4. Adolescents who kill.

    PubMed

    Busch, K G; Zagar, R; Hughes, J R; Arbit, J; Bussell, R E

    1990-07-01

    From a sample of 1,956 adolescent delinquents referred to us by the court for physical, psychological, psychiatric, educational, and social examinations, 71 delinquents convicted of homicide were matched with 71 nonviolent delinquents by age, race, sex, and socioeconomic status (SES). These two groups were compared on the basis of these evaluations by stepwise discriminant analysis, matched pairs, two-tailed t-tests, and nonparametric tests. Adolescents who kill have a tetrad of symptoms: (1) criminally violent family members; (2) gang membership; (3) severe educational difficulties; and (4) alcohol abuse. PMID:2212052

  5. Charged conformal Killing spinors

    SciTech Connect

    Lischewski, Andree

    2015-01-15

    We study the twistor equation on pseudo-Riemannian Spin{sup c}-manifolds whose solutions we call charged conformal Killing spinors (CCKSs). We derive several integrability conditions for the existence of CCKS and study their relations to spinor bilinears. A construction principle for Lorentzian manifolds admitting CCKS with nontrivial charge starting from CR-geometry is presented. We obtain a partial classification result in the Lorentzian case under the additional assumption that the associated Dirac current is normal conformal and complete the classification of manifolds admitting CCKS in all dimensions and signatures ≤5 which has recently been initiated in the study of supersymmetric field theories on curved space.

  6. Two Different Rickettsial Bacteria Invading Volvox carteri

    PubMed Central

    Kawafune, Kaoru; Hongoh, Yuichi; Hamaji, Takashi; Sakamoto, Tomoaki; Kurata, Tetsuya; Hirooka, Shunsuke; Miyagishima, Shin-ya; Nozaki, Hisayoshi

    2015-01-01

    Background Bacteria of the family Rickettsiaceae are principally associated with arthropods. Recently, endosymbionts of the Rickettsiaceae have been found in non-phagotrophic cells of the volvocalean green algae Carteria cerasiformis, Pleodorina japonica, and Volvox carteri. Such endosymbionts were present in only C. cerasiformis strain NIES-425 and V. carteri strain UTEX 2180, of various strains of Carteria and V. carteri examined, suggesting that rickettsial endosymbionts may have been transmitted to only a few algal strains very recently. However, in preliminary work, we detected a sequence similar to that of a rickettsial gene in the nuclear genome of V. carteri strain EVE. Methodology/Principal Findings Here we explored the origin of the rickettsial gene-like sequences in the endosymbiont-lacking V. carteri strain EVE, by performing comparative analyses on 13 strains of V. carteri. By reference to our ongoing genomic sequence of rickettsial endosymbionts in C. cerasiformis strain NIES-425 cells, we confirmed that an approximately 9-kbp DNA sequence encompassing a region similar to that of four rickettsial genes was present in the nuclear genome of V. carteri strain EVE. Phylogenetic analyses, and comparisons of the synteny of rickettsial gene-like sequences from various strains of V. carteri, indicated that the rickettsial gene-like sequences in the nuclear genome of V. carteri strain EVE were closely related to rickettsial gene sequences of P. japonica, rather than those of V. carteri strain UTEX 2180. Conclusion/Significance At least two different rickettsial organisms may have invaded the V. carteri lineage, one of which may be the direct ancestor of the endosymbiont of V. carteri strain UTEX 2180, whereas the other may be closely related to the endosymbiont of P. japonica. Endosymbiotic gene transfer from the latter rickettsial organism may have occurred in an ancestor of V. carteri. Thus, the rickettsiae may be widely associated with V. carteri, and likely have often been lost during host evolution. PMID:25671568

  7. Kill operation requires thorough analysis

    SciTech Connect

    Abel, L.W.

    1995-05-15

    Full control of a blowout well requires a properly designed post-capping kill operation because failures in regaining well control usually occur during the kill operation, not during capping. Capping (the installation of pressure control or diverter equipment on the wellhead) is generally very reliable in gaining control of a blowout well. The following techniques are some of the viable means of killing blowout wells once the capping assemblies are in place: direct shut in of the flow; bullheading; momentum kill; volumetric control for migration of fluids or lubrication after migration ceases; and dynamic kills (friction-based dynamic kills or mass flow rate kills) The objective of most post-capping operations is to stop the flow and put the well under hydrostatic control. The means of killing a blowout once capping assemblies are in place should be chosen with care to avoid problems such as cratering, equipment failure, and underground blowouts. The particular circumstances and well integrity will dictate which kill method will be the most viable. Each of these five methods are explained.

  8. Micro-organ device

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R. (Inventor); von Gustedt-Gonda, legal representative, Iris (Inventor); Chang, Robert C. (Inventor); Starly, Binil (Inventor); Culbertson, Christopher (Inventor); Holtorf, Heidi L. (Inventor); Sun, Wei (Inventor); Leslie, Julia (Inventor)

    2013-01-01

    A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

  9. Micro-Organ Device

    NASA Technical Reports Server (NTRS)

    Gonda, Steve R. (Inventor); Chang, Robert C. (Inventor); Starly, Binil (Inventor); Culbertson, Christopher (Inventor); Holtorf, Heidi L. (Inventor); Sun, Wei (Inventor); Leslie, Julia (Inventor)

    2013-01-01

    A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

  10. Killing spinors on Lorentzian manifolds

    NASA Astrophysics Data System (ADS)

    Bohle, Christoph

    2003-03-01

    The aim of this paper is to describe some results concerning the geometry of Lorentzian manifolds admitting Killing spinors. We prove that there are imaginary Killing spinors on simply connected Lorentzian Einstein-Sasaki manifolds. In the Riemannian case, an odd-dimensional complete simply connected manifold (of dimension n≠7) is Einstein-Sasaki if and only if it admits a non-trivial Killing spinor to λ=± {1}/{2}. The analogous result does not hold in the Lorentzian case. We give an example of a non-Einstein Lorentzian manifold admitting an imaginary Killing spinor. A Lorentzian manifold admitting a real Killing spinor is at least locally a codimension one warped product with a special warping function. The fiber of the warped product is either a Riemannian manifold with a real or imaginary Killing spinor or with a parallel spinor, or it again is a Lorentzian manifold with a real Killing spinor. Conversely, all warped products of that form admit real Killing spinors.

  11. Development of static system procedures to study aquatic biofilms and their responses to disinfection and invading species

    NASA Technical Reports Server (NTRS)

    Smithers, G. A.

    1992-01-01

    The microbial ecology facility in the Analytical and Physical Chemistry Branch at Marshall Space Flight Center is tasked with anticipation of potential microbial problems (and opportunities to exploit microorganisms) which may occur in partially closed systems such as space station/vehicles habitats and in water reclamation systems therein, with particular emphasis on the degradation of materials. Within this context, procedures for microbial biofilm research are being developed. Reported here is the development of static system procedures to study aquatic biofilms and their responses to disinfection and invading species. Preliminary investigations have been completed. As procedures are refined, it will be possible to focus more closely on the elucidation of biofilm phenomena.

  12. Fossil Microorganisms in Archaean

    NASA Technical Reports Server (NTRS)

    Astafleva, Marina; Hoover, Richard; Rozanov, Alexei; Vrevskiy, A.

    2006-01-01

    Ancient Archean and Proterozoic rocks are the model objects for investigation of rocks comprising astromaterials. The first of Archean fossil microorganisms from Baltic shield have been reported at the last SPIE Conference in 2005. Since this confeence biomorphic structures have been revealed in Archean rocks of Karelia. It was determined that there are 3 types of such bion structures: 1. structures found in situ, in other words microorganisms even-aged with rock matrix, that is real Archean fossils biomorphic structures, that is to say forms inhabited early formed rocks, and 3. younger than Archean-Protherozoic minerali microorganisms, that is later contamination. We made attempt to differentiate these 3 types of findings and tried to understand of burial of microorganisms. The structures belongs (from our point of view) to the first type, or real Archean, forms were under examination. Practical investigation of ancient microorganisms from Green-Stone-Belt of Northern Karelia turns to be very perspective. It shows that even in such ancient time as Archean ancient diverse world existed. Moreover probably such relatively highly organized cyanobacteria and perhaps eukaryotic formes existed in Archean world.

  13. Micro-Organ Devices

    NASA Technical Reports Server (NTRS)

    Gonda, Steven R.; Leslie, Julia; Chang, Robert C.; Starly, Binil; Sun, Wei; Culbertson, Christopher; Holtorf, Heidi

    2009-01-01

    Micro-organ devices (MODs) are being developed to satisfy an emerging need for small, lightweight, reproducible, biological-experimentati on apparatuses that are amenable to automated operation and that imp ose minimal demands for resources (principally, power and fluids). I n simplest terms, a MOD is a microfluidic device containing a variety of microstructures and assemblies of cells, all designed to mimic a complex in vivo microenvironment by replicating one or more in vivo micro-organ structures, the architectures and composition of the extr acellular matrices in the organs of interest, and the in vivo fluid flows. In addition to microscopic flow channels, a MOD contains one or more micro-organ wells containing cells residing in microscopic e xtracellular matrices and/or scaffolds, the shapes and compositions o f which enable replication of the corresponding in vivo cell assembl ies and flows.

  14. (Genetically engineered microorganisms)

    SciTech Connect

    Sharples, F.E.

    1988-04-18

    The traveler attended the First International Conference on the Release of Genetically Engineered Microorganisms at the request of the United Nations Environment Programme (UNEP). The purpose of the conference was to provide an international forum for the discussion of the issues and concerns related to the release of genetically engineered microorganisms for environmental and agricultural applications. The cost of attendance was paid by UNEP, a group with whom a small Work-for-Others contract (to participate in developing international biosafety guidelines) is under discussion.

  15. Notes on super Killing tensors

    NASA Astrophysics Data System (ADS)

    Howe, P. S.; Lindström, U.

    2016-03-01

    The notion of a Killing tensor is generalised to a superspace setting. Conserved quantities associated with these are defined for superparticles and Poisson brackets are used to define a supersymmetric version of the even Schouten-Nijenhuis bracket. Superconformal Killing tensors in flat superspaces are studied for spacetime dimensions 3,4,5,6 and 10. These tensors are also presented in analytic superspaces and super-twistor spaces for 3,4 and 6 dimensions. Algebraic structures associated with superconformal Killing tensors are also briefly discussed.

  16. Microorganisms and Man.

    ERIC Educational Resources Information Center

    Noble, W. C.

    1983-01-01

    Provides information to update Institute of Biology's Studies in Biology No. 111, "Microorganisms and Man," by W. C. Noble and Jay Naidoo (Edward Arnold, 1979). Topics include: (1) food poisoning; (2) airborn infections in man; (3) infection in animals and plants; and (4) biodegradation and biosynthesis. (JN)

  17. Subsurface Microorganisms: Ecological significance

    SciTech Connect

    Fredrickson, Jim K.

    2003-01-15

    Terrestrial subsurface environments are inhabited almost exclusively by microorganisms and are in essence 'aphotic' ecosystems. Photosynthesis plays only an indirect role in subsurface microbial ecology, providing reduced organic compounds that can be metabolized by aerobic or anaerobic heterotrophic bacteria. Organic compounds are introduced into the subsurface, in general, via burial of detrital organic matter or as solutes that are transported to the subsurface in the form of dissolved organic carbon (DOC) in waters that percolate downward and recharge aquifers. Microbial generation of energy in deep subsurface environments results from biochemical reactions involving the oxidation of reduced compounds and the subsequent transfer of electrons to an adjacent oxidized compound. It is these metabolic processes that have a great impact on microbial ecological interactions in the subsurface and subsequent impacts of microbial metabolism on groundwater geochemistry and geological processes such as diagenesis (1). This article will provide an overview of the sources of energy that drive microbial metabolism in the subsurface and the physical constraints on the presence and function of subsurface microorganisms. The distributions and general characteristics of microorganisms in the subsurface will be examined and critical issues with regards to sampling the subsurface and enumerating associated microorganisms will be discussed. Finally, the extent of the subsurface biosphere on earth will be explored along with how this concept has focused the search for life elsewhere in the solar system to the subsurface of other planetary bodies.

  18. Phantom metrics with Killing spinors

    NASA Astrophysics Data System (ADS)

    Sabra, W. A.

    2015-11-01

    We study metric solutions of Einstein-anti-Maxwell theory admitting Killing spinors. The analogue of the IWP metric which admits a space-like Killing vector is found and is expressed in terms of a complex function satisfying the wave equation in flat (2 + 1)-dimensional space-time. As examples, electric and magnetic Kasner spaces are constructed by allowing the solution to depend only on the time coordinate. Euclidean solutions are also presented.

  19. Culture Clash Invades Miami: Oral Histories and Ethnography Center Stage

    ERIC Educational Resources Information Center

    Garcia, David G.

    2008-01-01

    Using a critical race theory (CRT) framework, this article compares the playwriting methods of the Chicano--Latino theater trio, Culture Clash, to a counterstorytelling methodology. The author uncovers the tenets of a critical race theater in the trio's site-specific ethnographic play, "Radio Mambo: Culture Clash Invades Miami". He argues that…

  20. Revegetating medusahead-invaded sagebrush rangelands in the intermountain west

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Revegetation of medusahead-invaded rangeland is needed to increase forage production, decrease the risk of wildfires, and improve wildlife habitat. Successful revegetation starts with effective control of medusahead. Prescribed burning followed by a fall application of a pre-emergent herbicide has...

  1. Grassland Invader Responses to Realistic Changes in Native Species Richness

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is major concern that declining biodiversity could promote exotic plant invasions. Consequently, many studies have subjected colonizing invaders to a range of species richness levels in order to clarify the role of biodiversity in repelling invasions. These studies have provided critical ins...

  2. Inactivation of Microorganisms

    NASA Astrophysics Data System (ADS)

    Alzamora, Stella Maris; Guerrero, Sandra N.; Schenk, Marcela; Raffellini, Silvia; López-Malo, Aurelio

    Minimal processing techniques for food preservation allow better retention of product flavor, texture, color, and nutrient content than comparable conventional treatments. A wide range of novel alternative physical factors have been intensely investigated in the last two decades. These physical factors can cause inactivation of microorganisms at ambient or sublethal temperatures (e.g., high hydrostatic pressure, pulsed electric fields, ultrasound, pulsed light, and ultraviolet light). These technologies have been reported to reduce microorganism population in foods while avoiding the deleterious effects of severe heating on quality. Among technologies, high-energy ultrasound (i.e., intensities higher than 1 W/cm2, frequencies between 18 and 100 kHz) has attracted considerable interest for food preservation applications (Mason et al., 1996; Povey and Mason, 1998).

  3. Formation fracturing kills Indonesian blowout

    SciTech Connect

    Wizyodiazjo, S.; Salech, M.; Sumanta, K.

    1982-11-15

    Dynamic killing methods without fracturing could not be applied in killing PT-29 blowout, due to the reservoir rock properties (shaley sand formation). A special fracturing and acidizing technique was required in order to allow the calculated kill rate of 40 bbl/ min. A low injection rate of 0.5 bbl/min with high injection pressure of 1,250 psi occurred due to a degree of formation damage and the mud cake covering the sand face. The calculated formation fracture pressure of 1,393 psi was a reliable value compared to actual fracture pressure of 1,400 psi. The designed killing rate of 40 bbl/ min could not reach the blowout well due to some leak-off of the injected fluid in unexpected directions of the induced fractures. Clearing PT-29 of all debris was very important for immediate well capping. The capping operation was done after the fire was extinguished; although the well was still flowing gas and water, no hazard of explosion was detected. The exact subsurface position of the blowout well of PT-29 was uncertain due to the lack of directional survey data. This problem reduced the effectiveness of the killing operation. A reliable water supply is important to the success of the killing job. Once the fracture had been induced, kill fluid had to be pumped continuously; any interruption might cause the fracture to heal. Deviation and directional survey data on every vertical or directional well are absolutely important for accurate relief well drilling purposes in case it is required.

  4. Interactions between plants and microorganisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Allelopathic microorganisms comprise rhizobacteria and fungi that colonize the surfaces of plant roots, and produce and release phytotoxic metabolites, similar to allelochemicals, that detrimentally affect growth of their host plants. The allelopathic microorganisms are grouped separately from typic...

  5. Kills Germs by the Millions!

    ERIC Educational Resources Information Center

    Swails, Molly

    1980-01-01

    Described is a science experiment involving the isolation and study of microorganisms. Bacteria from the mouth are cultured on blood agar culture plates and are then exposed to four different mouthwashes to test their effectiveness. (DS)

  6. Killing, letting die and euthanasia.

    PubMed

    Husak, D N

    1979-12-01

    Medical ethicists debate whether or not the moral assessment of cases of euthanasia should depend on whether the patient is 'killed' or 'allowed to die'. The usual presupposition is that a clear distinction between killing and letting die can be drawn so that this substantive question is not begged. I contend that the categorisation of cases of instances of killing rather than as instances of letting die depends in part on a prior moral assessment of the case. Hence is it trivially rather than substantively true that the distinction has moral significance. But even if a morally neutral (ie non-question begging) distinction could be drawn, its application to the euthanasia controversy is problematic. I illustrate the difficulties of employing this distinction to reach moral conclusions by critically discussing Philippa Foot's recent treatment of euthanasia. I conclude that even if an act of euthanasia is an instance of killing, and there exists a prima facie moral duty not to kill, and no more stringent duty overrides this duty, one still cannot determine such an act to be morally impermissible. PMID:541821

  7. Killing, letting die and euthanasia.

    PubMed Central

    Husak, D N

    1979-01-01

    Medical ethicists debate whether or not the moral assessment of cases of euthanasia should depend on whether the patient is 'killed' or 'allowed to die'. The usual presupposition is that a clear distinction between killing and letting die can be drawn so that this substantive question is not begged. I contend that the categorisation of cases of instances of killing rather than as instances of letting die depends in part on a prior moral assessment of the case. Hence is it trivially rather than substantively true that the distinction has moral significance. But even if a morally neutral (ie non-question begging) distinction could be drawn, its application to the euthanasia controversy is problematic. I illustrate the difficulties of employing this distinction to reach moral conclusions by critically discussing Philippa Foot's recent treatment of euthanasia. I conclude that even if an act of euthanasia is an instance of killing, and there exists a prima facie moral duty not to kill, and no more stringent duty overrides this duty, one still cannot determine such an act to be morally impermissible. PMID:541821

  8. Detecting the presence of microorganisms

    NASA Technical Reports Server (NTRS)

    Wilkins, Judd R. (Inventor); Stoner, Glenn E. (Inventor)

    1977-01-01

    The presence of microorganisms in a sample is determined by culturing microorganisms in a growth medium which is in contact with a measuring electrode and a reference electrode and detecting a change in potential between the electrodes caused by the presence of the microorganisms in the medium with a high impedance potentiometer.

  9. The Effect of Bacteriophage Preparations on Intracellular Killing of Bacteria by Phagocytes

    PubMed Central

    Jończyk-Matysiak, Ewa; Łusiak-Szelachowska, Marzanna; Kłak, Marlena; Bubak, Barbara; Międzybrodzki, Ryszard; Weber-Dąbrowska, Beata; Żaczek, Maciej; Fortuna, Wojciech; Rogóż, Paweł; Letkiewicz, Sławomir; Szufnarowski, Krzysztof; Górski, Andrzej

    2015-01-01

    Intracellular killing of bacteria is one of the fundamental mechanisms against invading pathogens. Impaired intracellular killing of bacteria by phagocytes may be the reason of chronic infections and may be caused by antibiotics or substances that can be produced by some bacteria. Therefore, it was of great practical importance to examine whether phage preparations may influence the process of phagocyte intracellular killing of bacteria. It may be important especially in the case of patients qualified for experimental phage therapy (approximately half of the patients with chronic bacterial infections have their immunity impaired). Our analysis included 51 patients with chronic Gram-negative and Gram-positive bacterial infections treated with phage preparations at the Phage Therapy Unit in Wroclaw. The aim of the study was to investigate the effect of experimental phage therapy on intracellular killing of bacteria by patients' peripheral blood monocytes and polymorphonuclear neutrophils. We observed that phage therapy does not reduce patients' phagocytes' ability to kill bacteria, and it does not affect the activity of phagocytes in patients with initially reduced ability to kill bacteria intracellularly. Our results suggest that experimental phage therapy has no significant adverse effects on the bactericidal properties of phagocytes, which confirms the safety of the therapy. PMID:26783541

  10. Microorganisms for producing organic acids

    SciTech Connect

    Pfleger, Brian Frederick; Begemann, Matthew Brett

    2014-09-30

    Organic acid-producing microorganisms and methods of using same. The organic acid-producing microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid, acrylic acid, propionic acid, lactic acid, and others. Further modifications to the microorganisms increase production of such organic acids as 3-hydroxypropionic acid, lactate, and others. Methods of producing such organic acids as 3-hydroxypropionic acid, lactate, and others with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers are also provided.

  11. Killing symmetries as Hamiltonian constraints

    NASA Astrophysics Data System (ADS)

    Lusanna, Luca

    2016-02-01

    The existence of a Killing symmetry in a gauge theory is equivalent to the addition of extra Hamiltonian constraints in its phase space formulation, which imply restrictions both on the Dirac observables (the gauge invariant physical degrees of freedom) and on the gauge freedom. When there is a time-like Killing vector field only pure gauge electromagnetic fields survive in Maxwell theory in Minkowski space-time, while in ADM canonical gravity in asymptotically Minkowskian space-times only inertial effects without gravitational waves survive.

  12. 33 CFR 117.801 - Newtown Creek, Dutch Kills, English Kills and their tributaries.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., English Kills and their tributaries. 117.801 Section 117.801 Navigation and Navigable Waters COAST GUARD....801 Newtown Creek, Dutch Kills, English Kills and their tributaries. (a) The following requirements apply to all bridges across Newtown Creek, Dutch Kills, English Kills, and their tributaries: (1)...

  13. Does Assessment Kill Student Creativity?

    ERIC Educational Resources Information Center

    Beghetto, Ronald A.

    2005-01-01

    Does assessment kill creativity? In this article, creativity is defined and discussed and an overview of creativity and motivational research is provided to describe how assessment practices can influence students' creativity. Recommendations for protecting creativity when assessing students also are provided.

  14. Phagocyte roulette in Salmonella killing.

    PubMed

    Fenlon, Luke A; Slauch, James M

    2014-01-15

    Salmonella propagates in macrophages to cause life-threatening infections, but the role of neutrophils in combating Salmonella has been controversial. In this issue, Burton et al. (2014) use single cell analyses and modeling to explain the ability of Salmonella to survive in macrophages while being killed by neutrophils. PMID:24439894

  15. Phagocyte Roulette in Salmonella Killing

    PubMed Central

    Fenlon, Luke A.; Slauch, James M.

    2014-01-01

    SUMMARY Salmonella propagate in macrophages to cause life-threatening infections, but the role of neutrophils in combating Salmonella has been controversial. In this issue, Burton et al. (2013) use single cell analyses and modeling to explain the ability of Salmonella to survive in macrophages, while being killed by neutrophils. PMID:24439894

  16. Farm Education at Stony Kill.

    ERIC Educational Resources Information Center

    Parisio, Richard

    1986-01-01

    Describes typical winter farm lessons for students visiting Stony Kill Farm Environmental Education Center located 70 miles north of New York City: butter and corncake making, soil erosion experiments, dissecting and growing seeds. Emphasizes major theme of conservation of farmland from destructive farming practices and careless development. (NEC)

  17. Quasilocal rotating conformal Killing horizons

    NASA Astrophysics Data System (ADS)

    Chatterjee, Ayan; Ghosh, Avirup

    2015-08-01

    The formulation of quasilocal conformal Killing horizons (CKH) is extended to include rotation. This necessitates that the horizon be foliated by 2-spheres which may be distorted. Matter degrees of freedom which fall through the horizon are represented by a real scalar field. We show that these rotating CKHs also admit a first law in differential form.

  18. Combined effects of lactoferrin and lysozyme on Streptococcus pneumoniae killing.

    PubMed

    André, G O; Politano, W R; Mirza, S; Converso, T R; Ferraz, L F C; Leite, L C C; Darrieux, M

    2015-12-01

    Streptococcus pneumoniae is a common colonizer of the human nasopharynx, which can occasionally spread to sterile sites, causing diseases such as otitis media, sinusitis, pneumonia, meningitis and bacteremia. Human apolactoferrin (ALF) and lysozyme (LZ) are two important components of the mucosal innate immune system, exhibiting lytic effects against a wide range of microorganisms. Since they are found in similar niches of the host, it has been proposed that ALF and LZ could act synergistically in controlling bacterial spread throughout the mucosa. The combination of ALF and LZ has been shown to enhance killing of different pathogens in vitro, with ALF facilitating the latter action of LZ. The aim of the present work was to investigate the combined effects of ALF and LZ on S pneumoniae. Concomitant addition of ALF and LZ had a synergistic killing effect on one of the pneumococci tested. Furthermore, the combination of ALF and ALZ was more bactericidal than lysozyme alone in all pneumococcal strains. Pneumococcal surface protein A (PspA), an important vaccine candidate, partially protects pneumococci from ALF mediated killing, while antibodies against one PspA enhance killing of the homologous strain by ALF. However, the serological variability of this molecule could limit the effect of anti-PspA antibodies on different pneumococci. Therefore, we investigated the ability of anti-PspA antibodies to increase ALF-mediated killing of strains that express different PspAs, and found that antisera to the N-terminal region of PspA were able to increase pneumococcal lysis by ALF, independently of the sequence similarities between the molecule expressed on the bacterial surface and that used to produce the antibodies. LF binding to the pneumococcal surface was confirmed by flow cytometry, and found to be inhibited in presence of anti-PspA antibodies. On a whole, the results suggest a contribution of ALF and LZ to pneumococcal clearance, and confirm PspA's ability to interact with ALF. PMID:26298002

  19. Biofilms: Survival Mechanisms of Clinically Relevant Microorganisms

    PubMed Central

    Donlan, Rodney M.; Costerton, J. William

    2002-01-01

    Though biofilms were first described by Antonie van Leeuwenhoek, the theory describing the biofilm process was not developed until 1978. We now understand that biofilms are universal, occurring in aquatic and industrial water systems as well as a large number of environments and medical devices relevant for public health. Using tools such as the scanning electron microscope and, more recently, the confocal laser scanning microscope, biofilm researchers now understand that biofilms are not unstructured, homogeneous deposits of cells and accumulated slime, but complex communities of surface-associated cells enclosed in a polymer matrix containing open water channels. Further studies have shown that the biofilm phenotype can be described in terms of the genes expressed by biofilm-associated cells. Microorganisms growing in a biofilm are highly resistant to antimicrobial agents by one or more mechanisms. Biofilm-associated microorganisms have been shown to be associated with several human diseases, such as native valve endocarditis and cystic fibrosis, and to colonize a wide variety of medical devices. Though epidemiologic evidence points to biofilms as a source of several infectious diseases, the exact mechanisms by which biofilm-associated microorganisms elicit disease are poorly understood. Detachment of cells or cell aggregates, production of endotoxin, increased resistance to the host immune system, and provision of a niche for the generation of resistant organisms are all biofilm processes which could initiate the disease process. Effective strategies to prevent or control biofilms on medical devices must take into consideration the unique and tenacious nature of biofilms. Current intervention strategies are designed to prevent initial device colonization, minimize microbial cell attachment to the device, penetrate the biofilm matrix and kill the associated cells, or remove the device from the patient. In the future, treatments may be based on inhibition of genes involved in cell attachment and biofilm formation. PMID:11932229

  20. Proteolysis in hyperthermophilic microorganisms

    DOE PAGESBeta

    Ward, Donald E.; Shockley, Keith R.; Chang, Lara S.; Levy, Ryan D.; Michel, Joshua K.; Conners, Shannon B.; Kelly, Robert M.

    2002-01-01

    Proteases are found in every cell, where they recognize and break down unneeded or abnormal polypeptides or peptide-based nutrients within or outside the cell. Genome sequence data can be used to compare proteolytic enzyme inventories of different organisms as they relate to physiological needs for protein modification and hydrolysis. In this review, we exploit genome sequence data to compare hyperthermophilic microorganisms from the euryarchaeotal genus Pyrococcus , the crenarchaeote Sulfolobus solfataricus , and the bacterium Thermotoga maritima . An overview of the proteases in these organisms is given based on those proteases that have been characterized and on putativemore » proteases that have been identified from genomic sequences, but have yet to be characterized. The analysis revealed both similarities and differences in the mechanisms utilized for proteolysis by each of these hyperthermophiles and indicated how these mechanisms relate to proteolysis in less thermophilic cells and organisms.« less

  1. Proteolysis in hyperthermophilic microorganisms

    PubMed Central

    Ward, Donald E.; Shockley, Keith R.; Chang, Lara S.; Levy, Ryan D.; Michel, Joshua K.; Conners, Shannon B.; Kelly, Robert M.

    2002-01-01

    Proteases are found in every cell, where they recognize and break down unneeded or abnormal polypeptides or peptide-based nutrients within or outside the cell. Genome sequence data can be used to compare proteolytic enzyme inventories of different organisms as they relate to physiological needs for protein modification and hydrolysis. In this review, we exploit genome sequence data to compare hyperthermophilic microorganisms from the euryarchaeotal genus Pyrococcus, the crenarchaeote Sulfolobus solfataricus, and the bacterium Thermotoga maritima. An overview of the proteases in these organisms is given based on those proteases that have been characterized and on putative proteases that have been identified from genomic sequences, but have yet to be characterized. The analysis revealed both similarities and differences in the mechanisms utilized for proteolysis by each of these hyperthermophiles and indicated how these mechanisms relate to proteolysis in less thermophilic cells and organisms. PMID:15803660

  2. Gravitaxis in unicellular microorganisms

    NASA Astrophysics Data System (ADS)

    Häder, D.-P.

    1999-01-01

    Orientation of organisms with respect to the gravitational field of the Earth has been studied for more than 100 years in a number of unicellular microorganisms including flagellates and ciliates. Several hypotheses have been developed how the weak stimulus is perceived. Intracellular statoliths have been found to be involved in gravitaxis of Loxodes, while no specialized organelles have been detected in other ciliates, e.g. Paramecium. Also in the slime mold Physarum no specialized gravireceptors have been identified yet. In the flagellate Euglena gracilis the whole cell body, which is denser than the surrounding medium, seems to act as a statolith pressing onto the lower membrane where it activates mechanosensitive ion channels. Similar results were obtained for the ciliate Paramecium. In contrast to the flagellate Euglena, several ciliates have been found to show gravikinesis, which is defined as a dependence of the swimming velocity on the direction of movement in the gravity field.

  3. Beetle Kill Wall at NREL

    SciTech Connect

    2010-01-01

    When it comes to designing an interior decorative feature for one of the most energy efficient office buildings in the world, very few would consider bringing in a beetle to do the job. But thats what happened at the U.S. Department of Energy's (DOE) Research Support Facility (RSF) located on the National Renewable Energy Laboratory (NREL) campus.In June, the RSF will become home to more than 800 workers from DOE and NREL and building visitors will be greeted with a soaring, two-story high wall entirely covered with wood harvested from the bark beetle infestation that has killed millions of pine trees in the Western U.S. But, the use of beetle kill wood is just one example of the resources being leveraged to make the RSF a model for sustainability and one more step toward NRELs goal to be a net zero energy campus.

  4. Beetle Kill Wall at NREL

    ScienceCinema

    None

    2013-05-29

    When it comes to designing an interior decorative feature for one of the most energy efficient office buildings in the world, very few would consider bringing in a beetle to do the job. But thats what happened at the U.S. Department of Energy's (DOE) Research Support Facility (RSF) located on the National Renewable Energy Laboratory (NREL) campus.In June, the RSF will become home to more than 800 workers from DOE and NREL and building visitors will be greeted with a soaring, two-story high wall entirely covered with wood harvested from the bark beetle infestation that has killed millions of pine trees in the Western U.S. But, the use of beetle kill wood is just one example of the resources being leveraged to make the RSF a model for sustainability and one more step toward NRELs goal to be a net zero energy campus.

  5. Traits of Heracleum sosnowskyi Plants in Monostand on Invaded Area

    PubMed Central

    2015-01-01

    The ability of giant hogweeds to form monodominant communities and even pure monostands in invaded areas has been well documented. Understanding of the mechanisms leading to monostand formation can aid in determining the limitations of existing community ecology models and establishing an effective management plan for invasive species elimination. The aim of this observational study was to investigate traits of Heracleum sosnowskyi plants (demography, canopy structure, morphology and physiology) of the plants in a pure stand in an invaded area useful for understanding potential monostand formation mechanisms. All measurements were performed in one typical Heracleum sosnowskyi monostand located in an abandoned agriculture field located in Syktyvkar city suburb (North-east Russia). This monostand consisted of five main plant growth stages: seed, seedling, juvenile, vegetative adult, and generative adult. Plants of all stages began to grow simultaneously shortly after the snowmelt, at the same time as spring ephemeral plant species grew. The density of generative plants did not change during the vegetation period, but the density of the other plant stages rapidly decreased after the formation of a tall (up to 2–2.5 m) and dense (Leaf area index up to 6.5) canopy. The canopy captured approximately 97% of the light. H. sosnowskyi showed high (several orders of magnitude higher than average taiga zone grasses) photosynthetic water use efficiency (6–7 μM CO2/μM H2O). Formation of H. sosnowskyi monostands occurs primarily in disturbed areas with relatively rich and well-moistened soils. Early commencement of growth, rapid formation of a dense canopy, high efficiency of light and water use during photosynthesis, ability of young plants to survive in low light conditions, rapid recovery of above-ground plant parts after damage, and the high density of the soil seed bank are the most important traits of H. sosnowskyi plants for monostand formation in invaded areas. PMID:26565793

  6. Traits of Heracleum sosnowskyi Plants in Monostand on Invaded Area.

    PubMed

    Dalke, Igor V; Chadin, Ivan F; Zakhozhiy, Ilya G; Malyshev, Ruslan V; Maslova, Svetlana P; Tabalenkova, Galina N; Golovko, Tamara K

    2015-01-01

    The ability of giant hogweeds to form monodominant communities and even pure monostands in invaded areas has been well documented. Understanding of the mechanisms leading to monostand formation can aid in determining the limitations of existing community ecology models and establishing an effective management plan for invasive species elimination. The aim of this observational study was to investigate traits of Heracleum sosnowskyi plants (demography, canopy structure, morphology and physiology) of the plants in a pure stand in an invaded area useful for understanding potential monostand formation mechanisms. All measurements were performed in one typical Heracleum sosnowskyi monostand located in an abandoned agriculture field located in Syktyvkar city suburb (North-east Russia). This monostand consisted of five main plant growth stages: seed, seedling, juvenile, vegetative adult, and generative adult. Plants of all stages began to grow simultaneously shortly after the snowmelt, at the same time as spring ephemeral plant species grew. The density of generative plants did not change during the vegetation period, but the density of the other plant stages rapidly decreased after the formation of a tall (up to 2-2.5 m) and dense (Leaf area index up to 6.5) canopy. The canopy captured approximately 97% of the light. H. sosnowskyi showed high (several orders of magnitude higher than average taiga zone grasses) photosynthetic water use efficiency (6-7 μM CO2/μM H2O). Formation of H. sosnowskyi monostands occurs primarily in disturbed areas with relatively rich and well-moistened soils. Early commencement of growth, rapid formation of a dense canopy, high efficiency of light and water use during photosynthesis, ability of young plants to survive in low light conditions, rapid recovery of above-ground plant parts after damage, and the high density of the soil seed bank are the most important traits of H. sosnowskyi plants for monostand formation in invaded areas. PMID:26565793

  7. Unfolding the resident-invader dynamics of similar strategies.

    PubMed

    Dercole, Fabio; Geritz, Stefan A H

    2016-04-01

    We investigate the competition between two groups of similar agents in the restricted, but classical context of unstructured populations varying in continuous time in an isolated, homogeneous, and constant abiotic environment. Individual behavioral and phenotypic traits are quantified by one-dimensional strategies and intra- as well as inter-specific interactions are described in the vicinity of a stationary regime. Some known results are revisited: invasion by a new strategy generically implies the substitution of the former resident; and resident-invader coexistence is possible close to singular strategies-the stationary points of the invasion fitness-and is generically protected-each of the two competing groups can invade the other. An (almost known) old conjecture is shown true: competition close to a singular strategy is "essentially Lotka-Volterra"-dominance of one strategy, protected coexistence at an intermediate equilibrium, and mutual exclusion are the generic outcomes. And the unfolding of the competition scenarios is completed with the analysis of three degenerate singular strategies-characterized by vanishing second-order fitness derivatives-near which resident-invader coexistence can be unprotected. Our approach is based on the series expansion of a generic demographic model, w.r.t. the small strategy difference between the two competing groups, and on known results on time-scale separation and bifurcation theories. The analysis is carried out up to third order and is extendable to any order. For each order, explicit genericity conditions under which higher orders can be neglected are derived and, interestingly, they are known prior to invasion. An important result is that degeneracies up to third-order are required to have more than one stable way of coexistence. Such degeneracies can be due to particular symmetries in the model formulation, and breaking the genericity conditions provides a direct way to draw biological interpretations. The developed body of theory is exemplified on a model for the evolution of cannibalism and on Lotka-Volterra competition models. PMID:26723534

  8. Polysaccharides from Extremophilic Microorganisms

    NASA Astrophysics Data System (ADS)

    Nicolaus, B.; Moriello, V. Schiano; Lama, L.; Poli, A.; Gambacorta, A.

    2004-02-01

    Several marine thermophilic strains were analyzed for exopolysaccharide production. The screening process revealed that a significant number of thermophilic microorganisms were able to produce biopolymers, and some of them also revealed interesting chemical compositions. We have identified four new polysaccharides from thermophilic marine bacteria, with complex primary structures and with different repetitive units: a galacto-mannane type from strain number 4004 and mannane type for the other strains. The thermophilic Bacillus thermantarcticus produces two exocellular polysaccharides (EPS 1, EPS 2) that give the colonies a typical mucous character. The exopolysaccharide fraction was produced with all substrates assayed, although a higher yield 400 mg liter-1 was obtained with mannose as carbon and energy source. NMR spectra confirmed that EPS 1 was a heteropolysaccharide of which the repeating unit was constituted by four different α-D-mannoses and three different β-D-glucoses. It seems to be close to some xantan polymers. EPS 2 was a mannan. Four different α-D-mannoses were found as the repeating unit. Production and chemical studies of biopolymers produced by halophilic archaea, Haloarcula species were also reported.

  9. 33 CFR 117.801 - Newtown Creek, Dutch Kills, English Kills and their tributaries.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Newtown Creek, Dutch Kills, English Kills and their tributaries. 117.801 Section 117.801 Navigation and Navigable Waters COAST GUARD....801 Newtown Creek, Dutch Kills, English Kills and their tributaries. (a) The following...

  10. 33 CFR 117.801 - Newtown Creek, Dutch Kills, English Kills and their tributaries.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Newtown Creek, Dutch Kills, English Kills and their tributaries. 117.801 Section 117.801 Navigation and Navigable Waters COAST GUARD....801 Newtown Creek, Dutch Kills, English Kills and their tributaries. (a) The following...

  11. 33 CFR 117.801 - Newtown Creek, Dutch Kills, English Kills and their tributaries.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Newtown Creek, Dutch Kills, English Kills and their tributaries. 117.801 Section 117.801 Navigation and Navigable Waters COAST GUARD....801 Newtown Creek, Dutch Kills, English Kills and their tributaries. (a) The following...

  12. Interaction of Species Traits and Environmental Disturbance Predicts Invasion Success of Aquatic Microorganisms

    PubMed Central

    Mächler, Elvira; Altermatt, Florian

    2012-01-01

    Factors such as increased mobility of humans, global trade and climate change are affecting the range of many species, and cause large-scale translocations of species beyond their native range. Many introduced species have a strong negative influence on the new local environment and lead to high economic costs. There is a strong interest to understand why some species are successful in invading new environments and others not. Most of our understanding and generalizations thereof, however, are based on studies of plants and animals, and little is known on invasion processes of microorganisms. We conducted a microcosm experiment to understand factors promoting the success of biological invasions of aquatic microorganisms. In a controlled lab experiment, protist and rotifer species originally isolated in North America invaded into a natural, field-collected community of microorganisms of European origin. To identify the importance of environmental disturbances on invasion success, we either repeatedly disturbed the local patches, or kept them as undisturbed controls. We measured both short-term establishment and long-term invasion success, and correlated it with species-specific life-history traits. We found that environmental disturbances significantly affected invasion success. Depending on the invading species’ identity, disturbances were either promoting or decreasing invasion success. The interaction between habitat disturbance and species identity was especially pronounced for long-term invasion success. Growth rate was the most important trait promoting invasion success, especially when the species invaded into a disturbed local community. We conclude that neither species traits nor environmental factors alone conclusively predict invasion success, but an integration of both of them is necessary. PMID:23028985

  13. Killing-Yano tensors in spaces admitting a hypersurface orthogonal Killing vector

    NASA Astrophysics Data System (ADS)

    Garfinkle, David; Glass, E. N.

    2013-03-01

    Methods are presented for finding Killing-Yano tensors, conformal Killing-Yano tensors, and conformal Killing vectors in spacetimes with a hypersurface orthogonal Killing vector. These methods are similar to a method developed by the authors for finding Killing tensors. In all cases one decomposes both the tensor and the equation it satisfies into pieces along the Killing vector and pieces orthogonal to the Killing vector. Solving the separate equations that result from this decomposition requires less computing than integrating the original equation. In each case, examples are given to illustrate the method.

  14. Laser Microbial Killing and Biofilm Disruption

    NASA Astrophysics Data System (ADS)

    Krespi, Yosef P.; Kizhner, Victor

    2009-06-01

    Objectives: To analyze the ability of NIR lasers to reduce bacterial load and demonstrate the capability of fiber-based Q-switched Nd:YAG laser disrupting biofilm. Study Design: NIR diode laser was tested in vitro and in vivo using pathogenic microorganisms (S. aureus, S. pneumoniae, P. aeruginosa). In addition biofilms were grown from clinical Pseudomonas isolates and placed in culture plates, screws, tympanostomy tubes and PET sutures. Methods: In the animal experiments acute rhinosinusitis model was created by packing the rabbit nose with bacteria soaked solution. The nasal pack was removed in two days and nose was exposed to laser irradiation. A 940 nm diode laser with fiber diffuser was used. Nasal cultures were obtained before and after the laser treatments. Animals were sacrificed fifteen days following laser treatment and bacteriologic/histologic results analyzed. Q-switched Nd:YAG laser generated shockwave pulses were delivered on biofilm using special probes over culture plates, screws, tubes, and PET sutures for the biofilm experiments. Results: Average of two log bacteria reduction was achieved with NIR laser compared to controls. Histologic studies demonstrated preservation of tissue integrity without significant damage to mucosa. Biofilms were imaged before, during and after treatment using a confocal microscope. During laser-generated shockwave application, biofilm was initially seen to oscillate and eventually break off. Large and small pieces of biofilm were totally and instantly removed from the surface to which they were attached in seconds. Conclusions: Significant bacterial reduction was achieved with NIR laser therapy in this experimental in vitro and animal study. In addition we disrupted Pseudomonas aeruginosa biofilms using Q-switched Nd:YAG laser and special probes generating plasma and shockwave. This new and innovative method of bacteria killing and biofilm disruption without injuring host tissue may have clinical application in the future.

  15. Effects of a Major Tree Invader on Urban Woodland Arthropods

    PubMed Central

    2015-01-01

    Biological invasions are a major threat to biodiversity; however, the degree of impact can vary depending on the ecosystem and taxa. Here, we test whether a top invader at a global scale, the tree Robinia pseudoacacia (black locust or false acacia), which is known to profoundly change site conditions, significantly affects urban animal diversity. As a first multi-taxon study of this kind, we analyzed the effects of Robinia dominance on 18 arthropod taxa by pairwise comparisons of woodlands in Berlin, Germany, that were dominated by R. pseudoacacia or the native pioneer tree Betula pendula. As a negative effect, abundances of five arthropod taxa decreased (Chilopoda, Formicidae, Diptera, Heteroptera, Hymenoptera); 13 others were not affected. Woodland type affected species composition of carabids and functional groups in spiders, but surprisingly did not decrease alpha and beta diversity of carabid and spider assemblages or the number of endangered species. Tree invasion thus did not induce biotic homogenization at the habitat scale. We detected no positive effects of alien dominance. Our results illustrate that invasions by a major tree invader can induce species turnover in ground-dwelling arthropods, but do not necessarily reduce arthropod species abundances or diversity and might thus contribute to the conservation of epigeal invertebrates in urban settings. Considering the context of invasion impacts thus helps to set priorities in managing biological invasions and can illustrate the potential of novel ecosystems to maintain urban biodiversity. PMID:26359665

  16. Toxicity to rats of corn invaded by Chaetomium globosum.

    PubMed

    Christensen, C M; Nelson, G H; Mirocha, C J; Bates, F; Dorworth, C E

    1966-09-01

    Of 53 isolates of Chaetomium globosum Kunze isolated from corn, manufactured feed, and fiberboard, grown on autoclaved corn, and fed to rats, 25 were lethal within 4 to 6 days. Thirty-six single ascospore cultures of one isolate were uniformly lethal when similarly grown and fed to rats. Incubation of the fungus on corn for 6 to 8 weeks resulted in greater toxicity than shorter incubation times. Premortem symptoms indicated damage to the central nervous system of the affected animals, and postmortem lesions included hemoglobinuria, hemorrhagic enteritis, and subdural hemorrhaging. Corn invaded by C. globosum and toxic to rats had no detectable effects on swine when fed as their sole ration for 6 weeks, and appeared to be consumed with relish. The toxic substance was best obtained by defatting the fungus-invaded corn with petroleum ether (bp, 60 to 70 C), extraction with acetone, and further purification by elution from a silica gel column with acetone and 5% acetone in chloroform. PMID:5970465

  17. Exotic invaders gain foraging benefits by shoaling with native fish

    PubMed Central

    Camacho-Cervantes, Morelia; Garcia, Constantino Macías; Ojanguren, Alfredo F.; Magurran, Anne E.

    2014-01-01

    Freshwater habitats are under increasing threat due to invasions of exotic fish. These invasions typically begin with the introduction of small numbers of individuals unfamiliar with the new habitat. One way in which the invaders might overcome this disadvantage is by associating with native taxa occupying a similar ecological niche. Here we used guppies (Poecilia reticulata) from a feral population in Mexico to test the prediction that exotic shoaling fish can associate with heterospecifics, and that they improve their foraging efficiency by doing so. Guppies have invaded the Mexican High Plateau and are implicated in the declines of many native topminnow (Goodeinae) species. We show that heterospecific associations between guppies and topminnows can deliver the same foraging benefits as conspecific shoals, and that variation in foraging gains is linked to differences in association tendency. These results uncover a mechanism enabling founding individuals to survive during the most vulnerable phase of an invasion and help explain why guppies have established viable populations in many parts of Mexico as well in every continent except Antarctica. PMID:26064552

  18. Nasal cavity epithelioid hemangioendothelioma invading the anterior skull base

    PubMed Central

    Ogita, Shogo; Endo, Toshiki; Nomura, Kazuhiro; Ogawa, Takenori; Watanabe, Mika; Higashi, Kenjiro; Katori, Yukio; Tominaga, Teiji

    2016-01-01

    Background: Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor that frequently occurs in soft tissues. Patients suffer from local recurrence and remote metastasis because of its malignant potential. Here, we present a rare case of EHE that originated from nasal cavity and invaded intracranially through the anterior skull base. Case Description: This is a 27-year-old woman who presented a local physician with intermittent epistaxis and a facial pain around her nose. Preoperative studies demonstrated that the tumor invaded into anterior skull base and the dura matter. Therefore, we performed combined skull base and transnasal surgery, which achieved complete resection of the tumor. Postoperative course of the patient was uneventful. No recurrence or distant metastasis was observed in the patient for 2 years following the radical resection. Conclusions: To date, four cases of EHE in the nasal cavity were reported. This is the first case in which EHE demonstrated invasive potentials with intracranial extension. Radical surgical resection plays an important role for better management of invasive paranasal EHE. PMID:27213107

  19. Effects of a Major Tree Invader on Urban Woodland Arthropods.

    PubMed

    Buchholz, Sascha; Tietze, Hedwig; Kowarik, Ingo; Schirmel, Jens

    2015-01-01

    Biological invasions are a major threat to biodiversity; however, the degree of impact can vary depending on the ecosystem and taxa. Here, we test whether a top invader at a global scale, the tree Robinia pseudoacacia (black locust or false acacia), which is known to profoundly change site conditions, significantly affects urban animal diversity. As a first multi-taxon study of this kind, we analyzed the effects of Robinia dominance on 18 arthropod taxa by pairwise comparisons of woodlands in Berlin, Germany, that were dominated by R. pseudoacacia or the native pioneer tree Betula pendula. As a negative effect, abundances of five arthropod taxa decreased (Chilopoda, Formicidae, Diptera, Heteroptera, Hymenoptera); 13 others were not affected. Woodland type affected species composition of carabids and functional groups in spiders, but surprisingly did not decrease alpha and beta diversity of carabid and spider assemblages or the number of endangered species. Tree invasion thus did not induce biotic homogenization at the habitat scale. We detected no positive effects of alien dominance. Our results illustrate that invasions by a major tree invader can induce species turnover in ground-dwelling arthropods, but do not necessarily reduce arthropod species abundances or diversity and might thus contribute to the conservation of epigeal invertebrates in urban settings. Considering the context of invasion impacts thus helps to set priorities in managing biological invasions and can illustrate the potential of novel ecosystems to maintain urban biodiversity. PMID:26359665

  20. Killing(-Yano) tensors in string theory

    NASA Astrophysics Data System (ADS)

    Chervonyi, Yuri; Lunin, Oleg

    2015-09-01

    We construct the Killing(-Yano) tensors for a large class of charged black holes in higher dimensions and study general properties of such tensors, in particular, their behavior under string dualities. Killing(-Yano) tensors encode the symmetries beyond isometries, which lead to insights into dynamics of particles and fields on a given geometry by providing a set of conserved quantities. By analyzing the eigenvalues of the Killing tensor, we provide a prescription for constructing several conserved quantities starting from a single object, and we demonstrate that Killing tensors in higher dimensions are always associated with ellipsoidal coordinates. We also determine the transformations of the Killing(-Yano) tensors under string dualities, and find the unique modification of the Killing-Yano equation consistent with these symmetries. These results are used to construct the explicit form of the Killing(-Yano) tensors for the Myers-Perry black hole in arbitrary number of dimensions and for its charged version.

  1. 40 CFR 725.420 - Recipient microorganisms.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Recipient microorganisms. 725.420... CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS General Exemptions for New Microorganisms § 725.420 Recipient microorganisms. The following recipient microorganisms are eligible for...

  2. 40 CFR 725.420 - Recipient microorganisms.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Recipient microorganisms. 725.420... CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS General Exemptions for New Microorganisms § 725.420 Recipient microorganisms. The following recipient microorganisms are eligible for...

  3. On the Isolation of Halophilic Microorganisms from Salt Deposits of Great Geological Age

    NASA Technical Reports Server (NTRS)

    Stan-Lotter, Helga; Denner, Ewald; Orans, Robin (Editor)

    1993-01-01

    From salt sediments of Triassic or Permian ace from various locations in the world halophilic microorganisms were isolated. Molecular characteristics of several of the isolates suggested they belong to the archaebacteriae. One group appears to represent novel strains; several properties or one such isolate, strain BIp, are described here. The existence of viable microorganisms in ancient sediments would have great implications with respect to our notions on evolution, the search for life in extraterrestrial environments and the long- term survival of functional biological structures. Of crucial importance is thus the question if these microorganisms existed in the salt since the time of deposition or invaded at some later date. Some suggestions to address these issues experimentally are discussed.

  4. On the isolation of halophilic microorganisms from salt deposits of great geological age

    NASA Technical Reports Server (NTRS)

    Stan-Lotter, Helga; Denner, Ewald

    1993-01-01

    From salt sediments of Triassic or Permian age from various locations in the world halophilic microorganisms were isolated. Molecular characteristics of several of the isolates suggested they belong to the archaebacteria. One group appears to represent novel strains; several properties of one such isolate, strain BIp, are described here. The existence of viable microorganisms in ancient sediment would have great implications with respect to our notions on evolution, the research for life in extraterrestrial environments, and the longterm survival of functional biological structures. Of crucial importance is thus the question if these microorganisms existed in the salt since the time of deposition or invaded at some later date. Some suggestions to address these issues experimentally are discussed.

  5. Fish kill from underwater explosions

    USGS Publications Warehouse

    Stuart, David J.

    1962-01-01

    The U.S. Geological Survey has used 23 different shotpoints during two seasons of field work in our seismic study of crustal structure in western United States. Without exception, it has been found that under-water shotpoints result in a more efficient conversion of explosive energy into seismic energy than do drilled-hole shotpoints. This experience, together with elimination of drilling costs, has led to the use of underwater shotpoints wherever possible. Three of the 23 shotpoints were in the Pacific Ocean, and for these we have no detailed information on the fish kill. Another six shotpoints were located in inland bodies of water. These are: * Soda Lake near Fallon, Nevada * Mono Lake near Lee Vining, California * Lake Mead near Boulder City, Nevada * Shasta Lake near Redding, California * C.J. Strike Reservoir near Bruneau, Idaho * Lucky Peak Reservoir near Boise, Idaho The 22 high-explosive charges, weighing a total of 95,100 pounds, that were fired in lakes containing fish life resulted in the known death of 2,413 game fish with a total weight of 759 pounds. The average mortality was 110 game fish or 34.5 pounds of game fish killed per average shot of 4,325 pounds of high-explosives.

  6. EFFICACY OF OZONE IN KILLING LISTERIA MONOCYTOGENES ON ALFALFA SEEDS AND SPROUTS, AND EFFECTS ON SENSORY QUALITY OF SPROUTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was done to determine the efficacy of aqueous ozone treatment in killing Listeria monocytogenes on inoculated alfalfa seeds and sprouts. Reduction in populations of naturally occurring aerobic microorganisms on sprouts and changes in sensory quality of sprouts were also determined. Treatme...

  7. Effect of nitric oxide on staphylococcal killing and interactive effect with superoxide.

    PubMed Central

    Kaplan, S S; Lancaster, J R; Basford, R E; Simmons, R L

    1996-01-01

    The role of reactive nitrogen intermediates (RNI) such as nitric oxide (.NO) in host defense against pyogenic microorganisms is unclear, and the actual interactive effect of RNI and reactive oxidative intermediates (ROI) for microbial killing has not been determined. Since, in nature, ROI and RNI might be generated together within any local infection, we evaluated the separate and interactive effects of .NO and O2- on staphylococcal survival by using a simplified system devoid of eukaryotic cells. These studies showed that prolonged exposure of staphylococci to .NO does not result in early loss of viability but instead is associated with a dose-related delayed loss of viability. This effect is abrogated by the presence of hemoglobin, providing further evidence that the effect is RNI associated. Superoxide-mediated killing also is dose related, but in contrast to RNI-mediated killing, it is rapid and occurs within 2 h of exposure. We further show that the interaction of .NO and O(2)- results in decreased O(2)--mediated staphylococcal killing at early time points. .NO, however, appears to enhance or stabilize microbial killing over prolonged periods of incubation. This study did not produce evidence of early synergism of ROI and RNI, but it does suggest that .NO may contribute to host defense, especially when ROI-mediated killing is compromised. PMID:8557376

  8. Group II Introns: Mobile Ribozymes that Invade DNA

    PubMed Central

    Lambowitz, Alan M.; Zimmerly, Steven

    2011-01-01

    SUMMARY Group II introns are mobile ribozymes that self-splice from precursor RNAs to yield excised intron lariat RNAs, which then invade new genomic DNA sites by reverse splicing. The introns encode a reverse transcriptase that stabilizes the catalytically active RNA structure for forward and reverse splicing, and afterwards converts the integrated intron RNA back into DNA. The characteristics of group II introns suggest that they or their close relatives were evolutionary ancestors of spliceosomal introns, the spliceosome, and retrotransposons in eukaryotes. Further, their ribozyme-based DNA integration mechanism enabled the development of group II introns into gene targeting vectors (targetrons), which have the unique feature of readily programmable DNA target specificity. PMID:20463000

  9. Mature ovarian dermoid cyst invading the urinary bladder.

    PubMed

    Tandon, A; Gulleria, K; Gupta, S; Goel, S; Bhargava, S K; Vaid, N B

    2010-06-01

    Mature ovarian dermoid cysts are common lesions, accounting for up to 10-25% of all ovarian neoplasms. Uncomplicated dermoid cysts are often asymptomatic and are relatively easy to diagnose on imaging and to treat. Symptoms develop once complications set in and these may cause diagnostic dilemmas. Torsion (16%) is the most common complication, while rupture, suppuration and malignant transformation are relatively uncommon. Of all these complications, spontaneous rupture into the urinary bladder is least common. The diagnosis of this condition has been through the use of cystoscopy or laparotomy in all cases reported so far. We report a case of a 30-year-old patient with pyuria and dysuria, where ultrasound examination clearly demonstrated an ovarian dermoid cyst invading the urinary bladder. A clear-cut imaging diagnosis helped to allow planning of surgery in advance and a mucosa-sparing partial bladder resection could be performed. PMID:20069670

  10. Stroke Caused by Lung Cancer Invading the Left Atrium.

    PubMed

    Dimitrović, Ana; Breitenfeld, Tomislav; Supanc, Višnja; Roje-Bedeković, Marina; Butković Soldo, Silva; Vargek-Solter, Vesna

    2016-05-01

    We describe a 59-year-old stroke patient presented with sudden onset left side weakness and a speech disorder due to a major acute cerebral infarction in the area of the right middle cerebral artery, right posterior cerebral artery, and small infarctions in the area of the left middle and left posterior cerebral artery. For the previous month, the patient had been feeling weak and had no appetite. The patient had not been previously seriously ill. A chest x-ray showed a large mass in the upper zone of the right lung. Chest computed tomography scan and echocardiography were performed and revealed advanced lung cancer invading the left atrium. Spontaneous tumor embolism is a rare cause of stroke and should be considered in the differential diagnosis of stroke in a cancer patient. Also, sometimes stroke can be the first manifestation of advanced cancer. PMID:26922131

  11. How rhizobial symbionts invade plants: the SinorhizobiumMedicago model

    PubMed Central

    Jones, Kathryn M.; Kobayashi, Hajime; Davies, Bryan W.; Taga, Michiko E.; Walker, Graham C.

    2009-01-01

    Nitrogen-fixing rhizobial bacteria and leguminous plants have evolved complex signal exchange mechanisms that allow a specific bacterial species to induce its host plant to form invasion structures through which the bacteria can enter the plant root. Once the bacteria have been endocytosed within a host-membrane-bound compartment by root cells, the bacteria differentiate into a new form that can convert atmospheric nitrogen into ammonia. Bacterial differentiation and nitrogen fixation are dependent on the microaerobic environment and other support factors provided by the plant. In return, the plant receives nitrogen from the bacteria, which allows it to grow in the absence of an external nitrogen source. Here, we review recent discoveries about the mutual recognition process that allows the model rhizobial symbiont Sinorhizobium meliloti to invade and differentiate inside its host plant alfalfa (Medicago sativa) and the model host plant barrel medic (Medicago truncatula). PMID:17632573

  12. Sensor arrays for detecting microorganisms

    NASA Technical Reports Server (NTRS)

    Lewis, Nathan S. (Inventor); Freund, Michael S. (Inventor)

    2000-01-01

    A sensor array for detecting a microorganism comprising first and second sensors electrically connected to an electrical measuring apparatus, wherein the sensors comprise a region of nonconducting organic material and a region of conducting material compositionally that is different than the nonconducting organic material and an electrical path through the regions of nonconducting organic material and the conducting material. A system for identifying microorganisms using the sensor array, a computer and a pattern recognition algorithm, such as a neural net are also disclosed.

  13. Constraints on coastal dune invasion for a notorious plant invader

    PubMed Central

    Griffith, Alden B.; Ahmed, Tania; Hildner, Abigail L. G.; Kuckreja, Shivani; Long, Shuangxou

    2015-01-01

    Although most biological invasions are not successful, relatively few studies have examined otherwise notorious invaders in systems where they are not highly problematic. The annual grass Bromus tectorum is a dominant invader in western North America, but is usually confined to human-dominated and disturbed systems (e.g. roadsides and parking lots) in the East where it remains virtually unstudied. This study aims to address fundamental ecological questions regarding B. tectorum in a Cape Cod dune ecosystem. (i) What is the range of variation in population dynamics and the potential for population growth? (ii) Which factors influence its local abundance and distribution? We observed substantial variation in population dynamics over 3 years, with the number of adult B. tectorum individuals increasing substantially between the first 2 years (λ = 9.24) and then decreasing (λ = 0.43). Population growth in terms of total seeds was similarly variable, but to a lesser extent (λ = 2.32 followed by λ = 0.32). Experimental soil disturbance led to a more than 10-fold increase in mean seedling emergence, and high sensitivity to differences in emergence carried this effect through the life cycle. In contrast, barriers to seed dispersal had no effect on population dynamics, suggesting limited dispersal in this system. Across the landscape, the presence of B. tectorum was associated with areas of higher plant diversity as opposed to those with a strong dominant (e.g. the foredune, dominated by Ammophila breviligulata, or low heathlands, characterized by Hudsonia tomentosa and Arctostaphylos uva-ursi). Overall, we find that B. tectorum is capable of both substantial population growth and decline in a dune ecosystem, but is likely limited without disturbance and dispersal agents. Thus, management actions that restrict dune access (e.g. for nesting habitat) likely have the co-benefit of limiting the invasive potential of B. tectorum. PMID:26558705

  14. Constraints on coastal dune invasion for a notorious plant invader.

    PubMed

    Griffith, Alden B; Ahmed, Tania; Hildner, Abigail L G; Kuckreja, Shivani; Long, Shuangxou

    2015-01-01

    Although most biological invasions are not successful, relatively few studies have examined otherwise notorious invaders in systems where they are not highly problematic. The annual grass Bromus tectorum is a dominant invader in western North America, but is usually confined to human-dominated and disturbed systems (e.g. roadsides and parking lots) in the East where it remains virtually unstudied. This study aims to address fundamental ecological questions regarding B. tectorum in a Cape Cod dune ecosystem. (i) What is the range of variation in population dynamics and the potential for population growth? (ii) Which factors influence its local abundance and distribution? We observed substantial variation in population dynamics over 3 years, with the number of adult B. tectorum individuals increasing substantially between the first 2 years (λ = 9.24) and then decreasing (λ = 0.43). Population growth in terms of total seeds was similarly variable, but to a lesser extent (λ = 2.32 followed by λ = 0.32). Experimental soil disturbance led to a more than 10-fold increase in mean seedling emergence, and high sensitivity to differences in emergence carried this effect through the life cycle. In contrast, barriers to seed dispersal had no effect on population dynamics, suggesting limited dispersal in this system. Across the landscape, the presence of B. tectorum was associated with areas of higher plant diversity as opposed to those with a strong dominant (e.g. the foredune, dominated by Ammophila breviligulata, or low heathlands, characterized by Hudsonia tomentosa and Arctostaphylos uva-ursi). Overall, we find that B. tectorum is capable of both substantial population growth and decline in a dune ecosystem, but is likely limited without disturbance and dispersal agents. Thus, management actions that restrict dune access (e.g. for nesting habitat) likely have the co-benefit of limiting the invasive potential of B. tectorum. PMID:26558705

  15. Textiles for protection against microorganism

    NASA Astrophysics Data System (ADS)

    Sauperl, O.

    2016-04-01

    Concerning micro-organisms such as bacteria, viruses and fungi, there is a huge progress in the development of textile materials and procedures which should effectively protect against these various pathogens. In this sense there is especially problematic hospital environment, where it is necessary to take into account properly designed textile material which, when good selected and composed, act as a good barrier against transfer of micro-organisms through material mainly in its wet state. Respect to this it is necessary to be familiar with the rules regarding selection of the input material, the choice of proper yarn construction, the choice of the proper weaving mode, the rules regarding selection of antimicrobial-active compound suitable for (eco-friendly) treatment, and the choice of the most appropriate test method by which it is possible objectively to conclude on the reduction of selected microorganism. As is well known, fabrics are three-dimensional structures with void and non-void areas. Therefore, the physical-chemical properties of the textile material/fabric, the surface characteristics together with the shape of microorganism, and the carriers' characteristics contribute to control the transfer of microorganism through textile material. Therefore, careful planning of textile materials and treatment procedure with the compound which is able to reduce micro-organism satisfactory is particularly important, especially due to the fact that in hospital environment population with impaired immune system is mainly presented.

  16. Effectiveness of ozone against periodontal pathogenic microorganisms.

    PubMed

    Huth, Karin C; Quirling, Martina; Lenzke, Stefanie; Paschos, Ekaterini; Kamereck, Klaus; Brand, Korbinian; Hickel, Reinhard; Ilie, Nicoleta

    2011-06-01

    Ozone has been proposed as an adjunct antiseptic in periodontitis therapy. The aim of this study was to investigate the antimicrobial effectiveness of gaseous/aqueous ozone, in comparison with that of the established antiseptic chlorhexidine digluconate (CHX), against periodontal microorganisms. Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, and Parvimonas micra in planktonic or biofilm cultures were exposed, for 1 min, to gaseous ozone, aqueous ozone, CHX, or phosphate-buffered saline (control). None of the agents was able to substantially reduce the A. actinomycetemcomitans count in biofilm cultures. In contrast, P. gingivalis, T. forsythia, and P. micra could be eliminated by 2% CHX or by ozone gas at 53 gm(-3) . Significantly greater antimicrobial effects were observed against planktonic cultures than against biofilm-associated bacteria. The rate of killing was influenced by the species of bacteria, and by the type and concentration of agent. There were no significant differences in the effectiveness of aqueous ozone (20 μg ml(-1) ) or gaseous ozone (≥ 4 gm(-3) ) compared with 2% CHX but they were more effective than 0.2% CHX. Therefore, high-concentrated gaseous and aqueous ozone merit further investigation as antiseptics in periodontitis therapy. A safe system for applying gaseous ozone into the periodontal pocket that avoids inhalation still needs to be developed. PMID:21564314

  17. Temperaturegradient plates for growth of microorganisms.

    PubMed

    LANDMAN, O E; BAUSUM, H T; MATNEY, T S

    1962-03-01

    Landman, Otto E. (Fort Detrick, Frederick, Md.), Howard T. Bausum, and Thomas S. Matney. Temperature-gradient plates for growth of microorganisms. J. Bacteriol. 83:463-469. 1962.-Different temperature-gradient plates have been devised for the study of microbial growth on solid media through continuous temperature ranges or in liquid media at finely graded temperatures. All plates are made of heavy-gauge aluminum; heat supplied at one end is dissipated along the length of the metal so that a gradient is produced. The shape and range of the gradient depends on the amount of heat supplied, the insulation, the ambient temperature, and other factors. Differences of 0.2 C in temperature sensitivity between bacterial strains can be detected. The plates are simple to construct and operate. The dimensions of the aluminum, the mode of temperature measurement, and the method of heating may all be modified without diminishing the basic utility of the device.A sharp growth front develops at the maximal temperature of growth of bacteria. In most strains, all bacteria below the front form colonies and all bacteria above the front are killed, except for a few temperature-resistant mutants. PMID:14461975

  18. Serotype M3 and M28 Group A Streptococci Have Distinct Capacities to Evade Neutrophil and TNF-α Responses and to Invade Soft Tissues.

    PubMed

    Stetzner, Zachary W; Li, Dengfeng; Feng, Wenchao; Liu, Mengyao; Liu, Guanghui; Wiley, James; Lei, Benfang

    2015-01-01

    The M3 Serotype of Group A Streptococcus (GAS) is one of the three most frequent serotypes associated with severe invasive GAS infections, such as necrotizing fasciitis, in the United States and other industrialized countries. The basis for this association and hypervirulence of invasive serotype M3 GAS is not fully understood. In this study, the sequenced serotype M3 strain, MGAS315, and serotype M28 strain, MGAS6180, were characterized in parallel to determine whether contemporary M3 GAS has a higher capacity to invade soft tissues than M28 GAS. In subcutaneous infection, MGAS315 invaded almost the whole skin, inhibited neutrophil recruitment and TNF-α production, and was lethal in subcutaneous infection of mice, whereas MGAS6180 did not invade skin, induced robust neutrophil infiltration and TNF-α production, and failed to kill mice. In contrast to MGAS6180, MGAS315 had covS G1370T mutation. Either replacement of the covS1370T gene with wild-type covS in MGAS315 chromosome or in trans expression of wild-type covS in MGAS315 reduced expression of CovRS-controlled virulence genes hasA, spyCEP, and sse by >10 fold. MGAS315 covSwt lost the capacity to extensively invade skin and to inhibit neutrophil recruitment and had attenuated virulence, indicating that the covS G1370T mutation critically contribute to the hypervirulence of MGAS315. Under the background of functional CovRS, MGAS315 covSwt still caused greater lesions than MGAS6180, and, consistently under the background of covS deletion, MGAS6180 ΔcovS caused smaller lesions than MGAS315 ΔcovS. Thus, contemporary invasive M3 GAS has a higher capacity to evade neutrophil and TNF-α responses and to invade soft tissue than M28 GAS and that this skin-invading capacity of M3 GAS is maximized by natural CovRS mutations. These findings enhance our understanding of the basis for the frequent association of M3 GAS with necrotizing fasciitis. PMID:26047469

  19. The Tuberculosis Necrotizing Toxin kills macrophages by hydrolyzing NAD

    PubMed Central

    Sun, Jim; Siroy, Axel; Lokareddy, Ravi K.; Speer, Alexander; Doornbos, Kathryn S.; Cingolani, Gino; Niederweis, Michael

    2015-01-01

    Mycobacterium tuberculosis (Mtb) induces necrosis of infected cells to evade immune responses. Recently, we found that Mtb utilizes the protein CpnT to kill human macrophages by secreting its C-terminal domain, named tuberculosis necrotizing toxin (TNT) that induces necrosis by an unknown mechanism. Here we show that TNT gains access to the cytosol of Mtb-infected macrophages, where it hydrolyzes the essential co-enzyme nicotinamide adenine dinucleotide (NAD+). Expression or injection of a non-catalytic TNT mutant showed no cytotoxicity in macrophages or zebrafish zygotes, respectively, demonstrating that the NAD+-glycohydrolase activity is required for TNT-induced cell death. To prevent self-poisoning, Mtb produces an immunity factor for TNT (IFT) that binds TNT and inhibits its activity. The crystal structure of the TNT-IFT complex revealed a novel NAD+-glycohydrolase fold of TNT, which constitutes the founding member of a toxin family wide-spread in pathogenic microorganisms. PMID:26237511

  20. Timelike Killing spinors in seven dimensions

    SciTech Connect

    Cariglia, Marco; Conamhna, Oisin A.P. Mac

    2004-12-15

    We employ the G-structure formalism to study supersymmetric solutions of minimal and SU(2) gauged supergravities in seven dimensions admitting Killing spinors with an associated timelike Killing vector. The most general such Killing spinor defines a SU(3) structure. We deduce necessary and sufficient conditions for the existence of a timelike Killing spinor on the bosonic fields of the theories, and find that such configurations generically preserve one out of 16 supersymmetries. Using our general supersymmetric ansatz we obtain numerous new solutions, including squashed or deformed anti-de Sitter solutions of the gauged theory, and a large class of Goedel-like solutions with closed timelike curves.

  1. A kill curve for Phanerozoic marine species

    NASA Technical Reports Server (NTRS)

    Raup, D. M.

    1991-01-01

    A kill curve for Phanerozoic species is developed from an analysis of the stratigraphic ranges of 17,621 genera, as compiled by Sepkoski. The kill curve shows that a typical species' risk of extinction varies greatly, with most time intervals being characterized by very low risk. The mean extinction rate of 0.25/m.y. is thus a mixture of long periods of negligible extinction and occasional pulses of much higher rate. Because the kill curve is merely a description of the fossil record, it does not speak directly to the causes of extinction. The kill curve may be useful, however, to li inverted question markmit choices of extinction mechanisms.

  2. Invaders eating invaders: Exploitation of novel alien prey by the alien shimofuri goby in the San Francisco Estuary, California

    USGS Publications Warehouse

    Matern, S.A.; Brown, L.R.

    2005-01-01

    The shimofuri goby (Tridentiger bifasciatus), which is native to Asian estuaries, was recently introduced to the San Francisco Estuary, California, USA. We conducted gut content analyses to examine the goby's feeding ecology in this highly invaded estuary. Shimofuri gobies were generalist predators on benthic invertebrates, consuming seasonally abundant prey, especially amphipods (Corophium spp.). In addition, shimofuri goby utilized two novel prey items not exploited by other resident fishes - hydroids (Cordylophora caspia) and barnacle (Balanus improvisus) cirri, both of which are alien. The shimofuri goby's feeding ecology appears well-suited to the fluctuating environment of the San Francisco Estuary and may partially explain observed increases in shimofuri goby abundance compared with declines in populations of some native species. ?? Springer 2005.

  3. Antimicrobial and antibiofilm activity of pleurocidin against cariogenic microorganisms.

    PubMed

    Tao, Rui; Tong, Zhongchun; Lin, Yuan; Xue, Yunpeng; Wang, Wei; Kuang, Rong; Wang, Ping; Tian, Yu; Ni, Longxing

    2011-08-01

    Dental caries is a common oral bacterial infectious disease of global concern. Prevention and treatment of caries requires control of the dental plaque formed by pathogens such as Streptococcus mutans and Streptococcus sobrinus. Pleurocidin, produced by Pleuronectes americanus, is an antimicrobial peptide that exerts broad-spectrum activity against pathogenic bacteria and fungi. Moreover, pleurocidin shows less hemolysis and is less toxic than other natural peptides. In the present study, we investigated whether pleurocidin is an effective antibiotic peptide against common cariogenic microorganisms and performed a preliminary study of the antimicrobial mechanism. We assayed minimal inhibitory concentration (MIC), minimal bactericide concentration (MBC) and bactericidal kinetics and performed a spot-on-lawn assay. The BioFlux system was used to generate bacterial biofilms under controllable flow. Fluorescence microscopy and confocal laser scanning microscopy (CLSM) were used to analyze and observe biofilms. Scanning electron microscopy was used to observe the bacterial membrane. MIC and MBC results showed that pleurocidin had different antimicrobial activities against the tested oral strains. Although components of saliva could affect antimicrobial activity, pleurocidin dissolved in saliva still showed antimicrobial effects against oral microorganisms. Furthermore, pleurocidin showed a favorable killing effect against BioFlux flow biofilms in vitro. Our findings suggest that pleurocidin has the potential to kill dental biofilms and prevent dental caries. PMID:21703317

  4. Shock Compression and Recovery of Microorganism-Loaded Broths and AN Emulsion

    NASA Astrophysics Data System (ADS)

    Hazell, P. J.; Beveridge, C.; Groves, K.; Stennett, C.

    2009-12-01

    The microorganisms Escherichia coli, Enterococcus faecalis and Zygosaccharomyces bailii and an oil-based emulsion, have been subjected to shock compression using the flyer-plate technique to initial pressures of 0.8 GPa (in the suspension). In each experiment, a stainless steel capsule was used to contain the broths and allow for recovery without contamination. Where cavitation was mostly suppressed by virtue of simultaneous shock and dynamic compression, no kill was observed. By introducing an air gap behind the suspension, limited kill was measured in the yeast. Results also suggest that stable emulsification occurs in coarse oil-based emulsions that are subjected to shock.

  5. Exotic plant species invade hot spots of native plant diversity

    USGS Publications Warehouse

    Stohlgren, T.J.; Binkley, D.; Chong, G.W.; Kalkhan, M.A.; Schell, L.D.; Bull, K.A.; Otsuki, Y.; Newman, G.; Bashkin, M.; Yowhan, S.

    1999-01-01

    Some theories and experimental studies suggest that areas of low plant species richness may be invaded more easily than areas of high plant species richness. We gathered nested-scale vegetation data on plant species richness, foliar cover, and frequency from 200 1-m2 subplots (20 1000-m2 modified-Whittaker plots) in the Colorado Rockies (USA), and 160 1-m2 subplots (16 1000-m2 plots) in the Central Grasslands in Colorado, Wyoming, South Dakota, and Minnesota (USA) to test the generality of this paradigm. At the 1-m2 scale, the paradigm was supported in four prairie types in the Central Grasslands, where exotic species richness declined with increasing plant species richness and cover. At the 1-m2 scale, five forest and meadow vegetation types in the Colorado Rockies contradicted the paradigm; exotic species richness increased with native-plant species richness and foliar cover. At the 1000-m2 plot scale (among vegetation types), 83% of the variance in exotic species richness in the Central Grasslands was explained by the total percentage of nitrogen in the soil and the cover of native plant species. In the Colorado Rockies, 69% of the variance in exotic species richness in 1000-m2 plots was explained by the number of native plant species and the total percentage of soil carbon. At landscape and biome scales, exotic species primarily invaded areas of high species richness in the four Central Grasslands sites and in the five Colorado Rockies vegetation types. For the nine vegetation types in both biomes, exotic species cover was positively correlated with mean foliar cover, mean soil percentage N, and the total number of exotic species. These patterns of invasibility depend on spatial scale, biome and vegetation type, spatial autocorrelation effects, availability of resources, and species-specific responses to grazing and other disturbances. We conclude that: (1) sites high in herbaceous foliar cover and soil fertility, and hot spots of plant diversity (and biodiversity), are invasible in many landscapes; and (2) this pattern may be more closely related to the degree resources are available in native plant communities, independent of species richness. Exotic plant invasions in rare habitats and distinctive plant communities pose a significant challenge to land managers and conservation biologists.

  6. Bull heading to kill live gas wells

    SciTech Connect

    Oudeman, P.; Avest, D. ter; Grodal, E.O.; Asheim, H.A.; Meissner, R.J.H.

    1994-12-31

    To kill a live closed-in gas well by bull heading down the tubing, the selected pump rate should be high enough to ensure efficient displacement of the gas into the formation (i.e., to avoid the kill fluid bypassing the gas). On the other hand, the pressures that develop during bull heading at high rate must not exceed wellhead pressure rating, tubing or casing burst pressures or the formation breakdown gradient, since this will lead, at best, to a very inefficient kill job. Given these constraints, the optimum kill rate, requited hydraulic horsepower, density and type of kill fluids have to be selected. For this purpose a numerical simulator has been developed, which predicts the sequence of events during bull heading. Pressures and flow rates in the well during the kill job are calculated, taking to account slip between the gas and kill fluid, hydrostatic and friction pressure drop, wellbore gas compression and leak-off to the formation. Comparison with the results of a dedicated field test demonstrates that these parameters can be estimated accurately. Example calculations will be presented to show how the simulator can be used to identify an optimum kill scenario.

  7. Momentum kill procedure can quickly control blowouts

    SciTech Connect

    Watson, W.D. ); Moore, P. )

    1993-08-30

    The momentum kill method can help in quickly regaining control of a blowing well, providing the blowing well rate and fluid properties can be estimated reasonably. The momentum of the kill fluid counteracts and overcomes the flowing momentum of formation fluids. In other words, sufficient mud density pumped at a sufficient rate is directed into the flow stream to force the escaping fluid column back into the well bore. Sufficient kill fluid hydrostatic pressure must be stacked'' in the hole so that the well remains dead after the operation. The momentum kill is not a panacea for all blowouts. An assessment must be made of the potential problems unique to this method, and certain requirements must be met if the technique is to be successful. The paper discusses some of the considerations for evaluating the use of the momentum kill method.

  8. PCB breakdown by anaerobic microorganisms

    SciTech Connect

    Not Available

    1989-03-01

    Recently, altered PCB cogener distribution patterns observed in anaerobic sediment samples from the upper Hudson River are being attributed to biologically mediated reductive dechlorination. The authors report their successful demonstration of biologically mediated reductive dechlorination of an Aroclor mixture. In their investigation, they assessed the ability of microorganisms from PCB-contaminated Hudson River sediments (60-562 ppm PCBs) to dechlorinate Aroclor 1242 under anaerobic conditions by eluting microorganisms from the PCB- contaminated sediments and transferring them to a slurry of reduced anaerobic mineral medium and PCB-free sediments in tightly stoppered bottles. They observed dechlorination to be the most rapid at the highest PCB concentration tried by them.

  9. Killing cells by targeting mitosis.

    PubMed

    Manchado, E; Guillamot, M; Malumbres, M

    2012-03-01

    Cell cycle deregulation is a common feature of human cancer. Tumor cells accumulate mutations that result in unscheduled proliferation, genomic instability and chromosomal instability. Several therapeutic strategies have been proposed for targeting the cell division cycle in cancer. Whereas inhibiting the initial phases of the cell cycle is likely to generate viable quiescent cells, targeting mitosis offers several possibilities for killing cancer cells. Microtubule poisons have proved efficacy in the clinic against a broad range of malignancies, and novel targeted strategies are now evaluating the inhibition of critical activities, such as cyclin-dependent kinase 1, Aurora or Polo kinases or spindle kinesins. Abrogation of the mitotic checkpoint or targeting the energetic or proteotoxic stress of aneuploid or chromosomally instable cells may also provide further benefits by inducing lethal levels of instability. Although cancer cells may display different responses to these treatments, recent data suggest that targeting mitotic exit by inhibiting the anaphase-promoting complex generates metaphase cells that invariably die in mitosis. As the efficacy of cell-cycle targeting approaches has been limited so far, further understanding of the molecular pathways modulating mitotic cell death will be required to move forward these new proposals to the clinic. PMID:22223105

  10. Invading slugs (Arion vulgaris) can be vectors for Listeria monocytogenes

    PubMed Central

    Gismervik, K; Aspholm, M; Rørvik, LM; Bruheim, T; Andersen, A; Skaar, I

    2015-01-01

    Aims Listeriosis is a frequent silage-associated disease in ruminants. The slugs Arion vulgaris are invaders in gardens, vegetable crops and meadows for silage production. Field and laboratory studies were conducted to clarify whether slugs could host Listeria monocytogenes and thereby constitute a threat to animal feed safety. Methods and Results Selective culture of L. monocytogenes from 79 pooled slug samples (710 slugs) resulted in 43% positive, 16% with mean L. monocytogenes values of 405 CFU g−1 slug tissues. Of 62 individual slugs cultured, 11% also tested positive from surface/mucus. Multilocus sequence typing analysis of 36 isolates from different slug pools identified 20 sequence types belonging to L. monocytogenes lineages I and II. Slugs fed ≅4·0 × 105 CFUL. monocytogenes, excreted viable L. monocytogenes in faeces for up to 22 days. Excretion of L. monocytogenes decreased with time, although there were indications of a short enrichment period during the first 24 h. Conclusions Arion vulgaris may act as a vector for L. monocytogenes. Significance and Impact of the Study Highly slug-contaminated grass silage may pose a potential threat to animal feed safety. PMID:25580873

  11. Vegetative regeneration capacities of five ornamental plant invaders after shredding.

    PubMed

    Monty, Arnaud; Eugène, Marie; Mahy, Grégory

    2015-02-01

    Vegetation management often involves shredding to dispose of cut plant material or to destroy the vegetation itself. In the case of invasive plants, this can represent an environmental risk if the shredded material exhibits vegetative regeneration capacities. We tested the effect of shredding on aboveground and below-ground vegetative material of five ornamental widespread invaders in Western Europe that are likely to be managed by cutting and shredding techniques: Buddleja davidii (butterfly bush, Scrophulariaceae), Fallopia japonica (Japanese knotweed, Polygonaceae), Spiraea × billardii Hérincq (Billard's bridewort, Rosaceae), Solidago gigantea (giant goldenrod, Asteraceae), and Rhus typhina L. (staghorn sumac, Anacardiaceae). We looked at signs of vegetative regeneration and biomass production, and analyzed the data with respect to the season of plant cutting (spring vs summer), the type of plant material (aboveground vs below-ground), and the shredding treatment (shredded vs control). All species were capable of vegetative regeneration, especially the below-ground material. We found differences among species, but the regeneration potential was generally still present after shredding despite a reduction of growth rates. Although it should not be excluded in all cases (e.g., destruction of giant goldenrod and staghorn sumac aboveground material), the use of a shredder to destroy woody alien plant material cannot be considered as a general management option without significant environmental risk. PMID:25387455

  12. Vegetative Regeneration Capacities of Five Ornamental Plant Invaders After Shredding

    NASA Astrophysics Data System (ADS)

    Monty, Arnaud; Eugène, Marie; Mahy, Grégory

    2015-02-01

    Vegetation management often involves shredding to dispose of cut plant material or to destroy the vegetation itself. In the case of invasive plants, this can represent an environmental risk if the shredded material exhibits vegetative regeneration capacities. We tested the effect of shredding on aboveground and below-ground vegetative material of five ornamental widespread invaders in Western Europe that are likely to be managed by cutting and shredding techniques: Buddleja davidii (butterfly bush, Scrophulariaceae), Fallopia japonica (Japanese knotweed, Polygonaceae), Spiraea × billardii Hérincq (Billard's bridewort, Rosaceae), Solidago gigantea (giant goldenrod, Asteraceae), and Rhus typhina L. (staghorn sumac, Anacardiaceae). We looked at signs of vegetative regeneration and biomass production, and analyzed the data with respect to the season of plant cutting (spring vs summer), the type of plant material (aboveground vs below-ground), and the shredding treatment (shredded vs control). All species were capable of vegetative regeneration, especially the below-ground material. We found differences among species, but the regeneration potential was generally still present after shredding despite a reduction of growth rates. Although it should not be excluded in all cases (e.g., destruction of giant goldenrod and staghorn sumac aboveground material), the use of a shredder to destroy woody alien plant material cannot be considered as a general management option without significant environmental risk.

  13. Lactobacillus equigenerosi Strain Le1 Invades Equine Epithelial Cells

    PubMed Central

    Botha, Marlie; Botes, Marelize; Loos, Ben; Smith, Carine

    2012-01-01

    Lactobacillus equigenerosi strain Le1, a natural inhabitant of the equine gastrointestinal tract, survived pH 3.0 and incubation in the presence of 1.5% (wt/vol) bile salts for at least 2 h. Strain Le1 showed 8% cell surface hydrophobicity, 60% auto-aggregation, and 47% coaggregation with Clostridium difficile C6. Only 1% of the cells adhered to viable buccal epithelial cells and invaded the cells within 20 min after contact. Preincubation of strain Le1 in a buffer containing pronase prevented adhesion to viable epithelial cells. Preincubation in a pepsin buffer delayed invasion from 20 min to 1 h. Strain Le1 did not adhere to nonviable epithelial cells. Administration of L. equigenerosi Le1 (1 × 109 CFU per 50 kg body weight) to healthy horses did not increase white blood cell numbers. Differential white blood cell counts and aspartate aminotransferase levels remained constant. Glucose, lactate, cholesterol, and urea levels remained constant during administration with L. equigenerosi Le1 but decreased during the week after administration. PMID:22504808

  14. Recruitment of two Opuntia species invading abandoned olive groves

    NASA Astrophysics Data System (ADS)

    Gimeno, Isabel; Vilà, Montserrat

    2002-08-01

    In Europe, many agricultural areas are now abandoned and hence can be invaded by exotic species. The abundance and spatial distribution patterns of two Opuntia species were studied in old olive groves in the Parc Natural del Cap de Creus, Catalonia (Spain). Seedling recruitment (97.3% and 51.5% of juveniles for O. maxima and O. stricta, respectively) was higher than recruitment by cladodes. O. maxima had more seedlings recruited beneath olive trees and beneath Opuntia adults than expected. Most O. stricta seedlings were also located beneath Opuntia adult plants. However, although most seedlings were recruited beneath Opuntia, some (10-30%) were found away from putative parental plants. This may be due to seed dispersal by birds and wild boars. Seeds dispersed by wild boars were not significantly more viable than seeds from intact fruits. Seedlings grow very slowly but have a high survival rate. In conclusion, Opuntia seedling recruitment is very successful and ensures the persistence of these species within old olive groves. Consequently, it prevents restoration from an agricultural land-use back to the native community.

  15. BIOCONCENTRATION OF TOXAPHENE BY MICROORGANISMS

    EPA Science Inventory

    Analyses (glc) of extracts from whole cultures (medium and microorganisms) gave the same 'fingerprint' chromatogram as the control, indicating that toxaphene was not degraded even after extended periods of time. The insecticide was also added to autoclaved cultures of bacteria, f...

  16. How microorganisms avoid phagocyte attraction.

    PubMed

    Bestebroer, Jovanka; De Haas, Carla J C; Van Strijp, Jos A G

    2010-05-01

    Microorganisms have developed several mechanisms to modulate the host immune system to increase their survival and propagation in the host. Their presence in the host is not only revealed by self-produced peptides but also through host-derived chemokines and active complement fragments. These so-called chemoattractants are recognized by G protein-coupled receptors (GPCRs) expressed on leukocyte cell membranes. Activation of GPCRs triggers leukocyte activation and guides their recruitment to the site of infection. Therefore, GPCRs play a central role in leukocyte trafficking leading to microbial clearance. It is therefore not surprising that microorganisms are able to sabotage this arm of the immune response. Different microorganisms have evolved a variety of tactics to modulate GPCR activation. Here, we review the mechanisms and proteins used by major human pathogens and less virulent microorganisms that affect GPCR signaling. While viruses generally produce receptor and chemoattractant mimics, parasites and bacteria such as Staphylococcus aureus, Streptococcus pyogenes, Porphyromonas gingivalis, and Bordetella pertussis secrete proteins that affect receptor signaling, directly antagonize receptors, cleave stimuli, and even prevent stimulus generation. As the large arsenal of GPCR modulators aids prolonged microbial persistence in the host, their study provides us a better understanding of microbial pathogenesis. PMID:20059549

  17. Smaller Fleas: Viruses of Microorganisms

    PubMed Central

    Hyman, Paul; Abedon, Stephen T.

    2012-01-01

    Life forms can be roughly differentiated into those that are microscopic versus those that are not as well as those that are multicellular and those that, instead, are unicellular. Cellular organisms seem generally able to host viruses, and this propensity carries over to those that are both microscopic and less than truly multicellular. These viruses of microorganisms, or VoMs, in fact exist as the world's most abundant somewhat autonomous genetic entities and include the viruses of domain Bacteria (bacteriophages), the viruses of domain Archaea (archaeal viruses), the viruses of protists, the viruses of microscopic fungi such as yeasts (mycoviruses), and even the viruses of other viruses (satellite viruses). In this paper we provide an introduction to the concept of viruses of microorganisms, a.k.a., viruses of microbes. We provide broad discussion particularly of VoM diversity. VoM diversity currently spans, in total, at least three-dozen virus families. This is roughly ten families per category—bacterial, archaeal, fungal, and protist—with some virus families infecting more than one of these microorganism major taxa. Such estimations, however, will vary with further discovery and taxon assignment and also are dependent upon what forms of life one includes among microorganisms. PMID:24278736

  18. Spacetime encodings. III. Second order Killing tensors

    NASA Astrophysics Data System (ADS)

    Brink, Jeandrew

    2010-01-01

    This paper explores the Petrov type D, stationary axisymmetric vacuum (SAV) spacetimes that were found by Carter to have separable Hamilton-Jacobi equations, and thus admit a second-order Killing tensor. The derivation of the spacetimes presented in this paper borrows from ideas about dynamical systems, and illustrates concepts that can be generalized to higher-order Killing tensors. The relationship between the components of the Killing equations and metric functions are given explicitly. The origin of the four separable coordinate systems found by Carter is explained and classified in terms of the analytic structure associated with the Killing equations. A geometric picture of what the orbital invariants may represent is built. Requiring that a SAV spacetime admits a second-order Killing tensor is very restrictive, selecting very few candidates from the group of all possible SAV spacetimes. This restriction arises due to the fact that the consistency conditions associated with the Killing equations require that the field variables obey a second-order differential equation, as opposed to a fourth-order differential equation that imposes the weaker condition that the spacetime be SAV. This paper introduces ideas that could lead to the explicit computation of more general orbital invariants in the form of higher-order Killing tensors.

  19. Spacetime encodings. III. Second order Killing tensors

    SciTech Connect

    Brink, Jeandrew

    2010-01-15

    This paper explores the Petrov type D, stationary axisymmetric vacuum (SAV) spacetimes that were found by Carter to have separable Hamilton-Jacobi equations, and thus admit a second-order Killing tensor. The derivation of the spacetimes presented in this paper borrows from ideas about dynamical systems, and illustrates concepts that can be generalized to higher-order Killing tensors. The relationship between the components of the Killing equations and metric functions are given explicitly. The origin of the four separable coordinate systems found by Carter is explained and classified in terms of the analytic structure associated with the Killing equations. A geometric picture of what the orbital invariants may represent is built. Requiring that a SAV spacetime admits a second-order Killing tensor is very restrictive, selecting very few candidates from the group of all possible SAV spacetimes. This restriction arises due to the fact that the consistency conditions associated with the Killing equations require that the field variables obey a second-order differential equation, as opposed to a fourth-order differential equation that imposes the weaker condition that the spacetime be SAV. This paper introduces ideas that could lead to the explicit computation of more general orbital invariants in the form of higher-order Killing tensors.

  20. Babesia microti Primarily Invades Mature Erythrocytes in Mice

    PubMed Central

    Borggraefe, Ingo; Yuan, Jie; Telford, Sam R.; Menon, Sanjay; Hunter, Rouette; Shah, Sohela; Spielman, Andrew; Gelfand, Jeffrey A.; Wortis, Henry H.; Vannier, Edouard

    2006-01-01

    Babesia microti is a tick-borne red blood cell parasite that causes babesiosis in people. Its most common vertebrate reservoir is the white-footed mouse. To determine whether B. microti invades reticulocytes, as does the canine pathogen B. gibsoni, we infected the susceptible inbred mouse strains C.B-17.scid and DBA/2 with a clinical isolate of B. microti. Staining of fixed permeabilized red blood cells with 4′,6′-diamidino-2-phenylindole or YOYO-1, a sensitive nucleic acid stain, revealed parasite nuclei as large bright dots. Flow cytometric analysis indicated that parasite DNA is primarily found in mature erythrocytes that expressed Babesia antigens but not the transferrin receptor CD71. In contrast, CD71-positive reticulocytes rarely contained Babesia nuclei and failed to express Babesia antigens. Accordingly, the frequency of YOYO-1-positive, CD71-negative cells strongly correlated with parasitemia, defined as the frequency of infected red blood cells assessed on Giemsa-stained blood smears. Importantly, the absolute numbers generated by the two techniques were similar. Parasitemia was modest and transient in DBA/2 mice but intense and sustained in C.B-17.scid mice. In both strains, parasitemia preceded reticulocytosis, but reticulocytes remained refractory to B. microti. In immunocompetent C.B-17 mice, reticulocytosis developed early, despite a marginal and short-lived parasitemia. Likewise, an early reticulocytosis developed in resistant BALB/cBy and B10.D2 mice. These studies establish that B. microti has a tropism for mature erythrocytes. Although reticulocytes are rarely infected, the delayed reticulocytosis in susceptible strains may result from parasite or host activities to limit renewal of the mature erythrocyte pool, thereby preventing an overwhelming parasitemia. PMID:16714547

  1. Porphyromonas gingivalis invades human pocket epithelium in vitro.

    PubMed

    Sandros, J; Papapanou, P N; Nannmark, U; Dahlén, G

    1994-01-01

    The present study examined the adhesive and invasive potential of Porphyromonas gingivalis interacting with human pocket epithelium in vitro. Pocket epithelial tissue, obtained during periodontal surgery of patients with advanced periodontal disease, generated a stratified epithelium in culture. P. gingivalis strains W50 and FDC 381 (laboratory strains), OMGS 712, 1439, 1738, 1739 and 1743 (clinical isolates) as well as Escherichia coli strain HB101 (non-adhering control) were tested with respect to epithelial adhesion and invasion. Adhesion was quantitated by scintillation spectrometry after incubation of radiolabeled bacteria with epithelial cells. The invasive ability of P. gingivalis was measured by means of an antibiotic protection assay. The epithelial multilayers were infected with the test and control strains and subsequently incubated with an antibiotic mixture (metronidazole 0.1 mg/ml and gentamicin 0.5 mg/ml). The number of internalized bacteria surviving the antibiotic treatment was assessed after plating lyzed epithelial cells on culture media. All tested P. gingivalis strains adhered to and entered pocket epithelial cells. However, considerable variation in their adhesive and invasive potential was observed. E. coli strain HB101 did not adhere or invade. Transmission electron microscopy revealed that internalization of P. gingivalis was preceded by formation of microvilli and coated pits on the epithelial cell surfaces. Intracellular bacteria were most frequently surrounded by endosomal membranes; however, bacteria devoid of such membranes were also seen. Release of outer membrane vesicles (blebs) by internalized P. gingivalis was observed. These results support and extend previous work from this laboratory which demonstrated invasion of a human oral epithelial cell-line (KB) by P. gingivalis. PMID:8113953

  2. [Killing of cattle via electrical stunning].

    PubMed

    Maurer, B; Forster, S

    2007-04-01

    For disease control in the case of epidemics killing of cattle via electrical stunning is a method of choice. The official veterinarian is responsible for monitoring the adhesion to animal welfare principles during electrical stunning and killing. This requires specialised knowledge and experience as the symptoms of effective stunning are quite variable in cattle. Signs of effective and ineffective stunning are described below. In addition to suitable technical equipment, restraint of the animals and correct use of the equipment, neurophysiological processes have to be considered. Calm handling of the animals avoiding stress is a prerequisite for ensuring animal welfare and minimising pain especially when killing cattle using electrical methods. PMID:17484500

  3. Maternal decidual macrophages inhibit NK cell killing of invasive cytotrophoblasts during human pregnancy.

    PubMed

    Co, Elizabeth C; Gormley, Matthew; Kapidzic, Mirhan; Rosen, David B; Scott, Marvin A; Stolp, Haley A R; McMaster, Michael; Lanier, Lewis L; Bárcena, Alicia; Fisher, Susan J

    2013-06-01

    Human pregnancy is an immunological paradox. Semiallogeneic (fetal) placental cells (extravillous cytotrophoblasts [CTBs]) invade the uterine lining (decidua), which contains a unique decidual natural killer (dNK) cell population, identified by the cell surface phenotype CD56(bright) CD16(-) CD3(-) and CD14(+) CD206(+) macrophages (dMac). Previous reports suggested that human dNK cells are not a threat to the fetoplacental unit because they are anergic. In contrast, here we showed that purified and exogenously stimulated dNK cells are capable killers of cellular targets, including semiallogeneic CTBs. However, dMacs in the decidual leukocyte (DL) population restrained dNK killing through a transforming growth factor beta1 (TGF-beta1)-dependent mechanism. Our findings support a new model whereby dNK cells, capable of killing CTBs, are prevented from doing so by neighboring macrophages, thus protecting the fetal cells from NK cell attack. We speculate that this mechanism would inhibit dNK cell-mediated killing, even under conditions where high levels of cytokines may stimulate dNK cells, which could pose a threat to the developing placenta. PMID:23553431

  4. Characterizing invading glioma cells based on IDH1-R132H and Ki-67 immunofluorescence.

    PubMed

    Sabit, Hemragul; Nakada, Mitsutoshi; Furuta, Takuya; Watanabe, Takuya; Hayashi, Yutaka; Sato, Hiroshi; Kato, Yukinari; Hamada, Jun-ichiro

    2014-10-01

    Glioma, the most common primary brain tumor, is characterized by proliferative-invasive growth. However, the detailed biological characteristics of invading glioma cells remain to be elucidated. A monoclonal antibody (clone HMab-1) that specifically and sensitively recognizes the isocitrate dehydrogenase-1 (IDH1) protein carrying the R132H mutation can identify invading glioma cells by immunostaining. To investigate the degree of invasion in gliomas of distinct grades and the proliferative capacity of the invading cells, immunofluorescent staining was conducted using antibodies against IDH1-R132H and Ki-67 on 11 surgical and autopsy specimens of the tumor core and the invading area. Higher numbers of IDH1-R132H-positive cells in the invading area correlated with a higher tumor grade. Double staining for IDH1-R132H and Ki-67 demonstrated that most invading cells that expressed IDH1-R132H were not stained by the Ki-67 antibody, and the ratio of Ki-67-positive cells among IDH1-R132H-positive cells was significantly lower in the invasion area than in the tumor core in all grades of glioma. These data suggest that higher grade gliomas have a greater invasive potential and that invading cells possess low proliferative capacity. PMID:24384677

  5. The geometry of D = 11 Killing spinors

    NASA Astrophysics Data System (ADS)

    Gauntlett, Jerome P.; Pakis, Stathis

    2003-04-01

    We propose a way to classify all supersymmetric configurations of D=11 supergravity using the G-structures defined by the Killing spinors. We show that the most general bosonic geometries admitting a Killing spinor have at least a local SU(5) or an (Spin(7)l × R8) × R structure, depending on whether the Killing vector constructed from the Killing spinor is timelike or null, respectively. In the former case we determine what kind of local SU(5) structure is present and show that almost all of the form of the geometry is determined by the structure. We also deduce what further conditions must be imposed in order that the equations of motion are satisfied. We illustrate the formalism with some known solutions and also present some new solutions including a rotating generalisation of the resolved membrane solutions and generalisations of the recently constructed D=11 Godel solution.

  6. Quantum integrability of quadratic Killing tensors

    SciTech Connect

    Duval, C.; Valent, G.

    2005-05-01

    Quantum integrability of classical integrable systems given by quadratic Killing tensors on curved configuration spaces is investigated. It is proven that, using a 'minimal' quantization scheme, quantum integrability is ensured for a large class of classic examples.

  7. Killing vector fields and harmonic superfield theories

    SciTech Connect

    Groeger, Josua

    2014-09-15

    The harmonic action functional allows a natural generalisation to semi-Riemannian supergeometry, also referred to as harmonic, which resembles the supersymmetric sigma models studied in high energy physics. We show that Killing vector fields are infinitesimal supersymmetries of this harmonic action and prove three different Noether theorems in this context. En passant, we provide a homogeneous treatment of five characterisations of Killing vector fields on semi-Riemannian supermanifolds, thus filling a gap in the literature.

  8. Phosphate Biomineralization of Cambrian Microorganisms

    NASA Technical Reports Server (NTRS)

    McKay, David S.; Rozanov, Alexei Yu.; Hoover, Richard B.; Westall, Frances

    1998-01-01

    As part of a long term study of biological markers (biomarkers), we are documenting a variety of features which reflect the previous presence of living organisms. As we study meteorites and samples returned from Mars, our main clue to recognizing possible microbial material may be the presence of biomarkers rather than the organisms themselves. One class of biomarkers consists of biominerals which have either been precipitated directly by microorganisms, or whose precipitation has been influenced by the organisms. Such microbe-mediated mineral formation may include important clues to the size, shape, and environment of the microorganisms. The process of fossilization or mineralization can cause major changes in morphologies and textures of the original organisms. The study of fossilized terrestrial organisms can help provide insight into the interpretation of mineral biomarkers. This paper describes the results of investigations of microfossils in Cambrian phosphate-rich rocks (phosphorites) that were found in Khubsugul, Northern Mongolia.

  9. Phylogenetic relationships among subsurface microorganisms

    SciTech Connect

    Nierzwicki-Bauer, S.A.

    1991-01-01

    This report summarizes the progress made from 6/90--3/91 toward completion of our project, Phylogenetic Relationships among subsurface microorganisms. 16S rRNA was sequenced, and based on the sequence the SMCC isolates were assigned to preliminary groups. Microorganisms were obtained at various depths at the Savannah River Site, including the Surface (0 m), Congaree (91 m), and Middendorf (244 m, 259 m, 265 m). Sequence data from four isolates from the Congaree formation indicate these microorganisms can be divided into Pseudomonas spp. or Acinetobacter spp. Three 16S rRNA probes were synthesized based on sequence data. The synthesized probes were tested through in situ hybridization. Optimal conditions for in situ hybridization were determined. Because stability of RNA-DNA hybrids is dependent on hybridization stringency, related organisms can be differentiated using a single probe under different strigencies. The results of these hybridizations agree with results obtained by Balkwill and Reeves using restriction fragment length polymorphism analysis. The RNA content of a cell reflects its metabolic state. Cells which are starved for four days are not detectable with the homologous 16S rRNA probe. However, within 15 minutes of refeeding, detectable rRNA appeared. This suggests that organisms which are undetectable in environmental samples due to starvation may be detectable after addition of nutrients. Stepwise addition of specific nutrients could indicate which nutrients are rate limiting for growth. Preliminary experiments with soil samples from the Hanford Site indicate indigenous microorganisms can be detected by oligionucleotide probes. Further, using multiple probes based on universal sequences increases the number of organisms detected. Double label experiments, using a rhodamine-labelled oligionucleotide probe with free coumarin succinimidyl ester will allow simultaneous detection of total bacteria and specific 16S rRNA containing bacteria. 4 tabs. (MHB)

  10. Optimization of microorganisms growth processes.

    PubMed

    Sbarciog, M; Loccufier, M; Noldus, E

    2011-11-01

    Microorganisms growth processes are encountered in many biotechnological applications. For an increased economic benefit, optimizing their productivity is of great interest. Often the growth is inhibited by the presence in excess of other components. Inhibition determines the occurrence of multiple equilibrium points, which makes the optimal steady state reachable only from a small region of the system state space. Thus dynamic control is needed to drive the system from an initial state (characterized by a low concentration of microorganisms) to the optimal steady state. The strategy presented in this paper relies on the solutions of two optimization problems: the problem of optimal operation for maximum productivity in steady state (steady state optimization) and the problem of the start-up to the optimal steady state (transient optimization). Steady state optimization means determining the optimal equilibrium point (the amount of microorganisms harvested is maximum). The transient optimization is solved using the maximum principle of Pontryagin. The proposed control law, which drives the bioreactor from an initial state to the optimal steady state while maximizing the productivity, consists of switching the manipulated variable (dilution rate) from the minimum to the maximum value and then to the optimal value at well defined instants. This control law substantially increases the stability region of the optimal equilibrium point. Aside its efficiency, the strategy is also characterized by simplicity, being thus appropriate for implementation in real-life systems. Another important advantage is its generality: this technique may be applied to any microorganisms growth process which involves only one biochemical reaction. This means that the sequence of the control levels does not depend on the structure and parameters of the reaction kinetics, the values of the yield coefficients or the number of components in the bioreactor. PMID:20615574

  11. Steroid metabolism with intestinal microorganisms.

    PubMed

    Groh, H; Schade, K; Hörhold-Schubert, C

    1993-01-01

    As a result of the metabolic activities of numerous anaerobic microorganisms with sterols, bile acids and steroid hormones as substrates in connection with the enterohepatic circulation of these compounds, the intestine may be considered as an "endocrine" active site or organ. The review summarizes transformations of steroids by anaerobic intestinal bacteria, the physiological and supposed pathophysiological meaning thereof. The aim is to recommend further investigation in this field with respect to both the elucidation of the reactions and biological responses. PMID:8478793

  12. Microorganism Utilization for Synthetic Milk

    NASA Technical Reports Server (NTRS)

    Morford, Megan A.; Khodadad, Christina L.; Caro, Janicce I.; Spencer, LaShelle E.; Richards, Jeffery T.; Strayer, Richard F.; Birmele, Michele N.; Wheeler, Raymond M.

    2014-01-01

    A desired architecture for long duration spaceflight, like aboard the International Space Station or for future missions to Mars, is to provide a supply of fresh food crops for the astronauts. However, some crops can create a high proportion of inedible plant waste. The main goal of the Synthetic Biology project, Cow in a Column, was to produce the components of milk (sugar, lipid, protein) from inedible plant waste by utilizing microorganisms (fungi, yeast, bacteria). Of particular interest was utilizing the valuable polysaccharide, cellulose, found in plant waste, to naturally fuel-through microorganism cellular metabolism- the creation of sugar (glucose), lipid (milk fat), and protein (casein) in order to produce a synthetic edible food product. Environmental conditions such as pH, temperature, carbon source, aeration, and choice microorganisms were optimized in the laboratory and the desired end-products, sugars and lipids, were analyzed. Trichoderma reesei, a known cellulolytic fungus, was utilized to drive the production of glucose, with the intent that the produced glucose would serve as the carbon source for milk fat production and be a substitute for the milk sugar lactose. Lipid production would be carried out by Rhodosporidium toruloides, yeast known to accumulate those lipids that are typically found in milk fat. Results showed that glucose and total lipid content were below what was expected during this phase of experimentation. In addition, individual analysis of six fatty acids revealed that the percentage of each fatty acid was lower than naturally produced bovine milk. Overall, this research indicates that microorganisms could be utilized to breakdown inedible solid waste to produce useable products. For future work, the production of the casein protein for milk would require the development of a genetically modified organism, which was beyond the scope of the original project. Additional trials would be needed to further refine the required environment/organisms for the production of desired sugar and lipid end-products.

  13. Secondary imbibition in NAPL-invaded mixed-wet sediments.

    PubMed

    Al-Futaisi, Ahmed; Patzek, Tad W

    2004-10-01

    A previously developed pore network model is used here to study the spontaneous and forced secondary imbibition of a NAPL-invaded sediment, as in the displacement of NAPL by waterflooding a mixed-wet soil. We use a 3D disordered pore network with a realistic representation of pore geometry and connectivity, and a quasi-static displacement model that fully describes the pore-scale physics. After primary drainage (NAPL displacing water) up to a maximum capillary pressure, we simulate secondary imbibition (water displacing NAPL). We conduct a parametric study of imbibition by varying systematically the controlling parameters: the advancing contact angles, the fraction of NAPL-wet pores, the interfacial tension, and the initial water saturation. Once the secondary imbibition is completed, the controlling displacement mechanisms, capillary pressures, relative permeabilities, and trapped NAPL saturations are reported. It is assumed that NAPL migrates into an initially strongly water-wet sediment, i.e., the receding contact angles are very small. However, depending on the surface mineralogy and chemical compositions of the immiscible fluid phases, the wettability of pore interiors is altered while the neighborhoods of pore corners remain strongly water-wet-resulting in a mixed-wet sediment. Here, we compare three different levels of wettability alteration: water-wet (advancing contact angles (20 degrees to 55 degrees), intermediate-wet (55 degrees to 120 degrees), and NAPL-wet (120 degrees to 155 degrees). The range of advancing contact angles and the fraction of NAPL-wet pores have dramatic effects on the NAPL-water capillary pressures and relative permeabilities. The spatially inhomogeneous interfacial tension has a minor impact on the trapped NAPL saturation and relative permeability to NAPL, and a slight effect on the relative permeability to water. The initial water saturation has a slight effect on the two-phase flow characteristics of water-wet sediments; however, with more NAPL-wet pores in the sediment, it starts to have a profound effect on the water and NAPL relative permeabilities. PMID:15358487

  14. Microsphere fluoroimmunoassay for microorganisms: An update

    SciTech Connect

    Whitten, W.B.; Ramsey, J.M.; Bronk, B.V.

    1994-12-31

    Microspheres are used as labels in a fluorescence immunoassay for individual microorganisms. The diameter of a sphere that has reacted with microorganisms is determined from measurements of the optical resonance frequencies. The spheres have been coated with antibodies so that each microsphere diameter corresponds to a different species of microorganism. Further experiments on specificity and on optical resonance measurements are presented.

  15. 40 CFR 725.420 - Recipient microorganisms.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Recipient microorganisms. 725.420 Section 725.420 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS General Exemptions for New Microorganisms § 725.420 Recipient...

  16. 40 CFR 725.420 - Recipient microorganisms.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Recipient microorganisms. 725.420 Section 725.420 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS General Exemptions for New Microorganisms § 725.420 Recipient...

  17. 40 CFR 725.85 - Microorganism identity.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Microorganism identity. 725.85 Section... ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information 725.85 Microorganism identity. (a) Claims applicable to the period prior...

  18. 40 CFR 725.420 - Recipient microorganisms.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Recipient microorganisms. 725.420 Section 725.420 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS General Exemptions for New Microorganisms § 725.420 Recipient...

  19. Predatory Microorganisms Would Help Reclaim Water

    NASA Technical Reports Server (NTRS)

    Benjaminson, Morris A.; Lehrer, Stanley

    1995-01-01

    Wastewater-reclamation systems of proposed type use predatory, nonpathogenic microorganisms to consume pathogenic microorganisms. Unlike some other wastewater-reclamation systems, these systems do not require use of toxic chemicals, intense heat, or ionizing radiation (conductivity rays or ultraviolet) to destroy microorganisms.

  20. ALLELOPATHIC GROWTH STIMULATION OF PLANTS AND MICROORGANISMS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Growth promotion of plants by other plants and microorganisms, as well as of microorganisms by plants and other microorganisms, is discussed. Agrostemma githago in mixed culture with wheat, enhances growth and yield of wheat. Allantoin, a purine derivative and the principal component of agrostem...

  1. 40 CFR 725.85 - Microorganism identity.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Microorganism identity. 725.85 Section 725.85 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information § 725.85 Microorganism...

  2. 40 CFR 725.85 - Microorganism identity.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Microorganism identity. 725.85 Section... ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information § 725.85 Microorganism identity. (a) Claims applicable to the period prior...

  3. 40 CFR 725.85 - Microorganism identity.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Microorganism identity. 725.85 Section... ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information § 725.85 Microorganism identity. (a) Claims applicable to the period prior...

  4. Are early summer wildfires an opportunity to revegetate medusahead-invaded rangelands?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Successful revegetation of medusdahead-invaded plant communities can be prohibitively expensive, because it often requires iterative applications of integrated control and revegetation treatments. Prescribed burning has been used to control medusahead and prepare seedbeds for revegetation, but burni...

  5. Success of seeding native compared with introduced perennial vegetation for revegetating medusahead-invaded sagebrush rangeland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Millions of hectares of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle &Young) rangeland have been invaded by medusahead (Taeniatherum caput-medusae [L.] Nevski), an exotic annual grass that degrades wildlife habitat, reduces forage production, and decreases biodiversity....

  6. Decline in exotic tree density facilitates increased plant diversity: the experience from Melaleuca quinquenervia invaded wetlands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Australian tree Melaleuca quinquenervia (melaleuca) formed dense monocultural forests several decades after invading Florida and the Caribbean islands. These dominant forests have displaced native vegetation in sensitive wetland systems. We hypothesized that native plant diversity would increa...

  7. More than one way to invade: lessons from genetic studies of Carcinus shore crabs

    EPA Science Inventory

    The European green crab Carcinus maenas is one of the world's most widely recognized marine invaders. The success of this species has provided opportunities to explore genetic patterns associated with establishment and population expansion following independent introduction event...

  8. Predicting the spread of aquatic invaders: insight from 200 years of invasion by zebra mussels.

    PubMed

    Karatayev, Alexander Y; Burlakova, Lyubov E; Mastitsky, Sergey E; Padilla, Dianna K

    2015-03-01

    Understanding factors controlling the introduction and spread of species is crucial to improving the management of both natural populations and introduced species. The zebra mussel, Dreissena polymorpha, is considered the most aggressive freshwater invader in the Northern Hemisphere, and is a convenient model system for invasion biology, offering one of the best aquatic examples for examining the invasion process. We used data on 553 of the 1040 glacial lakes in the Republic of Belarus that were examined for the presence of zebra mussels. We used these data to build, test, and construct modified models to predict the spread of this invader, including selection of important parameters that could limit the spread of this invader. In spite of 200 years of continuous invasion, by 1996, zebra mussels were found in only 16.8% of all lakes studied. Of those lakes without zebra mussels in 1996, 66% were predicted to be susceptible to invasion by zebra mussels in the future, and 33% were predicted to be immune to successful invasion due to their water chemistry. Eighty lakes free of zebra mussels in 1996 were reexamined from 1997 to 2008. Of these, zebra mussels successfully invaded an additional 31 lakes, all of which were classified initially as suitable for zebra mussels; none of the lakes previously classified as unsuitable were invaded. We used the Random Forests classification algorithm with 16 environmental variables to determine the most important factors that differed between invaded lakes and those lakes suitable for invasion that have not yet been invaded. Distance to the nearest infested lakes was found to be the most important variable, followed by the lake area, color, average depth, and concentration of chloride, magnesium, and bicarbonate. This study provides a useful approach for predicting the spread of an invader across a landscape with variable habitat suitability that can be applied to a variety of species and systems. PMID:26263665

  9. Cryptococcus Neoformans Modulates Extracellular Killing by Neutrophils

    PubMed Central

    Qureshi, Asfia; Grey, Angus; Rose, Kristie L.; Schey, Kevin L.; Del Poeta, Maurizio

    2011-01-01

    We recently established a key role for host sphingomyelin synthase (SMS) in regulating the killing activity of neutrophils against Cryptococcus neoformans. In this paper, we studied the effect of C. neoformans on the killing activity of neutrophils and whether SMS would still be a player against C. neoformans in immunocompromised mice lacking T and natural killer (NK) cells (Tgε26 mice). To this end, we analyzed whether C. neoformans would have any effect on neutrophil survival and killing in vitro and in vivo. We show that unlike Candida albicans, neither the presence nor the capsule size of C. neoformans cells have any effect on neutrophil viability. Interestingly, melanized C. neoformans cells totally abrogated the killing activity of neutrophils. We monitored how exposure of neutrophils to C. neoformans cells would interfere with any further killing activity of the conditioned medium and found that pre-incubation with live but not “heat-killed” fungal cells significantly inhibits further killing activity of the medium. We then studied whether activation of SMS at the site of C. neoformans infection is dependent on T and NK cells. Using matrix-assisted laser desorption–ionization tissue imaging in infected lung we found that similar to previous observations in the isogenic wild-type CBA/J mice, SM 16:0 levels are significantly elevated at the site of infection in mice lacking T and NK cells, but only at early time points. This study highlights that C. neoformans may negatively regulate the killing activity of neutrophils and that SMS activation in neutrophils appears to be partially independent of T and/or NK cells. PMID:21960987

  10. Killing of Brucella abortus by bovine serum.

    PubMed Central

    Corbeil, L B; Blau, K; Inzana, T J; Nielsen, K H; Jacobson, R H; Corbeil, R R; Winter, A J

    1988-01-01

    Studies of the serum bactericidal system in bovine brucellosis were undertaken to investigate the role of the humoral immune response in protection of cattle against the facultative intracellular parasite Brucella abortus. Fresh sera from normal control cattle, infected cattle, and cattle immunized with B. abortus cell envelopes were collected before treatment and during the course of immunization or infection. Normal fresh bovine serum or fresh agammaglobulinemic serum from colostrum-deprived calves was effective in killing smooth virulent B. abortus 2308, but rough strains RB51 (a rough mutant of strain 2308) and 45/20 were much more sensitive to serum. The difference in susceptibility to serum was shown to be correlated with differences in lipopolysaccharide chemotype, with the more resistant strain 2308 having O polysaccharide and the more susceptible strains 45/20 and RB51 lacking O side chains. By treatment of fresh serum with MgCl2 and EGTA [ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid] killing was shown to occur via the classical pathway of complement activation. When antibody to B. abortus was present, killing of strain RB51 increased but killing of smooth strain 2308 decreased. The earliest antibody response in serum from infected animals did not interfere with killing. When affinity-purified bovine immunoglobulins specific for B. abortus smooth lipopolysaccharide were added to fresh normal bovine serum, immunoglobulin G1 (IgG1) and IgG2 isotypes blocked killing but IgM and IgA isotypes did not. Thus, it appears that serum from previously unexposed animals or animals early during infection can kill smooth B. abortus, an appropriate defense mechanism before the organism becomes intracellular. At later stages of infection, blocking antibodies predominate. Images PMID:3141287

  11. T cells kill bacteria captured by transinfection from dendritic cells and confer protection in mice.

    PubMed

    Cruz-Adalia, Aránzazu; Ramirez-Santiago, Guillermo; Calabia-Linares, Carmen; Torres-Torresano, Mónica; Feo, Lidia; Galán-Díez, Marta; Fernández-Ruiz, Elena; Pereiro, Eva; Guttmann, Peter; Chiappi, Michele; Schneider, Gerd; Carrascosa, José López; Chichón, Francisco Javier; Martínez Del Hoyo, Gloria; Sánchez-Madrid, Francisco; Veiga, Esteban

    2014-05-14

    Dendritic cells (DCs) phagocytose, process, and present bacterial antigens to T lymphocytes to trigger adaptive immunity. In vivo, bacteria can also be found inside T lymphocytes. However, T cells are refractory to direct bacterial infection, leaving the mechanisms by which bacteria invade T cells unclear. We show that T cells take up bacteria from infected DCs by the process of transinfection, which requires direct contact between the two cells and is enhanced by antigen recognition. Prior to transfer, bacteria localize to the immunological synapse, an intimate DC/T cell contact structure that activates T cells. Strikingly, T cells efficiently eliminate the transinfecting bacteria within the first hours after infection. Transinfected T cells produced high levels of proinflammatory cytokines and were able to protect mice from bacterial challenge following adoptive transfer. Thus, T lymphocytes can capture and kill bacteria in a manner reminiscent of innate immunity. PMID:24832455

  12. Kill fluid for oil field operations

    SciTech Connect

    Sydansk, R.D.

    1990-08-14

    This patent describes a process employing a kill fluid to substantially reduce the volumetric flow of formation fluid into a wellbore penetrating a formation containing the formation fluid below an earthen surface. It comprises: admixing components of a continuous flowing gel at the surface comprising of water-soluble carboxylate-containing polymer, a complex capable of crosslinking the polymer and formed of at least one electropositive chromium III species and at least one electronegative carboxylatespecies, and an aqueous solvent for the polymer and the complex; crosslinking the polymer and the complex to form the gel, wherein the kill fluid comprises the gel; placing a volume of the kill fluid in the wellbore sufficient to create a hydrostatic head which exerts a kill fluid pressure against the formation fluid substantially equal to or greater than the formation fluid pressure and thereby substantially reduces the volumetric flow of the formation fluid into the wellbore; performing an oil field operation after placing the volume of the kill fluid in the wellbore; and removing the gel from the wellbore to substantially restore the volumetric flow of the formation fluid into the wellbore.

  13. 75 FR 30299 - Drawbridge Operation Regulations; Newtown Creek, Dutch Kills, English Kills, and Their...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-01

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulations; Newtown Creek, Dutch Kills, English Kills, and Their Tributaries, NY, Maintenance AGENCY: Coast Guard, DHS. ACTION: Notice of...

  14. 75 FR 62469 - Drawbridge Operation Regulations; Newtown Creek, Dutch Kills, English Kills, and Their...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulations; Newtown Creek, Dutch Kills, English Kills, and Their Tributaries, NY, Maintenance AGENCY: Coast Guard, DHS. ACTION: Notice of...

  15. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...

  16. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...

  17. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...

  18. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...

  19. Strain ŽP - the first bacterial conjugation-based "kill"-"anti-kill" antimicrobial system.

    PubMed

    Starčič Erjavec, Marjanca; Petkovšek, Živa; Kuznetsova, Marina V; Maslennikova, Irina L; Žgur-Bertok, Darja

    2015-11-01

    As multidrug resistant bacteria pose one of the greatest risks to human health new alternative antibacterial agents are urgently needed. One possible mechanism that can be used as an alternative to traditional antibiotic therapy is transfer of killing agents via conjugation. Our work was aimed at providing a proof of principle that conjugation-based antimicrobial systems are possible. We constructed a bacterial conjugation-based "kill"-"anti-kill" antimicrobial system employing the well known Escherichia coli probiotic strain Nissle 1917 genetically modified to harbor a conjugative plasmid carrying the "kill" gene (colicin ColE7 activity gene) and a chromosomally encoded "anti-kill" gene (ColE7 immunity gene). The constructed strain acts as a donor in conjugal transfer and its efficiency was tested in several types of conjugal assays. Our results clearly demonstrate that conjugation-based antimicrobial systems can be highly efficient. PMID:26436830

  20. 'Total disability' and the wrongness of killing.

    PubMed

    Omelianchuk, Adam

    2015-08-01

    Walter Sinnott-Armstrong and Franklin G Miller recently argued that the wrongness of killing is best explained by the harm that comes to the victim, and that 'total disability' best explains the nature of this harm. Hence, killing patients who are already totally disabled is not wrong. I maintain that their notion of total disability is ambiguous and that they beg the question with respect to whether there are abilities left over that remain relevant for the goods of personhood and human worth. If these goods remain, then something more is lost in death than in 'total disability,' and their explanation of what makes killing wrong comes up short. But if total disability is equivalent with death, then their argument is an interesting one. PMID:25323315

  1. Cellulolytic Microorganisms from Thermal Environments

    SciTech Connect

    Vishnivetskaya, Tatiana A; Raman, Babu; Phelps, Tommy Joe; Podar, Mircea; Elkins, James G

    2012-01-01

    Thermal, anaerobic environments rich in decaying plant material are a potential source of novel cellulolytic bacteria. Samples collected from geothermal aquifers in the Yellowstone National Park (YNP) were used to select for cellulolytic thermophiles. Laboratory enrichments on dilute-acid pretreated plant biomass (switchgrass, Populus), and crystalline cellulose (Avicel) resulted in the isolation of 247 environmental clones. The majority of individual clones were affiliated with the cellulolytic bacteria of phylum Firmicutes, followed by xylanolytic and saccharolytic members of the phylum Dictyoglomi. Among the Firmicutes, the clones were affiliated with the genera Caldicellulosiruptor (54.4%), Caloramator (11.5%), Thermoanaerobacter (8.8%), Thermovenabulum (4.1%), and Clostridium (2.0%). From established anaerobic thermophilic enrichments a total of 81 single strains of the genera Caldicellulosiruptor (57%) and Thermoanaerobacter (43%) were isolated. With continuous flow enrichment on Avicel, increases in the relative abundance of Caloramator sp. was observed over clones detected from the Caldicellulosiruptor. Complex communities of interacting microorganisms bring about cellulose decomposition in nature, therefore using up-to-date approaches may yield novel cellulolytic microorganisms with high activity and a rapid rate of biomass conversion to biofuels.

  2. Ambiguities in 'killing' and 'letting die'.

    PubMed

    Atkinson, G M

    1983-05-01

    In a recent article Carla Kary (1980) attempts to show that there can be a significant moral difference between instances of killing and letting die. I shall maintain in Section I that Kary's argument is somewhat weakened by her failure to note an important ambiguity in the notion of killing a person. I shall also argue in Section II that a similar ambiguity affects the notion of letting someone die, and that failure to note this latter ambiguity also weakens the position developed by Robert Coburn (1980) with regard to defective newborns. PMID:6886572

  3. Cytotoxic Killing and Immune Evasion by Repair

    NASA Astrophysics Data System (ADS)

    Chan, Cliburn; George, Andrew J. T.; Stark, Jaroslav

    2007-07-01

    The interaction between the immune system and pathogens is a complex one, with pathogens constantly developing new ways of evading destruction by the immune system. The immune system's task is made even harder when the pathogen in question is an intra-cellular one (such as a virus or certain bacteria) and it is necessary to kill the infected host cell in order to eliminate the pathogen. This causes damage to the host, and such killing therefore needs to be carefully controlled, particularly in tissues with poor regenerative potential, or those involved in the immune response itself. Host cells therefore possess repair mechanisms which can counteract killing by immune cells. These in turn can be subverted by pathogens which up-regulate the resistance of infected cells to killing. In this paper, we explore the hypothesis that this repair process plays an important role in determining the efficacy of evasion and escape from immune control. We model a situation where cytotoxic T lymphocytes (CTL) and natural killer (NK) cells kill pathogen-infected and tumour cells by directed secretion of preformed granules containing perforin and granzymes. Resistance to such killing can be conferred by the expression of serine protease inhibitors (serpins). These are utilized by several virally infected and tumour cells, as well as playing a role in the protection of host bystander, immune and immuneprivileged cells. We build a simple stochastic model of cytotoxic killing, where serpins can neutralize granzymes stoichiometrically by forming an irreversible complex, and the survival of the cell is determined by the balance between serpin depletion and replenishment, which in its simplest form is equivalent to the well known shot noise process. We use existing analytical results for this process, and additional simulations to analyse the effects of repair on cytotoxic killing. We then extend the model to the case of a replicating target cell population, which gives a branching process coupled to shot noise. We show how the process of repair can have a major impact on the dynamics of pathogen evasion and escape of tumour cells from immune surveillance

  4. HIV transcription is induced with cell killing

    SciTech Connect

    Woloschak, G.E.; Schreck, S.; Chang-Liu, Chin-Mei; Panozzo, J.; Libertin, C.R.

    1993-11-01

    In this report, we demonstrate that this induction of HIV-LTR transcription occurs when stably transfected HeLa cells are exposed to agents which mediate cell killing, such as UV radiation, electroporation of sucrose buffer, prolonged heating, and low and high pH. Cells cultured following UV exposure demonstrated a peak in CAT expression that is evident in viable (but not necessarily cell division-competent) cells 24 h after exposure; this inductive response continued until at least 72 h after exposure. HIV-LTR induction was dose-dependent, and the amount of CAT transcription induced was correlated with the amount of cell killing that occurred in the culture.

  5. Community impacts of anthropogenic disturbance: natural enemies exploit multiple routes in pursuit of invading herbivore hosts

    PubMed Central

    2010-01-01

    Background Biological invasions provide a window on the process of community assembly. In particular, tracking natural enemy recruitment to invading hosts can reveal the relative roles of co-evolution (including local adaptation) and ecological sorting. We use molecular data to examine colonisation of northern Europe by the parasitoid Megastigmus stigmatizans following invasions of its herbivorous oak gallwasp hosts from the Balkans. Local host adaptation predicts that invading gallwasp populations will have been tracked primarily by sympatric Balkan populations of M. stigmatizans (Host Pursuit Hypothesis). Alternatively, ecological sorting allows parasitoid recruitment from geographically distinct populations with no recent experience of the invading hosts (Host Shift Hypothesis). Finally, we test for long-term persistence of parasitoids introduced via human trade of their hosts' galls (Introduction Hypothesis). Results Polymorphism diagnostic of different southern refugial regions was present in both mitochondrial and nuclear microsatellite markers, allowing us to identify the origins of northern European invaded range M. stigmatizans populations. As with their hosts, some invaded range populations showed genetic variation diagnostic of Balkan sources, supporting the Host Pursuit Hypothesis. In contrast, other invading populations had an Iberian origin, unlike their hosts in northern Europe, supporting the Host Shift Hypothesis. Finally, both British and Italian M. stigmatizans populations show signatures compatible with the Introduction Hypothesis from eastern Mediterranean sources. Conclusions These data reveal the continental scale of multi-trophic impacts of anthropogenic disturbance and highlight the fact that herbivores and their natural enemies may face very different constraints on range expansion. The ability of natural enemies to exploit ecologically-similar hosts with which they have had no historical association supports a major role for ecological sorting processes in the recent assembly of these communities. The multitude of origins of invading natural enemy populations in this study emphasises the diversity of mechanisms requiring consideration when predicting consequences of other biological invasions or biological control introductions. PMID:20969799

  6. Rapid kill-novel endodontic sealer and Enterococcus faecalis.

    PubMed

    Beyth, Nurit; Kesler Shvero, Dana; Zaltsman, Nathan; Houri-Haddad, Yael; Abramovitz, Itzhak; Davidi, Michael Perez; Weiss, Ervin I

    2013-01-01

    With growing concern over bacterial resistance, the identification of new antimicrobial means is paramount. In the oral cavity microorganisms are essential to the development of periradicular diseases and are the major causative factors associated with endodontic treatment failure. As quaternary ammonium compounds have the ability to kill a wide array of bacteria through electrostatic interactions with multiple anionic targets on the bacterial surface, it is likely that they can overcome bacterial resistance. Melding these ideas, we investigated the potency of a novel endodontic sealer in limiting Enterococcus faecalis growth. We used a polyethyleneimine scaffold to synthesize nano-sized particles, optimized for incorporation into an epoxy-based endodontic sealer. The novel endodontic sealer was tested for its antimicrobial efficacy and evaluated for biocompatibility and physical eligibility. Our results show that the novel sealer foundation affixes the nanoparticles, achieving surface bactericidal properties, but at the same time impeding nanoparticle penetration into eukaryotic cells and thereby mitigating a possible toxic effect. Moreover, adequate physical properties are maintained. The nanosized quaternary amine particles interact within minutes with bacteria, triggering cell death across wide pH values. Throughout this study we demonstrate a new antibacterial perspective for endodontic sealers; a novel antibacterial, effective and safe antimicrobial means. PMID:24223159

  7. Utilization of high temperature compost in space agriculture: the model compost kills Escherichia coli

    NASA Astrophysics Data System (ADS)

    Oshima, Tairo; Moriya, Toshiyuki; Yoshii, Takahiro

    The author and his colleagues have proposed the use of high temperature composting in space inhabitation. Composting has many advantages over burning in organic waste treatments. Composting is self-heating processes and needs no extra fuel. Composting requires no sophis-ticated equipment such as an incinerator. Composting emits no hazardous gases such as NOx, SOx and dioxines which are often produced by burning. The final product can be used as fer-tilizer in space farm land; resources recycling society can be constructed in space stations and space cities. In addition to these advantages, composting and compost soil may contribute to the environmental cleanup. During composting processes, harmful compounds to agricultural plants and animals can be destroyed. Seeds of weeds can be killed by high heat. Likewise pathogenic microbes in the waste can be eliminated during fermentation inside the composts. Recently we measured the survivability of E. coli in compost. E. coli was used as the represen-tative of the Gram-negative bacteria. Since many pathogenic strains belong to Gram-negative bacteria and Gram-negative bacteria are more resistant to antibiotics than gram-positive bac-teria. When E. coli cells were mixed in the compost pile of which inside temperature reaches up to 75oC, they died within a short period as expected. However, E. coli DNA was detected even after a day in high temperature compost. RNA has a shorter life-span than DNA, but was detected after incubation in compost for several hours. In addition to sterilizing effects due to high temperature, we found our compost soil has E. coli killing activity. When mixed with the compost soil at room temperature, E. coli died gradually. Extract of the compost soil also killed E. coli at room temperature, but it took a few days to eliminate E. coli completely. During the killing process, total number of living bacteria did not change, indicating that the killing activity is limited to some specific microorganisms. These findings suggest that the compost can be used to eliminate some of deleterious microbes from the environment without damages to the beneficial microbes. We are planning to test the killing activity of the com-post soil against more dangerous microorganisms such as Salmonella species, especially those pathogenic to barn animals.

  8. Mixed-Sequence Recognition of Double-Stranded DNA Using Enzymatically Stable Phosphorothioate Invader Probes.

    PubMed

    Anderson, Brooke A; Karmakar, Saswata; Hrdlicka, Patrick J

    2015-01-01

    Development of probes that allow for sequence-unrestricted recognition of double-stranded DNA (dsDNA) continues to attract much attention due to the prospect for molecular tools that enable detection, regulation, and manipulation of genes. We have recently introduced so-called Invader probes as alternatives to more established approaches such as triplex-forming oligonucleotides, peptide nucleic acids and polyamides. These short DNA duplexes are activated for dsDNA recognition by installment of +1 interstrand zippers of intercalator-functionalized nucleotides such as 2'-N-(pyren-1-yl)methyl-2'-N-methyl-2'-aminouridine and 2'-O-(pyren-1-yl)methyluridine, which results in violation of the nearest neighbor exclusion principle and duplex destabilization. The individual probes strands have high affinity toward complementary DNA strands, which generates the driving force for recognition of mixed-sequence dsDNA regions. In the present article, we characterize Invader probes that are based on phosphorothioate backbones (PS-DNA Invaders). The change from the regular phosphodiester backbone furnishes Invader probes that are much more stable to nucleolytic degradation, while displaying acceptable dsDNA-recognition efficiency. PS-DNA Invader probes therefore present themselves as interesting probes for dsDNA-targeting applications in cellular environments and living organisms. PMID:26230684

  9. Native Birds and Alien Insects: Spatial Density Dependence in Songbird Predation of Invading Oak Gallwasps

    PubMed Central

    Schönrogge, Karsten; Begg, Tracey; Stone, Graham N.

    2013-01-01

    Revealing the interactions between alien species and native communities is central to understanding the ecological consequences of range expansion. Much has been learned through study of the communities developing around invading herbivorous insects. Much less, however, is known about the significance of such aliens for native vertebrate predators for which invaders may represent a novel food source. We quantified spatial patterns in native bird predation of invading gall-inducing Andricus wasps associated with introduced Turkey oak (Quercus cerris) at eight sites across the UK. These gallwasps are available at high density before the emergence of caterpillars that are the principle spring food of native insectivorous birds. Native birds showed positive spatial density dependence in gall attack rates at two sites in southern England, foraging most extensively on trees with highest gall densities. In a subsequent study at one of these sites, positive spatial density dependence persisted through four of five sequential week-long periods of data collection. Both patterns imply that invading galls are a significant resource for at least some native bird populations. Density dependence was strongest in southern UK bird populations that have had longest exposure to the invading gallwasps. We hypothesise that this pattern results from the time taken for native bird populations to learn how to exploit this novel resource. PMID:23342048

  10. MECHANISM BY WHICH AMMONIUM FERTILIZERS KILL LARKSPUR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Environmental concerns of using pesticides on public lands have greatly reduced the use of herbicides to control tall larkspur (Delphinium barbeyi). Alternative methods of control have used ammonium sulfate placed in the crown of individual plants to kill larkspur. The objective of this study was ...

  11. Killing Hitler: A Writer's Journey and Angst.

    ERIC Educational Resources Information Center

    Thaler, Paul

    2002-01-01

    Describes the author's experiences in preparing a talk that "evokes the specter" of Adolf Hitler and in writing an historical account of a British plot to kill Hitler. Address the question of why the British allowed him to live that final year of the war. Muses on why scholars write, and the impact of violence and terrorism. (SG)

  12. Integrating Poetry and "To Kill a Mockingbird."

    ERIC Educational Resources Information Center

    Jolley, Susan Arpajian

    2002-01-01

    Outlines a method of teaching "To Kill a Mockingbird" along with the study of poetry. Notes that this method allows students to consider the themes of courage and developing compassion. Concludes that teaching such a multigenre unit allows students to look for connections among fact and fiction, the past and present, their own lives and…

  13. Can Vet Schools Teach without Killing Animals?

    ERIC Educational Resources Information Center

    Mangan, Katherine S.

    2000-01-01

    Discusses a protest by students at the University of Illinois (Urbana) College of Veterinary Medicine over the killing of animals that led to temporary curtailing of lethal animal experiments. Examines the conflict between animal rights groups and some faculty who are openly skeptical about the effectiveness of alternatives to the hands-on

  14. Peanut Roaster Temperatures Relative to Salmonella Kill

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ARS, Market Quality and Handling Research Unit, Raleigh NC 27695 In response to the limited peanut butter contamination incident of 2006/7, studies were initiated to examine the effect of various time and temperature protocols on log kill levels for Salmonella on peanuts. The objective of the work ...

  15. Can Vet Schools Teach without Killing Animals?

    ERIC Educational Resources Information Center

    Mangan, Katherine S.

    2000-01-01

    Discusses a protest by students at the University of Illinois (Urbana) College of Veterinary Medicine over the killing of animals that led to temporary curtailing of lethal animal experiments. Examines the conflict between animal rights groups and some faculty who are openly skeptical about the effectiveness of alternatives to the hands-on…

  16. School Shootings; Standards Kill Students and Society

    ERIC Educational Resources Information Center

    Angert, Betsy L.

    2008-01-01

    School shootings have been in the news of late. People ponder what occurs in classrooms today. Why would a young person wish to take a life? Within educational institutions, the killings are a concern. In our dire attempt to teach the children and ensure student success, it seems many of our offspring are lost. Some students feel separate from…

  17. Mass killings and detection of impacts

    NASA Technical Reports Server (NTRS)

    Mclaren, Digby J.

    1988-01-01

    Highly energetic bolide impacts occur and their flux is known. For larger bodies the energy release is greater than for any other short-term global phenomenon. Such impacts produce or release a large variety of shock induced changes including major atmospheric, sedimentologic, seismic and volcanic events. These events must necessarily leave a variety of records in the stratigraphic column, including mass killings resulting in major changes in population density and reduction or extinction of many taxonomic groups, followed by characteristic patterns of faunal and flora replacement. Of these effects, mass killings, marked by large-scale loss of biomass, are the most easily detected evidence in the field but must be manifest on a near-global scale. Such mass killings that appear to be approximately synchronous and involve disappearance of biomass at a bedding plane in many sedimentologically independent sections globally suggest a common cause and probable synchroneity. Mass killings identify an horizon which may be examined for evidence of cause. Geochemical markers may be ephemeral and absence may not be significant. There appears to be no reason why ongoing phenomena such as climate and sea-level changes are primary causes of anomolous episodic events.

  18. Integrating Poetry and "To Kill a Mockingbird."

    ERIC Educational Resources Information Center

    Jolley, Susan Arpajian

    2002-01-01

    Outlines a method of teaching "To Kill a Mockingbird" along with the study of poetry. Notes that this method allows students to consider the themes of courage and developing compassion. Concludes that teaching such a multigenre unit allows students to look for connections among fact and fiction, the past and present, their own lives and

  19. Antimicrobial metabolites from marine microorganisms.

    PubMed

    Habbu, Prasanna; Warad, Vijayanand; Shastri, Rajesh; Madagundi, Smita; Kulkarni, Venkatrao H

    2016-02-01

    Marine ecological niches have recently been described as "particularly promising" sources for search of new antimicrobials to combat antibiotic-resistant strains of pathogenic microorganisms. Marine organisms are excellent sources for many industrial products, but they are partly explored. Over 30 000 compounds have been isolated from marine sources. Bacteria, fungi, and cyanobacteria obtained from various marine sources secret several industrially useful bioactive compounds, possessing antibacterial, antifungal, and antimycobacterial activities. Sustainable cultivation methods for promising marine organisms and biotechnological processes for selected compounds can be developed, along with the establishment of biosensors for monitoring the target compounds. The semisynthetic modifications of marine-based bioactive compounds produce their new derivatives, structural analogs and mimetics that could serve as novel lead compounds against resistant pathogens. The present review focuses on promising antimicrobial compounds isolated from marine microbes from 1991-2013. PMID:26968676

  20. Multiplication of certain soil micro-organisms under simulated Martian conditions.

    PubMed

    Imshenetsky, A A; Kusjurina, L A; Jakshina, V M

    1970-01-01

    According to earlier observations, severe UV irradiation kills all micro-organisms in a chamber with simulated Martian conditions. However, even a thin soil layer protects buried micro-organisms from UV irradiation. The chief limiting factor for microbial multiplication under simulated Martian conditions seems to be soil humidity. Several micro-organisms were isolated from harsh environments (e.g., from Arctic, Antarctic desert and high-mountain soil samples). A strain of an oligonitrophilic mycococcus, isolated from Dixon Island, proved to be most resistant to low humidity. It multiplied in a mixture of limonite (maximal hygroscopical humidity 3.8%) + 2% (w/w) garden soil kept in a chamber simulating Martian conditions. Total cell count increased 7.6-fold and, in some experiments, 26-fold in 14 days. The oligonitrophilic mycococcus was able to grow even at a humidity level of 2.5%, that is less than maximal hygroscopical (3.8%). Under these conditions cell count increased 10-fold in 36 days. Thus, it was shown that even in Earth soils there are xerophytic micro-organisms which are able to multiply in limonite of low humidity. These data might correct our current concepts concerning microbial water requirements. One might speculate that Martian micro-organisms belong to xerophytic species. PMID:12664919

  1. Functional Basis of Microorganism Classification

    PubMed Central

    Zhu, Chengsheng; Delmont, Tom O.; Vogel, Timothy M.; Bromberg, Yana

    2015-01-01

    Correctly identifying nearest “neighbors” of a given microorganism is important in industrial and clinical applications where close relationships imply similar treatment. Microbial classification based on similarity of physiological and genetic organism traits (polyphasic similarity) is experimentally difficult and, arguably, subjective. Evolutionary relatedness, inferred from phylogenetic markers, facilitates classification but does not guarantee functional identity between members of the same taxon or lack of similarity between different taxa. Using over thirteen hundred sequenced bacterial genomes, we built a novel function-based microorganism classification scheme, functional-repertoire similarity-based organism network (FuSiON; flattened to fusion). Our scheme is phenetic, based on a network of quantitatively defined organism relationships across the known prokaryotic space. It correlates significantly with the current taxonomy, but the observed discrepancies reveal both (1) the inconsistency of functional diversity levels among different taxa and (2) an (unsurprising) bias towards prioritizing, for classification purposes, relatively minor traits of particular interest to humans. Our dynamic network-based organism classification is independent of the arbitrary pairwise organism similarity cut-offs traditionally applied to establish taxonomic identity. Instead, it reveals natural, functionally defined organism groupings and is thus robust in handling organism diversity. Additionally, fusion can use organism meta-data to highlight the specific environmental factors that drive microbial diversification. Our approach provides a complementary view to cladistic assignments and holds important clues for further exploration of microbial lifestyles. Fusion is a more practical fit for biomedical, industrial, and ecological applications, as many of these rely on understanding the functional capabilities of the microbes in their environment and are less concerned with phylogenetic descent. PMID:26317871

  2. Functional Basis of Microorganism Classification.

    PubMed

    Zhu, Chengsheng; Delmont, Tom O; Vogel, Timothy M; Bromberg, Yana

    2015-08-01

    Correctly identifying nearest "neighbors" of a given microorganism is important in industrial and clinical applications where close relationships imply similar treatment. Microbial classification based on similarity of physiological and genetic organism traits (polyphasic similarity) is experimentally difficult and, arguably, subjective. Evolutionary relatedness, inferred from phylogenetic markers, facilitates classification but does not guarantee functional identity between members of the same taxon or lack of similarity between different taxa. Using over thirteen hundred sequenced bacterial genomes, we built a novel function-based microorganism classification scheme, functional-repertoire similarity-based organism network (FuSiON; flattened to fusion). Our scheme is phenetic, based on a network of quantitatively defined organism relationships across the known prokaryotic space. It correlates significantly with the current taxonomy, but the observed discrepancies reveal both (1) the inconsistency of functional diversity levels among different taxa and (2) an (unsurprising) bias towards prioritizing, for classification purposes, relatively minor traits of particular interest to humans. Our dynamic network-based organism classification is independent of the arbitrary pairwise organism similarity cut-offs traditionally applied to establish taxonomic identity. Instead, it reveals natural, functionally defined organism groupings and is thus robust in handling organism diversity. Additionally, fusion can use organism meta-data to highlight the specific environmental factors that drive microbial diversification. Our approach provides a complementary view to cladistic assignments and holds important clues for further exploration of microbial lifestyles. Fusion is a more practical fit for biomedical, industrial, and ecological applications, as many of these rely on understanding the functional capabilities of the microbes in their environment and are less concerned with phylogenetic descent. PMID:26317871

  3. Contagion in Mass Killings and School Shootings

    PubMed Central

    Towers, Sherry; Gomez-Lievano, Andres; Khan, Maryam; Mubayi, Anuj; Castillo-Chavez, Carlos

    2015-01-01

    Background Several past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts. Methods Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed). We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event. Conclusions We find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015). We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001). All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings. PMID:26135941

  4. Biocorrosion produced by Thiobacillus-like microorganisms.

    PubMed

    López, A I; Marín, I; Amils, R

    1994-01-01

    Biocorrosion can be produced by many different microorganisms through diverse mechanisms. The biocorrosion produced by acidophilic microorganisms of the genus Thiobacillus is based on the production of sulfuric acid and ferric ion from pyrites or related mineral structures, as a result of the chemolithotrophic metabolism of these microorganisms. The products of this aerobic respiration are also powerful oxidant elements, which can produce chemical oxidations of other metallic structures. The Tinto River, a very unusual extremophilic habitat (pH around 2, and high concentration of ferric ion), product of the growth of strict chemolithotrophic microorganisms, is discussed as a model case. PMID:7946115

  5. Engineered Protease-resistant Antibodies with Selectable Cell-killing Functions*

    PubMed Central

    Kinder, Michelle; Greenplate, Allison R.; Grugan, Katharine D.; Soring, Keri L.; Heeringa, Katharine A.; McCarthy, Stephen G.; Bannish, Gregory; Perpetua, Meredith; Lynch, Frank; Jordan, Robert E.; Strohl, William R.; Brezski, Randall J.

    2013-01-01

    Molecularly engineered antibodies with fit-for-purpose properties will differentiate next generation antibody therapeutics from traditional IgG1 scaffolds. One requirement for engineering the most appropriate properties for a particular therapeutic area is an understanding of the intricacies of the target microenvironment in which the antibody is expected to function. Our group and others have demonstrated that proteases secreted by invasive tumors and pathological microorganisms are capable of cleaving human IgG1, the most commonly adopted isotype among monoclonal antibody therapeutics. Specific cleavage in the lower hinge of IgG1 results in a loss of Fc-mediated cell-killing functions without a concomitant loss of antigen binding capability or circulating antibody half-life. Proteolytic cleavage in the hinge region by tumor-associated or microbial proteases is postulated as a means of evading host immune responses, and antibodies engineered with potent cell-killing functions that are also resistant to hinge proteolysis are of interest. Mutation of the lower hinge region of an IgG1 resulted in protease resistance but also resulted in a profound loss of Fc-mediated cell-killing functions. In the present study, we demonstrate that specific mutations of the CH2 domain in conjunction with lower hinge mutations can restore and sometimes enhance cell-killing functions while still retaining protease resistance. By identifying mutations that can restore either complement- or Fc? receptor-mediated functions on a protease-resistant scaffold, we were able to generate a novel protease-resistant platform with selective cell-killing functionality. PMID:23986451

  6. Invasion Expansion: Time since introduction best predicts global ranges of marine invaders.

    PubMed

    Byers, James E; Smith, Rachel S; Pringle, James M; Clark, Graeme F; Gribben, Paul E; Hewitt, Chad L; Inglis, Graeme J; Johnston, Emma L; Ruiz, Gregory M; Stachowicz, John J; Bishop, Melanie J

    2015-01-01

    Strategies for managing biological invasions are often based on the premise that characteristics of invading species and the invaded environment are key predictors of the invader's distribution. Yet, for either biological traits or environmental characteristics to explain distribution, adequate time must have elapsed for species to spread to all potential habitats. We compiled and analyzed a database of natural history and ecological traits of 138 coastal marine invertebrate species, the environmental conditions at sites to which they have been introduced, and their date of first introduction. We found that time since introduction explained the largest fraction (20%) of the variability in non-native range size, while traits of the species and environmental variables had significant, but minimal, influence on non-native range size. The positive relationship between time since introduction and range size indicates that non-native marine invertebrate species are not at equilibrium and are still spreading, posing a major challenge for management of coastal ecosystems. PMID:26227803

  7. Metastatic Breast Cancer Cells Collectively Invade Collagen by Following a Glucose Gradient

    NASA Astrophysics Data System (ADS)

    Sun, Bo; Austin, Robert; Liu, Liyu; Duclos, Guillaume; Lee, Jeongseog; Wu, Amy; Kam, Yooseok; Sontag, Eduardo; Stone, Howard; Sturm, James; Gatenby, Robert

    2013-03-01

    We show that MDA-MB-231 metastatic breast cancer cells collectively invade a three dimensional collagen matrix by following a glucose gradient. We observe that due to the 3D physical deformation of the matrix, as measured by the displacement of reporter beads within the matrix, there exists a long range deformation mechanical field inside the matrix which serves to couple the motions of the invading metastatic cell. The invasion front of the cells is a dynamic one, with different cells assuming the lead on a time scale of 24 hours due to certain cells having higher speeds of penetration, which are not sustained. The front cell leadership is dynamic presumably due to metabolic costs associated with the long range strain field which proceeds the invading cell front, which we have imaged using confocal imaging and marker beads imbedded in the collagen matrix. Sponsored by the NCI/NIH Physical Sciences Oncology Centers

  8. Killing spinors and related symmetries in six dimensions

    NASA Astrophysics Data System (ADS)

    Batista, Carlos

    2016-03-01

    Benefiting from the index spinorial formalism, the Killing spinor equation is integrated in six-dimensional spacetimes. The integrability conditions for the existence of a Killing spinor are worked out and the Killing spinors are classified into two algebraic types; in the first type the scalar curvature of the spacetime must be negative, while in the second type the spacetime must be an Einstein manifold. In addition, the equations that define Killing-Yano (KY) and closed conformal Killing-Yano (CCKY) tensors are expressed in the index notation and, as consequence, all nonvanishing KY and CCKY tensors that can be generated from a Killing spinor are made explicit.

  9. Macrophages sense and kill bacteria through carbon monoxide–dependent inflammasome activation

    PubMed Central

    Wegiel, Barbara; Larsen, Rasmus; Gallo, David; Chin, Beek Yoke; Harris, Clair; Mannam, Praveen; Kaczmarek, Elzbieta; Lee, Patty J.; Zuckerbraun, Brian S.; Flavell, Richard; Soares, Miguel P.; Otterbein, Leo E.

    2014-01-01

    Microbial clearance by eukaryotes relies on complex and coordinated processes that remain poorly understood. The gasotransmitter carbon monoxide (CO) is generated by the stress-responsive enzyme heme oxygenase-1 (HO-1, encoded by Hmox1), which is highly induced in macrophages in response to bacterial infection. HO-1 deficiency results in inadequate pathogen clearance, exaggerated tissue damage, and increased mortality. Here, we determined that macrophage-generated CO promotes ATP production and release by bacteria, which then activates the Nacht, LRR, and PYD domains-containing protein 3 (NALP3) inflammasome, intensifying bacterial killing. Bacterial killing defects in HO-1–deficient murine macrophages were restored by administration of CO. Moreover, increased CO levels enhanced the bacterial clearance capacity of human macrophages and WT murine macrophages. CO-dependent bacterial clearance required the NALP3 inflammasome, as CO did not increase bacterial killing in macrophages isolated from NALP3-deficient or caspase-1–deficient mice. IL-1β cleavage and secretion were impaired in HO-1–deficient macrophages, and CO-dependent processing of IL-1β required the presence of bacteria-derived ATP. We found that bacteria remained viable to generate and release ATP in response to CO. The ATP then bound to macrophage nucleotide P2 receptors, resulting in activation of the NALP3/IL-1β inflammasome to amplify bacterial phagocytosis by macrophages. Taken together, our results indicate that macrophage-derived CO permits efficient and coordinated regulation of the host innate response to invading microbes. PMID:25295542

  10. Degradation of polychlorinated biphenyls by microorganisms

    SciTech Connect

    Yagi, O.; Sudo, R.

    1980-05-01

    The biodegradation of PCB's by microorganisms and the degradation pathway of PCB's are investigated. Experimental methods and materials are described. Only several strains of bacteria, Achromobacter sp., Alcaligenes sp., Acinetobacter sp., Pseudomonas sp., and soil microorganisms were able to decompose PCB's. A possible relationships between the structure and biodegradability of related biphenyl compounds was examined. (5 diagrams, 11 graphs, 18 references, 1 table)

  11. Microorganisms detected by enzyme-catalyzed reaction

    NASA Technical Reports Server (NTRS)

    Vango, S. P.; Weetall, H. H.; Weliky, N.

    1966-01-01

    Enzymes detect the presence of microorganisms in soils. The enzyme lysozymi is used to release the enzyme catalase from the microorganisms in a soil sample. The catalase catalyzes the decomposition of added hydrogen peroxide to produce oxygen which is detected manometrically. The partial pressure of the oxygen serves as an index of the samples bacteria content.

  12. Conformal killing tensors and covariant Hamiltonian dynamics

    SciTech Connect

    Cariglia, M.; Gibbons, G. W.; Holten, J.-W. van; Horvathy, P. A.; Zhang, P.-M.

    2014-12-15

    A covariant algorithm for deriving the conserved quantities for natural Hamiltonian systems is combined with the non-relativistic framework of Eisenhart, and of Duval, in which the classical trajectories arise as geodesics in a higher dimensional space-time, realized by Brinkmann manifolds. Conserved quantities which are polynomial in the momenta can be built using time-dependent conformal Killing tensors with flux. The latter are associated with terms proportional to the Hamiltonian in the lower dimensional theory and with spectrum generating algebras for higher dimensional quantities of order 1 and 2 in the momenta. Illustrations of the general theory include the Runge-Lenz vector for planetary motion with a time-dependent gravitational constant G(t), motion in a time-dependent electromagnetic field of a certain form, quantum dots, the Hénon-Heiles and Holt systems, respectively, providing us with Killing tensors of rank that ranges from one to six.

  13. [Archaeons--still unknown microorganisms].

    PubMed

    Efenberger, Magdalena; Brzezińska-Błaszczyk, Ewa; Wódz, Karolina

    2014-01-01

    Archaea is a group of microorganisms described by Carl Woese in 1977. Although Archaea have a similar cellular organization to bacteria, their cell wall and cell membrane are quite unique. Archaeal cell wall lacks peptidoglican and cell membrane is composed of ether-lipids which are far more stable than bacteria-specific esther-lipids. Besides, Archaea have some specific external structures, like: archaella, pili, hami and cannulae but their exact functions are still unclear. Most of Archaea obtain energy via anaerobic processes of simple inorganic or organic compounds, however some of these organisms are also able to generate methane in the process known as methanogesis. They reproduce by cell division or budding-like process and some studies demonstrated the mechanisms of genetic transfer such as conjugation, transduction and natural transformation for the Archaea. They are capable of forming biofilms also in interaction with bacteria. Some archaeons, such as Haloferax mediterranei and Sulfolobus islandicus can synthesize antimicrobial agents which are called archaeocins. In recent years huge progress has been made in understanding of Archaea but many aspects of their biology remain still unknown. In this review, we present recent advances in Archaea biology focusing mainly on archaeal morphology, metabolism and reproduction. PMID:25531709

  14. Lantibiotic production by pathogenic microorganisms.

    PubMed

    Daly, Karen M; Cotter, Paul D; Hill, Colin; Ross, R Paul

    2012-09-01

    Lantibiotics are ribosomally synthesised, post-translationally modified antimicrobial peptides produced by Gram positive bacteria, many which have broad-ranging antimicrobial activities. Lantibiotics have long been the subject of investigation with a view to their application as food preservatives or chemotherapeutic agents for clinical and veterinary medicine, while the associated biosynthetic machinery has been employed for peptide engineering purposes. However, although many lantibiotics are produced by generally regarded as safe or food-grade bacteria, it is increasingly apparent that a number of Gram positive pathogens, including strains of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Streptococcus pneumoniae, Streptococcus mutans, Streptococcus uberis and Enterococcus faecalis, also produce these compounds. It is proposed that production of these antimicrobials may provide the associated microorganisms with a competitive advantage when colonizing/infecting a host, thereby enhancing the virulence of the producing strain. Here we review the production of lantibiotics by these pathogens and discuss how their production may contribute to their disease-causing potential. PMID:22708496

  15. [Genome editing of industrial microorganism].

    PubMed

    Zhu, Linjiang; Li, Qi

    2015-03-01

    Genome editing is defined as highly-effective and precise modification of cellular genome in a large scale. In recent years, such genome-editing methods have been rapidly developed in the field of industrial strain improvement. The quickly-updating methods thoroughly change the old mode of inefficient genetic modification, which is "one modification, one selection marker, and one target site". Highly-effective modification mode in genome editing have been developed including simultaneous modification of multiplex genes, highly-effective insertion, replacement, and deletion of target genes in the genome scale, cut-paste of a large DNA fragment. These new tools for microbial genome editing will certainly be applied widely, and increase the efficiency of industrial strain improvement, and promote the revolution of traditional fermentation industry and rapid development of novel industrial biotechnology like production of biofuel and biomaterial. The technological principle of these genome-editing methods and their applications were summarized in this review, which can benefit engineering and construction of industrial microorganism. PMID:26204755

  16. Pathogenic Microorganisms and Pancreatic Cancer

    PubMed Central

    Wang, Chunsaier; Li, Jingnan

    2015-01-01

    Background Pancreatic cancer is one of the most lethal cancers worldwide. No effective screening methods exist, and available treatment modalities do not effectively treat the disease. Established risk factors for pancreatic cancer, including smoking, chronic pancreatitis, obesity and type 2 diabetes mellitus, collectively account for less than half of all pancreatic cancer cases. Accumulating reports have demonstrated that there is an association between pathogenic microorganisms and pancreatic cancer. Summary A substantial amount of preclinical and clinical evidence suggests that microbiota are likely to influence pancreatic carcinogenesis. This review summarizes the literature on studies examining infections that have been linked to pancreatic cancer. Key Message Helicobacter pylori infection may be a risk factor for pancreatic cancer; chronic hepatitis virus and oral microbiota may also play a role in pancreatic carcinogenesis. Practical Implications Considering the worldwide burden of the disease, the association between microbiota and pancreatic cancer in this review may provide new ideas to prevent and treat pancreatic cancer more efficiently. Further studies in this direction are urgently needed. PMID:26673459

  17. A mass killing in New Zealand.

    PubMed

    Brinded, P M; Taylor, A J

    1995-06-01

    The circumstances surrounding a mass killing in New Zealand are described in conjunction with a review of a number of other similar multiple victim homicides. Due to the rare and extreme nature of such events, it is argued that they should be managed as human disasters by the professionals involved and that stress debriefing should be available for all potential primary, secondary and tertiary victims. PMID:7487798

  18. GOETHALS BRIDGE FROM NORTH SIDE OVER ARTHUR KILL. RAILROAD BRIDGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GOETHALS BRIDGE FROM NORTH SIDE OVER ARTHUR KILL. RAILROAD BRIDGE IN FOREGROUND - Goethals Bridge, Spanning Arthur Kill from New Jersey to Staten Island, Staten Island (subdivision), Richmond County, NY

  19. 11. GENERAL INTERIOR VIEW OF KILLING FLOOR ON LEVEL 4; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. GENERAL INTERIOR VIEW OF KILLING FLOOR ON LEVEL 4; LOOKING SOUTHWEST TOWARD SPLITTERS' PLATFORMS - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  20. Designing surfaces that kill bacteria on contact

    NASA Astrophysics Data System (ADS)

    Tiller, Joerg C.; Liao, Chun-Jen; Lewis, Kim; Klibanov, Alexander M.

    2001-05-01

    Poly(4-vinyl-N-alkylpyridinium bromide) was covalently attached to glass slides to create a surface that kills airborne bacteria on contact. The antibacterial properties were assessed by spraying aqueous suspensions of bacterial cells on the surface, followed by air drying and counting the number of cells remaining viable (i.e., capable of growing colonies). Amino glass slides were acylated with acryloyl chloride, copolymerized with 4-vinylpyridine, and N-alkylated with different alkyl bromides (from propyl to hexadecyl). The resultant surfaces, depending on the alkyl group, were able to kill up to 94 ± 4% of Staphylococcus aureus cells sprayed on them. A surface alternatively created by attaching poly(4-vinylpyridine) to a glass slide and alkylating it with hexyl bromide killed 94 ± 3% of the deposited S. aureus cells. On surfaces modified with N-hexylated poly(4-vinylpyridine), the numbers of viable cells of another Gram-positive bacterium, Staphylococcus epidermidis, as well as of the Gram-negative bacteria Pseudomonas aeruginosa and Escherichia coli, dropped more than 100-fold compared with the original amino glass. In contrast, the number of viable bacterial cells did not decline significantly after spraying on such common materials as ceramics, plastics, metals, and wood.

  1. Rickettsial relative associated with male killing in the ladybird beetle (Adalia bipunctata).

    PubMed Central

    Werren, J H; Hurst, G D; Zhang, W; Breeuwer, J A; Stouthamer, R; Majerus, M E

    1994-01-01

    A cytoplasmically inherited microorganism associated with male killing in the two-spot ladybird beetle, Adalia bipunctata, is shown to be closely related to bacteria in the genus Rickettsia. Sequencing of a PCR-amplified product of the 16S genes coding for rRNA (16S rDNA) shows the organism associated with male killing in ladybirds to share a common ancestry with the Rickettsias relative to other genera (e.g., Anaplasma, Ehrlichia, and Cowdria). The rickettsial 16S rDNA product is found in four strains of ladybird beetle showing male embryo lethality and is absent from two uninfected strains and an antibiotic-cured strain. In addition, a revertant strain that had naturally lost the male-killing trait failed to amplify the rickettsial 16S rDNA product. Use of PCR primers for a 17-kDa protein antigen which is found only in rickettsias also resulted in an amplified product from infected strains. Uninfected, cured, and revertant strains and insect species infected with related bacteria (cytoplasmic-incompatibility bacteria from Nasonia wasps) failed to amplify the product. Discovery of a close relative of rickettsias associated with sex ratio distortion in insects has implications for the evolution and population dynamics of this bacterial genus. Images PMID:8288533

  2. Clinal patterns of desiccation and starvation resistance in ancestral and invading populations of Drosophila subobscura

    PubMed Central

    Gilchrist, George W; Jeffers, Lisa M; West, Brianna; Folk, Donna G; Suess, Jeremy; Huey, Raymond B

    2008-01-01

    As invading species expand, they eventually encounter physical and biotic stressors that limit their spread. We examine latitudinal and climatic variation in physiological tolerance in one native and two invading populations of Drosophila subobscura. These flies are native to the Palearctic region, but invaded both South and North America around 1980 and spread rapidly across 15° of latitude on each continent. Invading flies rapidly evolved latitudinal clines in chromosome inversion frequencies and in wing size that parallel those of native populations in the Old World. Here we investigate whether flies on all three continents have evolved parallel clines in desiccation and starvation tolerance, such that flies in low-latitude regions (hot, dry) might have increased stress resistance. Starvation tolerance does not vary with latitude or climate on any continent. In contrast, desiccation tolerance varies clinally with latitude on all three continents, although not in parallel. In North American and Europe, desiccation tolerance is inversely related to latitude, as expected. But in South America, desiccation tolerance increases with latitude and is greatest in relatively cool and wet areas. Differences among continents in latitudinal patterns of interspecific-competition potentially influence clinal selection for physiological resistance, but no simple pattern is evident on these continents. PMID:25567732

  3. A generic risk-based surveying method for invading plant pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Invasive plant pathogens are increasing with international trade and travel with damaging environmental and economic consequences. Recent examples include tree diseases such as Sudden Oak Death in the Western US and Ash Dieback in Europe. To control an invading pathogen it is crucial that newly in...

  4. Space Invaders and Pedagogical Innovators: Regional Educational Understandings from Australian Occupational Travelers

    ERIC Educational Resources Information Center

    Danaher, Patrick Alan; Danaher, Geoff; Moriarty, Beverley

    2003-01-01

    Australian occupational Travelers such as circus and fairground people often enter territories normally occupied by permanent residents. This article examines the ways in which these Travelers act as "space invaders," disrupting the boundaries between urban and rural, and as pedagogical innovators, when they develop pioneering approaches to their…

  5. Ecosystem effects of Diorhabda elongata (leaf beetle) on Tamarix invaded riparian systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Saltcedar (Tamarix ramosissima) is a pernicious invader of riparian areas in western rangelands. The release of a biocontrol agent, Diorhabda elongata (leaf beetle), was done across several western states in an effort to control saltcedar by defoliating Tamarix with a predator from its native range....

  6. Evidence for pollen limitation of a native plant in invaded communities.

    PubMed

    Da Silva, Elizabeth M; King, Vashti M; Russell-Mercier, Jake L; Sargent, Risa D

    2013-06-01

    Animal-pollinated invasive species have frequently been demonstrated to outcompete native species for pollinator attention, which can have detrimental effects on the reproductive success and population dynamics of native species. Many animal-pollinated invasive species exhibit showy flowers and provide substantial rewards, allowing them to act as pollinator 'magnets', which, at a large scale, can attract more pollinators to an area, but, at a smaller scale, may reduce compatible pollen flow to local native species, possibly explaining why most studies detect competition. By performing pollen limitation experiments of populations in both invaded and uninvaded sites, we demonstrate that the invasive plant Lythrum salicaria appears to facilitate, rather than hinder, the reproductive success of native confamilial Decodon verticillatus, even at a small scale, in a wetland habitat in southeastern Ontario. We found no evidence for a magnet species effect on pollinator attraction to invaded sites. Germination experiments confirmed that seeds from invaded sites had similar germination rates to those from uninvaded sites, making it unlikely that a difference in inbreeding was masking competitive effects. We describe several explanations for our findings. Notably, there were no differences in seed set among populations at invaded and uninvaded sites. Our results underscore the inherent complexity of studying the ecological impacts of invasive species on natives. PMID:23129400

  7. Biocontrol alters litter chemistry and short-term decomposition in a Tamarisk-invaded ecosystem

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The release of the leaf beetle (Diorhabda elongata) has resulted in the defoliation of tens of 1000’s of hectares of Tamarix-invaded systems, however little is known about the effects of biocontrol on ecosystem nutrient dynamics. Weed invasion has been linked to disturbance-induced increases in nut...

  8. Management process invaded Ames as the Center shifted from NACA to NASA oversight. Ames constructed

    NASA Technical Reports Server (NTRS)

    1968-01-01

    Management process invaded Ames as the Center shifted from NACA to NASA oversight. Ames constructed a review room in its headquarters building where, in the graphical style that prevailed in the 1960's, Ames leadership could review progress against schedule, budget and performance measures. Shown, in October 1965 is Merrill Mead chief of Ames' program and resources office. (for H Julian Allen Retirement album)

  9. Cost/benefit analysis of managing annual invasive grasses in partially invaded sagebrush steppe ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our objective was to evaluate the cost-benefit of a single herbicide application or targeted grazing of annual grasses during restoration of partially invaded sagebrush steppe ecosystems used for livestock production. The cost/benefit model used is based on estimating the production of vegetation i...

  10. Ecology and management of Sheoak (Casuarina spp.), an invader of coastal Florida, U.S.A.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Casuarina spp. are invasive weeds in Florida that threaten biological diversity and beach integrity of coastal habitats. The trees include three species and their hybrids that aggressively invade riverine and coastal areas. Of the three species, C. equisetifolia and C. glauca are highly salt tol...

  11. Perennial grass dominance: creating a resilient plant community in an exotic annual grass invaded rangeland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Millions of hectares of western rangelands have been invaded by the exotic and invasive annual grass, cheatgrass (Bromus tectorum). Cheatgrass provides a fine-textured, early maturing fuel that has increased the chance, rate, spread and season of wildfire to public and private lands throughout the ...

  12. I smell an invasive invader: Using portable gas spectrometry at ports of entry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inspectors at ports of entry are faced with the daunting task of finding a visual sign of a pest or disease. Small insects, pests concealed inside plant material and plant diseases could escape detection and invade the country. In a collaborative effort, portable gas chromatography technology was te...

  13. Restoration of exotic annual grass-invaded rangelands: importance of seed mix composition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Restoration of exotic annual grass-invaded rangelands is needed to improve ecosystem function and services. Increasing plant species and plant functional group diversity is generally believed to increase resistance to invasion and increase desired vegetation. However, the effects of diversity and ...

  14. Host stage preference, efficacy and fecundity of parasitoids attacking Drosophila suzukii in newly invaded areas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is an invasive species, native to Eastern and Southeastern Asia, that has recently colonized parts of North America and Europe. The severe damage caused by D. suzukii in the newly invaded areas is largely due to the absence of specialized natur...

  15. Are early summer wildfires an opportunity to revegetate exotic annual grass-invaded plant communities?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Medusahead (Taeniatherum caput-medusae (L.) Nevski) is an exotic annual grass reducing biodiversity and altering ecosystem function and processes in rangelands. Revegetation of medusahead-invaded plant communities is needed to improve ecosystem function, increase livestock forage production, and im...

  16. The benefits of harvesting wetland invaders for cellulosic biofuel: an ecosystem services perspective

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The growing interest in cellulosic biofuel production has led the call for alternative cropping systems that maximize production along with the accompanying regulating, supporting, and cultural ecosystem services. We evaluate the potential for biomass harvested from invaded wetlands to achieve thes...

  17. Habitat shift in invading species: Zebra and quagga mussel population characteristics on shallow soft substrates

    USGS Publications Warehouse

    Berkman, P.A.; Garton, D.W.; Haltuch, M.A.; Kennedy, G.W.; Febo, L.R.

    2000-01-01

    Unexpected habitat innovations among invading species are illustrated by the expansion of dreissenid mussels across sedimentary environments in shallow water unlike the hard substrates where they are conventionally known. In this note, records of population characteristics of invading zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussels from 1994 through 1998 are reported from shallow (less than 20 m) sedimentary habitats in western Lake Erie. Haphazard SCUBA collections of these invading species indicated that combined densities of zebra and quagga mussels ranged from 0 to 32,500 individuals per square meter between 1994 and 1998, with D. polymorpha comprising 75-100% of the assemblages. These mixed mussel populations, which were attached by byssal threads to each other and underlying sand-grain sediments, had size-frequency distributions that were typical of colonizing populations on hard substrates. Moreover, the presence of two mussel cohorts within the 1994 samples indicated that these species began expanding onto soft substrates not later than 1992, within 4 years of their initial invasion in western Lake Erie. Such historical data provide baselines for interpreting adaptive innovations, ecological interactions and habitat shifts among the two invading dreissenid mussel species in North America.

  18. "Invented Invaders": An Engaging Activity to Teach Characteristics Control of Invasive Species

    ERIC Educational Resources Information Center

    Lampert, Evan

    2015-01-01

    Invasive species, defined as exotic species that reach pest status, are major threats to global biodiversity. Although invasive species can belong to any taxonomic group, general characteristics such as rapid growth and reproduction are shared by many invasive species. "Invented Invaders" is a collaborative activity in which students

  19. Impact of Alien Plant Invaders on Pollination Networks in Two Archipelagos

    PubMed Central

    Padrón, Benigno; Traveset, Anna; Biedenweg, Tine; Díaz, Diana; Nogales, Manuel; Olesen, Jens M.

    2009-01-01

    Mutualistic interactions between plants and animals promote integration of invasive species into native communities. In turn, the integrated invaders may alter existing patterns of mutualistic interactions. Here we simultaneously map in detail effects of invaders on parameters describing the topology of both plant-pollinator (bi-modal) and plant-plant (uni-modal) networks. We focus on the invader Opuntia spp., a cosmopolitan alien cactus. We compare two island systems: Tenerife (Canary Islands) and Menorca (Balearic Islands). Opuntia was found to modify the number of links between plants and pollinators, and was integrated into the new communities via the most generalist pollinators, but did not affect the general network pattern. The plant uni-modal networks showed disassortative linkage, i.e. species with many links tended to connect to species with few links. Thus, by linking to generalist natives, Opuntia remained peripheral to network topology, and this is probably why native network properties were not affected at least in one of the islands. We conclude that the network analytical approach is indeed a valuable tool to evaluate the effect of invaders on native communities. PMID:19609437

  20. Using the Science Fiction Film "Invaders from Mars" in a Child Psychiatry Seminar

    ERIC Educational Resources Information Center

    Zerby, Stephen A.

    2005-01-01

    Objective: The science fiction film "Invaders From Mars" is used to teach principles of child development; clinical features of separation anxiety and nightmares; and clinical interventions, including child psychotherapy, child protective issues, and crisis management. Methods: Commercial films have been used as teaching aids in child psychiatry…

  1. Passive restoration potential of riparian areas invaded by giant reed (Arundo donax) in Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Giant reed (Arundo donax L.) is a rhizomatous woody non-native grass that has invaded much of the riparian areas of the southwest. By forming thick impenetrable swaths along riverbanks and waterways, giant reed has driven riparian ecosystem decline and displaced native biodiversity. It’s document...

  2. "Invented Invaders": An Engaging Activity to Teach Characteristics Control of Invasive Species

    ERIC Educational Resources Information Center

    Lampert, Evan

    2015-01-01

    Invasive species, defined as exotic species that reach pest status, are major threats to global biodiversity. Although invasive species can belong to any taxonomic group, general characteristics such as rapid growth and reproduction are shared by many invasive species. "Invented Invaders" is a collaborative activity in which students…

  3. Minimizing invader impacts: striking the right balance between removal and restoration.

    PubMed

    Hall, Richard J; Hastings, Alan

    2007-12-01

    Invasive species can cause severe damage in their introduced range; this damage often persists even after removal of the invader. In order to efficiently allocate a limited budget between invader removal and restoration of habitat from which the invader has been removed, it is vital to quantify the impacts of the invasion within an economic context. Here we develop optimal management strategies for biological invasions, which minimize both the direct economic costs of removal and restoration, and the ecological costs of present and future damage caused by the invasion. We demonstrate how this can be formulated as a linear programming problem, enabling the fast and efficient computation of optimal solutions. Using a simple example, we outline some general principles for the optimal control of an invader that damages its environment. Notably, we show that the most effective strategies often switch the priority of removal and restoration over time, and outline the conditions under which restoration is prioritized over removal. The proportion of total funds allocated to restoration will depend on the annual budget, the persistence of damage, and the relative costs of damage, removal and restoration. PMID:17920635

  4. Using the Science Fiction Film "Invaders from Mars" in a Child Psychiatry Seminar

    ERIC Educational Resources Information Center

    Zerby, Stephen A.

    2005-01-01

    Objective: The science fiction film "Invaders From Mars" is used to teach principles of child development; clinical features of separation anxiety and nightmares; and clinical interventions, including child psychotherapy, child protective issues, and crisis management. Methods: Commercial films have been used as teaching aids in child psychiatry

  5. Comparison of entomofauna between native and medusahead-invaded habitats in northeastern California and northwestern Nevada

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Medusahead (Taeniatherum caput-medusae) is a weedy grass species that has invaded large tracts of open rangeland in the western USA. Medusahead is unpalatable to livestock, reducing forage value of land, and duff from dead, matted medusahead plants increases the frequency and intensity of wildfire,...

  6. 78 FR 43063 - Drawbridge Operation Regulations; Arthur Kill, NY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-19

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulations; Arthur Kill, NY AGENCY: Coast Guard... District, has issued a temporary deviation from the regulations governing the operation of the Arthur Kill AK Railroad Bridge across Arthur Kill, mile 11.6, between Staten Island, New York and Elizabeth,...

  7. Road-Killed Animals as Resources for Ecological Studies.

    ERIC Educational Resources Information Center

    Adams, Clark E.

    1983-01-01

    Summarizes 19 literature sources identifying road-killed vertebrates and frequency of kill by numbers. Examples of how these animals can be incorporated into curricula (integrating biology, society, people, and values) are given, followed by an illustrated example of how a road-killed raccoon's skull demonstrated a human/wildlife interaction prior…

  8. 7 CFR 29.1018 - Fire-killed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Fire-killed. 29.1018 Section 29.1018 Agriculture... Type 92) § 29.1018 Fire-killed. Any leaf of which 5 percent or more of its surface has a set green... tobacco may be described as fire-killed. (See Rule 23.)...

  9. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Virus. 113.203 Section 113.203 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.203 Feline Panleukopenia Vaccine, Killed Virus. Feline Panleukopenia Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  10. 9 CFR 113.214 - Parvovirus Vaccine, Killed Virus (Canine).

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Parvovirus Vaccine, Killed Virus (Canine). 113.214 Section 113.214 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.214 Parvovirus Vaccine, Killed Virus (Canine). Parvovirus...

  11. 9 CFR 113.214 - Parvovirus Vaccine, Killed Virus (Canine).

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Parvovirus Vaccine, Killed Virus (Canine). 113.214 Section 113.214 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.214 Parvovirus Vaccine, Killed Virus (Canine). Parvovirus...

  12. 9 CFR 113.204 - Mink Enteritis Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Mink Enteritis Vaccine, Killed Virus. 113.204 Section 113.204 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.204 Mink Enteritis Vaccine, Killed Virus. Mink Enteritis...

  13. 9 CFR 113.205 - Newcastle Disease Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Virus. 113.205 Section 113.205 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.205 Newcastle Disease Vaccine, Killed Virus. Newcastle Disease Vaccine (Killed Virus) shall be prepared from virus-bearing tissues or fluids obtained from embryonated...

  14. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Virus. 113.203 Section 113.203 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.203 Feline Panleukopenia Vaccine, Killed Virus. Feline Panleukopenia Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  15. 9 CFR 113.214 - Parvovirus Vaccine, Killed Virus (Canine).

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Parvovirus Vaccine, Killed Virus (Canine). 113.214 Section 113.214 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.214 Parvovirus Vaccine, Killed Virus (Canine). Parvovirus...

  16. 9 CFR 113.204 - Mink Enteritis Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Mink Enteritis Vaccine, Killed Virus. 113.204 Section 113.204 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.204 Mink Enteritis Vaccine, Killed Virus. Mink Enteritis...

  17. 9 CFR 113.214 - Parvovirus Vaccine, Killed Virus (Canine).

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Parvovirus Vaccine, Killed Virus (Canine). 113.214 Section 113.214 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.214 Parvovirus Vaccine, Killed Virus (Canine). Parvovirus...

  18. 9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Virus. 113.210 Section 113.210 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.210 Feline Calicivirus Vaccine, Killed Virus. Feline Calicivirus Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  19. 9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Pseudorabies Vaccine, Killed Virus. 113.213 Section 113.213 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.213 Pseudorabies Vaccine, Killed Virus. Pseudorabies Vaccine,...

  20. 9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Virus. 113.210 Section 113.210 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.210 Feline Calicivirus Vaccine, Killed Virus. Feline Calicivirus Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  1. 9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Pseudorabies Vaccine, Killed Virus. 113.213 Section 113.213 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.213 Pseudorabies Vaccine, Killed Virus. Pseudorabies Vaccine,...

  2. 9 CFR 113.204 - Mink Enteritis Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Mink Enteritis Vaccine, Killed Virus. 113.204 Section 113.204 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.204 Mink Enteritis Vaccine, Killed Virus. Mink Enteritis...

  3. 9 CFR 113.205 - Newcastle Disease Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Virus. 113.205 Section 113.205 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.205 Newcastle Disease Vaccine, Killed Virus. Newcastle Disease Vaccine (Killed Virus) shall be prepared from virus-bearing tissues or fluids obtained from embryonated...

  4. 9 CFR 113.205 - Newcastle Disease Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Virus. 113.205 Section 113.205 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.205 Newcastle Disease Vaccine, Killed Virus. Newcastle Disease Vaccine (Killed Virus) shall be prepared from virus-bearing tissues or fluids obtained from embryonated...

  5. 9 CFR 113.204 - Mink Enteritis Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Mink Enteritis Vaccine, Killed Virus. 113.204 Section 113.204 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.204 Mink Enteritis Vaccine, Killed Virus. Mink Enteritis...

  6. 9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Pseudorabies Vaccine, Killed Virus. 113.213 Section 113.213 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.213 Pseudorabies Vaccine, Killed Virus. Pseudorabies Vaccine,...

  7. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Virus. 113.203 Section 113.203 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.203 Feline Panleukopenia Vaccine, Killed Virus. Feline Panleukopenia Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  8. 9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Virus. 113.210 Section 113.210 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.210 Feline Calicivirus Vaccine, Killed Virus. Feline Calicivirus Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  9. 9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Virus. 113.210 Section 113.210 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.210 Feline Calicivirus Vaccine, Killed Virus. Feline Calicivirus Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  10. 9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Pseudorabies Vaccine, Killed Virus. 113.213 Section 113.213 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.213 Pseudorabies Vaccine, Killed Virus. Pseudorabies Vaccine,...

  11. 9 CFR 113.205 - Newcastle Disease Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Virus. 113.205 Section 113.205 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.205 Newcastle Disease Vaccine, Killed Virus. Newcastle Disease Vaccine (Killed Virus) shall be prepared from virus-bearing tissues or fluids obtained from embryonated...

  12. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Virus. 113.203 Section 113.203 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... REQUIREMENTS Killed Virus Vaccines § 113.203 Feline Panleukopenia Vaccine, Killed Virus. Feline Panleukopenia Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  13. 7 CFR 29.1018 - Fire-killed.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Fire-killed. 29.1018 Section 29.1018 Agriculture... Type 92) 29.1018 Fire-killed. Any leaf of which 5 percent or more of its surface has a set green... tobacco may be described as fire-killed. (See Rule 23.)...

  14. 7 CFR 29.1018 - Fire-killed.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Fire-killed. 29.1018 Section 29.1018 Agriculture... Type 92) 29.1018 Fire-killed. Any leaf of which 5 percent or more of its surface has a set green... tobacco may be described as fire-killed. (See Rule 23.)...

  15. 7 CFR 29.1018 - Fire-killed.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Fire-killed. 29.1018 Section 29.1018 Agriculture... Type 92) 29.1018 Fire-killed. Any leaf of which 5 percent or more of its surface has a set green... tobacco may be described as fire-killed. (See Rule 23.)...

  16. Special killing forms on toric Sasaki-Einstein spaces

    NASA Astrophysics Data System (ADS)

    Visinescu, Mihai

    2014-11-01

    We summarize recent results on the construction of the special Killing forms on toric Sasaki-Einstein manifolds. The Killing forms are associated with the contact forms of the Sasaki spaces. Besides these there are two additional Killing forms connected with the parallel forms of the Calabi-Yau cone manifolds.

  17. 7 CFR 29.1018 - Fire-killed.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Fire-killed. 29.1018 Section 29.1018 Agriculture... Type 92) § 29.1018 Fire-killed. Any leaf of which 5 percent or more of its surface has a set green... tobacco may be described as fire-killed. (See Rule 23.)...

  18. Global Invader Impact Network (GIIN): toward standardized evaluation of the ecological impacts of invasive plants.

    PubMed

    Barney, Jacob N; Tekiela, Daniel R; Barrios-Garcia, Maria Noelia; Dimarco, Romina D; Hufbauer, Ruth A; Leipzig-Scott, Peter; Nuñez, Martin A; Pauchard, Aníbal; Pyšek, Petr; Vítková, Michaela; Maxwell, Bruce D

    2015-07-01

    Terrestrial invasive plants are a global problem and are becoming ubiquitous components of most ecosystems. They are implicated in altering disturbance regimes, reducing biodiversity, and changing ecosystem function, sometimes in profound and irreversible ways. However, the ecological impacts of most invasive plants have not been studied experimentally, and most research to date focuses on few types of impacts, which can vary greatly among studies. Thus, our knowledge of existing ecological impacts ascribed to invasive plants is surprisingly limited in both breadth and depth. Our aim was to propose a standard methodology for quantifying baseline ecological impact that, in theory, is scalable to any terrestrial plant invader (e.g., annual grasses to trees) and any invaded system (e.g., grassland to forest). The Global Invader Impact Network (GIIN) is a coordinated distributed experiment composed of an observational and manipulative methodology. The protocol consists of a series of plots located in (1) an invaded area; (2) an adjacent removal treatment within the invaded area; and (3) a spatially separate uninvaded area thought to be similar to pre-invasion conditions of the invaded area. A standardized and inexpensive suite of community, soil, and ecosystem metrics are collected allowing broad comparisons among measurements, populations, and species. The method allows for one-time comparisons and for long-term monitoring enabling one to derive information about change due to invasion over time. Invader removal plots will also allow for quantification of legacy effects and their return rates, which will be monitored for several years. GIIN uses a nested hierarchical scale approach encompassing multiple sites, regions, and continents. Currently, GIIN has network members in six countries, with new members encouraged. To date, study species include representatives of annual and perennial grasses; annual and perennial forbs; shrubs; and trees. The goal of the GIIN framework is to create a standard yet flexible platform for understanding the ecological impacts of invasive plants, allowing both individual and synthetic analyses across a range of taxa and ecosystems. If broadly adopted, this standard approach will offer unique insight into the ecological impacts of invasive plants at local, regional, and global scales. PMID:26306173

  19. Global Invader Impact Network (GIIN): toward standardized evaluation of the ecological impacts of invasive plants

    PubMed Central

    Barney, Jacob N; Tekiela, Daniel R; Barrios-Garcia, Maria Noelia; Dimarco, Romina D; Hufbauer, Ruth A; Leipzig-Scott, Peter; Nuñez, Martin A; Pauchard, Aníbal; Pyšek, Petr; Vítková, Michaela; Maxwell, Bruce D

    2015-01-01

    Terrestrial invasive plants are a global problem and are becoming ubiquitous components of most ecosystems. They are implicated in altering disturbance regimes, reducing biodiversity, and changing ecosystem function, sometimes in profound and irreversible ways. However, the ecological impacts of most invasive plants have not been studied experimentally, and most research to date focuses on few types of impacts, which can vary greatly among studies. Thus, our knowledge of existing ecological impacts ascribed to invasive plants is surprisingly limited in both breadth and depth. Our aim was to propose a standard methodology for quantifying baseline ecological impact that, in theory, is scalable to any terrestrial plant invader (e.g., annual grasses to trees) and any invaded system (e.g., grassland to forest). The Global Invader Impact Network (GIIN) is a coordinated distributed experiment composed of an observational and manipulative methodology. The protocol consists of a series of plots located in (1) an invaded area; (2) an adjacent removal treatment within the invaded area; and (3) a spatially separate uninvaded area thought to be similar to pre-invasion conditions of the invaded area. A standardized and inexpensive suite of community, soil, and ecosystem metrics are collected allowing broad comparisons among measurements, populations, and species. The method allows for one-time comparisons and for long-term monitoring enabling one to derive information about change due to invasion over time. Invader removal plots will also allow for quantification of legacy effects and their return rates, which will be monitored for several years. GIIN uses a nested hierarchical scale approach encompassing multiple sites, regions, and continents. Currently, GIIN has network members in six countries, with new members encouraged. To date, study species include representatives of annual and perennial grasses; annual and perennial forbs; shrubs; and trees. The goal of the GIIN framework is to create a standard yet flexible platform for understanding the ecological impacts of invasive plants, allowing both individual and synthetic analyses across a range of taxa and ecosystems. If broadly adopted, this standard approach will offer unique insight into the ecological impacts of invasive plants at local, regional, and global scales. PMID:26306173

  20. CD40 triggering induces strong cytotoxic T lymphocyte responses to heat-killed Staphylococcus aureus immunization in mice: a new vaccine strategy for staphylococcal mastitis.

    PubMed

    Wallemacq, Hugues; Bedoret, Denis; Pujol, Julien; Desmet, Christophe; Drion, Pierre-Vincent; Farnir, Frédéric; Mainil, Jacques; Lekeux, Pierre; Bureau, Fabrice; Fiévez, Laurence

    2012-03-01

    Staphylococcus (S.) aureus is a major pathogen involved in chronic bovine mastitis. Staphylococcal mastitis is difficult to control due to the ability of S. aureus to invade and survive within host cells. We therefore postulated that induction of CD8(+) cytotoxic T lymphocyte (CTL) responses leading to destruction of infected cells could help in the control of S. aureus mastitis. We demonstrate that immunization of mice with heat-killed S. aureus together with agonistic anti-CD40 monoclonal antibodies elicits strong CTL responses capable of reducing the severity of subsequent staphylococcal mastitis. Our study shows promise for CTL-dependent vaccination against S. aureus mastitis. PMID:22285272

  1. Impacts of invading alien plant species on water flows at stand and catchment scales

    PubMed Central

    Le Maitre, D. C.; Gush, M. B.; Dzikiti, S.

    2015-01-01

    There have been many studies of the diverse impacts of invasions by alien plants but few have assessed impacts on water resources. We reviewed the information on the impacts of invasions on surface runoff and groundwater resources at stand to catchment scales and covering a full annual cycle. Most of the research is South African so the emphasis is on South Africa's major invaders with data from commercial forest plantations where relevant. Catchment studies worldwide have shown that changes in vegetation structure and the physiology of the dominant plant species result in changes in surface runoff and groundwater discharge, whether they involve native or alien plant species. Where there is little change in vegetation structure [e.g. leaf area (index), height, rooting depth and seasonality] the effects of invasions generally are small or undetectable. In South Africa, the most important woody invaders typically are taller and deeper rooted than the native species. The impacts of changes in evaporation (and thus runoff) in dryland settings are constrained by water availability to the plants and, thus, by rainfall. Where the dryland invaders are evergreen and the native vegetation (grass) is seasonal, the increases can reach 300–400 mm/year. Where the native vegetation is evergreen (shrublands) the increases are ∼200–300 mm/year. Where water availability is greater (riparian settings or shallow water tables), invading tree water-use can reach 1.5–2.0 times that of the same species in a dryland setting. So, riparian invasions have a much greater impact per unit area invaded than dryland invasions. The available data are scattered and incomplete, and there are many gaps and issues that must be addressed before a thorough understanding of the impacts at the site scale can be gained and used in extrapolating to watershed scales, and in converting changes in flows to water supply system yields. PMID:25935861

  2. [From persistence to symbiosis of microorganisms].

    PubMed

    Bukharin, O V

    2012-01-01

    Primary results of study of problem of microorganism persistence over the last 2 decades on 7 all-Russian conferences in Orenburg are examined in the article. Milestones of both fundamental research and practically significant studies are designated, the role of persistent potential of microorganisms in infectious pathology is evaluated. The emerging turn of studies from persistence to symbiosis is consonant with the idea of international project "Human microbiom" and allows to use the persistent potential of microorganisms as one of the instruments of resolving issues of infectology. PMID:22937697

  3. Noether versus Killing symmetry of conformally flat Friedmann metric

    NASA Astrophysics Data System (ADS)

    Bokhari, Ashfaque H.; Kara, A. H.

    2007-12-01

    In a recent study Noether symmetries of some static spacetime metrics in comparison with Killing vectors of corresponding spacetimes were studied. It was shown that Noether symmetries provide additional conservation laws that are not given by Killing vectors. In an attempt to understand how Noether symmetries compare with conformal Killing vectors, we find the Noether symmetries of the flat Friedmann cosmological model. We show that the conformally transformed flat Friedman model admits additional conservation laws not given by the Killing or conformal Killing vectors. Inter alia, these additional conserved quantities provide a mechanism to twice reduce the geodesic equations via the associated Noether symmetries.

  4. Antimicrobial Photodynamic Therapy to Kill Gram-negative Bacteria

    PubMed Central

    Sperandio, Felipe F; Huang, Ying-Ying; Hamblin, Michael R

    2013-01-01

    Antimicrobial photodynamic therapy (PDT) or photodynamic inactivation (PDI) is a new promising strategy to eradicate pathogenic microorganisms such as Gram-positive and Gram-negative bacteria, yeasts and fungi. The search for new approaches that can kill bacteria but do not induce the appearance of undesired drug-resistant strains suggests that PDT may have advantages over traditional antibiotic therapy. PDT is a non-thermal photochemical reaction that involves the simultaneous presence of visible light, oxygen and a dye or photosensitizer (PS). Several PS have been studied for their ability to bind to bacteria and efficiently generate reactive oxygen species (ROS) upon photostimulation. ROS are formed through type I or II mechanisms and may inactivate several classes of microbial cells including Gram-negative bacteria such as Pseudomonas aeruginosa, which are typically characterized by an impermeable outer cell membrane that contains endotoxins and blocks antibiotics, dyes, and detergents, protecting the sensitive inner membrane and cell wall. This review covers significant peer-reviewed articles together with US and World patents that were filed within the past few years and that relate to the eradication of Gram-negative bacteria via PDI or PDT. It is organized mainly according to the nature of the PS involved and includes natural or synthetic food dyes; cationic dyes such as methylene blue and toluidine blue; tetrapyrrole derivatives such as phthalocyanines, chlorins, porphyrins, chlorophyll and bacteriochlorophyll derivatives; functionalized fullerenes; nanoparticles combined with different PS; other formulations designed to target PS to bacteria; photoactive materials and surfaces; conjugates between PS and polycationic polymers or antibodies; and permeabilizing agents such as EDTA, PMNP and CaCl2. The present review also covers the different laboratory animal models normally used to treat Gram-negative bacterial infections with antimicrobial PDT. PMID:23550545

  5. Antimicrobial photodynamic therapy to kill Gram-negative bacteria.

    PubMed

    Sperandio, Felipe F; Huang, Ying-Ying; Hamblin, Michael R

    2013-08-01

    Antimicrobial photodynamic therapy (PDT) or photodynamic inactivation (PDI) is a new promising strategy to eradicate pathogenic microorganisms such as Gram-positive and Gram-negative bacteria, yeasts and fungi. The search for new approaches that can kill bacteria but do not induce the appearance of undesired drug-resistant strains suggests that PDT may have advantages over traditional antibiotic therapy. PDT is a non-thermal photochemical reaction that involves the simultaneous presence of visible light, oxygen and a dye or photosensitizer (PS). Several PS have been studied for their ability to bind to bacteria and efficiently generate reactive oxygen species (ROS) upon photo-stimulation. ROS are formed through type I or II mechanisms and may inactivate several classes of microbial cells including Gram-negative bacteria such as Pseudomonas aeruginosa, which are typically characterized by an impermeable outer cell membrane that contains endotoxins and blocks antibiotics, dyes, and detergents, protecting the sensitive inner membrane and cell wall. This review covers significant peer-reviewed articles together with US and World patents that were filed within the past few years and that relate to the eradication of Gram-negative bacteria via PDI or PDT. It is organized mainly according to the nature of the PS involved and includes natural or synthetic food dyes; cationic dyes such as methylene blue and toluidine blue; tetrapyrrole derivatives such as phthalocyanines, chlorins, porphyrins, chlorophyll and bacteriochlorophyll derivatives; functionalized fullerenes; nanoparticles combined with different PS; other formulations designed to target PS to bacteria; photoactive materials and surfaces; conjugates between PS and polycationic polymers or antibodies; and permeabilizing agents such as EDTA, PMNP and CaCl₂. The present review also covers the different laboratory animal models normally used to treat Gram-negative bacterial infections with antimicrobial PDT. PMID:23550545

  6. Dynamic kill: controlling wild wells a new way

    SciTech Connect

    Blount, E.M.; Soeiinah, E.

    1981-10-01

    Dynamic kill describes a technique for terminating a blowout utilizing flowing frictional pressure to supplement the hydrostatic pressure of the kill fluid being injected through the relief well and up the blowing well. Therefore, a lighter kill fluid such as water can be implemented. The objective is to allow a blowout to be killed without breaking down the formation so the maximum amount of fluid can be circulated through the relief well by not losing fluid to a fractured formation. This allows optimum control during the kill operation and stable communication between the two wells. By allowing more fluid to be applied to the kill through one relief well, dynamic kill also increases the probability that one relief well will be sufficient. When the well is dynamically dead, the initial kill fluid, which will usually be too light to hold the well dead in a static condition, is replaced with a heavier kill mud. In fact, three weights of mud may be required to allow control during the transition from low density initial dynamic kill mud to heavy final kill mud. 5 refs.

  7. Mechanisms of contact-mediated killing of yeast cells on dry metallic copper surfaces.

    PubMed

    Quaranta, Davide; Krans, Travis; Espírito Santo, Christophe; Elowsky, Christian G; Domaille, Dylan W; Chang, Christopher J; Grass, Gregor

    2011-01-01

    Surfaces made of copper or its alloys have strong antimicrobial properties against a wide variety of microorganisms. However, the molecular mode of action responsible for the antimicrobial efficacy of metallic copper is not known. Here, we show that dry copper surfaces inactivate Candida albicans and Saccharomyces cerevisiae within minutes in a process called contact-mediated killing. Cellular copper ion homeostasis systems influenced the kinetics of contact-mediated killing in both organisms. Deregulated copper ion uptake through a hyperactive S. cerevisiae Ctr1p (ScCtr1p) copper uptake transporter in Saccharomyces resulted in faster inactivation of mutant cells than of wild-type cells. Similarly, lack of the C. albicans Crp1p (CaCrp1p) copper-efflux P-type ATPase or the metallothionein CaCup1p caused more-rapid killing of Candida mutant cells than of wild-type cells. Candida and Saccharomyces took up large quantities of copper ions as soon as they were in contact with copper surfaces, as indicated by inductively coupled plasma mass spectroscopy (ICP-MS) analysis and by the intracellular copper ion-reporting dye coppersensor-1. Exposure to metallic copper did not cause lethality through genotoxicity, deleterious action on a cell's genetic material, as indicated by a mutation assay with Saccharomyces. Instead, toxicity mediated by metallic copper surfaces targeted membranes in both yeast species. With the use of Live/Dead staining, onset of rapid and extensive cytoplasmic membrane damage was observed in cells from copper surfaces. Fluorescence microscopy using the indicator dye DiSBaC(2)(3) indicated that cell membranes were depolarized. Also, during contact-mediated killing, vacuoles first became enlarged and then disappeared from the cells. Lastly, in metallic copper-stressed yeasts, oxidative stress in the cytoplasm and in mitochondria was elevated. PMID:21097600

  8. Mechanisms of Contact-Mediated Killing of Yeast Cells on Dry Metallic Copper Surfaces▿

    PubMed Central

    Quaranta, Davide; Krans, Travis; Santo, Christophe Espírito; Elowsky, Christian G.; Domaille, Dylan W.; Chang, Christopher J.; Grass, Gregor

    2011-01-01

    Surfaces made of copper or its alloys have strong antimicrobial properties against a wide variety of microorganisms. However, the molecular mode of action responsible for the antimicrobial efficacy of metallic copper is not known. Here, we show that dry copper surfaces inactivate Candida albicans and Saccharomyces cerevisiae within minutes in a process called contact-mediated killing. Cellular copper ion homeostasis systems influenced the kinetics of contact-mediated killing in both organisms. Deregulated copper ion uptake through a hyperactive S. cerevisiae Ctr1p (ScCtr1p) copper uptake transporter in Saccharomyces resulted in faster inactivation of mutant cells than of wild-type cells. Similarly, lack of the C. albicans Crp1p (CaCrp1p) copper-efflux P-type ATPase or the metallothionein CaCup1p caused more-rapid killing of Candida mutant cells than of wild-type cells. Candida and Saccharomyces took up large quantities of copper ions as soon as they were in contact with copper surfaces, as indicated by inductively coupled plasma mass spectroscopy (ICP-MS) analysis and by the intracellular copper ion-reporting dye coppersensor-1. Exposure to metallic copper did not cause lethality through genotoxicity, deleterious action on a cell's genetic material, as indicated by a mutation assay with Saccharomyces. Instead, toxicity mediated by metallic copper surfaces targeted membranes in both yeast species. With the use of Live/Dead staining, onset of rapid and extensive cytoplasmic membrane damage was observed in cells from copper surfaces. Fluorescence microscopy using the indicator dye DiSBaC2(3) indicated that cell membranes were depolarized. Also, during contact-mediated killing, vacuoles first became enlarged and then disappeared from the cells. Lastly, in metallic copper-stressed yeasts, oxidative stress in the cytoplasm and in mitochondria was elevated. PMID:21097600

  9. Copper Reduction and Contact Killing of Bacteria by Iron Surfaces

    PubMed Central

    Mathews, Salima; Kumar, Ranjeet

    2015-01-01

    The well-established killing of bacteria by copper surfaces, also called contact killing, is currently believed to be a combined effect of bacterial contact with the copper surface and the dissolution of copper, resulting in lethal bacterial damage. Iron can similarly be released in ionic form from iron surfaces and would thus be expected to also exhibit contact killing, although essentially no contact killing is observed by iron surfaces. However, we show here that the exposure of bacteria to iron surfaces in the presence of copper ions results in efficient contact killing. The process involves reduction of Cu2+ to Cu+ by iron; Cu+ has been shown to be considerably more toxic to cells than Cu2+. The specific Cu+ chelator, bicinchoninic acid, suppresses contact killing by chelating the Cu+ ions. These findings underline the importance of Cu+ ions in the contact killing process and infer that iron-based alloys containing copper could provide novel antimicrobial materials. PMID:26150470

  10. Copper Reduction and Contact Killing of Bacteria by Iron Surfaces.

    PubMed

    Mathews, Salima; Kumar, Ranjeet; Solioz, Marc

    2015-09-01

    The well-established killing of bacteria by copper surfaces, also called contact killing, is currently believed to be a combined effect of bacterial contact with the copper surface and the dissolution of copper, resulting in lethal bacterial damage. Iron can similarly be released in ionic form from iron surfaces and would thus be expected to also exhibit contact killing, although essentially no contact killing is observed by iron surfaces. However, we show here that the exposure of bacteria to iron surfaces in the presence of copper ions results in efficient contact killing. The process involves reduction of Cu(2+) to Cu(+) by iron; Cu(+) has been shown to be considerably more toxic to cells than Cu(2+). The specific Cu(+) chelator, bicinchoninic acid, suppresses contact killing by chelating the Cu(+) ions. These findings underline the importance of Cu(+) ions in the contact killing process and infer that iron-based alloys containing copper could provide novel antimicrobial materials. PMID:26150470

  11. Geometry of Killing spinors in neutral signature

    NASA Astrophysics Data System (ADS)

    Klemm, Dietmar; Nozawa, Masato

    2015-09-01

    We classify the supersymmetric solutions of minimal N = 2 gauged supergravity in four dimensions with neutral signature. They are distinguished according to the sign of the cosmological constant and whether the vector field constructed as a bilinear of the Killing spinor is null or non-null. In neutral signature the bilinear vector field can be spacelike, which is a new feature not arising in Lorentzian signature. In the {{Λ }}\\lt 0 non-null case, the canonical form of the metric is described by a fibration over a three-dimensional base space that has {{U}}(1) holonomy with torsion. We find that a generalized monopole equation determines the twist of the bilinear Killing field, which is reminiscent of an Einstein-Weyl structure. If, moreover, the electromagnetic field strength is self-dual, one gets the Kleinian signature analogue of the Przanowski-Tod class of metrics, namely a pseudo-hermitian spacetime determined by solutions of the continuous Toda equation, conformal to a scalar-flat pseudo-Kähler manifold, and admitting in addition a charged conformal Killing spinor. In the {{Λ }}\\lt 0 null case, the supersymmetric solutions define an integrable null Kähler structure. In the {{Λ }}\\gt 0 non-null case, the manifold is a fibration over a Lorentzian Gauduchon-Tod base space. Finally, in the {{Λ }}\\gt 0 null class, the metric is contained in the Kundt family, and it turns out that the holonomy is reduced to {Sim}(1)× {Sim}(1). There appear no self-dual solutions in the null class for either sign of the cosmological constant.

  12. Killing-Yano forms and Killing tensors on a warped space

    NASA Astrophysics Data System (ADS)

    Krtouš, Pavel; KubizÅák, David; Kolář, Ivan

    2016-01-01

    We formulate several criteria under which the symmetries associated with the Killing and Killing-Yano tensors on the base space can be lifted to the symmetries of the full warped geometry. The procedure is explicitly illustrated on several examples, providing new prototypes of spacetimes admitting such tensors. In particular, we study a warped product of two Kerr-NUT-(A)dS spacetimes and show that it gives rise to a new class of highly symmetric vacuum (with a cosmological constant) black hole solutions that inherit many of the properties of the Kerr-NUT-(A)dS geometry.

  13. Targeting the Checkpoint to Kill Cancer Cells

    PubMed Central

    Benada, Jan; Macurek, Libor

    2015-01-01

    Cancer treatments such as radiotherapy and most of the chemotherapies act by damaging DNA of cancer cells. Upon DNA damage, cells stop proliferation at cell cycle checkpoints, which provides them time for DNA repair. Inhibiting the checkpoint allows entry to mitosis despite the presence of DNA damage and can lead to cell death. Importantly, as cancer cells exhibit increased levels of endogenous DNA damage due to an excessive replication stress, inhibiting the checkpoint kinases alone could act as a directed anti-cancer therapy. Here, we review the current status of inhibitors targeted towards the checkpoint effectors and discuss mechanisms of their actions in killing of cancer cells. PMID:26295265

  14. The killing efficiency of soft iron shot

    USGS Publications Warehouse

    Andrews, R.; Longcore, J.R.

    1969-01-01

    A cooperative research effort between the ammunition industry and the Bureau of Sport Fisheries and Wildlife is aimed at finding a suitable non-toxic substitute for lead shot. A contract study by an independent research organization evaluated ways of coating or detoxifying lead shot or replacing it with another metal. As a result of that study, the only promising candidate is soft iron. Previous tests of hard iron shot had suggested that its killing effectiveness was poor at longer ranges due to the lower density. In addition, its hardness caused excessive damage to shotgun barrels. A unique, automated shooting facility was constructed at the Patuxent Wildlife Research Center to test the killing effectiveness of soft iron shot under controlled conditions. Tethered game-farm mallards were transported across a shooting point in a manner simulating free flight. A microswitch triggered a mounted shotgun so that each shot was 'perfect.' A soft iron shot, in Number 4 size, was produced by the ammunition industry and loaded in 12-gauge shells to give optimum ballistic performance. Commercial loads of lead shot in both Number 4 and Number 6 size were used for comparison. A total of 2,010 ducks were shot at ranges of 30 to 65 yards and at broadside and head-on angles in a statistically designed procedure. The following data were recorded for each duck: time until death, broken wing or leg bones, and number of embedded shot. Those ducks not killed outright were held for 10 days. From these data, ducks were categorized as 'probably bagged,' 'probably lost cripples,' or survivors. The test revealed that the killing effectiveness of this soft iron shot was superior to its anticipated performance and close to that obtained with commercial lead loads containing an equal number of pellets. Bagging a duck, in terms of rapid death or broken wing, was primarily dependent on the probability of a shot striking that vital area, and therefore a function of range. There was no indication that iron shot would result in greater crippling loss. Despite the apparent effectiveness of this iron shot, transition to its use in waterfowl hunting is not now possible. The sample used for this test was produced by a laboratory procedure that is unsuitable for manufacture. There is no process for producing soft iron shot in the quantities needed. Industry is doing its best to resolve this problem.

  15. PARTICLE-ASSOCIATED MICROORGANISMS IN STORMWATER RUNOFF

    EPA Science Inventory

    This research investigated the effects of blending and chemical addition before analysis of the concentration of microorganisms in stormwater runoff to determine whether clumped or particle-associated organisms play a significant role. All organisms, except for Escherichia coli, ...

  16. Mass Spectrometry for Rapid Characterization of Microorganisms

    NASA Astrophysics Data System (ADS)

    Demirev, Plamen A.; Fenselau, Catherine

    2008-07-01

    Advances in instrumentation, proteomics, and bioinformatics have contributed to the successful applications of mass spectrometry (MS) for detection, identification, and classification of microorganisms. These MS applications are based on the detection of organism-specific biomarker molecules, which allow differentiation between organisms to be made. Intact proteins, their proteolytic peptides, and nonribosomal peptides have been successfully utilized as biomarkers. Sequence-specific fragments for biomarkers are generated by tandem MS of intact proteins or proteolytic peptides, obtained after, for instance, microwave-assisted acid hydrolysis. In combination with proteome database searching, individual biomarker proteins are unambiguously identified from their tandem mass spectra, and from there the source microorganism is also identified. Such top-down or bottom-up proteomics approaches permit rapid, sensitive, and confident characterization of individual microorganisms in mixtures and are reviewed here. Examples of MS-based functional assays for detection of targeted microorganisms, e.g., Bacillus anthracis, in environmental or clinically relevant backgrounds are also reviewed.

  17. Detection of microorganisms using terahertz metamaterials

    NASA Astrophysics Data System (ADS)

    Park, S. J.; Hong, J. T.; Choi, S. J.; Kim, H. S.; Park, W. K.; Han, S. T.; Park, J. Y.; Lee, S.; Kim, D. S.; Ahn, Y. H.

    2014-05-01

    Microorganisms such as fungi and bacteria cause many human diseases and therefore rapid and accurate identification of these substances is essential for effective treatment and prevention of further infections. In particular, contemporary microbial detection technique is limited by the low detection speed which usually extends over a couple of days. Here we demonstrate that metamaterials operating in the terahertz frequency range shows promising potential for use in fabricating the highly sensitive and selective microbial sensors that are capable of high-speed on-site detection of microorganisms in both ambient and aqueous environments. We were able to detect extremely small amounts of the microorganisms, because their sizes are on the same scale as the micro-gaps of the terahertz metamaterials. The resonant frequency shift of the metamaterials was investigated in terms of the number density and the dielectric constants of the microorganisms, which was successfully interpreted by the change in the effective dielectric constant of a gap area.

  18. Detection of microorganisms using terahertz metamaterials

    PubMed Central

    Park, S. J.; Hong, J. T.; Choi, S. J.; Kim, H. S.; Park, W. K.; Han, S. T.; Park, J. Y.; Lee, S.; Kim, D. S.; Ahn, Y. H.

    2014-01-01

    Microorganisms such as fungi and bacteria cause many human diseases and therefore rapid and accurate identification of these substances is essential for effective treatment and prevention of further infections. In particular, contemporary microbial detection technique is limited by the low detection speed which usually extends over a couple of days. Here we demonstrate that metamaterials operating in the terahertz frequency range shows promising potential for use in fabricating the highly sensitive and selective microbial sensors that are capable of high-speed on-site detection of microorganisms in both ambient and aqueous environments. We were able to detect extremely small amounts of the microorganisms, because their sizes are on the same scale as the micro-gaps of the terahertz metamaterials. The resonant frequency shift of the metamaterials was investigated in terms of the number density and the dielectric constants of the microorganisms, which was successfully interpreted by the change in the effective dielectric constant of a gap area. PMID:24832607

  19. The adaptive value of remnant native plants in invaded communities: an example from the Great Basin.

    PubMed

    Leger, Elizabeth A

    2008-07-01

    Changes in the species composition of biotic communities may alter patterns of natural selection occurring within them. Native perennial grass species in the Intermountain West are experiencing a shift in the composition of interspecific competitors from primarily perennial species to an exotic, annual grass. Thus traits that confer an advantage to perennial grasses in the presence of novel annual competitors may evolve in invaded communities. Here I show that such traits are apparent in populations of a native perennial grass, big squirreltail (Elymus multisetus M.E. Jones), exposed to cheatgrass (Bromus tectorum L.) competitors. Dormant big squirreltail plants were collected from cheatgrass-invaded and uninvaded sites near Bordertown, California, USA, a mid-elevation (1600 m) sagebrush community, and transplanted into pots in a greenhouse. Individual plants were split into equal halves. One half was grown with competition from cheatgrass, and the other half was grown without competition. Plants collected from invaded sites responded more quickly to watering, growing more leaves in the first 10 days after transplanting. In addition, big squirreltail plants collected from invaded areas experienced a smaller decrease in plant size when grown with competition than did plants collected from uninvaded areas. Accordingly, while there were fewer big squirreltail individuals in the invaded sites, they were more competitive with cheatgrass than were the more abundant conspecifics in nearby uninvaded areas. It is possible that annual grasses were the selective force that caused these population differences, which may contribute to the long-term persistence of the native populations. While it is tempting to restore degraded areas to higher densities of natives (usually done by bringing in outside seed material), such actions may impede long-term adaptation to new conditions by arresting or reversing the direction of ongoing natural selection in the resident population. If hot spots of rapid evolutionary change can be identified within invaded systems, these areas should be managed to promote desirable change and could serve as possible sources of restoration material or reveal traits that should be prioritized during the development of restoration seed material. PMID:18686583

  20. Enhanced oil recovery using denitrifying microorganisms

    SciTech Connect

    Sperl, G.T.; Sperl, P.L.

    1991-09-03

    This patent describes a method of microbial enhanced oil recovery. It comprises the step of introducing, into a carbonate-containing rock formation that defines an anaerobic environment, denitrifying microorganisms, an aqueous liquid carrier and a nonoxygen electron accepter, such that the microorganism reduce the non-oxygen electron accepter in the presence of a sulfur-containing compound and produce sulfuric acid, which dissolves carbonate in the rock formation to release oil.

  1. Automated systems for identification of microorganisms.

    PubMed Central

    Stager, C E; Davis, J R

    1992-01-01

    Automated instruments for the identification of microorganisms were introduced into clinical microbiology laboratories in the 1970s. During the past two decades, the capabilities and performance characteristics of automated identification systems have steadily progressed and improved. This article explores the development of the various automated identification systems available in the United States and reviews their performance for identification of microorganisms. Observations regarding deficiencies and suggested improvements for these systems are provided. PMID:1498768

  2. The ability of insect-killing fungi to kill pecan aphids under laboratory conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is need for efficacious biocontrol agents for pecan aphids in commercial orchards. We determined the virulence (killing power) of several beneficial fungi to pecan aphids. We tested three species (kinds) of fungi: 1) Isaria fumosorosea (two strains of this species were tested: ARSEF 3581 a...

  3. Neutrophils exert protection in the early tuberculous granuloma by oxidative killing of mycobacteria phagocytosed from infected macrophages.

    PubMed

    Yang, Chao-Tsung; Cambier, C J; Davis, J Muse; Hall, Christopher J; Crosier, Philip S; Ramakrishnan, Lalita

    2012-09-13

    Neutrophils are typically the first responders in host defense against invading pathogens, which they destroy by both oxidative and nonoxidative mechanisms. However, despite a longstanding recognition of neutrophil presence at disease sites in tuberculosis, their role in defense against mycobacteria is unclear. Here we exploit the genetic tractability and optical transparency of zebrafish to monitor neutrophil behavior and its consequences during infection with Mycobacterium marinum, a natural fish pathogen. In contrast to macrophages, neutrophils do not interact with mycobacteria at initial infection sites. Neutrophils are subsequently recruited to the nascent granuloma in response to signals from dying infected macrophages within the granuloma, which they phagocytose. Some neutrophils then rapidly kill the internalized mycobacteria through NADPH oxidase-dependent mechanisms. Our results provide a mechanistic link to the observed patterns of neutrophils in human tuberculous granulomas and the susceptibility of humans with chronic granulomatous disease to mycobacterial infection. PMID:22980327

  4. Resection of a Catecholamine-Elaborating Retroperitoneal Paraganglioma Invading the Inferior Vena Cava

    PubMed Central

    Mannina, E. M.; Xiong, Z.; Self, R.; Kandil, E.

    2014-01-01

    Paragangliomas are rare tumors originating outside of the adrenal medulla which can be associated with catecholamine secretion or mass effect, one of which typically leads to their discovery. The differences between these tumors and traditional intra-adrenal pheochromocytomas are a subject of recent investigations. Standard of care therapy is medical management and surgical resection of the tumor. When tumors are biochemically active, medical optimization of the autonomic nervous system is a critical component to a safe, definitive resection. Tumors arising in the retroperitoneum present technical challenges for the surgeon as they are often large and difficult to access, making an oncologic resection much more difficult. Lastly, these tumors are mostly benign and rarely invade adjacent structures—an operative finding not always predicted by preoperative imaging—which, if present, adds significant complexity and risk to the resection. A case illustrating these challenges in the management of a biochemically active retroperitoneal paraganglioma invading the inferior vena cava follows. PMID:25610696

  5. Attaching and effacing enteropathogenic Escherichia coli O18ab invades epithelial cells and causes persistent diarrhea.

    PubMed Central

    Scaletsky, I C; Pedroso, M Z; Fagundes-Neto, U

    1996-01-01

    A case of persistent diarrhea following Escherichia coli O18ab gastroenteritis is reported. Electron microscopy of a biopsy of the small intestine showed effacement of the brush border, attachment of bacteria to the epithelial cells with pedestal formation, and bacteria within the enterocytes. The bacterial isolate was an enteropathogenic E. coli isolate which did not contain the adherence factor (EAF) but possessed the attaching-effacing eae gene, was able to invade HeLa cells in a gentamicin invasion assay, and also invaded rabbit intestinal cells. Results suggest that E. coli organisms of the O18ab serotype may cause diarrhea by an as yet unknown pathogenic mechanism, involving attaching to and effacing of enterocytes followed by invasion of the epithelial cells. PMID:8890257

  6. Effect on microorganisms of volatile compounds released from germinating seeds.

    PubMed

    Schenck, S; Stotzky, G

    1975-10-01

    Volatile compounds evolved from germinating seeds of slash pine, bean, cabbage, corn, cucumber, and pea were evaluated for their ability to support growth of microorganisms in liquid mineral salts media lacking a carbon source. Growth of eight bacteria was measured turbidimetrically and of six fungi as dry weight of mycelium. Volatiles caused increased growth of Pseudomonas fluorescens, Bacillus cereus, Erwinia carotovora, Agrobacterium tumefaciens, A. radiobacter, Rhizobium japonicum, Mucor mucedo, Fusarium oxysporum f. conglutinans, Trichoderma viride, and Penicillium vermiculatum but not of Sarcina lutea, Serratia marcescens, Chaetomium globosum, or Schizophyllum commune. Spores of Trichoderma viride showed higher germination in the presence of volatiles. Effects on growth were apparent only during the first 3 or 4 days after planting the seeds. Killed or dried seeds had no effect. The volatiles did not support microbial growth in the absence of nitrogen nor did they supply growth factors. Passing volatiles through KMnO4 or hydrazone reduced growth of the bacteria, indicating that oxidizable organic compounds, primarily aldehydes, were the active components. The volatiles were not absorbed by sterile soil, clay minerals, or water, but they were absorbed by non-steril soil and activated charcoal. PMID:1201509

  7. Effect of Microorganisms on In Situ Uranium Mining

    PubMed Central

    Yates, Marylynn V.; Brierley, James A.; Brierley, Corale L.; Follin, Steven

    1983-01-01

    The extraction of some metal values, e.g., uranium or copper, may be accomplished by using solutions to remove metals from ore bodies without practicing conventional mining. This process is referred to as in situ leaching and has been used industrially to recover uranium. The growth of microbial populations during in situ leaching is believed to be one of the causes of flow path plugging in the ore body, which results in decreased uranium production. Leach solution and solid samples from well casings and submersible pumps were collected from an in situ mining operation experiencing plugging problems. Bacillus sp., Micrococcus sp., pseudomonads, and xanthomonads were isolated from these samples in concentrations of 105 CFU ml?1. A mixed culture of these organisms was inoculated into a uranium core specimen in the laboratory to assess the role of microbes in the plugging problem. A one-third decrease in permeability was effected in 16 days. Hydrogen peroxide (0.2 g liter?1) killed the microorganisms in the core and alleviated the plugging problem. Periodically injecting hydrogen peroxide into the ore body through the production wells may reduce microbial plugging problems. PMID:16346395

  8. Co-invaders: The effects of alien parasites on native hosts

    PubMed Central

    Lymbery, Alan J.; Morine, Mikayla; Kanani, Hosna Gholipour; Beatty, Stephen J.; Morgan, David L.

    2014-01-01

    We define co-introduced parasites as those which have been transported with an alien host to a new locality, outside of their natural range, and co-invading parasites as those which have been co-introduced and then spread to new, native hosts. Of 98 published studies of co-introductions, over 50% of hosts were freshwater fishes and 49% of parasites were helminths. Although we would expect parasites with simple, direct life cycles to be much more likely to be introduced and establish in a new locality, a substantial proportion (36%) of co-introductions were of parasites with an indirect life cycle. Seventy-eight per cent of co-introduced parasites were found in native host species and can therefore be classed as co-invaders. Host switching was equally common among parasites with direct and indirect life cycles. The magnitude of the threat posed to native species by co-invaders will depend, among other things, on parasite virulence. In 16 cases where co-introduced parasites have switched to native hosts and information was available on relative virulence, 14 (85%) were more virulent in native hosts than in the co-introduced alien host. We argue that this does not necessarily support the naïve host theory that co-invading parasites will have greater pathogenic effects in native hosts with which they have no coevolutionary history, but may instead be a consequence of the greater likelihood for parasites with lower virulence in their natural host to be co-introduced. PMID:25180161

  9. Helpful invaders: Can cane toads reduce the parasite burdens of native frogs?

    PubMed Central

    Nelson, Felicity B.L.; Brown, Gregory P.; Shilton, Catherine; Shine, Richard

    2015-01-01

    Many invading species have brought devastating parasites and diseases to their new homes, thereby imperiling native taxa. Potentially, though, invaders might have the opposite effect. If they take up parasites that otherwise would infect native taxa, but those parasites fail to develop in the invader, the introduced species might reduce parasite burdens of the native fauna. Similarly, earlier exposure to the other taxon's parasites might ‘prime’ an anuran's immune system such that it is then able to reject subsequent infection by its own parasite species. Field surveys suggest that lungworm counts in native Australian frogs decrease after the arrival of invasive cane toads (Rhinella marina), and laboratory studies confirm that native lungworm larvae enter, but do not survive in, the toads. In laboratory trials, we confirmed that the presence of anurans (either frogs or toads) in an experimental arena reduced uptake rates of lungworm larvae by anurans that were later added to the same arena. However, experimental exposure to lungworms from native frogs did not enhance a toad's ability to reject subsequent infection by its own lungworm species. PMID:26236630

  10. Cas6 is an endoribonuclease that generates guide RNAs for invader defense in prokaryotes

    SciTech Connect

    Carte, Jason; Wang, Ruiying; Li, Hong; Terns, Rebecca M.; Terns, Michael P.

    2010-11-09

    An RNA-based gene silencing pathway that protects bacteria and archaea from viruses and other genome invaders is hypothesized to arise from guide RNAs encoded by CRISPR loci and proteins encoded by the cas genes. CRISPR loci contain multiple short invader-derived sequences separated by short repeats. The presence of virus-specific sequences within CRISPR loci of prokaryotic genomes confers resistance against corresponding viruses. The CRISPR loci are transcribed as long RNAs that must be processed to smaller guide RNAs. Here we identified Pyrococcus furiosus Cas6 as a novel endoribonuclease that cleaves CRISPR RNAs within the repeat sequences to release individual invader targeting RNAs. Cas6 interacts with a specific sequence motif in the 5{prime} region of the CRISPR repeat element and cleaves at a defined site within the 3{prime} region of the repeat. The 1.8 angstrom crystal structure of the enzyme reveals two ferredoxin-like folds that are also found in other RNA-binding proteins. The predicted active site of the enzyme is similar to that of tRNA splicing endonucleases, and concordantly, Cas6 activity is metal-independent. cas6 is one of the most widely distributed CRISPR-associated genes. Our findings indicate that Cas6 functions in the generation of CRISPR-derived guide RNAs in numerous bacteria and archaea.

  11. Invader partitions ecological and evolutionary responses to above- and belowground herbivory.

    PubMed

    Huang, Wei; Carrillo, Juli; Ding, Jianqing; Siemann, Evan

    2012-11-01

    Interactions between above- and belowground herbivory may, affect plant performance and structure communities. Though many studies have documented interactions of invasive plants and.herbivores, none shows how above- and belowground herbivores interact to affect invasive plant performance. Here, in a common garden in China, we subjected genetically differentiated tallow trees (Triadica sebifera) from native (China) and invaded (United States) ranges to herbivory by aboveground adults and belowground larvae of a specialist beetle, Bikasha collaris. Overall, relative to plants from China, U.S. plants had greater total and aboveground mass, comparable belowground mass, lower resistance to both above- and belowground herbivory, and higher tolerance to aboveground herbivory only. Accordingly, aboveground adults had greater impacts on Chinese plants, but belowground larvae more strongly impacted U.S. plants. These results indicate that the invader may adopt an "aboveground first" strategy, allocating more resources aboveground in response to selection for increased competitive ability, which increases aboveground tolerance to herbivory. Furthermore, we found that adults facilitated larval success, and these feedbacks were stronger for U.S. plants, suggesting that aboveground feeding of adults may be associated with lower defenses and/or higher resources belowground in the invader. Therefore, plants may have evolved different responses to above- and belowground herbivory, which can affect invasion success and herbivore population dynamics. These findings may provide new insights for an effective biological control program against invasive plants. PMID:23236906

  12. Merging Two Strategies for Mixed-Sequence Recognition of Double-Stranded DNA: Pseudocomplementary Invader Probes.

    PubMed

    Anderson, Brooke A; Hrdlicka, Patrick J

    2016-04-15

    The development of molecular strategies that enable recognition of specific double-stranded DNA (dsDNA) regions has been a longstanding goal as evidenced by the emergence of triplex-forming oligonucleotides, peptide nucleic acids (PNAs), minor groove binding polyamides, and-more recently-engineered proteins such as CRISPR/Cas9. Despite this progress, an unmet need remains for simple hybridization-based probes that recognize specific mixed-sequence dsDNA regions under physiological conditions. Herein, we introduce pseudocomplementary Invader probes as a step in this direction. These double-stranded probes are chimeras between pseudocomplementary DNA (pcDNA) and Invader probes, which are activated for mixed-sequence dsDNA-recognition through the introduction of pseudocomplementary base pairs comprised of 2-thiothymine and 2,6-diaminopurine, and +1 interstrand zipper arrangements of intercalator-functionalized nucleotides, respectively. We demonstrate that certain pseudocomplementary Invader probe designs result in very efficient and specific recognition of model dsDNA targets in buffers of high ionic strength. These chimeric probes, therefore, present themselves as a promising strategy for mixed-sequence recognition of dsDNA targets for applications in molecular biology and nucleic acid diagnostics. PMID:26998918

  13. Invasional interference due to similar inter- and intraspecific competition between invaders may affect management.

    PubMed

    Rauschert, Emily Sofia Jalics; Shea, Katriona

    2012-07-01

    As the number of biological invasions increases, the potential for invader-invader interactions also rises. The effect of multiple invaders can be superadditive (invasional meltdown), additive, or subadditive (invasional interference); which of these situations occurs has critical implications for prioritization of management efforts. Carduus nutans and C. acanthoides, two congeneric invasive weeds, have a striking, segregated distribution in central Pennsylvania, U.S.A. Possible hypotheses for this pattern include invasion history and chance, direct competition, or negative interactions mediated by other species, such as shared pollinators. To explore the role of resource competition in generating this pattern, we conducted three related experiments using a response-surface design throughout the life cycles of two cohorts. Although these species have similar niche requirements, we found no differential response to competition between conspecifics vs. congeners. The response to combined density was relatively weak for both species. While direct competitive interactions do not explain the segregated distributional patterns of these two species, we predict that invasions of either species singly, or both species together, would have similar impacts. When prioritizing which areas to target to prevent the spread of one of the species, it is better to focus on areas as yet unaffected by its congener; where the congener is already present, invasional interference makes it unlikely that the net effect will change. PMID:22908701

  14. [Development of detection system of extraterrestrial microorganisms].

    PubMed

    Kawasaki, Y

    1994-06-01

    A noble method for the exploration of terrestrial and extraterrestrial soil microorganisms, especially targeted for Mars, has been developed. The method is based on the microscopic observation using fluorescence techniques. Microorganisms could be fluorescent by adsorption, enzymatic cleavage of extrinsic fluorescence chromophores such as acridine orange, ANS and SFDA, and also by intrinsic chromophores. The characteristic points of our fluorescence method are shown below. 1. The present method detected all the culturable cells tested (about 200 species from bacteria to eukaryofic cells). 2. Microorganisms in soil were much brighter than background fluorescence of soil. Cell shapes and location were clearly observed. 3. An esterase substatum SFDA, discriminated vital (reproductive) cells from dead. On the other hand, a membrane probe, ANS, detected both vital and dead cells. 3. Pre-treatment of cells with bleaching reagents improved the detection efficiency. Especially, this pretreatment was effecfive in Fungi with black chromophores. 4. Some anaerobic microorganisms such as methanogenic bacteria with intrinsic chromophores can be detected without stain. 5. Application of the technique to terrestrial soil revealed that more than 100 times larger cell density was obtained compared to the value obtained by the classic plate counting technique. Vertical distribution of microorganism of soil microorganisms from Mt. Shigayama showed that, at surface, cell density was small and maximum was shown below 15 cm from surface. 6. Some pre-biotic cell (cell like aggregates composed of amino acids) could be detected by SFDA or ANS. It can be concluded that the fluorescence technique is one of the most promising method for the exploration of extraterrestrial microorganisms. PMID:11542733

  15. Heterosigma bloom and associated fish kill

    USGS Publications Warehouse

    Hershberger, P.K.; Rensel, J.E.; Postel, J.R.; Taub, F.B.

    1997-01-01

    A bloom of the harmful marine phytoplankton, Heterosigma carterae occurred in upper Case Inlet, south Puget Sound, Washington in late September, 1994, correlating with the presence of at least 35 dead salmon. This marks the first time that this alga has been closely correlated with a wild fish kill; in the past it was thought to be associated with kills of penned fish at fish farms only. We were informed of the presence of a possible harmful algal bloom and dead salinois Ilear the town of Allyn on 27 September and a team was formed to investigate. We arrived at the Allyn waterfront at 17:30 hours the same day. Prior to our arrival, state agency personnel walked approximatcly two miles of shoreline from the powerlines north of the dock, to the mouth of Sherwood Creek and conducted the only official count of dead fish present along the shore consisting of 12 coho salmon (Oncorhynchus kisutch), 11 chum salmon (Oncorhynchus keta), 12 chinook salmon (Oncorhynchus tschawytscha), one flat fish, and one sculpin on the morning of 9/27. Since previous harmful blooms of Heterosigma have resultedin the majority of net penreared salmon sinking to the bottom of pens, and only approximately two miles of shoreline were sampled, it is suspected that many more exposed fish may have succumbed than were counted. Witnesses who explored the east side of the bay reported seeing many dead salmon there as well, but no counts were made. State agency personnel who observed the fish kill reported seeing “dying fish coming to the beach, gulping at the surface, trying to get out of the water” Scavengers were seen consuming the salmon carcasses; these included two harbor seals, a house cat, and Hymenopteran insects. None suffered any noticeable acute ill effects. Although precise cause of death has not been ascertained, visual inspection of the reproductive organs from a deceased male chum salmon found on the shore at Allyn confirmed that the fish was not yet reproductively mature and therefore did not die from completion of the spawning process.

  16. The eyeball killer: serial killings with postmortem globe enucleation.

    PubMed

    Coyle, Julie; Ross, Karen F; Barnard, Jeffrey J; Peacock, Elizabeth; Linch, Charles A; Prahlow, Joseph A

    2015-05-01

    Although serial killings are relatively rare, they can be the cause of a great deal of anxiety while the killer remains at-large. Despite the fact that the motivations for serial killings are typically quite complex, the psychological analysis of a serial killer can provide valuable insight into how and why certain individuals become serial killers. Such knowledge may be instrumental in preventing future serial killings or in solving ongoing cases. In certain serial killings, the various incidents have a variety of similar features. Identification of similarities between separate homicidal incidents is necessary to recognize that a serial killer may be actively killing. In this report, the authors present a group of serial killings involving three prostitutes who were shot to death over a 3-month period. Scene and autopsy findings, including the unusual finding of postmortem enucleation of the eyes, led investigators to recognize the serial nature of the homicides. PMID:25682709

  17. Using Chemoattractants to Lure Bacteria to Contact-Killing Surfaces.

    PubMed

    Jain, Rishabh; Faith, Nancy G; Milkowski, Andrew; Nelson, Kevin; Busche, David; Lynn, David M; Czuprynski, Charles J; Abbott, Nicholas L

    2016-05-01

    Antimicrobial surfaces with covalently attached biocidal functionalities only kill microbes that come into direct contact with the surfaces (contact-killing surfaces). Herein, the activity of contact-killing surfaces is shown to be enhanced by using gradients in the concentration of soluble chemoattractants (CAs) to attract bacteria to the surfaces. Two natural and nonbiocidal CAs (aspartate and glucose) were used to attract bacteria to model surfaces decorated with quaternary ammonium groups (known to kill bacteria that come into contact with them). These results demonstrate the killing of Escherichia coli and Salmonella typhimurium, two common pathogens, at levels 10- to 20-times greater than that of the native surfaces alone. This approach is general and provides new strategies for the design of active or dynamic contact-killing surfaces with enhanced antimicrobial activities. PMID:27059788

  18. Gradient conformal killing vectors and exact solutions

    NASA Astrophysics Data System (ADS)

    Daftardar, Varsha; Dadhich, Naresh

    1994-09-01

    We establish a connection between conformally related Einstein spaces and conformai killing vectors (CKV). We begin with the conformal map and prove that (a) under the conformal mapping¯g ik=Ω-2gik, the necessary and sufficient condition for the tracefree part of the Ricci tensor (S ik=Rik-(R/4)g ik) to remain invariant is thatΩ i is a CKV ofg ik, and (b) the most general form forΩ for conformally flat Einstein space, which is the de Sitter space, is composed of three terms each of which alone represents a flat space. The existence of gradient CKV (GCKV) is examined in relation to vacuum and perfect fluid spacetimes.

  19. f(R)-gravity from Killing tensors

    NASA Astrophysics Data System (ADS)

    Paliathanasis, Andronikos

    2016-04-01

    We consider f(R)-gravity in a Friedmann-Lemaître-Robertson-Walker spacetime with zero spatial curvature. We apply the Killing tensors of the minisuperspace in order to specify the functional form of f(R) and for the field equations to be invariant under Lie-Bäcklund transformations, which are linear in momentum (contact symmetries). Consequently, the field equations to admit quadratic conservation laws given by Noether’s theorem. We find three new integrable f(R)-models, for which, with the application of the conservation laws, we reduce the field equations to a system of two first-order ordinary differential equations. For each model we study the evolution of the cosmological fluid. We find that for each integrable model the cosmological fluid has an equation of state parameter, in which there is linear behavior in terms of the scale factor which describes the Chevallier, Polarski and Linder parametric dark energy model.

  20. Transverse conformal Killing forms on Kähler foliations

    NASA Astrophysics Data System (ADS)

    Jung, Seoung Dal

    2015-04-01

    On a closed, connected Riemannian manifold with a Kähler foliation of codimension q = 2 m, any transverse Killing r(≥ 2) -form is parallel (Jung and Jung, 2012). In this paper, we study transverse conformal Killing forms on Kähler foliations. In fact, if the foliation is minimal, then for any transverse conformal Killing r-form ϕ(2 ≤ r ≤ q - 2), Jϕ is parallel. Here J is defined in Section  4.

  1. Antibacterial activity of silver-killed bacteria: the "zombies" effect

    NASA Astrophysics Data System (ADS)

    Wakshlak, Racheli Ben-Knaz; Pedahzur, Rami; Avnir, David

    2015-04-01

    We report a previously unrecognized mechanism for the prolonged action of biocidal agents, which we denote as the zombies effect: biocidally-killed bacteria are capable of killing living bacteria. The concept is demonstrated by first killing Pseudomonas aeruginosa PAO1 with silver nitrate and then challenging, with the dead bacteria, a viable culture of the same bacterium: Efficient antibacterial activity of the killed bacteria is observed. A mechanism is suggested in terms of the action of the dead bacteria as a reservoir of silver, which, due to Le-Chatelier's principle, is re-targeted to the living bacteria. Langmuirian behavior, as well as deviations from it, support the proposed mechanism.

  2. Advancements in dynamic kill calculations for blowout wells

    SciTech Connect

    Kouba, G.E. . Production Fluids Div.); MacDougall, G.R. ); Schumacher, B.W. . Information Technology Dept.)

    1993-09-01

    This paper addresses the development, interpretation, and use of dynamic kill equations. To this end, three simple calculation techniques are developed for determining the minimum dynamic kill rate. Two techniques contain only single-phase calculations and are independent of reservoir inflow performance. Despite these limitations, these two methods are useful for bracketing the minimum flow rates necessary to kill a blowing well. For the third technique, a simplified mechanistic multiphase-flow model is used to determine a most-probable minimum kill rate.

  3. Killing forms and toric Sasaki-Einstein spaces

    NASA Astrophysics Data System (ADS)

    Slesar, Vladimir; Visinescu, Mihai; Vîlcu, Gabriel Eduard

    2014-11-01

    The construction of the special Killing forms on toric Sasaki-Einstein manifolds is presented. This goal is achieved using the interplay between complex coordinates of the Calabi-Yau metric cone and the special Killing forms on the toric Sasaki-Einstein space. As a concrete example, we present the complete set of special Killing forms on the five-dimensional Einstein-Sasaki Yp,q spaces. It is pointed out the existence of two additional special Killing forms associated with the complex holomorphic volume form of Calabi-Yau cone manifold.

  4. Killing spinors as a characterisation of rotating black hole spacetimes

    NASA Astrophysics Data System (ADS)

    Cole, Michael J.; Valiente Kroon, Juan A.

    2016-06-01

    We investigate the implications of the existence of Killing spinors in a spacetime. In particular, we show that in vacuum and electrovacuum a Killing spinor, along with some assumptions on the associated Killing vector in an asymptotic region, guarantees that the spacetime is locally isometric to the Kerr or Kerr–Newman solutions. We show that the characterisation of these spacetimes in terms of Killing spinors is an alternative expression of characterisation results of Mars (Kerr) and Wong (Kerr–Newman) involving restrictions on the Weyl curvature and matter content.

  5. Efficacy of spray application of chlorinated water in killing pathogenic bacteria on raw apples, tomatoes, and lettuce.

    PubMed

    Beuchat, L R; Nail, B V; Adler, B B; Clavero, M R

    1998-10-01

    Washing whole and cut produce by dipping or submerging in chlorinated water has a sanitizing effect, although reduction in microbial populations is minimal and is usually less than 100-fold. A study was undertaken to evaluate the efficacy of a spray application of chlorine in killing Salmonella, Escherichia coli O157:H7, Listeria monocytogenes, yeasts and molds, and total aerobic mesophilic microorganisms on whole apples, tomatoes, and lettuce leaves. Inoculated produce was treated (sprayed and then soaked) with water (control) or solutions containing 200 or 2,000 ppm of chlorine for 0, 1, 3, 5, or 10 min, rinsed with sterile water, and analyzed for populations (CFU/cm2) of target microorganisms. Compared to the control treatment, further reductions in numbers of pathogens of 0.35 to 2.30 log CFU/cm2 were achieved by treatment with chlorine. Chlorine was generally more effective at 2,000 ppm than at 200 ppm. Inactivation of microorganisms occurred essentially within 1 min after application of chlorine. These reductions are significant relative to populations of pathogenic microorganisms that may be present on produce. Spray application of chlorine to raw produce at food service or household levels may be a suitable, and more convenient, alternative to treatment by dipping or submersion. PMID:9798146

  6. Processing of coal with microorganisms. Final report

    SciTech Connect

    Olson, G.J.; Brinckman, F.E.; Iverson, W.P.

    1986-03-01

    A computer-assisted survey and evaluation of the international literature on microbial transformations of coal and relevant organic compounds was performed to identify candidate microorganisms and biological processes potentially applicable to coal bioprocessing. The vast majority of the literature on coal bioprocessing deals with desulfurization via pyrite removal, and some bioprocessing schemes have been proposed. Reports on organic sulfur and metals removal from coal have recently appeared. As yet unevaluated are systems for removal of other elements from coal such as oxygen and nitrogen. However, model substrates resembling certain important O and N functional groups in coal are degraded by microorganisms. These microorganisms could potentially be useful in coal bioprocessing. Our laboratory results suggest that a strain of Bacillus, capable of vanillic acid decarboxylation, may remove carboxyl groups from coal. We were not able to confirm literature reports on organic S removal from coal by Sulfolobus, or on coal liquefaction by certain fungi. 90 refs., 4 figs., 3 tabs.

  7. Biosurfactants, bioemulsifiers and exopolysaccharides from marine microorganisms.

    PubMed

    Satpute, Surekha K; Banat, Ibrahim M; Dhakephalkar, Prashant K; Banpurkar, Arun G; Chopade, Balu A

    2010-01-01

    Marine biosphere offers wealthy flora and fauna, which represents a vast natural resource of imperative functional commercial grade products. Among the various bioactive compounds, biosurfactant (BS)/bioemulsifiers (BE) are attracting major interest and attention due to their structural and functional diversity. The versatile properties of surface active molecules find numerous applications in various industries. Marine microorganisms such as Acinetobacter, Arthrobacter, Pseudomonas, Halomonas, Myroides, Corynebacteria, Bacillus, Alteromonas sp. have been studied for production of BS/BE and exopolysaccharides (EPS). Due to the enormity of marine biosphere, most of the marine microbial world remains unexplored. The discovery of potent BS/BE producing marine microorganism would enhance the use of environmental biodegradable surface active molecule and hopefully reduce total dependence or number of new application oriented towards the chemical synthetic surfactant industry. Our present review gives comprehensive information on BS/BE which has been reported to be produced by marine microorganisms and their possible potential future applications. PMID:20172021

  8. Microorganism Utilization for Synthetic Milk Production

    NASA Technical Reports Server (NTRS)

    Birmele, Michele; Morford, Megan; Khodadad, Christina; Spencer, Lashelle; Richards, Jeffrey; Strayer, Richard; Caro, Janicce; Hummerick, Mary; Wheeler, Ray

    2014-01-01

    A desired architecture for long duration spaceflight, such as aboard the International Space Station (ISS) or for future missions to Mars, is to provide a supply of fresh food crops for the astronauts. However, some crops can create a high proportion of inedible plant waste. The main goal of this project was to produce the components of milk (sugar, lipid, protein) from inedible plant waste by utilizing microorganisms (fungi, yeast, bacteria). Of particular interest was utilizing the valuable polysaccharide, cellulose, found in plant waste, to naturally fuel- through microorganism cellular metabolism- the creation of sugar (glucose), lipid (milk fat), and protein (casein) to produce a synthetic edible food product. Environmental conditions such as pH, temperature, carbon source, aeration, and choice microorganisms.

  9. Differences in stability of seed-associated microbial assemblages in response to invasion by phytopathogenic microorganisms

    PubMed Central

    Rezki, Samir; Campion, Claire; Iacomi-Vasilescu, Beatrice; Preveaux, Anne; Toualbia, Youness; Bonneau, Sophie; Briand, Martial; Laurent, Emmanuelle; Hunault, Gilles; Simoneau, Philippe; Jacques, Marie-Agnès

    2016-01-01

    Seeds are involved in the vertical transmission of microorganisms from one plant generation to another and consequently act as reservoirs for the plant microbiota. However, little is known about the structure of seed-associated microbial assemblages and the regulators of assemblage structure. In this work, we have assessed the response of seed-associated microbial assemblages of Raphanus sativus to invading phytopathogenic agents, the bacterial strain Xanthomonas campestris pv. campestris (Xcc) 8004 and the fungal strain Alternaria brassicicola Abra43. According to the indicators of bacterial (16S rRNA gene and gyrB sequences) and fungal (ITS1) diversity employed in this study, seed transmission of the bacterial strain Xcc 8004 did not change the overall composition of resident microbial assemblages. In contrast seed transmission of Abra43 strongly modified the richness and structure of fungal assemblages without affecting bacterial assemblages. The sensitivity of seed-associated fungal assemblage to Abra43 is mostly related to changes in relative abundance of closely related fungal species that belong to the Alternaria genus. Variation in stability of the seed microbiota in response to Xcc and Abra43 invasions could be explained by differences in seed transmission pathways employed by these micro-organisms, which ultimately results in divergence in spatio-temporal colonization of the seed habitat. PMID:27077013

  10. Differences in stability of seed-associated microbial assemblages in response to invasion by phytopathogenic microorganisms.

    PubMed

    Rezki, Samir; Campion, Claire; Iacomi-Vasilescu, Beatrice; Preveaux, Anne; Toualbia, Youness; Bonneau, Sophie; Briand, Martial; Laurent, Emmanuelle; Hunault, Gilles; Simoneau, Philippe; Jacques, Marie-Agnès; Barret, Matthieu

    2016-01-01

    Seeds are involved in the vertical transmission of microorganisms from one plant generation to another and consequently act as reservoirs for the plant microbiota. However, little is known about the structure of seed-associated microbial assemblages and the regulators of assemblage structure. In this work, we have assessed the response of seed-associated microbial assemblages of Raphanus sativus to invading phytopathogenic agents, the bacterial strain Xanthomonas campestris pv. campestris (Xcc) 8004 and the fungal strain Alternaria brassicicola Abra43. According to the indicators of bacterial (16S rRNA gene and gyrB sequences) and fungal (ITS1) diversity employed in this study, seed transmission of the bacterial strain Xcc 8004 did not change the overall composition of resident microbial assemblages. In contrast seed transmission of Abra43 strongly modified the richness and structure of fungal assemblages without affecting bacterial assemblages. The sensitivity of seed-associated fungal assemblage to Abra43 is mostly related to changes in relative abundance of closely related fungal species that belong to the Alternaria genus. Variation in stability of the seed microbiota in response to Xcc and Abra43 invasions could be explained by differences in seed transmission pathways employed by these micro-organisms, which ultimately results in divergence in spatio-temporal colonization of the seed habitat. PMID:27077013

  11. On the Lie subalgebra of Killing-Milne and Killing-Cartan vector fields in Newtonian spacetime

    NASA Astrophysics Data System (ADS)

    Chamel, Nicolas

    2015-12-01

    The Galilean (and more generally Milne) invariance of Newtonian theory allows for Killing vector fields of a general kind, whereby the Lie derivative of a field is not required to vanish but only to be cancellable by some infinitesimal Galilean (respectively Milne) gauge transformation. In this paper, it is shown that both the Killing-Milne vector fields, which preserve the background Newtonian spacetime structure and the Killing-Cartan vector fields, which in addition preserve the gravitational field, form a Lie subalgebra.

  12. Linking the occurrence of cutaneous opportunistic fungal invaders with elemental concentrations in false killer whale (Pseudorca crassidens) skin.

    PubMed

    Mouton, Marnel; Przybylowicz, Wojciech; Mesjasz-Przybylowicz, Jolanta; Postma, Ferdinand; Thornton, Meredith; Archer, Edward; Botha, Alfred

    2015-10-01

    Cetaceans, occupying the top levels in marine food chains, are vulnerable to elevated levels of potentially toxic trace elements, such as aluminium (Al), mercury (Hg) and nickel (Ni). Negative effects associated with these toxic metals include infection by opportunistic microbial invaders. To corroborate the link between the presence of cutaneous fungal invaders and trace element levels, skin samples from 40 stranded false killer whales (FKWs) were analysed using culture techniques and inductively coupled plasma-mass spectroscopy. Twenty-two skin samples yielded 18 clinically relevant fungal species. While evidence for bioaccumulation of Hg in the skin of the FKWs was observed, a strong link was found to exist between the occurrence of opportunistic fungal invaders and higher Al : Se and Al : Zn ratios. This study provides indications that elevated levels of some toxic metals, such as Al, contribute to immunotoxicity rendering FKWs susceptible to colonization by cutaneous opportunistic fungal invaders. PMID:26034019

  13. Functional Properties of Microorganisms in Fermented Foods.

    PubMed

    Tamang, Jyoti P; Shin, Dong-Hwa; Jung, Su-Jin; Chae, Soo-Wan

    2016-01-01

    Fermented foods have unique functional properties imparting some health benefits to consumers due to presence of functional microorganisms, which possess probiotics properties, antimicrobial, antioxidant, peptide production, etc. Health benefits of some global fermented foods are synthesis of nutrients, prevention of cardiovascular disease, prevention of cancer, gastrointestinal disorders, allergic reactions, diabetes, among others. The present paper is aimed to review the information on some functional properties of the microorganisms associated with fermented foods and beverages, and their health-promoting benefits to consumers. PMID:27199913

  14. Screening and Separation of Microorganisms Degrading PCBs.

    PubMed Central

    Bokvajova, A; Burkhard, J; Demnerova, K; Pazlarova, J

    1994-01-01

    We performed an assay to assess the polychlorinated biphenyl (PCB) degradative capability and congener specificity of aerobic microorganisms. Microbial strains were isolated and separated from different types of soils in the Czech Republic, and their PCB-degrading abilities were compared. An industrial mixture of PCB congeners ranging from dichloro- to hexachlorobiphenyl and representing various chlorination patterns was used throughout. The PCB degradative ability of microorganisms was determined by gas chromatography after 7 days of incubation. The degree of degradation was found to depend on the number of chlorine substituents. PMID:9679114

  15. Hydrodynamic Phase Locking of Swimming Microorganisms

    NASA Astrophysics Data System (ADS)

    Elfring, Gwynn J.; Lauga, Eric

    2009-08-01

    Some microorganisms, such as spermatozoa, synchronize their flagella when swimming in close proximity. Using a simplified model (two infinite, parallel, two-dimensional waving sheets), we show that phase locking arises from hydrodynamics forces alone, and has its origin in the front-back asymmetry of the geometry of their flagellar waveform. The time evolution of the phase difference between coswimming cells depends only on the nature of this geometrical asymmetry, and microorganisms can phase lock into conformations which minimize or maximize energy dissipation.

  16. Physiologically anaerobic microorganisms of the deep subsurface

    SciTech Connect

    Stevens, S.E. Jr.; Chung, K.T.

    1991-06-01

    This study seeks to determine numbers, diversity, and morphology of anaerobic microorganisms in 15 samples of subsurface material from the Idaho National Engineering Laboratory, in 18 samples from the Hanford Reservation and in 1 rock sample from the Nevada Test Site; set up long term experiments on the chemical activities of anaerobic microorganisms based on these same samples; work to improve methods for the micro-scale determination of in situ anaerobic microbial activity;and to begin to isolate anaerobes from these samples into axenic culture with identification of the axenic isolates.

  17. Functional Properties of Microorganisms in Fermented Foods

    PubMed Central

    Tamang, Jyoti P.; Shin, Dong-Hwa; Jung, Su-Jin; Chae, Soo-Wan

    2016-01-01

    Fermented foods have unique functional properties imparting some health benefits to consumers due to presence of functional microorganisms, which possess probiotics properties, antimicrobial, antioxidant, peptide production, etc. Health benefits of some global fermented foods are synthesis of nutrients, prevention of cardiovascular disease, prevention of cancer, gastrointestinal disorders, allergic reactions, diabetes, among others. The present paper is aimed to review the information on some functional properties of the microorganisms associated with fermented foods and beverages, and their health-promoting benefits to consumers. PMID:27199913

  18. Inactivation of microorganisms by electrohydraulic shock.

    PubMed

    Gilliland, S E; Speck, M L

    1967-09-01

    The electrohydraulic shock treatment of microorganisms was accomplished by discharging high-voltage electricity (8 to 15 kv) across an electrode gap below the surface of aqueous suspensions of the microorganisms. This treatment was effective in destroying Escherichia coli, Streptococcus faecalis, vegetative cells and spores of Bacillus subtilis, and bacteriophage specific for S. cremoris ML1. The presence of added protein in bacterial suspensions resulted in reduced bactericidal action. Water subjected to electrohydraulic treatment retained a certain amount of toxicity when copper-core electrodes were used to apply the treatment. This was caused by copper liberated from the electrode during electrohydraulic discharge. PMID:4965615

  19. Metabolic activity of microorganisms in evaporites.

    PubMed

    Rothschild, L J; Giver, L J; White, M R; Mancinelli, R L

    1994-06-01

    Crystalline salt is generally considered so hostile to most forms of life that it has been used for centuries as a preservative. Here, we present evidence that prokaryotes inhabiting a natural evaporite crust of halite and gypsum are metabolically active while inside the evaporite for at least 10 months. In situ measurements demonstrated that some of these "endoevaporitic" microorganisms (probably the cyanobacterium Synechococcus Nageli) fixed carbon and nitrogen. Denitrification was not observed. Our results quantified the slow microbial activity that can occur in salt crystals. Implications of this study include the possibility that microorganisms found in ancient evaporite deposits may have been part of an evaporite community. PMID:11539827

  20. Metabolic activity of microorganisms in evaporites

    NASA Technical Reports Server (NTRS)

    Rothschild, L. J.; Giver, L. J.; White, M. R.; Mancinelli, R. L.

    1994-01-01

    Crystalline salt is generally considered so hostile to most forms of life that it has been used for centuries as a preservative. Here, we present evidence that prokaryotes inhabiting a natural evaporite crust of halite and gypsum are metabolically active while inside the evaporite for at least 10 months. In situ measurements demonstrated that some of these "endoevaporitic" microorganisms (probably the cyanobacterium Synechococcus Nageli) fixed carbon and nitrogen. Denitrification was not observed. Our results quantified the slow microbial activity that can occur in salt crystals. Implications of this study include the possibility that microorganisms found in ancient evaporite deposits may have been part of an evaporite community.

  1. Kinetics of killing Listeria monocytogenes by macrophages: rapid killing accompanying phagocytosis

    SciTech Connect

    Davies, W.A.

    1983-08-01

    The kinetics of bactericidal activity of activated macrophages can be precisely described by a mathematical model in which phagocytosis, killing, digestion, and release of degraded bacterial material are considered to occur continuously. To gain a better understanding of these events, I have determined the period of time between first contact of bacteria with macrophages and the onset of killing. Activated rat peritoneal macrophages were incubated for various times up to 15 min with Listeria monocytogenes previously labeled with /sup 3/H-thymidine and the unassociated bacteria removed by two centrifugations through a density interface. Both cell-associated radioactivity and cell-associated viable bacteria, determined as colony forming units after sonication of the cell pellet, increased with time of incubation. However, the specific viability of these bacteria, expressed as the ratio of number of viable bacteria per unit radioactivity declined with time, as an approximate inverse exponential, after a lag period of 2.9 +/- 0.8 min. Evidence is given that other possible causes for this decline in specific viability, other than death of the bacteria, such as preferential ingestion of dead Listeria, clumping of bacteria, variations in autolytic activity, or release of Listericidins are unlikely. I conclude therefore that activated macrophages kill Listeria approximately 3 min after the cell and the bacterium first make contact.

  2. Internalization, phagolysosomal biogenesis and killing of mycobacteria in enucleated epithelial cells.

    PubMed

    de Souza Carvalho, Cristiane; Kasmapour, Bahram; Gronow, Achim; Rohde, Manfred; Rabinovitch, Michel; Gutierrez, Maximiliano Gabriel

    2011-08-01

    Bacterial and parasitic intracellular pathogens or their secreted products have been shown to induce host cell transcriptional responses, which may benefit the host, favour the microorganism or be unrelated to the infection. In most instances, however, it is not known if the host cell nucleus is proximately required for the development of an intracellular infection. This information can be obtained by the infection of artificially enucleated host cells (cytoplasts). This model, although rather extensively used in studies of viral infection, has only been applied to few bacterial pathogens, which do not include Mycobacterium spp. Here, we investigate the internalization, phagosome biogenesis and survival of M. smegmatis in enucleated type II alveolar epithelial cells. Cytoplasts were infected with M. smegmatis, but the percentage of infection was significantly lower than that of nucleated cells. Scanning electron microscopy indicated that in both cells and cytoplasts, bacteria were internalized by a phagocytosis-like mechanism. Interestingly, phagosome fusion with lysosomes and mycobacterial killing were both more efficient in enucleated than in nucleated cells, a finding that may be correlated with the increased number of autophagic vesicles developed in cytoplasts. We provide evidence that although quantitative changes were observed, the full development of the infection, as well as mycobacterial killing did not require the presence of the host cell nucleus. PMID:21658173

  3. Plant litter chemistry and microbial priming regulate the accrual, composition and stability of soil carbon in invaded ecosystems.

    PubMed

    Tamura, Mioko; Tharayil, Nishanth

    2014-07-01

    Soil carbon (C) sequestration, as an ecosystem property, may be strongly influenced by invasive plants capable of depositing disproportionately high quantities of chemically distinct litter that disrupt ecosystem processes. However, a mechanistic understanding of the processes that regulate soil C storage in invaded ecosystems remains surprisingly elusive. Here, we studied the impact of the invasion of two noxious nonnative species, Polygonum cuspidatum, which produces recalcitrant litter, and Pueraria lobata, which produces labile litter, on the quantity, molecular composition, and stability of C in the soils they invade. Compared with an adjacent noninvaded old-field, P. cuspidatum-invaded soils exhibited a 26% increase in C, partially through selective preservation of plant polymers. Despite receiving a 22% higher litter input, P. lobata-invaded Pinus stands exhibited a 28% decrease in soil C and a twofold decrease in plant biomarkers, indicating microbial priming of native soil C. The stability of C exhibited an opposite trend: the proportion of C that was resistant to oxidation was 21% lower in P. cuspidatum-invaded soils and 50% higher in P. lobata-invaded soils. Our results highlight the capacity of invasive plants to feed back to climate change by destabilizing native soil C stocks and indicate that environments that promote the biochemical decomposition of plant litter would enhance the long-term storage of soil C. Further, our study highlights the concurrent influence of dominant plant species on both selective preservation and humification of soil organic matter. PMID:24720813

  4. Design of Targeted B Cell Killing Agents

    PubMed Central

    Ponomarenko, Natalia A.; Stremovskiy, Oleg A.; Kozlov, Leonid V.; Bichucher, Anna M.; Dmitriev, Sergey E.; Smirnov, Ivan V.; Shamborant, Olga G.; Balabashin, Dmitry S.; Sashchenko, Lidia P.; Tonevitsky, Alexander G.; Friboulet, Alain; Gabibov, Alexander G.; Deyev, Sergey M.

    2011-01-01

    B cells play an important role in the pathogenesis of both systemic and organ-specific autoimmune diseases. Autoreactive B cells not only produce autoantibodies, but also are capable to efficiently present specific autoantigens to T cells. Furthermore, B cells can secrete proinflammatory cytokines and amplify the vicious process of self-destruction. B cell-directed therapy is a potentially important approach for treatment of various autoimmune diseases. The depletion of B cells by anti-CD20/19 monoclonal antibody Retuximab® used in autoimmune diseases therapy leads to systemic side effects and should be significantly improved. In this study we designed a repertoire of genetically engineered B cell killers that specifically affected one kind of cells carrying a respective B cell receptor. We constructed immunotoxins (ITs), fused with c-myc epitope as a model targeting sequence, based on barnase, Pseudomonas toxin, Shiga-like toxin E.coli and Fc domain of human antibody IgGγ1. C-MYC hybridoma cell line producing anti-c-myc IgG was chosen as a model for targeted cell depletion. C-myc sequence fused with toxins provided addressed delivery of the toxic agent to the target cells. We demonstrated functional activity of designed ITs in vitro and showed recognition of the fusion molecules by antibodies produced by targeted hybridoma. To study specificity of the proposed B cells killing molecules, we tested a set of created ITs ex vivo, using C-MYC and irrelevant hybridoma cell lines. Pseudomonas-containing IT showed one of the highest cytotoxic effects on the model cells, however, possessed promiscuous specificity. Shiga-like toxin construct demonstrated mild both cytotoxicity and specificity. Barnase and Fc-containing ITs revealed excellent balance between their legibility and toxic properties. Moreover, barnase and Fc molecules fused with c-myc epitope were able to selectively deplete c-myc-specific B cells and decrease production of anti-c-myc antibodies in culture of native splenocytes, suggesting their highest therapeutic potential as targeted B cell killing agents. PMID:21677771

  5. Killing of adherent oral microbes by a non-thermal atmospheric plasma jet.

    PubMed

    Rupf, Stefan; Lehmann, Antje; Hannig, Matthias; Schäfer, Barbara; Schubert, Andreas; Feldmann, Uwe; Schindler, Axel

    2010-02-01

    Atmospheric plasma jets are being intensively studied with respect to potential applications in medicine. The aim of this in vitro study was to test a microwave-powered non-thermal atmospheric plasma jet for its antimicrobial efficacy against adherent oral micro-organisms. Agar plates and dentin slices were inoculated with 6 log(10) c.f.u. cm(-2) of Lactobacillus casei, Streptococcus mutans and Candida albicans, with Escherichia coli as a control. Areas of 1 cm(2) on the agar plates or the complete dentin slices were irradiated with a helium plasma jet for 0.3, 0.6 or 0.9 s mm(-2), respectively. The agar plates were incubated at 37 degrees C, and dentin slices were vortexed in liquid media and suspensions were placed on agar plates. The killing efficacy of the plasma jet was assessed by counting the number of c.f.u. on the irradiated areas of the agar plates, as well as by determination of the number of c.f.u. recovered from dentin slices. A microbe-killing effect was found on the irradiated parts of the agar plates for L. casei, S. mutans, C. albicans and E. coli. The plasma-jet treatment reduced the c.f.u. by 3-4 log(10) intervals on the dentin slices in comparison to recovery rates from untreated controls. The microbe-killing effect was correlated with increasing irradiation times. Thus, non-thermal atmospheric plasma jets could be used for the disinfection of dental surfaces. PMID:19910483

  6. Null conformal Killing-Yano tensors and Birkhoff theorem

    NASA Astrophysics Data System (ADS)

    Ferrando, Joan Josep; Sáez, Juan Antonio

    2016-04-01

    We study the space-times admitting a null conformal Killing-Yano tensor whose divergence defines a Killing vector. We analyze the similarities and differences with the recently studied non null case (Ferrando and Sáez in Gen Relativ Gravit 47:1911, 2015). The results by Barnes concerning the Birkhoff theorem for the case of null orbits are analyzed and generalized.

  7. Male Brown-headed Cowbird Attacks and Kills a Nestling

    USGS Publications Warehouse

    Igl, L.D.

    2003-01-01

    I observed a male Brown-headed Cowbird (Molothrus ater) attack and kill a nestling of an unidentified passerine in a grassland field in Day County, South Dakota, in June 2000. The killing or removal of nestlings by female cowbirds has been reported by others, but this behavior has not been documented previously in male cowbirds.

  8. 7. LOOKING WEST TOWARD SHEEP KILL AREA ON SOUTH END ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. LOOKING WEST TOWARD SHEEP KILL AREA ON SOUTH END OF BUILDING 149; INCLINED CONVEYOR AT LEFT CENTER CARRIED TROLLEYS TO THE AUTOMATIC WASHER/OILER ON THE GALLERY LEVEL - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  9. Microwave irradiation for rapid killing and fixing of plant tissue

    SciTech Connect

    Walsh, G.E.; Bohannon, P.M.; Wessinger-Duvall, P.B.

    1989-01-01

    Irradiation by microwaves allows for rapid killing and fixing of plant tissue, with excellent cellular integrity for histological examination. One or two exposures to microwaves for three seconds in formalin/acetic acid/alcohol gave good preservation of nuclei, chloroplasts, and other plant structures. The microwave method offers a considerable saving of time over traditional methods for killing and fixing plant tissue.

  10. 9 CFR 113.216 - Bovine Rhinotracheitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Virus. 113.216 Section 113.216 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... the Animal and Plant Health Inspection Service. Live Virus Vaccines ... REQUIREMENTS Killed Virus Vaccines § 113.216 Bovine Rhinotracheitis Vaccine, Killed Virus. Infectious...

  11. 9 CFR 113.216 - Bovine Rhinotracheitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Virus. 113.216 Section 113.216 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... the Animal and Plant Health Inspection Service. Live Virus Vaccines ... REQUIREMENTS Killed Virus Vaccines § 113.216 Bovine Rhinotracheitis Vaccine, Killed Virus. Infectious...

  12. 9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Feline Rhinotracheitis Vaccine, Killed Virus. 113.211 Section 113.211 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines §...

  13. 9 CFR 113.205 - Newcastle Disease Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Newcastle Disease Vaccine, Killed Virus. 113.205 Section 113.205 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines §...

  14. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Feline Panleukopenia Vaccine, Killed Virus. 113.203 Section 113.203 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines...

  15. 9 CFR 113.216 - Bovine Rhinotracheitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Virus. 113.216 Section 113.216 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... the Animal and Plant Health Inspection Service. Live Virus Vaccines ... REQUIREMENTS Killed Virus Vaccines § 113.216 Bovine Rhinotracheitis Vaccine, Killed Virus. Infectious...

  16. 9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Virus. 113.211 Section 113.211 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... rhinotracheitis virus furnished or approved by Animal and Plant Health Inspection Service and observed each day... REQUIREMENTS Killed Virus Vaccines § 113.211 Feline Rhinotracheitis Vaccine, Killed Virus....

  17. 9 CFR 113.204 - Mink Enteritis Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Mink Enteritis Vaccine, Killed Virus. 113.204 Section 113.204 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines §...

  18. 9 CFR 113.214 - Parvovirus Vaccine, Killed Virus (Canine).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Parvovirus Vaccine, Killed Virus (Canine). 113.214 Section 113.214 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines...

  19. 9 CFR 113.216 - Bovine Rhinotracheitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Bovine Rhinotracheitis Vaccine, Killed Virus. 113.216 Section 113.216 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines §...

  20. 9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Virus. 113.211 Section 113.211 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... rhinotracheitis virus furnished or approved by Animal and Plant Health Inspection Service and observed each day... REQUIREMENTS Killed Virus Vaccines § 113.211 Feline Rhinotracheitis Vaccine, Killed Virus....

  1. 9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Pseudorabies Vaccine, Killed Virus. 113.213 Section 113.213 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines §...

  2. 9 CFR 113.212 - Bursal Disease Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Bursal Disease Vaccine, Killed Virus. 113.212 Section 113.212 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines §...

  3. 9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Virus. 113.211 Section 113.211 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... rhinotracheitis virus furnished or approved by Animal and Plant Health Inspection Service and observed each day... REQUIREMENTS Killed Virus Vaccines § 113.211 Feline Rhinotracheitis Vaccine, Killed Virus....

  4. 9 CFR 113.216 - Bovine Rhinotracheitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Virus. 113.216 Section 113.216 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... the Animal and Plant Health Inspection Service. Live Virus Vaccines ... REQUIREMENTS Killed Virus Vaccines § 113.216 Bovine Rhinotracheitis Vaccine, Killed Virus. Infectious...

  5. 9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Feline Calicivirus Vaccine, Killed Virus. 113.210 Section 113.210 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines §...

  6. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart...

  7. 9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Virus. 113.211 Section 113.211 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... rhinotracheitis virus furnished or approved by Animal and Plant Health Inspection Service and observed each day... REQUIREMENTS Killed Virus Vaccines § 113.211 Feline Rhinotracheitis Vaccine, Killed Virus....

  8. 9 CFR 113.201 - Canine Distemper Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Canine Distemper Vaccine, Killed Virus. 113.201 Section 113.201 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines §...

  9. The Seal Killing Controversy: What Are the Facts?

    ERIC Educational Resources Information Center

    Scheffer, Victor B.

    1973-01-01

    Discusses the seal controversy using the harp and Alaska fur seals to illustrate the two distinct issues, i.e., conservation (the effect of killing upon the animal population); and two, morality (the effect of killing upon the human spirit). Factual information combines with personal philosophy. (LK)

  10. Control of Influenza and Poliomyelitis with Killed Virus Vaccines

    ERIC Educational Resources Information Center

    Salk, Jonas; Salk, Darrell

    1977-01-01

    Discusses control of poliomyelitis and influenza by live and killed virus vaccines. Considered are the etiological agents, pathogenic mechanisms and epidemiology of each disease. Reviews recent scientific studies of the diseases. Recommends use of killed virus vaccines in controlling both diseases. (CS)

  11. PDE5 Inhibitors Enhance Celecoxib Killing in Multiple Tumor Types

    PubMed Central

    BOOTH, LAURENCE; ROBERTS, JANE L.; CRUICKSHANKS, NICHOLA; TAVALLAI, SEYEDMEHRAD; WEBB, TIMOTHY; SAMUEL, PETER; CONLEY, ADAM; BINION, BRITTANY; YOUNG, HAROLD F.; POKLEPOVIC, ANDREW; SPIEGEL, SARAH; DENT, PAUL

    2015-01-01

    The present studies determined whether clinically relevant phosphodiesterase 5 (PDE5) inhibitors interacted with a clinically relevant NSAID, celecoxib, to kill tumor cells. Celecoxib and PDE5 inhibitors interacted in a greater than additive fashion to kill multiple tumor cell types. Celecoxib and sildenafil killed ex vivo primary human glioma cells as well as their associated activated microglia. Knock down of PDE5 recapitulated the effects of PDE5 inhibitor treatment; the nitric oxide synthase inhibitor L-NAME suppressed drug combination toxicity. The effects of celecoxib were COX2 independent. Over-expression of c-FLIP-s or knock down of CD95/FADD significantly reduced killing by the drug combination. CD95 activation was dependent on nitric oxide and ceramide signaling. CD95 signaling activated the JNK pathway and inhibition of JNK suppressed cell killing. The drug combination inactivated mTOR and increased the levels of autophagy and knock down of Beclin1 or ATG5 strongly suppressed killing by the drug combination. The drug combination caused an ER stress response; knock down of IRE1α/XBP1 enhanced killing whereas knock down of eIF2α/ATF4/CHOP suppressed killing. Sildenafil and celecoxib treatment suppressed the growth of mammary tumors in vivo. Collectively our data demonstrate that clinically achievable concentrations of celecoxib and sildenafil have the potential to be a new therapeutic approach for cancer. PMID:25303541

  12. PDE5 inhibitors enhance celecoxib killing in multiple tumor types.

    PubMed

    Booth, Laurence; Roberts, Jane L; Cruickshanks, Nichola; Tavallai, Seyedmehrad; Webb, Timothy; Samuel, Peter; Conley, Adam; Binion, Brittany; Young, Harold F; Poklepovic, Andrew; Spiegel, Sarah; Dent, Paul

    2015-05-01

    The present studies determined whether clinically relevant phosphodiesterase 5 (PDE5) inhibitors interacted with a clinically relevant NSAID, celecoxib, to kill tumor cells. Celecoxib and PDE5 inhibitors interacted in a greater than additive fashion to kill multiple tumor cell types. Celecoxib and sildenafil killed ex vivo primary human glioma cells as well as their associated activated microglia. Knock down of PDE5 recapitulated the effects of PDE5 inhibitor treatment; the nitric oxide synthase inhibitor L-NAME suppressed drug combination toxicity. The effects of celecoxib were COX2 independent. Over-expression of c-FLIP-s or knock down of CD95/FADD significantly reduced killing by the drug combination. CD95 activation was dependent on nitric oxide and ceramide signaling. CD95 signaling activated the JNK pathway and inhibition of JNK suppressed cell killing. The drug combination inactivated mTOR and increased the levels of autophagy and knock down of Beclin1 or ATG5 strongly suppressed killing by the drug combination. The drug combination caused an ER stress response; knock down of IRE1α/XBP1 enhanced killing whereas knock down of eIF2α/ATF4/CHOP suppressed killing. Sildenafil and celecoxib treatment suppressed the growth of mammary tumors in vivo. Collectively our data demonstrate that clinically achievable concentrations of celecoxib and sildenafil have the potential to be a new therapeutic approach for cancer. PMID:25303541

  13. 9. GENERAL INTERIOR VIEW OF BEEF KILLING FLOOR; LOOKING SOUTHEAST; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. GENERAL INTERIOR VIEW OF BEEF KILLING FLOOR; LOOKING SOUTHEAST; PLATFORMS IN FOREGROUND WERE USED BY SPLITTERS, TRIMMERS AND GOVERNMENT INSPECTORS; SKINNING TABLE RAN ALONG THE WINDOWS NEAR THE CENTER OF THE PHOTO - Rath Packing Company, Beef Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  14. Transcriptome sequencing reveals both neutral and adaptive genome dynamics in a marine invader.

    PubMed

    Tepolt, C K; Palumbi, S R

    2015-08-01

    Species invasions cause significant ecological and economic damage, and genetic information is important to understanding and managing invasive species. In the ocean, many invasive species have high dispersal and gene flow, lowering the discriminatory power of traditional genetic approaches. High-throughput sequencing holds tremendous promise for increasing resolution and illuminating the relative contributions of selection and drift in marine invasion, but has not yet been used to compare the diversity and dynamics of a high-dispersal invader in its native and invaded ranges. We test a transcriptome-based approach in the European green crab (Carcinus maenas), a widespread invasive species with high gene flow and a well-known invasion history, in two native and five invasive populations. A panel of 10 809 transcriptome-derived nuclear SNPs identified significant population structure among highly bottlenecked invasive populations that were previously undifferentiated with traditional markers. Comparing the full data set and a subset of 9246 putatively neutral SNPs strongly suggested that non-neutral processes are the primary driver of population structure within the species' native range, while neutral processes appear to dominate in the invaded range. Non-neutral native range structure coincides with significant differences in intraspecific thermal tolerance, suggesting temperature as a potential selective agent. These results underline the importance of adaptation in shaping intraspecific differences even in high geneflow marine invasive species. They also demonstrate that high-throughput approaches have broad utility in determining neutral structure in recent invasions of such species. Together, neutral and non-neutral data derived from high-throughput approaches may increase the understanding of invasion dynamics in high-dispersal species. PMID:26118396

  15. Plasmodium falciparum evades mosquito immunity by disrupting JNK-mediated apoptosis of invaded midgut cells

    PubMed Central

    Ramphul, Urvashi N.; Garver, Lindsey S.; Molina-Cruz, Alvaro; Canepa, Gaspar E.; Barillas-Mury, Carolina

    2015-01-01

    The malaria parasite, Plasmodium, must survive and develop in the mosquito vector to be successfully transmitted to a new host. The Plasmodium falciparum Pfs47 gene is critical for malaria transmission. Parasites that express Pfs47 (NF54 WT) evade mosquito immunity and survive, whereas Pfs47 knockouts (KO) are efficiently eliminated by the complement-like system. Two alternative approaches were used to investigate the mechanism of action of Pfs47 on immune evasion. First, we examined whether Pfs47 affected signal transduction pathways mediating mosquito immune responses, and show that the Jun-N-terminal kinase (JNK) pathway is a key mediator of Anopheles gambiae antiplasmodial responses to P. falciparum infection and that Pfs47 disrupts JNK signaling. Second, we used microarrays to compare the global transcriptional responses of A. gambiae midguts to infection with WT and KO parasites. The presence of Pfs47 results in broad and profound changes in gene expression in response to infection that are already evident 12 h postfeeding, but become most prominent at 26 h postfeeding, the time when ookinetes invade the mosquito midgut. Silencing of 15 differentially expressed candidate genes identified caspase-S2 as a key effector of Plasmodium elimination in parasites lacking Pfs47. We provide experimental evidence that JNK pathway regulates activation of caspases in Plasmodium-invaded midgut cells, and that caspase activation is required to trigger midgut epithelial nitration. Pfs47 alters the cell death pathway of invaded midgut cells by disrupting JNK signaling and prevents the activation of several caspases, resulting in an ineffective nitration response that makes the parasite undetectable by the mosquito complement-like system. PMID:25552553

  16. Metagenomics: Application of Genomics to Uncultured Microorganisms

    PubMed Central

    Handelsman, Jo

    2004-01-01

    Metagenomics (also referred to as environmental and community genomics) is the genomic analysis of microorganisms by direct extraction and cloning of DNA from an assemblage of microorganisms. The development of metagenomics stemmed from the ineluctable evidence that as-yet-uncultured microorganisms represent the vast majority of organisms in most environments on earth. This evidence was derived from analyses of 16S rRNA gene sequences amplified directly from the environment, an approach that avoided the bias imposed by culturing and led to the discovery of vast new lineages of microbial life. Although the portrait of the microbial world was revolutionized by analysis of 16S rRNA genes, such studies yielded only a phylogenetic description of community membership, providing little insight into the genetics, physiology, and biochemistry of the members. Metagenomics provides a second tier of technical innovation that facilitates study of the physiology and ecology of environmental microorganisms. Novel genes and gene products discovered through metagenomics include the first bacteriorhodopsin of bacterial origin; novel small molecules with antimicrobial activity; and new members of families of known proteins, such as an Na+(Li+)/H+ antiporter, RecA, DNA polymerase, and antibiotic resistance determinants. Reassembly of multiple genomes has provided insight into energy and nutrient cycling within the community, genome structure, gene function, population genetics and microheterogeneity, and lateral gene transfer among members of an uncultured community. The application of metagenomic sequence information will facilitate the design of better culturing strategies to link genomic analysis with pure culture studies. PMID:15590779

  17. Radiation sensitivity of hyperthermal composting microorganisms

    NASA Astrophysics Data System (ADS)

    Choi, Jong-Il; Yoon, Min-Chul; Kim, Jae-Hun; Yamashita, Masamichi; Kim, Geun Joong; Lee, Ju-Woon

    In the space station and vehicles designed for long human mission, high-temperature compost is a promising technology for decomposing organic waste and producing the fertilizers. In space, the microorganisms could have the changed biological activities or even be mutated by ionizing irradiation. Therefore, in this study, the effect of gamma irradiation on the sensitivity of bacteria in hyperthermal composting was investigated. The sequence analysis of the amplified 16s rDNA genes and amoA gene were used for the identification of composting microorganisms. Viability of microorganisms in compost soil after gamma irradiation was directly visualized with LIVE/DEAD Baclight viability kit. The dominant bacterial genera are Weissella cibaria and Leuconostoc sp. and fungus genera are Metschnikowia bicuspidate and Pichia guilliermondii, respectively. By the gamma irradiation up to the dose of 1 kGy, the microbial population was not changed. Also, the enzyme activities of amylase and cellulose were sustained by the gamma irradiation. These results show that these hyperthermia microorganisms might have the high resistance to gamma radiation and could be used for agriculture in the Space Station.

  18. [DIFFERENTIAL SENSITIVITY OF MICROORGANISMS TO POLYHEXAMETHYLENEGUANIDINE].

    PubMed

    Lysytsya, A V; Mandygra, Y M; Bojko, O P; Romanishyna, O O; Mandygra, M S

    2015-01-01

    Factors identified that affect the sensitivity of microorganisms to polyhexamethyleneguanidine (PHMG). Salts of PHMG chloride, valerate, maleate, succinate was to use. Test strains of Esherichia coli, Staphylococcus aureus, Bacillus cereus, Leptospira interrogans, Paenibacillus larvae, Mycobacterium bovis, M. avium, M. fortuitum, Aspergillus niger and some strains of viruses are taken as objects of research. We have determined that the cytoplasm membrane phospholipids is main "target" for the polycation molecules of PHMG. A differential sensitivity of the microorganisms to this drug is primarily determined by relative amount of lipids in membrane and their accessibility. Such trends exist: increase the relative contents of anionic lipids and more negative surface electric potential of membrane, and reduction of the sizes fat acid remainder of lipids bring to increase of microorganism sensitivity. Types of anion salt PHMG just have a certain value. Biocide activity of PHMG chloride is more, than its salts with organic acid. Feasibility of combining PHMG with other biocides in the multicomponent disinfectants studied and analyzed. This combination does not lead to a significant increase in the sensitivity of microorganisms tested in most cases. Most species of pathogenic bacteria can be quickly neutralized by aqueous solutions of PHMG in less than 1% concentrations. PMID:26638480

  19. Engineered microorganisms having resistance to ionic liquids

    DOEpatents

    Ruegg, Thomas Lawrence; Thelen, Michael P.

    2016-03-22

    The present invention provides for a method of genetically modifying microorganisms to enhance resistance to ionic liquids, host cells genetically modified in accordance with the methods, and methods of using the host cells in a reaction comprising biomass that has been pretreated with ionic liquids.

  20. Measuring micro-organism gas production

    NASA Technical Reports Server (NTRS)

    Wilkins, J. R.; Pearson, A. O.; Mills, S. M.

    1973-01-01

    Transducer, which senses pressure buildup, is easy to assemble and use, and rate of gas produced can be measured automatically and accurately. Method can be used in research, in clinical laboratories, and for environmental pollution studies because of its ability to detect and quantify rapidly the number of gas-producing microorganisms in water, beverages, and clinical samples.

  1. Biomechanics of Aquatic Micro-Organisms

    NASA Astrophysics Data System (ADS)

    Pedley, T. J.

    Aquatic micro-organisms play a major role in ocean ecology, the global carbon cycle and bioreactor engineering. The complex foodweb of an oceanic ecosystem may be modelled in terms of a few species of different types whose population densities obey coupled differential equations. However the functions and constants that appear in those equations depend in a complex way on the details of the dynamics of individual organisms and how they interact in larger scale phenomena. This talk will survey some of the following topics: (1) the fluid dynamics of micro-organism swimming, (2) the effect on nutrient uptake of an organism’s swimming motions, (3) chemotaxis in bacteria, (4) capture rate of phytoplankton by zooplankton when they all swim in a turbulent environment, (5) pattern-formation (e.g. bioconvection) in suspensions of upswimming micro-organisms (algae and bacteria), (6) the hydrodynamic interactions between swimming model micro-organisms and (7) their effect on the rheology and transport properties of the suspension as a whole. The long-term goal is to formulate a continuum model for concentrated suspensions of swimmers; this is not yet realised and may be impossible!

  2. PESTICIDE METABOLISM IN PLANTS AND MICROORGANISMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding pesticide metabolism in plants and microorganisms is necessary for pesticide development, safe and efficient use, as well as for developing pesticide bioremediation strategies for contaminated soil and water. Pesticide biotransformation may occur via multi-step processes known as meta...

  3. Human recombinant lysosomal enzymes produced in microorganisms.

    PubMed

    Espejo-Mojica, Ángela J; Alméciga-Díaz, Carlos J; Rodríguez, Alexander; Mosquera, Ángela; Díaz, Dennis; Beltrán, Laura; Díaz, Sergio; Pimentel, Natalia; Moreno, Jefferson; Sánchez, Jhonnathan; Sánchez, Oscar F; Córdoba, Henry; Poutou-Piñales, Raúl A; Barrera, Luis A

    2015-01-01

    Lysosomal storage diseases (LSDs) are caused by accumulation of partially degraded substrates within the lysosome, as a result of a function loss of a lysosomal protein. Recombinant lysosomal proteins are usually produced in mammalian cells, based on their capacity to carry out post-translational modifications similar to those observed in human native proteins. However, during the last years, a growing number of studies have shown the possibility to produce active forms of lysosomal proteins in other expression systems, such as plants and microorganisms. In this paper, we review the production and characterization of human lysosomal proteins, deficient in several LSDs, which have been produced in microorganisms. For this purpose, Escherichia coli, Saccharomyces cerevisiae, Pichia pastoris, Yarrowia lipolytica, and Ogataea minuta have been used as expression systems. The recombinant lysosomal proteins expressed in these hosts have shown similar substrate specificities, and temperature and pH stability profiles to those produced in mammalian cells. In addition, pre-clinical results have shown that recombinant lysosomal enzymes produced in microorganisms can be taken-up by cells and reduce the substrate accumulated within the lysosome. Recently, metabolic engineering in yeasts has allowed the production of lysosomal enzymes with tailored N-glycosylations, while progresses in E. coli N-glycosylations offer a potential platform to improve the production of these recombinant lysosomal enzymes. In summary, microorganisms represent convenient platform for the production of recombinant lysosomal proteins for biochemical and physicochemical characterization, as well as for the development of ERT for LSD. PMID:26071627

  4. Microorganism lipid droplets and biofuel development.

    PubMed

    Liu, Yingmei; Zhang, Congyan; Shen, Xipeng; Zhang, Xuelin; Cichello, Simon; Guan, Hongbin; Liu, Pingsheng

    2013-12-01

    Lipid droplet (LD) is a cellular organelle that stores neutral lipids as a source of energy and carbon. However, recent research has emerged that the organelle is involved in lipid synthesis, transportation, and metabolism, as well as mediating cellular protein storage and degradation. With the exception of multi-cellular organisms, some unicellular microorganisms have been observed to contain LDs. The organelle has been isolated and characterized from numerous organisms. Triacylglycerol (TAG) accumulation in LDs can be in excess of 50% of the dry weight in some microorganisms, and a maximum of 87% in some instances. These microorganisms include eukaryotes such as yeast and green algae as well as prokaryotes such as bacteria. Some organisms obtain carbon from CO2 via photosynthesis, while the majority utilizes carbon from various types of biomass. Therefore, high TAG content generated by utilizing waste or cheap biomass, coupled with an efficient conversion rate, present these organisms as bio-tech 'factories' to produce biodiesel. This review summarizes LD research in these organisms and provides useful information for further LD biological research and microorganism biodiesel development. PMID:24355300

  5. [DATABASE FOR DEPOSITARY DEPARTMENT OF MICROORGANISMS].

    PubMed

    Brovarnyk, V; Golovach, T M

    2015-01-01

    The database on microorganism culture depositary is designed with using MS Access 2010. Three major modules, namely general description, administration, storage, compound database kernel. Description of information in these modules is given. Web page of the depositary is developed on the database. PMID:26638488

  6. 40 CFR 725.85 - Microorganism identity.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access... submitter believes that public disclosure prior to commencement of manufacture or import for general... claim. (i) A person who believes that public disclosure of the fact that anyone manufactures or...

  7. Microorganism lipid droplets and biofuel development

    PubMed Central

    Liu, Yingmei; Zhang, Congyan; Shen, Xipeng; Zhang, Xuelin; Cichello, Simon; Guan, Hongbin; Liu, Pingsheng

    2013-01-01

    Lipid droplet (LD) is a cellular organelle that stores neutral lipids as a source of energy and carbon. However, recent research has emerged that the organelle is involved in lipid synthesis, transportation, and metabolism, as well as mediating cellular protein storage and degradation. With the exception of multi-cellular organisms, some unicellular microorganisms have been observed to contain LDs. The organelle has been isolated and characterized from numerous organisms. Triacylglycerol (TAG) accumulation in LDs can be in excess of 50% of the dry weight in some microorganisms, and a maximum of 87% in some instances. These microorganisms include eukaryotes such as yeast and green algae as well as prokaryotes such as bacteria. Some organisms obtain carbon from CO2 via photosynthesis, while the majority utilizes carbon from various types of biomass. Therefore, high TAG content generated by utilizing waste or cheap biomass, coupled with an efficient conversion rate, present these organisms as bio-tech ‘factories’ to produce biodiesel. This review summarizes LD research in these organisms and provides useful information for further LD biological research and microorganism biodiesel development. [BMB Reports 2013; 46(12): 575-581] PMID:24355300

  8. Mechanisms of Dendritic Cell Lysosomal Killing of Cryptococcus

    NASA Astrophysics Data System (ADS)

    Hole, Camaron R.; Bui, Hoang; Wormley, Floyd L.; Wozniak, Karen L.

    2012-10-01

    Cryptococcus neoformans is an opportunistic pulmonary fungal pathogen that disseminates to the CNS causing fatal meningitis in immunocompromised patients. Dendritic cells (DCs) phagocytose C. neoformans following inhalation. Following uptake, cryptococci translocate to the DC lysosomal compartment and are killed by oxidative and non-oxidative mechanisms. DC lysosomal extracts kill cryptococci in vitro; however, the means of antifungal activity remain unknown. Our studies determined non-oxidative antifungal activity by DC lysosomal extract. We examined DC lysosomal killing of cryptococcal strains, anti-fungal activity of purified lysosomal enzymes, and mechanisms of killing against C. neoformans. Results confirmed DC lysosome fungicidal activity against all cryptococcal serotypes. Purified lysosomal enzymes, specifically cathepsin B, inhibited cryptococcal growth. Interestingly, cathepsin B combined with its enzymatic inhibitors led to enhanced cryptococcal killing. Electron microscopy revealed structural changes and ruptured cryptococcal cell walls following treatment. Finally, additional studies demonstrated that osmotic lysis was responsible for cryptococcal death.

  9. Glochidioboside Kills Pathogenic Bacteria by Membrane Perturbation.

    PubMed

    Lee, Heejeong; Woo, Eun-Rhan; Lee, Dong Gun

    2015-07-01

    The aim of this study was to evaluate the antibacterial effects of glochidioboside and determine its mechanism of action. Glochidioboside has been reported to be isolated from some plants but the underlying biological properties have remained largely obscure until now. To identify the antibacterial activity of all biological properties, pathogenic bacteria susceptibility test was performed, and the result shows that the compound displays remarkable antibacterial activity against antibiotic-resistant bacteria not to mention general pathogen. To demonstrate membrane disruption and depolarization, SYTOX green and bis-(1,3-dibutylbarbituric acid) trimethine oxonol were used with Escherichia coli O157, and indicated that glochidioboside affected cytoplasmic membranes by permeabilization and depolarization, respectively. Calcein efflux was evident in a membrane model that encapsulated fluorescent dye, and supported the hypothesis of a membrane-active mechanism. To confirm the release of intracellular matrix owing to membrane damage, the movements of potassium ion were observed; the results indicated that the cells treated with glochidioboside leaked potassium ion, thus the damage induced by the compounds lead to leaking intracellular components. We propose that glochidioboside kills pathogenic bacteria via perturbation of integrity of the membrane. PMID:25820208

  10. Boromycin Kills Mycobacterial Persisters without Detectable Resistance

    PubMed Central

    Moreira, Wilfried; Aziz, Dinah B.; Dick, Thomas

    2016-01-01

    Boromycin is a boron-containing polyether macrolide antibiotic isolated from Streptomyces antibioticus. It was shown to be active against Gram positive bacteria and to act as an ionophore for potassium ions. The antibiotic is ineffective against Gram negative bacteria where the outer membrane appears to block access of the molecule to the cytoplasmic membrane. Here we asked whether boromycin is active against Mycobacterium tuberculosis which, similar to Gram negative bacteria, possesses an outer membrane. The results show that boromycin is a potent inhibitor of mycobacterial growth (MIC50 = 80 nM) with strong bactericidal activity against growing and non-growing drug tolerant persister bacilli. Exposure to boromycin resulted in a rapid loss of membrane potential, reduction of the intracellular ATP level and leakage of cytoplasmic protein. Consistent with boromycin acting as a potassium ionophore, addition of KCl to the medium blocked its antimycobacterial activity. In contrast to the potent antimycobacterial activities of the polyether macrolide, its cytotoxicity and haemolytic activity were low (CC50 = 30 μM, HC50 = 40 μM) with a selectivity index of more than 300. Spontaneous resistant mutants could not be isolated suggesting a mutation frequency of less than 10-9/CFU. Taken together, the results suggests that targeting mycobacterial transmembrane ion gradients may be an attractive chemotherapeutic intervention level to kill otherwise drug tolerant persister bacilli, and to slow down the development of genetic antibiotic resistance. PMID:26941723

  11. Opportunities for renewable bioenergy using microorganisms.

    PubMed

    Rittmann, Bruce E

    2008-06-01

    Global warming can be slowed, and perhaps reversed, only when society replaces fossil fuels with renewable, carbon-neutral alternatives. The best option is bioenergy: the sun's energy is captured in biomass and converted to energy forms useful to modern society. To make a dent in global warming, bioenergy must be generated at a very high rate, since the world today uses approximately 10 TW of fossil-fuel energy. And, it must do so without inflicting serious damage on the environment or disrupting our food supply. While most bioenergy options fail on both counts, several microorganism-based options have the potential to produce large amounts of renewable energy without disruptions. In one approach, microbial communities convert the energy value of various biomass residuals to socially useful energy. Biomass residuals come from agricultural, animal, and a variety of industrial operations, as well as from human wastes. Microorganisms can convert almost all of the energy in these wastes to methane, hydrogen, and electricity. In a second approach, photosynthetic microorganisms convert sunlight into biodiesel. Certain algae (eukaryotes) or cyanobacteria (prokaryotes) have high lipid contents. Under proper conditions, these photosynthetic microorganisms can produce lipids for biodiesel with yields per unit area 100 times or more than possible with any plant system. In addition, the non-lipid biomass can be converted to methane, hydrogen, or electricity. Photosynthetic microorganisms do not require arable land, an advantage because our arable land must be used to produce food. Algae or cyanobacteria may be the best option to produce bioenergy at rates high enough to replace a substantial fraction of our society's use of fossil fuels. PMID:18431744

  12. [Time point and methods for emergency killing in cattle].

    PubMed

    Khol, J L; Schafbauer, T; Wittek, T

    2016-02-16

    Emergency killing is defined as the killing of injured or ill animals to avoid excessive pain or harm. Decision-making for emergency killing or a prolonged therapy can be difficult and has to be based on the case history and results of the clinical examination contributing to the prognosis, particularly in downer cows. Evaluation of enzyme activities and total bilirubin can be used as additional factors pointing to a guarded prognosis; however, none of these parameters provides a clear cut-off value indicating a poor prognosis and mandatory emergency killing. Euthanasia by intravenous drug application is seen as the least stressful method of killing and should therefore always be the first method of choice for emergency killing in cattle. Drugs containing pentobarbital as well as a combination of three different drugs (T61®-Injektionslösung, MSD Animal Health) are available for euthanasia in cattle. All drugs must be administered by a veterinarian. Before application of pentobarbital, an animal should be deeply sedated. The administration of T61® requires anaesthesia of the animal and it is not licensed for use in pregnant animals. Alternative methods for emeragency killing, including captive bolt stunning and the use of firearms, although not regularly performed by veterinarians, should be assessed concerning their correct application and performance. When captive bolt stunning or emergency killing using firearms is performed, the correct position of the device is crucial as well as a quick exsanguination or the application of a pithing rod for the actual killing of the animal after captive bolt stunning. In addition to medical considerations, economic and personal factors contribute to the decision about emergency killing in cattle. Therefore, veterinarians should aim to evaluate each case thoroughly based on personal knowledge and experience, case history, clinical findings and laboratory parameters to avoid prolonged suffering of the animal. PMID:26830543

  13. On pseudo-Riemannian manifolds with many Killing spinors

    SciTech Connect

    Alekseevsky, D. V.; Cortes, V.

    2009-02-02

    Let M be a pseudo-Riemannian spin manifold of dimension n and signature s and denote by N the rank of the real spinor bundle. We prove that M is locally homogeneous if it admits more than (3/4)N independent Killing spinors with the same Killing number, unless n {identical_to} 1(mod 4) and s {identical_to} 3(mod 4). We also prove that M is locally homogeneous if it admits k{sub +} independent Killing spinors with Killing number {lambda} and k{sub -} independent Killing spinors with Killing number -{lambda} such that k{sub +}+k{sub -}>(3/2)N, unless n {identical_to} s {identical_to} 3(mod 4). Similarly, a pseudo-Riemannian manifold with more than (3/4)N independent conformal Killing spinors is conformally locally homogeneous. For (positive or negative) definite metrics, the bounds (3/4)N and (3/2)N in the above results can be relaxed to (1/2)N and N, respectively. Furthermore, we prove that a pseudo-Riemannnian spin manifold with more than (3/4)N parallel spinors is flat and that (1/4)N parallel spinors suffice if the metric is definite. Similarly, a Riemannnian spin manifold with more than (3/8)N Killing spinors with the Killing number {lambda}(set-membership sign)R has constant curvature 4{lambda}{sup 2}. For Lorentzian or negative definite metrics the same is true with the bound (1/2)N. Finally, we give a classification of (not necessarily complete) Riemannian manifolds admitting Killing spinors, which provides an inductive construction of such manifolds.

  14. Managing Threat, Cost, and Incentive to Kill: The Short- and Long-Term Effects of Intervention in Mass Killings

    ERIC Educational Resources Information Center

    Kathman, Jacob D.; Wood, Reed M.

    2011-01-01

    How do third-party interventions affect the severity of mass killings? The authors theorize that episodes of mass killing are the consequence of two factors: (1) the threat perceptions of the perpetrators and (2) the cost of implementing genocidal policies relative to other alternatives. To reduce genocidal hostilities, interveners must address…

  15. Psychological traits underlying different killing methods among Malaysian male murderers.

    PubMed

    Kamaluddin, Mohammad Rahim; Shariff, Nadiah Syariani; Nurfarliza, Siti; Othman, Azizah; Ismail, Khaidzir H; Mat Saat, Geshina Ayu

    2014-04-01

    Murder is the most notorious crime that violates religious, social and cultural norms. Examining the types and number of different killing methods that used are pivotal in a murder case. However, the psychological traits underlying specific and multiple killing methods are still understudied. The present study attempts to fill this gap in knowledge by identifying the underlying psychological traits of different killing methods among Malaysian murderers. The study adapted an observational cross-sectional methodology using a guided self-administered questionnaire for data collection. The sampling frame consisted of 71 Malaysian male murderers from 11 Malaysian prisons who were selected using purposive sampling method. The participants were also asked to provide the types and number of different killing methods used to kill their respective victims. An independent sample t-test was performed to establish the mean score difference of psychological traits between the murderers who used single and multiple types of killing methods. Kruskal-Wallis tests were carried out to ascertain the psychological trait differences between specific types of killing methods. The results suggest that specific psychological traits underlie the type and number of different killing methods used during murder. The majority (88.7%) of murderers used a single method of killing. Multiple methods of killing was evident in 'premeditated' murder compared to 'passion' murder, and revenge was a common motive. Examples of multiple methods are combinations of stabbing and strangulation or slashing and physical force. An exception was premeditated murder committed with shooting, when it was usually a single method, attributed to the high lethality of firearms. Shooting was also notable when the motive was financial gain or related to drug dealing. Murderers who used multiple killing methods were more aggressive and sadistic than those who used a single killing method. Those who used multiple methods or slashing also displayed a higher level of minimisation traits. Despite its limitations, this study has provided some light on the underlying psychological traits of different killing methods which is useful in the field of criminology. PMID:24763234

  16. When CO2 kills: effects of magmatic CO2 flux on belowground biota at Mammoth Mountain, CA

    NASA Astrophysics Data System (ADS)

    McFarland, J.; Waldrop, M. P.; Mangan, M.

    2011-12-01

    The biomass, composition, and activity of the soil microbial community is tightly linked to the composition of the aboveground plant community. Microorganisms in aerobic surface soils, both free-living and plant-associated are largely structured by the availability of growth limiting carbon (C) substrates derived from plant inputs. When C availability declines following a catastrophic event such as the death of large swaths of trees, the number and composition of microorganisms in soil would be expected to decline and/or shift to unique microorganisms that have better survival strategies under starvation conditions. High concentrations of volcanic cold CO2 emanating from Mammoth Mountain near Horseshoe Lake on the southwestern edge of Long Valley Caldera, CA has resulted in a large kill zone of tree species, and associated soil microbial species. In July 2010, we assessed belowground microbial community structure in response to disturbance of the plant community along a gradient of soil CO2 concentrations grading from <0.6% (ambient forest) to >80% (no plant life). We employed a microbial community fingerprinting technique (automated ribosomal intergenic spacer analysis) to determine changes in overall community composition for three broad functional groups: fungi, bacteria, and archaea. To evaluate changes in ectomycorrhizal fungal associates along the CO2 gradient, we harvested root tips from lodgepole pine seedlings collected in unaffected forest as well as at the leading edge of colonization into the kill zone. We also measured soil C fractions (dissolved organic C, microbial biomass C, and non-extractable C) at 10 and 30 cm depth, as well as NH4+. Not surprisingly, our results indicate a precipitous decline in soil C, and microbial C with increasing soil CO2; phospholipid fatty acid analysis in conjunction with community fingerprinting indicate both a loss of fungal diversity as well as a dramatic decrease in biomass as one proceeds further into the kill zone. This observation was concomitant with a relative increase in bacterial and archaeal contributions to microbial community structure. Root tip analyses among lodgepole seedlings recolonizing the kill zone area demonstrated a significant reduction in the overall diversity of fungal symbionts, as well as a distinct shift in fungal assemblages. In particular, within elevated CO2 areas, we observed a high infection level for the ascomycetous fungi, Wilcoxina spp., which appear particularly well-adapted for colonization in disturbed environments. It remains unclear whether dominance by ascomycetes among seedlings in elevated CO2 areas represents a coordinated shift orchestrated by the plant in response to physiological stress, or whether these fungi are simply more opportunistic than their basdiomycetous counterparts. Our results demonstrate the impact of large-scale disturbances on plant-microbial interactions and belowground processes in previously forested ecosystems.

  17. Recombinant microorganisms for increased production of organic acids

    DOEpatents

    Yi, Jian; Kleff, Susanne; Guettler, Michael V

    2013-04-30

    Disclosed are recombinant microorganisms for producing organic acids. The recombinant microorganisms express a polypeptide that has the enzymatic activity of an enzyme that is utilized in the pentose phosphate cycle. The recombinant microorganism may include recombinant Actinobacillus succinogenes that has been transformed to express a Zwischenferment (Zwf) gene. The recombinant microorganisms may be useful in fermentation processes for producing organic acids such as succinic acid and lactic acid. Also disclosed are novel plasmids that are useful for transforming microorganisms to produce recombinant microorganisms that express enzymes such as Zwf.

  18. Recombinant microorganisms for increased production of organic acids

    DOEpatents

    Yi, Jian; Kleff, Susanne; Guettler, Michael V.

    2012-02-21

    Disclosed are recombinant microorganisms for producing organic acids. The recombinant microorganisms express a polypeptide that has the enzymatic activity of an enzyme that is utilized in the pentose phosphate cycle. The recombinant microorganism may include recombinant Actinobacillus succinogenes that has been transformed to express a Zwischenferment (Zwf) gene. The recombinant microorganisms may be useful in fermentation processes for producing organic acids such as succinic acid and lactic acid. Also disclosed are novel plasmids that are useful for transforming microorganisms to produce recombinant microorganisms that express enzymes such as Zwf.

  19. A Successful Crayfish Invader Is Capable of Facultative Parthenogenesis: A Novel Reproductive Mode in Decapod Crustaceans

    PubMed Central

    Buřič, Miloš; Hulák, Martin; Kouba, Antonín

    2011-01-01

    Biological invasions are impacting biota worldwide, and explaining why some taxa tend to become invasive is of major scientific interest. North American crayfish species, particularly of the family Cambaridae, are prominent invaders in freshwaters, defying the “tens rule” which states that only a minority of species introduced to new regions become established, and only a minority of those become invasive and pests. So far, success of cambarid invaders has largely been attributed to rapid maturation, high reproductive output, aggressiveness, and tolerance to pollution. We provide experimental evidence that females of one cambarid species particularly widespread in Europe, the spiny-cheek crayfish Orconectes limosus, are capable of facultative parthenogenesis. Such reproductive mode has never before been recognized in decapods, the most diverse crustacean order. As shown by analysis of seven microsatellite loci, crayfish females kept physically separated from males produced genetically homogeneous offspring identical with maternal individuals; this suggests they reproduced by apomixis, unlike those females which mated with males and had a diverse offspring. Further research is needed to clarify what environmental conditions are necessary for a switch to parthenogenesis in O. limosus, and what role it plays in natural crayfish populations. However, if such reproductive plasticity is present in other cambarid crayfish species, it may contribute to the overwhelming invasive success of this group. PMID:21655282

  20. Curvilinear effects of invasive plants on plant diversity: plant community invaded by Sphagneticola trilobata.

    PubMed

    Qi, Shan-Shan; Dai, Zhi-Cong; Zhai, De-Li; Chen, Si-Chong; Si, Chun-Can; Huang, Ping; Wang, Rui-Ping; Zhong, Qiong-Xin; Du, Dao-Lin

    2014-01-01

    The effects of invasive plants on the species diversity of plant communities are controversial, showing either a positive or negative linear relationship. Based on community data collected from forty 5 m×5 m plots invaded by Sphagneticola trilobata in eight cities across Hainan Island, China, we found S. trilobata decreased plant community diversity once its cover was beyond 10%. We demonstrated that the effects of invasive/native plants on the plant diversity of communities invaded by S. trilobata were curvilinear. These effects, which showed peaks under different degrees of vegetation cover, appeared not only for S. trilobata and all invasive plants, but also for all native plants. Invasive plants primarily had negative effects on plant diversity when they became abundant at a much lower cover level (less than 35%), compared with the native plants (over 60%). Thus, it is necessary to distinguish a range for assessing the effects of plants, especially invasive plants. Our results also confirmed that the invasion intensity of invasive alien plants increased with the intensity of local economic development. We highlight and further discuss the critical importance of curvilinear effects of biological invasion to provide ideas regarding the conservation of local biodiversity and the management of invasive plants. PMID:25426856

  1. Space invaders - A netnographic study of how artefacts in nursing home environments exercise disciplining structures.

    PubMed

    Salzmann-Erikson, Martin

    2016-06-01

    This study aims to present culturally situated artefacts as depicted in nursing home environments and to analyse the underlying understandings of disciplining structures that are manifested in these kinds of places. Our personal geographies are often taken for granted, but when moving to a nursing home, geographies are glaringly rearranged. The study design is archival and cross-sectional observational, and the data are comprised of 38 photographs and 13 videos showing environments from nursing homes. The analysis was inspired by the methodological steps in Roper's and Shapira's description of conducting ethnography. The results are presented in four categories: (i) public areas, (ii) orderliness, (iii) staff's places and (iv) devices. The rearrangement of geography implies a degrading of agency and loss of authority over one's place. The places should be understood in their relation to the agents and their temporarily claims upon them. The material and immaterial artefacts, that is the items, people and behaviours, transform the nursing staff into 'space invaders'. Future inquiries may take into consideration the ways that space invasion in participative space intersect and construct the identities of the agents it invades upon. PMID:26676798

  2. Invaders do not require high resource levels to maintain physiological advantages in a temperate deciduous forest.

    PubMed

    Heberling, J Mason; Fridley, Jason D

    2016-04-01

    Non-native, invasive plants are commonly typified by trait strategies associated with high resource demands and plant invasions are often thought to be dependent upon site resource availability or disturbance. However, the invasion of shade-tolerant woody species into deciduous forests of the Eastern United States seems to contradict such generalization, as growth in this ecosystem is strongly constrained by light and, secondarily, nutrient stress. In a factorial manipulation of light and soil nitrogen availability, we established an experimental resource gradient in a secondary deciduous forest to test whether three common, woody, invasive species displayed increased metabolic performance and biomass production compared to six co-occurring woody native species, and whether these predicted differences depend upon resource supply. Using hierarchical Bayesian models of photosynthesis that included leaf trait effects, we found that invasive species exhibited functional strategies associated with higher rates of carbon gain. Further, invader metabolic and growth-related attributes were more responsive to increasing light availability than those of natives, but did not fall below average native responses even in low light. Surprisingly, neither group showed direct trait or growth responses to soil N additions. However, invasive species showed increased photosynthetic nitrogen use efficiencies with decreasing N availability, while that of natives remained constant. Although invader advantage over natives was amplified in higher resource conditions in this forest, our results indicate that some invasive species can maintain physiological advantages over co-occurring natives regardless of resource conditions. PMID:27220204

  3. Curvilinear Effects of Invasive Plants on Plant Diversity: Plant Community Invaded by Sphagneticola trilobata

    PubMed Central

    Zhai, De-Li; Chen, Si-Chong; Si, Chun-Can; Huang, Ping; Wang, Rui-Ping; Zhong, Qiong-Xin; Du, Dao-Lin

    2014-01-01

    The effects of invasive plants on the species diversity of plant communities are controversial, showing either a positive or negative linear relationship. Based on community data collected from forty 5 m5 m plots invaded by Sphagneticola trilobata in eight cities across Hainan Island, China, we found S. trilobata decreased plant community diversity once its cover was beyond 10%. We demonstrated that the effects of invasive/native plants on the plant diversity of communities invaded by S. trilobata were curvilinear. These effects, which showed peaks under different degrees of vegetation cover, appeared not only for S. trilobata and all invasive plants, but also for all native plants. Invasive plants primarily had negative effects on plant diversity when they became abundant at a much lower cover level (less than 35%), compared with the native plants (over 60%). Thus, it is necessary to distinguish a range for assessing the effects of plants, especially invasive plants. Our results also confirmed that the invasion intensity of invasive alien plants increased with the intensity of local economic development. We highlight and further discuss the critical importance of curvilinear effects of biological invasion to provide ideas regarding the conservation of local biodiversity and the management of invasive plants. PMID:25426856

  4. Life History Variation in Invading Applesnails (Pomacea canaliculata) May Pose Ecological Threats to Wetlands

    NASA Astrophysics Data System (ADS)

    Marfurt, R. K.; Boland, B. B.; Burks, R. L.

    2005-05-01

    In native habitats, channeled applesnails (Pomacea canaliculata) graze periphyton. However, casual observations from introduced populations suggest these invaders show variation in feeding ecology, predator response and life history strategies. Attempts to predict this consumer influence on ecosystem function suffer from a lack of basic data. We tested how salinity affected snail mortality. Both adults and hatchlings tolerated salinity levels up to 8 ppt. Adult feeding on lettuce increased significantly at 8 ppt compared to 0 ppt (p = 0.002), while hatchling consumption of algae did not vary (p = 0.284). To see how these consumers responded to predators from the invaded ecosystem, we tested behavioural responses to predatory cues from fish, turtles, crayfish and adult applesnails. Results indicated that fish and crayfish prompted similar predator-avoidance behaviors in hatchlings (p's < 0.05) and that hatchling response changed over time. Consumption rates of juvenile redear sunfish did not vary (x2, p > 0.05) between native (ramshorn) and exotic applesnails, whereas adult fish consumed more applesnails (x2, p < 0.001). Our current efforts focus on examining if predator presence or macrophyte choice alters applesnail feeding rates. Research providing insight into the basic ecology of applesnails can foster management efforts at the ecosystem scale.

  5. Invasion Expansion: Time since introduction best predicts global ranges of marine invaders

    PubMed Central

    Byers, James E.; Smith, Rachel S.; Pringle, James M.; Clark, Graeme F.; Gribben, Paul E.; Hewitt, Chad L.; Inglis, Graeme J.; Johnston, Emma L.; Ruiz, Gregory M.; Stachowicz, John J.; Bishop, Melanie J.

    2015-01-01

    Strategies for managing biological invasions are often based on the premise that characteristics of invading species and the invaded environment are key predictors of the invader’s distribution. Yet, for either biological traits or environmental characteristics to explain distribution, adequate time must have elapsed for species to spread to all potential habitats. We compiled and analyzed a database of natural history and ecological traits of 138 coastal marine invertebrate species, the environmental conditions at sites to which they have been introduced, and their date of first introduction. We found that time since introduction explained the largest fraction (20%) of the variability in non-native range size, while traits of the species and environmental variables had significant, but minimal, influence on non-native range size. The positive relationship between time since introduction and range size indicates that non-native marine invertebrate species are not at equilibrium and are still spreading, posing a major challenge for management of coastal ecosystems. PMID:26227803

  6. Conciliation biology: the eco-evolutionary management of permanently invaded biotic systems

    PubMed Central

    Carroll, Scott P

    2011-01-01

    Biotic invaders and similar anthropogenic novelties such as domesticates, transgenics, and cancers can alter ecology and evolution in environmental, agricultural, natural resource, public health, and medical systems. The resulting biological changes may either hinder or serve management objectives. For example, biological control and eradication programs are often defeated by unanticipated resistance evolution and by irreversibility of invader impacts. Moreover, eradication may be ill-advised when nonnatives introduce beneficial functions. Thus, contexts that appear to call for eradication may instead demand managed coexistence of natives with nonnatives, and yet applied biologists have not generally considered the need to manage the eco-evolutionary dynamics that commonly result from interactions of natives with nonnatives. Here, I advocate a conciliatory approach to managing systems where novel organisms cannot or should not be eradicated. Conciliatory strategies incorporate benefits of nonnatives to address many practical needs including slowing rates of resistance evolution, promoting evolution of indigenous biological control, cultivating replacement services and novel functions, and managing native–nonnative coevolution. Evolutionary links across disciplines foster cohesion essential for managing the broad impacts of novel biotic systems. Rather than signaling defeat, conciliation biology thus utilizes the predictive power of evolutionary theory to offer diverse and flexible pathways to more sustainable outcomes. PMID:25567967

  7. Pseudomonas aeruginosa Activates PKC-Alpha to Invade Middle Ear Epithelial Cells

    PubMed Central

    Mittal, Rahul; Grati, M’hamed; Yan, Denise; Liu, Xue Z.

    2016-01-01

    Otitis media (OM) is a group of complex inflammatory disorders affecting the middle ear which can be acute or chronic. Chronic suppurative otitis media (CSOM) is a form of chronic OM characterized by tympanic membrane perforation and discharge. Despite the significant impact of CSOM on human population, it is still an understudied and unexplored research area. CSOM is a leading cause of hearing loss and life-threatening central nervous system complications. Bacterial exposure especially Pseudomonas aeruginosa is the most common cause of CSOM. Our previous studies have demonstrated that P. aeruginosa invades human middle ear epithelial cells (HMEECs). However, molecular mechanisms leading to bacterial invasion of HMEECs are not known. The aim of this study is to characterize the role of PKC pathway in the ability of P. aeruginosa to colonize HMEECs. We observed that otopathogenic P. aeruginosa activates the PKC pathway, specifically phosphorylation of PKC-alpha (PKC-α) in HMEECs. The ability of otopathogenic P. aeruginosa to phosphorylate PKC-α depends on bacterial OprF expression. The activation of PKC-α was associated with actin condensation. Blocking the PKC pathway attenuated the ability of bacteria to invade HMEECs and subsequent actin condensation. This study, for the first time, demonstrates that the host PKC-α pathway is involved in invasion of HMEECs by P. aeruginosa and subsequently to cause OM. Characterizing the role of the host signaling pathway in the pathogenesis of CSOM will provide novel avenues to design effective treatment modalities against the disease. PMID:26973629

  8. Mya arenaria — an ancient invader of the North Sea coast

    NASA Astrophysics Data System (ADS)

    Strasser, Matthias

    1998-09-01

    Mya arenaria currently occupies a wide geographical range in the northern hemisphere, on both coasts of the Atlantic as well as on the Pacific east coast. Some authors claim it also occurs on the Pacific west coast. The species originated in the Pacific during the Miocene and was already present on both Atlantic coasts in the Pliocene. However, it died out on the east coasts of the Pacific and the Atlantic during glaciation of the Pleistocene. With the aid of man it was reintroduced to the North Sea some 400-700 years ago and to the East Pacific last century. In the 1960s it was also introduced to the Black Sea. M. arenaria invaded new habitats by different modes: (1) natural range expansion (2) intentional as plantings, (3) unintentional as a ballast species and (4) unintentional as a byproduct of oyster transplants. Properties that may favor its wide range of distribution and invading success are: high fecundity; planktonic dispersal stages and life stages that lend itself to unintentional transport by humans; a broad spectrum of habitat and food preference; tolerance of a wide range of environmental conditions such as salinity and temperature; longevity, and perhaps relatively large size.

  9. Integrating novel chemical weapons and evolutionarily increased competitive ability in success of a tropical invader.

    PubMed

    Zheng, Yu-Long; Feng, Yu-Long; Zhang, Li-Kun; Callaway, Ragan M; Valiente-Banuet, Alfonso; Luo, Du-Qiang; Liao, Zhi-Yong; Lei, Yan-Bao; Barclay, Gregor F; Silva-Pereyra, Carlos

    2015-02-01

    The evolution of increased competitive ability (EICA) hypothesis and the novel weapons hypothesis (NWH) are two non-mutually exclusive mechanisms for exotic plant invasions, but few studies have simultaneously tested these hypotheses. Here we aimed to integrate them in the context of Chromolaena odorata invasion. We conducted two common garden experiments in order to test the EICA hypothesis, and two laboratory experiments in order to test the NWH. In common conditions, C. odorata plants from the nonnative range were better competitors but not larger than plants from the native range, either with or without the experimental manipulation of consumers. Chromolaena odorata plants from the nonnative range were more poorly defended against aboveground herbivores but better defended against soil-borne enemies. Chromolaena odorata plants from the nonnative range produced more odoratin (Eupatorium) (a unique compound of C. odorata with both allelopathic and defensive activities) and elicited stronger allelopathic effects on species native to China, the nonnative range of the invader, than on natives of Mexico, the native range of the invader. Our results suggest that invasive plants may evolve increased competitive ability after being introduced by increasing the production of novel allelochemicals, potentially in response to naïve competitors and new enemy regimes. PMID:25367824

  10. Did Vertigo Kill America's Forgotten Astronaut?

    NASA Technical Reports Server (NTRS)

    Bendrick, Gregg A.; Merlin, Peter W.

    2007-01-01

    On November 15, 1967, U.S. Air Force test pilot Major Michael J. Adams was killed while flying the X-15 rocket-propelled research vehicle in a parabolic spaceflight profile. This flight was part of a joint effort with NASA. An electrical short in one of the experiments aboard the vehicle caused electrical transients, resulting in excessive workload by the pilot. At altitude Major Adams inappropriately initiated a flat spin that led to a series of unusual aircraft attitudes upon atmospheric re-entry, ultimately causing structural failure of the airframe. Major Adams was known to experience vertigo (i.e. spatial disorientation) while flying the X-15, but all X-15 pilots most likely experienced vertigo (i.e. somatogravic, or "Pitch-Up", illusion) as a normal physiologic response to the accelerative forces involved. Major Adams probably experienced vertigo to a greater degree than did others, since prior aeromedical testing for astronaut selection at Brooks AFB revealed that he had an unusually high degree of labyrinthine sensitivity. Subsequent analysis reveals that after engine burnout, and through the zenith of the flight profile, he likely experienced the oculoagravic ("Elevator") illusion. Nonetheless, painstaking investigation after the mishap revealed that spatial disorientation (Type II, Recognized) was NOT the cause, but rather, a contributing factor. The cause was in fact the misinterpretation of a dual-use flight instrument (i.e. Loss of Mode Awareness), resulting in confusion between yaw and roll indications, with subsequent flight control input that was inappropriate. Because of the altitude achieved on this flight, Major Adams was awarded Astronaut wings posthumously. Understanding the potential for spatial disorientation, particularly the oculoagravic illusion, associated with parabolic spaceflight profiles, and understanding the importance of maintaining mode awareness in the context of automated cockpit design, are two lessons that have direct application to the commercial space industry today.

  11. Kill a brand, keep a customer.

    PubMed

    Kumar, Nirmalya

    2003-12-01

    Most brands don't make much money. Year after year, businesses generate 80% to 90% of their profits from less than 20% of their brands. Yet most companies tend to ignore loss-making brands, unaware of the hidden costs they incur. That's because executives believe it's easy to erase a brand; they have only to stop investing in it, they assume, and it will die a natural death. But they're wrong. When companies drop brands clumsily, they antagonize loyal customers: Research shows that seven times out of eight, when firms merge two brands, the market share of the new brand never reaches the combined share of the two original ones. It doesn't have to be that way. Smart companies use a four-step process to kill brands methodically. First, CEOs make the case for rationalization by getting groups of senior executives to conduct joint audits of the brand portfolio. These audits make the need to prune brands apparent throughout the organization. In the next stage, executives need to decide how many brands will be retained, which they do either by setting broad parameters that all brands must meet or by identifying the brands they need in order to cater to all the customer segments in their markets. Third, executives must dispose of the brands they've decided to drop, deciding in each case whether it is appropriate to merge, sell, milk, or just eliminate the brand outright. Finally, it's critical that executives invest the resources they've freed to grow the brands they've retained. Done right, dropping brands will result in a company poised for new growth from the source where it's likely to be found--its profitable brands. PMID:14712547

  12. Can Nanomedicines Kill Cancer Stem Cells?

    PubMed Central

    Zhao, Yi; Alakhova, Daria Y.; Kabanov, Alexander V.

    2014-01-01

    Most tumors are heterogeneous and many cancers contain small population of highly tumorigenic and intrinsically drug resistant cancer stem cells (CSCs). Like normal stem cell, CSCs have ability to self-renew and differentiate to other tumor cell types. They are believed to be a source for drug resistance, tumor recurrence and metastasis. CSCs often overexpress drug efflux transporters, spend most of their time in non-dividing G0 cell cycle state, and therefore, can escape the conventional chemotherapies. Thus, targeting CSCs is essential for developing novel therapies to prevent cancer relapse and emerging of drug resistance. Nanocarrier-based therapeutic agents (nanomedicines) have been used to achieve longer circulation times, better stability and bioavailability over current therapeutics. Recently, some groups have successfully applied nanomedicines to target CSCs to eliminate the tumor and prevent its recurrence. These approaches include 1) delivery of therapeutic agents (small molecules, siRNA, antibodies) that affect embryonic signaling pathways implicated in self-renewal and differentiation in CSCs, 2) inhibiting drug efflux transporters in an attempt to sensitize CSCs to therapy, 3) targeting metabolism in CSCs through nanoformulated chemicals and field-responsive magnetic nanoparticles and carbon nanotubes, and 4) disruption of multiple pathways in drug resistant cells using combination of chemotherapeutic drugs with amphiphilic Pluronic block copolymers. Despite clear progress of these studies the challenges of targeting CSCs by nanomedicines still exist and leave plenty of room for improvement and development. This review summarizes biological processes that are related to CSCs, overviews the current state of anti-CSCs therapies, and discusses state-of-the-art nanomedicine approaches developed to kill CSCs. PMID:24120657

  13. Killing of Leishmania parasites in activated murine macrophages is based on an L-arginine-dependent process that produces nitrogen derivatives

    SciTech Connect

    Maul, J.R.; Ransijn, A.; Buchmueller-Rouiller, Y. )

    1991-01-01

    The experiments described in this report were aimed at determining whether L-arginine (L-arg)-derived nitrogen oxidation products (nitric oxide, nitrous acid, nitrites) are involved in the intracellular killing of Leishmania parasites by activated murine macrophages in vitro. Peritoneal or bone marrow-derived macrophages were infected with L. enriettii or L. major, then activated by exposure to recombinant murine interferon-gamma or to macrophage activating factor (MAF)-rich media in the presence of lipopolysaccharide. Activation of macrophages in regular (i.e., arginine-containing) culture medium led to complete destruction of the microorganisms within 24 h (L. enriettii) or 48 h (L. major), concomitant with accumulation of nitrites (NO2-) in the culture fluids. When macrophage activation was carried out in L-arg-free medium, however, neither parasite killing nor NO2- production was obtained. A similar inhibition of macrophage leishmanicidal activity and of NO2- release was observed using media treated with arginase (which converts L-arg to urea and ornithine), or supplemented with NG-monomethyl-L-arg or guanidine (which inhibit the conversion of L-arg to nitrogen oxidation products). In all these situations, an excellent correlation between the levels of NO2- production by macrophages and intracellular killing of Leishmania was observed, whereas no strict correlation was detectable between leishmanicidal activity and superoxide production. Intracellular parasite killing by activated macrophages could be prevented by addition of iron salts to the incubation fluids. Incubation of free parasites with NaNO2 at acid pH led to immobilisation, multiplication arrest, and morphological degeneration of the microorganisms. Similarly, exposure of infected cells to NaNO2 led to killing of the intracellular parasite without affecting macrophage viability.

  14. Local climatic adaptation in a widespread microorganism

    PubMed Central

    Leducq, Jean-Baptiste; Charron, Guillaume; Samani, Pedram; Dubé, Alexandre K.; Sylvester, Kayla; James, Brielle; Almeida, Pedro; Sampaio, José Paulo; Hittinger, Chris Todd; Bell, Graham; Landry, Christian R.

    2014-01-01

    Exploring the ability of organisms to locally adapt is critical for determining the outcome of rapid climate changes, yet few studies have addressed this question in microorganisms. We investigated the role of a heterogeneous climate on adaptation of North American populations of the wild yeast Saccharomyces paradoxus. We found abundant among-strain variation for fitness components across a range of temperatures, but this variation was only partially explained by climatic variation in the distribution area. Most of fitness variation was explained by the divergence of genetically distinct groups, distributed along a north–south cline, suggesting that these groups have adapted to distinct climatic conditions. Within-group fitness components were correlated with climatic conditions, illustrating that even ubiquitous microorganisms locally adapt and harbour standing genetic variation for climate-related traits. Our results suggest that global climatic changes could lead to adaptation to new conditions within groups, or changes in their geographical distributions. PMID:24403328

  15. Distribution of Aldoxime Dehydratase in Microorganisms

    PubMed Central

    Kato, Yasuo; Ooi, Ryoko; Asano, Yasuhisa

    2000-01-01

    The distribution of phenylacetaldoxime-degrading and pyridine-3-aldoxime-degrading ability was examined with intact cells of 975 microorganisms, including 45 genera of bacteria, 11 genera of actinomyces, 22 genera of yeasts, and 37 genera of fungi, by monitoring the decrease of the aldoximes by high-pressure liquid chromatography. The abilities were found to be widely distributed in bacteria, actinomyces, fungi, and some yeasts: 98 and 107 strains degraded phenylacetaldoxime and pyridine-3-aldoxime, respectively. All of the active strains exhibited not only the aldoxime-dehydration activity to form nitrile but also nitrile-hydrolyzing activity. On the other hand, all of 19 nitrile-degrading microorganisms (13 species, 7 genera) were found to exhibit aldoxime dehydration activity. It is shown that aldoxime dehydratase and nitrile-hydrolyzing activities are widely distributed among 188 aldoxime and 19 nitrile degraders and that the enzymes were induced by aldoximes or nitriles. PMID:10831401

  16. How could haloalkaliphilic microorganisms contribute to biotechnology?

    PubMed

    Zhao, Baisuo; Yan, Yanchun; Chen, Shulin

    2014-11-01

    Haloalkaliphiles are microorganisms requiring Na(+) concentrations of at least 0.5 molL(-1) and an alkaline pH of 9 for optimal growth. Their unique features enable them to make significant contributions to a wide array of biotechnological applications. Organic compatible solutes produced by haloalkaliphiles, such as ectoine and glycine betaine, are correlated with osmoadaptation and may serve as stabilizers of intracellular proteins, salt antagonists, osmoprotectants, and dermatological moisturizers. Haloalkaliphiles are an important source of secondary metabolites like rhodopsin, polyhydroxyalkanoates, and exopolysaccharides that play essential roles in biogeocycling organic compounds. These microorganisms also can secrete unique exoenzymes, including proteases, amylases, and cellulases, that are highly active and stable in extreme haloalkaline conditions and can be used for the production of laundry detergent. Furthermore, the unique metabolic pathways of haloalkaliphiles can be applied in the biodegradation and (or) biotransformation of a broad range of toxic industrial pollutants and heavy metals, in wastewater treatment, and in the biofuel industry. PMID:25372346

  17. Solubilization of Australian lignites by microorganisms

    SciTech Connect

    Catcheside, D.E.A.; Mallett, K.J.; Cox, R.E.

    1988-01-01

    Australia has substantial lignite deposits, particularly in the Latrobe Valley in Victoria where 4.10/sup 10/ tons are accessible with available technologies. The authors have investigated the susceptibility of these coal to solubilization by microorganisms, including species additional to those already identified as active on North American lignites. The data presented here show that acid oxidized lignites from the Latrobe Valley are solubilized by each of seven species of microorganisms previously found to be active on Leonardite and oxidized North American lignites. These are the wood rot fungi: Trametes versicolor, Poria placenta and Phanerochaete chrysosporium, the lignin degrading prokaryote Streptomyces viridosporus and three fungi isolated from lignite in Mississippi: Candida ML-13, Cunninghamelia YML-1 and Penicillium waksmanii.

  18. UV inactivation of pathogenic and indicator microorganisms

    SciTech Connect

    Chang, J.C.; Ossoff, S.F.; Lobe, D.C.; Dorfman, M.H.; Dumais, C.M.; Qualls, R.G.; Johnson, J.D.

    1985-06-01

    Survival was measured as a function of the dose of germicidal UV light for the bacteria Escherichia coli, Salmonella typhi, Shigella sonnei, Streptococcus faecalis, Staphylococcus aureus, and Bacillus subtilis spores, the enteric viruses poliovirus type 1 and simian rotavirus SA11, the cysts of the protozoan Acanthamoeba castellanii, as well as for total coliforms and standard plate count microorganisms from secondary effluent. The doses of UV light necessary for a 99.9% inactivation of the cultured vegetative bacteria, total coliforms, and standard plate count microorganisms were comparable. However, the viruses, the bacterial spores, and the amoebic cysts required about 3 to 4 times, 9 times, and 15 times, respectively, the dose required for E. coli. These ratios covered a narrower relative dose range than that previously reported for chlorine disinfection of E. coli, viruses, spores, and cysts.

  19. Microorganisms detection on substrates using QCL spectroscopy

    NASA Astrophysics Data System (ADS)

    Padilla-Jiménez, Amira C.; Ortiz-Rivera, William; Castro-Suarez, John R.; Ríos-Velázquez, Carlos; Vázquez-Ayala, Iris; Hernández-Rivera, Samuel P.

    2013-05-01

    Recent investigations have focused on the improvement of rapid and accurate methods to develop spectroscopic markers of compounds constituting microorganisms that are considered biological threats. Quantum cascade lasers (QCL) systems have revolutionized many areas of research and development in defense and security applications, including his area of research. Infrared spectroscopy detection based on QCL was employed to acquire mid infrared (MIR) spectral signatures of Bacillus thuringiensis (Bt), Escherichia coli (Ec) and Staphylococcus epidermidis (Se), which were used as biological agent simulants of biothreats. The experiments were carried out in reflection mode on various substrates such as cardboard, glass, travel baggage, wood and stainless steel. Chemometrics statistical routines such as principal component analysis (PCA) regression and partial least squares-discriminant analysis (PLS-DA) were applied to the recorded MIR spectra. The results show that the infrared vibrational techniques investigated are useful for classification/detection of the target microorganisms on the types of substrates studied.

  20. Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

    SciTech Connect

    Daniel P. Molloy

    2004-02-24

    The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

  1. Special Killing forms on toric Sasaki-Einstein manifolds

    NASA Astrophysics Data System (ADS)

    Slesar, Vladimir; Visinescu, Mihai; Vîlcu, Gabriel Eduard

    2014-12-01

    In this paper we study the interplay between complex coordinates on the Calabi-Yau metric cone and the special Killing forms on the toric Sasaki-Einstein manifold. First, we give a procedure to locally construct the special Killing forms. Finally, we exemplify the general scheme in the case of the five-dimensional {{Y}p,q} spaces, identifying the additional special Killing 2-forms which were previously obtained using a different method by Visinescu (2012 Mod. Phys. Lett. A 27 1250217).

  2. HIV transcription is induced with some forms of cell killing

    SciTech Connect

    Woloschak, G.E.; Schreck, S.; Panozzo, J.; Chang-Liu, C.-M.; Libertin, C.R.

    1996-11-01

    Using HeLa cells stably transfected with an HIV-LTR-CAT construct`, we demonstrated a peak in CAT induction that occurs in viable (but not necessarily cell-division-competent) cells 24 h following exposure to some cell-killing agents. {Gamma} rays were the only cell-killing agent which did not induce HIV transcription; this can be attributed to the fact that {gamma}-ray-induced apoptotic death requires function p53, which is missing in HeLa cells. For all other agents, HIV-LTR induction was dose-dependent and correlated with the amount of cell killing that occurred in the culture.

  3. Microorganism Utilization for Synthetic Milk Production

    NASA Technical Reports Server (NTRS)

    Morford, Megan A.; Khodadad, Christina Louise; Spencer, LaShelle E.; Richards, Jeffrey T.; Strayer, Richard F.; Caro, Janicce; Hummerick, Mary; Birmele, Michele N.; Wheeler, Raymond M.

    2014-01-01

    A desired architecture for long duration spaceflight, such as aboard the International Space Station (ISS) or for future missions to Mars, is to provide a supply of fresh food crops for the astronauts. However, some crops can create a high proportion of inedible plant waste. The main goal of this project was to produce the components of milk (sugar, lipid, protein) from inedible plant waste by utilizing microorganisms (fungi, yeast, bacteria). Of particular interest was utilizing the valuable polysaccharide, cellulose, found in plant waste, to naturally fuel- through microorganism cellular metabolism- the creation of sugar (glucose), lipid (milk fat), and protein (casein) to produce a synthetic edible food product. Environmental conditions such as pH, temperature, carbon source, aeration, and choice microorganisms were optimized in the laboratory and the desired end-products, sugars and lipids, were analyzed. Trichoderma reesei, a known cellulolytic fungus, was utilized to drive the production of glucose, with the intent that the produced glucose would serve as the carbon source for milk fat production and be a substitute for the milk sugar lactose. Lipid production would be carried out by Rhodosporidium toruloides, yeast known to accumulate those lipids that are typically found in milk fat. Results showed that glucose and total lipid content were below what was expected during this phase of experimentation. In addition, individual analysis of six fatty acids revealed that the percentage of each fatty acid was lower than naturally produced bovine milk. Overall, this research indicates that microorganisms could be utilized to breakdown inedible solid waste to produce useable products.

  4. Mass Spectrometer for Airborne Micro-Organisms

    NASA Technical Reports Server (NTRS)

    Sinha, M. P.; Friedlander, S. K.

    1986-01-01

    Bacteria and other micro-organisms identified continously with aid of new technique for producing samples for mass spectrometer. Technique generates aerosol of organisms and feeds to spectrometer. Given species of organism produces characteristic set of peaks in mass spectrum and thereby identified. Technique useful for monitoring bacterial makeup in environmental studies and in places where cleanliness is essential, such as hospital operating rooms, breweries, and pharmaceutical plants.

  5. Consolidated bioprocessing method using thermophilic microorganisms

    DOEpatents

    Mielenz, Jonathan Richard

    2016-02-02

    The present invention is directed to a method of converting biomass to biofuel, and particularly to a consolidated bioprocessing method using a co-culture of thermophilic and extremely thermophilic microorganisms which collectively can ferment the hexose and pentose sugars produced by degradation of cellulose and hemicelluloses at high substrate conversion rates. A culture medium therefor is also provided as well as use of the methods to produce and recover cellulosic ethanol.

  6. The enemy of my enemy is my friend: intraguild predation between invaders and natives facilitates coexistence with shared invasive prey

    PubMed Central

    MacNeil, Calum; Dick, Jaimie T. A.

    2014-01-01

    Understanding and predicting the outcomes of biological invasions is challenging where multiple invader and native species interact. We hypothesize that antagonistic interactions between invaders and natives could divert their impact on subsequent invasive species, thus facilitating coexistence. From field data, we found that, when existing together in freshwater sites, the native amphipod Gammarus duebeni celticus and a previous invader G. pulex appear to facilitate the establishment of a second invader, their shared prey Crangonyx pseudogracilis. Indeed, the latter species was rarely found at sites where each Gammarus species was present on its own. Experiments indicated that this may be the result of G. d. celticus and G. pulex engaging in more intraguild predation (IGP) than cannibalism; when the ‘enemy’ of either Gammarus species was present, that is, the other Gammarus species, C. pseudogracilis significantly more often escaped predation. Thus, the presence of mutual enemies and the stronger inter- than intraspecific interactions they engage in can facilitate other invaders. With some invasive species such as C. pseudogracilis having no known detrimental effects on native species, and indeed having some positive ecological effects, we also conclude that some invasions could promote biodiversity and ecosystem functioning. PMID:25122739

  7. The enemy of my enemy is my friend: intraguild predation between invaders and natives facilitates coexistence with shared invasive prey.

    PubMed

    MacNeil, Calum; Dick, Jaimie T A

    2014-08-01

    Understanding and predicting the outcomes of biological invasions is challenging where multiple invader and native species interact. We hypothesize that antagonistic interactions between invaders and natives could divert their impact on subsequent invasive species, thus facilitating coexistence. From field data, we found that, when existing together in freshwater sites, the native amphipod Gammarus duebeni celticus and a previous invader G. pulex appear to facilitate the establishment of a second invader, their shared prey Crangonyx pseudogracilis. Indeed, the latter species was rarely found at sites where each Gammarus species was present on its own. Experiments indicated that this may be the result of G. d. celticus and G. pulex engaging in more intraguild predation (IGP) than cannibalism; when the 'enemy' of either Gammarus species was present, that is, the other Gammarus species, C. pseudogracilis significantly more often escaped predation. Thus, the presence of mutual enemies and the stronger inter- than intraspecific interactions they engage in can facilitate other invaders. With some invasive species such as C. pseudogracilis having no known detrimental effects on native species, and indeed having some positive ecological effects, we also conclude that some invasions could promote biodiversity and ecosystem functioning. PMID:25122739

  8. Protein Languages Differ Depending on Microorganism Lifestyle

    PubMed Central

    Grzymski, Joseph J.; Marsh, Adam G.

    2014-01-01

    Few quantitative measures of genome architecture or organization exist to support assumptions of differences between microorganisms that are broadly defined as being free-living or pathogenic. General principles about complete proteomes exist for codon usage, amino acid biases and essential or core genes. Genome-wide shifts in amino acid usage between free-living and pathogenic microorganisms result in fundamental differences in the complexity of their respective proteomes that are size and gene content independent. These differences are evident across broad phylogenetic groups–a result of environmental factors and population genetic forces rather than phylogenetic distance. A novel comparative analysis of amino acid usage–utilizing linguistic analyses of word frequency in language and text–identified a global pattern of higher peptide word repetition in 376 free-living versus 421 pathogen genomes across broad ranges of genome size, G+C content and phylogenetic ancestry. This imprint of repetitive word usage indicates free-living microorganisms have a bias for repetitive sequence usage compared to pathogens. These findings quantify fundamental differences in microbial genomes relative to life-history function. PMID:24828817

  9. Complete nitrification by a single microorganism.

    PubMed

    van Kessel, Maartje A H J; Speth, Daan R; Albertsen, Mads; Nielsen, Per H; Op den Camp, Huub J M; Kartal, Boran; Jetten, Mike S M; Lücker, Sebastian

    2015-12-24

    Nitrification is a two-step process where ammonia is first oxidized to nitrite by ammonia-oxidizing bacteria and/or archaea, and subsequently to nitrate by nitrite-oxidizing bacteria. Already described by Winogradsky in 1890, this division of labour between the two functional groups is a generally accepted characteristic of the biogeochemical nitrogen cycle. Complete oxidation of ammonia to nitrate in one organism (complete ammonia oxidation; comammox) is energetically feasible, and it was postulated that this process could occur under conditions selecting for species with lower growth rates but higher growth yields than canonical ammonia-oxidizing microorganisms. Still, organisms catalysing this process have not yet been discovered. Here we report the enrichment and initial characterization of two Nitrospira species that encode all the enzymes necessary for ammonia oxidation via nitrite to nitrate in their genomes, and indeed completely oxidize ammonium to nitrate to conserve energy. Their ammonia monooxygenase (AMO) enzymes are phylogenetically distinct from currently identified AMOs, rendering recent acquisition by horizontal gene transfer from known ammonia-oxidizing microorganisms unlikely. We also found highly similar amoA sequences (encoding the AMO subunit A) in public sequence databases, which were apparently misclassified as methane monooxygenases. This recognition of a novel amoA sequence group will lead to an improved understanding of the environmental abundance and distribution of ammonia-oxidizing microorganisms. Furthermore, the discovery of the long-sought-after comammox process will change our perception of the nitrogen cycle. PMID:26610025

  10. Biomining: metal recovery from ores with microorganisms.

    PubMed

    Schippers, Axel; Hedrich, Sabrina; Vasters, Jürgen; Drobe, Malte; Sand, Wolfgang; Willscher, Sabine

    2014-01-01

    Biomining is an increasingly applied biotechnological procedure for processing of ores in the mining industry (biohydrometallurgy). Nowadays the production of copper from low-grade ores is the most important industrial application and a significant part of world copper production already originates from heap or dump/stockpile bioleaching. Conceptual differences exist between the industrial processes of bioleaching and biooxidation. Bioleaching is a conversion of an insoluble valuable metal into a soluble form by means of microorganisms. In biooxidation, on the other hand, gold is predominantly unlocked from refractory ores in large-scale stirred-tank biooxidation arrangements for further processing steps. In addition to copper and gold production, biomining is also used to produce cobalt, nickel, zinc, and uranium. Up to now, biomining has merely been used as a procedure in the processing of sulfide ores and uranium ore, but laboratory and pilot procedures already exist for the processing of silicate and oxide ores (e.g., laterites), for leaching of processing residues or mine waste dumps (mine tailings), as well as for the extraction of metals from industrial residues and waste (recycling). This chapter estimates the world production of copper, gold, and other metals by means of biomining and chemical leaching (bio-/hydrometallurgy) compared with metal production by pyrometallurgical procedures, and describes new developments in biomining. In addition, an overview is given about metal sulfide oxidizing microorganisms, fundamentals of biomining including bioleaching mechanisms and interface processes, as well as anaerobic bioleaching and bioleaching with heterotrophic microorganisms. PMID:23793914

  11. Prokaryotic silicon utilizing microorganisms in the biosphere

    NASA Astrophysics Data System (ADS)

    Gupta, D.; Das, S.

    2012-12-01

    Although a little study has been done to determine the silicon utilizing prokaryotes, our previous experiments indicated that almost all Gram-positive bacteria are silicon utilizing; one of them, Streptococci survived exposure on the lunar surface for a long period in experiment done by others. Our initial experiments with these Gram positive microorganisms showed that there were limited growths of these microorganisms on carbon free silicate medium probably with the help of some carry over carbon and nitrogen during cultivation procedures. However, increase in growth rate after repeated subcultures could not be explained at present. The main groups of prokaryotes which were found silicon utilizing microorganisms were Mycobacterium, Bacillus, Nocardia, Streptomyces, Staphylococcus, Streptococcus, Lactobacillus, and Clostridium. In a another previous study by us when silicon level was studied in such grown up cells on carbon "free" silicate medium by electron prove microanalyser, it was found that silicon in cells grown on carbon "free" silicate medium was much higher (24.9%) than those grown on conventional carbon based medium (0.84%). However, these initial findings are encouraging for our future application of this group of organisms on extraterrestrial surfaces for artificial micro-ecosystem formation. It was found that when electropositive elements are less in extraterrestrial situation, then polymerization of silicon-oxygen profusion may occur easily, particularly in carbon and nitrogen paucity in the rocky worlds of the Universe.

  12. Genomics, metagenomics and proteomics in biomining microorganisms.

    PubMed

    Valenzuela, Lissette; Chi, An; Beard, Simon; Orell, Alvaro; Guiliani, Nicolas; Shabanowitz, Jeff; Hunt, Donald F; Jerez, Carlos A

    2006-01-01

    The use of acidophilic, chemolithotrophic microorganisms capable of oxidizing iron and sulfur in industrial processes to recover metals from minerals containing copper, gold and uranium is a well established biotechnology with distinctive advantages over traditional mining. A consortium of different microorganisms participates in the oxidative reactions resulting in the extraction of dissolved metal values from ores. Considerable effort has been spent in the last years to understand the biochemistry of iron and sulfur compounds oxidation, bacteria-mineral interactions (chemotaxis, quorum sensing, adhesion, biofilm formation) and several adaptive responses allowing the microorganisms to survive in a bioleaching environment. All of these are considered key phenomena for understanding the process of biomining. The use of genomics, metagenomics and high throughput proteomics to study the global regulatory responses that the biomining community uses to adapt to their changing environment is just beginning to emerge in the last years. These powerful approaches are reviewed here since they offer the possibility of exciting new findings that will allow analyzing the community as a microbial system, determining the extent to which each of the individual participants contributes to the process, how they evolve in time to keep the conglomerate healthy and therefore efficient during the entire process of bioleaching. PMID:16288845

  13. Investigation to identify paint coatings resistive to microorganism growth

    NASA Technical Reports Server (NTRS)

    Cooper, C. W.; Kemp, H. T.

    1971-01-01

    All selected coatings contain nutrients that support microbial growth and survival. Incorporation of microbiocidal agents into coatings more susceptible to attack is recommended for improved inhibition of microorganism growth and for increased protection against deterioration of coatings by microorganisms.

  14. MODELING THE FATE OF MICROORGANISMS IN WATER, WASTEWATER, AND SOIL

    EPA Science Inventory

    The natural environment is filled with microorganisms, most of which are natural residents and colonize various ecological niches. These microorganisms either live independently within the environment, or live in association with various host organisms. There also are places and ...

  15. MICROORGANISMS DIE-OFF RATES IN URBAN STORMWATER RUNOFF 2007

    EPA Science Inventory

    Stormwater best management practices (BMPs) are often considered effective tools to mitigate the effects of stormwater pollutants before they are discharged to receiving waters. However, BMP performance for microorganisms removal is not well documented. Microorganisms die-off in...

  16. MICROORGANISMS DIE-OFF RATES IN URBAN STORMWATER RUNOFF 2007

    EPA Science Inventory

    Stormwater best management practices (BMPs) are often considered effective tools to mitigate the effects of stormwater pollutants before they are discharged to receiving waters. However, BMP performance for microorganisms removal is not well documented. Microorganisms die-off in ...

  17. 40 CFR 725.88 - Uses of a microorganism.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information § 725.88 Uses of a microorganism. (a) Assertion of claim. A person who...

  18. Order of inoculation affects the success of co-invading entomopathogenic fungi.

    PubMed

    Zamora-Macorra, E J; Guzmán-Franco, A W; Pell, J K; Alatorre-Rosas, R; Suarez-Espinoza, J

    2012-12-01

    The effect of order of inoculation of Pandora blunckii and Zoophthora radicans co-infecting Plutella xylostella (L.) (Lepidoptera: Plutellidae) was investigated. After co-inoculation, the proportion of larvae infected by either species was greatly reduced compared to when they were inoculated singly. The order of inoculation influenced the final outcome; the isolate inoculated last always killed more larvae than the isolate inoculated first. PMID:23949679

  19. 40 CFR 725.88 - Uses of a microorganism.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Uses of a microorganism. 725.88... CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information 725.88 Uses of a microorganism. (a) Assertion of claim. A person who...

  20. 40 CFR 725.88 - Uses of a microorganism.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Uses of a microorganism. 725.88... CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information § 725.88 Uses of a microorganism. (a) Assertion of claim. A person who...

  1. 40 CFR 725.88 - Uses of a microorganism.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Uses of a microorganism. 725.88... CONTROL ACT REPORTING REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information § 725.88 Uses of a microorganism. (a) Assertion of claim. A person who...

  2. NK cells kill mycobacteria directly by releasing perforin and granulysin.

    PubMed

    Lu, Chia-Chen; Wu, Ting-Shu; Hsu, Ya-Jing; Chang, Chih-Jung; Lin, Chuan-Sheng; Chia, Ju-Hsin; Wu, Tsu-Lan; Huang, Tsung-Teng; Martel, Jan; Ojcius, David M; Young, John D; Lai, Hsin-Chih

    2014-12-01

    Although the mechanisms underlying the cytotoxic effect of NK cells on tumor cells and intracellular bacteria have been studied extensively, it remains unclear how these cells kill extracellular bacterial pathogens. In this study, we examine how human NK cells kill Mycobacterium kansasii and M.tb. The underlying mechanism is contact dependent and requires two cytolytic proteins: perforin and granulysin. Mycobacteria induce enhanced expression of the cytolytic proteins via activation of the NKG2D/NCR cell-surface receptors and intracellular signaling pathways involving ERK, JNK, and p38 MAPKs. These results suggest that NK cells use similar cellular mechanisms to kill both bacterial pathogens and target host cells. This report reveals a novel role for NK cells, perforin, and granulysin in killing mycobacteria and highlights a potential alternative defense mechanism that the immune system can use against mycobacterial infection. PMID:25139289

  3. Antibacterial activity of silver-killed bacteria: the "zombies" effect.

    PubMed

    Wakshlak, Racheli Ben-Knaz; Pedahzur, Rami; Avnir, David

    2015-01-01

    We report a previously unrecognized mechanism for the prolonged action of biocidal agents, which we denote as the zombies effect: biocidally-killed bacteria are capable of killing living bacteria. The concept is demonstrated by first killing Pseudomonas aeruginosa PAO1 with silver nitrate and then challenging, with the dead bacteria, a viable culture of the same bacterium: Efficient antibacterial activity of the killed bacteria is observed. A mechanism is suggested in terms of the action of the dead bacteria as a reservoir of silver, which, due to Le-Chatelier's principle, is re-targeted to the living bacteria. Langmuirian behavior, as well as deviations from it, support the proposed mechanism. PMID:25906433

  4. Heart Disease Now Kills 1 of Every 3 Americans

    MedlinePlus

    ... nlm.nih.gov/medlineplus/news/fullstory_156255.html Heart Disease Now Kills 1 of Every 3 Americans Heart ... deaths in the United States are caused by heart disease, stroke and other heart-related diseases, a report ...

  5. Erythrocyte and leukocyte: two partners in bacteria killing.

    PubMed

    Minasyan, Hayk A

    2014-01-01

    Leukocytes can't perform phagocytosis in blood stream. Blood velocity prevents phagocytosis because there is no time for leukocyte to recognize and catch bacteria. Bloodstream clearance from pathogens is performed by erythrocytes. During motion in bloodstream erythrocytes become charged by triboelectric effect. This charge attracts bacteria and fixes them on the surface of erythrocyte, then bacteria are engulfed and killed by hemoglobin oxygen. In bloodstream, leukocyte thin-wrinkled elastic membrane can't be charged by triboelectric effect and so leukocyte can't catch bacteria by means of electrostatic attraction force. Leukocytes engulf and kill bacteria out of blood circulatory system: in tissues, lymph nodes, slow velocity lymph, etc. Erythrocyte and leukocyte are bactericidal partners: the first kills bacteria in bloodstream, the second kills them locally, out of blood circulation. PMID:25259410

  6. [Killing and dignity of animals: a problem for veterinarians?].

    PubMed

    Fahrion; Dürr, S; Doherr, M G; Hartnack, S; Kunzmann, P

    2011-05-01

    Killing of animals is an important task to be performed by veterinarians. Killing decisions and their implementation often raise ethical questions. As a result of an interdisciplinary workshop targeting the subject "killing of animals" with veterinarians and ethicists, a three-dimensional dimension scheme was developed. Whereas the first two dimensions are focused on the animal's past and future life and are discussed with regard to life quality and life accomplishment (the "telos"), the third dimension incorporates the reason to kill and may integrate the concept of dignity. This form of dignity and the weighing of interests are applied to example scenarios and the resulting responsibilities of veterinarians and society are discussed. PMID:21696009

  7. Surface structure influences contact killing of bacteria by copper

    PubMed Central

    Zeiger, Marco; Solioz, Marc; Edongué, Hervais; Arzt, Eduard; Schneider, Andreas S

    2014-01-01

    Copper kills bacteria rapidly by a mechanism that is not yet fully resolved. The antibacterial property of copper has raised interest in its use in hospitals, in place of plastic or stainless steel. On the latter surfaces, bacteria can survive for days or even weeks. Copper surfaces could thus provide a powerful accessory measure to curb nosocomial infections. We here investigated the effect of the copper surface structure on the efficiency of contact killing of Escherichia coli, an aspect which so far has received very little attention. It was shown that electroplated copper surfaces killed bacteria more rapidly than either polished copper or native rolled copper. The release of ionic copper was also more rapid from electroplated copper compared to the other materials. Scanning electron microscopy revealed that the bacteria nudged into the grooves between the copper grains of deposited copper. The findings suggest that, in terms of contact killing, more efficient copper surfaces can be engineered. PMID:24740976

  8. Hidden symmetries and killing tensors on curved spaces

    SciTech Connect

    Ianus, S.; Visinescu, M.; Vilcu, G. E.

    2010-11-15

    Higher-order symmetries corresponding to Killing tensors are investigated. The intimate relation between Killing-Yano tensors and nonstandard supersymmetries is pointed out. In the Dirac theory on curved spaces, Killing-Yano tensors generate Dirac-type operators involved in interesting algebraic structures as dynamical algebras or even infinite dimensional algebras or superalgebras. The general results are applied to space-times which appear in modern studies. One presents the infinite dimensional superalgebra of Dirac type operators on the 4-dimensional Euclidean Taub-NUT space that can be seen as a twisted loop algebra. The existence of the conformal Killing-Yano tensors is investigated for some spaces with mixed 3-Sasakian structures.

  9. Potassium Channels Mediate Killing by Human Natural Killer Cells

    NASA Astrophysics Data System (ADS)

    Schlichter, Lyanne; Sidell, Neil; Hagiwara, Susumu

    1986-01-01

    Human natural killer (NK) cells in peripheral blood spontaneously recognize and kill a wide variety of target cells. It has been suggested that ion channels are involved in the killing process because there is a Ca-dependent stage and because killing by presensitized cytotoxic T lymphocytes, which in many respects resembles NK killing, is associated with changes in K and Na transport in the target cell. However, no direct evidence exists for ion channels in NK cells or in their target cells. Using the whole-cell variation of the patch-clamp technique, we found a voltage-dependent potassium (K+) current in NK cells. The K+ current was reduced in a dose-dependent manner by the K-channel blockers 4-aminopyridine and quinidine and by the traditional Ca-channel blockers verapamil and Cd2+. We tested the effects of ion-channel blockers on killing of two commonly used target cell lines: K562, which is derived from a human myeloid leukemia, and U937, which is derived from a human histiocytic leukemia. Killing of K562 target cells, determined in a standard 51Cr-release assay, was inhibited in a dose-dependent manner by verapamil, quinidine, Cd2+, and 4-aminopyridine at concentrations comparable to those that blocked the K+ current in NK cells. In K562 target cells only a voltage-dependent Na+ current was found and it was blocked by concentrations of tetrodotoxin that had no effect on killing. Killing of U937 target cells was also inhibited by the two ion-channel blockers tested, quinidine and verapamil. In this cell line only a small K+ current was found that was similar to the one in NK cells. We could not find any evidence of a Ca2+ current in target cells or in NK cells; therefore, our results cannot explain the Ca dependence of killing. Our findings show that there are K channels in NK cells and that these channels play a necessary role in the killing process. In contrast, the endogenous channel type in the target cell is probably not a factor in determining target cell sensitivity to natural killing.

  10. Conformal Killing Vectors in LRS Bianchi Type V Spacetimes

    NASA Astrophysics Data System (ADS)

    Suhail, Khan; Tahir, Hussain; Ashfaque, H. Bokhari; Gulzar, Ali Khan

    2016-03-01

    In this note, we investigate conformal Killing vectors (CKVs) of locally rotationally symmetric (LRS) Bianchi type V spacetimes. Subject to some integrability conditions, CKVs up to implicit functions of (t,x) are obtained. Solving these integrability conditions in some particular cases, the CKVs are completely determined, obtaining a classification of LRS Bianchi type V spacetimes. The inheriting conformal Killing vectors of LRS Bianchi type V spacetimes are also discussed.

  11. Potency of killed plague vaccines prepared from avirulent Yersinia pestis*

    PubMed Central

    Williams, James E.; Altieri, Patricia L.; Berman, Sanford; Lowenthal, Joseph P.; Cavanaugh, Dan C.

    1980-01-01

    Killed plague vaccines prepared from avirulent strains A1122 and EV76S of Yersinia pestis were more effective in mouse potency tests than samples of Plague Vaccine, USP, prepared from killed Y. pestis of the virulent strain 195/P. Manufacture of vaccine from avirulent Y. pestis would obviate requirements for the large containment facilities that are currently needed for producing Plague Vaccine, USP. PMID:6975184

  12. Approximate Killing vectors on S{sup 2}

    SciTech Connect

    Cook, Gregory B.; Whiting, Bernard F.

    2007-08-15

    We present a new method for computing the best approximation to a Killing vector on closed 2-surfaces that are topologically S{sup 2}. When solutions of Killing's equation do not exist, this method is shown to yield results superior to those produced by existing methods. In addition, this method appears to provide a new tool for studying the horizon geometry of distorted black holes.

  13. 1. GENERAL VIEW OF HOG KILLING ROOM ON LEVEL 4; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GENERAL VIEW OF HOG KILLING ROOM ON LEVEL 4; LOOKING NORTHWEST; A PORTION OF THE SCALDING TANK IS VISIBLE AT EXTREME RIGHT, CENTER; CONCRETE PYLONS AT LOWER RIGHT SUPPORTED BY SCRAPING MACHINE; FINAL SCRAPING WAS DONE BY WORKERS STANDING ON ELEVATED PLATFORMS AT LEFT; BATHTUB-SHAPED CART NEAR CENTER OF PHOTO WAS USED TO TRANSPORT OFFAL TO RENDERING AREAS - Rath Packing Company, Hog Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  14. Killing forms on G2- and Spin-manifolds

    NASA Astrophysics Data System (ADS)

    Semmelmann, Uwe

    2006-09-01

    Killing forms on Riemannian manifolds are differential forms whose covariant derivative is totally skew-symmetric. We prove that on a compact manifold with holonomy G2 or Spin any Killing form has to be parallel. The main tool is a universal Weitzenböck formula. We show, how such a formula can be obtained for any given holonomy group and any representation defining a vector bundle.

  15. Atypical esthesioneuroblastoma invading oral cavity: a case report and review of the literature

    PubMed Central

    2014-01-01

    Esthesioneuroblastoma is an uncommon tumour of neuroectodermal origin. The authors describe a rare presentation of an atypical esthesioneuroblastoma invading oral cavity. The clinical presentation, aetiology, diagnosis, and management of this condition are discussed. The patient developed significant swelling in the right anterosuperior alveolar mucosa and had moderate tooth mobility. Conventional x-rays and computed tomography revealed a large osteolytic lesion, with imprecise limits. Histological findings along with immunohistochemical staining results and clinical features led to the diagnosis of high-grade esthesioneuroblastoma. Local recurrences and neck metastasis were detected. The rare oral findings produced delayed in diagnosis which may lead to a compromise in planning and execution of further radical management and thus a poor prognosis. Virtual slides The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1168853011139286. PMID:24443792

  16. Successful resection of thymoma directly invading the right atrium under cardiopulmonary bypass.

    PubMed

    De Giacomo, Tiziano; Patella, Miriam; Mazzesi, Giuseppe; Venuta, Federico

    2015-08-01

    We present the case of an invasive thymoma with severe compression of the right atrium, and infiltration of the atrial wall, causing a superior vena cava (SVC) syndrome. The tumour was resected under cardiopulmonary bypass en bloc with the atrial wall. A bovine pericardial patch was used for atrial reconstruction. We obtained a complete resection of the tumour and regression of symptoms, and, after 1 year of the follow-up, no signs of recurrence are evident. To our knowledge, this is the first case of thymoma directly invading the right atrium, without involvement of the SVC. In this setting, the aggressive surgical approach led to an immediate resolution of the symptoms and contributed to prolonged long-term survival. PMID:25293404

  17. Transferring automation for large-scale development and production of Invader SNP assays

    NASA Astrophysics Data System (ADS)

    Neri, Bruce P.; Ganske, R.; Isaczyszyn, W.; Beaty, Edward L.

    2000-03-01

    The Human Genome Project has led to the discovery of hundreds of thousands of single nucleotide polymorphisms (SNPs). SNPs can act as genetic markers to create high- density maps of the human genome for large-scale genetic analysis for evaluating links between genetic mutations and human diseases and for performing association studies. To create those maps, assays capable of detecting many different SNPs must be developed rapidly, as additional SNPs are discovered. When both the design of and the technology used in the assays can be partially or fully automated, the development process and the time to results can be accomplished quickly and efficiently. InvaderTM technology offers a highly sensitive signal amplification system that detects and quantifies mutations and SNPs from unamplified human genomic DNA in two sequential steps.

  18. What happens when Penelope comes?: An unusual retroelement invades a host species genome exploring different strategies.

    PubMed

    Evgen'ev, Michael B

    2013-03-01

    Transposable elements (TEs) are ubiquitous residents in eukaryotic genomes. They can cause dramatic changes in gene expression and lead to gross rearrangements of chromosome structure, providing the basis for rapid evolution. The virilis species group of Drosophila contains certain species that can be crossed under experimental conditions and their phylogeny is thoroughly investigated. We have shown that Drosophila virilis, the most primitive karyotypically and probably the ancestral species of the group, is in the process of colonization by a very unusual retroelement Penelope which apparently repeatedly invaded the species of the group in the past. However, the molecular mechanisms and evolutionary consequences of such invasions are poorly understood. In this commentary, we discuss the implications of our recent investigation into the response of the RNA silencing system to Penelope invasion of a new host genome which can be achieved in different ways. PMID:23914310

  19. Competitive helping increases with the size of biological markets and invades defection.

    PubMed

    Barclay, Pat

    2011-07-21

    Cooperation between unrelated individuals remains a puzzle in evolutionary biology. Recent work indicates that partner choice can select for high levels of helping. More generally, helping can be seen as but one strategy used to compete for partners within a broader biological market, yet giving within such markets has received little mathematical investigation. In the present model, individuals help others to attract attention from them and thus receive a larger share of any help actively or passively provided by those others. The evolutionarily stable level of helping increases with the size of the biological market and the degree of partner choice. Furthermore, if individuals passively produce some no-cost help to partners, competitive helping can then invade populations of non-helpers because helpers directly benefit from increasing their access to potential partners. This framework of competitive helping demonstrates how high helping can be achieved and why different populations may differ in helping levels. PMID:21550351

  20. Analysis of the theoretical model of drilling fluid invading into oceanic gas hydrates-bearing sediment

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Ning, F.; Jiang, G.; Wu, N.; Wu, D.

    2009-12-01

    Oceanic gas hydrate-bearing sediment is usually porous media, with the temperature and pressure closer to the curve of hydrate phase equilibrium than those in the permafrost region. In the case of near-balanced or over-balanced drilling through this sediment, the water-based drilling fluid used invades into this sediment, and hydrates decompose with heat transfer between drilling fluid and this sediment. During these processes, there are inevitably energy and mass exchanges between drilling fluid and the sediment, which will affect the logging response, borehole stability and reservoir evaluation. When drilling fluid invades into this sediment, solid and liquid phases of drilling fluid permeate into the wellbore and displace original fluids and solids, and water content of formation increases. With the temperature and pressure changing, gas hydrates in the sediment decompose into gas and water, and water content of formation further changes. When the filter cakes form, the invasion of drilling fluid is weakened. This process is accompanied by the heat and mass transfer within the range from wellbore to undisturbed area, including heat conduction of rock matrix, the convective heat transfer of fluids invaded, the heat absorbing of hydrate decomposition and the mass exchange between fluids invaded and the gas and water generated by hydrate decomposition. As a result, dynamic balance is built up and there are generally four different regions from wellbore to undisturbed area, i.e. filter cakes region, filter liquor region, water/free gas region, and water/free gas/hydrate region. According to the analysis on the invasion of drilling fuild into sediment, the whole invasion process can be described as an anisothermal and unstable displacement and diffusion process coupled with phase change. Refering to models of drilling fuilds invasion into normal oil and gas formation and natrual gas production from hydrate deposit by heating, the model of the invasion of drilling fluid into hydrate-bearing sediment has been preliminarily discussed based on kinetics of hydrate dissociation , with the assumption that hydrates were viewed as a portion of pore fluids and their decomposition was taken as a water and gas source without a uniform rate. A mathematical model was built up, and key parameters used for solving the kinetic equation of hydrate dissociation, such as the coefficient of effective porosity and permeability, absolute permeability, the synthetic specific heat and heat conductivity of hydrate-bearing sediment, are discussed. This model could be used to describe the dynamic process of drilling fluids invasion by coupling modified kinetic equation of heated hydrate decomposition into mass conservation equations, and also be used to study the evolution of pore water pressure, temperature, salinity, saturation of water/gas/hydrate with the depth of invasion and time. Key words: gas hydrates-bearing sediment, drilling fluid, hydrate dissociation, invasion process, model

  1. The Coffee Berry Borer (Hypothenemus hampei) Invades Hawaii: Preliminary Investigations on Trap Response and Alternate Hosts

    PubMed Central

    Messing, Russell H.

    2012-01-01

    In August 2010 the coffee berry borer, Hypothenemus hampei, was first reported to have invaded the Kona coffee growing region of Hawaii, posing a severe economic challenge to the fourth largest agricultural commodity in the State. Despite its long and widespread occurrence throughout the tropics as the most serious pest of coffee, there are still discrepancies in the literature regarding several basic aspects of berry borer biology relevant to its control. In Kona coffee plantations, we investigated the beetles’ response to several trap and lure formulations, and examined the occurrence of beetles in seeds of alternate host plants occurring adjacent to coffee farms. While traps were shown to capture significant numbers of beetles per day, and the occurrence of beetles in alternate hosts was quite rare, the unique situation of coffee culture in Hawaii will make this pest extremely challenging to manage in the Islands. PMID:26466620

  2. A new electromagnetic positioning method for tracking invaded medical devices using MARG sensors

    NASA Astrophysics Data System (ADS)

    Wang, Sen; Chen, Xiao-dong; Du, Cheng-yang; Wang, Yi; Yu, Dao-yin

    2013-08-01

    In clinical medicine, electromagnetic tracking (EMT) system, with its safely penetrating property for human tissue, has been an effective tracking and guiding method for invaded medical devices which are invisible inside a human body. However, traditional EMT system only implements magnetic methods to solve the complex 6-DOF equations and demands an ideal magnetic-field distribution model exited by electromagnetic coils or permanent magnet, resulting in poor anti-interference performance. This paper proposed a new method, combining EMT with the attitude convergence algorithm using MARG sensors. This fusion method reduces the information reliability on the external field, simplifies the complexity of magnetic analysis, and improves the robustness. Except for the accuracy testify experiment, we impose artificial interference to the DC voltage which excites external electromagnetic coils, and the tracking system could still maintain a high positioning stability.

  3. Aortic periannular abscess invading into the central fibrous body, mitral valve, and tricuspid valve.

    PubMed

    Oh, Hyun Kong; Kim, Nan Yeol; Kang, Min-Woong; Kang, Shin Kwang; Yu, Jae Hyeon; Lim, Seung Pyung; Choi, Jae Sung; Na, Myung Hoon

    2014-06-01

    A 61-year-old man was diagnosed with aortic stenoinsufficiency with periannular abscess, which involved the aortic root of noncoronary sinus (NCS) that invaded down to the central fibrous body, whole membranous septum, mitral valve (MV), and tricuspid valve (TV). The open complete debridement was executed from the aortic annulus at NCS down to the central fibrous body and annulus of the MV and the TV, followed by the left ventricular outflow tract reconstruction with implantation of a mechanical aortic valve by using a leaflet of the half-folded elliptical bovine pericardial patch. Another leaflet of this patch was used for the repair of the right atrial wall with a defect and the TV. PMID:25207228

  4. Invaded grassland communities have altered stability-maintenance mechanisms but equal stability compared to native communities.

    PubMed

    Wilsey, Brian J; Daneshgar, Pedram P; Hofmockel, Kirsten; Polley, H Wayne

    2014-01-01

    Theory predicts that stability should increase with diversity via several mechanisms. We tested predictions in a 5-year experiment that compared low-diversity exotic to high-diversity native plant mixtures under two irrigation treatments. The study included both wet and dry years. Variation in biomass across years (CV) was 50% lower in mixtures than monocultures of both native and exotic species. Growth among species was more asynchronous and overyielding values were greater during and after a drought in native than exotic mixtures. Mean-variance slopes indicated strong portfolio effects in both community types, but the intercept was higher for exotics than for natives, suggesting that exotics were inherently more variable than native species. However, this failed to result in higher CV's in exotic communities because species that heavily dominated plots tended to have lower than expected variance. Results indicate that diversity-stability mechanisms are altered in invaded systems compared to native ones they replaced. PMID:24325664

  5. Ability of Proteus mirabilis to invade human urothelial cells is coupled to motility and swarming differentiation.

    PubMed Central

    Allison, C; Coleman, N; Jones, P L; Hughes, C

    1992-01-01

    Proteus mirabilis causes serious kidney infections which can involve invasion of host urothelial cells. We present data showing that the ability to invade host urothelial cells is closely coupled to swarming, a form of cyclical multicellular behavior in which vegetative bacteria differentiate into hyperflagellated, filamentous swarm cells capable of coordinated and rapid population migration. Entry into the human urothelial cell line EJ/28 by P. mirabilis U6450 isolated at different stages throughout the swarming cycle was measured by the antibiotic protection assay method and confirmed by electron microscopy. Differentiated filaments entered urothelial cells within 30 min and were 15-fold more invasive (ca. 0.18% entry in 2 h) than an equivalent dry weight of vegetative cells isolated before differentiation, which attained only ca. 0.012% entry in the 2-h assay. The invasive ability of P. mirabilis was modulated in parallel with flagellin levels throughout two cycles of swarming. Septation and division of intracellular swarm cells produced between 50 and 300 vegetative bacteria per human cell, compared with 4 to 12 intracellular bacteria after incubation with vegetative cells. Transposon (Tn5) mutants of P. mirabilis with specific defects in motility and multicellular behavior were compared with the wild-type for the ability to invade. Mutants which lacked flagella (nonmotile nonswarming) were entirely noninvasive, and those which were motile but defective in swarm cell formation (motile nonswarming) were 25-fold less invasive than wild-type vegetative cells. Mutants with defects in the coordination of multicellular migration and the temporal control of consolidation (cyclical reversion of swarm cells to vegetative cells) were reduced ca. 3- to 12-fold in the ability to enter urothelial cells. In contrast, a nonhemolytic transposon mutant which swarmed normally retained over 80% of wild-type invasive ability. Swarm cells and early consolidation cells were at least 10-fold more cytolytic than vegetative cells as a result of their high-level production of hemolysin. Images PMID:1398984

  6. Grassland invaders and their mycorrhizal symbionts: a study across climate and invasion gradients

    PubMed Central

    Bunn, Rebecca A; Lekberg, Ylva; Gallagher, Christopher; Rosendahl, Søren; Ramsey, Philip W

    2014-01-01

    Controlled experiments show that arbuscular mycorrhizal fungi (AMF) can increase competitiveness of exotic plants, potentially increasing invasion success. We surveyed AMF abundance and community composition in Centaurea stoebe and Potentilla recta invasions in the western USA to assess whether patterns were consistent with mycorrhizal-mediated invasions. We asked whether (1) AMF abundance and community composition differ between native and exotic forbs, (2) associations between native plants and AMF shift with invading exotic plants, and (3) AMF abundance and/or community composition differ in areas where exotic plants are highly invasive and in areas where they are not. We collected soil and roots from invaded and native forb communities along invasion gradients and in regions with different invasion densities. We used AMF root colonization as a measure of AMF abundance and characterized AMF communities in roots using 454-sequencing of the LSU-rDNA region. All plants were highly colonized (>60%), but exotic forbs tended to be more colonized than natives (P < 0.001). We identified 30 AMF operational taxonomic units (OTUs) across sites, and community composition was best predicted by abiotic factors (soil texture, pH). Two OTUs in the genera Glomus and Rhizophagus dominated in most communities, and their dominance increased with invasion density (r = 0.57, P = 0.010), while overall OTU richness decreased with invasion density (r = −0.61, P = 0.006). Samples along P. recta invasion gradients revealed small and reciprocal shifts in AMF communities with >45% fungal OTUs shared between neighboring native and P. recta plants. Overall, we observed significant, but modest, differences in AMF colonization and communities between co-occurring exotic and native forbs and among exotic forbs across regions that differ in invasion pressure. While experimental manipulations are required to assess functional consequences, the observed patterns are not consistent with those expected from strong mycorrhizal-mediated invasions. PMID:24683461

  7. Oceanographic Conditions Limit the Spread of a Marine Invader along Southern African Shores.

    PubMed

    Assis, Jorge; Zupan, Mirta; Nicastro, Katy R; Zardi, Gerardo I; McQuaid, Christopher D; Serrão, Ester A

    2015-01-01

    Invasive species can affect the function and structure of natural ecological communities, hence understanding and predicting their potential for spreading is a major ecological challenge. Once established in a new region, the spread of invasive species is largely controlled by their dispersal capacity, local environmental conditions and species interactions. The mussel Mytilus galloprovincialis is native to the Mediterranean and is the most successful marine invader in southern Africa. Its distribution there has expanded rapidly and extensively since the 1970s, however, over the last decade its spread has ceased. In this study, we coupled broad scale field surveys, Ecological Niche Modelling (ENM) and Lagrangian Particle Simulations (LPS) to assess the current invaded distribution of M. galloprovincialis in southern Africa and to evaluate what prevents further spread of this species. Results showed that all environmentally suitable habitats in southern Africa have been occupied by the species. This includes rocky shores between Rocky Point in Namibia and East London in South Africa (approx. 2800 km) and these limits coincide with the steep transitions between cool-temperate and subtropical-warmer climates, on both west and southeast African coasts. On the west coast, simulations of drifting larvae almost entirely followed the northward and offshore direction of the Benguela current, creating a clear dispersal barrier by advecting larvae away from the coast. On the southeast coast, nearshore currents give larvae the potential to move eastwards, against the prevalent Agulhas current and beyond the present distributional limit, however environmental conditions prevent the establishment of the species. The transition between the cooler and warmer water regimes is therefore the main factor limiting the northern spread on the southeast coast; however, biotic interactions with native fauna may also play an important role. PMID:26114766

  8. Linking Native and Invader Traits Explains Native Spider Population Responses to Plant Invasion

    PubMed Central

    Emlen, Douglas J.; Pearson, Dean E.

    2016-01-01

    Theoretically, the functional traits of native species should determine how natives respond to invader-driven changes. To explore this idea, we simulated a large-scale plant invasion using dead spotted knapweed (Centaurea stoebe) stems to determine if native spiders’ web-building behaviors could explain differences in spider population responses to structural changes arising from C. stoebe invasion. After two years, irregular web-spiders were >30 times more abundant and orb weavers were >23 times more abundant on simulated invasion plots compared to controls. Additionally, irregular web-spiders on simulated invasion plots built webs that were 4.4 times larger and 5.0 times more likely to capture prey, leading to >2-fold increases in recruitment. Orb-weavers showed no differences in web size or prey captures between treatments. Web-spider responses to simulated invasion mimicked patterns following natural invasions, confirming that C. stoebe’s architecture is likely the primary attribute driving native spider responses to these invasions. Differences in spider responses were attributable to differences in web construction behaviors relative to historic web substrate constraints. Orb-weavers in this system constructed webs between multiple plants, so they were limited by the overall quantity of native substrates but not by the architecture of individual native plant species. Irregular web-spiders built their webs within individual plants and were greatly constrained by the diminutive architecture of native plant substrates, so they were limited both by quantity and quality of native substrates. Evaluating native species traits in the context of invader-driven change can explain invasion outcomes and help to identify factors limiting native populations. PMID:27082240

  9. The Anomalous Diffusion of a Tumor Invading with Different Surrounding Tissues

    PubMed Central

    Jiang, Chongming; Cui, Chunyan; Li, Li; Shao, Yuanzhi

    2014-01-01

    We simulated the invasion of a proliferating, diffusing tumor within different surrounding tissue conditions using a hybrid mathematical model. The in silico invasion of a tumor was addressed systematically for the first time within the framework of a generalized diffusion theory. Our results reveal that a tumor not only migrates using typical Fickian diffusion, but also migrates more generally using subdiffusion, superdiffusion, and even ballistic diffusion, with increasing mobility of the tumor cell when haptotaxis and chemotaxis toward the host tissue surrounding the proliferative tumor are involved. Five functional terms were included in the hybrid model and their effects on a tumor's invasion were investigated quantitatively: haptotaxis toward the extracellular matrix tissue that is degraded by matrix metalloproteinases; chemotaxis toward nutrients; cell-cell adhesion; the proliferation of the tumor; and the immune response toward the tumor. Haptotaxis and chemotaxis, which are initiated by extracellular matrix and nutrient supply (i.e., glucose) respectively, as well as cell-cell adhesions all drastically affect a tumor's diffusion mode when a tumor invades its surrounding host tissue and proliferates. We verified the in silico invasive behavior of a tumor by analyzing experimental data gathered from the in vitro culturing of different tumor cells and clinical imaging observations that used the same approach as was used to process the simulation data. The different migration modes of a tumor suggested by the simulations generally conform to the results observed in cell cultures and in clinical imaging. Our study not only discloses some migration modes of a tumor that proliferates and invades under different host tissues conditions, but also provides a heuristic method to characterize the invasion of a tumor in clinical medical imaging analysis. PMID:25310134

  10. Oceanographic Conditions Limit the Spread of a Marine Invader along Southern African Shores

    PubMed Central

    Nicastro, Katy R.; Zardi, Gerardo I.; McQuaid, Christopher D.; Serrão, Ester A.

    2015-01-01

    Invasive species can affect the function and structure of natural ecological communities, hence understanding and predicting their potential for spreading is a major ecological challenge. Once established in a new region, the spread of invasive species is largely controlled by their dispersal capacity, local environmental conditions and species interactions. The mussel Mytilus galloprovincialis is native to the Mediterranean and is the most successful marine invader in southern Africa. Its distribution there has expanded rapidly and extensively since the 1970s, however, over the last decade its spread has ceased. In this study, we coupled broad scale field surveys, Ecological Niche Modelling (ENM) and Lagrangian Particle Simulations (LPS) to assess the current invaded distribution of M. galloprovincialis in southern Africa and to evaluate what prevents further spread of this species. Results showed that all environmentally suitable habitats in southern Africa have been occupied by the species. This includes rocky shores between Rocky Point in Namibia and East London in South Africa (approx. 2800 km) and these limits coincide with the steep transitions between cool-temperate and subtropical-warmer climates, on both west and southeast African coasts. On the west coast, simulations of drifting larvae almost entirely followed the northward and offshore direction of the Benguela current, creating a clear dispersal barrier by advecting larvae away from the coast. On the southeast coast, nearshore currents give larvae the potential to move eastwards, against the prevalent Agulhas current and beyond the present distributional limit, however environmental conditions prevent the establishment of the species. The transition between the cooler and warmer water regimes is therefore the main factor limiting the northern spread on the southeast coast; however, biotic interactions with native fauna may also play an important role. PMID:26114766

  11. Linking Native and Invader Traits Explains Native Spider Population Responses to Plant Invasion.

    PubMed

    Smith, Jennifer N; Emlen, Douglas J; Pearson, Dean E

    2016-01-01

    Theoretically, the functional traits of native species should determine how natives respond to invader-driven changes. To explore this idea, we simulated a large-scale plant invasion using dead spotted knapweed (Centaurea stoebe) stems to determine if native spiders' web-building behaviors could explain differences in spider population responses to structural changes arising from C. stoebe invasion. After two years, irregular web-spiders were >30 times more abundant and orb weavers were >23 times more abundant on simulated invasion plots compared to controls. Additionally, irregular web-spiders on simulated invasion plots built webs that were 4.4 times larger and 5.0 times more likely to capture prey, leading to >2-fold increases in recruitment. Orb-weavers showed no differences in web size or prey captures between treatments. Web-spider responses to simulated invasion mimicked patterns following natural invasions, confirming that C. stoebe's architecture is likely the primary attribute driving native spider responses to these invasions. Differences in spider responses were attributable to differences in web construction behaviors relative to historic web substrate constraints. Orb-weavers in this system constructed webs between multiple plants, so they were limited by the overall quantity of native substrates but not by the architecture of individual native plant species. Irregular web-spiders built their webs within individual plants and were greatly constrained by the diminutive architecture of native plant substrates, so they were limited both by quantity and quality of native substrates. Evaluating native species traits in the context of invader-driven change can explain invasion outcomes and help to identify factors limiting native populations. PMID:27082240

  12. Differences in ecological structure, function, and native species abundance between native and invaded Hawaiian streams.

    PubMed

    Holitzki, Tara M; MacKenzie, Richard A; Wiegner, Tracy N; McDermid, Karla J

    2013-09-01

    Poeciliids, one of the most invasive species worldwide, are found on almost every continent and have been identified as an "invasive species of concern" in the United States, New Zealand, and Australia. Despite their global prevalence, few studies have quantified their impacts on tropical stream ecosystem structure, function, and biodiversity. Utilizing Hawaiian streams as model ecosystems, we documented how ecological structure, function, and native species abundance differed between poeciliid-free and poeciliid-invaded tropical streams. Stream nutrient yields, benthic biofilm biomass, densities of macroinvertebrates and fish, and community structures of benthic algae, macroinvertebrates, and fish were compared between streams with and without established poeciliid populations on the island of Hawai'i, Hawaii, USA. Sum nitrate (sigmaNO3(-) = NO3(-) + NO2(-)), total nitrogen, and total organic carbon yields were eight times, six times, and five times higher, respectively, in poeciliid streams than in poeciliid-free streams. Benthic biofilm ash-free dry mass was 1.5x higher in poeciliid streams than in poeciliid-free streams. Percentage contributions of chironomids and hydroptilid caddisflies to macroinvertebrate densities were lower in poeciliid streams compared to poeciliid-free streams, while percentage contributions of Cheumatopsyche analis caddisflies, Dugesia sp. flatworms, and oligochaetes were higher. Additionally, mean densities of native gobies were two times lower in poeciliid streams than in poeciliid-free ones, with poeciliid densities being approximately eight times higher than native fish densities. Our results, coupled with the wide distribution of invasive poeciliids across Hawaii and elsewhere in the tropics, suggest that poeciliids may negatively impact the ecosystem structure, function, and native species abundance of tropical streams they invade. This underscores the need for increased public awareness to prevent future introductions and for developing and implementing effective eradication and restoration strategies. PMID:24147409

  13. A generic risk-based surveying method for invading plant pathogens.

    PubMed

    Parnell, S; Gottwald, T R; Riley, T; van den Bosch, F

    2014-06-01

    Invasive plant pathogens are increasing with international trade and travel, with damaging environmental and economic consequences. Recent examples include tree diseases such as sudden oak death in the Western United States and ash dieback in Europe. To control an invading pathogen it is crucial that newly infected sites are quickly detected so that measures can be implemented to control the epidemic. However, since sampling resources are often limited, not all locations can be inspected and locations must be prioritized for surveying. Existing approaches to achieve this are often species specific and rely on detailed data collection and parameterization, which is difficult, especially when new arrivals are unanticipated. Consequently regulatory sampling responses are often ad hoc and developed without due consideration of epidemiology, leading to the suboptimal deployment of expensive sampling resources. We introduce a flexible risk-based sampling method that is pathogen generic and enables available information to be utilized to develop epidemiologically informed sampling programs for virtually any biologically relevant plant pathogen. By targeting risk we aim to inform sampling schemes that identify high-impact locations that can be subsequently treated in order to reduce inoculum in the landscape. This "damage limitation" is often the initial management objective following the first discovery of a new invader. Risk at each location is determined by the product of the basic reproductive number (R0), as a measure of local epidemic size, and the probability of infection. We illustrate how the risk estimates can be used to prioritize a survey by weighting a random sample so that the highest-risk locations have the highest probability of selection. We demonstrate and test the method using a high-quality spatially and temporally resolved data set on Huanglongbing disease (HLB) in Florida, USA. We show that even when available epidemiological information is relatively minimal, the method has strong predictive value and can result in highly effective targeted surveying plans. PMID:24988776

  14. Rates of CTL killing in persistent viral infection in vivo.

    PubMed

    Elemans, Marjet; Florins, Arnaud; Willems, Luc; Asquith, Becca

    2014-04-01

    The CD8+ cytotoxic T lymphocyte (CTL) response is an important defence against viral invasion. Although CTL-mediated cytotoxicity has been widely studied for many years, the rate at which virus-infected cells are killed in vivo by the CTL response is poorly understood. To date the rate of CTL killing in vivo has been estimated for three virus infections but the estimates differ considerably, and killing of HIV-1-infected cells was unexpectedly low. This raises questions about the typical anti-viral capability of CTL and whether CTL killing is abnormally low in HIV-1. We estimated the rate of killing of infected cells by CD8+ T cells in two distinct persistent virus infections: sheep infected with Bovine Leukemia Virus (BLV) and humans infected with Human T Lymphotropic Virus type 1 (HTLV-1) which together with existing data allows us to study a total of five viruses in parallel. Although both BLV and HTLV-1 infection are characterised by large expansions of chronically activated CTL with immediate effector function ex vivo and no evidence of overt immune suppression, our estimates are at the lower end of the reported range. This enables us to put current estimates into perspective and shows that CTL killing of HIV-infected cells may not be atypically low. The estimates at the higher end of the range are obtained in more manipulated systems and may thus represent the potential rather than the realised CTL efficiency. PMID:24699260

  15. Rates of CTL Killing in Persistent Viral Infection In Vivo

    PubMed Central

    Elemans, Marjet; Florins, Arnaud; Willems, Luc; Asquith, Becca

    2014-01-01

    The CD8+ cytotoxic T lymphocyte (CTL) response is an important defence against viral invasion. Although CTL-mediated cytotoxicity has been widely studied for many years, the rate at which virus-infected cells are killed in vivo by the CTL response is poorly understood. To date the rate of CTL killing in vivo has been estimated for three virus infections but the estimates differ considerably, and killing of HIV-1-infected cells was unexpectedly low. This raises questions about the typical anti-viral capability of CTL and whether CTL killing is abnormally low in HIV-1. We estimated the rate of killing of infected cells by CD8+ T cells in two distinct persistent virus infections: sheep infected with Bovine Leukemia Virus (BLV) and humans infected with Human T Lymphotropic Virus type 1 (HTLV-1) which together with existing data allows us to study a total of five viruses in parallel. Although both BLV and HTLV-1 infection are characterised by large expansions of chronically activated CTL with immediate effector function ex vivo and no evidence of overt immune suppression, our estimates are at the lower end of the reported range. This enables us to put current estimates into perspective and shows that CTL killing of HIV-infected cells may not be atypically low. The estimates at the higher end of the range are obtained in more manipulated systems and may thus represent the potential rather than the realised CTL efficiency. PMID:24699260

  16. On conformal Killing 2-form of the electromagnetic field

    NASA Astrophysics Data System (ADS)

    Stepanov, S. E.

    2000-04-01

    Let D: C∞ΛpM→ C∞( T*M⊗ ΛpM) be the first order linear differential operator on an n-dimensional (1≤ p≤ n-1) pseudo-Riemannian manifold ( M, g). We have by the representation theory of orthogonal group, that the tangent bundle of this operation decomposes into the orthogonal and irreducible sum of forms of degree p+1 (which gives the exterior differential d), the forms of degree p-1 (defining the codifferential d *) and the trace-free part of the partial symmetrization (the corresponding first order operator is denoted by D). The general forms in the kernel of D are closely related to conformal Killing vector fields, called conformal Killing p-forms, while those in kernel of d are called closed conformal Killing p-forms or, according to another terminology, planar p-forms. In particular an arbitrary planar 1-form ω is dual (by g) to the special concircular vector field ξ. We consider some local properties for the closed conformal Killing p-forms. As an application we present examples of decomposition into irreducible components for the electromagnetic field 2-form ω and its covariant derivative in four-dimensional space-time. In particular, we prove that the energy-momentum tensor T of the electromagnetic field is a symmetric conformal Killing tensor if the electromagnetic field 2-form ω is a conformal Killing form.

  17. Extended resection of non-small cell lung cancer invading the left atrium, is it worth the risk?

    PubMed

    Galvaing, Geraud; Chadeyras, Jean Baptiste; Merle, Patrick; Tardy, Marie M; Naamee, Adel; Bailly, Patrick; Filaire, Marc

    2015-12-01

    Only few reports of surgical approach to T4 lung carcinoma invading the heart have been reported in the medical literature. It is also controversial if such cancer should be treated by surgery. The aim of this review is to assess the current risk/benefit ratio of the surgical management of non-small cell lung cancer (NSCLC) invading the left atrium, especially in the light of a multidisciplinary approach. We also expose our surgical experience and the procedure we have developed in order to increase our rate of complete resection as this criterion appears to be mandatory as well as patients' nodal status in order to increase life expectancy. PMID:26730755

  18. Complete nitrification by a single microorganism

    PubMed Central

    van Kessel, Maartje A.H.J.; Speth, Daan R.; Albertsen, Mads; Nielsen, Per H.; Op den Camp, Huub J.M.; Kartal, Boran; Jetten, Mike S.M.; Lücker, Sebastian

    2016-01-01

    Summary Nitrification is a two-step process where ammonia is considered to first be oxidized to nitrite by ammonia-oxidizing bacteria (AOB) and/or archaea (AOA), and subsequently to nitrate by nitrite-oxidizing bacteria (NOB). Described by Winogradsky already in 18901, this division of labour between the two functional groups is a generally accepted characteristic of the biogeochemical nitrogen cycle2. Complete oxidation of ammonia to nitrate in one organism (complete ammonia oxidation; comammox) is energetically feasible and it was postulated that this process could occur under conditions selecting for species with lower growth-rates but higher growth-yields than canonical ammonia-oxidizing microorganisms3. Still, organisms catalysing this process have not yet been discovered. Here, we report the enrichment and initial characterization of two Nitrospira species that encode all enzymes necessary for ammonia oxidation via nitrite to nitrate in their genomes, and indeed completely oxidize ammonium to nitrate to conserve energy. Their ammonia monooxygenase (AMO) enzymes are phylogenetically distinct from currently identified AMOs, rendering recent acquisition by horizontal gene transfer from known ammonia-oxidizing microorganisms unlikely. We also found highly similar amoA sequences (encoding the AMO subunit A) in public sequence databases, which were apparently misclassified as methane monooxygenases. This recognition of a novel amoA sequence group will lead to an improved understanding on the environmental abundance and distribution of ammonia-oxidizing microorganisms. Furthermore, the discovery of the long-sought-after comammox process will change our perception of the nitrogen cycle. PMID:26610025

  19. Extremophilic microorganisms as candidates for extraterrestrial life

    NASA Astrophysics Data System (ADS)

    Seckbach, Joseph; Oren, Aharon

    2000-12-01

    Microbial life is found all over the globe. Diverse communities are even found in such places in which extreme conditions with respect of temperature, salinity, pH, and pressure prevail. Many of these environments were until recently considered too harsh to harbor microbial life. The micro-organisms adapted to an existence at the edge of life are termed extremophiles. They include members of the Prokaryotes (domains Archaea and Bacteria) and the Eukarya, including algae and protozoa. Extremophilic microbes thrive at low and high temperatures -- from subzero levels to above the boiling point of water, at both sides of the pH scale -- in acidic as well as in alkaline media, in hypersaline environments with salt concentrations of up to saturation, at high pressure, both in the deep sea and in the terrestrial deep subsurface where they are exposed to pressures of hundreds of atmospheres, and in other extreme conditions. In many cases they tolerate combinations of more than one environmental stress factor. Some of the extremophiles may be considered as 'living fossils' since their environment resembles the conditions that may have existed during the time life arose on Earth, more than 3.5 billion years ago. In view of these properties the extremophilic micro-organisms may be considered as model organisms when exploring the possibilities of the existence of extraterrestrial life. For example, the microbes discovered in ice cores recovered from the depth of the Lake Vostok in Antarctica may serve as a model simulating conditions prevailing in the permafrost subsurface of Mars or Jupiter's moon Europa. Microbial life in the Dead Sea or in Great Salt Lake may resemble halophilic life forms that may exist elsewhere in the universe, adapted to life at low water activities. Likewise, hyperthermophilic micro-organisms present on Earth in hot springs, hydrothermal vents and other sites heated by volcanic activity in terrestrial or marine areas, may resemble life forms that may exist on hot planets such as Venus.

  20. Phylogenetic conservatism of functional traits in microorganisms.

    PubMed

    Martiny, Adam C; Treseder, Kathleen; Pusch, Gordon

    2013-04-01

    A central question in biology is how biodiversity influences ecosystem functioning. Underlying this is the relationship between organismal phylogeny and the presence of specific functional traits. The relationship is complicated by gene loss and convergent evolution, resulting in the polyphyletic distribution of many traits. In microorganisms, lateral gene transfer can further distort the linkage between phylogeny and the presence of specific functional traits. To identify the phylogenetic conservation of specific traits in microorganisms, we developed a new phylogenetic metric-consenTRAIT-to estimate the clade depth where organisms share a trait. We then analyzed the distribution of 89 functional traits across a broad range of Bacteria and Archaea using genotypic and phenotypic data. A total of 93% of the traits were significantly non-randomly distributed, which suggested that vertical inheritance was generally important for the phylogenetic dispersion of functional traits in microorganisms. Further, traits in microbes were associated with a continuum of trait depths (τD), ranging from a few deep to many shallow clades (average τD: 0.101-0.0011 rRNA sequence dissimilarity). Next, we demonstrated that the dispersion and the depth of clades that contain a trait is correlated with the trait's complexity. Specifically, complex traits encoded by many genes like photosynthesis and methanogenesis were found in a few deep clusters, whereas the ability to use simple carbon substrates was highly phylogenetically dispersed. On the basis of these results, we propose a framework for predicting the phylogenetic conservatism of functional traits depending on the complexity of the trait. This framework enables predicting how variation in microbial composition may affect microbially-mediated ecosystem processes as well as linking phylogenetic and trait-based patterns of biogeography. PMID:23235290

  1. Screening of biosurfactants from cloud microorganisms

    NASA Astrophysics Data System (ADS)

    Sancelme, Martine; Canet, Isabelle; Traikia, Mounir; Uhliarikova, Yveta; Capek, Peter; Matulova, Maria; Delort, Anne-Marie; Amato, Pierre

    2015-04-01

    The formation of cloud droplets from aerosol particles in the atmosphere is still not well understood and a main source of uncertainties in the climate budget today. One of the principal parameters in these processes is the surface tension of atmospheric particles, which can be strongly affected by trace compounds called surfactants. Within a project devoted to bring information on atmospheric surfactants and their effects on cloud droplet formation, we focused on surfactants produced by microorganisms present in atmospheric waters. From our unique collection of microorganisms, isolated from cloud water collected at the Puy-de-Dôme (France),1 we undertook a screening of this bank for biosurfactant producers. After extraction of the supernatants of the pure cultures, surface tension of crude extracts was determined by the hanging drop technique. Results showed that a wide variety of microorganisms are able to produce biosurfactants, some of them exhibiting strong surfactant properties as the resulting tension surface decreases to values less then 35 mN.m-1. Preliminary analytical characterization of biosurfactants, obtained after isolation from overproducing cultures of Rhodococcus sp. and Pseudomonas sp., allowed us to identify them as belonging to two main classes, namely glycolipids and glycopeptides. 1. Vaïtilingom, M.; Attard, E.; Gaiani, N.; Sancelme, M.; Deguillaume, L.; Flossmann, A. I.; Amato, P.; Delort, A. M. Long-term features of cloud microbiology at the puy de Dôme (France). Atmos. Environ. 2012, 56, 88-100. Acknowledgements: This work is supported by the French-USA ANR SONATA program and the French-Slovakia programs Stefanik and CNRS exchange.

  2. Symmetry operators of Killing spinors and superalgebras in AdS5

    NASA Astrophysics Data System (ADS)

    Ertem, Ümit

    2016-04-01

    We construct the first-order symmetry operators of Killing spinor equation in terms of odd Killing-Yano forms. By modifying the Schouten-Nijenhuis bracket of Killing-Yano forms, we show that the symmetry operators of Killing spinors close into an algebra in AdS5 spacetime. Since the symmetry operator algebra of Killing spinors corresponds to a Jacobi identity in extended Killing superalgebras, we investigate the possible extensions of Killing superalgebras to include higher-degree Killing-Yano forms. We found that there is a superalgebra extension but no Lie superalgebra extension of the Killing superalgebra constructed out of Killing spinors and odd Killing-Yano forms in AdS5 background.

  3. Microorganisms and biomolecules in space hard environment

    NASA Technical Reports Server (NTRS)

    Horneck, G.

    1981-01-01

    Microorganisms and biomolecules exposed to space vacuum and to different intensities of selected wavelengths of solar ultraviolet radiation is studied. The influence of these factors, applied singly or simultaneously, on the integrity of microbial systems and biomolecules is measured. Specifically, this experiment will study in Bacillus subtilis spores (1) disturbances in subsequent germination, outgrowth, and colony formation; (2) photochemical reactions of the DNA and protein in vivo and in vitro and their role in biological injury; and (3) the efficiency of repair processes in these events.

  4. Endolithic Microorganisms in the Antarctic Cold Desert

    NASA Astrophysics Data System (ADS)

    Imre Friedmann, E.

    1982-02-01

    In the frigid desert of the Antarctic dry valleys there are no visible life forms on the surface of the soil or rocks. Yet in certain rock types a narrow subsurface zone has a favorable microclimate and is colonized by microorganisms. Dominant are lichens of unusual organization. They survive not by physiological adaptation to lower temperatures, but by changing their mode of growth, being able to grow between the crystals of porous rocks. Their activity results in mobilization of iron compounds and in rock weathering with a characteristic pattern of exfoliation. This simple ecosystem lacks both higher consumers and predators.

  5. Resistance of soil microorganisms to starvation.

    NASA Technical Reports Server (NTRS)

    Chen, M.; Alexander, M.

    1972-01-01

    Most groups of soil microorganisms died when exposed to prolonged starvation in a carbon-free solution, but the relative abundance of Bacillus and actinomycetes increased with time. Certain nonspore-forming bacteria also persisted. The ability of individual soil isolates to endure starvation in solution was not correlated with their glycogen content or rate of endogenous respiration. However, cells of the resistant populations were rich in poly-beta-hydroxybutyrate, whereas the starvation-susceptible bacteria generally contained little of this substance. Poly-beta-hydroxybutyrate was used rapidly in cells deprived of exogenous sources of carbon.

  6. Temperature response of Antarctic cryptoendolithic photosynthetic microorganisms

    NASA Technical Reports Server (NTRS)

    Ocampo-Friedmann, R.; Meyer, M. A.; Chen, M.; Friedmann, E. I.

    1988-01-01

    Growth responses to temperatures between 12.5 [degrees] C and 25 degrees C were determined for five photosynthetic microorganisms isolated from the Ross Desert cryptoendolithic community. Among eukaryotic algae, two strains of Trebouxia sp. have an upper temperature limit of 20 degrees C, and two strains of Hemichloris antarctica of 25 degrees C. The cyanobacterium Chroococcidiopsis sp., in contrast, grows at temperatures above 25 degrees C. These and earlier studies suggest that the eukaryotic algae of the Antarctic cryptoendolithic community have an upper temperature limit near 25 degrees C.

  7. COMPOSTING: STABILIZATION, DEWATERING, VOLUME REDUCTION, AND PATHOGEN KILL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aerobic composting is the biological oxidative decomposition of organic materials by successive communities of microorganisms under different temperature regimes which produces a humified end-product. Composting reduces moisture content of organic byproducts. Thermophilic temperatures attained dur...

  8. Rapid evolution of novel traits in microorganisms.

    PubMed

    Selifonova, O; Valle, F; Schellenberger, V

    2001-08-01

    The use of natural microorganisms in biotransformations is frequently constrained by their limited tolerance to the high concentrations of metabolites and solvents required for effective industrial production. In many cases, more robust strains have to be generated by random mutagenesis and selection. This process of directed evolution can be accelerated in mutator strains, which carry defects in one or more of their DNA repair genes. However, in order to use mutator strains, it is essential to restore the normal low mutation rate of the selected organisms immediately after selection to prevent the accumulation of undesirable spontaneous mutations. To enable this process, we constructed temperature-sensitive plasmids that temporarily increase the mutation frequency of their hosts by 20- to 4,000-fold. Under appropriate selection pressure, microorganisms transformed with mutator plasmids can be quickly evolved to exhibit new, complex traits. By using this approach, we were able to increase the tolerance of three bacterial strains to dimethylformamide by 10 to 20 g/liter during only two subsequent transfers. Subsequently, the evolved strains were returned to their normal low mutation rate by curing the cells of the mutator plasmids. Our results demonstrate a new and efficient method for rapid strain improvement based on in vivo mutagenesis. PMID:11472942

  9. Diversity of Thermophilic Microorganisms within Hawaiian Fumaroles

    NASA Astrophysics Data System (ADS)

    Ackerman, C. A.; Anderson, S.; Anderson, C.

    2007-12-01

    Fumaroles provide heat and moisture characteristic of an environment suitable for thermophilic microorganisms. On the Island of Hawaii, fumaroles are scattered across the southeastern portion of the island as a result of the volcanic activity from Kilauea Crater and Pu'u' O'o vent. We used metagenomics to detect 16S rDNA from archaeal and bacterial thermophilic microorganisms indicating their presence in Hawaiian fumaroles. The fumaroles sampled exist along elevation and precipitation gradients; varying from sea level to 4,012ft and annual rainfall from less than 20in to greater than 80in. To determine the effects of environmental gradients (including temperature, pH, elevation, and precipitation) on microbial diversity within and among fumaroles, we obtained 22 samples from 7 fumaroles over a three-day period in February of 2007. Temperature variations within individual fumaroles vary from 2.3oC to 35oC and the pH variances that range from 0.4 to 2.0. Temperatures of the different fumaroles range from 29.9oC to greater than 105oC, with pH values that vary from 2.55 to 6.93. Further data on the microbial diversity within fumaroles and among fumaroles will be determined once the sequencing of the microbial 16S rDNA regions is completed. We are currently assembling and sequencing clone libraries of bacterial and archaeal 16S rDNA fragments from fumaroles.

  10. Microorganisms capable of metabolizing the herbicide metolachlor.

    PubMed Central

    Saxena, A; Zhang, R W; Bollag, J M

    1987-01-01

    We screened several strains of microorganisms and microbial populations for their ability to mineralize or transform the herbicide metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)-acetami de] because such cultures would potentially be useful in the cleanup of contaminated sites. Although we used various inocula and enrichment culture techniques, we were not able to isolate microorganisms that could mineralize metolachlor. However, strains of Bacillus circulans, Bacillus megaterium, Fusarium sp., Mucor racemosus, and an actinomycete were found to transform metolachlor. Several metabolites could be determined with high-performance liquid chromatography. The tolerance of the strains to high concentrations of metolachlor was also evaluated for the usefulness of the strains for decontamination. Tolerance of the actinomycete to metolachlor concentrations over 200 ppm (200 micrograms/ml) was low and could not be increased by doubling the sucrose concentration in the growth medium or by using a large biomass as inoculum. However, a Fusarium sp. could grow and transform metolachlor up to a concentration of 300 ppm. PMID:3105457

  11. Microorganisms Resistant to Free-Living Amoebae

    PubMed Central

    Greub, Gilbert; Raoult, Didier

    2004-01-01

    Free-living amoebae feed on bacteria, fungi, and algae. However, some microorganisms have evolved to become resistant to these protists. These amoeba-resistant microorganisms include established pathogens, such as Cryptococcus neoformans, Legionella spp., Chlamydophila pneumoniae, Mycobacterium avium, Listeria monocytogenes, Pseudomonas aeruginosa, and Francisella tularensis, and emerging pathogens, such as Bosea spp., Simkania negevensis, Parachlamydia acanthamoebae, and Legionella-like amoebal pathogens. Some of these amoeba-resistant bacteria (ARB) are lytic for their amoebal host, while others are considered endosymbionts, since a stable host-parasite ratio is maintained. Free-living amoebae represent an important reservoir of ARB and may, while encysted, protect the internalized bacteria from chlorine and other biocides. Free-living amoebae may act as a Trojan horse, bringing hidden ARB within the human “Troy,” and may produce vesicles filled with ARB, increasing their transmission potential. Free-living amoebae may also play a role in the selection of virulence traits and in adaptation to survival in macrophages. Thus, intra-amoebal growth was found to enhance virulence, and similar mechanisms seem to be implicated in the survival of ARB in response to both amoebae and macrophages. Moreover, free-living amoebae represent a useful tool for the culture of some intracellular bacteria and new bacterial species that might be potential emerging pathogens. PMID:15084508

  12. Bioremediation of trinitrotolulene by a ruminal microorganism

    SciTech Connect

    Lee, Taejin; Williamson, K.J.; Craig, A.M.

    1995-10-01

    2,4,6-trinitrotoluene (TNT) has been widely used for the production of explosives because of its low boiling point, high stability, low impact sensitivity, and safe manufacture. More than 1,100 military facilities, each potentially contaminated with munitions waste, are expected to require treatment of more than one million cubic yards of contaminated soils. The cost associated with remediation of these sites has been estimated to be in excess of $1.5 billion. Recently, researchers have studied ruminal microorganisms in relation to their ability to degrade xenobiotic compounds. Many of these organisms are strict anaerobes with optimal redox potentials as low as -420 mV. Ruminal organisms have been shown capable of destroying some pesticides, such as parathion, p-nitrophenol, and biphenyl-type compounds; thiono isomers, and nitrogen-containing heterocyclic plant toxins such as the pyrrolizidine alkaloids. Many of these compounds have structures similar to TNT. A TNT-degrading ruminal microorganism has been isolated from goat rumen fluid with successive enrichments on triaminotoluene (TAT) and TNT. The isolate, designated G.8, utilizes nitrate and lactate as the primary energy source. G.8 was able to tolerate and metabolite levels of TNT up to the saturation point of 125 mg/l.

  13. Sterilization of Microorganisms by Ozone and Ultrasound

    NASA Astrophysics Data System (ADS)

    Krasnyj, V. V.; Klosovskij, A. V.; Panasko, T. A.; Shvets, O. M.; Semenova, O. T.; Taran, V. S.; Tereshin, V. I.

    2008-03-01

    The results of recent experimental methods of sterilization of microorganisms with the use of ozone and ultrasound are presented. The main aim was to optimize the process of sterilization in water solution taking into account the ozone concentration, the power of ultrasonic emitter and the temperature of water. In the present work, the ultrasonic cavitation with simultaneous ozone generation has been used. The high ozone concentration in water solution was achieved by two-barrier glow discharge generated at atmospheric pressure and a cooling thermo-electric module. Such a sterilizer consists of ozone generator in a shape of flat electrodes covered with dielectric material and a high-voltage pulsed power supply of 250 W. The sterilization camera was equipped with ultrasonic source operated at 100 W. The experiments on the inactivation of bacteria of the Bacillus Cereus type were carried out in the distilled water saturated by ozone. The ozone concentration in the aqueous solution was 10 mg/1, whereas the ozone concentration at the output of ozone generator was 30 mg/1. The complete inactivation of spores took 15 min. Selection of the temperature of water, the ozone concentrations and ultrasonic power allowed to determine the time necessary for destroying the row of microorganisms.

  14. Nonenzymatic microorganism identification based on ribosomal RNA

    NASA Astrophysics Data System (ADS)

    Ives, Jeffrey T.; Pierini, Alicia M.; Stokes, Jeffrey A.; Wahlund, Thomas M.; Read, Betsy; Bechtel, James H.; Bronk, Burt V.

    1999-11-01

    Effective defense against biological warfare (BW) agents requires rapid, fieldable and accurate systems. For micro- organisms like bacteria and viruses, ribosomal RNA (rRNA) provides a valuable target with multiple advantages of species specificity and intrinsic target amplification. Vegetative and spore forms of bacteria contain approximately 104 copies of rRNA. Direct detection of rRNA copies can eliminate some of the interference and preparation difficulties involved in enzymatic amplification methods. In order to apply the advantages of rRNA to BW defense, we are developing a fieldable system based on 16S rRNA, physical disruption of the micro-organism, solid phase hybridization, and fluorescence detection. Our goals include species-specific identification, complete operation from raw sample to identification in 15 minutes or less, and compact, fieldable instrumentation. Initial work on this project has investigated the lysis and hybridization steps, the species-specificity of oligonucleotides probes, and the development of a novel electromagnetic method to physically disrupt the micro- organisms. Target bacteria have been Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis). Continuing work includes further development of methods to rapidly disrupt the micro-organisms and release the rRNA, improved integration and processing, and extension to bacterial and mammalian viruses like MS2 and vesicular stomatitis virus.

  15. Medical Significance of Microorganisms in Spacecraft Environment

    NASA Technical Reports Server (NTRS)

    Pierson, Duane L.; Ott, C. Mark

    2007-01-01

    Microorganisms can spoil food supplies, contaminate drinking water, release noxious volatile compounds, initiate allergic responses, contaminate the environment, and cause infectious diseases. International acceptability limits have been established for bacterial and fungal contaminants in air and on surfaces, and environmental monitoring is conducted to ensure compliance. Allowable levels of microorganism in water and food have also been established. Environmental monitoring of the space shuttle, the Mir, and the ISS have allowed for some general conclusions. Generally, the bacteria found in air and on interior surfaces are largely of human origin such as Staphylococcus spp., Micrococcus spp. Common environmental genera such as Bacillus spp. are the most commonly isolated bacteria from all spacecraft. Yeast species associated with humans such as Candida spp. are commonly found. Aspergillus spp., Penicillium spp., and Cladosporium spp. are the most commonly isolated filamentous fungi. Microbial levels in the environment differ significantly depending upon humidity levels, condensate accumulation, and availability of carbon sources. However, human "normal flora" of bacteria and fungi can result in serious, life-threatening diseases if human immunity is compromised. Disease incidence is expected to increase as mission duration increases.

  16. Importance of the substrate nature to preserve microorganisms' cultivability in electrostatic air samplers

    NASA Astrophysics Data System (ADS)

    Roux, Jean-Maxime; Rongier, Anaëlle; Jary, Dorothée

    2015-10-01

    Recent research shows that electrostatic precipitation is a gentle method to collect airborne microorganisms and preserve their cultivability. However, the corona discharge used to charge the particles and the high electric field used to capture them are known to have a germicidal effect. The present paper investigates this paradoxical situation. Vegetative cells of E. coli and B. subtilis and spores of A. fumigatus and B. subtilis were deposited on different media and subjected to electrostatic fields of different strengths and polarities for controlled time periods. Vegetative cells are inactivated on cultivation agar plates, but remain cultivable when exposed on a stainless steel electrode and transferred afterwards onto agar plates. For the investigated conditions, spores were not affected by the corona discharge. Further experiments with a pH indicator show that chemical reactions occur when an aqueous media is exposed to the discharge. Some of these reactions are likely to create hydrogen peroxide which is known to kill a broad range of microorganisms. It is therefore highlighted that collecting electrodes in electrostatic air samplers should rather be dry conductive media.

  17. Can imazapic and seeding be applied simultaneously to rehabilitate medusahead-invaded rangeland? Single vs. multiple entry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It has recently been proposed that reducing the cost of rehabilitating medusahead (Taeniatherum caput-medusae (L.) Nevski)-invaded rangelands may be attained by seeding desired vegetation with a concurrent application of the pre-emergent herbicide (imazapic). However, the efficacy of this “single e...

  18. Bulged Invader probes: activated duplexes for mixed-sequence dsDNA recognition with improved thermodynamic and kinetic profiles.

    PubMed

    Guenther, Dale C; Karmakar, Saswata; Hrdlicka, Patrick J

    2015-10-18

    Double-stranded oligonucleotides with +1 interstrand zipper arrangements of intercalator-functionalized nucleotides are energetically activated for recognition of mixed-sequence double-stranded DNA. Incorporation of nonyl (C9) bulges at specific positions of these probes, results in more highly affine (>5-fold), faster (>4-fold) and more persistent dsDNA recognition relative to conventional Invader probes. PMID:26314212

  19. Invader disruption of belowground plant mutualisms reduces carbon acquisition and alters allocation patterns in a native forest herb.

    PubMed

    Hale, Alison N; Lapointe, Line; Kalisz, Susan

    2016-01-01

    Invasive plants impose novel selection pressures on naïve mutualistic interactions between native plants and their partners. As most plants critically rely on root fungal symbionts (RFSs) for soil resources, invaders that disrupt plant-RFS mutualisms can significantly depress native plant fitness. Here, we investigate the consequences of RFS mutualism disruption on native plant fitness in a glasshouse experiment with a forest invader that produces known anti-fungal allelochemicals. Over 5 months, we regularly applied either green leaves of the allelopathic invader Alliaria petiolata, a nonsystemic fungicide to simulate A. petiolata's effects, or green leaves of nonallelopathic Hesperis matronalis (control) to pots containing the native Maianthemum racemosum and its RFSs. We repeatedly measured M. racemosum physiology and harvested plants periodically to assess carbon allocation. Alliaria petiolata and fungicide treatment effects were indistinguishable: we observed inhibition of the RFS soil hyphal network and significant reductions in M. racemosum physiology (photosynthesis, transpiration and conductance) and allocation (carbon storage, root biomass and asexual reproduction) in both treatments relative to the control. Our findings suggest a general mechanistic hypothesis for local extinction of native species in ecosystems challenged by allelopathic invaders: RFS mutualism disruption drives carbon stress, subsequent declines in native plant vigor, and, if chronic, declines in RFS-dependent species abundance. PMID:26506529

  20. Prairie dogs increase fitness by killing interspecific competitors.

    PubMed

    Hoogland, John L; Brown, Charles R

    2016-03-30

    Interspecific competition commonly selects for divergence in ecology, morphology or physiology, but direct observation of interspecific competition under natural conditions is difficult. Herbivorous white-tailed prairie dogs (Cynomys leucurus) employ an unusual strategy to reduce interspecific competition: they kill, but do not consume, herbivorous Wyoming ground squirrels (Urocitellus elegans) encountered in the prairie dog territories. Results from a 6-year study in Colorado, USA, revealed that interspecific killing of ground squirrels by prairie dogs was common, involving 47 different killers; 19 prairie dogs were serial killers in the same or consecutive years, and 30% of female prairie dogs killed at least one ground squirrel over their lifetimes. Females that killed ground squirrels had significantly higher annual and lifetime fitness than non-killers, probably because of decreased interspecific competition for vegetation. Our results document the first case of interspecific killing of competing individuals unrelated to predation (IK) among herbivorous mammals in the wild, and show that IK enhances fitness for animals living under natural conditions. PMID:27009223