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1

Killing of microorganisms by pulsed electric fields  

Microsoft Academic Search

Lethal effects of pulsed electric fields (PEF) on suspensions of various bacteria, yeast, and spores in buffer solutions and\\u000a liquid foodstuffs were examined. Living-cell counts of vegetative cell types were reduced by PEF treatment by up to more than\\u000a four orders of magnitude (> 99.99%). On the other hand, endoand ascospores were not inactivated or killed to any great extent.

T. Grahl; H. Märkl

1996-01-01

2

Emerging and opportunistic diseases are caused by a microorganism invading a new  

E-print Network

Emerging and opportunistic diseases are caused by a microorganism invading a new habitat, either is derived from population ecology, where the `sink' population is only maintained by immigration from­sink model Source­sink ecological models6 were developed, and are currently applied, in the population

Gomulkiewicz, Richard

3

Plankton Microorganisms Coinciding with Two Consecutive Mass Fish Kills in a Newly Reconstructed Lake  

PubMed Central

Lake Karla, Greece, was dried up in 1962 and its refilling started in 2009. We examined the Cyanobacteria and unicellular eukaryotes found during two fish kill incidents, in March and April 2010, in order to detect possible causative agents. Both microscopic and molecular (16S/18S rRNA gene diversity) identification were applied. Potentially toxic Cyanobacteria included representatives of the Planktothrix and Anabaena groups. Known toxic eukaryotes or parasites related to fish kill events were Prymnesium parvum and Pfiesteria cf. piscicida, the latter being reported in an inland lake for the second time. Other potentially harmful microorganisms, for fish and other aquatic life, included representatives of Fungi, Mesomycetozoa, Alveolata, and Heterokontophyta (stramenopiles). In addition, Euglenophyta, Chlorophyta, and diatoms were represented by species indicative of hypertrophic conditions. The pioneers of L. Karla's plankton during the first months of its water refilling process included species that could cause the two observed fish kill events. PMID:22654619

Oikonomou, Andreas; Katsiapi, Matina; Karayanni, Hera; Moustaka-Gouni, Maria; Kormas, Konstantinos Ar.

2012-01-01

4

Hallmarks, Invading tissues: Hanahan  

NSDL National Science Digital Library

Professor Douglas Hanahan discusses how cancers kill you, in general, not just because they grow into a large lump, but because they invade into normal tissues and disrupt the functions of those tissues.

2009-12-26

5

Invasional meltdown: invader-invader mutualism facilitates a secondary invasion.  

PubMed

In multiply invaded ecosystems, introduced species should interact with each other as well as with native species. Invader-invader interactions may affect the success of further invaders by altering attributes of recipient communities and propagule pressure. The invasional meltdown hypothesis (IMH) posits that positive interactions among invaders initiate positive population-level feedback that intensifies impacts and promotes secondary invasions. IMH remains controversial: few studies show feedback between invaders that amplifies their effects, and none yet demonstrate facilitation of entry and spread of secondary invaders. Our results show that supercolonies of an alien ant, promoted by mutualism with introduced honeydew-secreting scale insects, permitted invasion by an exotic land snail on Christmas Island, Indian Ocean. Modeling of land snail spread over 750 sites across 135 km2 over seven years showed that the probability of land snail invasion was facilitated 253-fold in ant supercolonies but impeded in intact forest where predaceous native land crabs remained abundant. Land snail occurrence at neighboring sites, a measure of propagule pressure, also promoted land snail spread. Site comparisons and experiments revealed that ant supercolonies, by killing land crabs but not land snails, disrupted biotic resistance and provided enemy-free space. Predation pressure on land snails was lower (28.6%), survival 115 times longer, and abundance 20-fold greater in supercolonies than in intact forest. Whole-ecosystem suppression of supercolonies reversed the probability of land snail invasion by allowing recolonization of land crabs; land snails were much less likely (0.79%) to invade sites where supercolonies were suppressed than where they remained intact. Our results provide strong empirical evidence for IMH by demonstrating that mutualism between invaders reconfigures key interactions in the recipient community. This facilitates entry of secondary invaders and elevates propagule pressure, propagating their spread at the whole-ecosystem level. We show that identification and management of key facilitative interactions in invaded ecosystems can be used to reverse impacts and restore resistance to further invasions. PMID:21939072

Green, Peter T; O'Dowd, Dennis J; Abbott, Kirsti L; Jeffery, Mick; Retallick, Kent; Mac Nally, Ralph

2011-09-01

6

Microorganism immobilization  

DOEpatents

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.

Compere, Alicia L. (Knoxville, TN); Griffith, William L. (Oak Ridge, TN)

1981-01-01

7

Killing Begets Killing: Evidence From a Bug-Killing Paradigm That Initial Killing Fuels Subsequent Killing  

Microsoft Academic Search

Killing appears to perpetuate itself even in the absence of retaliation. This phenomenon may occur in part as a means to justify prior killing and so ease the threat of prior killing. Additionally, this effect should arise particularly when a killer perceives similarity to the victims, because similarity should exacerbate threat from killing. To examine these ideas we developed a

Andy Martens; Spee Kosloff; Jeff Greenberg; M. J. Landau; T. Schmader

2007-01-01

8

Early Parasitoid Recruitment in Invading Cynipid Galls  

Microsoft Academic Search

Biological invasions are widely seen as the biggest threat to biodiversity next to the loss of habitats. One aspect of considerable\\u000a interest is the recruitment of natural enemies after the establishment of the invad-ing species and how such enemies link\\u000a invaders to native communities. However, not all invaders are invasive. Eight cynipid species originating in south-eastern\\u000a Europe invaded Britain over

Karsten Schönrogge; Seiichi Moriya; George Melika; Zoë Randle; Tracey Begg; Alexandre Aebi; Graham N. Stone

9

Activation of AMPK Enhances Neutrophil Chemotaxis and Bacterial Killing  

PubMed Central

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

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

2013-01-01

10

Why do Invasive Species Successfully Establish & Invade?  

E-print Network

Why do Invasive Species Successfully Establish & Invade? #12;Many are introduced, few become invasive #12;Hypotheses about why invaders succeed: 1. Invasive species have traits that favor establishment and spread 2. Invasive species are released from enemies 3. Invasive species exploit empty niches

Schweik, Charles M.

11

Classifying Microorganisms.  

ERIC Educational Resources Information Center

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)

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

2002-01-01

12

Treponema pallidum Invades Intercellular Junctions of Endothelial Cell Monolayers  

NASA Astrophysics Data System (ADS)

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.

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

1988-05-01

13

Perennial Pepperweed (Lepidium latifolium): Properties of Invaded  

E-print Network

Perennial Pepperweed (Lepidium latifolium): Properties of Invaded Tidal Marshes Laura K. Reynolds and Katharyn E. Boyer* Lepidium latifolium (perennial pepperweed) is recognized as a threat to wetland habitats vs. effect for several soil characteristics. Nomenclature: Perennial pepperweed, Lepidium latifolium

Boyer, Katharyn

14

Plant Sacrifices Cells to Fight Invaders  

NSF Publications Database

... 05-083Plant Sacrifices Cells to Fight Invaders Gene ensures programmed cell suicide does not go ... --programmed cell death (PCD). Plants use PCD to create a protective zone of dead cells around the ...

15

Streptococcus pneumoniae Invades Erythrocytes and Utilizes Them to Evade Human Innate Immunity  

PubMed Central

Streptococcus pneumoniae, a Gram-positive bacterium, is a major cause of invasive infection-related diseases such as pneumonia and sepsis. In blood, erythrocytes are considered to be an important factor for bacterial growth, as they contain abundant nutrients. However, the relationship between S. pneumoniae and erythrocytes remains unclear. We analyzed interactions between S. pneumoniae and erythrocytes, and found that iron ion present in human erythrocytes supported the growth of Staphylococcus aureus, another major Gram-positive sepsis pathogen, while it partially inhibited pneumococcal growth by generating free radicals. S. pneumoniae cells incubated with human erythrocytes or blood were subjected to scanning electron and confocal fluorescence microscopic analyses, which showed that the bacterial cells adhered to and invaded human erythrocytes. In addition, S. pneumoniae cells were found associated with human erythrocytes in cultures of blood from patients with an invasive pneumococcal infection. Erythrocyte invasion assays indicated that LPXTG motif-containing pneumococcal proteins, erythrocyte lipid rafts, and erythrocyte actin remodeling are all involved in the invasion mechanism. In a neutrophil killing assay, the viability of S. pneumoniae co-incubated with erythrocytes was higher than that without erythrocytes. Also, H2O2 killing of S. pneumoniae was nearly completely ineffective in the presence of erythrocytes. These results indicate that even when S. pneumoniae organisms are partially killed by iron ion-induced free radicals, they can still invade erythrocytes. Furthermore, in the presence of erythrocytes, S. pneumoniae can more effectively evade antibiotics, neutrophil phagocytosis, and H2O2 killing. PMID:24194877

Yamaguchi, Masaya; Terao, Yutaka; Mori-Yamaguchi, Yuka; Domon, Hisanori; Sakaue, Yuuki; Yagi, Tetsuya; Nishino, Kunihiko; Yamaguchi, Akihito; Nizet, Victor; Kawabata, Shigetada

2013-01-01

16

Salinity tolerance of Great Lakes invaders  

Microsoft Academic Search

SUMMARY 1. The Laurentian Great Lakes are among the most invaded freshwater ecosystems in the world. Historically, the major vector for the introduction of non-indigenous species (NIS) has been the release of contaminated ballast water via transoceanic ships. Despite regulations implemented in 1993, requiring vessels carrying fresh ballast water to exchange this water with saline ocean water, new reports of

SANDRA ELLIS; HUGH J. MACISAAC

2009-01-01

17

Space Invading Systems Code Cristiano Calcagno2  

E-print Network

programs, and test our ideas against real- world systems code, starting with a Windows device driver Yang1 1 Queen Mary University of London 2 Imperial College 1 Introduction Space Invader is a static analysis tool that aims to perform accurate, automatic verification of the way that programs use pointers

O'Hearn, Peter

18

Ion-kill dosimetry  

NASA Technical Reports Server (NTRS)

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'.

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

2001-01-01

19

Killing Spinor Identities  

Microsoft Academic Search

We have found generic Killing spinor identities which bosonic equations of motion have to satisfy in supersymmetric theories if the solutions admit Killing spinors. Those identities constrain possible quantum corrections to bosonic solutions with unbroken supersymmetries. As an application we show that purely electric static extreme dilaton black holes may acquire specific quantum corrections, but the purely magnetic ones cannot.

Renata Kallosh; Tomas Ortin

1993-01-01

20

Killing Spinor Identities  

E-print Network

We have found generic Killing spinor identities which bosonic equations of motion have to satisfy in supersymmetric theories if the solutions admit Killing spinors. Those identities constrain possible quantum corrections to bosonic solutions with unbroken supersymmetries. As an application we show that purely electric static extreme dilaton black holes may acquire specific quantum corrections, but the purely magnetic ones cannot.

Renata Kallosh; Tomas Ortin

1993-06-18

21

BB Guns Can Kill  

MedlinePLUS

... Kill BB guns can kill a person. High-velocity BB guns, which have muzzle velocities higher than 350 feet per second, can increase ... do not realize that BB guns, especially high-velocity guns, can cause death. Therefore the CPSC warns ...

22

The Invader ® assay for SNP genotyping  

Microsoft Academic Search

The Invader® assay uses a structure-specific flap endonuclease (FEN) to cleave a three-dimensional complex formed by hybridization of allele-specific overlapping oligonucleotides to target DNA containing a single nucleotide polymorphism (SNP) site. Annealing of the oligonucleotide complementary to the SNP allele in the target molecule triggers the cleavage of the oligonucleotide by cleavase, a thermostable FEN. Cleavage can be detected by

Michael Olivier

2005-01-01

23

Homogeneous Killing spinor spacetimes  

NASA Astrophysics Data System (ADS)

A classification of Petrov-type D Killing spinor spacetimes admitting a homogeneous conformal representant is presented. For each class a canonical line element is constructed and a physical interpretation of its conformal members is discussed.

Van den Bergh, N.

2011-12-01

24

HOW NEUTROPHILS KILL MICROBES  

Microsoft Academic Search

? Abstract Neutrophils provide the first line of defense of the innate immune,sys- tem by phagocytosing, killing, and digesting bacteria and fungi. Killing was previously believed to be accomplished,by oxygen,free radicals and other reactive oxygen,species generated by the NADPH oxidase, and by oxidized halides produced by myeloperoxi- dase. We now,know,this is incorrect. The oxidase pumps,electrons into the phagocytic vacuole, thereby

Anthony W. Segal

2005-01-01

25

Instantons and Killing spinors  

Microsoft Academic Search

We investigate instantons on manifolds with Killing spinors and their cones. Examples of manifolds with Killing spinors include nearly Kaehler 6-manifolds, nearly parallel G_2-manifolds in dimension 7, Sasaki-Einstein manifolds, and 3-Sasakian manifolds. We construct a connection on the tangent bundle over these manifolds which solves the instanton equation, and also show that the instanton equation implies the Yang-Mills equation, despite

Derek Harland; Christoph Nölle

2011-01-01

26

Extrinsic Killing spinors  

Microsoft Academic Search

.  ?Under intrinsic and extrinsic curvature assumptions on a Riemannian spin manifold and its boundary, we show that there is\\u000a an isomorphism between the restriction to the boundary of parallel spinors and extrinsic Killing spinors of non-negative Killing constant. As a corollary, we prove that a complete Ricci-flat spin manifold with mean-convex boundary\\u000a isometric to a round sphere, is necessarily a

Oussama Hijazi; Sebastián Montiel

2003-01-01

27

Killing spinors are Killing vector fields in Riemannian Supergeometry  

E-print Network

Killing spinors are Killing vector fields in Riemannian Supergeometry with even part G0 ~=Spin(k, l); (k, l) the signature of (M0, g0). Killing vector fields o* *n (M, g s there exists a corresponding odd vector field Xs on M. Our * *main result is that Xs is a Killing vector

Cortés, Vicente

28

Killing spinors on Kähler manifolds  

Microsoft Academic Search

In the paper Kählerian Killing spinors are defined and their basic properties are investigated. Each Kähler manifold that admits a Kählerian Killing spinor is Einstein of odd complex dimension. Kählerian Killing spinors are a special kind of Kählerian twistor spinors. Real Kählerian Killing spinors appear for example, on closed Kähler manifolds with the smallest possible first eigenvalue of the Dirac

Klaus-Dieter Kirchberg

1993-01-01

29

Cadmium and Soil Microorganisms.  

National Technical Information Service (NTIS)

In connection with the questions of how cadmium acts on soil microorganisms and how that action affects cadmium accumulation in the plant, investigations with groups of microorganisms (fungi, bacteria and streptomycetes) and some physiological groups (nit...

I. Gruen

1984-01-01

30

Information use by an Invading Species: Do Invaders Respond More to Alarm Odors than Native Species?  

Microsoft Academic Search

Two species of crayfish were tested in the laboratory to evaluate the hypothesis that successful invaders use a broader range of chemical information than do displaced native species. The invasive species Orconectes rusticus reduced responses to food odors just as strongly when heterospecific (O. propinquus, O. virilis) alarm odors were introduced with food odors as they did when conspecific alarm

Brian A. Hazlett

2000-01-01

31

Invading predatory crustacean Dikerogammarus villosus eliminates both native and exotic species.  

PubMed Central

As the tempo of biological invasions increases, explanations and predictions of their impacts become more crucial. Particularly with regard to biodiversity, we require elucidation of interspecific behavioural interactions among invaders and natives. In freshwaters in The Netherlands, we show that the invasive Ponto-Caspian crustacean amphipod Dikerogammarus villosus is rapidly eliminating Gammarus duebeni, a native European amphipod, and Gammarus tigrinus, until now a spectacularly successful invader from North America. In the laboratory, survival of single (unguarded) female G. duebeni was significantly lower when male D. villosus were free to roam as compared with isolated within microcosms. In addition, survival of paired (guarded) female G. duebeni was significantly lower when male D. villosus as compared with male G. duebeni were present. D. villosus killed and consumed both recently moulted and, unusually, intermoult victims. Survival of G. tigrinus was significantly lower when D. villosus were free to roam as compared with isolated within microcosms and, again, both moulted and intermoult victims were preyed upon. Male D. villosus were significantly more predatory than were females, while female G. tigrinus were significantly more often preyed upon than were males. Predation by D. villosus on both species occurred over a range of water conductivities, an environmental feature previously shown to promote amphipod coexistence. This predatory invader is predicted to reduce further the amphipod diversity in a range of freshwater habitats in Europe and North America. PMID:10874746

Dick, J T; Platvoet, D

2000-01-01

32

Skew Killing spinors  

E-print Network

In this paper, we study the existence of a skew Killing spinor (see the definition below) on 2 and 3-dimensional Riemannian spin manifolds. We establish the integrability conditions and prove that these spinor fields correspond to twistor spinors in the two dimensional case while, up to a conformal change of the metric, they correspond to parallel spinors in the three dimensional case.

Habib, Georges

2011-01-01

33

Skew Killing spinors  

Microsoft Academic Search

In this paper, we study the existence of a skew Killing spinor (see the definition below) on 2 and 3-dimensional Riemannian spin manifolds. We establish the integrability conditions and prove that these spinor fields correspond to twistor spinors in the two dimensional case while, up to a conformal change of the metric, they correspond to parallel spinors in the three

Georges Habib; Julien Roth

2011-01-01

34

Killing In Good Conscience  

Microsoft Academic Search

In a recent article, Cass Sunstein and Adrian Vermeule argue that capital punishment is morally required if it will deter more killings than it inflicts. They claim that the state’s duty is to minimize murders, and that recent deterrence research shows that state executions, even if deemed murders themselves, can do so. If these findings are true, they argue, the

Eric Blumenson

2006-01-01

35

Instantons and Killing spinors  

NASA Astrophysics Data System (ADS)

We investigate instantons on manifolds with Killing spinors and their cones. Examples of manifolds with Killing spinors include nearly Kähler 6-manifolds, nearly parallel G 2-manifolds in dimension 7, Sasaki-Einstein manifolds, and 3-Sasakian manifolds. We construct a connection on the tangent bundle over these manifolds which solves the instanton equation, and also show that the instanton equation implies the Yang-Mills equation, despite the presence of torsion. We then construct instantons on the cones over these manifolds, and lift them to solutions of heterotic supergravity. Amongst our solutions are new instantons on even-dimensional Euclidean spaces, as well as the well-known BPST, quaternionic and octonionic instantons.

Harland, Derek; Nölle, Christoph

2012-03-01

36

The Fish Kill Mystery  

NSDL National Science Digital Library

In this case study, students speculate on what may have caused a major fish kill in an estuary in North Carolina. In the process, they explore how land runoff and excess nutrients affect aquatic communities, and learn about the complex life cycle of the dinoflagellate Pfiesteria. The case is appropriate for an introductory environmental science course, a general biology course that covers ecology, or a general zoology course.

Kosal, Erica F.

2003-01-01

37

Symplectic Killing spinors Svatopluk Krysl  

E-print Network

Symplectic Killing spinors Svatopluk Kr´ysl Charles University, Sokolovsk´a 83, Praha 8, Czech Killing spinor fields for this structure are sections of the symplectic spinor bundle satisfying a certain a necessary condition satisfied by a symplectic Killing spinor field. The advantage of this condition consists

Krysl, Svatopluk

38

Skew Killing spinors Georges Habib  

E-print Network

Skew Killing spinors Georges Habib , Julien Roth Abstract In this paper, we study the existence of a skew Killing spinor (see the definition below) on 2 and 3-dimensional Riemannian spin manifolds. We constructions (see [4, 6] for results in this topic). A -Killing spinor is a smooth section of the spinor

Paris-Sud XI, Université de

39

Killing, letting die and euthanasia  

Microsoft Academic Search

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

D N Husak

1979-01-01

40

Interpopulation variation in allelopathic traits informs restoration of invaded landscapes  

PubMed Central

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.

Lankau, Richard A

2012-01-01

41

Personal Space Invasions: What Happens When the Invader Asks Permission?  

ERIC Educational Resources Information Center

College students seated outdoors and alone on a university campus were approached by a same-sexed "invader" who sat nine inches or 18 inches away. The "invader" asked permission before sitting down or said nothing. Findings agree with equilibrium theory. Presented as the 1976 conference of the American Psychological Association, Washington, D.C.…

Sundstrom, Eric; Sundstrom, Mary Graehl

1977-01-01

42

Killing spinors on spheres and hyperbolic manifolds  

NASA Astrophysics Data System (ADS)

Properties of Killing spinors on spheres and hyperbolic manifolds are investigated with an emphasis on the relations to Killing vectors, conformal Killing vectors, and solutions of Maxwell's equations.

Fujii, Yasunori; Yamagishi, Kengo

1986-04-01

43

Inefficient Complement System Clearance of Trypanosoma cruzi Metacyclic Trypomastigotes Enables Resistant Strains to Invade Eukaryotic Cells  

PubMed Central

The complement system is the main arm of the vertebrate innate immune system against pathogen infection. For the protozoan Trypanosoma cruzi, the causative agent of Chagas disease, subverting the complement system and invading the host cells is crucial to succeed in infection. However, little attention has focused on whether the complement system can effectively control T. cruzi infection. To address this question, we decided to analyse: 1) which complement pathways are activated by T. cruzi using strains isolated from different hosts, 2) the capacity of these strains to resist the complement-mediated killing at nearly physiological conditions, and 3) whether the complement system could limit or control T. cruzi invasion of eukaryotic cells. The complement activating molecules C1q, C3, mannan-binding lectin and ficolins bound to all strains analysed; however, C3b and C4b deposition assays revealed that T. cruzi activates mainly the lectin and alternative complement pathways in non-immune human serum. Strikingly, we detected that metacyclic trypomastigotes of some T. cruzi strains were highly susceptible to complement-mediated killing in non-immune serum, while other strains were resistant. Furthermore, the rate of parasite invasion in eukaryotic cells was decreased by non-immune serum. Altogether, these results establish that the complement system recognizes T. cruzi metacyclic trypomastigotes, resulting in killing of susceptible strains. The complement system, therefore, acts as a physiological barrier which resistant strains have to evade for successful host infection. PMID:20300530

Cestari, Igor; Ramirez, Marcel I.

2010-01-01

44

Isolated retroperitoneal hydatid cyst invading splenic hilum.  

PubMed

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

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

2014-01-01

45

Microenvironments of soil microorganisms  

Microsoft Academic Search

Ultrastructural studies of soil micro-organisms and the microenvironments surrounding them are reviewed. Soil microfauna, and bacteria, actinomycetes and fungi, fixed and embedded in situ, were examined by electron microscopy (both transmission and scanning). In some cases ultrastructural histochemistry was used to detect and identify the organic matter with which microorganisms were associated and to examine the polymeric microbial materials (enzymes,

R. C. Foster

1988-01-01

46

Fossilization of Acidophilic Microorganisms  

Microsoft Academic Search

This study examines fossil microorganisms found in iron-rich deposits in an extreme acidic environment, the Tinto River in SW Spain. Both electron microscopy (SEM and TEM) and non-destructive in situ microanalytical techniques (EDS, EMP and XPS) were used to determine the role of permineralization and encrustation in preserving microorganisms forming biofilms in the sediments. Unicellular algae were preserved by silica

Virginia Souza-Egipsy; Angeles Aguilera; Eva Mateo-Martí; José Angel Martín-Gago; Ricardo Amils

2010-01-01

47

Microorganisms and Chemical Pollution  

ERIC Educational Resources Information Center

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…

Alexander, M.

1973-01-01

48

Dissecting impact of plant invaders: do invaders behave differently in the new range?  

PubMed

Knowledge from basic plant ecology suggests that impact of one plant species on another is driven by either competition for the same limiting resources, or by unique plant traits. These processes might be context specific, explaining a differential impact of exotic plant invaders in the native vs. introduced range. With the help of a conceptual framework, we aimed at identifying the relationship between invader biomass and impact in the invasive Centaurea stoebe by conducting pairwise competition experiments with 15 European (old) and 15 North American (new) neighboring species. Old neighbors grew larger and could use available soil moisture more efficiently for growth than new neighbors. Interestingly, biomass of C. stoebe explained a substantial amount of the variation in biomass of the coevolved neighbors, but not of the new "naive" neighbors. Thus, impact in the home range appears to be driven by competition for the same limiting resources, but by other factors in the introduced range, possibly by exploitation of resources that are not used by the new neighbors or by interference competition. This distinction has important consequences for the management of invasive species, as in our study ecosystem recovery is less likely after simple biomass reduction. PMID:24358696

Sun, Yan; Collins, Alexandra R; Schaffner, Urs; Müller-Schärer, Heinz

2013-10-01

49

Azithromycin Kills Invasive Aggregatibacter actinomycetemcomitans in Gingival Epithelial Cells  

PubMed Central

Aggregatibacter actinomycetemcomitans invades periodontal pocket epithelium and is therefore difficult to eliminate by periodontal scaling and root planing. It is susceptible to azithromycin, which is taken up by many types of mammalian cells. This led us to hypothesize that azithromycin accumulation by gingival epithelium could enhance the killing of intraepithelial A. actinomycetemcomitans. [3H]azithromycin transport by Smulow-Glickman gingival epithelial cells and SCC-25 oral epithelial cells was characterized. To test our hypothesis, we infected cultured Smulow-Glickman cell monolayers with A. actinomycetemcomitans (Y4 or SUNY 465 strain) for 2 h, treated them with gentamicin to eliminate extracellular bacteria, and then incubated them with azithromycin for 1 to 4 h. Viable intracellular bacteria were released, plated, and enumerated. Azithromycin transport by both cell lines exhibited Michaelis-Menten kinetics and was competitively inhibited by l-carnitine and several other organic cations. Cell incubation in medium containing 5 ?g/ml azithromycin yielded steady-state intracellular concentrations of 144 ?g/ml in SCC-25 cells and 118 ?g/ml in Smulow-Glickman cells. Azithromycin induced dose- and time-dependent intraepithelial killing of both A. actinomycetemcomitans strains. Treatment of infected Smulow-Glickman cells with 0.125 ?g/ml azithromycin killed approximately 29% of the intraepithelial CFU of both strains within 4 h, while treatment with 8 ?g/ml azithromycin killed ?82% of the CFU of both strains (P < 0.05). Addition of carnitine inhibited the killing of intracellular bacteria by azithromycin (P < 0.05). Thus, human gingival epithelial cells actively accumulate azithromycin through a transport system that facilitates the killing of intraepithelial A. actinomycetemcomitans and is shared with organic cations. PMID:23274657

Lai, Pin-Chuang

2013-01-01

50

Killing spinors on Lorentzian manifolds  

Microsoft Academic Search

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 ?=±12.

Christoph Bohle

2003-01-01

51

Killing spinor initial data sets  

Microsoft Academic Search

A 3+1 decomposition of the twistor and valence-2 Killing spinor equation is made using the space-spinor formalism. Conditions on initial data sets for the Einstein vacuum equations are given so that their developments contain solutions to the twistor and\\/or Killing equations. These lead to the notions of twistor and Killing spinor initial data. These notions are used to obtain a

Alfonso García-Parrado Gómez-Lobo; Juan A. Valiente Kroon

2008-01-01

52

Killing spinor initial data sets  

Microsoft Academic Search

A 3+1 decomposition of the twistor and valence-2 Killing spinor equation is made using the space spinor formalism. Conditions on initial data sets for the Einstein vacuum equations are given so that their developments contain solutions to the twistor and\\/or Killing equations. These lead to the notions of twistor and Killing spinor initial data. These notions are used to obtain

Juan A. Valiente Kroon

53

Killing spinor initial data sets  

E-print Network

A 3+1 decomposition of the twistor and valence-2 Killing spinor equation is made using the space spinor formalism. Conditions on initial data sets for the Einstein vacuum equations are given so that their developments contain solutions to the twistor and/or Killing equations. These lead to the notions of twistor and Killing spinor initial data. These notions are used to obtain a characterisation of initial data sets whose development are of Petrov type N or D.

Alfonso García-Parrado Gómez-Lobo; Juan A. Valiente Kroon

2007-12-20

54

Killing spinors on Lorentzian manifolds  

Microsoft Academic Search

Abstract: 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

C. Bohle

1999-01-01

55

Killing Spinors -- Beyond Supergravity  

E-print Network

This is a doctoral thesis on the application of techniques originally developed in the programme of characterisation of supersymmetric solutions to Supergravity theories, to finding alternative backgrounds. We start by discussing the concept of a Killing spinor, and how these are paramount to the process of classifying of these aforementioned supersymmetric solutions. Moreover, these geometric objects also have applications when considered in different scenarios (the 'beyond' in the title). In particular, techniques based on a parallelising rule for a spinorial field can be used for obtaining solutions to Einstein-Maxwell-De Sitter theories, as well as a (partial) classification of Lorentzian Einstein-Weyl manifolds, a problem of geometrical interest. The annexe contain an introduction and summary in Spanish language. The appendices discuss the tensorial and spinorial conventions employed, some relevant geometrical information on the scalar manifolds for the matter contents of interest, as well as for the nul...

Palomo-Lozano, Alberto

2012-01-01

56

CASE REPORT Osteoid Osteoma Invading the Posterior Labyrinth  

E-print Network

the cochlea but invaded the posterior labyrinth and the endolymphatic duct. There was a close relationship tumors.1,2 It is most frequently seen in teenagers and young adults and is very rare after 30 years

57

Bioplastics from microorganisms  

Microsoft Academic Search

The term ‘biomaterials’ includes chemically unrelated products that are synthesised by microorganisms (or part of them) under different environmental conditions. One important family of biomaterials is bioplastics. These are polyesters that are widely distributed in nature and accumulate intracellularly in microorganisms in the form of storage granules, with physico-chemical properties resembling petrochemical plastics. These polymers are usually built from hydroxy-acyl–CoA

José M Luengo; Belén Garc??a; Angel Sandoval; Germán Naharro; El??as R Olivera

2003-01-01

58

Influence of an invaded zone on a multiprobe formation tester  

SciTech Connect

When an oil or gas well is being drilled, some of the borehole fluid (mud filtrate) leaks into the formation, displacing the native reservoir fluid. This creates an invaded zone around the wellbore. The invading fluid will generally have a mobility and compressibility that differ from the formation fluid. The presence of the invaded zone will affect the pressure transients measured by a formation tester. In this paper, a model that includes an invaded zone is presented together with an analysis of its effect at each of the probes of a multiple probe formation tester. The results show that the properties of the invaded zone dominate the pressure transient measured at the sink probe, strongly influence the transient at the horizontal probe, and only modestly affect the vertical probe transient. A suggested modification to the current interpretation procedure (which does not consider the invaded zone) for determining the horizontal and vertical mobility is also presented. The application of this modified procedure is discussed using a model example.

Goode, P.A.; Thambynayagam, R.K.M. [Schlumberger-Doll Research, Ridgefield, CT (United States)

1996-03-01

59

Conflict theory and police killings  

Microsoft Academic Search

Although there has been considerable interest in the homicide of law enforcement officers, there has been little systematic analysis of the effects of structural variables on police killings across macro social units. Recently, Peterson and Bailey (1988) have examined the macro social determinants of police killings within a theoretical context and concluded that social conditons which bring civilians and law

Mitchell B. Chamlin

1989-01-01

60

Fossil Microorganisms in Archaean  

NASA Technical Reports Server (NTRS)

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.

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

2006-01-01

61

How electroshock weapons kill!  

NASA Astrophysics Data System (ADS)

Growing numbers of law enforcement officers now carry an electroshock weapon (ESW). Over 500 U.S. deaths have followed ESW use in the past 26 years; over 450 of these deaths followed use of an electromuscular disruptor in the past 9 years. Most training courses teach that ESWs are safe; that they can kill only by the direct effect of electric current on the heart; and that a death following use of an ESW always has some other cause. All these teachings are false! The last was disproved by Lundquist.^1 Williams^2 ruled out direct electrical effects as a cause of almost all the 213 deaths he studied, leaving disruption of normal physiological processes as the only alternative explanation. Careful study of all such deaths identifies 4 different ways that death has or could have been brought about by the ESW: kidney failure following rhabdomyolysis [rare]; cardiac arrest from hyperkalemia following rhabdomyolysis [undocumented]; lactic acid-induced ventricular fibrillation [conclusive proof impossible]; and [most common] anoxia from so much lactic acid in the circulating blood that it acts as an oxygen scavenger, continuously depleting the blood of oxygen until most of the lactate has been metabolized. ^1M. Lundquist, BAPS 54(1) K1.270(2009). ^2Howard E. Williams, Taser Electronic Control Devices and Sudden In-Custody Death, 2008.

Lundquist, Marjorie

2010-03-01

62

Killing spinors are Killing vector fields in Riemannian Supergeometry  

E-print Network

A supermanifold M is canonically associated to any pseudo Riemannian spin manifold (M_0,g_0). Extending the metric g_0 to a field g of bilinear forms g(p) on T_p M, p\\in M_0, the pseudo Riemannian supergeometry of (M,g) is formulated as G-structure on M, where G is a supergroup with even part G_0\\cong Spin(k,l); (k,l) the signature of (M_0,g_0). Killing vector fields on (M,g) are, by definition, infinitesimal automorphisms of this G-structure. For every spinor field s there exists a corresponding odd vector field X_s on M. Our main result is that X_s is a Killing vector field on (M,g) if and only if s is a twistor spinor. In particular, any Killing spinor s defines a Killing vector field X_s.

D. V. Alekseevsky; V. Cortés; C. Devchand; U. Semmelmann

1997-04-02

63

Killing spinors are Killing vector fields in Riemannian supergeometry  

NASA Astrophysics Data System (ADS)

A supermanifold M is canonically associated to any pseudo-Riemannian spin manifold ( M0, g0). Extending the metric g0 to a field g of bilinear forms g( p) on TpM, p?M0, the pseudo-Riemannian supergeometry of ( M, g) is formulated as G-structure on M, where G is a supergroup with even part G 0 ? Spin(k, l); (k, l) the signature of ( M0, go). Killing vector fields on ( M, g) are, by definition, infinitesimal automorphisms of this G-structure. For every spinor field s there exists a corresponding odd vector field Xs on M. Our main result is that Xs is a Killing vector field on ( M, g) if and only if s is a twistor spinor. In particular, any Killing spinor s defines a Killing vector field Xs.

Alekseevsky, D. V.; Cortés, V.; Devchand, C.; Semmelmann, U.

1998-06-01

64

Killing spinors on spheres and hyperbolic manifolds  

Microsoft Academic Search

Properties of Killing spinors on spheres and hyperbolic manifolds are investigated with an emphasis on the relations to Killing vectors, conformal Killing vectors, and solutions of Maxwell’s equations.

Yasunori Fujii; Kengo Yamagishi

1986-01-01

65

Microorganisms and Man.  

ERIC Educational Resources Information Center

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)

Noble, W. C.

1983-01-01

66

Subsurface Microorganisms: Ecological significance  

SciTech Connect

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.

Fredrickson, Jim K.

2003-01-15

67

Polysaccharides from Extremophilic Microorganisms  

Microsoft Academic Search

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

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

2004-01-01

68

Comparing Sizes of Microorganisms  

NSDL National Science Digital Library

In this activity related to microbes, learners create scale models of microorganisms and compare relative sizes of common bacteria, viruses, fungi and protozoa using metric measures: meters, centimeters and micrometers. Learners will discover that microbes come in many different sizes and shapes, and frequently are measured in micrometers. This lesson guide includes background information and handouts.

Moreno, Nancy P.; Tharp, Barbara Z.; Erdmann, Deanne B.; Clayton, Sonia R.; Denk, James P.

2008-01-01

69

Real Killing spinors and holonomy  

Microsoft Academic Search

We give a description of all complete simply connected Riemannian manifolds carrying real Killing spinors. Furthermore, we present a construction method for manifolds with the exceptional holonomy groupsG2 and Spin(7).

Christian Bär

1993-01-01

70

Killing spinors and gravitational perturbations  

Microsoft Academic Search

It is shown that in a vacuum space-time, possibly with a nonzero cosmological constant, which admits a D(1,0) Killing spinor, one component of the perturbed Weyl spinor that satisfies a decoupled equation, when multiplied by an appropriate factor made out of the components of the Killing spinor, constitutes a Debye potential that generates metric perturbations of the considered background. It

G. F. Torres del Castillo

1986-01-01

71

Mechanism of lethal action of 2,450-MHz radiation on microorganisms.  

PubMed Central

Various bacteria, actinomycetes, fungi, and bacteriophages were exposed to microwaves of 2,450 +/- 20 MHz in the presence and in the absence of water. It was found that microorganisms were inactivated only when in the presence of water and that dry or lyophilized organisms were not affected even by extended exposures. The data presented here prove that microorganisms are killed by "thermal effect" only and that, most likely, there is no "nonthermal effect"; cell constituents other than water do not absorb sufficient energy to kill microbial cells. PMID:453828

Vela, G R; Wu, J F

1979-01-01

72

Kills Germs by the Millions!  

ERIC Educational Resources Information Center

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)

Swails, Molly

1980-01-01

73

Inactivation of Microorganisms  

NASA Astrophysics Data System (ADS)

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).

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

74

Exogenous myeloperoxidase enhances bacterial phagocytosis and intracellular killing by macrophages.  

PubMed Central

It is well documented that myeloperoxidase (MyPo) contributes to the bacterial activities of neutrophils and monocytes. Since mature macrophages (M phi) are devoid of this enzyme, its participation in M phi-mediated phagocytes and bacterial killing has not been completely defined. The present study demonstrates the exogenously added MyPo, at physiological levels, enhances both phagocytosis and killing of Escherichia coli. Murine peritoneal M phi were exposed to various concentrations of MyPo for different time intervals. Viable opsonized E. coli was added either prior to or after addition of MyPo. Thioglycolate-induced but not resident M pho exhibited an increase in the number of phagocytizing cells. Both resident and thioglycolate-induced M phi demonstrated increased bactericidal activity. Physiological levels of soluble MyPo also induced a significant increase in chemiluminescence. Since luminol-dependent chemiluminescence measures reactive oxygen intermediate production, studies were done to determine whether superoxide anion or H2O2 was involved in MyPo-induced M pho killing. Both superoxide dismutase and catalase ablated MyPo-induced bactericidal activity. The above data suggest that soluble MyPo, released from neutrophils at a site of infection or inflammation, can enhance both phagocytosis and killing of microorganisms. PMID:7622228

Lincoln, J A; Lefkowitz, D L; Cain, T; Castro, A; Mills, K C; Lefkowitz, S S; Moguilevsky, N; Bollen, A

1995-01-01

75

Leaf Litter Disappearance in Earthworm-Invaded Northern  

E-print Network

Leaf Litter Disappearance in Earthworm-Invaded Northern Hardwood Forests: Role of Tree Species, and forest floor structure and composition are not well understood. For 2 years, we compared disappearance Department of Forest Resources, University of Minnesota, 1530 N. Cleveland Ave., St. Paul, Minnesota 55108

Minnesota, University of

76

18 BBC History December 2004 SERIES OF invaders  

E-print Network

18 BBC History December 2004 A SERIES OF invaders ­ Berbers, Moors and Spanish ­ readily History NATIONALMARITIMEMUSEUM Catholic communities of Malta, Portugal and the Italian port city of Genoa revealed there were 3,201 inhabitants including Genoese, British, Irish, Portuguese, French and Minorcans

Royal Holloway, University of London

77

Secondary imbibition in NAPL-invaded mixed-wet sediments  

E-print Network

of NAPL by waterflooding a mixed-wet soil. We use a 3D disordered pore network with a realistic most soils and rocks are naturally strongly water-wet, NAPL invasion may alter their wettabilitySecondary imbibition in NAPL-invaded mixed-wet sediments Ahmed Al-Futaisia,b , Tad W. Patzekb

Patzek, Tadeusz W.

78

Culture Clash Invades Miami: Oral Histories and Ethnography Center Stage  

ERIC Educational Resources Information Center

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…

Garcia, David G.

2008-01-01

79

A taste for novelty in invading house sparrows, Passer domesticus  

Microsoft Academic Search

One of the central questions in invasion biology involves why some introductions succeed and others fail. Although several correlates of invasion success have been identified, patterns alone cannot identify the mechanisms underlying the invasion process. Here, we test the hypothesis that one predictor of invasion success, behavioral flexibility, is different between invading and established populations of the same species of

Lynn B. Martin II; Lisa Fitzgerald

2005-01-01

80

Invading parasites cause a structural shift in red fox dynamics  

E-print Network

Invading parasites cause a structural shift in red fox dynamics Mads C. Forchhammer1,2* and Tommy epizootic in Fennoscandia reduced the abundance of red fox by over 70%. While the numerical responses of red, knowledge of how sarcoptic mange a¡ects the structure of the dynamics of red fox populations is lacking

Forchhammer, Mads C.

81

Plasmodium ookinetes coopt mammalian plasminogen to invade the mosquito midgut  

E-print Network

Plasmodium ookinetes coopt mammalian plasminogen to invade the mosquito midgut Anil K. Ghosha, and approved August 30, 2011 (received for review March 6, 2011) Ookinete invasion of the mosquito midgut is an essential step for the development of the malaria parasite in the mosquito. Invasion involves recognition

Arnold, Jonathan

82

Ecology and Restoration of Invaded Ecosystems FOR 6934 (3 credits)  

E-print Network

Ecology and Restoration of Invaded Ecosystems FOR 6934 (3 credits) Spring 2014 Course Description This advanced ecosystem management course will begin with an overview of the ecological basis for plant in ecology and applied plant science, graduate students in the Masters of Science, Ecological Restoration

Watson, Craig A.

83

Ecology and Restoration of Invaded Ecosystems FOR 4934 (3 credits)  

E-print Network

Ecology and Restoration of Invaded Ecosystems FOR 4934 (3 credits) Spring 2014 Course Description This advanced ecosystem management course will begin with an overview of the ecological basis for plant in ecology and applied plant science, graduate students in the Masters of Science, Ecological Restoration

Slatton, Clint

84

Original article Pollination efficiency of native and invading  

E-print Network

Original article Pollination efficiency of native and invading Africanized bees in the tropical dry) Summary — We compared the pollinator effectiveness of native and exotic bees on Kallstroemia gran Trigona nigra. Thus, when all measures of pollinator effectiveness are combined, exotic bees appear

Paris-Sud XI, Université de

85

INVASIONS AND INFECTIONS Invading with biological weapons: the importance of  

E-print Network

INVASIONS AND INFECTIONS Invading with biological weapons: the importance of disease with introduced parasites), there is the potential that the disease can act as a `biological weapon' leading weapons ­ their diseases ­ with them, and concurrently, the emergence of disease within the native

White, Andrew

86

Treponema pallidum Invades Intercellular Junctions of Endothelial Cell Monolayers  

Microsoft Academic Search

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

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

1988-01-01

87

Phosphate-Solubilizing Microorganisms  

Microsoft Academic Search

\\u000a Phosphorus plays a significant role in several physiological and biochemical activities such as photosynthesis, transformation\\u000a of sugar to starch, and other biological processes in plants. Phosphorus in soils is immobilized due to formation of insoluble\\u000a complexes such as iron and aluminium hydrous oxides, crystalline and amorphous aluminium silicate and calcium carbonate. Many\\u000a soil microorganisms specially Pseudomonas, Bacillus, Aspergillus and Penicillium

Ramesh Chander Kuhad; Surender Singh; Lata; Ajay Singh

88

Fluid Mechanics of Planktonic Microorganisms  

E-print Network

Fluid Mechanics of Planktonic Microorganisms Jeffrey S. Guasto,1,2 Roberto Rusconi,1 and Roman of the morphologies, propulsion mechanisms, flow envi- ronments, and behaviors of planktonic microorganisms has long planktonic microorganisms (1 mm). In the past few years, the field has witnessed an increasing number

Entekhabi, Dara

89

3, 273307, 2006 Microorganisms in  

E-print Network

BGD 3, 273­307, 2006 Microorganisms in seafloor basalts J. Einen et al. Title Page Abstract, 273­307, 2006 Microorganisms in seafloor basalts J. Einen et al. Title Page Abstract Introduction Discussion EGU Abstract Microorganisms have been reported to be associated with the alteration of the glassy

Paris-Sud XI, Université de

90

Timelike Killing spinors in seven dimensions  

Microsoft Academic Search

We employ the G-structure formalism to study supersymmetric solutions of minimal and SU(2) gauged supergravities in seven dimensions admitting Killing spinors with associated timelike Killing vector. The most general such Killing spinor defines an 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

Marco Cariglia

2004-01-01

91

ccsd00002799, KILLING FORMS ON SYMMETRIC SPACES  

E-print Network

de#12;nitions of Killing vector #12;elds on Riemannian manifolds. A vector #12;eld X is Killing AND UWE SEMMELMANN Proposition 1.2. A symmetric space admitting real Killing spinors is locally confor carry Killing spinors is locally irreducible (cf. [3]) and using the squaring construction one can

92

Killing spinors and gravitational perturbations  

SciTech Connect

It is shown that in a vacuum space-time, possibly with a nonzero cosmological constant, which admits a D(1,0) Killing spinor, one component of the perturbed Weyl spinor that satisfies a decoupled equation, when multiplied by an appropriate factor made out of the components of the Killing spinor, constitutes a Debye potential that generates metric perturbations of the considered background. It is also shown that in the case where the background is of type N, there is an operation that relates the gravitational perturbations and the zero-rest-mass fields of spin-0, - 1/2 , and -1.

Torres del Castillo, G.F.

1986-06-01

93

dg-ga/9704002 Killing spinors are Killing vector fields in  

E-print Network

dg-ga/9704002 MPI 97-29 Killing spinors are Killing vector fields in Riemannian Supergeometry D spinor. In particular, any Killing spinor s defines a Killing vector field Xs. 1 Introduction); (k, l) the signature of (M0, g0). Killing vector fields on (M, g) are, by definition, infinitesimal

Semmelmann, Uwe

94

Antimicrobial peptides: promising compounds against pathogenic microorganisms.  

PubMed

In the last decades, the indiscriminate use of conventional antibiotics has generated high rates of microbial resistance. This situation has increased the need for obtaining new antimicrobial compounds against infectious diseases. Among these, antimicrobial peptides (AMPs) constitute a promising alternative as therapeutic agents against various pathogenic microbes. These therapeutic agents can be isolated from different organisms, being widespread in nature and synthesized by microorganisms, plants and animals (both invertebrates and vertebrates). Additionally, AMPs are usually produced by a non-specific innate immune response. These peptides are involved in the inhibition of cell growth and in the killing of several microorganisms, such as bacteria, fungi, enveloped viruses, protozoans and other parasites. They have many interesting properties as potential antibiotics, such as relatively small sizes (below 25-30 kDa), amphipathic structures, cationic nature, and offer low probability for the generation of microbial resistance. In recent years, many novel AMPs, with very promising therapeutic properties, have been discovered. These peptides have been the base for the production of chemical analogs, which have been designed, chemically synthesized and tested in vitro for their antimicrobial activity. This review is focused on antibacterial (against Gram (-) and Gram (+) bacteria) and antifungal peptides, discussing action mode of AMPs, and recent advances in the study of the molecular basis of their anti-microbial activity. Finally, we emphasize on their current pharmacological development, future directions and applications of AMPs as promising antibiotics of therapeutic use for microbial infections. PMID:24533812

Cruz, J; Ortiz, C; Guzmán, F; Fernández-Lafuente, R; Torres, R

2014-01-01

95

[Prevention and control of invaded plant Phytolacca americana in sandy coastal shelter forests].  

PubMed

The invasion of Phytolacca americana has produced serious damage to the coastal shelter forests in China. In order to search for the effective measures for controlling the growth of P. americana, several plots in the Robinia pseudoacacia forest invaded by P. Americana to the relatively same extent were installed, and the measures of physical control (mowing and root cutting) and chemical control (spraying herbicides) were adopted to control the invasion of P. Americana, taking the site with good growth of Amorpha fruticosa in the forest and without any control measures as the comparison. The results showed that mowing could rapidly decrease the growth of P. americana in the same year, but the growth recovered in the next year. 1/3 root cutting only reduced the aboveground growth of P. americana in the same year, and the growth was recovered in the third year; while 2/3 root cutting and whole cutting could effectively cleanup the P. americana plants all the time. Spraying quizalofop-p-ethyl and paraquat only killed the aboveground part of P. americana in the same year, but this part of P. americana recovered to the normal level in the next year; while spraying 45 g x L(-1) of glyphosate could completely kill the whole P. americana plants till the third year. The growth of P. americana at the site with good growth of A. fruticosa and without any control measures maintained at a low level all the time, suggesting that planting A. fruticosa in R. pseudoacacia forest would be an effective approach to prevent and control the P. americana invasion. PMID:22803465

Fu, Jun-Peng; Li, Chuan-Rong; Xu, Jing-Wei; Cheng, Wan-Li; Song, Rui-Feng; Liu, Yun

2012-04-01

96

AN EXPERIMENTAL STUDY OF PROTECTIVE INOCULATION WITH HEAT KILLED TUBERCLE BACILLI  

PubMed Central

Heat killed tubercle bacilli repeatedly injected into or below the skin of rabbits increase conspicuously their resistance against infection with virulent tubercle bacilli. Protection against tuberculous infection following the administration of heat killed tubercle bacilli to rabbits is only slightly less than that given by BCG. Addition of certain antigens, notably heated horse serum, increases the protection given by heat killed tubercle bacilli so that it is approximately the same as that afforded by BCG. These experiments and tentative observations of persons exposed to tuberculous infection indicate that heat killed tubercle bacilli may be substituted for the living attenuated microorganism in the attempt to increase resistance against tuberculous infection and to influence favorably the delicate balance between asymptomatic or latent infection and progressive manifest disease that is characteristic of human tuberculosis. PMID:19870697

Opie, Eugene L.; Freund, Jules

1937-01-01

97

Farm Education at Stony Kill.  

ERIC Educational Resources Information Center

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)

Parisio, Richard

1986-01-01

98

Euthanasia: Killing as Due Care?  

Microsoft Academic Search

Summary On 10 April 2001, the Netherlands was the first country to pass a law on the killing of patients at their request (euthanasia), which took effect on 1 April 2002. Belgium followed and passed a euthanasia law on 16 May 2002, which took effect on 23 September 2002 and is even more liberal than the Dutch one. Physicians will

Fuat S. Oduncu

2003-01-01

99

Persistence of invading gypsy moth populations in the United States  

Microsoft Academic Search

Exotic invasive species are a mounting threat to native biodiversity, and their effects are gaining more public attention\\u000a as each new species is detected. Equally important are the dynamics of exotic invasives that are previously well established.\\u000a While the literature reports many examples of the ability of a newly arrived exotic invader to persist prior to detection\\u000a and population growth,

Stefanie L. Whitmire; Patrick C. Tobin

2006-01-01

100

Exotic Plant Species Invade Hot Spots of Native Plant Diversity  

Microsoft Academic Search

Some theories and experimental studies suggest that areas of low plant spe- cies 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

Thomas J. Stohlgren; Dan Binkley; Geneva W. Chong; Mohammed A. Kalkhan; Lisa D. Schell; Kelly A. Bull; Yuka Otsuki; Gregory Newman; Michael Bashkin; Yowhan Son

1999-01-01

101

The role of research for integrated management of invasive species, invaded landscapes and communities  

Microsoft Academic Search

Summary 1. Invaded landscapes and ecosystems are composed of multiple interacting networks and feed-back loops, sometimes leading to unexpected effects of management actions. In order to plan management for invaded systems we need to explicitly consider management goals before putting actions in place. Actions taken must be justified in terms of their amelioration of impacts of invaders, contribution to the

Yvonne M. Buckley

2008-01-01

102

Killing spinors are killing vector fields in Riemannian supergeometry  

Microsoft Academic Search

A supermanifold M is canonically associated to any pseudo-Riemannian spin manifold (M0, g0). Extending the metric g0 to a field g of bilinear forms g(p) on TpM, p?M0, the pseudo-Riemannian supergeometry of (M, g) is formulated as G-structure on M, where G is a supergroup with even part G0 ? Spin(k, l); (k, l) the signature of (M0, go). Killing

D. V. Alekseevsky; V. Cortés; C. Devchand; U. Semmelmann

1998-01-01

103

Invisible invaders: non-pathogenic invasive microbes in aquatic and terrestrial ecosystems.  

PubMed

Although the number of studies on invasive plants and animals has risen exponentially, little is known about invasive microbes, especially non-pathogenic ones. Microbial invasions by viruses, bacteria, fungi and protists occur worldwide but are much harder to detect than invasions by macroorganisms. Invasive microbes have the potential to significantly alter community structure and ecosystem functioning in diverse terrestrial and aquatic ecosystems. Consequently, increased attention is needed on non-pathogenic invasive microbes, both free-living and symbiotic, and their impacts on communities and ecosystems. Major unknowns include the characteristics that make microbes invasive and properties of the resident communities and the environment that facilitate invasions. A comparison of microbial invasions with invasions of macroorganisms should provide valuable insights into general principles that apply to invasions across all domains of life and to taxon-specific invasion patterns. Invasive microbes appear to possess traits thought to be common in many invasive macroorganisms: high growth rate and resource utilization efficiency, and superior competitive abilities. Invading microorganisms are often similar to native species, but with enhanced performance traits, and tend to spread in lower diversity communities. Global change can exacerbate microbial invasions; therefore, they will likely increase in the future. PMID:21054733

Litchman, Elena

2010-12-01

104

Beetle Kill Wall at NREL  

ScienceCinema

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.

None

2013-05-29

105

Parallel and Killing Spinors on Spinc Manifolds  

Microsoft Academic Search

We describe all simply connected Spinc manifolds carrying parallel and real Killing spinors. In particular we show that every Sasakian manifold (not necessarily Einstein) carries a canonical Spinc structure with Killing spinors.

Andrei Moroianu

1996-01-01

106

Killing in Okaraygua: An Inspector Irronogaray Mystery  

E-print Network

1 Citation: Levine, Stuart. (2012) Killing in Okaraygua: An Inspector Irronogaray Mystery [Kindle Edition]. Amazon Digital Services, Amazon.com. Published version: http://www.amazon.com/Killing-Okaraygua-Inspector-Irronogaray- ebook...

Levine, Stuart

2012-09-05

107

Integrability conditions for Killing spinors  

Microsoft Academic Search

The conditions for the existence of solutions ofDµ?=±c?µ? are discussed. In general, it is not sufficient to consider only the first integrability condition [Dµ,Dv]?=-2c2?{µv}?; in particular, the second integrability condition is needed to explain why, in certain cases, only for one choice of sign does a solution exist. The Killing spinor-tensors, as defined by Walker and Penrose, are shown to

P. van Nieuwenhuizen; N. P. Warner

1984-01-01

108

The Management of Police Killings  

Microsoft Academic Search

lmost four yeArs Ago in the first issue of Crime and Social Justice, tAkAgi? (?974)?presentedananalysisofpolicekillingsofciviliansandofpolice? officers killed in the line of duty in the United States. He examined the deaths of male civilians over 10 years old caused by police intervention during a 10-year period and noted the dramatic increase of civilian deaths (especially blacks) caused by the police between

Sid Harring; Tony Platt; Richard Speiglman; Paul Takagi

109

Women who kill their mates.  

PubMed

Spousal homicide perpetrators are much more likely to be men than women. Accordingly, little research has focused on delineating characteristics of women who have committed spousal homicide. A retrospective clinical review of coroners' files containing all cases of spousal homicide occurring in Quebec over a 20-year period was carried out. A total of 276 spousal homicides occurred between 1991 and 2010, with 42 homicides by female spouses and 234 homicides by male spouses. Differences between homicides committed by female offenders and male offenders are discussed, and findings on spousal homicide committed by women are compared with those of previous studies. Findings regarding offenses perpetrated by females in the context of mental illness, domestic violence, and homicide-suicide are explored. The finding that only 28% of the female offenders in the Quebec sample had previously been subjected to violence by their victim is in contrast to the popular belief and reports that indicate that most female-perpetrated spousal homicide occurs in self-defense or in reaction to long-term abuse. In fact, women rarely gave a warning before killing their mates. Most did not suffer from a mental illness, although one-fifth were acutely intoxicated at the time of the killing. In the vast majority of cases of women who killed their mates, there were very few indicators that might have signaled the risk and helped predict the violent lethal behavior. PMID:23015414

Bourget, Dominique; Gagné, Pierre

2012-01-01

110

The geometry of D = 11 Killing spinors  

Microsoft Academic Search

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

Jerome P. Gauntlett; Stathis Pakis

2003-01-01

111

Chemotactic transduction in biomining microorganisms  

Microsoft Academic Search

The oxidative attack of ores by bioleaching microorganisms requires that the cells adhere to specific sites on the surface of the minerals. This attachment will depend on the sensing by the microorganisms of a dissolved ion concentration gradient present in the immediate vicinity of the solid. Chemotactic responses towards metal ions and other compounds have been described for Thiobacillus ferrooxidans

C. A Jerez

2001-01-01

112

KILLING SPINORS ON LORENTZIAN MANIFOLDS CHRISTOPH BOHLE  

E-print Network

and Killing vector #12;elds in the semi{Riemannian supergeometry canonically associated to a semi{ RiemannianKILLING SPINORS ON LORENTZIAN MANIFOLDS CHRISTOPH BOHLE Abstract. The aim of this paper is to describe some results concerning the geometry of Lorentzian manifolds admitting Killing spinors. We prove

113

Some basic properties of Killing spinors  

Microsoft Academic Search

The concept of Killing spinor is analyzed in a general way by using the spinorial formalism. It is shown, among other things, that higher derivatives of Killing spinors can be expressed in terms of lower order derivatives. Conformal Killing vectors are studied in some detail in the light of spinorial analysis: Classical results are formulated in terms of spinors. A

Shahen Hacyan; Jerzy Plebanski

1976-01-01

114

Imaginary Kahlerian Killing spinors I Nicolas Ginoux  

E-print Network

Imaginary K¨ahlerian Killing spinors I Nicolas Ginoux and Uwe Semmelmann February 19, 2012 Abstract-trivial imaginary K¨ahlerian Killing spinors. 1 Introduction Let (M2n , g, J) a K¨ahler manifold of real dimension 2¨ahler manifold and C. A pair (, ) of sections of M is called an -K¨ahlerian Killing spinor if and only

Semmelmann, Uwe

115

EXTRINSIC KILLING SPINORS OUSSAMA HIJAZI AND SEBASTI  

E-print Network

EXTRINSIC KILLING SPINORS OUSSAMA HIJAZI AND SEBASTI #19; AN MONTIEL Abstract. Under intrinsic that there is an isomorphism between the restriction to the boundary of parallel spinors and extrinsic Killing spinors of non-dimensional Riemannian spin manifold Q, real Killing spinors could be characterized as being eigenspinor #12;elds

Henri Poincaré -Nancy-Université, Université

116

The CIA and Targeted Killings Beyond Borders  

Microsoft Academic Search

This Article focuses on the accountability of the Central Intelligence Agency (CIA) in relation to targeted killings, under both United States law and international law. As the CIA, often in conjunction with Department of Defense (DOD) Special Operations forces, becomes more and more deeply involved in carrying out extraterritorial targeted killings both through kill\\/capture missions and drone-based missile strikes in

Philip Alston

2011-01-01

117

Killing the Police: Myths and Motives  

Microsoft Academic Search

This article analyzes the situational motives of assailants who kill New York City police in the line of duty. Contrary to popular opinion, police are not often killed during domestic disturbances nor are they the seemingly senseless victims of madmen or lunatics. Rather, New York police are more likely to be killed by rational robbers fleeing the scene of a

Mona Margarita

1980-01-01

118

Killing spinors are Killing vector fields in Riemannian Supergeometry  

Microsoft Academic Search

A supermanifold M is canonically associated to any pseudo Riemannian spin manifold (M_0,g_0). Extending the metric g_0 to a field g of bilinear forms g(p) on T_p M, p\\\\in M_0, the pseudo Riemannian supergeometry of (M,g) is formulated as G-structure on M, where G is a supergroup with even part G_0\\\\cong Spin(k,l); (k,l) the signature of (M_0,g_0). Killing vector fields

D. V. Alekseevsky; V. Cortés; C. Devchand; U. Semmelmann

1997-01-01

119

40 CFR 725.85 - Microorganism identity.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Microorganism identity. 725.85 Section...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information § 725.85 Microorganism identity. (a)...

2010-07-01

120

Forgotten creatures: A survey of microorganisms  

NSDL National Science Digital Library

Microorganisms are often overlooked in the study of biology because they are not visible to the human eye. In fact, there is a great diversity of microorganisms. Microorganisms include bacteria, protozoa, algae, lichens, and fungi.

Katie Hale (California State University, Fullerton ;Student, Biological Sciences)

2007-01-12

121

40 CFR 725.85 - Microorganism identity.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Microorganism identity. 725.85 Section...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information § 725.85 Microorganism identity. (a)...

2013-07-01

122

40 CFR 725.85 - Microorganism identity.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Microorganism identity. 725.85 Section...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information § 725.85 Microorganism identity. (a)...

2011-07-01

123

40 CFR 725.85 - Microorganism identity.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Microorganism identity. 725.85 Section...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public Access to Information § 725.85 Microorganism identity. (a)...

2012-07-01

124

Adaptive prediction of environmental changes by microorganisms  

E-print Network

ARTICLES Adaptive prediction of environmental changes by microorganisms Amir Mitchell1 , Gal H,4 * Natural habitats of some microorganisms may fluctuate erratically, whereas others, which are more to classical Pavlovian conditioning, microorganisms may have evolved to anticipate environmental stimuli

Pilpel, Yitzhak

125

Digital holographic imaging of microorganisms  

E-print Network

Imaging aquatic microorganisms in 3D space is of interest to biologists and ocean scientists seeking to understand the behavior of these organisms in their natural environments. In this research, digital holographic imaging ...

Wolf, Michael Trevor

2006-01-01

126

Sensor arrays for detecting microorganisms  

NASA Technical Reports Server (NTRS)

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.

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

2000-01-01

127

Invading parasites cause a structural shift in red fox dynamics.  

PubMed Central

The influence of parasites on host life histories and populations is pronounced. Among several diseases affecting animal populations throughout the world, sarcoptic mange has influenced many carnivore populations dramatically and during the latest epizootic in Fennoscandia reduced the abundance of red fox by over 70%. While the numerical responses of red fox populations, their prey and their competitors as well as clinical implications are well known, knowledge of how sarcoptic mange affects the structure of the dynamics of red fox populations is lacking. Integrating ecological theory and statistical modelling, we analysed the long-term dynamics (1955-1996) of 14 Danish red fox populations. As suggested by the model, invading sarcoptic mange significantly affected direct and delayed density dependence in red fox dynamics and concomitant shifts in fluctuation patterns were observed. Our statistical analyses also revealed that the spatial progressive spread of mange mites was mirrored in the autocovariate structures of red fox populations progressively exposed to sarcoptic mange. PMID:10819147

Forchhammer, M C; Asferg, T

2000-01-01

128

Group II Introns: Mobile Ribozymes that Invade DNA  

PubMed Central

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

Lambowitz, Alan M.; Zimmerly, Steven

2011-01-01

129

Invading parasites cause a structural shift in red fox dynamics.  

PubMed

The influence of parasites on host life histories and populations is pronounced. Among several diseases affecting animal populations throughout the world, sarcoptic mange has influenced many carnivore populations dramatically and during the latest epizootic in Fennoscandia reduced the abundance of red fox by over 70%. While the numerical responses of red fox populations, their prey and their competitors as well as clinical implications are well known, knowledge of how sarcoptic mange affects the structure of the dynamics of red fox populations is lacking. Integrating ecological theory and statistical modelling, we analysed the long-term dynamics (1955-1996) of 14 Danish red fox populations. As suggested by the model, invading sarcoptic mange significantly affected direct and delayed density dependence in red fox dynamics and concomitant shifts in fluctuation patterns were observed. Our statistical analyses also revealed that the spatial progressive spread of mange mites was mirrored in the autocovariate structures of red fox populations progressively exposed to sarcoptic mange. PMID:10819147

Forchhammer, M C; Asferg, T

2000-04-22

130

Persistence of invading gypsy moth populations in the United States.  

PubMed

Exotic invasive species are a mounting threat to native biodiversity, and their effects are gaining more public attention as each new species is detected. Equally important are the dynamics of exotic invasives that are previously well established. While the literature reports many examples of the ability of a newly arrived exotic invader to persist prior to detection and population growth, we focused on the persistence dynamics of an established invader, the European gypsy moth (Lymantria dispar) in the United States. The spread of gypsy moth is largely thought to be the result of the growth and coalescence of isolated colonies in a transition zone ahead of the generally infested area. One important question is thus the ability of these isolated colonies to persist when subject to Allee effects and inimical stochastic events. We analyzed the US gypsy moth survey data and identified isolated colonies of gypsy moth using the local indicator of spatial autocorrelation. We then determined region-specific probabilities of colony persistence given the population abundance in the previous year and its relationship to a suite of ecological factors. We observed that colonies in Wisconsin, US, were significantly more likely to persist in the following year than in other geographic regions of the transition zone, and in all regions, the abundance of preferred host tree species and land use category did not appear to influence persistence. We propose that differences in region-specific rates of persistence may be attributed to Allee effects that are differentially expressed in space, and that the inclusion of geographically varying Allee effects into colony-invasion models may provide an improved paradigm for addressing the establishment and spread of gypsy moth and other invasive exotic species. PMID:16341893

Whitmire, Stefanie L; Tobin, Patrick C

2006-03-01

131

A construction of Killing spinors on Sn  

Microsoft Academic Search

We derive simple general expressions for the explicit Killing spinors on the n-sphere, for arbitrary n. Using these results we also construct the Killing spinors on various AdS×Sphere supergravity backgrounds, including AdS5×S5, AdS4×S7, and AdS7×S4. In addition, we extend previous results to obtain the Killing spinors on the hyperbolic spaces Hn.

H. Lü; C. N. Pope; J. Rahmfeld

1999-01-01

132

Timelike Killing spinors in seven dimensions  

E-print Network

We employ the G-structure formalism to study supersymmetric solutions of minimal and SU(2) gauged supergravities in seven dimensions admitting Killing spinors with associated timelike Killing vector. The most general such Killing spinor defines an 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 sixteen supersymmetries. Using our general supersymmetric ansatz we obtain numerous new solutions, including squashed or deformed AdS solutions of the gauged theory, and a large class of Godel-like solutions with closed timelike curves.

Marco Cariglia; Oisin A. P. Mac Conamhna

2004-07-14

133

Timelike Killing spinors in seven dimensions  

NASA Astrophysics Data System (ADS)

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 Gödel-like solutions with closed timelike curves.

Cariglia, Marco; Conamhna, Oisín A.

2004-12-01

134

Timelike Killing spinors in seven dimensions  

SciTech Connect

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.

Cariglia, Marco; Conamhna, Oisin A.P. Mac [DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

2004-12-15

135

HOW INVADED IS INVADED?  

EPA Science Inventory

One thrust of invasion biology has been to compare the extent of invasion among communities and biogeographic regions. A problem with such comparisons has been the plethora of metrics used and the lack of standardization as to what data are incorporated into the metrics. One sour...

136

The killing consensus : homicide detectives, police that kill and organized crime in São Paulo, Brazil  

E-print Network

Policing is widely understood, empirically and theoretically, as a core function of the state. Much of the knowledge presumes that police are the only body that may kill and arbitrate killing, routinely and without retaliation ...

Willis, Graham Arthur Neill, 1979-

2013-01-01

137

Exotic plant species invade hot spots of native plant diversity  

USGS Publications Warehouse

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.

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

138

Killing vectors in plane HH spaces  

Microsoft Academic Search

Employing the spinorial approach to the structure of hyperheavens, we integrate completely the Killing vector equations for plane (case I) hyperheavens, reducing them to one master equation of an extremely plausible form. (In this process, optimally simple gauges are demonstrated for each Petrov type.) The mechanism of generating Ernst potentials by Killing vectors is then investigated, and explicit forms are

J. D. Finley; J. F. Pleban´ski

1978-01-01

139

Hypersurface homogeneous Killing spinor space-times  

E-print Network

I present a complete list of hypersurface homogeneous space-times admitting a non-null valence two Killing spinor, including a new class admitting only exceptional Killing tensors. A connection is established with the classification of locally rotationally symmetric or boost symmetric space-times.

Bergh, Norbert Van den

2014-01-01

140

Deformations of M-theory Killing superalgebras  

NASA Astrophysics Data System (ADS)

We classify the Lie superalgebra deformations of the Killing superalgebras of some M-theory backgrounds. We show that the Killing superalgebras of the Minkowski, Freund Rubin and M5-brane backgrounds are rigid, whereas the ones for the M-wave, the Kaluza Klein monopole and the M2-brane admit deformations, which we give explicitly.

Figueroa-O'Farrill, José

2007-10-01

141

Hypersurface homogeneous Killing spinor space-times  

E-print Network

I present a complete list of hypersurface homogeneous space-times admitting a non-null valence two Killing spinor, including a new class admitting only exceptional Killing tensors. A connection is established with the classification of locally rotationally symmetric or boost symmetric space-times.

Norbert Van den Bergh

2014-08-19

142

Pulpability of Beetle-Killed Spruce  

E-print Network

the value of beetle-killed spruce as pulpwood. The results showed that live and dead spruce wood canPulpability of Beetle-Killed Spruce United States Department of Agriculture Forest Service Forest- rated wood required the same or slightly less refining energy to achieve a certain level of freeness

Abubakr, Said

143

Seasonal variation in the size and abundance of the invading Bythotrephes in Harp Lake, Ontario, Canada  

Microsoft Academic Search

Bythotrephes invaded Harp Lake, Ontario, Canada, in the early 1990s. Here we describe seasonal changes in the size, abundance and life history of the invader. The weight of Bythotrephes could be accurately estimated (r2 =0.90) from the length of its body and the state of development of its brood, but substantial (22%) corrections for shrinkage in sugarformalin were required. The

Norman D. Yan; Trevor W. Pawson

1997-01-01

144

Phylogeny and provenance affect plant–soil feedbacks in invaded California grasslands  

Microsoft Academic Search

Plant-soil feedbacks can affect plant community dynamics by influencing processes of coexistence or invasion, or by maintaining alternate stable states. Darwin's naturalization hypothesis suggests that phylogenetic relatedness should be a critical factor governing such feedbacks in invaded communities but is rarely considered in soil feedback studies. We investigated the effects of soil biota from experimentally established native and invaded California

Angela J. Brandt; Eric W. Seabloom; Parviez R. Hosseini

2009-01-01

145

PCB breakdown by anaerobic microorganisms  

SciTech Connect

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.

Not Available

1989-03-01

146

Effect of glucocorticosteroids on the phagocytosis and intracellular killing by peritoneal macrophages.  

PubMed Central

The effect of hydrocortisone on the phagocytosis and intracellular killing by mouse peritoneal macrophages in vitro was studied by a method making it possible to measure these processes separately. The results showed that in vivo treatment with 15 mg of hydrocortisone acetate did not significantly decrease the phagocytosis of several bacterial species such as Staphylococcus albus, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa. The killing indexes of normal macrophages for the various microorganisms were found to be significantly different. This may indicate that the bactericidal mechanisms are not uniform for these bacteria. The effect of hydrocortisone on the intracellular killing was also variable. For Staphylococcus albus a normal killing index was found. For the other species of bacterial and for Candida albicans some decrease was found, but this was only significant for Salmonella typhimurium. It is concluded that a decrease host resistance due to glucocorticosterioid treatment is not caused by a direct effect of these drugs on the phagocytosis and intracellular killing by mononuclear phagocytes. PMID:811557

Zwet, T L; Thompson, J; Furth, R

1975-01-01

147

CONFORMAL KILLING SPINORS AND THE HOLONOMY PROBLEM IN LORENTZIAN GEOMETRY  

E-print Network

. Conformal Killing spinors give rise to conformal Killing vector fields and conformal Killing formsCONFORMAL KILLING SPINORS AND THE HOLONOMY PROBLEM IN LORENTZIAN GEOMETRY ­ A SURVEY OF NEW RESULTS ­ HELGA BAUM Abstract. This paper is a survey of recent results about conformal Killing spinors

Baum, Helga

148

CONFORMAL KILLING SPINORS AND THE HOLONOMY PROBLEM IN LORENTZIAN GEOMETRY  

E-print Network

. Conformal Killing spinors give rise to conformal Killing vector fields and conformal Killing formsCONFORMAL KILLING SPINORS AND THE HOLONOMY PROBLEM IN LORENTZIAN GEOMETRY -- A SURVEY OF NEW RESULTS -- HELGA BAUM # Abstract. This paper is a survey of recent results about conformal Killing spinors

Baum, Helga

149

GENERALIZED KILLING SPINORS ON SPHERES ANDREI MOROIANU, UWE SEMMELMANN  

E-print Network

GENERALIZED KILLING SPINORS ON SPHERES ANDREI MOROIANU, UWE SEMMELMANN Abstract. We study generalized Killing spinors on round spheres Sn . We show that on the standard sphere S8 any generalized Killing spinor has to be an ordinary Killing spinor. Moreover we classify generalized Killing spinors

Semmelmann, Uwe

150

Dieldrin: Degradation by Soil Microorganisms  

Microsoft Academic Search

An attempt was made to discover microorganisms that degrade dieldrin, an extremely stable chlorinated hydrocarbon insecticide. Examination of more than 500 isolates from soil that had been heavily contaminated with various insecticides revealed the existence of a few microbes that are very active in degrading this compound to various metabolites.

F. Matsumura; G. M. Boush

1967-01-01

151

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...

152

Intergenomic Arms Races: Detection of a Nuclear Rescue Gene of Male-Killing in a Ladybird  

PubMed Central

Many species of arthropod are infected by deleterious inherited micro-organisms. Typically these micro-organisms are inherited maternally. Consequently, some, particularly bacteria of the genus Wolbachia, employ a variety of strategies that favour female over male hosts. These strategies include feminisation, induction of parthenogenesis and male-killing. These strategies result in female biased sex ratios in host populations, which lead to selection for host factors that promote male production. In addition, the intra-genomic conflict produced by the difference in transmission of these cytoplasmic endosymbionts and nuclear factors will impose a pressure favouring nuclear factors that suppress the effects of the symbiont. During investigations of the diversity of male-killing bacteria in ladybirds (Coccinellidae), unexpected patterns of vertical transmission of a newly discovered male-killing taxon were observed in the ladybird Cheilomenes sexmaculata. Initial analysis suggested that the expression of the bacterial male-killing trait varies according to the male(s) a female has mated with. By swapping males between females, a male influence on the expression of the male-killing trait was confirmed. Experiments were then performed to determine the nature of the interaction. These studies showed that a single dominant allele, which rescues male progeny of infected females from the pathological effect of the male-killer, exists in this species. The gene shows typical Mendelian autosomal inheritance and is expressed irrespective of the parent from which it is inherited. Presence of the rescue gene in either parent does not significantly affect the inheritance of the symbiont. We conclude that C. sexmaculata is host to a male-killing ?-proteobacterium. Further, this beetle is polymorphic for a nuclear gene, the dominant allele of which rescues infected males from the pathogenic effects of the male-killing agent. These findings represent the first reported case of a nuclear suppressor of male-killing in a ladybird. They are considered in regard to sex ratio and intra-genomic conflict theories, and models of the evolutionary dynamics and distribution of inherited symbionts. PMID:20628578

Majerus, Tamsin M. O.

2010-01-01

153

Killing machines: three pore-forming proteins of the immune system.  

PubMed

The evolution of early multicellular eukaryotes 400-500 million years ago required a defensive strategy against microbial invasion. Pore-forming proteins containing the membrane-attack-complex-perforin (MACPF) domain were selected as the most efficient means to destroy bacteria or virally infected cells. The mechanism of pore formation by the MACPF domain is distinctive in that pore formation is purely physical and unspecific. The MACPF domain polymerizes, refolds, and inserts itself into bilayer membranes or bacterial outer cell walls. The displacement of surface lipid/carbohydrate molecules by the polymerizing MACPF domain creates clusters of large, water-filled holes that destabilize the barrier function and provide access for additional anti-bacterial or anti-viral effectors to sensitive sites that complete the destruction of the invader via enzymatic or chemical attack. The highly efficient mechanism of anti-microbial defense by a combined physical and chemical strategy using pore-forming MACPF-proteins has been retargeted during evolution of vertebrates and mammals for three purposes: (1) to kill extracellular bacteria C9/polyC9 evolved in conjunction with complement, (2) to kill virus infected and cancer cells perforin-1/polyperforin-1 CTL evolved targeted by NK and CTL, and (3) to kill intracellular bacteria transmembrane perforin-2/putative polyperforin-2 evolved targeted by phagocytic and nonphagocytic cells. Our laboratory has been involved in the discovery and description of each of the three pore-formers that will be reviewed here. PMID:24293008

McCormack, Ryan; de Armas, Lesley; Shiratsuchi, Motoaki; Podack, Eckhard R

2013-12-01

154

Gauge theories on sphere and Killing vectors  

NASA Astrophysics Data System (ADS)

We provide a general method for studying manifestly O( n+1) covariant formulation of p-form gauge theories by stereographically projecting these theories, defined in flat Euclidean space, onto the surface of a hypersphere. The gauge fields in the two descriptions are mapped by conformal Killing vectors while conformal Killing spinors are necessary for the matter fields, allowing for a very transparent analysis and compact presentation of results. General expressions for these Killing vectors and spinors are given. The familiar results for a vector gauge theory are reproduced.

Banerjee, Rabin

2004-05-01

155

Grassland invader responses to realistic changes in native species richness.  

PubMed

The importance of species richness for repelling exotic plant invasions varies from ecosystem to ecosystem. Thus, in order to prioritize conservation objectives, it is critical to identify those ecosystems where decreasing richness will most greatly magnify invasion risks. Our goal was to determine if invasion risks greatly increase in response to common reductions in grassland species richness. We imposed treatments that mimic management-induced reductions in grassland species richness (i.e., removal of shallow- and/or deep-rooted forbs and/or grasses and/or cryptogam layers). Then we introduced and monitored the performance of a notorious invasive species (i.e., Centaurea maculosa). We found that, on a per-gram-of-biomass basis, each resident plant group similarly suppressed invader growth. Hence, with respect to preventing C. maculosa invasions, maintaining overall productivity is probably more important than maintaining the productivity of particular plant groups or species. But at the sites we studied, all plant groups may be needed to maintain overall productivity because removing forbs decreased overall productivity in two of three years. Alternatively, removing forbs increased productivity in another year, and this led us to posit that removing forbs may inflate the temporal productivity variance as opposed to greatly affecting time-averaged productivity. In either case, overall productivity responses to single plant group removals were inconsistent and fairly modest, and only when all plant groups were removed did C. maculosa growth increase substantially over a no-removal treatment. As such, it seems that intense disturbances (e.g., prolonged drought, overgrazing) that deplete multiple plant groups may often be a prerequisite for C. maculosa invasion. PMID:17913143

Rinella, Matthew J; Pokorny, Monica L; Rekaya, Romdhane

2007-09-01

156

Interaction of Herbicides and Soil Microorganisms.  

National Technical Information Service (NTIS)

The introduction of microorganisms with specific degradative capacities into the soil was shown to be a possible means of ridding the soil of contaminating chemicals. An investigation of the interactions of soil microorganisms and several groups of herbic...

1971-01-01

157

Killing Initial Data on spacelike conformal boundaries  

E-print Network

We analyze Killing Initial Data on Cauchy surfaces in conformally rescaled vacuum space-times satisfying Friedrich's conformal field equations. As an application, we derive the KID equations on a spacelike $\\mathcal{J}^-$.

Tim-Torben Paetz

2014-03-11

158

The Geometry of D=11 Killing Spinors  

E-print Network

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)\\ltimes R^8)x 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.

Jerome P. Gauntlett; Stathis Pakis

2002-12-02

159

The geometry of D = 11 Killing spinors  

NASA Astrophysics Data System (ADS)

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.

Gauntlett, Jerome P.; Pakis, Stathis

2003-04-01

160

Homogeneous Killing spinor space-times  

E-print Network

A classification of Petrov type D Killing spinor space-times admitting a homogeneous conformal representant is presented. For each class a canonical line-element is constructed and a physical interpretation of its conformal members is discussed.

Norbert Van den Bergh

2011-08-11

161

Killing spinors, supersymmetries and rotating intersecting branes  

Microsoft Academic Search

I review a recently proposed method for determining the symmetry superalgebra\\u000aof a supergravity configuration from its Killing spinors, and its application\\u000ato the `near-horizon' limits of various rotating and intersecting branes.

P. K. Townsend

1999-01-01

162

TWISTOR AND KILLING SPINORS IN LORENTZIAN GEOMETRY  

E-print Network

SPINORS IN LORENTZIAN GEOMETRY par. _ This paper is a survey about recent results concerning twistor and Killing spinors on Lorentzian. After some basic facts about twistor spinors we explain a relation between Lorentzian twist* *or

Baum, Helga

163

Toxicity of paraquat to microorganisms.  

PubMed

The biochemical response of the microorganisms Lipomyces starkeyi (Lod & Rij), Escherichia coli K-12 W3110, Bacillus subtilis 168 (Marburg) and Pseudomonas sp. strain TTO1 to the presence of growth-inhibitory concentrations of paraquat was studied. Paraquat was added to each culture at a concentration previously determined to reduce the culture growth rate by up to 50%. The changes in activity of a number of enzymes previously shown to be associated with the defense of the mammalian system against the action of paraquat were studied. While the response of E. coli was in agreement with that found in other studies of this microorganism and supports a commonly accepted mechanism for paraquat toxicity, the results obtained with L. starkeyi, B. subtilis, and Pseudomonas sp. strain TTO1 suggest that other mechanisms exist for protection against the toxicity of paraquat. PMID:3098166

Carr, R J; Bilton, R F; Atkinson, T

1986-11-01

164

Toxicity of paraquat to microorganisms.  

PubMed Central

The biochemical response of the microorganisms Lipomyces starkeyi (Lod & Rij), Escherichia coli K-12 W3110, Bacillus subtilis 168 (Marburg) and Pseudomonas sp. strain TTO1 to the presence of growth-inhibitory concentrations of paraquat was studied. Paraquat was added to each culture at a concentration previously determined to reduce the culture growth rate by up to 50%. The changes in activity of a number of enzymes previously shown to be associated with the defense of the mammalian system against the action of paraquat were studied. While the response of E. coli was in agreement with that found in other studies of this microorganism and supports a commonly accepted mechanism for paraquat toxicity, the results obtained with L. starkeyi, B. subtilis, and Pseudomonas sp. strain TTO1 suggest that other mechanisms exist for protection against the toxicity of paraquat. PMID:3098166

Carr, R J; Bilton, R F; Atkinson, T

1986-01-01

165

Mechanisms of halotolerance in microorganisms.  

PubMed

Microorganisms have the ability to adapt to a wide range of NaCl concentrations. In general the NaCl tolerance shown by microbes far exceeds the salt tolerance of any other organism, procryote or eukaryote. There are at least three mechanisms available for adaptation to different salt concentrations. The first would be a passive one in which the cytoplasmic ion content would always equal that in the medium. A second mechanism which is used by many organisms involves concentrating compatible solutes to create an osmotic balance between the cytoplasm and the external environment. The third mechanism involves changing the cell physiology to control the movement of water allowing the cell to exist with an ionically dilute cytoplasm. This article will review the major developments and discuss the implications of increasing knowledge about salt tolerance in microorganisms. PMID:3308318

Vreeland, R H

1987-01-01

166

Phosphate Biomineralization of Cambrian Microorganisms  

NASA Technical Reports Server (NTRS)

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.

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

1998-01-01

167

Spinor methods in conformal Killing transport  

Microsoft Academic Search

The equations of conformal Killing transport are discussed using tensor and spinor methods. It is shown that, in Minkowski space-time, the equations for a null conformal Killing vector ?a are completely determined by the corresponding spinor ?A and its covariant derivative, which defines a spinor pA'. In conformally flat space-time, the covariant derivative of pA' is also involved. Some applications

Kenza Dighton; Guildford County

1975-01-01

168

Gauge theories on sphere and Killing vectors  

Microsoft Academic Search

We provide a general method for studying manifestly O(n+1) covariant formulation of p-form gauge theories by stereographically projecting these theories, defined in flat Euclidean space, onto the surface of a hypersphere. The gauge fields in the two descriptions are mapped by conformal Killing vectors while conformal Killing spinors are necessary for the matter fields, allowing for a very transparent analysis

Rabin Banerjee

2004-01-01

169

Killing Spinor Equations from Nonlinear Realisations  

E-print Network

Starting from a nonlinear realisation of eleven dimensional supergravity based on the group G11, whose generators appear as low level generators of E11, we present a super extended algebra, which leads to a covariant derivative of spinors identical to the Killing spinor equation of this theory. A similar construction leads to the Killing spinor equation of N=1 pure supergravity in ten dimensions.

Andre Miemiec; Igor Schnakenburg

2004-04-26

170

Killing spinor equations from nonlinear realisations  

Microsoft Academic Search

Starting from a nonlinear realisation of eleven-dimensional supergravity based on the group G11, whose generators appear as low level generators of E11, we present a super extended algebra, which leads to a covariant derivative of spinors identical to the Killing spinor equation of this theory. A similar construction leads to the Killing spinor equation of N=1 pure supergravity in ten

André Miemiec; Igor Schnakenburg

2004-01-01

171

Killing spinors for the bosonic string  

NASA Astrophysics Data System (ADS)

We obtain the effective action for the bosonic string with arbitrary Yang-Mills fields, up to the ?' order, in general dimensions. The form of the action is determined by the requirement that the action admit well-defined Killing spinor equations, whose projected integrability conditions give rise to the full set of equations of motion. The success of the construction suggests that the hidden "pseudo-supersymmetry" associated with the Killing spinor equations may be a property of the bosonic string itself.

Lü, H.; Wang, Zhao-Long

2012-03-01

172

Dangerously antisocial youths who kill their parents  

Microsoft Academic Search

Adolescent parricide offenders are typically presented in the popular and professional literature as prosocial youths in fear\\u000a of their lives, often killing to protect themselves or others from death or serious physical injury or to end the chronic\\u000a abuse they and other family members suffer. There are, however, dangerously antisocial youths who kill their parents for selfish,\\u000a instrumental reasons.\\u000a \\u000a The

Kathleen M. Heide

1995-01-01

173

Biology 2004: Diversity II Microorganisms and Plants  

E-print Network

Biology 2004: Diversity II Microorganisms and Plants Winter 2011 Class description: Microbes were in when her door is open; E-mail: Arunika.Gunawardena@dal.ca Microorganisms- Dr. Alastair Simpson ; Office of the microorganisms section. These will be made available to you later in the term. Course Website: The Course Website

Adl, Sina

174

Original article Microorganisms associated with pollen,  

E-print Network

Original article Microorganisms associated with pollen, honey, and brood provisions in the nest identified. Few other microorganisms were found. These bacteria produced a variety of enzymes including es and fatty acids to inhibit competing microorganisms which could cause spoilage of stored food, particularly

Paris-Sud XI, Université de

175

Selective accumulation of heavy metals by microorganisms  

Microsoft Academic Search

An investigation of the removal and recovery of urnnium from aqueous systems using microbial biomass has been described previously (Nakajima et al. 1982). To establish which microorganisms accumulate the most uranium, we extended our investigation of uranium uptake to 83 species of microorganisms, 32 bacteria, 15 yeasts, 16 fungi and 20 actinomycetes. Of these 83 species of microorganisms tested, extremely

Akira Nakajima; Takashi Sakaguchi

1986-01-01

176

Predatory Microorganisms Would Help Reclaim Water  

NASA Technical Reports Server (NTRS)

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.

Benjaminson, Morris A.; Lehrer, Stanley

1995-01-01

177

Emerging contaminants and microorganisms into the environment  

E-print Network

Workshop Emerging contaminants and microorganisms into the environment: contamination pathways, University of Brescia (Italy) 14:30 14:55 16:15 15:50 15:20 Workshop Emerging contaminants and microorganisms, endocrine disruptors etc.) and pathogen microorganisms from diffuse and point sources, resulted in a high

Costagliola, Gennaro

178

Wolbachia, sex ratio bias and apparent male killing in the harlequin beetle riding pseudoscorpion.  

PubMed

Bacterial endosymbionts that manipulate host reproduction are now known to be widespread in insects and other arthropods. Since they inhabit the cytoplasm and are maternally inherited, these microorganisms can enhance their fitness by biasing host sex ratio in favour of females. At its most extreme, sex ratio manipulation may be achieved by killing male embryos, as occurs in a number of insect species. Here, we provide evidence for the first case of male killing by a tetracycline-sensitive microbe in pseudoscorpions. Using a combination of inheritance studies, antibiotic treatment and molecular assays, we show that a new strain of Wolbachia is associated with extreme female bias in the pseudoscorpion, Cordylochernes scorpioides. In a highly female-biased line, sex ratio distortion was maternally inherited, and occurred in conjunction with a high rate of spontaneous abortion and low reproductive success. Antibiotic treatment cured females of the Wolbachia infection, restored offspring sex ratio to 1:1, and significantly enhanced female reproductive success. The discovery of apparent male-killing in C. scorpioides is of interest because pseudoscorpions are viviparous. Theory predicts that male killing should be favoured, if male death enhances the fitness of infected female siblings. In a live-bearing host, reallocation of maternal resources from dead male embryos to their sisters provides a direct, physiological mechanism through which fitness compensation could favour male killing by cellular endosymbionts. Our results suggest, however, that fitness compensation and the spread of male-killing endosymbionts may be undermined by a high rate of spontaneous abortion in infected females of this viviparous arthropod. PMID:15931253

Zeh, D W; Zeh, J A; Bonilla, M M

2005-07-01

179

SYNTHESIS Invisible invaders: non-pathogenic invasive microbes in aquatic and terrestrial ecosystems  

E-print Network

, invasive species, invasiveness, microbial biogeography, protists, symbiotic, traits. Ecology Letters (2010REVIEW AND SYNTHESIS Invisible invaders: non-pathogenic invasive microbes in aquatic and terrestrial ecosystems Elena Litchman* Kellogg Biological Station, Michigan State University, Hickory Corners

180

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...

181

Clonal integration facilitates the proliferation of smooth brome clones invading northern fescue prairies  

E-print Network

of successful invaders of natural areas, facilitates the proliferation of Bromus inermis (smooth brome Invasive plant Á Physiological integration Á Bromus inermis Á Native prairie Á Clonal growth Introduction

Kenkel, Norm

182

ORIGINAL PAPER Invading with biological weapons: the role of shared disease  

E-print Network

ORIGINAL PAPER Invading with biological weapons: the role of shared disease in ecological invasion. This scenario where the parasites acts as a "biological weapon" has been Theor Ecol (2009) 2:53­66 DOI 10.1007/s

Sherratt, Jonathan A.

183

Plasticity and Genetic Diversity May Allow Saltcedar to Invade Cold Climates in North America  

Microsoft Academic Search

Two major mechanisms have been proposed to explain the ability of intro- duced populations to colonize over large habitat gradients, despite significant population bottlenecks during introduction: (1) Broad environmental tolerance—successful invaders possess life history traits that confer superior colonizing ability and\\/or phenotypic plasticity, allowing acclimation to a wide range of habitats. (2) Local adaptation—successful invaders rapidly adapt to local selective

Jason P. Sexton; John K. McKay; Anna Sala

2002-01-01

184

Effects of a habitat-altering invader on nesting sparrows: An ecological trap?  

Microsoft Academic Search

Many invading species impact native species through predation, parasitism or competition, while others affect natives indirectly\\u000a by restructuring their habitat. How invasive plants affect native animals, and to what extent native animals respond to changes\\u000a in their habitat and the novel selection pressures that follow, is not well known. We investigated the impacts of a habitat-altering\\u000a invader, the Atlantic cordgrass

J. Cully Nordby; Andrew N. Cohen; Steven R. Beissinger

2009-01-01

185

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

PubMed

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

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

186

Biocidal activity of metalloacid-coated surfaces against multidrug-resistant microorganisms  

PubMed Central

Background The antimicrobial effects of a coating of molybdenum trioxide (MoO3) has been recently described. The metalloacid material produces oxonium ions (H3O+), which creates an acidic pH that is an effective, non specific antimicrobial. We determined the in vitro antimicrobial activity of molybdenum trioxide metalloacid-coated surfaces. Methods Metalloacid-coated and non-coated (control) surfaces were contaminated by exposing them for 15 minutes to microbial suspensions containing 105 cfu/mL. Eleven microorganisms responsible for nosocomial infections were tested: two Staphylococcus aureus strains (the hetero-vancomycin intermediate MRSA Mu50 strain and a ST80-PVL-producing MRSA strain); a vancomycin-resistant vanA Enterococcus faecium strain; three extended-spectrum beta-lactamase-producing Enterobacteriaceae strains; a MBL-producing Pseudomonas aeruginosa strain; a multidrug-resistant Acinetobacter baumannii strain; a toxin-producing Clostridium difficile strain; and two fungi (Candida albicans and Aspergillus fumigatus). The assay tested the ability of the coated surfaces to kill microorganisms. Results Against all non-sporulating microorganisms tested, metalloacid-coated surfaces exhibited significant antimicrobial activity relative to that of the control surfaces within two to six hours after contact with the microorganisms (p?Microorganism survival on the coated surfaces was greatly impaired, whereas microorganism survival on control surfaces remained substantial. Conclusions We suggest that, facing the continuing shedding of microorganisms in the vicinity of colonized or infected patients, the continuous biocidal effect of hydroxonium oxides against multidrug-resistant microorganisms may help limit environmental contamination between consecutive cleaning procedures. PMID:23148568

2012-01-01

187

Proteasomes Control Caspase-1 Activation in Anthrax Lethal Toxin-mediated Cell Killing*S  

E-print Network

Proteasomes Control Caspase-1 Activation in Anthrax Lethal Toxin-mediated Cell Killing*S Received York 10461 Activation of caspase-1 through the inflammasome protein Nalp1b controls anthrax lethal evidence of membrane impairment recovered upon the addition of MG132, mirroring the Boc-D-cmk response

Brojatsch, Jürgen

188

Integration without integration: New Killing spinor spacetimes  

NASA Astrophysics Data System (ADS)

Non-conformally flat spacetimes admitting a non-null two-index Killing spinor are investigated by means of the Geroch-Held-Penrose formalism. Claims appearing in the literature that such spacetimes are all explicitly known are incorrect. This was shown in [5] for the family where, in the canonical frame, the spin coefficients ? or ?, vanish. Here the general case with non-vanishing ?, ?, ? and ? is re-considered. It is shown that the construction in [4] hinges on the tacit assumption that certain integrability conditions hold, implying two algebraic relations for the spin coefficients and the components of the Ricci spinor. All (conformal classes of) spacetimes, in which one of these conditions is violated, are obtained by invariant integration. The resulting classes are each other's Sachs transform and are characterised by one free function. They admit in general no Killing vectors, but still admit a conformal gauge (different from the trivial unitary gauge) in which a Killing tensor exists.

Van den Bergh, Norbert

2010-05-01

189

Conformal Killing vectors in nonexpanding HH-spaces with ?  

NASA Astrophysics Data System (ADS)

The general structure of nonexpanding hyperheavenly spaces is presented. We find conformal Killing equations and their integrability conditions in spinorial formalism. The reduction of Killing equations to one master equation is also presented. We generalize the Killing problem on the case of a nonzero cosmological constant and a conformal Killing factor. Finally, an example of the complex [N]otimes[N] space with the conformal Killing vector is considered and the respective metric is explicitly given.

Chudecki, Adam

2010-10-01

190

Extracellular killing of inhaled pneumococci in rats  

SciTech Connect

Early clearance of inhaled Staphylococcus aureus is believed to be caused by phagocytosis by alveolar macrophages. In murine models inhaled pneumococci are cleared even more rapidly than S. aureus. Conventional opsonins appear to play no role in this clearance, and recently it has been shown that murine alveolar lining material contains free fatty acids and other soluble factors that are directly bactericidal for pneumococci. To determine whether non-phagocytic factors are involved in pneumococcal clearance, we compared the site of killing of inhaled pneumococci and S. aureus in rats using histologic methods and bronchoalveolar lavage. Spontaneous lysis of pneumococci was prevented by use of autolysin-defective pneumococci or by substitution of ethanolamine for choline in the cell wall. Histologic studies showed that the percent of inhaled staphylococci associated with alveolar macrophages always exceeded the percent of staphylococci cleared, whereas there was little association of pneumococci with macrophages during clearance. Analysis of the intracellular or extracellular location of iron 59 in bronchoalveolar lavage fluid of rats that had inhaled aerosols of /sup 59/Fe-labeled bacteria suggested that staphylococci were killed predominantly in macrophages and pneumococci in the extracellular space. When /sup 59/Fe-labeled pneumococci or staphylococci were ingested and killed by macrophages in vitro, the /sup 59/Fe remained with the macrophages, suggesting that the extracellular location of /sup 59/Fe during pneumococcal killing in vivo was not caused by rapid turnover of /sup 59/Fe in macrophages. Studies of the site of killing of inhaled type 25 pneumococci labeled exclusively in the cell wall with carbon 14-ethanolamine confirmed the results obtained with /sup 59/Fe-labeled pneumococci. Thus, early killing of inhaled pneumococci, unlike staphylococci, appears to take place outside of macrophages.

Coonrod, J.D.; Marple, S.; Holmes, G.P.; Rehm, S.R.

1987-12-01

191

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

NASA Astrophysics Data System (ADS)

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.

Oshima, Tairo; Moriya, Toshiyuki; Yoshii, Takahiro

192

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

PubMed Central

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

2010-01-01

193

Cytotoxic Killing and Immune Evasion by Repair  

NASA Astrophysics Data System (ADS)

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

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

2007-07-01

194

Timelike Killing Fields and Relativistic Statistical Mechanics  

E-print Network

For spacetimes with timelike Killing fields, we introduce a "Fermi-Walker-Killing" coordinate system and use it to prove a Liouville Theorem for an appropriate volume element of phase space for a statistical mechanical system of particles. We derive an exact relativistic formula for the Helmholtz free energy of an ideal gas and compare it, for a class of spacetimes, to its Newtonian analog, derived both independently and as the Newtonian limit of our formula. We also find the relativistic thermodynamic equation of state. Specific examples are given in Kerr spacetime.

David Klein; Peter Collas

2008-10-09

195

Killing Spinors for the Bosonic String  

E-print Network

We obtain the effective action for the bosonic string with arbitrary Yang-Mills fields, up to the \\alpha' order, in general dimensions. The form of the action is determined by the requirement that the action admit well-defined Killing spinor equations, whose projected integrability conditions give rise to the full set of equations of motion. The success of the construction suggests that the hidden "pseudo-supersymmetry" associated with the Killing spinor equations may be a property of the bosonic string itself.

Lu, H

2011-01-01

196

Killing Spinors for the Bosonic String  

E-print Network

We obtain the effective action for the bosonic string with arbitrary Yang-Mills fields, up to the \\alpha' order, in general dimensions. The form of the action is determined by the requirement that the action admit well-defined Killing spinor equations, whose projected integrability conditions give rise to the full set of equations of motion. The success of the construction suggests that the hidden "pseudo-supersymmetry" associated with the Killing spinor equations may be a property of the bosonic string itself.

H. Lu; Zhao-Long Wang

2011-06-08

197

Internet Resources on Genocide and Mass Killings  

NSDL National Science Digital Library

Internet Resources on Genocide and Mass Killings is an extensive compilation of primary materials and annotated links related to "twentieth-century genocidal and mass man-made killing occurrences." Divided into fifteen sections, subject coverage includes topics such as The Jewish Holocaust, War Crimes and Criminals, Yugoslavia and Kosovo, among others. Most of the original documents in the compilation have been uploaded to the site, facilitating navigation and research. Documents not residing at the site are linked via succinct annotations. The compilation is searchable and updated continuously by its creator Dr. Stuart D. Stein, Senior Lecturer in Sociology and Social Psychology at the University of West England.

198

Rapid Kill--Novel Endodontic Sealer and Enterococcus faecalis  

PubMed Central

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

Zaltsman, Nathan; Houri-Haddad, Yael; Abramovitz, Itzhak; Davidi, Michael Perez; Weiss, Ervin I.

2013-01-01

199

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

PubMed Central

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

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

2013-01-01

200

Can Vet Schools Teach without Killing Animals?  

ERIC Educational Resources Information Center

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…

Mangan, Katherine S.

2000-01-01

201

Oxidative killing of microbes by neutrophils  

Microsoft Academic Search

Neutrophils and other phagocytic leukocytes contain a phagocyte NADPH oxidase enzyme that generates superoxide after cell activation. Reactive oxygen species derived from superoxide, together with proteases liberated from the granules, are used to kill ingested microbes. Dysfunction of the phagocyte NADPH oxidase results in chronic granulomatous disease, with life-threatening infections.

Dirk Roos; Robin van Bruggen; Christof Meischl

2003-01-01

202

Methods of killing employed by psychotic parricides.  

PubMed

Lewis, et al. in 1998 showed that psychotic women are more likely to use a weapon than nonpsychotic women to kill their children. This study presents data concerning psychotic parricide. Analysis indicated that a higher percentage used a weapon (81% versus 36%) than psychotic filicide. Reasons for this difference are discussed. PMID:14650686

Marleau, Jacques D

2003-10-01

203

TWISTOR AND KILLING SPINORS IN LORENTZIAN GEOMETRY  

Microsoft Academic Search

This paper is a survey of recent results concerning twistor and Killing spinors on Lorentzian manifolds based on lectures given at CIRM, Luminy, in June 1999, and at ESI, Wien, in October 1999. After some basic facts about twistor spinors we explain a relation between Lorentzian twistor spinors with lightlike Dirac current and the Fefferman spaces of strictly pseudoconvex spin

Helga Baum

2000-01-01

204

Imaginary Killing spinors in Lorentzian geometry  

Microsoft Academic Search

We study the geometric structure of Lorentzian spin manifolds, which admit imaginary Killing spinors. The discussion is based on the cone construction and a normal form classification of skew-adjoint operators in signature (2,n-2). Derived geometries include Brinkmann spaces, Lorentzian Einstein-Sasaki spaces and certain warped product structures. Exceptional cases with decomposable holonomy of the cone are possible.

Felipe Leitner

2003-01-01

205

Killing Spinors for the Bosonic String  

Microsoft Academic Search

We obtain the effective action for the bosonic string with arbitrary Yang-Mills fields, up to the \\\\alpha' order, in general dimensions. The form of the action is determined by the requirement that the action admit well-defined Killing spinor equations, whose projected integrability conditions give rise to the full set of equations of motion. The success of the construction suggests that

H. Lu; Zhao-Long Wang

2011-01-01

206

Killing Spinors and Massless Spinor Fields  

Microsoft Academic Search

It is shown that in a space-time that admits a Killing spinor any solution of the Weyl or of the Maxwell equations can be used as a potential for another solution of the corresponding equation. Furthermore, it is shown that the new solution can be generated by a single component of the given one, which satisfies a decoupled equation. For

G. F. Torres del Castillo

1985-01-01

207

Killing spinors and SYM on curved spaces  

Microsoft Academic Search

We construct two families of globally supersymmetric counterparts of standard Poincaré supersymmetric SYM theories on curved space-times admitting Killing spinors, in all dimensions less than six and eight, respectively. The former differs from the standard theory only by mass terms for the fermions and scalars and modified supersymmetry transformation rules, the latter in addition has cubic Chern-Simons like couplings for

Matthias Blau; Abdus Salam

2000-01-01

208

Killing spinors for the bosonic string  

Microsoft Academic Search

We obtain the effective action for the bosonic string with arbitrary Yang-Mills fields, up to the ?? order, in general dimensions. The form of the action is determined by the requirement that the action admit well-defined Killing spinor equations, whose projected integrability conditions give rise to the full set of equations of motion. The success of the construction suggests that

H. Lü; Zhao-Long Wang

2012-01-01

209

New brane solutions from Killing spinor equations  

Microsoft Academic Search

In a recent paper, we have pointed out a relation between the Killing spinor and Einstein equations. Using this relation, new brane solutions of D=11 and D=10 type IIB supergravity theories are constructed. It is shown that in a brane solution, the flat world-volume directions, the smeared transverse directions and the sphere located at a fixed radial distance can be

Ali Kaya

2000-01-01

210

The Ultimate Buzz Kill Mosquito Control  

E-print Network

, ditches, and culverts free of weeds and trash so the water can drain properly. Change water in birdbaths adult mosquitoes will not hide there. Make sure ornamental ponds have fish that will feed on mosquito Bacillus thuringiensis israelensis (Bti) Mosquito Dunks Mosquito Quick Kill Granules NOT harmful to fish

Johnson, Eric E.

211

How to Make a Killing Jar  

NSDL National Science Digital Library

This Biodiversity Counts illustration shows students how to make a simple killing jar to preserve arthropods for further study. As the labeled drawing shows, all that's needed is a jar with a lid, tape for reinforcement, a few drops of ethyl acetate, and a paper towel.

212

School Shootings; Standards Kill Students and Society  

ERIC Educational Resources Information Center

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…

Angert, Betsy L.

2008-01-01

213

Mass killings and detection of impacts  

NASA Technical Reports Server (NTRS)

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.

Mclaren, Digby J.

1988-01-01

214

killed-virus influenza vaccine Polio vaccine  

E-print Network

killed-virus influenza vaccine Polio vaccine FluMist Thomas Francis, Jr. National Institutes of Michigan's Rackham Auditorium and watched Thomas Francis Jr. announce to the world that the polio vaccine petitioned to spend a year or two in Francis's lab. Indeed, Jonas Salk, developer of the Salk polio vac- cine

Shyy, Wei

215

Surveillance technology If looks could kill  

E-print Network

Surveillance technology If looks could kill Oct 23rd 2008 From The Economist print edition Security experts reckon the latest technology can detect hostile intentions before something bad happens. Unless several times over the course of a few days without getting on a train. Is that suspicious? Possibly

Davis, James W.

216

A combined microfluidic/dielectrophoretic microorganism concentrator  

E-print Network

This thesis presents the development of a high-throughput microfluidic microorganism concentrator for pathogen detection applications. Interdigitated electrodes lining the bottom of the channel use positive dielectrophoretic ...

Gadish, Nitzan

2005-01-01

217

of pattern formation by swimming microorgan-isms. J. Protozool. 22: 296-306.  

E-print Network

130 Notes of pattern formation by swimming microorgan- isms. J. Protozool. 22: 296-306. MACNAB, R suspension ofgyrotactic micro-organisms. J. Fluid Mech. 195: 223-237. RICHARDSON, L.L.,C. AGUILAR,AND K

218

Life history variation in a temperate plant invader, Verbascum thapsus along a tropical elevational gradient in Hawaii  

Microsoft Academic Search

Few studies have examined the life history of temperate plant invaders in the tropics. Temperate invaders that utilize seasonal\\u000a cues to influence their life histories may be expected to behave differently in the tropics. This study examined variation\\u000a in life history in an invading temperate weed, Verbascum thapsus, across an elevation gradient (1,690–2,720 m) along the montane and subalpine slopes of

Shahin AnsariCurtis; Curtis C. Daehler

2010-01-01

219

GREATER MALE FITNESS OF A RARE INVADER (SPARTINA ALTERNIFLORA ,P OACEAE) THREATENS A COMMON NATIVE (SPARTINA FOLIOSA) WITH HYBRIDIZATION1  

Microsoft Academic Search

Hybridization with abundant invaders is a well-known threat to rare native species. Our study addresses mechanisms of hybridization between a rare invader, smooth cordgrass (Spartina alterniflora) and the common native California cordgrass (S. foliosa) in the salt marshes of San Francisco Bay. These species are wind-pollinated and flower in summer. The invader produced 21-fold the viable pollen of the native,

CARINA K. ANTTILA; CURTIS C. DAEHLER; NATHAN E. RANK; DONALD R. STRONG

220

Degradation of polychlorinated biphenyls by microorganisms  

SciTech Connect

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)

Yagi, O.; Sudo, R.

1980-05-01

221

Functional Microorganisms for Functional Food Quality  

Microsoft Academic Search

Functional microorganisms and health benefits represent a binomial with great potential for fermented functional foods. The health benefits of fermented functional foods are expressed either directly through the interactions of ingested live microorganisms with the host (probiotic effect) or indirectly as the result of the ingestion of microbial metabolites synthesized during fermentation (biogenic effect). Since the importance of high viability

M. Gobbetti; R. Di Cagno; M. De Angelis

2010-01-01

222

Aerobic and Anaerobic Biodegradation Potentials of Microorganisms  

Microsoft Academic Search

Microorganisms represent essential components of the global carbon cycle. In addition, it appears that most xenobiotic industrial chemicals can be degraded by microorganisms, either by a combination of cometabolic steps, often yielding partial degradation, or by serving as growth substrate which is accompanied by mineralization of at least part of the molecule. Using a number of examples, including aromatic, chloroaromatic,

Walter Reineke

223

Antimicrobial Activity of Propolis on Oral Microorganisms  

Microsoft Academic Search

.   Formation of dental caries is caused by the colonization and accumulation of oral microorganisms and extracellular polysaccharides\\u000a that are synthesized from sucrose by glucosyltransferase of Streptococcus mutans. The production of glucosyltransferase from oral microorganisms was attempted, and it was found that Streptococcus mutans produced highest activity of the enzyme. Ethanolic extracts of propolis (EEP) were examined whether EEP inhibit

Yong K. Park; Michel H. Koo; José A. S. Abreu; Masaharu Ikegaki; Jaime A. Cury; Pedro L. Rosalen

1998-01-01

224

Microorganisms detected by enzyme-catalyzed reaction  

NASA Technical Reports Server (NTRS)

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.

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

1966-01-01

225

Underground blowout killed with quick snubbing operation  

SciTech Connect

A shallow underground blowout off the island of Trinidad required quick action and the importing of snubbing equipment to kill the well and avert cratering the sea floor beneath the platform. The blowout was controlled in 16 days. The blowout at Trintomar's Pelican platform on the east coast of Trinidad posed a most challenging well control problem. Most of the service companies with equipment to control the well were not available in this relatively remote area. Because of the high gas and condensate flow rates and high pressure, the blowout at the Pelican platform had the potential to destroy the entire platform, endanger the lives of many crew members, result in the loss of natural resources, and interrupt the supply of natural gas to the island of Trinidad. The paper discusses the Pelican platform, the underground blowout, temperature survey, the kill plan, and snubbing operations.

Grace, R. (Grace, Shursen, Moore and Associates Inc., Amarillo, TX (United States)); Stanislaus, G. (Trinmar Ltd., Point Fortin (Trinidad and Tobago)); Cudd, B. (Cudd Pressure Control, Woodward, OK (United States))

1993-10-18

226

Conformal Killing Tensors and covariant Hamiltonian Dynamics  

E-print Network

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 H\\'enon-Heiles and Holt systems, respectively, providing us with Killing tensors of rank that ranges from one to six.

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

2014-04-13

227

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

228

A More Effective Kill Shot through Proper Forehand.  

ERIC Educational Resources Information Center

One of the most important skills for the beginning racquetball player to acquire is a high velocity kill shot. Factors necessary in making a good kill shot are described, and drills for teaching this skill are presented. (JN)

Stoner, Clarence

1981-01-01

229

Parallel and Killing Spinors on Spin c Manifolds  

Microsoft Academic Search

:  We describe all simply connected Spinc manifolds carrying parallel and real Killing spinors. In particular we show that every Sasakian manifold (not necessarily\\u000a Einstein) carries a canonical Spinc structure with Killing spinors.

Andrei Moroianu

1997-01-01

230

GENERALIZED KILLING SPINORS ON EINSTEIN MANIFOLDS ANDREI MOROIANU, UWE SEMMELMANN  

E-print Network

GENERALIZED KILLING SPINORS ON EINSTEIN MANIFOLDS ANDREI MOROIANU, UWE SEMMELMANN Abstract. We study generalized Killing spinors on compact Einstein manifolds with posi- tive scalar curvature. This problem is related to the existence compact Einstein hypersurfaces in manifolds with parallel spinors

Semmelmann, Uwe

231

9 CFR 113.206 - Wart Vaccine, Killed Virus.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart...

2010-01-01

232

9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

... false Pseudorabies Vaccine, Killed Virus. 113.213 Section 113.213 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.213...

2013-01-01

233

9 CFR 113.206 - Wart Vaccine, Killed Virus.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart...

2012-01-01

234

9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.  

... Feline Calicivirus Vaccine, Killed Virus. 113.210 Section 113.210 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.210 Feline...

2014-01-01

235

9 CFR 113.206 - Wart Vaccine, Killed Virus.  

...2014-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart...

2014-01-01

236

9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.  

... false Pseudorabies Vaccine, Killed Virus. 113.213 Section 113.213 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.213...

2014-01-01

237

9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.  

Code of Federal Regulations, 2012 CFR

... Feline Calicivirus Vaccine, Killed Virus. 113.210 Section 113.210 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.210 Feline...

2012-01-01

238

9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2011 CFR

...Avian Encephalomyelitis Vaccine, Killed Virus. 113.208 Section 113.208 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.208 Avian...

2011-01-01

239

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

... false Parvovirus Vaccine, Killed Virus (Canine). 113.214 Section 113...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.214 Parvovirus...

2014-01-01

240

9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2012 CFR

...Avian Encephalomyelitis Vaccine, Killed Virus. 113.208 Section 113.208 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.208 Avian...

2012-01-01

241

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

Code of Federal Regulations, 2011 CFR

... false Parvovirus Vaccine, Killed Virus (Canine). 113.214 Section 113...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.214 Parvovirus...

2011-01-01

242

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

Code of Federal Regulations, 2013 CFR

... false Parvovirus Vaccine, Killed Virus (Canine). 113.214 Section 113...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.214 Parvovirus...

2013-01-01

243

9 CFR 113.206 - Wart Vaccine, Killed Virus.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart...

2011-01-01

244

9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.  

Code of Federal Regulations, 2011 CFR

... Feline Calicivirus Vaccine, Killed Virus. 113.210 Section 113.210 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.210 Feline...

2011-01-01

245

9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.  

...Avian Encephalomyelitis Vaccine, Killed Virus. 113.208 Section 113.208 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.208 Avian...

2014-01-01

246

9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.  

Code of Federal Regulations, 2011 CFR

... false Pseudorabies Vaccine, Killed Virus. 113.213 Section 113.213 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.213...

2011-01-01

247

9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2010 CFR

...Feline Rhinotracheitis Vaccine, Killed Virus. 113.211 Section 113.211 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.211 Feline...

2010-01-01

248

9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

...Avian Encephalomyelitis Vaccine, Killed Virus. 113.208 Section 113.208 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.208 Avian...

2013-01-01

249

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

Code of Federal Regulations, 2012 CFR

... false Parvovirus Vaccine, Killed Virus (Canine). 113.214 Section 113...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.214 Parvovirus...

2012-01-01

250

9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2012 CFR

...Feline Rhinotracheitis Vaccine, Killed Virus. 113.211 Section 113.211 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.211 Feline...

2012-01-01

251

9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.  

Code of Federal Regulations, 2010 CFR

... Feline Calicivirus Vaccine, Killed Virus. 113.210 Section 113.210 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.210 Feline...

2010-01-01

252

9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

... Feline Calicivirus Vaccine, Killed Virus. 113.210 Section 113.210 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.210 Feline...

2013-01-01

253

9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2010 CFR

...Avian Encephalomyelitis Vaccine, Killed Virus. 113.208 Section 113.208 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.208 Avian...

2010-01-01

254

9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2011 CFR

...Feline Rhinotracheitis Vaccine, Killed Virus. 113.211 Section 113.211 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.211 Feline...

2011-01-01

255

9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

...Feline Rhinotracheitis Vaccine, Killed Virus. 113.211 Section 113.211 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.211 Feline...

2013-01-01

256

9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.  

Code of Federal Regulations, 2012 CFR

... false Pseudorabies Vaccine, Killed Virus. 113.213 Section 113.213 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.213...

2012-01-01

257

9 CFR 113.206 - Wart Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart...

2013-01-01

258

9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.  

...Feline Rhinotracheitis Vaccine, Killed Virus. 113.211 Section 113.211 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.211 Feline...

2014-01-01

259

AGE AND CONDITION OF DEER KILLED BY PREDATORS AND AUTOMOBILES  

E-print Network

) and white-tailed deer (0. uirginianus) killed by mountain lions (Felti concolor), coyotes (Cants Zatrans and white-tailed deer killed by mountain lions, coyotes, and automobiles from December through March, 1969

Harris, Richard B.

260

Systems Biology of Industrial Microorganisms  

NASA Astrophysics Data System (ADS)

The field of industrial biotechnology is expanding rapidly as the chemical industry is looking towards more sustainable production of chemicals that can be used as fuels or building blocks for production of solvents and materials. In connection with the development of sustainable bioprocesses, it is a major challenge to design and develop efficient cell factories that can ensure cost efficient conversion of the raw material into the chemical of interest. This is achieved through metabolic engineering, where the metabolism of the cell factory is engineered such that there is an efficient conversion of sugars, the typical raw materials in the fermentation industry, into the desired product. However, engineering of cellular metabolism is often challenging due to the complex regulation that has evolved in connection with adaptation of the different microorganisms to their ecological niches. In order to map these regulatory structures and further de-regulate them, as well as identify ingenious metabolic engineering strategies that full-fill mass balance constraints, tools from systems biology can be applied. This involves both high-throughput analysis tools like transcriptome, proteome and metabolome analysis, as well as the use of mathematical modeling to simulate the phenotypes resulting from the different metabolic engineering strategies. It is in fact expected that systems biology may substantially improve the process of cell factory development, and we therefore propose the term Industrial Systems Biology for how systems biology will enhance the development of industrial biotechnology for sustainable chemical production.

Papini, Marta; Salazar, Margarita; Nielsen, Jens

261

Integration without integration: New Killing spinor spacetimes  

Microsoft Academic Search

Non-conformally flat spacetimes admitting a non-null two-index Killing spinor are investigated by means of the Geroch-Held-Penrose formalism. Claims appearing in the literature that such spacetimes are all explicitly known are incorrect. This was shown in [5] for the family where, in the canonical frame, the spin coefficients rho or mu, vanish. Here the general case with non-vanishing rho, mu, pi

Norbert Van den Bergh

2010-01-01

262

Integration without integration: New Killing spinor spacetimes  

Microsoft Academic Search

Non-conformally flat spacetimes admitting a non-null two-index Killing spinor are investigated by means of the Geroch-Held-Penrose formalism. Claims appearing in the literature that such spacetimes are all explicitly known are incorrect. This was shown in [5] for the family where, in the canonical frame, the spin coefficients ? or ?, vanish. Here the general case with non-vanishing ?, ?, ?

Norbert Van den Bergh

2010-01-01

263

Generalized Killing spinors in dimension 5  

Microsoft Academic Search

We study the intrinsic geometry of hypersurfaces in Calabi-Yau manifolds of\\u000areal dimension 6 and, more generally, SU(2)-structures on 5-manifolds defined\\u000aby a generalized Killing spinor. We prove that in the real analytic case, such\\u000aa 5-manifold can be isometrically embedded as a hypersurface in a Calabi-Yau\\u000amanifold in a natural way. We classify nilmanifolds carrying invariant\\u000astructures of this

Diego Conti; Simon Salamon

2007-01-01

264

Killing spinors of some supergravity solutions  

Microsoft Academic Search

We compute explicitly the Killing spinors of some ten dimensional supergravity solutions. We begin with a 10d metric of the form IR1,3 × Y6, where Y6 is either the singular conifold or any of its resolutions. Then, we move on to the Klebanov-Witten and Klebanov-Tseytlin backgrounds, both constructed over the singular conifold; and we also study the Klebanov- Strassler solution,

Daniel Arean Fraga

265

Type-IIB Killing spinors and calibrations  

Microsoft Academic Search

In this paper we derive the full set of differential equations and some algebraic relations for p-forms constructed from type IIB Killing spinors. These equations are valid for the most general type IIB supersymmetric backgrounds which have a non-zero NS-NS 3-form field strength, H, and non-zero R-R field strengths, G(1), G(3) and G(5). Our motivation is to use these equations

Emily J. Hackett-Jones; Douglas J. Smith

2004-01-01

266

Killing spinors of some supergravity solutions  

Microsoft Academic Search

We compute explicitly the Killing spinors of some ten dimensional supergravity solutions. We begin with a 10d metric of the form $\\\\RR^{1,3}\\\\times{\\\\cal Y}_6$, where ${\\\\cal Y}_6$ is either the singular conifold or any of its resolutions. Then, we move on to the Klebanov-Witten and Klebanov-Tseytlin backgrounds, both constructed over the singular conifold; and we also study the Klebanov-Strassler solution, built

Daniel Arean

2006-01-01

267

Killed Vaccines: Cholera, Typhoid, and Plague  

Microsoft Academic Search

\\u000a As reviewed in previous chapters of this work, the earliest vaccines were of the live variety, either based on a naturally\\u000a occurring weaker version of pathogen, as with Jenner’s use of cowpox, or the laboratory-manipulated, attenuated forms of anthrax\\u000a and rabies employed by his vaccine heir, Pasteur. The next important concept in vaccine science, killed vaccines, was introduced\\u000a in animals

Charles C. J. Carpenter; Richard B. Hornick

268

Monoclonal antibody targets, kills leukemia cells  

Cancer.gov

Researchers at the University of California, San Diego Moores Cancer Center have identified a humanized monoclonal antibody that targets and directly kills chronic lymphocytic leukemia (CLL) cells. The findings, published in the online Early Edition of the Proceedings of the National Academy of Sciences on March 25, 2013 represent a potential new therapy for treating at least some patients with CLL, the most common type of blood cancer in the United States.

269

Probiotics to Target the Intestinal and Vaginal Microbiota in HIV.  

E-print Network

??The human immunodeficiency virus (HIV) preferentially targets, infects and kills CD4+ lymphocytes, which are essential for initiating an immune response against invading micro-organisms. Ultimately the… (more)

Hummelen, R.B.S.

2011-01-01

270

Genome Sequence of Paenibacillus alvei DSM 29, a Secondary Invader during European Foulbrood Outbreaks  

PubMed Central

Paenibacillus alvei is known as a secondary invader during European foulbrood of honeybees. Here, we announce the 6.83-Mb draft genome sequence of P. alvei type strain DSM 29. Putative genes encoding an antimicrobial peptide, a binary toxin, a mosquitocidal toxin, alveolysin, and different polyketides and nonribosomal peptides were identified. PMID:23105091

Djukic, Marvin; Becker, Dominik; Poehlein, Anja; Voget, Sonja

2012-01-01

271

Optimal Public Control of Exotic Species: Preventing the Brown Tree Snake from Invading Hawai'i  

Microsoft Academic Search

This paper develops a theoretical model for the efficient establishment of economic policy pertaining to invasive species, integrating prevention and control of invasive species into a single model of optimal control policy, and applies this model to the case of the Brown tree snake as a potential invader of Hawaii. The arrival of a new species to an existing ecosystem

Brooks Kaiser; James Roumasset

272

Impact: Toward a Framework for Understanding the Ecological Effects of Invaders  

Microsoft Academic Search

Although ecologists commonly talk about the impacts of nonindigenous species, little formal attention has been given to defining what we mean by impact, or connecting ecological theory with particular measures of impact. The resulting lack of generalizations regarding invasion impacts is more than an academic problem; we need to be able to distinguish invaders with minor effects from those with

I. M. Parker; D. Simberloff; W. M. Lonsdale; K. Goodell; M. Wonham; P. M. Kareiva; M. H. Williamson; B. Von Holle; P. B. Moyle; J. E. Byers; L. Goldwasser

1999-01-01

273

Impact of Alien Plant Invaders on Pollination Networks in Two Archipelagos  

PubMed Central

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

Padron, Benigno; Traveset, Anna; Biedenweg, Tine; Diaz, Diana; Nogales, Manuel; Olesen, Jens M.

2009-01-01

274

Genetic cryptic species as biological invaders: the case of a Lessepsian fish migrant,  

E-print Network

that are invading the Mediterranean from the Red Sea via the Suez Canal. We PCR amplified and sequenced. The opening of the Suez Canal in 1869, connecting the tropical Red Sea to the subtropical waters the opening of the Suez Canal (Tillier, 1902). It is a small inshore pelagic species, with a very wide

Bernardi, Giacomo

275

Invading populations of an ornamental shrub show rapid life history evolution despite genetic  

E-print Network

highlight the potential for even genetically depauperate founding populations to adapt and evolve invasiveLETTER Invading populations of an ornamental shrub show rapid life history evolution despite genetic bottlenecks Katrina M. Dlugosch* and Ingrid M. Parker Ecology and Evolutionary Biology, University

Linder, Tamás

276

Predicting Incursion of Plant Invaders into Kruger National Park, South Africa: The Interplay of General  

E-print Network

Predicting Incursion of Plant Invaders into Kruger National Park, South Africa: The Interplay, South African National Parks, Skukuza, South Africa, 4 Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa, 5 Department of Plant Science, University

Kratochvíl, Lukas

277

Fire and grazing in a shrub-invaded arid grassland community: independent or interactive ecological effects?  

Microsoft Academic Search

This study examined the response of summer and winter annuals and perennials in a shrub-invaded arid plant community to combinations of fire and grazing by cattle to determine their effects on individual abundances, species richness and diversity. Thirteen species differed significantly in abundance across the burn treatment while nine differed significantly across the grazing treatment. Summer and winter annual plants

Thomas J. Valone; Douglas A. Kelt

1999-01-01

278

Effects of native species diversity and resource additions on invader impact.  

PubMed

Theory and empirical work have demonstrated that diverse communities can inhibit invasion. Yet, it is unclear how diversity influences invader impact, how impact varies among exotics, and what the relative importance of diversity is versus extrinsic factors that themselves can influence invasion. To address these issues, we established plant assemblages that varied in native species and functional richness and crossed this gradient in diversity with resource (water) addition. Identical assemblages were either uninvaded or invaded with one of three exotic forbs: spotted knapweed (Centaurea maculosa), dalmatian toadflax (Linaria dalmatica), or sulfur cinquefoil (Potentilla recta). To determine impacts, we measured the effects of exotics on native biomass and, for spotted knapweed, on soil moisture and nitrogen levels. Assemblages with high species richness were less invaded and less impacted than less diverse assemblages. Impact scaled with exotic biomass; spotted knapweed had the largest impact on native biomass compared with the other exotics. Although invasion depressed native biomass, the net result was to increase total community yield. Water addition increased invasibility (for knapweed only) but had no effect on invader impact. Together, these results suggest that diversity inhibits invasion and reduces impact more than resource additions facilitate invasion or impact. PMID:18554141

Maron, John L; Marler, Marilyn

2008-07-01

279

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

NASA Technical Reports Server (NTRS)

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)

1968-01-01

280

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

PubMed

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

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

2013-06-01

281

Competitive interactions between two successful molluscan invaders of freshwaters: an experimental study  

Microsoft Academic Search

The New Zealand mud snail Potamopyrgus antipodarum (Hydrobiidae) and the pulmonate Physella acuta (Physidae) have invaded freshwaters in many parts of the world and become established. They co-exist in many streams, lakes and ponds in New Zealand, often at high densities. In the present study the effects of intraspecific- and interspecific interactions between the two species on growth and reproductive

Neisha J. Cope; Michael J. Winterbourn

2004-01-01

282

For the past 26 years, robots have invaded Caltech each spring to battle for their makers'  

E-print Network

For the past 26 years, robots have invaded Caltech each spring to battle for their makers' bragging teams of undergrads competed in an "extreme recy- cling" challenge that pitted pairs of robotic vehicles against difficult terrain and other robots in an effort to collect plastic water bottles, aluminum cans

283

Hedonic Analysis of Effects of a Nonnative Invader ( Myriophyllum heterophyllum ) on New Hampshire (USA) Lakefront Properties  

Microsoft Academic Search

Introduced species are a major threat to the planet’s ecosystems and one of the major causes of species extinction. This study deals with some of the economic impacts of one of these “invaders,” variable milfoil. Variable milfoil can clog waterbodies, cause boating and swimming hazards, and crowd out native species. This study analyzed the effects of variable milfoil on shoreline

John M. Halstead; Jodi Michaud; Shanna Hallas-Burt; Julie P. Gibbs

2003-01-01

284

A complex relationship: the interaction among symbiotic microbes, invading pathogens, and their mammalian host  

Microsoft Academic Search

Symbiosis between microbes and their mammalian host is vital to maintaining homeostasis. Symbiotic microbes within the gastrointestinal tract provide an array of benefits to the host, including promotion of host immunity. A coordinated effort of the host and symbiotic microbes deters the colonization and survival of many invading pathogens. However, pathogens have devised strategies to overcome these mechanisms. Furthermore, some

M M Curtis; V Sperandio

2011-01-01

285

Temporally variable dispersal and demography can accelerate the spread of invading species  

Microsoft Academic Search

We analyze how temporal variability in local demography and dispersal combine to affect the rate of spread of an invading species. Our model combines state-structured local demography (specified by an integral or matrix projection model) with general dispersal distributions that may depend on the state of the individual or its parent, and it allows very general patterns of stationary temporal

Stephen P. Ellner; Sebastian J. Schreiber

2011-01-01

286

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

Microsoft Academic Search

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.

James A Nicholls; Pablo Fuentes-Utrilla; Alexander Hayward; George Melika; György Csóka; José-Luis Nieves-Aldrey; Juli Pujade-Villar; Majid Tavakoli; Karsten Schönrogge; Graham N Stone

2010-01-01

287

Endoscopic treatment of lung cancer invading the airway before induction chemotherapy and surgical resection  

Microsoft Academic Search

Objective: Many patients with advanced lung cancer invading the airway require only palliation; however, induction chemotherapy and surgery may sometimes be considered. Preliminary endoscopic palliation may improve quality of life and functional status, allows better evaluation of tumor extension and contributes to prevent infectious complications. We reviewed our experience with preliminary laser treatment, induction chemotherapy and surgical resection in patients

Federico Venuta; Erino A. Rendina; Tiziano De Giacomo; Edoardo Mercadante; Anna Maria Ciccone; Maria Teresa Aratari; Marco Moretti; Giorgio Furio Coloni

2001-01-01

288

Endoscopic treatment of lung cancer invading the airway before induction chemotherapy and surgical resectionq  

Microsoft Academic Search

Objective: Many patients with advanced lung cancer invading the airway require only palliation; however, induction chemotherapy and surgery may sometimes be considered. Preliminary endoscopic palliation may improve quality of life and functional status, allows better evaluation of tumor extension and contributes to prevent infectious complications. We reviewed our experience with preliminary laser treatment, induction chemotherapy and surgical resection in patients

Federico Venuta; Erino A. Rendina; Tiziano De Giacomo; Edoardo Mercadante; Anna Maria Ciccone; Maria Teresa Aratari; Marco Moretti; Giorgio Furio Coloni

2010-01-01

289

2005. The Journal of Arachnology 33:16 BEHAVIOR OF WEB-INVADING SPIDERS ARGYRODES  

E-print Network

1 2005. The Journal of Arachnology 33:1­6 BEHAVIOR OF WEB-INVADING SPIDERS ARGYRODES ARGENTATUS (THERIDIIDAE) IN ARGIOPE APPENSA (ARANEIDAE) HOST WEBS IN GUAM Alexander M. Kerr1 : Marine Laboratory, University of Guam, Mangilao GU 96923 USA ABSTRACT. Most Argyrodes live in the webs of other spiders

Kerr, Alexander M.

290

Impact of invasive plants on the species richness, diversity and composition of invaded communities  

Microsoft Academic Search

Summary 1. Much attention has been paid to negative effects of alien species on resident communities but studies that quantify community-level effects of a number of invasive plants are scarce. We address this issue by assessing the impact of 13 species invasive in the Czech Republic on a wide range of plant communities. 2. Vegetation in invaded and uninvaded plots

Martin Hejda; Petr Pyšek; Vojt?ch Jarošík

2009-01-01

291

Streptococcus pneumoniae Invades Erythrocytes and Utilizes Them to Evade Human Innate Immunity  

E-print Network

@dent.niigata-u.ac.jp Introduction Severe community-acquired pneumonia reported to be the mosStreptococcus pneumoniae Invades Erythrocytes and Utilizes Them to Evade Human Innate Immunity pneumoniae, a Gram-positive bacterium, is a major cause of invasive infection-related diseases

Nizet, Victor

292

Evaluation of sheep grazing as a tool to restore mountain pastures invaded by Euphorbia polygalifolia  

Microsoft Academic Search

SUMMARY - Two experiments were conducted to (i) study whether sheep grazing pastures infested by a spurge (Euphorbia polygalifolia) consume this invasive weed and its consequences on animal performance, and (ii) detect differences between sheep and cattle in ruminal degradation of infested pastures. In the first trial, sheep grazed fenced paddocks highly invaded by spurge at instantaneous stocking rates of

M. J. Mora; J. Busqué; G. Hervás; A. R. Mantecón; B. Fernández; P. Frutos

293

Invadable Self-Assembly: Combining Robustness with Efficiency Ho-Lin Chen  

E-print Network

Invadable Self-Assembly: Combining Robustness with Efficiency Ho-Lin Chen Stanford University Qi- inary study of algorithms for DNA self-assembly that are both robust and efficient. The Tile Assembly California Pablo Moisset de Espan´es ¶ University of Southern California Abstract DNA self

Goel, Ashish

294

Can HIV invade a population which is already sick? Rinaldo B. Schinazi  

E-print Network

Can HIV invade a population which is already sick? Rinaldo B. Schinazi University of Colorado and Universit´e de Provence email: schinazi@math.uccs.edu Abstract. It is known that an HIV infection when concomitant with another disease such as tuberculosis or pneumonia is a lot more lethal than HIV alone. We

Schinazi, Rinaldo

295

Managing beyond the invader: manipulating disturbance of natives simplifies control efforts  

Microsoft Academic Search

Summary 1. Invasive plants have negative impacts on ecosystems worldwide. Several ecological studies have identified disturbance as a causative mechanism of plant invasions. Changes to natural disturbances and\\/or newly imposed disturbances can favour an invader over native species especially those that are better adapted to prior conditions. 2. To link the disturbance ecology of invasives to their management, we investigated

Jennifer Firn; Tracy Rout; Hugh Possingham; Yvonne M. Buckley

2008-01-01

296

The form of Killing vectors in expanding HH spaces  

Microsoft Academic Search

The Killing vector structure of those spaces of complexified general relativity known as expanding hyperheavens is investigated using the methods of spinor calculus. The Killing equations for all left-algebraically degenerate Einstein vacuum spaces are completely integrated. Using the available gauge freedom, the resulting homothetic and isometric Killing vectors are classified in an invariant way according to Petrov–Penrose type. A total

Stephanie A. Sonnleitner; J. D. Finley

1982-01-01

297

Killing Spinors and Superparticles in Anti-de Sitter Space  

NASA Astrophysics Data System (ADS)

The structure of Killing spinors in AdS2 space is examined in detail and the supersymmetry algebra of this space in spinors and Killing vectors is constructed. The supersymmetric mechanics corresponding to this superalgebra is constructed, and the similarity of Killing spinors and supercharges is revealed.

Orekhov, K. A.

2014-07-01

298

7Dimensional compact Riemannian manifolds with Killing spinors  

Microsoft Academic Search

Using a link between Einstein-Sasakian structures and Killing spinors we prove a general construction principle of odd-dimensional Riemannian manifolds with real Killing spinors. In dimensionn=7 we classify all compact Riemannian manifolds with two or three Killing spinors. Finally we classify nonflat 7-dimensional Riemannian manifolds with parallel spinor fields.

Thomas Friedrich; Ines Kath

1990-01-01

299

Geometric aspects of transversal Killing spinors on Riemannian flows  

E-print Network

Geometric aspects of transversal Killing spinors on Riemannian flows Nicolas Ginoux #3; , Georges Habib y Abstract. We study a Killing spinor type equation on spin Riemannian flows. We prove Classification: 53C12, 53C27 Key words: Foliations, Spin Geometry 1 Introduction Killing spinors on Riemannian

Recanati, Catherine

300

Geometric aspects of transversal Killing spinors on Riemannian flows  

E-print Network

Geometric aspects of transversal Killing spinors on Riemannian flows Nicolas Ginoux , Georges Habib Abstract. We study a Killing spinor type equation on spin Riemannian flows. We prove integrability Classification: 53C12, 53C27 Key words: Foliations, Spin Geometry 1 Introduction Killing spinors on Riemannian

Paris-Sud XI, Université de

301

A note on real Killing spinors in Weyl geometry  

Microsoft Academic Search

This note is dedicated to the real Killing equation on three-dimensional Weyl manifolds. Any manifold admitting a real Killing spinor of weight 0 satisfies the conditions of a Gauduchon–Tod geometry. Conversely, any simply connected Gauduchon–Tod geometry has a two-dimensional space of solutions of the real Killing equation on the spinor bundle of weight 0.

Volker Buchholz

2000-01-01

302

Road-Killed Animals as Resources for Ecological Studies.  

ERIC Educational Resources Information Center

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…

Adams, Clark E.

1983-01-01

303

Killing Vector Fields of Standard Static Space-times  

Microsoft Academic Search

We consider Killing vector fields on standard static space-times and obtain equations for a vector field on a standard static space-time to be Killing. We also provide a characterization of Killing vector fields on standard static space-times with compact Riemannian parts.

Fernando Dobarro; Bulent Unal

2008-01-01

304

7 CFR 29.1018 - Fire-killed.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Fire-killed. 29.1018 Section...Foreign Type 92) § 29.1018 Fire-killed. Any leaf of which...its surface has a set green color caused by excessive heat in...tobacco may be described as fire-killed. (See Rule...

2012-01-01

305

7 CFR 29.1018 - Fire-killed.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Fire-killed. 29.1018 Section...Foreign Type 92) § 29.1018 Fire-killed. Any leaf of which...its surface has a set green color caused by excessive heat in...tobacco may be described as fire-killed. (See Rule...

2011-01-01

306

7 CFR 29.1018 - Fire-killed.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Fire-killed. 29.1018 Section...Foreign Type 92) § 29.1018 Fire-killed. Any leaf of which...its surface has a set green color caused by excessive heat in...tobacco may be described as fire-killed. (See Rule...

2013-01-01

307

It's Not Just Conflict That Motivates Killing of Orangutans  

PubMed Central

We investigated why orangutans are being killed in Kalimantan, Indonesia, and the role of conflict in these killings. Based on an analysis of interview data from over 5,000 respondents in over 450 villages, we also assessed the socio-ecological factors associated with conflict and non-conflict killings. Most respondents never kill orangutans. Those who reported having personally killed an orangutan primarily did so for non-conflict reasons; for example, 56% of these respondents said that the reason they had killed an orangutan was to eat it. Of the conflict-related reasons for killing, the most common reasons orangutans were killed was fear of orangutans or in self-defence. A similar pattern was evident among reports of orangutan killing by other people in the villages. Regression analyses indicated that religion and the percentage of intact forest around villages were the strongest socio-ecological predictors of whether orangutans were killed for conflict or non-conflict related reasons. Our data indicate that between 44,170 and 66,570 orangutans were killed in Kalimantan within the respondents’ active hunting lifetimes: between 12,690 and 29,024 for conflict reasons (95%CI) and between 26,361 and 41,688 for non-conflict reasons (95% CI). These findings confirm that habitat protection alone will not ensure the survival of orangutans in Indonesian Borneo, and that effective reduction of orangutan killings is urgently needed. PMID:24130707

Davis, Jacqueline T.; Mengersen, Kerrie; Abram, Nicola K.; Ancrenaz, Marc; Wells, Jessie A.; Meijaard, Erik

2013-01-01

308

9 CFR 113.207 - Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus.  

Code of Federal Regulations, 2013 CFR

...Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus...Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus. Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed...

2013-01-01

309

9 CFR 113.207 - Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus.  

...Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus...Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus. Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed...

2014-01-01

310

9 CFR 113.207 - Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus.  

Code of Federal Regulations, 2011 CFR

...Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus...Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus. Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed...

2011-01-01

311

9 CFR 113.207 - Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus.  

Code of Federal Regulations, 2012 CFR

...Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus...Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed Virus. Encephalomyelitis Vaccine, Eastern, Western, and Venezuelan, Killed...

2012-01-01

312

Natural products containing 'decalin' motif in microorganisms.  

PubMed

Microorganisms are well-known producers of a wide variety of bioactive compounds that are utilized not only for their primary metabolism but also for other purposes such as defense, detoxification, or communication with other micro- and macro-organisms. Natural products containing a 'decalin ring' occur often in microorganisms. They exhibit diverse and remarkable biological activities, including antifungal, antibacterial, anticancer and immunosuppressive activities, to name a few. This review surveys the natural decalin-type compounds that have been isolated from microorganisms, with emphasis on both chemical and biological implications. Total syntheses of some important decalin moiety-containing natural products are also highlighted. PMID:24984916

Li, Gang; Kusari, Souvik; Spiteller, Michael

2014-09-01

313

Antimicrobial Photodynamic Therapy to Kill Gram-negative Bacteria  

PubMed Central

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

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

2013-01-01

314

Detection and differentiation of wild-type and vaccine mutant varicella-zoster viruses using an Invader Plus ® method  

Microsoft Academic Search

We report the use of a prototype Invader Plus® method (Third Wave Technologies, Inc., Madison, WI) for the qualitative detection of varicella-zoster virus (VZV) and differentiation of wild-type and Oka vaccine VZV. The analytical sensitivity of the VZV Invader Plus reagents is at 10 copies per reaction. A total of 174 skin and mucous swab specimens were used to validate

Yi-Wei Tang; Hatim T. Allawi; Marlene DeLeon-Carnes; Haijing Li; Stephen P. Day; D. Scott Schmid

2007-01-01

315

40 CFR 725.88 - Uses of a microorganism.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Uses of a microorganism. 725.88 Section 725...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public...Information § 725.88 Uses of a microorganism. (a) Assertion of...

2010-07-01

316

40 CFR 725.88 - Uses of a microorganism.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Uses of a microorganism. 725.88 Section 725...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public...Information § 725.88 Uses of a microorganism. (a) Assertion of...

2013-07-01

317

40 CFR 725.88 - Uses of a microorganism.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Uses of a microorganism. 725.88 Section 725...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public...Information § 725.88 Uses of a microorganism. (a) Assertion of...

2011-07-01

318

40 CFR 725.88 - Uses of a microorganism.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Uses of a microorganism. 725.88 Section 725...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Confidentiality and Public...Information § 725.88 Uses of a microorganism. (a) Assertion of...

2012-07-01

319

The form of Killing vectors in expanding scriptscript spaces  

NASA Astrophysics Data System (ADS)

The Killing vector structure of those spaces of complexified general relativity known as expanding hyperheavens is investigated using the methods of spinor calculus. The Killing equations for all left-algebraically degenerate Einstein vacuum spaces are completely integrated. Using the available gauge freedom, the resulting homothetic and isometric Killing vectors are classified in an invariant way according to Petrov-Penrose type. A total of four distinct kinds of isometric Killing vectors and three distinct kinds of homothetic Killing vectors are found. A master Killing vector equation is found which gives the form that the Lie derivative of the metric potential function W must take in order that it admit a given Killing vector.

Sonnleitner, Stephanie A.; Finley, J. D., III

1982-01-01

320

Study of Soil Microorganisms - Inuvik, Northwest Territories.  

National Technical Information Service (NTIS)

A study of soil microorganisms of the Inuvik area was carried out during the summer of 1964. In almost all samples taken, psychrophilic, mesophilic, and especially thermophilic bacteria were found in greater numbers than in samples obtained from northern ...

W. L. Boyd, J. W. Boyd

1971-01-01

321

Atmospheric Benzene Depletion by Soil Microorganisms.  

National Technical Information Service (NTIS)

Gaseous benzene was rapidly depleted in exposure chambers containing viable soils and plants. When separate components of the system were analyzed, no benzene was detected in soils, plants, or water. Soil microorganisms were shown to be responsible for me...

J. C. McFarlane, A. Cross, C. Frank, R. D. Rogers

1981-01-01

322

Studies of Soil Microorganisms of North Norway.  

National Technical Information Service (NTIS)

Soils of northern Norway have fewer microorganisms than are found in temperate regions. Thermophilic bacteria are present rarely except where cultivation has taken place or where possible pollution or disturbance has occurred. Mesophilic and psychrophilic...

W. L. Boyd, J. W. Boyd

1971-01-01

323

Ecology of Soil Microorganisms of Antarctica.  

National Technical Information Service (NTIS)

Continental Antarctica possesses a characteristic flora and fauna, which varies both qualitatively and quantitatively among the different habitats. Bacteria and other microorganisms are usually present in numbers far lower than those encountered in temper...

W. L. Boyd, J. T. Staley, J. W. Boyd

1966-01-01

324

Detection of microorganisms using terahertz metamaterials  

PubMed Central

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

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

325

A microfabricated dielectrophoretic micro-organism concentrator  

E-print Network

This project focuses on the development of a micro-organism concentrator. Pathogen detection, particularly MEMS based detection, is often limited by sample concentration. The proposed concentrator will interface with a ...

Muller, Rikky, 1980-

2004-01-01

326

Effects of forest fertilization on soil microorganisms.  

National Technical Information Service (NTIS)

The effects of forest fertilization on soil microorganisms were examined using different methods. Clear effects were found. The microbial biomass, estimated using the substrate induced respiration rate (SIR) technique, or as ATP content was found to be re...

K. Arnebrandt

1991-01-01

327

Detection of microorganisms using terahertz metamaterials.  

PubMed

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

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

328

Myeloperoxidase Selectively Binds and Selectively Kills Microbes ? †  

PubMed Central

Myeloperoxidase (MPO) is reported to selectively bind to bacteria. The present study provides direct evidence of MPO binding selectivity and tests the relationship of selective binding to selective killing. The microbicidal effectiveness of H2O2 and of OCl? was compared to that of MPO plus H2O2. Synergistic microbicidal action was investigated by combining Streptococcus sanguinis, a H2O2-producing microbe showing low MPO binding, with high-MPO-binding Escherichia coli, Staphylococcus aureus, or Pseudomonas aeruginosa without exogenous H2O2, with and without MPO, and with and without erythrocytes (red blood cells [RBCs]). Selectivity of MPO microbicidal action was conventionally measured as the MPO MIC and minimal bactericidal concentration (MBC) for 82 bacteria including E. coli, P. aeruginosa, S. aureus, Enterococcus faecalis, Streptococcus pyogenes, Streptococcus agalactiae, and viridans streptococci. Both H2O2 and OCl? destroyed RBCs at submicrobicidal concentrations. Nanomolar concentrations of MPO increased H2O2 microbicidal action 1,000-fold. Streptococci plus MPO produced potent synergistic microbicidal action against all microbes tested, and RBCs caused only a small decrease in potency without erythrocyte damage. MPO directly killed H2O2-producing S. pyogenes but was ineffective against non-H2O2-producing E. faecalis. The MPO MICs and MBCs for E. coli, P. aeruginosa, and S. aureus were significantly lower than those for E. faecalis. The streptococcal studies showed much higher MIC/MBC results, but such testing required lysed horse blood-supplemented medium, thus preventing valid comparison of these results to those for the other microbes. E. faecalis MPO binding is reportedly weak compared to binding of E. coli, P. aeruginosa, and S. aureus but strong compared to binding of streptococci. Selective MPO binding results in selective killing. PMID:20974824

Allen, Robert C.; Stephens, Jackson T.

2011-01-01

329

Automated systems for identification of microorganisms.  

PubMed Central

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

Stager, C E; Davis, J R

1992-01-01

330

What Killed The Dinosaurs?: The Great Mystery  

NSDL National Science Digital Library

This site presents theories about why the dinosaurs became extinct. The first page provides background information covering not only the "great dying" at the K-T boundary but also the mass extinction at the end of the Paleozoic Era. The author covers six factors that complicate the study of mass extinction including time resolution, the Signor-Lipps Effect, and falsifiability. A link then takes the reader to a second page where invalid extinction hypotheses are explained. These range from "hay fever killed the dinosaurs" to "the dinosaurs just faded away," (no causation implied). The final link leads us to current thinking about extinction including volcanism, plate tectonics, and the Alvarez Hypothesis.

Hutchinson, John

331

The killing efficiency of soft iron shot  

USGS Publications Warehouse

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.

Andrews, R.; Longcore, J.R.

1969-01-01

332

Anti-biofilm activity of silver nanoparticles against different microorganisms.  

PubMed

Biofilms confer protection from adverse environmental conditions and can be reservoirs for pathogenic organisms and sources of disease outbreaks, especially in medical devices. The goal of this research was to evaluate the anti-biofilm activities of silver nanoparticles (AgNPs) against several microorganisms of clinical interest. The antimicrobial activity of AgNPs was tested within biofilms generated under static conditions and also under high fluid shears conditions using a bioreactor. A 4-log reduction in the number of colony-forming units of Pseudomonas aeruginosa was recorded under turbulent fluid conditions in the CDC reactor on exposure to 100?mg?ml(-1) of AgNPs. The antibacterial activity of AgNPs on various microbial strains grown on polycarbonate membranes is reported. In conclusion, AgNPs effectively prevent the formation of biofilms and kill bacteria in established biofilms, which suggests that AgNPs could be used for prevention and treatment of biofilm-related infections. Further research and development are necessary to translate this technology into therapeutic and preventive strategies. PMID:23731460

Martinez-Gutierrez, Fidel; Boegli, Laura; Agostinho, Alessandra; Sánchez, Elpidio Morales; Bach, Horacio; Ruiz, Facundo; James, Garth

2013-01-01

333

New Brane Solutions from Killing Spinor Equations  

E-print Network

In a recent paper, we have pointed out a relation between the Killing spinor and Einstein equations. Using this relation, new brane solutions of D=11 and D=10 type IIB supergravity theories are constructed. It is shown that in a brane solution, the flat world-volume directions, the smeared transverse directions and the sphere located at a fixed radial distance can be replaced with any Lorentzian Ricci flat, Euclidean Ricci flat and Einstein manifolds, respectively. The solution obtained in this fashion is supersymmetric when the Ricci flat and Einstein manifolds have Killing spinors. We generalize intersecting brane solutions, in which M5, M2 and D3-branes also wrap over the cycles determined by the K\\"{a}hler forms of Ricci flat K\\"{a}hler manifolds. New, singular, Ricci flat manifolds as (generalized) cones over the U(1) bundles over Ricci flat K\\"{a}hler spaces are constructed. These manifolds have covariantly constant spinors and give rise to new, supersymmetric, Ricci flat compactifications of non-gauged supergravity theories. We find M2 and D3-brane solutions, which asymptotically approach these singular vacua.

Ali Kaya

2000-04-27

334

Aquatic Invaders  

NSDL National Science Digital Library

In this lesson plan students will explore the ways that native species interact in a healthy Chesapeake Bay. They will then learn about some of the ways that exotic or invasive species can threaten the balance of the ecosystem. Students will discover how the various elements of the Bay ecosystem are interconnected and investigate some of the issues associated with invasive species.

335

Transmanubrial osteomuscular sparing approach for lung cancer invading the anterior part of the thoracic inlet.  

PubMed

Standard treatment for lung cancer presenting as a superior sulcus tumor is induction chemoradiotherapy followed by surgery, which yields rates of about 70% complete resection and 50% 5-year survival rate. However, the surgical technique to achieve complete resection for superior sulcus tumor invading major anatomical sites including the subclavian artery is challenging. The anterior transcervical thoracic approach applied by Dartevelle and colleagues provides excellent exposure of the subclavian vessels. Grunenwald and associates have improved on this approach to preserve the clavicle and sternoclavicular joint. We applied the transmanubrial osteomuscular-sparing approach in two patients. In both cases, exposure of the subclavian vessels was excellent. In one case, the subclavian artery was resected and reconstructed with a polytetrafl uoroethylene graft. This patient has continued to show recurrence-free survival for more than 5 years. We outline our experience and review the literature on the surgical approach for superior sulcus tumor invading the anterior part of the thoracic inlet. PMID:20349307

Matsuguma, Haruhisa; Nakahara, Rie; Ishikawa, Yoshinori; Suzuki, Haruko; Ui, Akiko; Yokoi, Kohei

2010-03-01

336

Extended resection of lung cancer invading the left subclavian artery by using cardiopulmonary bypass.  

PubMed

We treated a 54-year-old man with large cell carcinoma of the left upper lobe invading the esophagus and the left subclavian artery (SCA) from its origin. The tumor was completely resected by lobectomy under cardiopulmonary bypass. The left SCA was dissected at the aortic arch and reconstructed with a graft. The muscle layer of the esophagus was resected, followed by patching with an intercostal muscle flap. The pathological tumor stage was T4N0M0. The tumor recurred at two months after surgery in the neck lymph nodes and brain. Both sites were treated with radiation therapy and the patient is now alive without recurrence at 26 months after surgery. Lung cancer invading the great vessels and other mediastinal structures can be cured or long survival can be obtained by extended resection and postoperative adjuvant therapy. PMID:16030485

Nomori, Hiroaki; Hirotani, Takashi; Watanabe, Kenichi; Ohtsuka, Takashi; Naruke, Tsuguo; Suemasu, Keiichi

2005-06-01

337

Chronic kidney disease is associated with incident cognitive impairment in the elderly: the INVADE study  

Microsoft Academic Search

Background. Limited data exist regarding the relation- ship between decreased renal function and cognitive impairment. Methods. A total of 3679 participants of the Interven- tion Project on Cerebrovascular Diseases and Dementia in the Community of Ebersberg (INVADE) composed the community-based cohort study. Measures of renal func- tion were estimated using the Cockcroft-Gault equation and divided into normal, mild and moderate-to-severe

Thorleif Etgen; Dirk Sander; Michel Chonchol; Holger Poppert; Hans F; Horst Bickel

2009-01-01

338

Competitive interactions between co-occurring invaders: identifying asymmetries between two invasive crayfish species  

Microsoft Academic Search

Ecosystems today increasingly suffer invasions by multiple invasive species. Complex interactions between invasive species\\u000a can have different fitness implications for each invader, which can in turn determine the future progression of their invasions\\u000a and result in differential impacts on native species and ecosystems. To this end, through pair-wise and group scale experiments,\\u000a we examined possible interaction outcomes, competition effects and

Sandra Hudina; Nika Gali?; Ivo Roessink; Karlo Hock

2011-01-01

339

Chinese mitten crab Eriocheir sinensis in the Baltic Sea—a supply-side invader?  

Microsoft Academic Search

Although the Chinese mitten crab Eriocheir sinensis (H. Milne-Edwards, 1853) (Crustacea, Decapoda, Varunidae) invaded the Baltic Sea about 80 years ago, published information\\u000a on its present distribution and abundance in this region is lacking. We provide here information on its Baltic-wide distribution\\u000a and long-term population dynamics. The species has been found all over the coastal Baltic Sea and also in some

Henn Ojaveer; Stephan Gollasch; Andres Jaanus; Jonne Kotta; Ari O. Laine; Atis Minde; Monika Normant; Vadim E. Panov

2007-01-01

340

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

PubMed Central

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

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

2014-01-01

341

Naturally Processed Dermcidin-Derived Peptides Do Not Permeabilize Bacterial Membranes and Kill Microorganisms Irrespective of Their Charge  

Microsoft Academic Search

Dermcidin (DCD) is a recently described antimicrobial peptide, which is constitutively expressed in eccrine sweat glands and transported via sweat to the epidermal surface. By postsecretory proteolytic processing in sweat the dermcidin protein gives rise to several truncated DCD peptides which differ in length and net charge. In order to understand the mechanism of antimicrobial activity, we analyzed the spectrum

H. Steffen; S. Rieg; I. Wiedemann; H. Kalbacher; M. Deeg; H.-G. Sahl; A. Peschel; F. Gotz; C. Garbe; B. Schittek

2006-01-01

342

Functional microorganisms for functional food quality.  

PubMed

Functional microorganisms and health benefits represent a binomial with great potential for fermented functional foods. The health benefits of fermented functional foods are expressed either directly through the interactions of ingested live microorganisms with the host (probiotic effect) or indirectly as the result of the ingestion of microbial metabolites synthesized during fermentation (biogenic effect). Since the importance of high viability for probiotic effect, two major options are currently pursued for improving it--to enhance bacterial stress response and to use alternative products for incorporating probiotics (e.g., ice cream, cheeses, cereals, fruit juices, vegetables, and soy beans). Further, it seems that quorum sensing signal molecules released by probiotics may interact with human epithelial cells from intestine thus modulating several physiological functions. Under optimal processing conditions, functional microorganisms contribute to food functionality through their enzyme portfolio and the release of metabolites. Overproduction of free amino acids and vitamins are two classical examples. Besides, bioactive compounds (e.g., peptides, ?-amino butyric acid, and conjugated linoleic acid) may be released during food processing above the physiological threshold and they may exert various in vivo health benefits. Functional microorganisms are even more used in novel strategies for decreasing phenomenon of food intolerance (e.g., gluten intolerance) and allergy. By a critical approach, this review will aim at showing the potential of functional microorganisms for the quality of functional foods. PMID:20830633

Gobbetti, M; Cagno, R Di; De Angelis, M

2010-09-01

343

"Brain Invaders": a prototype of an open-source P300-based video game working with the OpenViBE platform.  

E-print Network

1 "Brain Invaders": a prototype of an open-source P300- based video game working with the Open. FRANCE Marco.Congedo@gmail.com We have developed the prototype of a pure-BCI video game based on the well known vintage video game "Space Invaders". In our "Brain Invaders" a number of aliens are displayed

Paris-Sud XI, Université de

344

Facilitation of Native Stream Fauna by an Invading Species? Experimental Investigations of the Interaction of the Snail, Potamopyrgus antipodarum (Hydrobiidae) with Native Benthic Fauna  

Microsoft Academic Search

Biological invasions are regarded as a major threat to native ecosystems, yet studies investigating the interactions of invaders with native biota under field conditions are rare. Whilst many invaders are present only in low densities, it is often the effects of high densities that are of particular concern. We manipulated densities of the invading New Zealand aquatic snail Potamopyrgus antipodarum

E. S. G. Schreiber; P. S. Lake; G. P. Quinn

2002-01-01

345

The geometry of D = 11 null Killing spinors  

Microsoft Academic Search

We determine the necessary and sufficient conditions on the metric and the four-form for the most general bosonic supersymmetric configurations of D=11 supergravity which admit a null Killing spinor i.e. a Killing spinor which can be used to construct a null Killing vector. This class covers all supersymmetric time-dependent configurations and completes the classification of the most general supersymmetric configurations

Jerome P. Gauntlett; Jan B. Gutowski; Stathis Pakis

2003-01-01

346

The geometry of D = 11 null Killing spinors  

NASA Astrophysics Data System (ADS)

We determine the necessary and sufficient conditions on the metric and the four-form for the most general bosonic supersymmetric configurations of D=11 supergravity which admit a null Killing spinor i.e. a Killing spinor which can be used to construct a null Killing vector. This class covers all supersymmetric time-dependent configurations and completes the classification of the most general supersymmetric configurations initiated in hep-th/0212008.

Gauntlett, Jerome P.; Gutowski, Jan B.; Pakis, Stathis

2003-12-01

347

The Geometry of D=11 Null Killing Spinors  

E-print Network

We determine the necessary and sufficient conditions on the metric and the four-form for the most general bosonic supersymmetric configurations of D=11 supergravity which admit a null Killing spinor i.e. a Killing spinor which can be used to construct a null Killing vector. This class covers all supersymmetric time-dependent configurations and completes the classification of the most general supersymmetric configurations initiated in hep-th/0212008.

Jerome P. Gauntlett; Jan B. Gutowski; Stathis Pakis

2003-11-13

348

The geometry of D = 11 null Killing spinors  

Microsoft Academic Search

We determine the necessary and sufficient conditions on the metric and the four-form for the most general bosonic supersymmetric configurations of D = 11 supergravity which admit a null Killing spinor i.e. a Killing spinor which can be used to construct a null Killing vector. This class covers all supersymmetric time-dependent configurations and completes the classification of the most general

Jerome P. Gauntlett; Jan B. Gutowski; Stathis Pakis

2003-01-01

349

The holonomy of the supercovariant connection and Killing spinors  

Microsoft Academic Search

We show that the holonomy of the supercovariant connection for M-theory backgrounds with N Killing spinors reduces to a subgroup of SL(32-N,Bbb R)ltimes(oplusNBbb R32-N). We use this to give the necessary and sufficient conditions for a background to admit N Killing spinors. We show that there is no topological obstruction for the existence of up to 22 Killing spinors in

George Papadopoulos; Dimitrios Tsimpis

2003-01-01

350

Killing spinors and supersymmetry on AdS  

Microsoft Academic Search

In this paper we construct several supersymmetric theories on AdS5 background. We discuss the proper definition of the Killing equation for the symplectic Majorana spinors required in AdS5 supersymmetric theories. We find that the symplectic Killing spinor equation involves a matrix M in the USp(2N) indices whose role was not recognized previously. Using the correct Killing spinors we explicitly confirm

Eugene Shuster

1999-01-01

351

Antimicrobial Peptide Killing of African Trypanosomes  

PubMed Central

Summary The diseases caused by trypanosomes are medically and economically devastating to the population of sub-Saharan Africa. Parasites of the genus Trypanosoma, infect both humans, causing African sleeping sickness, and livestock, causing Nagana. The development of effective treatment strategies has suffered from the severe side effects of approved drugs, resistance and major difficulties in delivering drugs. Antimicrobial peptides are ubiquitous components of immune defense and are being rigorously pursued as novel sources of new therapeutics for a variety of pathogens. Here we review the role of antimicrobial peptides in the innate immune response of the tsetse fly to African trypanosomes, catalogue trypanocidal antimicrobial peptides from diverse organisms and highlight the susceptibility of bloodstream form African trypanosomes to killing by unconventional toxic peptides. PMID:21517904

Harrington, John M.

2011-01-01

352

Cell death in planktonic, photosynthetic microorganisms  

Microsoft Academic Search

Phytoplankton evolved in the Archaean oceans more than 2.8 billion years ago and are of crucial importance in regulating aquatic food webs, biogeochemical cycles and the Earth's climate. Until recently, phytoplankton were considered immortal unless killed or eaten by predators. However, over the past decade, it has become clear that these organisms can either be infected by viruses or undergo

Kay D. Bidle; Paul G. Falkowski

2004-01-01

353

Hydrodynamic phase-locking of swimming microorganisms  

E-print Network

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 co-swimming cells depends only on the nature of this geometrical asymmetry, and microorganisms can phase-lock into conformations which minimize or maximize energy dissipation.

Elfring, Gwynn J

2009-01-01

354

Metabolic activity of microorganisms in evaporites  

NASA Technical Reports Server (NTRS)

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.

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

1994-01-01

355

Hydrodynamic phase-locking of swimming microorganisms  

E-print Network

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 co-swimming cells depends only on the nature of this geometrical asymmetry, and microorganisms can phase-lock into conformations which minimize or maximize energy dissipation.

Gwynn J. Elfring; Eric Lauga

2009-07-06

356

Acroptilon repens , an Asian invader, has stronger competitive effects on species from America than species from its native range  

Microsoft Academic Search

The ability to competitively suppress native species is key to successful invasion. Since invasions involve an increase in\\u000a abundance or dominance of a species in its non-native range, competitive effects might be expected to be stronger in the non-native\\u000a range of an invader; however, there have been few comparisons of the competitive effects of invasive plants on species from\\u000a invaded

Guang-Yan NiUrs; Urs Schaffner; Shao-Lin Peng; Ragan M. Callaway

2010-01-01

357

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

PubMed

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

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

2010-02-01

358

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

PubMed

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

Tamura, Mioko; Tharayil, Nishanth

2014-07-01

359

Measurement of gas production of microorganisms  

Microsoft Academic Search

A simple apparatus and method is disclosed for measuring gas production by microorganisms using a pressure transducer to sense pressure buildup by members of the Enterobacteriaceae group of bacteria. The test system consists of a 5.0 psid pressure transducer and a pressure equalizer valve attached to the metal cap of a 20 x 150 mm test tube. Gas pressure is

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

1975-01-01

360

Guide to Identification of Fresh Water Microorganisms  

NSDL National Science Digital Library

This seven-page guide can be used to identify freshwater microorganisms. Categories include microscopic autotrophic organisms (i.e. algae), heterotrophic protozoa, other freshwater plankton (Animalia, Monera, etc), and arthropods. The guide is in the form of a table, with columns for name, picture, characteristic, and taxonomy.

Nucleus, Math/science

361

ATMOSPHERIC BENZENE DEPLETION BY SOIL MICROORGANISMS  

EPA Science Inventory

Gaseous benzene was rapidly depleted in exposure chambers containing viable soils and plants. When separate components of the system were analyzed, no benzene was detected in soils, plants, or water. Soil microorganisms were shown to be responsible for metabolizing benzene, yield...

362

Removal of microorganisms by deep well injection  

Microsoft Academic Search

The removal of bacteriophages MS2 and PRD1, spores of Clostridium bifermentans (R5) and Escherichia coli (WR1) by deep well injection into a sandy aquifer, was studied at a pilot field site in the southeast of the Netherlands. Injection water was seeded with the microorganisms for 5 days. Breakthrough was monitored for 93 days at 4 monitoring wells with their screens

Jack F. Schijven; Gertjan Medema; Ad J. Vogelaar; S. Majid Hassanizadeh

2000-01-01

363

Extremophilic microorganisms as candidates for extraterrestrial life  

Microsoft Academic Search

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

Joseph Seckbach; Aharon Oren

2000-01-01

364

DNA Fragmentation in Microorganisms Assessed In Situ  

Microsoft Academic Search

Chromosomal DNA fragmentation may be a direct or indirect outcome of cell death. Unlike DNA fragmen- tation in higher eukaryotic cells, DNA fragmentation in microorganisms is rarely studied. We report an adaptation of a diffusion-based assay, developed as a kit, which allows for simple and rapid discrimination of bacteria with fragmented DNA. Intact cells were embedded in an agarose microgel

JoseLuis Fernandez; M. Cartelle; L. Muriel; R. Santiso; M. Tamayo; V. Goyanes; J. Gosalvez; G. Bou

2008-01-01

365

Genetic Manipulation of Antibiotic-Producing Microorganisms  

Microsoft Academic Search

The application of directed selection techniques and genetic engineering methods for manipulation of antibiotic-producing microorganisms is generating a new era in industrial microbiology. Modern methods, based on advances in the knowledge of the biosynthetic pathways and regulatory mechanisms involved in the induction and repression of genes involved in antibiotic synthesis, provide a means of increasing antibiotic activity. Hence, recombinant DNA

John N. Vournakis; Richard P. Elander

1983-01-01

366

Biomechanics of Aquatic Micro-Organisms  

NASA Astrophysics Data System (ADS)

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!

Pedley, T. J.

367

Radiation sensitivity of hyperthermal composting microorganisms  

Microsoft Academic Search

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

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

2010-01-01

368

Mechanisms of nickel toxicity in microorganisms  

PubMed Central

Summary Nickel has long been known to be an important human toxicant, including having the ability to form carcinomas, but until recently nickel was believed to be an issue only to microorganisms living in nickel-rich serpentine soils or areas contaminated by industrial pollution. This assumption was overturned by the discovery of a nickel defense system (RcnR/RcnA) found in microorganisms that live in a wide range of environmental niches, suggesting that nickel homeostasis is a general biological concern. To date, the mechanisms of nickel toxicity in microorganisms and higher eukaryotes are poorly understood. In this review, we summarize nickel homeostasis processes used by microorganisms and highlight in vivo and in vitro effects of exposure to elevated concentrations of nickel. On the basis of this evidence we propose four mechanisms of nickel toxicity: 1) nickel replaces the essential metal of metalloproteins, 2) nickel binds to catalytic residues of non-metalloenzymes; 3) nickel binds outside the catalytic site of an enzyme to inhibit allosterically, and 4) nickel indirectly causes oxidative stress. PMID:21799955

Macomber, Lee

2014-01-01

369

Microbial biogeography: putting microorganisms on the map  

Microsoft Academic Search

We review the biogeography of microorganisms in light of the biogeography of macroorganisms. A large body of research supports the idea that free-living microbial taxa exhibit biogeographic patterns. Current evidence confirms that, as proposed by the Baas-Becking hypothesis, 'the environment selects' and is, in part, responsible for spatial variation in microbial diversity. However, recent studies also dispute the idea that

Jennifer B. Hughes Martiny; Brendan J. M. Bohannan; James H. Brown; Robert K. Colwell; Jed A. Fuhrman; Jessica L. Green; M. Claire Horner-Devine; Matthew Kane; Jennifer Adams Krumins; Cheryl R. Kuske; Peter J. Morin; Shahid Naeem; Lise Øvreås; Anna-Louise Reysenbach; Val H. Smith; James T. Staley

2006-01-01

370

Microorganism lipid droplets and biofuel development  

PubMed Central

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

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

2013-01-01

371

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

372

Killing of bacteria during solar eclipse and its biological implications.  

PubMed

Enhanced killing of bacteria was obtained by radiation reaching the earth during total solar eclipse (February 16, 1980) than during the corresponding time of a normal day (February 26, 1980). The killing was not due to the formation of sunlight induced photoproducts of tryptophan. The damage to the bacteria exposed to sunlight could be repaired by photoreactivation. PMID:6359236

Banerjee, S K; Chatterjee, S N

1983-01-01

373

On pseudo-Riemannian manifolds with many Killing spinors  

E-print Network

]k. For k = 1 we obtain conformal Killing vector fields. Using the above correspondence, we proveOn pseudo-Riemannian manifolds with many Killing spinors D.V. Alekseevsky and V. Cort of the real spinor bundle. We prove that M is locally ho- mogeneous if it admits more than 3 4 N independent

Cortés, Vicente

374

Imaginary Killing spinors on (2, n ? 2)-manifolds  

Microsoft Academic Search

In this paper we prove that a (2, n ? 2)-manifold admitting an imaginary Killing spinor with nontrivial Dirac current, is at least locally a codimension one\\u000a warped product with a special warping function. Hence, a (2, 2)-manifold admitting such an imaginary Killing spinor is Einstein\\u000a iff it is conformally flat.

M. Shafiee; Y. Bahrampour

2009-01-01

375

On pseudo-Riemannian manifolds with many Killing spinors  

Microsoft Academic Search

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 34N independent Killing spinors with the same Killing number, unless n ? 1 (mod 4) and s ? 3 (mod 4). We also prove

D. V. Alekseevsky; V. Cortés

2009-01-01

376

Parallel and Killing Spinors on Spinc Andrei Moroianu1  

E-print Network

Parallel and Killing Spinors on Spinc Manifolds Andrei Moroianu1 Institut f¨ur reine Mathematik simply connected Spinc manifolds carrying parallel and real Killing spinors. In particular we show spinors. 1 Introduction The classification of irreducible simply connected spin manifolds with parallel

Paris-Sud XI, Université de

377

GENERALIZED KILLING SPINORS ON EINSTEIN MANIFOLDS ANDREI MOROIANU, UWE SEMMELMANN  

E-print Network

GENERALIZED KILLING SPINORS ON EINSTEIN MANIFOLDS ANDREI MOROIANU, UWE SEMMELMANN Abstract. We study generalized Killing spinors on compact Einstein manifolds with pos- itive scalar curvature. This problem is related to the existence of compact Einstein hyper- surfaces in manifolds with parallel spinors

Semmelmann, Uwe

378

Life After Fresh Kills: Moving Beyond New York City's  

E-print Network

now faces: Increasing costs: Contracts negotiated for disposal after Fresh Kills will impose significant cost increases on City taxpayers as waste disposal charges rise from the $42 per ton cost disposal plan and the impact of the Fresh Kills landfill closing. The report concludes that New York City

Columbia University

379

Pseudomonas aeruginosa PAO1 Kills Caenorhabditis elegans by Cyanide Poisoning  

PubMed Central

In this report we describe experiments to investigate a simple virulence model in which Pseudomonas aeruginosa PAO1 rapidly paralyzes and kills the nematode Caenorhabditis elegans. Our results imply that hydrogen cyanide is the sole or primary toxic factor produced by P. aeruginosa that is responsible for killing of the nematode. Four lines of evidence support this conclusion. First, a transposon insertion mutation in a gene encoding a subunit of hydrogen cyanide synthase (hcnC) eliminated nematode killing. Second, the 17 avirulent mutants examined all exhibited reduced cyanide synthesis, and the residual production levels correlated with killing efficiency. Third, exposure to exogenous cyanide alone at levels comparable to the level produced by PAO1 killed nematodes with kinetics similar to those observed with bacteria. The killing was not enhanced if hcnC mutant bacteria were present during cyanide exposure. And fourth, a nematode mutant (egl-9) resistant to P. aeruginosa was also resistant to killing by exogenous cyanide in the absence of bacteria. A model for nematode killing based on inhibition of mitochondrial cytochrome oxidase is presented. The action of cyanide helps account for the unusually broad host range of virulence of P. aeruginosa and may contribute to the pathogenesis in opportunistic human infections due to the bacterium. PMID:11591663

Gallagher, Larry A.; Manoil, Colin

2001-01-01

380

Pseudomonas aeruginosa PAO1 kills Caenorhabditis elegans by cyanide poisoning.  

PubMed

In this report we describe experiments to investigate a simple virulence model in which Pseudomonas aeruginosa PAO1 rapidly paralyzes and kills the nematode Caenorhabditis elegans. Our results imply that hydrogen cyanide is the sole or primary toxic factor produced by P. aeruginosa that is responsible for killing of the nematode. Four lines of evidence support this conclusion. First, a transposon insertion mutation in a gene encoding a subunit of hydrogen cyanide synthase (hcnC) eliminated nematode killing. Second, the 17 avirulent mutants examined all exhibited reduced cyanide synthesis, and the residual production levels correlated with killing efficiency. Third, exposure to exogenous cyanide alone at levels comparable to the level produced by PAO1 killed nematodes with kinetics similar to those observed with bacteria. The killing was not enhanced if hcnC mutant bacteria were present during cyanide exposure. And fourth, a nematode mutant (egl-9) resistant to P. aeruginosa was also resistant to killing by exogenous cyanide in the absence of bacteria. A model for nematode killing based on inhibition of mitochondrial cytochrome oxidase is presented. The action of cyanide helps account for the unusually broad host range of virulence of P. aeruginosa and may contribute to the pathogenesis in opportunistic human infections due to the bacterium. PMID:11591663

Gallagher, L A; Manoil, C

2001-11-01

381

Control of Influenza and Poliomyelitis with Killed Virus Vaccines  

ERIC Educational Resources Information Center

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)

Salk, Jonas; Salk, Darrell

1977-01-01

382

Who Killed Parliamentary Government By Dr. Gary Levy  

E-print Network

Who Killed Parliamentary Government By Dr. Gary Levy Editor, Canadian Parliamentary Review Paper and Regina University January 11, 2011 #12;Who Killed Parliamentary Government? The title despite our great debt to Professor Smith for his work on Parliament I am going to disagree somewhat

Peak, Derek

383

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

384

Microwave irradiation for rapid killing and fixing of plant tissue  

SciTech Connect

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.

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

1989-01-01

385

Baseline histopathological survey of a recently invading island population of 'killer shrimp', Dikerogammarus villosus.  

PubMed

Dikerogammarus villosus, an invasive amphipod, has recently been detected in UK freshwaters. To assess the potential for pathogen introduction with the invader, a year-long histopathology survey of the D. villosus population inhabiting the initial site of detection (Grafham Water, Cambridgeshire, UK) was conducted. Additional samples were collected from 2 other subsequently identified populations within the UK (Cardiff Bay and Norfolk Broads), and from established populations in France (River Rhine) and Poland (River Vistula). The data revealed a range of pathogens and commensals. Several pathogens occurring within continental populations were not present within the UK populations. Microsporidian parasites and a novel viral pathogen were amongst those not observed in the UK. The absence of these pathogens at UK sites may therefore impart significant survival advantages to D. villosus over native fauna, thereby increasing its success as an invader. The contrast in pathogen profile between UK and continental-invasive populations of D. villosus provides preliminary evidence for so-called 'enemy release' in UK populations of D. villosus and is suggestive of single-point introductions, rather than continual incursion events as previously observed throughout its continental invasive range. This baseline survey provides important data on the pathogen and commensal profile of a high-impact, invasive species early in its invasion history of the UK. It can be utilised to assess potential for temporal pathogen acquisition by non-native invasive aquatic species and to investigate competitive advantages placed upon this invader due to absence of important pathogens experienced within its native range. PMID:24192001

Bojko, J; Stebbing, P D; Bateman, K S; Meatyard, J E; Bacela-Spychalska, K; Dunn, A M; Stentiford, G D

2013-11-01

386

Mechanisms of Dendritic Cell Lysosomal Killing of Cryptococcus  

NASA Astrophysics Data System (ADS)

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.

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

2012-10-01

387

Optimization of weapon-target pairings based on kill probabilities.  

PubMed

In this paper, we present a novel optimization algorithm for assigning weapons to targets based on desired kill probabilities. For the given weapons, targets, and desired kill probabilities, our optimization algorithm assigns weapons to targets that satisfy the desired kill probabilities and minimize the overkill. The minimization of overkill assures that any proper subset of the weapons assigned to a target results in a kill probability that is less than the desired kill probability on such a target. Computational results for up to 120 weapons and 120 targets indicate that the performance of this algorithm yields an average improvement in quality of solutions of 26.8% over the greedy algorithms, whereas execution times remained on the order of milliseconds. PMID:24273148

Bogdanowicz, Zbigniew R; Tolano, Antony; Patel, Ketula; Coleman, Norman P

2013-12-01

388

Aphid fecundity and grassland invasion: invader life history is the key.  

PubMed

Loss or gain of pathogens can determine the trajectory of biological invasions, and invasion by novel hosts also can alter pathogen dynamics to facilitate invasion. Recent empirical and theoretical work has implicated infection by barley and cereal yellow dwarf viruses (B/CYDV), a group of generalist pathogens of the Poaceae family (grasses), as a necessary precursor to the invasion of over 9 million hectares of California's perennial grasslands by exotic annual grasses. The mechanism underlying this pathogen-mediated invasion hypothesis is elevated vector fecundity on exotic annual grasses. While empirical evidence supports this hypothesis, the links between aphid fecundity, host identity, and host resource supply have not been thoroughly assessed. We performed field and laboratory experiments to examine the fecundity and preference responses of three of the most common aphid vectors of B/CYDV, Rhopalosiphum padi (L.), R. maidis (Fitch), and Sitobion avenae (Fab.), to a combination of host life history (annual and perennial), host provenance (native and exotic), and nutrient supply (mineral N and P fertilization), controlling for host phylogenetic lineage. Aphids consistently had higher fecundity on annual grasses than perennials, regardless of host provenance, age, or nutrient fertilization. In addition, aphids preferentially colonized annual hosts when offered a choice among host species. Multi-generation studies have found that nutrient addition affects both host quality and composition in natural communities; our experimental results indicate that the indirect effects of nutrient fertilization in determining host community composition are of more importance than are the direct effects on host quality to aphid population dynamics. To summarize the applications of our results, we demonstrate that, in contrast to the current focus on the qualitative differences between invaders and natives, the impact of invasive exotic grasses is not due to host provenance, per se, but arises because the annual invaders differ qualitatively from the native species in interactions with shared pathogen vectors. More generally, our work demonstrates the importance of isolating whether the fate and impacts of an invader are, at their root, due to the provenance of the invader, or due to other characteristics that determine its functional uniqueness in the context of the native community. PMID:19688926

Borer, Elizabeth T; Adams, Vincent T; Engler, Gareth A; Adams, Autumn L; Schumann, Canan B; Seabloom, Eric W

2009-07-01

389

Epiphyte Water Retention and Evaporation in Native and Invaded Tropical Montane Cloud Forests in Hawaii  

NASA Astrophysics Data System (ADS)

Epiphyte water retention was quantified at two montane cloud forest sites in Hawai'i Volcanoes National Park, one native and the other invaded by an alien tree species. Water storage elements measured included all epiphytic mosses, leafy liverworts, and filmy ferns. Tree surface area was estimated and a careful survey was taken to account for all epiphytes in the sample area of the forest. Samples were collected and analyzed in the lab for epiphyte water retention capacity (WRC). Based on the volume of the different kinds of epiphytes and their corresponding WRC, forest stand water retention capacity for each survey area was estimated. Evaporation from the epiphyte mass was quantified using artificial reference samples attached to trees that were weighed at intervals to determine changes in stored water on days without significant rain or fog. In addition, a soil moisture sensor was wrapped in an epiphyte sample and left in the forest for a 6-day period. Epiphyte biomass at the Native Site and Invaded Site were estimated to be 2.89 t ha-1 and 1.05 t ha-1, respectively. Average WRC at the Native Site and Invaded Site were estimated at 1.45 mm and 0.68 mm, respectively. The difference is likely due to the presence of the invasive Psidium cattleianum at the Invaded Site because its smooth stem surface is unable to support a significant epiphytic layer. The evaporation rate from the epiphyte mass near WSC for the forest stand at the Native Site was measured at 0.38 mm day-1, which represented 10.6 % of the total ET from the forest canopy at the Native Site during the period. The above research has been recently complemented by a thorough investigation of the WSC of all water storage elements (tree stems, tree leaves, shrubs, grasses, litter, fallen branches, and epiphytes) at six forested sites at different elevations within, above, and below the zone of frequent cloud-cover. The goal of this study was to create an inexpensive and efficient methodology for acquiring estimates of above-ground water retention in different types of forests by means of minimally-destructive sampling and surveying. The results of this work serve as baseline data providing a range of possible values of the water retention of specific forest elements and the entire above-ground total where no values have been previously recorded.

Mudd, R. G.; Giambelluca, T. W.

2006-12-01

390

Hedonic analysis of effects of a nonnative invader (Myriophyllum heterophyllum) on New Hampshire (USA) lakefront properties.  

PubMed

Introduced species are a major threat to the planet's ecosystems and one of the major causes of species extinction. This study deals with some of the economic impacts of one of these "invaders," variable milfoil. Variable milfoil can clog water-bodies, cause boating and swimming hazards, and crowd out native species. This study analyzed the effects of variable milfoil on shoreline property values at selected New Hampshire lakes. Results indicate that property values on lakes experiencing milfoil infestation may be considerably lower than similar properties on uninfested lakes. Results are highly sensitive to specification (variable selection) of the hedonic equation. PMID:14753624

Halstead, John M; Michaud, Jodi; Hallas-Burt, Shanna; Gibbs, Julie P

2003-09-01

391

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

NASA Astrophysics Data System (ADS)

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.

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

2011-12-01

392

Novel innate cancer killing activity in humans  

PubMed Central

Background In this study, we pilot tested an in vitro assay of cancer killing activity (CKA) in circulating leukocytes of 22 cancer cases and 25 healthy controls. Methods Using a human cervical cancer cell line, HeLa, as target cells, we compared the CKA in circulating leukocytes, as effector cells, of cancer cases and controls. The CKA was normalized as percentages of total target cells during selected periods of incubation time and at selected effector/target cell ratios in comparison to no-effector-cell controls. Results Our results showed that CKA similar to that of our previous study of SR/CR mice was present in human circulating leukocytes but at profoundly different levels in individuals. Overall, males have a significantly higher CKA than females. The CKA levels in cancer cases were lower than that in healthy controls (mean ± SD: 36.97 ± 21.39 vs. 46.28 ± 27.22). Below-median CKA was significantly associated with case status (odds ratio = 4.36; 95% Confidence Interval = 1.06, 17.88) after adjustment of gender and race. Conclusions In freshly isolated human leukocytes, we were able to detect an apparent CKA in a similar manner to that of cancer-resistant SR/CR mice. The finding of CKA at lower levels in cancer patients suggests the possibility that it may be of a consequence of genetic, physiological, or pathological conditions, pending future studies with larger sample size. PMID:21813015

2011-01-01

393

Mouse oocyte killing by neutrons: target considerations  

SciTech Connect

Highly radiosensitive primordial mouse oocytes, the principal cells at genetic risk in the female, have been studied using 0.43-MeV neutrons. Analysis of the survival curve (D/sub 37/ = 0.055 Gy) indicates that the diameter of the radiosensitive target (assumed spherical and of unit density) is larger than that of the nucleus but not of the oocyte, implicating a non-nuclear but sub-cellular target. This is consistent with results from /sup 3/H-thymidine incorporated in DNA. Our efforts to identify the extraordinarily radiosensitive lethality target in these primordial oocytes suggest it is the plasma membrane. Monte Carlo calculations for 0.43-MeV neutrons show that at the D/sub 37/ only a single proton recoil will traverse the plasma membrane, consistent with the observed exponential survival curve. A highly sensitive non-DNA target for mouse oocyte killing may importantly influence interpretations of genetic mutation data from mice and their use in estimating genetic risk in humans. 7 refs., 1 fig., 1 tab.

Straume, T.; Dobson, R.L.

1985-04-01

394

Killing, letting die and moral perception.  

PubMed

There are a number of arguments that purport to show, in general terms, that there is no difference between killing and letting die. These are used to justify active euthanasia on the basis of the reasons given for allowing patients to die. I argue that the general and abstract arguments fail to take account of the complex and particular situations which are found in the care of those with terminal illness. When in such situations, there are perceptions and intuitions available that do not easily find propositional form but lead most of those whose practice is in the care of the dying to resist active euthanasia. I make a plea for their intuitions to be heeded above the sterile voice of abstract premises and arguments by examining the completeness of the outline form of the pro-euthanasia argument. In doing so, I make use of Nussbaum's discussion of moral perception and general claims to be found in the literature of moral particularism. PMID:11654118

Gillett, Grant

1994-10-01

395

Recombinant microorganisms for increased production of organic acids  

DOEpatents

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.

Yi, Jian (East Lansing, MI); Kleff, Susanne (East Lansing, MI); Guettler, Michael V. (Holt, MI)

2012-02-21

396

Recombinant microorganisms for increased production of organic acids  

DOEpatents

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.

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

2013-04-30

397

On pseudo-Riemannian manifolds with many Killing spinors  

SciTech Connect

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.

Alekseevsky, D. V. [University of Edinburgh and Maxwell Institute for Mathematical Sciences JCMB, The King's Buildings, Edinburgh, EH9 3JZ (United Kingdom); Cortes, V. [Department Mathematik und Zentrum fuer Mathematische Physik Universitaet Hamburg, Bundesstrasse 55, D-20146 Hamburg (Germany)

2009-02-02

398

Killing vectors in asymptotically flat space-times. I. Asymptotically translational Killing vectors and the rigid positive energy theorem  

Microsoft Academic Search

We study Killing vector fields in asymptotically flat space-times. We prove the following result, implicitly assumed in the uniqueness theory of stationary black holes. If the conditions of the rigidity part of the positive energy theorem are met, then in such space-times there are no asymptotically null Killing vector fields except if the initial data set can be embedded in

Robert Beig; Piotr T. Chrusciel

1996-01-01

399

“Who Kills Whom” RevisitedA Sociological Study of Variation in the Sex Ratio of Spouse Killings  

Microsoft Academic Search

This article addresses the extraordinarily high ratio of females to males who kill domestic partners in the United States. Using a theoretical perspective conceptualizing violence between intimates as a form of self-help social control and as involving a pattern of sex-specific motives, the authors developed an explanatory model of variance in the rates of female and male spouse killing and

DeaAnn K. Gauthier; William B. Bankston

2004-01-01

400

The use of stable isotope ratio analysis to distinguish multiple prey kill events from mass kill events  

Microsoft Academic Search

Archaeologists working with prey animal bonebeds are interested in determining whether the animals were obtained through a single, mass kill event or instead accumulated over time from multiple hunting events. This is often difficult to determine. The author investigated the use of stable isotope ratio analysis to distinguish accumulations of individuals derived from multiple populations from mass kills of individuals

Jack N. Fenner

2008-01-01

401

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

SciTech Connect

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.

Maul, J.R.; Ransijn, A.; Buchmueller-Rouiller, Y. (Institute of Biochemistry, Epalinges (Switzerland))

1991-01-01

402

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

PubMed

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

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

403

Predicting how altering propagule pressure changes establishment rates of biological invaders across species pools.  

PubMed

Biological invasions resulting from international trade can cause major environmental and economic impacts. Propagule pressure is perhaps the most important factor influencing establishment, although actual arrival rates of species are rarely recorded. Furthermore, the pool of potential invaders includes many species that vary in their arrival rate and establishment potential. Therefore, we stress that it is essential to consider the size and composition of species pools arriving from source regions when estimating probabilities of establishment and effects of pathway infestation rates. To address this, we developed a novel framework and modeling approach to enable prediction of future establishments in relation to changes in arrival rate across entire species pools. We utilized 13 828 border interception records from the United States and New Zealand for 444 true bark beetle (Scolytinae) and longhorned beetle (Cerambycidae) species detected between 1949 and 2008 as proxies for arrival rates to model the relationship between arrival and establishment rates. Nonlinearity in this relationship implies that measures intended to reduce the unintended transport of potential invaders (such as phytosanitary treatments) must be highly effective in order to substantially reduce the rate of future invasions, particularly if trade volumes continue to increase. PMID:24804438

Brockerhoff, Eckehard G; Kimberley, Mark; Liebhold, Andrew M; Haack, Robert A; Cavey, Joseph F

2014-03-01

404

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

PubMed Central

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

Buric, Milos; Hulak, Martin; Kouba, Antonin

2011-01-01

405

POSSIBLE SOURCE OF SECONDARY INVADING STAPHYLOCOCCI IN MICE EXPOSED TO ACUTE COLD.  

PubMed

Miraglia, Gennaro J. (Bryn Mawr College, Bryn Mawr, Pa.) and L. Joe Berry. Possible source of secondary invading staphylococci in mice exposed to acute cold. J. Bacteriol. 85:345-348. 1963.-In an effort to determine the origin of the staphylococci known to invade the deep tissues (liver, spleen, kidneys, lungs, and heart) of mice exposed continuously to 5 C in individual compartments without bedding, the intestinal tract was freed of these organisms, as judged by absence of growth when fecal suspensions were inoculated into selective media. Substitution of 0.01 n hydrochloric acid for drinking water eliminated staphylococci within a few days, yet the incidence of tissue invasion was unaltered. The coagulase-negative strains normally present in feces and in tissues persisted in tissues even though the intestine was seeded with a coagulase-positive strain by feeding contaminated food. Cultures from the external nares continued unaltered. This suggests that the respiratory tract is a possible origin of the staphylococci found in tissues of the cold-stressed mice. PMID:16561994

Miraglia, G J; Berry, L J

1963-02-01

406

Francisella tularensis Uses Cholesterol and Clathrin-Based Endocytic Mechanisms to Invade Hepatocytes  

PubMed Central

Francisella tularensis are highly infectious microbes that cause the disease tularemia. Although much of the bacterial burden is carried in non-phagocytic cells, the strategies these pathogens use to invade these cells remains elusive. To examine these mechanisms we developed two in vitro Francisella-based infection models that recapitulate the non-phagocytic cell infections seen in livers of infected mice. Using these models we found that Francisella novicida exploit clathrin and cholesterol dependent mechanisms to gain entry into hepatocytes. We also found that the clathrin accessory proteins AP-2 and Eps15 co-localized with invading Francisella novicida as well as the Francisella Live Vaccine Strain (LVS) during hepatocyte infections. Interestingly, caveolin, a protein involved in the invasion of Francisella in phagocytic cells, was not required for non-phagocytic cell infections. These results demonstrate a novel endocytic mechanism adopted by Francisella and highlight the divergence in strategies these pathogens utilize between non-phagocytic and phagocytic cell invasion. PMID:22355707

Law, H. T.; Lin, Ann En-Ju; Kim, Youra; Quach, Brian; Nano, Francis E.; Guttman, Julian Andrew

2011-01-01

407

Francisella tularensis uses cholesterol and clathrin-based endocytic mechanisms to invade hepatocytes.  

PubMed

Francisella tularensis are highly infectious microbes that cause the disease tularemia. Although much of the bacterial burden is carried in non-phagocytic cells, the strategies these pathogens use to invade these cells remains elusive. To examine these mechanisms we developed two in vitro Francisella-based infection models that recapitulate the non-phagocytic cell infections seen in livers of infected mice. Using these models we found that Francisella novicida exploit clathrin and cholesterol dependent mechanisms to gain entry into hepatocytes. We also found that the clathrin accessory proteins AP-2 and Eps15 co-localized with invading Francisella novicida as well as the Francisella Live Vaccine Strain (LVS) during hepatocyte infections. Interestingly, caveolin, a protein involved in the invasion of Francisella in phagocytic cells, was not required for non-phagocytic cell infections. These results demonstrate a novel endocytic mechanism adopted by Francisella and highlight the divergence in strategies these pathogens utilize between non-phagocytic and phagocytic cell invasion. PMID:22355707

Law, H T; Lin, Ann En-Ju; Kim, Youra; Quach, Brian; Nano, Francis E; Guttman, Julian Andrew

2011-01-01

408

Fine-Scale Geographical Origin of an Insect Pest Invading North America  

PubMed Central

Invasive species may rapidly spread throughout new areas once introduced, which may potentially lead to serious damage to local fauna and flora. Information on geographical origins, introduction routes, and biology in native regions of such invasive species is of critical importance in identifying means of transport, preventing reintroduction, and establishing control/eradication methods. The plataspid stinkbug Megacopta cribraria, known as kudzu bug, recently invaded North America and now has become not only an agricultural pest of soybean but also a nuisance pest. Here we investigate the geographical origin of the invasive M. cribraria populations. Phylogeographical analyses based on 8.7 kb mitochondrial DNA sequences of the introduced and East Asian native Megacopta populations identified a well-supported clade consisting of the introduced populations and M. punctatissima populations in the Kyushu region of Japan, which strongly suggests that the invading M. cribraria populations are derived from a M. punctatissima population in the Kyushu region. Therefore, the region is proposed as a promising source of natural enemies for biological control of the invasive pest. Based on the phylogenetic information, relationship and treatment of the two Megacopta species are discussed. PMID:24551228

Hosokawa, Takahiro; Nikoh, Naruo; Fukatsu, Takema

2014-01-01

409

Fine-scale geographical origin of an insect pest invading North America.  

PubMed

Invasive species may rapidly spread throughout new areas once introduced, which may potentially lead to serious damage to local fauna and flora. Information on geographical origins, introduction routes, and biology in native regions of such invasive species is of critical importance in identifying means of transport, preventing reintroduction, and establishing control/eradication methods. The plataspid stinkbug Megacopta cribraria, known as kudzu bug, recently invaded North America and now has become not only an agricultural pest of soybean but also a nuisance pest. Here we investigate the geographical origin of the invasive M. cribraria populations. Phylogeographical analyses based on 8.7 kb mitochondrial DNA sequences of the introduced and East Asian native Megacopta populations identified a well-supported clade consisting of the introduced populations and M. punctatissima populations in the Kyushu region of Japan, which strongly suggests that the invading M. cribraria populations are derived from a M. punctatissima population in the Kyushu region. Therefore, the region is proposed as a promising source of natural enemies for biological control of the invasive pest. Based on the phylogenetic information, relationship and treatment of the two Megacopta species are discussed. PMID:24551228

Hosokawa, Takahiro; Nikoh, Naruo; Fukatsu, Takema

2014-01-01

410

Forecasting New Zealand Mudsnail invasion range: model comparisons using native and invaded ranges.  

PubMed

Evaluations of the potential distribution of invasive species can increase the efficiency of their management by focusing prevention measures. Generally, ecological models are built using occurrence data from a species' native range to predict the distribution in areas that the species may invade. However, historical and geographical constraints can limit a species' native distribution. Genetic Algorithm for Rule-set Production (GARP), an ecological niche modeling program, was used to predict the potential distribution of the invasive, freshwater New Zealand mudsnail, Potamopyrgus antipodarum, in Australia and North America. We compared the strength of the predictions made by models built with data from the snail's native range in New Zealand to models built with data from the locations invaded by the species. A time-series analysis of the Australian models demonstrated that range-of-invasion data can make better predictions about the potential distribution of invasive species than models built with native range data. Large differences among the model forecasts indicate that uncritical choice of the data set used in training the GARP models can result in misleading predictions. The models predict a large expansion in the range of P. antipodarum in both Australia and North America unless prevention measures are implemented rapidly. PMID:17479844

Loo, Sarina E; Mac Nally, Ralph; Lake, P S

2007-01-01

411

On Killing vector fields and Newman-Penrose constants  

NASA Astrophysics Data System (ADS)

Asymptotically flat space-times with one Killing vector field are studied. The Killing equations are solved asymptotically using polyhomogeneous expansions (i.e., series in powers of 1/r and ln r), and solved order by order. The solution to the leading terms of these expansions yields the asymptotic form of the Killing vector field. The possible classes of Killing fields are discussed by analyzing their orbits on null infinity. The integrability conditions of the Killing equations are used to obtain constraints on the components of the Weyl tensor (?0,?1,?2) and on the shear (?). The behavior of the solutions to the constraint equations is studied. It is shown that for Killing fields that are non-supertranslational the characteristics of the constraint equations are the orbits of the restriction of the Killing field to null infinity. As an application, the particular case of boost-rotation symmetric space-times is considered. The constraints on ?0 are used to study the behavior of the coefficients that give rise to the Newman-Penrose constants, if the space-time is non-polyhomogeneous, or the logarithmic Newman-Penrose constants, if the space-time is polyhomogeneous.

Kroon, Juan Antonio Valiente

2000-02-01

412

Kill a brand, keep a customer.  

PubMed

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

Kumar, Nirmalya

2003-12-01

413

Can nanomedicines kill cancer stem cells?  

PubMed

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 the 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

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

2013-11-01

414

Can Nanomedicines Kill Cancer Stem Cells?  

PubMed Central

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

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

2014-01-01

415

Did Vertigo Kill America's Forgotten Astronaut?  

NASA Technical Reports Server (NTRS)

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.

Bendrick, Gregg A.; Merlin, Peter W.

2007-01-01

416

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 ...

417

ShippingInfectious Substances, Genetically Modified Microorganisms, and Exempt Specimens  

E-print Network

ShippingInfectious Substances, Genetically Modified Microorganisms, and Exempt Specimens Goods: Biological Substances, Category B (BSCB), Genetically Modified Microorganisms (GMMO) and Exempt · Individuals wishing to ship Biological Substances Category B (BSCB) and/or Genetically Modified

Jia, Songtao

418

Investigation of Interfacial Chemistry of Microorganisms Jani C. Ingram,1  

E-print Network

Investigation of Interfacial Chemistry of Microorganisms Jani C. Ingram,1 David E. Cummings,1 Hoi in the attachment of some microorganisms to solid substrates. An impaired ability to form exopolysaccharides would

419

Investigation to identify paint coatings resistive to microorganism growth  

NASA Technical Reports Server (NTRS)

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.

Cooper, C. W.; Kemp, H. T.

1971-01-01

420

History of infection with different male-killing bacteria in the two-spot ladybird beetle Adalia bipunctata revealed through mitochondrial DNA sequence analysis.  

PubMed Central

The two-spot ladybird beetle Adalia bipunctata (Coleoptera: Coccinellidae) is host to four different intracellular maternally inherited bacteria that kill male hosts during embryogenesis: one each of the genus Rickettsia (alpha-Proteobacteria) and Spiroplasma (Mollicutes) and two distinct strains of Wolbachia (alpha-Proteobacteria). The history of infection with these male-killers was explored using host mitochondrial DNA, which is linked with the bacteria due to joint maternal inheritance. Two variable regions, 610 bp of cytochrome oxidase subunit I and 563 bp of NADH dehydrogenase subunit 5, were isolated from 52 A. bipunctata with known infection status and different geographic origin from across Eurasia. Two outgroup taxa were also considered. DNA sequence analysis revealed that the distribution of mitochondrial haplotypes is not associated with geography. Rather, it correlates with infection status, confirming linkage disequilibrium between mitochondria and bacteria. The data strongly suggest that the Rickettsia male-killer invaded the host earlier than the other taxa. Further, the male-killing Spiroplasma is indicated to have undergone a recent and extensive spread through host populations. In general, male-killing in A. bipunctata seems to represent a highly dynamic system, which should prove useful in future studies on the evolutionary dynamics of this peculiar type of symbiont-host association. PMID:11901123

v d Schulenburg, J Hinrich G; Hurst, Gregory D D; Tetzlaff, Dagmar; Booth, Gwendolen E; Zakharov, Ilia A; Majerus, Michael E N

2002-01-01

421

How could haloalkaliphilic microorganisms contribute to biotechnology?  

PubMed

Haloalkaliphiles are microorganisms requiring Na(+) concentrations of at least 0.5 mol·L(-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

Zhao, Baisuo; Yan, Yanchun; Chen, Shulin

2014-11-01

422

Characterization of Microorganisms by MALDI Mass Spectrometry  

SciTech Connect

Matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) for characterization and analysis of microorganisms, specifically bacteria, is described here as a rapid screening tool. The objective of this technique is not comprehensive protein analysis of a microorganism but rather a rapid screening of the organism and the accessible protein pattern for characterization and distinction. This method is based on the ionization of the readily accessible and easily ionizable portion of the protein profile of an organism that is often characteristic of different bacterial species. The utility of this screening approach is yet to reach its full potential but could be applied to food safety, disease outbreak monitoring in hospitals, culture stock integrity and verification, microbial forensics or homeland security applications.

Petersen, Catherine E.; Valentine, Nancy B.; Wahl, Karen L.

2008-10-02

423

BioEd Online: Lessons: Microorganisms  

NSDL National Science Digital Library

The BioEd Online site, created by the dedicated staff at the Baylor College of Medicine, is a veritable cornucopia of material for science educators. The lesson plans are all classroom tested and high-quality. This particular corner of the site focuses on the world of microorganisms. The site includes 15 lessons, complete with video clips, slideshows, and .pdf files. The offerings here include "Comparing Sizes of Microorganisms," "Observing Different Microbes," and "Microbes and Disease." The videos are quite nice as they offer a brief introduction to each subject, along with suggestions for how to conduct the associated classroom activity. If visitors enjoy these lesson plans, they should explore the other categories under Classroom Lessons, such as Animals, Genetics, and History & Nature of Science.

2012-01-01

424

Local climatic adaptation in a widespread microorganism.  

PubMed

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

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

2014-02-22

425

BioEd Online: Lessons: Microorganisms  

NSDL National Science Digital Library

The BioEd Online site, created by the dedicated staff at the Baylor College of Medicine, is a veritable cornucopia of material for science educators. The lesson plans are all classroom tested and high-quality. This particular corner of the site focuses on the world of microorganisms. The site includes lessons, complete with video clips, slideshows, and .pdf files. The offerings here include "Comparing Sizes of Microorganisms," "Observing Different Microbes," and "Microbes and Disease." The videos are quite nice as they offer a brief introduction to each subject, along with suggestions for how to conduct the associated classroom activity. If visitors enjoy these lesson plans, they should explore the other categories under Classroom Lessons, such as Animals, Genetics, and History & Nature of Science.

2012-03-02

426

A Construction of Killing Spinors on S^n  

Microsoft Academic Search

We derive simple general expressions for the explicit Killing spinors on the\\u000an-sphere, for arbitrary n. Using these results we also construct the Killing\\u000aspinors on various AdS x Sphere supergravity backgrounds, including AdS_5 x\\u000aS^5$, AdS_4 x S^7 and AdS_7 x S^4. In addition, we extend previous results to\\u000aobtain the Killing spinors on the hyperbolic spaces H^n.

H. Lu; C. N. Pope; J. Rahmfeld

1998-01-01

427

THE RATE OF KILLING OF CLADOCERANS AT HIGHER TEMPERATURES  

PubMed Central

In spite of obvious possible sources of disturbance, the "velocity of killing" of organisms at supranormal temperatures, properly determined, tends to adhere to the Arrhenius equation for relation to temperature. Over certain ranges of temperature the relationship between log velocity of killing and 1/T° abs. is linear. Interpreted as due to the thermal denaturing of protein, it is possible that differences between the temperature characteristics for the killing process in closely related forms may be suggestive in regard to the mechanism of the denaturing. The temperature limits within which the linear relationships appear may be classed among those temperature levels which are critical temperatures for protoplasmic organization. PMID:19872376

Brown, L. A.; Crozier, W. J.

1927-01-01

428

[Population organization and communication in microorganisms].  

PubMed

This review concentrates on the history of the subfield of microbiology referred to as the population organization- and communication-related research direction (POCRRD). The focal points of POCRRD include intercellular interactions, information exchange between cells, and multicellular structures (colonies, biofilms, flocs, etc.). Special attention in this review is given to the contribution of Russian scientists to the development of POCRRD. In terms of POCRRD, microorganisms are viewed as social creatures that constantly communicate and form supraorganismic, intrinsically heterogeneous systems. PMID:17025167

Oleskin, A V; Kirovskaia, T A

2006-01-01

429

Cold-Tolerant Agriculturally Important Microorganisms  

Microsoft Academic Search

\\u000a Cold-tolerant microorganisms are endowed with the ability to grow at 0°C, though their growth optima lie in the mesophilic\\u000a range. To overcome the stress induced by low temperatures they have evolved a variety of adaptive responses at the cellular\\u000a and molecular levels. Multiple cell membrane modifications ensure that solute transport is not impaired at low temperatures.\\u000a Other mechanisms include the

Pankaj Kumar Mishra; Piyush Joshi; Shekhar Bisht; Jaideep Bisht; Govindan Selvakumar

430

Monitoring genetically engineered microorganisms in freshwater microcosms  

Microsoft Academic Search

Summary The effectiveness of gene probe methods for tracking genetically engineered microorganisms (GEMs) in the environment was tested by inoculating nutrient-supplemented freshwater microcosms withAlcaligenes A5 (a naturally occurring 4-chlorobiphenyl degrader) orPseudomonas cepacia AC1100 (a genetically engineered 2, 4, 5 T-degrader) and following the fates of the introduced bacterial populations. Colony hybridization of the viable heterotrophic bacterial populations and dot blot

R. J. Steffan; A. Breen; R. M. Atlas; G. S. Sayler

1989-01-01

431

The transfer of viable microorganisms between planets.  

PubMed

There is increasing acceptance that catastrophic cosmic impacts have played an important role in shaping the history of terrestrial life. Large asteroid and cometary impacts are also capable of displacing substantial quantities of planetary surface material into space. The discovery of Martian rocks on Earth suggests that viable microorganisms within such ejecta could be exchanged between planets. If this conjecture is correct, it will have profound implications for the origin and evolution of life in the solar system. PMID:9243022

Davies, P C

1996-01-01

432

Clustering of gyrotactic microorganisms in turbulent flows  

E-print Network

We study the spatial distribution of gyrotactic microorganisms transported by a three-dimensional turbulent flow generated by direct numerical simulations. We find that gyrotaxis combines with turbulent fluctuations to produce small scales (multi-)fractal clustering. We explain this result by showing that gyrotactic swimming cells behave like tracers in a compressible flow. The effective compressibility is derived in the limits of fluid acceleration much larger and smaller than the gravity.

Filippo De Lillo; Guido Boffetta; Massimo Cencini

2012-06-12

433

How do microorganisms reach the stratosphere?  

NASA Astrophysics Data System (ADS)

A number of studies have demonstrated that bacteria and fungi are present in the stratosphere. Since the tropopause is generally regarded as a barrier to the upward movement of particles it is difficult to see how such microorganisms can reach heights above 17 km. Volcanoes provide an obvious means by which this could be achieved, but these occur infrequently and any microorganisms entering the stratosphere from this source will rapidly fall out of the stratosphere. Here, we suggest mechanisms by which microorganisms might reach the stratosphere on a more regular basis; such mechanisms are, however, likely only to explain how micrometre to submicrometre particles could be elevated into the stratosphere. Intriguingly, clumps of bacteria of size in excess of 10 ?m have been found in stratospheric samples. It is difficult to understand how such clumps could be ejected from the Earth to this height, suggesting that such bacterial masses may be incoming to Earth. We suggest that the stratospheric microflora is made up of two components: (a) a mixed population of bacteria and fungi derived from Earth, which can occasionally be cultured; and (b) a population made up of clumps of, viable but non-culturable, bacteria which are too large to have originated from Earth; these, we suggest, have arrived in the stratosphere from space. Finally, we speculate on the possibility that the transfer of bacteria from the Earth to the highly mutagenic stratosphere may have played a role in bacterial evolution.

Wainwright, M.; Alharbi, S.; Wickramasinghe, N. C.

2006-04-01

434

Endodontic microorganism susceptibility by direct contact test.  

PubMed

The aim of this study was to evaluate in vitro the duration of the antimicrobial effect of endodontic sealers by means of the Direct Contact Test. The sealers tested were: Endomethasone - Septodont, Endomethasone C-Septodont, Endion-Voco, Diaket-ESPE, Pulp Canal Sealer-SybronEndo, and AH26-Dentsply DeTrey. The endodontopathic microorganisms (MO) confronted were: Staphylococcus aureus (Sa), Candida albicans (Ca), Enterococcus faecalis (Ef), Prevotella intermedia (Pi), Porphyromonas gingivalis (Pg) and Fusobacterium nucleatum (Fn). Test specimens of each sealer were prepared and placed on the surface of agar plates that had been inoculated with each MO, and after predetermined periods, transfers were made from the contact area between the test specimen and the cultured agar and from the area that had not been in contact with the test specimens (control). The results were read as presence/absence of microbial growth and analyzed statistically using the Kruskal-Wallis test. It was concluded that the structural features and virulence of endodontopathic microorganisms determine their response to the sealers, independently of the time during which sealers act and the mechanism by which the antiseptic reaches the microorganism, which in this case was by direct contact. PMID:19177855

Pérez, Sandra B; Tejerina, Denise P; Pérez Tito, Romina I; Bozza, Florencia L; Kaplan, Andrea E; Molgatini, Susana L

2008-01-01

435

Interactions of Soil Minerals with Organic Components and Microorganisms  

Microsoft Academic Search

Minerals, organic matter and microorganisms of the pedosphere are the key factors necessary for soil formation (pedogenesis) and other soil processes (1). The mineral composition of soil is a major part of the ecology of microorganisms. Interaction of soil minerals with microorganisms affects the metabolic transformation of natural and xenobiotic organic compounds and the fate of metals and other inorganic

BOLLAG Jean-Marc; LEYVAL Corinne

436

In Situ Survival of Genetically Engineered Microorganisms in a Tropical  

E-print Network

In Situ Survival of Genetically Engineered Microorganisms in a Tropical Aquatic Environment A. J & Sons, Inc. INTRODUCTION An accidental or deliberate release of genetically engi- neered microorganisms of their manipulated DNA to other microorganisms. Prediction of the fate of the GEMs and their engineered DNA

Hazen, Terry

437

Polycyclic Aromatic Hydrocarbon Degrading Microorganisms in Great Lakes Sediments  

Microsoft Academic Search

Biodegradation is a chemical transformation process that may result in the decontamination of sediments. A criterion for the potential success of biode gradation is the ability of indigenous microorganisms to catabolize contaminants, such as polycyclic aromatic hydrocarbons (PAHs). The number of microorganisms displaying this ability may be influenced by the extent of their exposure to PAHs. In this study, microorganisms

Dan L. McNally; James R. Mihelcic; Donald R. Lueking

1998-01-01

438

Isolation of microorganisms for biological detoxification of lignocellulosic hydrolysates  

Microsoft Academic Search

Acid pretreatment of lignocellulosic biomass releases furan and phenolic compounds, which are toxic to microorganisms used for subsequent fermentation. In this study, we isolated new microorganisms for depletion of inhibitors in lignocellulosic acid hydrolysates. A sequential enrichment strategy was used to isolate microorganisms from soil. Selection was carried out in a defined mineral medium containing a mixture of ferulic acid

M. J. López; N. N. Nichols; B. S. Dien; J. Moreno; R. J. Bothast

2004-01-01

439

Original article Prevalence of microorganisms in dead mink kits  

E-print Network

Original article Prevalence of microorganisms in dead mink kits from Aleutian% were fungi. The prevalence of microorganisms appeared less common in kits from AD-non-infected farms was the most highly infected site in both groups and generally was only infected by one microorganism species

Paris-Sud XI, Université de

440

Force Sensing for the Identification of Single-Cell Microorganisms*  

E-print Network

Force Sensing for the Identification of Single-Cell Microorganisms* A. S. Lee, M. Mahapatro, A. A for detecting microorganisms that cannot be identified by optical microscopy. Experimental results are presented for the identification of Brown Tide Algae, which are single- cell marine microorganisms with dimensions on the order

Southern California, University of

441

Physics 3, 84 (2010) A quantitative look into microorganism hydrodynamics  

E-print Network

Physics 3, 84 (2010) Viewpoint A quantitative look into microorganism hydrodynamics David swimming microorganisms is more complex than previ- ously thought, with important implications for how of the Flow Field around Swimming Microorganisms Knut Drescher, Raymond E. Goldstein, Nicolas Michel, Marco

Bou-Zeid, Elie

442

40 CFR 725.67 - Applications to exempt new microorganisms from this part.  

Code of Federal Regulations, 2012 CFR

... Applications to exempt new microorganisms from this part. 725.67...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Administrative Procedures... Applications to exempt new microorganisms from this part. (a)...

2012-07-01

443

40 CFR 725.67 - Applications to exempt new microorganisms from this part.  

Code of Federal Regulations, 2011 CFR

... Applications to exempt new microorganisms from this part. 725.67...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Administrative Procedures... Applications to exempt new microorganisms from this part. (a)...

2011-07-01

444

40 CFR 725.67 - Applications to exempt new microorganisms from this part.  

Code of Federal Regulations, 2013 CFR

... Applications to exempt new microorganisms from this part. 725.67...REQUIREMENTS AND REVIEW PROCESSES FOR MICROORGANISMS Administrative Procedures... Applications to exempt new microorganisms from this part. (a)...

2013-07-01

445

Order of inoculation affects the success of co-invading entomopathogenic fungi.  

PubMed

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

Zamora-Macorra, E J; Guzmán-Franco, A W; Pell, J K; Alatorre-Rosas, R; Suarez-Espinoza, J

2012-12-01

446

PFIESTERIA SHUMWAYAE KILLS FISH BY MICROPREDATION NOT ECOTOXIN SECRETION  

EPA Science Inventory

Massive fish kills in mid-Atlantic USA estuaries involving several million Atlantic menhaden, Brevoortia tyrannus,have been attributed to dinoflagellates of the toxic Pfiesteria complex (TPC). Potent ichthyotoxins secreted during Pfiesteria blooms are thought to be responsible fo...

447

7 CFR 29.1018 - Fire-killed.  

Code of Federal Regulations, 2010 CFR

...AGRICULTURE COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS TOBACCO INSPECTION Standards Official Standard Grades for Flue-Cured Tobacco (u.s. Types 11, 12, 13, 14 and Foreign Type 92) § 29.1018 Fire-killed. Any leaf of...

2010-01-01

448

Surface structure influences contact killing of bacteria by copper  

PubMed Central

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

Zeiger, Marco; Solioz, Marc; Edongué, Hervais; Arzt, Eduard; Schneider, Andreas S

2014-01-01

449

Killing superalgebra deformations of ten-dimensional supergravity backgrounds  

NASA Astrophysics Data System (ADS)

We explore Lie superalgebra deformations of the Killing superalgebras of some ten-dimensional supergravity backgrounds. We prove the rigidity of the Poincaré superalgebras in types I, IIA and IIB, as well as of the Killing superalgebra of the Freund Rubin vacuum of type IIB supergravity. We also prove rigidity of the Killing superalgebras of the NS5-, D0-, D3-, D4- and D5-branes, whereas we exhibit the possible deformations of the D1-, D2-, D6- and D7-brane Killing superalgebras, as well as of that of the type II fundamental string solutions. We relate the superalgebra deformations of the D2- and D6-branes to those of the (delocalized) M2-brane and the Kaluza Klein monopole, respectively. The good behaviour under Kaluza Klein reduction suggests that the deformed superalgebras ought to have a geometric interpretation.

Figueroa-O'Farrill, José; Vercnocke, Bert

2007-12-01

450

Scientists Report New Lead in How Anthrax Kills Cells  

Cancer.gov

For years scientists have known that anthrax bacillus produces a toxin containing a deadly protein called lethal factor. However, researchers have never been able to identify how lethal factor kills cells.

451

Flat deformation of a spacetime admitting two commuting Killing fields  

NASA Astrophysics Data System (ADS)

It is shown that, given an analytic Lorentzian metric on a 4-manifold, gab, which admits two Killing vector fields, there exists a local deformation law ?ab = a gab + b Hab, where Hab is a two-dimensional projector, such that ?ab is flat and admits the same Killing vectors. We also characterize the particular case when the projector Hab coincides with the quotient metric. We apply some of our results to general stationary axisymmetric spacetimes.

Llosa, Josep; Carot, Jaume

2010-12-01

452

On the infinitesimal isometries of manifolds with Killing spinors  

Microsoft Academic Search

We study the Lie algebra of infinitesimal isometries of seven-dimensional simply connected manifolds with Killing spinors. We obtain some splitting theorems for the action of this algebra on the space of Killing spinors, and as a corollary we prove that there is no infinitesimal isometry of constant length on a seven-dimensional 3-Sasakian manifold (not isometric to a space form) except

Andrei Moroianu

2000-01-01

453

Approximate Killing vectors on S{sup 2}  

SciTech Connect

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.

Cook, Gregory B. [Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27006 (United States); Whiting, Bernard F. [Department of Physics, University of Florida, Gainesville, Florida 32611 (United States)

2007-08-15

454

Life History Traits of the Invader Dikerogammarus villosus (Crustacea: Amphipoda) in the Moselle River, France  

NASA Astrophysics Data System (ADS)

The latest threatening invader in European freshwaters is Dikerogammarus villosus, a large gammarid of Ponto-Caspian origin exhibiting a predatory behaviour. Its biology and population dynamics were studied over a one-year period in a recipient ecosystem to determine bio/ecological traits having facilitated its rapid establishment. The study revealed that D. villosus reaches sexual maturity early, at six mm in length, and produces three reproductive peaks, though the species reproduces all year long, hence reflecting its multivoltine character. The study also revealed a female-biased sex ratio, exceptional growth rates of up to 2.6 mm in two-weeks in spring, and one of the highest fecundities of Western Europe gammarids. D. villosus exhibits a biological profile suggesting that only a few individuals can rapidly establish a new population in a recipient ecosystem, and allow this gammarid to become cosmopolitan in the near future. (

Devin, Simon; Piscart, Christophe; Beisel, Jean-Nicolas; Moreteau, Jean-Claude

2004-01-01

455

Chemical warfare among invaders: a detoxification interaction facilitates an ant invasion.  

PubMed

As tawny crazy ants (Nylanderia fulva) invade the southern United States, they often displace imported fire ants (Solenopsis invicta). After exposure to S. invicta venom, N. fulva applies abdominal exocrine gland secretions to its cuticle. Bioassays reveal that these secretions detoxify S. invicta venom. Further, formic acid from N. fulva venom is the detoxifying agent. N. fulva exhibits this detoxification behavior after conflict with a variety of ant species; however, it expresses it most intensely after interactions with S. invicta. This behavior may have evolved in their shared South American native range. The capacity to detoxify a major competitor's venom probably contributes substantially to its ability to displace S. invicta populations, making this behavior a causative agent in the ecological transformation of regional arthropod assemblages. PMID:24526314

Lebrun, Edward G; Jones, Nathan T; Gilbert, Lawrence E

2014-02-28

456

Atypical esthesioneuroblastoma invading oral cavity: a case report and review of the literature  

PubMed Central

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

2014-01-01

457

Analysis of the theoretical model of drilling fluid invading into oceanic gas hydrates-bearing sediment  

NASA Astrophysics Data System (ADS)

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

Zhang, L.; Ning, F.; Jiang, G.; Wu, N.; Wu, D.

2009-12-01

458

Aortic Periannular Abscess Invading into the Central Fibrous Body, Mitral Valve, and Tricuspid Valve  

PubMed Central

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.

Oh, Hyun Kong; Kim, Nan Yeol; Kang, Min-Woong; Kang, Shin Kwang; Yu, Jae Hyeon; Lim, Seung Pyung; Choi, Jae Sung; Na, Myung Hoon

2014-01-01

459

Spinorial geometry and Killing spinor equations of 6-D supergravity  

E-print Network

We solve the Killing spinor equations of 6-dimensional (1,0)-supergravity coupled to any number of tensor, vector and scalar multiplets in all cases. The isotropy groups of Killing spinors are $Sp(1)\\cdot Sp(1)\\ltimes \\bH (1)$, $U(1)\\cdot Sp(1)\\ltimes \\bH (2)$, $Sp(1)\\ltimes \\bH (3,4)$, $Sp(1) (2)$, $U(1) (4)$ and $\\{1\\} (8)$, where in parenthesis is the number of supersymmetries preserved in each case. If the isotropy group is non-compact, the spacetime admits a parallel null 1-form with respect to a connection with torsion the 3-form field strength of the gravitational multiplet. The associated vector field is Killing and the 3-form is determined in terms of the geometry of spacetime. The $Sp(1)\\ltimes \\bH$ case admits a descendant solution preserving 3 out of 4 supersymmetries due to the hyperini Killing spinor equation. If the isotropy group is compact, the spacetime admits a natural frame constructed from 1-form spinor bi-linears. In the $Sp(1)$ and U(1) cases, the spacetime admits 3 and 4 parallel 1-forms with respect to the connection with torsion, respectively. The associated vector fields are Killing and under some additional restrictions the spacetime is a principal bundle with fibre a Lorentzian Lie group. The conditions imposed by the Killing spinor equations on all other fields are also determined.

Mehmet Akyol; George Papadopoulos

2010-10-13

460

Spinorial geometry and Killing spinor equations of 6D supergravity  

NASA Astrophysics Data System (ADS)

We solve the Killing spinor equations of six-dimensional (1, 0)-supergravity coupled to any number of tensor, vector and scalar multiplets in all cases. The isotropy groups of Killing spinors are Sp(1)\\cdot Sp(1)\\ltimes {\\bb H}(1), U(1)\\cdot Sp(1)\\ltimes {\\bb H}(2), Sp(1)\\ltimes {\\bb H}(3,4), Sp(1)(2), U(1)(4) and {1}(8), where in parenthesis is the number of supersymmetries preserved in each case. If the isotropy group is non-compact, the spacetime admits a parallel null 1-form with respect to a connection with torsion given by the 3-form field strength of the gravitational multiplet. The associated vector field is Killing and the 3-form is determined in terms of the geometry of spacetime. The Sp(1)\\ltimes {\\bb H} case admits a descendant solution preserving three out of four supersymmetries due to the hyperini Killing spinor equation. If the isotropy group is compact, the spacetime admits a natural frame constructed from 1-form spinor bi-linears. In the Sp(1) and U(1) cases, the spacetime admits three and four parallel 1-forms with respect to the connection with torsion, respectively. The associated vector fields are Killing and under some additional restrictions the spacetime is a principal bundle with fibre a Lorentzian Lie group. The conditions imposed by the Killing spinor equations on all other fields are also determined.

Akyol, M.; Papadopoulos, G.

2011-05-01

461

Grassland invaders and their mycorrhizal symbionts: a study across climate and invasion gradients  

PubMed Central

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

Bunn, Rebecca A; Lekberg, Ylva; Gallagher, Christopher; Rosendahl, S?ren; Ramsey, Philip W

2014-01-01

462

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

PubMed

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

Parnell, S; Gottwald, T R; Riley, T; van den Bosch, F

2014-06-01

463

The Anomalous Diffusion of a Tumor Invading with Different Surrounding Tissues  

PubMed Central

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

Jiang, Chongming; Cui, Chunyan; Li, Li; Shao, Yuanzhi

2014-01-01

464

Differences in ecological structure, function, and native species abundance between native and invaded Hawaiian streams.  

PubMed

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

Holitzki, Tara M; MacKenzie, Richard A; Wiegner, Tracy N; McDermid, Karla J

2013-09-01

465

Grassland invaders and their mycorrhizal symbionts: a study across climate and invasion gradients.  

PubMed

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

Bunn, Rebecca A; Lekberg, Ylva; Gallagher, Christopher; Rosendahl, Søren; Ramsey, Philip W

2014-03-01

466

Prognosis of Curatively Resected pT4b Gastric Cancer with Respect to Invaded Organ Type  

Microsoft Academic Search

Purpose  Curative resection, including gastrectomy, extensive lymph node dissection, and combined resection of invaded organs, is the\\u000a mainstay of treatment for T4b gastric cancers. We sought to investigate the clinicopathologic features, surgical outcomes,\\u000a and prognostic factors of curatively resected pathologic T4b gastric cancer with a focus on organs invaded.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Data of 243 pT4b gastric cancer patients who underwent curative resection at

Jae-Seok Min; Sung-Ho Jin; Sang-Bum Kim; Ho-Yoon Bang; Jong-Inn Lee

467

Targeted Killing and Just War: Reconciling Kill-Capture Missions, International Law, and the Combatant Civilian Framework  

Microsoft Academic Search

This paper addresses how kill-capture missions can be reconciled with the underlying principles of just war theory. Part I of this paper outlines the traditional just war combatant-civilian framework and the basic legal doctrines currently thought to apply to targeted killing. Part II advances a new conception of the traditional combatant-civilian framework that incorporates the third category of alternative belligerents

Louis H. Guard

2012-01-01

468

Extremophilic microorganisms as candidates for extraterrestrial life  

NASA Astrophysics Data System (ADS)

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.

Seckbach, Joseph; Oren, Aharon

2000-12-01

469

Resistance of soil microorganisms to starvation.  

NASA Technical Reports Server (NTRS)

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.

Chen, M.; Alexander, M.

1972-01-01

470

Green biosynthesis of floxuridine by immobilized microorganisms.  

PubMed

This work describes an efficient, simple, and green bioprocess for obtaining 5-halogenated pyrimidine nucleosides from thymidine by transglycosylation using whole cells. Biosynthesis of 5-fluoro-2'-deoxyuridine (floxuridine) was achieved by free and immobilized Aeromonas salmonicida ATCC 27013 with an 80% and 65% conversion occurring in 1 h, respectively. The immobilized biocatalyst was stable for more than 4 months in storage conditions (4 °C) and could be reused at least 30 times without loss of its activity. This microorganism was able to biosynthesize 2.0 mg L(-1) min(-1) (60%) of 5-chloro-2'-deoxyuridine in 3 h. These halogenated pyrimidine 2'-deoxynucleosides are used as antitumoral agents. PMID:22428623

Rivero, Cintia W; Britos, Claudia N; Lozano, Mario E; Sinisterra, Jose V; Trelles, Jorge A

2012-06-01

471

Engineering photosynthesis in plants and synthetic microorganisms.  

PubMed

Photosynthetic organisms, such as cyanobacteria, algae, and plants, sustain life on earth by converting light energy, water, and CO(2) into chemical energy. However, due to global change and a growing human population, arable land is becoming scarce and resources, including water and fertilizers, are becoming exhausted. It will therefore be crucial to design innovative strategies for sustainable plant production to maintain the food and energy bases of human civilization. Several different strategies for engineering improved photosynthesis in crop plants and introducing novel photosynthetic capacity into microorganisms have been reviewed. PMID:23028016

Maurino, Veronica G; Weber, Andreas P M

2013-01-01

472

Mixing by microorganisms in stratified fluids  

E-print Network

We examine the vertical mixing induced by the swimming of microorganisms at low Reynolds and P\\'eclet numbers in a stably stratified ocean, and show that the global contribution of oceanic microswimmers to vertical mixing is negligible. We propose two approaches to estimating the mixing efficiency, $\\eta$, or the ratio of the rate of potential energy creation to the total rate-of-working on the ocean by microswimmers. The first is based on scaling arguments and estimates $\\eta$ in terms of the ratio between the typical organism size, $a$, and an intrinsic length scale for the stratified flow, $\\ell = \\left ( \

Wagner, Gregory L; Lauga, Eric

2014-01-01

473

Temperature response of Antarctic cryptoendolithic photosynthetic microorganisms  

NASA Technical Reports Server (NTRS)

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.

Ocampo-Friedmann, R.; Meyer, M. A.; Chen, M.; Friedmann, E. I.

1988-01-01

474

Microorganisms and biomolecules in space hard environment  

NASA Technical Reports Server (NTRS)

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.

Horneck, G.

1981-01-01

475

Studies on the kinetics of killing and the proposed mechanism of action of microemulsions against fungi.  

PubMed

Microemulsions are physically stable oil/water clear dispersions, spontaneously formed and thermodynamically stable. They are composed in most cases of water, oil, surfactant and cosurfactant. Microemulsions are stable, self-preserving antimicrobial agents in their own right. The observed levels of antimicrobial activity associated with microemulsions may be due to the direct effect of the microemulsions themselves on the bacterial cytoplasmic membrane. The aim of this work is to study the growth behaviour of different microbes in presence of certain prepared physically stable microemulsion formulae over extended periods of time. An experiment was designed to study the kinetics of killing of a microemulsion preparation (17.3% Tween-80, 8.5% n-pentanol, 5% isopropyl myristate and 69.2% sterile distilled water) against selected test microorganisms (Candida albicans, Aspergillus niger, Schizosaccharomyces pombe and Rhodotorula spp.). Secondly, an experiment was designed to study the effects of the microemulsion preparation on the cytoplasmic membrane structure and function of selected fungal species by observation of 260 nm component leakage. Finally, the effects of the microemulsion on the fungal membrane structure and function using S. pombe were studied using transmission electron microscopy. The results showed that the prepared microemulsions are stable, effective antimicrobial systems with effective killing rates against C. albicans, A. niger, S. pombe and Rhodotorula spp. The results indicate a proposed mechanism of action of significant anti-membrane activity, resulting in the gross disturbance and dysfunction of the cytoplasmic membrane structure which is followed by cell wall modifications, cytoplasmic coagulation, disruption of intracellular metabolism and cell death. PMID:23830945

Al-Adham, Ibrahim S I; Ashour, Hana; Al-Kaissi, Elham; Khalil, Enam; Kierans, Martin; Collier, Phillip J

2013-09-15

476

DIALYSIS FLASK FOR CONCENTRATED CULTURE OF MICROORGANISMS  

PubMed Central

Gerhardt, Philipp (The University of Michigan, Ann Arbor), and D. M. Gallup. Dialysis flask for concentrated culture of microorganisms. J. Bacteriol 86:919–929. 1963.—A twin-chambered dialysis flask was designed with a supported membrane clamped between a reservoir of medium in the bottom and a small volume of culture above, the unit being mounted on a shaking machine to provide aeration and agitation. The performance of different dialysis membranes and membrane filters was compared in glucose-diffusion and bacterial-culture tests. Some of the variables in dialysis culture were assessed and the growth response was characterized, with Serratia marcescens as the test organism. The general usefulness and concentrating effect of dialysis culture were demonstrated in trials with 16 representative types of microorganisms. Dialysis culture was shown to be especially suitable for producing dense populations of cells or their macromolecular products in an environment free from complex medium constituents, for removing toxic products that limit growth or fermentation, and for supplying oxygen by diffusion without the damage from usual aeration procedures. Images PMID:14080802

Gerhardt, Philipp; Gallup, D. M.

1963-01-01

477

[Sensitivity of surface microorganisms to disinfectants].  

PubMed

The influence of humidity and temperature on survival of S. aureus and P. aeruginosa on the surfaces of titles, glass and blanket carriers has been estimated. The number of CFU was examined after exposure time 6 and 24 hours in temperatures of 21 degrees C, 37 degrees C and RH 35%, 95%. It was observed: 1. The important reduction of numbers of both microorganisms at temperature 37 degrees C and RH 95%, 2. The relatively high number of survival cells of P. aeruginosa on the surface of blankets at temp. 21 degrees C and RH 95%. The microorganisms on the carriers were previously kept for 24 h at temp. 21 degrees C, RH 35% and 95% and then exposed to solutions of chloramine, formalin, lysol and Sterinol (QAC). It was observed that there was a great dependence of the disinfecting effect on the degree of dessication of the surfaces. In all cases the resistance of contaminated carriers stored 24 h was higher at 95% RH than at 35% RH. PMID:1788516

Krzywicka, H; Janowska, J; Tadeusiak, B

1991-01-01

478

Dynamics of microorganisms with autochemotactic interactions  

NASA Astrophysics Data System (ADS)

Our work aims at the description of the early stage of bacterial biofilm formation. In light of this, we model bacteria as self-propelled particles that move on a surface with constant speed and whose directions of motion diffuse on the unit circle. Individual cells communicate by autochemotaxis, so they follow the gradient of a chemical which is produced by the microorganisms themselves. We investigate how the autochemotactic coupling influences the mean squared displacement of a single particle and show that the long-time dynamics is diffusive. We present theoretical predictions for the diffusion coefficient and compare them to numerical results. To incorporate the size of bacteria, we model them as disks that experience a harmonic repulsion force when they start to overlap. Our repulsion mechanism for particles in contact assumes a linear relationship between force and velocity. For such a soft model microorganism, we present numerical results on two-particle collisions and study the cluster formation in a multi-particle system.

Taktikos, Johannes; Zaburdaev, Vasily; Stark, Holger

2011-03-01

479

Directed Culturing of Microorganisms Using Metatranscriptomics  

PubMed Central

The vast majority of bacterial species remain uncultured, and this severely limits the investigation of their physiology, metabolic capabilities, and role in the environment. High-throughput sequencing of RNA transcripts (RNA-seq) allows the investigation of the diverse physiologies from uncultured microorganisms in their natural habitat. Here, we report the use of RNA-seq for characterizing the metatranscriptome of the simple gut microbiome from the medicinal leech Hirudo verbana and for utilizing this information to design a medium for cultivating members of the microbiome. Expression data suggested that a Rikenella-like bacterium, the most abundant but uncultured symbiont, forages on sulfated- and sialated-mucin glycans that are fermented, leading to the secretion of acetate. Histological stains were consistent with the presence of sulfated and sialated mucins along the crop epithelium. The second dominant symbiont, Aeromonas veronii, grows in two different microenvironments and is predicted to utilize either acetate or carbohydrates. Based on the metatranscriptome, a medium containing mucin was designed, which enabled the cultivation of the Rikenella-like bacterium. Metatranscriptomes shed light on microbial metabolism in situ and provide critical clues for directing the culturing of uncultured microorganisms. By choosing a condition under which the desired organism is rapidly proliferating and focusing on highly expressed genes encoding hydrolytic enzymes, binding proteins, and transporters, one can identify an organism’s nutritional preferences and design a culture medium. PMID:21467263

Bomar, Lindsey; Maltz, Michele; Colston, Sophie; Graf, Joerg

2011-01-01

480

Chemosensing in microorganisms to practical biosensors  

E-print Network

Microorganisms like bacteria can sense concentration of chemo-attractants in its medium very accurately. They achieve this through interaction between the receptors on their cell surface and the chemo-attractant molecules (like sugar). But the physical processes like diffusion set some limits on the accuracy of detection which was discussed by Berg and Purcell in the late seventies. We have a re-look at their work in order to assess what insight it may offer towards making efficient, practical biosensors. We model the functioning of a typical biosensor as a reaction-diffusion process in a confined geometry. Using available data first we characterize the system by estimating the kinetic constants for the binding/unbinding reactions between the chemo-attractants and the receptors. Then we compute the binding flux for this system which Berg and Purcell had discussed. But unlike in microorganisms where the interval between successive measurements determines the efficiency of the nutrient searching process, it turns out that biosensors depend on long time properties like signal saturation time which we study in detail. We also develop a mean field description of the kinetics of the system.

Surya K. Ghosh; Tapanendu Kundu; Anirban Sain

2012-03-28

481

When fish die, bacteria or the enzymes they produce invade the flesh of fish. This process produces toxic  

E-print Network

ABSTRACT When fish die, bacteria or the enzymes they produce invade the flesh of fish. This process produces toxic compounds in the fish and the fish becomes spoiled. Fourier Transform Infrared spectroscopy neural network (ANN) for the development of an ANN based FT-IR Screening System for fish

Michel, Howard E.

482

Population development of the invader ctenophore Mnemiopsis leidyi , in the Black Sea and in other seas of the Mediterranean basin  

Microsoft Academic Search

In the last two decades of the twentieth century, the ctenophore Mnemiopsis leidyi (A. Agassiz) has invaded the Black, Azov, Marmara and Aegean Seas, and, recently, the Caspian Sea. Here, we compare its spatial and temporal distribution, seasonal dynamics and the time and duration of reproduction. We also discuss factors that control its abundance throughout its invasive range and its

T. Shiganova; Z. Mirzoyan; E. Studenikina; S. Volovik; I. Siokou-Frangou; S. Zervoudaki; E. Christou; A. Skirta; H. Dumont

2001-01-01

483

Like a stealth invader, a disease-causing bacterium strikes where plants are weakest. By following the bacterium  

E-print Network

Like a stealth invader, a disease-causing bacterium strikes where plants are weakest. By following' defenses against a broad range of diseases. James Alfano, Charles Bessey Professor of Plant Pathology, studies Pseudomonas syringae, a bacterial pathogen that disables a plant's immune response by using

484

[Parasites-invaders of the Volga river basin: history of invasion, perspective of dispersion, possibility of epizootic].  

PubMed

The fauna of fish parasites in the Volga river increased by 15 species in last time. These parasites have invaded together with introduced hosts or dispersed after destruction of some physical and ecological barriers. The infusoria Ambiphrya ameuri, cestode Cestobothrium acheilognathi, trematodes Amurotrema dombrovskajae and Sanguinicola skrabini have been introduced together with their hosts. A creation of water reservoirs destroyed ecological barriers and created favorable conditions for the migration and dispersion of parasites. The cestodes Eubothrium rugosum, Proteocephalus longicollis, and nematode Cystidicola farionis migrated from the North, Aspidogaster limacoides migrated from the South. The leech Caspiobdella fadejevi, trematodes Rossicotrema donicus, Apophallus muehlingi, Niccola skrjabini, Plagioporus skrjabini migrated through the Volga-Don channel. Some invader have already finished their dispersion in the water reservoirs of Volga river, other parasites still continue this process. South border of the E. rugosum range is in the Kujbyshev water basin, the leech C. fadejevi is distributed in all water basins, trematodes R. donicus, A. muehlingi and P. skrjabini are found in the Volga delta, while N. skrjabini has already reached the Saratov water basin. Perspectives of new invaders and epizootic significance of invaders is discussed. PMID:11558337

Zhokhov, A E; Pugacheva, M N

2001-01-01

485

Native, insect herbivore communities derive a significant proportion of their carbon from a widespread invader of forest understories  

Microsoft Academic Search

Research on natural enemies demon- strates the potential for exotic plants to be integrated into foodwebs through the activities of native herbi- vores. The quantitative importance of exotics as a food resource to herbivores is more difficult to ascertain. In addition, some widespread invaders appear to have minimal herbivore loads. Microste- gium vimineum is one example. It is an annual,

INVASION N OTE; Mark A. Bradford; Jayna L. DeVore; John C. Maerz; Joseph V. McHugh; Cecil L. Smith; Michael S. Strickland

2009-01-01

486

Geographic and between-generation variation in the parasitoid communities associated with an invading gallwasp, Andricus quercuscalicis (Hymenoptera: Cynipidae)  

Microsoft Academic Search

The knopper gallwasp Andricus quercuscalicis Burgsdorf 1783 (Hymenoptera: Cynipidae) has invaded western and northern Europe from southern and eastern Europe over the last 400 years. A. quercuscalicis has two alternating generations, which differ in phenology, structure, and host oak species. This study describes geographic variation in the community in the tiny catkin galls of the sexual generation on Turkey oak,

Graham N. Stone; Karsten Schönrogge; Michael J. Crawley; Simon Fraser

1995-01-01

487

Abstract While interactions between invaders and resi-dent species have received a great deal of attention re-  

E-print Network

considered. We investigated the reproductive ecology of two closely related, woody le- gumes, Cytisus scoparius (Scotch broom) and Genista monspessulana (French broom), invading the same sites. Both species has much smaller flowers than Cytisus. Nei- ther species showed appreciable levels of autogamous

Brown, Cynthia S.

488

43 CFR 3873.3 - Non-mineral entry of residue of subdivisions invaded by mining claims.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Non-mineral entry of residue of subdivisions invaded...MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) ADVERSE CLAIMS...CONFLICTS Segregation § 3873.3 Non-mineral entry of residue of subdivisions...

2011-10-01

489

Naturalized plants have smaller genomes than their non-invading relatives: a flow cytometric analysis of the Czech alien flora  

E-print Network

analysis of the Czech alien flora Naturalizované rostliny mají mensí genom nez neinvadující druhy than their non-invading relatives: a flow cytometric analysis of the Czech alien flora. ­ Preslia 82 in 93 alien species naturalized in the Czech Republic, belonging to 32 families, by using flow cytometry

Kratochvíl, Lukas

490

Honor killing attitudes amongst adolescents in Amman, Jordan.  

PubMed

The present study examines attitudes towards honor crimes amongst a sample of 856 ninth grade students (mean age?=?14.6, SD?=?0.56) from 14 schools in Amman, Jordan. Descriptive findings suggest that about 40% of boys and 20% of girls believe that killing a daughter, sister, or wife who has dishonored the family can be justified. A number of theoretically meaningful predictors were examined: Findings suggest that attitudes in support of honor killings are more likely amongst adolescents who have collectivist and patriarchal world views, believe in the importance of female chastity amongst adolescents, and morally neutralize aggressive behavior in general. Findings for parental harsh discipline are mixed: While the father's harsh discipline is predictive of honor killing attitudes, the mother's behavior is not. Furthermore, support for honor killing is stronger amongst male adolescents and adolescents for low education backgrounds. After controlling for other factors religion and the intensity of religious beliefs are not associated with support for honor killings. Models were tested separately for male and female respondents and suggested no systematic differences in predictors. Limitations and implications are discussed. PMID:23744567

Eisner, Manuel; Ghuneim, Lana

2013-01-01

491

July/August 2012 Newsletter Subscriptions Bee-Kill Survey USDA APHIS Survey Canadian Nosema Studies  

E-print Network

to their formal bee kill report solicitation prompted the US EPA Pesticide Program Dialog Committee (PPDC) Crops and Pesticide- related Bee Kills (3) Economic Impacts and Bee-Kill Investigations (4) Additional ________________________________________________________________________________ Newsletter Subscriptions Bee-Kill Survey USDA APHIS Survey Canadian Nosema Studies

Ferrara, Katherine W.

492

ccsd-00002799,version1-7Sep2004 KILLING FORMS ON SYMMETRIC SPACES  

E-print Network

. Keywords: Killing forms, symmetric spaces. 1. Introduction There are two equivalent definitions of Killing vector fields on Riemannian manifolds. A vector field X is Killing if its local flow consists, ANDREI MOROIANU AND UWE SEMMELMANN Proposition 1.2. A symmetric space admitting real Killing spinors

Boyer, Edmond

493

KILLING SPINORS IN SUPERGRAVITY WITH 4-FLUXES ILKA AGRICOLA AND THOMAS FRIEDRICH  

E-print Network

KILLING SPINORS IN SUPERGRAVITY WITH 4-FLUXES ILKA AGRICOLA AND THOMAS FRIEDRICH Abstract. We study#12;ed geometrically. Contents 1. Introduction 1 2. Killing Spinors with 4-Fluxes on 3-Sasakian Manifolds 3 3. Killing Spinors with 4-Fluxes on Nearly Parallel G 2 -Manifolds 5 4. Killing Spinors with 4

Friedrich, Thomas

494

Nice guys finish last : A critical review of Killed in the Line of Duty  

Microsoft Academic Search

In 1992, the FBI published the report Killed in the Line of Duty: A Study of Selected Felonious Killings of Law Enforcement Officers. This study of 51 incidents in which law enforcement officers were killed, reported on the personality and characteristics of those who murder law enforcement officers, the types of officers who were killed and factors which contribute to

William R. King; Beth A. Sanders

1997-01-01

495

Modulation of Intestinal TLR4-Inflammatory Signaling Pathways by Probiotic Microorganisms: Lessons Learned from Lactobacillus jensenii TL2937  

PubMed Central

The intestinal mucosa plays a critical role in the host’s interactions with innocuous commensal microbiota and invading pathogenic microorganisms. Intestinal epithelial cells (IECs) and gut associated immune cells recognize the bacterial components via pattern-recognition receptors (PRRs) and are responsible for maintaining tolerance to the large communities of resident luminal bacteria while being also able to mount inflammatory responses against pathogens. Toll-like receptors (TLRs) are a major class of PRRs that are present on IECs and immune cells which are involved in the induction of both tolerance and inflammation. A growing body of experimental and clinical evidence supports the therapeutic and preventive application of probiotics for several gastrointestinal inflammatory disorders in which?TLRs exert a significant role. This review aims to summarize the current knowledge of the beneficial effects of probiotic microorganisms with the capacity to modulate the immune system (immunobiotics) in the regulation of intestinal inflammation in pigs, which are very important as both livestock and human model. Especially we discuss the role of?TLRs, their signaling pathways, and their negative regulators in both the inflammatory intestinal injury and the beneficial effects of immunobiotics in general, and Lactobacillus jensenii?TL2937 in particular. This review article emphasizes the cellular and molecular interactions of immunobiotics with IECs and immune cells through?TLRs and their application for improving animal and human health. PMID:24459463

Villena, Julio; Kitazawa, Haruki

2014-01-01

496

Modulation of Intestinal TLR4-Inflammatory Signaling Pathways by Probiotic Microorganisms: Lessons Learned from Lactobacillus jensenii TL2937.  

PubMed

The intestinal mucosa plays a critical role in the host's interactions with innocuous commensal microbiota and invading pathogenic microorganisms. Intestinal epithelial cells (IECs) and gut associated immune cells recognize the bacterial components via pattern-recognition receptors (PRRs) and are responsible for maintaining tolerance to the large communities of resident luminal bacteria while being also able to mount inflammatory responses against pathogens. Toll-like receptors (TLRs) are a major class of PRRs that are present on IECs and immune cells which are involved in the induction of both tolerance and inflammation. A growing body of experimental and clinical evidence supports the therapeutic and preventive application of probiotics for several gastrointestinal inflammatory disorders in which?TLRs exert a significant role. This review aims to summarize the current knowledge of the beneficial effects of probiotic microorganisms with the capacity to modulate the immune system (immunobiotics) in the regulation of intestinal inflammation in pigs, which are very important as both livestock and human model. Especially we discuss the role of?TLRs, their signaling pathways, and their negative regulators in both the inflammatory intestinal injury and the beneficial effects of immunobiotics in general, and Lactobacillus jensenii?TL2937 in particular. This review article emphasizes the cellular and molecular interactions of immunobiotics with IECs and immune cells through?TLRs and their application for improving animal and human health. PMID:24459463

Villena, Julio; Kitazawa, Haruki

2014-01-14

497

Stoichiometric Constraints Do Not Limit Successful Invaders: Zebra Mussels in Swedish Lakes  

PubMed Central

Background Elemental imbalances of carbon (C): nitrogen (N): phosphorus (P) ratios in food resources can constrain the growth of grazers owning to tight coupling between growth rate, RNA allocation and biomass P content in animals. Testing for stoichiometric constraints among invasive species is a novel challenge in invasion ecology to unravel how a successful invader tackles ecological barriers in novel ecosystems. Methodology/Principal Findings We examined the C?P and N?P ratios and the condition factor of a successful invader in lakes, the zebra mussel (Dreissena polymorpha), collected from two Swedish lakes. Concurrently, we analyzed the elemental composition of the food (seston) and tissue of the mussels in which nutrient composition of food and mussels varied over time. Zebra mussel condition factor was weakly related to the their own tissue N?P and C?P ratios, although the relation with the later ratio was not significant. Smaller mussels had relatively lower tissue N?P ratio and higher condition factor. There was no difference in C?P and N?P ratios between seston and mussels' tissues. Our results indicated that the variation in nutrient stoichiometry of zebra mussels can be explained by food quality and quantity. Conclusions/Significance Our study suggests that fitness of invasive zebra mussels is not constrained by nutrient stoichiometry which is likely to be important for their proliferation in novel ecosystems. The lack of imbalance in C?P and N?P ratios between seston and mussels along with high tissue C?P ratio of the mussel allow them to tolerate potential P limitation and maintain high growth rate. Moreover, zebra mussels are able to change their tissue C?P and N?P ratios in response to the variation in elemental composition of their food. This can also help them to bypass potential nutrient stoichiometric constraints. Our finding is an important step towards understanding the mechanisms contributing to the success of exotic species from stoichiometric principles. PMID:19401773

Naddafi, Rahmat; Eklöv, Peter; Pettersson, Kurt

2009-01-01

498

1 Biological Invaders syllabus, fall 2012 (draft 4/13/12) Description: An introduction to biological invasions including plants, animals, and microbes.  

E-print Network

and traits of invaded ecosystems. Role of humans in invasions, impacts of invasions on communities and ecosystems, management of invaded natural areas. Offered every fall term. Biological invasions are a leading hypotheses to explain what causes invasions. 4. Explain the effects of invasions on communities

Watson, Craig A.

499

Temporins A and B Stimulate Migration of HaCaT Keratinocytes and Kill Intracellular Staphylococcus aureus  

PubMed Central

The growing number of microbial pathogens resistant to available antibiotics is a serious threat to human life. Among them is the bacterium Staphylococcus aureus, which colonizes keratinocytes, the most abundant cell type in the epidermis. Its intracellular accumulation complicates treatments against resulting infections, mainly due to the limited diffusion of conventional drugs into the cells. Temporins A (Ta) and B (Tb) are short frog skin antimicrobial peptides (AMPs). Despite extensive studies regarding their antimicrobial activity, very little is known about their activity on infected cells or involvement in various immunomodulatory functions. Here we show that Tb kills both ATCC-derived and multidrug-resistant clinical isolates of S. aureus within infected HaCaT keratinocytes (80% and 40% bacterial mortality, respectively) at a nontoxic concentration, i.e., 16 ?M, whereas a weaker effect is displayed by Ta. Furthermore, the peptides prevent killing of keratinocytes by the invading bacteria. Further studies revealed that both temporins promote wound healing in a monolayer of HaCaT cells, with front speed migrations of 19 ?m/h and 12 ?m/h for Ta and Tb, respectively. Migration is inhibited by mitomycin C and involves the epidermal growth factor receptor (EGFR) signaling pathway. Finally, confocal fluorescence microscopy indicated that the peptides diffuse into the cells. By combining antibacterial and wound-healing activities, Ta and Tb may act as multifunctional mediators of innate immunity in humans. Particularly, their nonendogenous origin may reduce microbial resistance to them as well as the risk of autoimmune diseases in mammals. PMID:24514087

Di Grazia, Antonio; Luca, Vincenzo; Segev-Zarko, Li-av T.; Shai, Yechiel

2014-01-01

500

Temporins A and B stimulate migration of HaCaT keratinocytes and kill intracellular Staphylococcus aureus.  

PubMed

The growing number of microbial pathogens resistant to available antibiotics is a serious threat to human life. Among them is the bacterium Staphylococcus aureus, which colonizes keratinocytes, the most abundant cell type in the epidermis. Its intracellular accumulation complicates treatments against resulting infections, mainly due to the limited diffusion of conventional drugs into the cells. Temporins A (Ta) and B (Tb) are short frog skin antimicrobial peptides (AMPs). Despite extensive studies regarding their antimicrobial activity, very little is known about their activity on infected cells or involvement in various immunomodulatory functions. Here we show that Tb kills both ATCC-derived and multidrug-resistant clinical isolates of S. aureus within infected HaCaT keratinocytes (80% and 40% bacterial mortality, respectively) at a nontoxic concentration, i.e., 16 ?M, whereas a weaker effect is displayed by Ta. Furthermore, the peptides prevent killing of keratinocytes by the invading bacteria. Further studies revealed that both temporins promote wound healing in a monolayer of HaCaT cells, with front speed migrations of 19 ?m/h and 12 ?m/h for Ta and Tb, respectively. Migration is inhibited by mitomycin C and involves the epidermal growth factor receptor (EGFR) signaling pathway. Finally, confocal fluorescence microscopy indicated that the peptides diffuse into the cells. By combining antibacterial and wound-healing activities, Ta and Tb may act as multifunctional mediators of innate immunity in humans. Particularly, their nonendogenous origin may reduce microbial resistance to them as well as the risk of autoimmune diseases in mammals. PMID:24514087

Di Grazia, Antonio; Luca, Vincenzo; Segev-Zarko, Li-Av T; Shai, Yechiel; Mangoni, Maria Luisa

2014-05-01