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1

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

2

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

3

Study on the killing of oceanic harmful micro-organisms in ship's ballast water using oxygen active particles  

NASA Astrophysics Data System (ADS)

Global Environment Facility has identified that the spread of marine invasive alien species is one of the four major risk factors threatening the safety of global marine environments. Ballast water discharge is the main cause of biological invasion. With physical methods of strong electric field ionization discharge at atmospheric pressure, O2 and sea water (gaseous) were ionized, and then dissociated to a number of oxygen active particles (ROS) such as ·OH, O2+, H2O+, etc. ROS was injected into 0.6 t h-1 ballast water treatment system to form high concentration ROS solution in order to kill the harmful micro-organisms in ballast water. According to the land-based test standard of International Maritime Organization (IMO) Guidelines for Approval of Ballast Water Management Systems (G8), this paper concludes that single-cell algae of 3.0 × 104 cell ml-1 and bacteria of 2.0 × 104 cfu ml-1 were killed by ROS solution of 2.0 ppm. Death rate could reach almost 100%. The results meet the requirements of Regulation D-2 of International Convention for the Control and Management of Ships' Ballast Water and Sediments completely.

Chen, C.; Meng, X. Y.; Bai, M. D.; Tian, Y. P.; Jing, Y.

2013-03-01

4

INVADERS Database  

NSDL National Science Digital Library

Based at the University of Montana and directed by Dr. Peter Rice, the INVADERS Database is "a comprehensive database of exotic plant names and weed distribution records for five states in the northwestern United States." Designed for use by land management and weed regulatory agencies, INVADERS uses a query interface (plant name or location) to sort and display information. Data are updated regularly so as to increase the chance of detecting and halting the rapid spread of alien weeds. Highlights of the site include the noxious weed listings for all US states and six Canadian provinces, historic distribution records against which to compare current plant distributions, and summary statistics such as the number of invasive species detected per state or a summary of the 120 year invasion, among others. The INVADERS database will prove both interesting and useful to managers and academics, alike.

5

Silent Invaders  

NSDL National Science Digital Library

Silent Invaders introduces the problem of invasive species and provides information on control activities. The videos explain how invasive species get into the United States, why some do so well here, and how we can keep invasive species out. There is an interactive section where the user tries to eliminate musk thistle by applying a combination of biological, fire, chemical and mechanical controls. Other featured species include cheatgrass, tamarisk, woolly adelgid, zebra mussel, and fire ants. The field guide contains a list of invasive plant and animal species as well as photographs and movies. The instructor guide is a weed science primer for teachers.

Lahart, David

6

Mechanism of Action of the Antimicrobial Peptide Buforin II: Buforin II Kills Microorganisms by Penetrating the Cell Membrane and Inhibiting Cellular Functions  

Microsoft Academic Search

The mechanism of action of buforin II, which is a 21-amino acid peptide with a potent antimicrobial activity against a broad range of microorganisms, was studied using fluorescein isothiocyanate (FITC)-labeled buforin II and a gel-retardation experiment. Its mechanism of action was compared with that of the well-characterized magainin 2, which has a pore-forming activity on the cell membrane. Buforin II

Chan Bae Park; Hun Sik Kim; Sun Chang Kim

1998-01-01

7

Nab the Aquatic Invader!  

NSDL National Science Digital Library

In this activity, younger students assume the roles of detectives investigating the ten "most wanted" invasive species. They examine background information on these species and learn about how they came to be invaders, how they spread, some environmental and economic impacts, and some solutions for controlling them. When they think they have enough information to "book" an invasive species, they click on the "Book 'em" file and answer questions about each one.

8

Myeloperoxidase: a front-line defender against phagocytosed microorganisms  

PubMed Central

Successful immune defense requires integration of multiple effector systems to match the diverse virulence properties that members of the microbial world might express as they initiate and promote infection. Human neutrophils—the first cellular responders to invading microbes—exert most of their antimicrobial activity in phagosomes, specialized membrane-bound intracellular compartments formed by ingestion of microorganisms. The toxins generated de novo by the phagocyte NADPH oxidase and delivered by fusion of neutrophil granules with nascent phagosomes create conditions that kill and degrade ingested microbes. Antimicrobial activity reflects multiple and complex synergies among the phagosomal contents, and optimal action relies on oxidants generated in the presence of MPO. The absence of life-threatening infectious complications in individuals with MPO deficiency is frequently offered as evidence that the MPO oxidant system is ancillary rather than essential for neutrophil-mediated antimicrobial activity. However, that argument fails to consider observations from humans and KO mice that demonstrate that microbial killing by MPO-deficient cells is less efficient than that of normal neutrophils. We present evidence in support of MPO as a major arm of oxidative killing by neutrophils and propose that the essential contribution of MPO to normal innate host defense is manifest only when exposure to pathogens overwhelms the capacity of other host defense mechanisms. PMID:23066164

Klebanoff, Seymour J.; Kettle, Anthony J.; Rosen, Henry; Winterbourn, Christine C.; Nauseef, William M.

2013-01-01

9

Insect Invaders Capture Headlines  

NSDL National Science Digital Library

Lately, a few insects not native to the North American continent have made headlines while making themselves at home. According to a recent study from the journal Science, a European fruit fly species, Drosophila subobscura, has replaced close to 95 percent of native North and South American fruit flies in the 20 years it has been in these climes. Even more striking is the fact that the non-native flies have evolved in the process. Over the last 10,000 years, European D. subobscura flies that lived in higher latitudes produced individuals with wing sizes that were four percent larger than their lower latitude counterparts. Strangely, in North America, it has taken less than two decades for the higher latitude fruit fly to grow to be four percent larger than those living south. In essence, the fruit fly population has transformed itself almost as fast as it has taken over its new environment. The findings point scientists to new questions regarding both the rapid evolution of an invader along with the ecological consequences of its arrival. Another recent report, from Reuters, describes the Asian long-horned beetle's devastation of trees in New York and Chicago. The beetle has been called the worst non-native pest since the gypsy moth, and the government is searching for solutions to this menace which bores holes into trees and damages their vascular systems. This week's In the News takes a closer look at these adaptable invaders and the problems of invasive species in general.

Ramanujan, Krishna.

10

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

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

Progress in invasion biology: predicting invaders  

Microsoft Academic Search

Predicting which species are probable invaders has been a long-standing goal of ecologists, but only recently have quantitative methods been used to achieve such a goal. Although restricted to few taxa, these studies reveal clear relationships between the characteristics of releases and the species involved, and the successful establishment and spread of invaders. For example, the probability of bird establishment

Cynthia S. Kolar; David M. Lodge

2001-01-01

13

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.

14

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

15

PERSPECTIVE Anthropogenically induced adaptation to invade (AIAI)  

E-print Network

PERSPECTIVE Anthropogenically induced adaptation to invade (AIAI): contemporary adaptation to human of evolution in invasions, particu- larly rapid adaptive evolution during invasions, has recently become remote) new loca- tion, rather than a focus on evolution within the native Keywords adaptation

Hufbauer, Ruth A.

16

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

17

The Jeremiah Metzger Lecture. Microbial defenses against killing by phagocytes.  

PubMed Central

Phagocytes are a key feature of defense against microorganisms. Phagocyte function is a complex system with many intricately involved components. Each of these components provides microorganisms with a target for countermeasures against phagocytes. We have discussed examples and purported mechanisms for microbial defenses against the steps involved in killing by phagocytes. Understanding the interplay of these host and pathogen factors leads to a better understanding of both normal host defenses and pathogenesis of disease. PMID:1413380

Mandell, G. L.; Frank, M. O.

1992-01-01

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

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

20

Cercopagis Pengoi Invades the Great Lakes  

NSDL National Science Digital Library

The Environmental Protection Agency (EPA)'s Great Lakes National Program Office provides this research information page on the recent invasion of the exotic crustacean, Cercopagis pengoi, into the Great Lakes. Cercopagis, a predatory cladoceran, is similar to Bythotrephes cederstroemi, another recent Great Lakes invader; both species occur in freshwater and brackish environments. The site provides background information, images (including figures showing distribution and abundance), links, and selected references regarding this exotic species.

Barbiero, Rick.; Dimartino, Mark.; Kuhns, Linda.

1998-01-01

21

Ecology. Plant invader may use chemical weapons.  

PubMed

On page 521, plant ecologists offer a novel explanation for the success of invasive plants. By comparing how one species of knapweed, Centaurea diffusa, behaves with its natural neighbors and with foreign plant species that evolved separately, they found that the invader apparently gains an edges in its adopted home not only by ditching its herbivores but by wielding weaponry: chemicals exuded from its roots that hamper its new neighbors' growth. PMID:11183749

Jensen, M N

2000-10-20

22

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

Code of Federal Regulations, 2010 CFR

... false Newtown Creek, Dutch Kills, English Kills and their tributaries. 117...801 Newtown Creek, Dutch Kills, English Kills and their tributaries. (a...bridges across Newtown Creek, Dutch Kills, English Kills, and their tributaries:...

2010-07-01

23

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

24

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

25

Wanted Dead, Not Alive: Invading Species  

NSDL National Science Digital Library

The Why Files (last mentioned in the June 28, 2002 NSDL Scout Report for the Life Sciences) is "a popular and critically acclaimed web site that explores the science behind the news." Check out this recent feature of the Web site, which presents information about a number of harmful invasive species in an entertaining way. The notorious snakehead fish is included in the species lineup, and the related text helps to clear up misconceptions some may have about this invader. While some species and the problems associated with them are described in more detail than others, nearly all descriptions include links to related Web sites that offer much more detailed information.

2002-01-01

26

Killing tensors and canonical geometry  

NASA Astrophysics Data System (ADS)

The systematic derivation of constants of the motion, based on Killing tensors and the gauge covariant approach, is outlined. Quantum dots are shown to support second-, third- and fourth-rank Killing tensors.

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

2014-06-01

27

Age Invaders: Entertainment for Elderly and Young  

NASA Astrophysics Data System (ADS)

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

Cheok, Adrian David

28

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.

Erica F. Kosal

2003-01-01

29

Poverty and Witch Killing  

Microsoft Academic Search

This study uses rainfall variation to estimate the impact of income shocks on murder in rural Tanzania. Extreme rainfall (drought or flood) leads to a large increase in the murder of „witches”—typically elderly women killed by relatives—but not other murders. The findings provide novel evidence on the role of income shocks in causing violent crime, and religious violence in particular.

Edward Miguel

2005-01-01

30

Pathogenic Microorganisms in Water  

NSDL National Science Digital Library

Pathogenic Microorganisms in Water: Traditionally, groundwater has been used without treatment because the soil acts as a filter, removing pathogenic microorganisms. Some potential sources of pathogens (or disease causing organisms) in groundwater include septic tanks, leaking sewer lines, sewage sludge, intentional groundwater recharge with sewage, irrigation with sewage, direct injection of sewage, domestic solid waste disposal (landfills) and sewage oxidation ponds. The objective of the session is to introduce hydrogeologist to the types of microorganisms, sources of pathogens, and a simple exercise that can be incorporated into a hydrogeology class.

Melissa Lenczewski

31

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

32

Micro-organ device  

NASA Technical Reports Server (NTRS)

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

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

2013-01-01

33

Charged conformal Killing spinors  

NASA Astrophysics Data System (ADS)

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

Lischewski, Andree

2015-01-01

34

Killing Horizons and Spinors  

E-print Network

We study the near horizon geometry of generic Killing horizons constructing suitable coordinates and taking the appropriate scaling limit. We are able to show that the geometry will always show an enhancement of symmetries, and, in the extremal case, will develop a causally disconnected "throat" as expected. We analyze the implications of this to the Kerr/CFT conjecture and the attractor mechanism. We are also able to construct a set of special (pure) spinors associated with the horizon structure using their interpretation as maximally isotropic planes. The structure generalizes the usual reduced holonomy manifold in an interesting way and may be fruitful to the search of new types of compactification backgrounds.

Bruno Carneiro da Cunha; Amilcar de Queiroz

2014-06-19

35

Donor and recipient regions: The biogeography of macrobenthic invaders  

EPA Science Inventory

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

36

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

37

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

38

Micro-Organ Devices  

NASA Technical Reports Server (NTRS)

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

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

2009-01-01

39

Brucella melitensis invades murine erythrocytes during infection.  

PubMed

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

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

2014-09-01

40

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.

Nancy P. Moreno

2008-01-01

41

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

42

Invader immunology: invasion history alters immune system function in cane toads (Rhinella marina) in tropical Australia.  

PubMed

Because an individual's investment into the immune system may modify its dispersal rate, immune function may evolve rapidly in an invader. We collected cane toads (Rhinella marina) from sites spanning their 75-year invasion history in Australia, bred them, and raised their progeny in standard conditions. Evolved shifts in immune function should manifest as differences in immune responses among the progeny of parents collected in different locations. Parental location did not affect the offspring's cell-mediated immune response or stress response, but blood from the offspring of invasion-front toads had more neutrophils, and was more effective at phagocytosis and killing bacteria. These latter measures of immune function are negatively correlated with rate of dispersal in free-ranging toads. Our results suggest that the invasion of tropical Australia by cane toads has resulted in rapid genetically based compensatory shifts in the aspects of immune responses that are most compromised by the rigours of long-distance dispersal. PMID:25399668

Brown, Gregory P; Phillips, Benjamin L; Dubey, Sylvain; Shine, Richard

2015-01-01

43

Two Different Rickettsial Bacteria Invading Volvox carteri  

PubMed Central

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

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

2015-01-01

44

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

NASA Technical Reports Server (NTRS)

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

Smithers, G. A.

1992-01-01

45

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

46

Leaf Litter Disappearance in Earthworm-Invaded Northern  

E-print Network

Leaf Litter Disappearance in Earthworm-Invaded Northern Hardwood Forests: Role of Tree Species, Penrith, NSW 2751, Australia ABSTRACT Earthworm invasion in North American temperate forest reduces forest floor mass, yet the interactions between litter composition, invasive earthworm community composition

Minnesota, University of

47

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

48

Detecting the presence of microorganisms  

NASA Technical Reports Server (NTRS)

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

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

1977-01-01

49

Inactivation of Microorganisms  

Microsoft Academic Search

\\u000a Minimal processing techniques for food preservation allow better retention of product flavor, texture, color, and nutrient\\u000a content than comparable conventional treatments. A wide range of novel alternative physical factors have been intensely investigated\\u000a in the last two decades. These physical factors can cause inactivation of microorganisms at ambient or sublethal temperatures\\u000a (e.g., high hydrostatic pressure, pulsed electric fields, ultrasound, pulsed

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

2011-01-01

50

Male-killing bacterium in a fifth ladybird beetle, Coleomegilla maculata (Coleoptera: Coccinellidae)  

Microsoft Academic Search

Inherited symbionts which selectively cause the death of male hosts are found widely across the Insecta. Previous studies have shown a single, but different micro-organism to be responsible for male-killing in each taxonomic group studied. We here produce evidence that within a group of insects, the Coccinellidae, there is more than one causal agent of male lethality. We report a

Gregory D D Hurst; Tansy C Hammarton; John J Obrycki; Tamsin M O Majerus; Linda E Walker; Dominique Bertrand; Michael E N Majerus; Gregory DD Hurst

1996-01-01

51

Microorganisms for producing organic acids  

SciTech Connect

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

Pfleger, Brian Frederick; Begemann, Matthew Brett

2014-09-30

52

[Bioterrorism and pathogenic microorganisms].  

PubMed

In recent years the use of pathogenic microorganisms in acts of bioterrorism has been the subject of major concern in many countries. This paper presents a possible application of viruses and bacteria for warfare and terrorist purposes, as well as a laboratory diagnosis to identify those agents. The viruses of smallpox (orthopoxvirus), of hemorrhagic fever and those belonging to filovirus have been highlighted, inter alia, as agents of human infection with bioterrorist intent. Among the bacteria, the emphasis has been on anthrax (Bacillus anthracis), the plague (Yersinia pestis), botulism (Clostridium botulinum) and tularemia (Francisella tularensis), not to mention ricin (Ricinus communis), as one of the Group B agents. PMID:24473660

Schatzmayr, Hermann G; Barth, Ortrud Monika

2013-10-01

53

The race of microorganisms  

NSDL National Science Digital Library

This reading, part of a site devoted to the science of cooking, explores how beneficial bacteria are involved in the fermentation process that is used to pickle vegetables. The reading focuses on the competition between those microorganisms that facilitate fermentation and those microbes that damage this food production process. Lactic acid bacteria are key players in the creation of pickles. The reading explains the functions of these bacteria and describes the conditions in a pickle crock--including the appropriate salt concentration, a lack of oxygen, and optimal temperature--that allow them to thrive. A sidebar points out how pickles become crunchy through osmosis. Copyright 2005 Eisenhower National Clearinghouse

Exploratorium

2004-01-01

54

Biofilms: survival mechanisms of clinically relevant microorganisms.  

PubMed

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

Donlan, Rodney M; Costerton, J William

2002-04-01

55

Biofilms: Survival Mechanisms of Clinically Relevant Microorganisms  

PubMed Central

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

Donlan, Rodney M.; Costerton, J. William

2002-01-01

56

Gravitaxis in unicellular microorganisms  

NASA Astrophysics Data System (ADS)

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

Häder, D.-P.

1999-01-01

57

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

58

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

59

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

60

Furtive foes: algal viruses as potential invaders Janice E. Lawrence  

E-print Network

Furtive foes: algal viruses as potential invaders Janice E. Lawrence Lawrence, J. E. 2008. Furtive, marine viruses. Received 26 June 2007; accepted 26 January 2008. J. E. Lawrence: Biology Department in phytoplankton population dynamics, Lampert and Sommer (1997) provided the equation l ¼ g þ s þ x þ d þ p þ v

Lawrence, J.E.

61

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

NASA Technical Reports Server (NTRS)

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

Stan-Lotter, Helga; Denner, Ewald

1993-01-01

62

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

NASA Technical Reports Server (NTRS)

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

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

1993-01-01

63

[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

64

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

65

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

66

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

E-print Network

Streptococcus pneumoniae Invades Erythrocytes and Utilizes Them to Evade Human Innate Immunity Hospital for Infection Control, Nagoya University Hospital, Nagoya, Aichi, Japan Abstract Streptococcus. (2013) Streptococcus pneumoniae Invades Erythrocytes and Utilizes Them to Evade Human Innate Immunity

Nizet, Victor

67

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

68

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

69

Laser Microbial Killing and Biofilm Disruption  

NASA Astrophysics Data System (ADS)

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

Krespi, Yosef P.; Kizhner, Victor

2009-06-01

70

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

71

Access Invaders: Developing a Universally Accessible Action Game  

Microsoft Academic Search

This paper depicts the notion of Universally Accessible Games and presents the development of a related action game entitled\\u000a Access Invaders. The design of the game’s user interface which accommodates concurrently the needs of people with diverse\\u000a abilities is described, along with the approach followed to adapt the game logic and content to achieve accessibility. In\\u000a this context, the concept

Dimitris Grammenos; Anthony Savidis; Yannis Georgalis; Constantine Stephanidis

2006-01-01

72

Land-use change in a tropical mountain rainforest region of southern Ecuador affects soil microorganisms and nutrient cycling  

Microsoft Academic Search

Over the past decades, the tropical mountain rainforest of southern Ecuador has been threatened by conversion to cattle pastures.\\u000a Frequently, these pastures are invaded by bracken fern and abandoned when bracken becomes dominant. Changes in land-use (forest–pasture–abandoned\\u000a pasture) can affect soil microorganisms and their physiological responses with respect to soil carbon and nutrient cycling.\\u000a In situ investigations on litter decomposition

Karin Potthast; Ute Hamer; Franz Makeschin

73

9 CFR 113.209 - Rabies Vaccine, Killed Virus.  

Code of Federal Regulations, 2010 CFR

... 1 2010-01-01 2010-01-01 false Rabies Vaccine, Killed Virus. 113.209 Section...REQUIREMENTS Killed Virus Vaccines § 113.209 Rabies Vaccine, Killed Virus. Rabies Vaccine (Killed Virus) shall be prepared...

2010-01-01

74

Shock compression and recovery of microorganism-loaded broths and an emulsion  

NASA Astrophysics Data System (ADS)

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

Hazell, Paul; Beveridge, Cliff; Groves, Kathy

2009-06-01

75

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

NASA Astrophysics Data System (ADS)

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

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

2009-12-01

76

Desert Dust Kills Florida Fish  

NSDL National Science Digital Library

This National Aeronautics and Space Administration (NASA) article discusses the connection between dust storms in Africa, and red tides along the Florida coast. Red tides are blooms of toxic algae that kill fish, birds, and mammals, as well as cause health problems in humans. Storm activity in the Sahara Desert region kicks up topsoil that winds transport into the Gulf of Mexico. These clouds fertilize the water with iron, which bacteria named Trichodesmium use to create nitrogen. The nitrogen makes the water a friendly environment for the toxic algae. This article discusses this process and research that is going on to help solve the problem. Audio version is available as well.

77

Integrability conditions for Killing-Yano tensors and conformal Killing-Yano tensors  

NASA Astrophysics Data System (ADS)

The integrability conditions for the existence of a conformal Killing-Yano tensor of arbitrary order are worked out in all dimensions and expressed in terms of the Weyl tensor. As a consequence, the integrability conditions for the existence of a Killing-Yano tensor are also obtained. By means of such conditions, it is shown that in certain Einstein spaces one can use a conformal Killing-Yano tensor of order p to generate a Killing-Yano tensor of order (p -1 ) . Finally, it is proved that in maximally symmetric spaces the covariant derivative of a Killing-Yano tensor is a closed conformal Killing-Yano tensor and that every conformal Killing-Yano tensor is uniquely decomposed as the sum of a Killing-Yano tensor and a closed conformal Killing-Yano tensor.

Batista, Carlos

2015-01-01

78

Letting die and mercy killing.  

PubMed

We are all called to make moral decisions, not only about preserving life and health, but also about accepting our death and dying. There are situations, when it is morally right, and indeed obligatory, to allow a dying person to die in peace and dignity. But there is a world of difference between allowing a peaceful death, and deliberately setting out to bring death of the person either by acts of commission (s.c. 'active euthanasia'), or by acts of omission (s.c. 'passive euthanasia'). The word "killing" seems proper for euthanasia, because "to kill" does mean " to intentionally cause the death of someone." It can be morally acceptable to withhold or withdraw a treatment precisely because it is reasonably judged as inefficacious (futile), or excessively burdensome for the patient. One's reason for withholding such treatment must not be a judgement about the desirability of putting an end to the patient's life, but a judgement about the desirability of putting an end to the treatment, which is futile or burdensome. PMID:16294443

Narbekovas, Andrius; Meilius, Kazimieras

2003-01-01

79

Novel drugs from marine microorganisms.  

PubMed

Marine microorganisms have expected mounting consideration on the basis of bioactive metabolites and propose an exclusive prospect to both enhance the amount of aquatic natural foodstuffs in clinical trials as well as speed up their progress. This review focuses particularly on those molecules, originated from marine microorganisms, presently in the medical pipeline that have been recognized or highly expected to be identified based on growing incidental evidence. Particularly karlotoxin class compounds, isolated from dinoflagellate Karlodinium veneficum, offer chances to create new molecules for control of cancer and high serum cholesterol levels. PMID:21599497

Javed, Faraza; Qadir, M Imran; Janbaz, Khalid Hussain; Ali, Muhammad

2011-08-01

80

Quantitative aspects of the interactive killing effects between X rays and other mutagens in microorganisms  

Microsoft Academic Search

Recently we presented a mathematical description of the synergistic interaction which occurs when Escherichia coli B\\/r is exposed to both X rays and 254 nm ultraviolet light. Here we extend this approach to other bacteria and describe a graphical technique which can be used to determine the nature and relative importance of second and third degree terms in the function

D. D. Ager; R. H. Haynes

1988-01-01

81

Quantitative aspects of the interactive killing effects between X rays and other mutagens in microorganisms  

SciTech Connect

Recently we presented a mathematical description of the synergistic interaction which occurs when Escherichia coli B/r is exposed to both X rays and 254 nm ultraviolet light. Here we extend this approach to other bacteria and describe a graphical technique which can be used to determine the nature and relative importance of second and third degree terms in the function h(x, y), which describes the dose dependence of such effects. In most cases, interaction functions appear to be dominated, in the biologically interesting dose range, by a second degree term in the product, xy, of the doses of the two agents. We find that the magnitudes of these interactions vary among the organisms examined and can be surprisingly large. Finally, we show that the simple xy dependence observed for most interactions does not carry any unambiguous implications with respect to previous speculations on the mechanisms of these effects.

Ager, D.D.; Haynes, R.H.

1988-07-01

82

A kill curve for Phanerozoic marine species  

NASA Technical Reports Server (NTRS)

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

Raup, D. M.

1991-01-01

83

Smaller Fleas: Viruses of Microorganisms  

PubMed Central

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

Hyman, Paul; Abedon, Stephen T.

2012-01-01

84

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...

85

Pseudomonas aeruginosa invades corneal epithelial cells during experimental infection.  

PubMed Central

Pseudomonas aeruginosa is considered an extracellular pathogen. Using assays to determine intracellular survival in the presence of gentamicin, we have demonstrated that some strains of P. aeruginosa are able to invade corneal cells during experimental bacterial keratitis in mice. Although intracellular bacteria were detectable 15 min after inoculation, the number of intracellular bacteria increased in a time-dependent manner over a 24-h period. Levels of invasion were similar when bacteria were grown as a biofilm on solid medium and when they were grown in suspension. Intracellular bacteria survived in vitro for at least 24 h, although only minimal bacterial multiplication within cells was observed. P. aeruginosa PAK and Escherichia coli HB101 did not cause disease in this model and were not isolated from corneas after 24 h even when an inoculum of 10(8) CFU was applied. Transmission electron microscopy of corneal epithelium from eyes infected for 8 h revealed that intracellular bacteria were present within membrane-bound vacuoles, which suggests that bacterial entry was an endocytic process. At 24 h, the observation of many bacteria free in the cytoplasm indicated that P. aeruginosa was able to escape the endocytic vacuole. The ability of some P. aeruginosa strains to invade corneal epithelial cells may contribute to the pathogenesis or to the progression of disease, since intracellular bacteria can evade host immune effectors and antibiotics commonly used to treat infection. Images PMID:8039920

Fleiszig, S M; Zaidi, T S; Fletcher, E L; Preston, M J; Pier, G B

1994-01-01

86

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

87

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Coast Guard 33 CFR Part 117 [Docket No. USCG-2010-0355] Drawbridge Operation Regulations; Newtown Creek, Dutch Kills, English Kills, and Their Tributaries, NY, Maintenance AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from...

2010-06-01

88

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Coast Guard 33 CFR Part 117 [Docket No. USCG-2010-0907] Drawbridge Operation Regulations; Newtown Creek, Dutch Kills, English Kills, and Their Tributaries, NY, Maintenance AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from...

2010-10-12

89

Pulpability of Beetle-Killed Spruce  

E-print Network

Pulpability of Beetle-Killed Spruce United States Department of Agriculture Forest Service Forest the value of beetle-killed spruce as pulpwood. The results showed that live and dead spruce wood can quality. Log deterioration had mixed effects on paper properties. Keywords: pulp, spruce, sap rot

Abubakr, Said

90

Hypersurface homogeneous Killing spinor space-times  

NASA Astrophysics Data System (ADS)

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.

Van den Bergh, N.

2015-01-01

91

Children killed by genetic parents versus stepparents  

Microsoft Academic Search

Despite many empirical studies of children killed by parents, there has been little theoretical progress. An examination of 378 cases in a national register revealed that circumstances differed for genetic parents versus stepparents. Infants were at greatest risk of filicide, especially by genetic mothers. Genetic mothers who killed offspring, especially older children, disproportionately had a mental illness and received relatively

Grant T. Harris; N. Zoe Hilton; Marnie E. Rice; Angela W. Eke

2007-01-01

92

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

Microsoft Academic Search

Predicting exotic invaders and reducing their impacts on the biodiversity and function of native ecosystems require understanding\\u000a of the mechanisms that facilitate their success during key stages of invasion. We determined whether clonal growth, characteristic\\u000a of the majority of successful invaders of natural areas, facilitates the proliferation of Bromus inermis (smooth brome), an exotic grass invading prairie ecosystems across the

R. Otfinowski; N. C. Kenkel

2008-01-01

93

Autophagy Defends Cells Against Invading Group A Streptococcus  

Microsoft Academic Search

We found that the autophagic machinery could effectively eliminate pathogenic group A Streptococcus (GAS) within nonphagocytic cells. After escaping from endosomes into the cytoplasm, GAS became enveloped by autophagosome-like compartments and were killed upon fusion of these compartments with lysosomes. In autophagy-deficient Atg5-\\/- cells, GAS survived, multiplied, and were released from the cells. Thus, the autophagic machinery can act as

Ichiro Nakagawa; Atsuo Amano; Noboru Mizushima; Akitsugu Yamamoto; Hitomi Yamaguchi; Takahiro Kamimoto; Atsuki Nara; Junko Funao; Masanobu Nakata; Kayoko Tsuda; Shigeyuki Hamada; Tamotsu Yoshimori

2004-01-01

94

Intergenomic arms races: detection of a nuclear rescue gene of male-killing in a ladybird.  

PubMed

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 gamma-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; Majerus, Michael E N

2010-01-01

95

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

96

Mount Unzen kills three volcanologists  

NASA Astrophysics Data System (ADS)

Three AGU members were among 37 people killed June 3 when Mount Unzen, a volcano in Nagasaki prefecture, Japan, erupted. Unzen last erupted in 1792. The first signs of renewed activity appeared in mid-1990, with increases in seismicity and the first volcanic tremor since observations began in 1966. The three volcanologists, Harry Glicken and Maurice and Katia Krafft, had traveled to Mount Unzen to monitor the increased seismic activity. Glicken, 33, was a visiting scientist at Tokyo Metropolitan University and an assistant researcher in geological sciences at the University of California, Santa Barbara. He worked for the U.S. Geological Survey until 1989, and narrowly escaped death in the 1980 eruption of Mount St. Helens in Washington.Glicken had been an AGU member since 1980 and was known for his work in debris avalanches. Maurice, 45, and Katia Krafft, 44, of Cernay, France, were professional volcanologists known for their extensive work in publishing books and films on volcanology for the general public. Both Kraffts joined AGU in 1975.

DeVito, M. Catherine

97

ALLELOPATHIC GROWTH STIMULATION OF PLANTS AND MICROORGANISMS.  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

98

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

99

4, 26672697, 2007 Micro-organisms in  

E-print Network

BGD 4, 2667­2697, 2007 Micro-organisms in the South-East Pacific S. Masquelier and D. Vaulot Title Distribution of micro-organisms along a transect in the South-East Pacific Ocean (BIOSOPE cruise) from, 2667­2697, 2007 Micro-organisms in the South-East Pacific S. Masquelier and D. Vaulot Title Page

Paris-Sud XI, Université de

100

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

101

Phylogenetic relationships among subsurface microorganisms  

SciTech Connect

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

Nierzwicki-Bauer, S.A.

1991-01-01

102

Microorganisms  

NSDL National Science Digital Library

Learn About Microbes Name three places where microbes live. Meet the Microbes Select the word infection at the top of the Meet the Microbe page. Meet the Microbes Go into at least three different areas and do the activity. In your notebook record where you went, what you did and write down at least three things you ...

Ms. Kirby

2009-09-16

103

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

PubMed Central

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

2014-01-01

104

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

105

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...

106

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

107

Predicting the identity and impact of future biological invaders: a priority for aquatic resource management  

Microsoft Academic Search

The identification and risk assessment of potential biological invaders would provide valuable criteria for the allocation of resources toward the detection and control of invasion threats. Yet, freshwater biologists have made few attempts at predicting potential invaders, apparently because such efforts are perceived to be costly and futile. We describe some simple, low-cost empirical approaches that would facilitate prediction and

Anthony Ricciardi; Joseph B. Rasmussen

1998-01-01

108

Pemberton et al: ALIEN TERRESTRIAL ORCHID, EULOPHIA GRAMINEA, INVADES MIAMI ALIEN TERRESTRIAL ORCHID, EULOPHIA GRAMINEA,  

E-print Network

Pemberton et al: ALIEN TERRESTRIAL ORCHID, EULOPHIA GRAMINEA, INVADES MIAMI 183 ALIEN TERRESTRIAL ORCHID, EULOPHIA GRAMINEA, INVADES MIAMI Bob Pemberton, PhD, Suzanne Koptur, PhD & Timothy Collins, PhD We first encountered an Asian orchid, Eulophia graminea, in South Miami during the autumn of 2007

Koptur, Suzanne

109

Alternative Mechanism of Eimeria bovis Sporozoites to Invade Cells In Vitro by Breaching the Plasma Membrane  

Microsoft Academic Search

In vitro Eimeria bovis sporozoites invade a wide range of cell types, and in the case of bovine cells, they may develop to first- generation schizonts. Often, however, they subsequently leave their host cell to invade a new one, which seems contrary to the classical way of infecting a cell by forming a parasitophorous vacuole. Using a standard, ''cell wound

J. H. Behrendt; W. Clauss; H. Zahner; C. Hermosilla

2004-01-01

110

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

111

33 CFR 117.702 - Arthur Kill.  

Code of Federal Regulations, 2010 CFR

...REGULATIONS Specific Requirements New Jersey § 117.702 Arthur Kill...predicted high tide taken at the Battery, New York. (e) The bridge operator...the Coast Guard Captain of the Port New York. The bridge...

2010-07-01

112

33 CFR 117.702 - Arthur Kill.  

Code of Federal Regulations, 2012 CFR

...REGULATIONS Specific Requirements New Jersey § 117.702 Arthur Kill...predicted high tide taken at the Battery, New York. (e) The bridge operator...the Coast Guard Captain of the Port New York. The bridge...

2012-07-01

113

33 CFR 117.702 - Arthur Kill.  

Code of Federal Regulations, 2011 CFR

...REGULATIONS Specific Requirements New Jersey § 117.702 Arthur Kill...predicted high tide taken at the Battery, New York. (e) The bridge operator...the Coast Guard Captain of the Port New York. The bridge...

2011-07-01

114

33 CFR 117.702 - Arthur Kill.  

Code of Federal Regulations, 2014 CFR

...REGULATIONS Specific Requirements New Jersey § 117.702 Arthur Kill...predicted high tide taken at the Battery, New York. (e) The bridge operator...the Coast Guard Captain of the Port New York. The bridge...

2014-07-01

115

33 CFR 117.702 - Arthur Kill.  

Code of Federal Regulations, 2013 CFR

...REGULATIONS Specific Requirements New Jersey § 117.702 Arthur Kill...predicted high tide taken at the Battery, New York. (e) The bridge operator...the Coast Guard Captain of the Port New York. The bridge...

2013-07-01

116

On the swimming of microorganisms  

NASA Astrophysics Data System (ADS)

Strategies for swimming adopted by microorganisms must conform to the physical principles of self-propulsion at low Reynolds numbers. Here we present an analysis that directly relates the translational and rotational speeds to the surface motions of a swimming object and, for swimming spheres, makes evident novel constraints on potential mechanisms for propulsion. The results are then used to consider strategies for the swimming of a cyanobacterium, an organism whose motile mechanism is unknown, by considering incompressible streaming of the cell surface and oscillatory, tangential surface deformations. Finally, the efficiency of swimming using tangential motions is related directly to the surface velocities and a bound on the efficiency is obtained.

Samuel, Aravi D. T.; Stone, Howard A.

1996-11-01

117

Tailored synthesis of amine N-halamine copolymerized polystyrene with capability of killing bacteria.  

PubMed

Novel amine N-halamine copolymerized polystyrene (ANHCPS) nanostructures were controllably fabricated as potent antibiotics by using the surfactant-free emulsion copolymerization for killing pathogenic bacteria. The morphology and size of the ANHCPS were well tailored by tuning reaction conditions such as monomer molar ratio, temperature, and copolymerization time. Effect of chlorination aging time on the oxidative chlorine content in the ANHCPS was established, and the oxidative chlorine content was determined by the modified iodometric/thiosulfate technique. Antibacterial behavior of the ANHCPS on bacterial strain was evaluated using Staphylococcusaureus and Escherichiacoli as model pathogenic bacteria via the plate counting technique, inhibition zone study, and time-kill assay. Antimicrobial results illustrated that the ANHCPS possessed superior antibacterial capability of killing pathogenic bacteria. The destruction induced by the ANHCPS on bacterial surface structure was proven by using SEM technique. The effect of the oxidative chlorine content and morphology/size on the antimicrobial capability was constructed as well. This study provides us a novel approach for controllably synthesizing amine N-halamine polymers, and making them the potent candidates for killing bacteria or even the control of microorganism contamination. PMID:25585280

Cai, Qian; Bao, Sarina; Zhao, Yue; Zhao, Tianyi; Xiao, Linghan; Gao, Ge; Chokto, Harnoode; Dong, Alideertu

2015-04-15

118

Cellulolytic Microorganisms from Thermal Environments  

SciTech Connect

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

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

2012-01-01

119

Vegetative Regeneration Capacities of Five Ornamental Plant Invaders After Shredding.  

PubMed

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

Monty, Arnaud; Eugène, Marie; Mahy, Grégory

2014-11-12

120

Lactobacillus equigenerosi Strain Le1 Invades Equine Epithelial Cells  

PubMed Central

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

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

2012-01-01

121

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

122

Chemically enhanced sunlight for killing bacteria  

SciTech Connect

Solar ultraviolet (UV) photocatalyzed oxidation of chemicals with titanium dioxide (TiO{sub 2}) has received considerable attention. Much less recognized, however, is the ability of the same system to destroy bacteria. This study examined this phenomenon and the conditions that affect it. Bacteria in aqueous solution were given solar exposure with titanium dioxide and their survival with time was determined. Lamps with a predominantly solar ultraviolet spectrum were also used in the experiments. Without exposure to UV light, TiO{sub 2} had no deleterious effect on the bacteria. However, several common bacteria on solar exposure in the presence of TiO{sub 2} were killed in just a few minutes, whereas without TiO{sub 2} it took over an hour to destroy them. A concentration of 0.01% TiO{sub 2} was most effective in killing bacteria and 10-fold concentrations lower or higher were successively less effective. Inorganic and organic compounds in solution, even in small amounts, interfered with the efficiency of killing. Alkaline solution also reduced the bactericidal activity. Circulation and agitation provided by stirring to keep the TiO{sub 2} particles suspended reduced the time necessary to kill the bacteria. Time-intensity curves for killing bacteria were the same general shape with or without TiO{sub 2}, indicating that TiO{sub 2} served merely as a catalyst to increase the rate of the reaction but that the mechanism of action was not changed. The shape of the curves show that the organisms are sensitized with a minimum intensity of radiation and that an increase doesn`t greatly increase the rate of kill. Below this critical intensity, however, the time required for killing markedly increases as the intensity is decreased.

Block, S.S.; Goswami, D.Y. [Univ. of Florida, Gainesville, FL (United States)

1995-10-01

123

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

PubMed

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

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

2014-10-01

124

The remote sensing of microorganisms  

NASA Astrophysics Data System (ADS)

An approach for detecting microbial life in extreme environments, including glacial ice and deep water, using autofluorescence is described. The emission spectra for a variety of microorganisms and common minerals were measured for excitation at 224 nm and it is shown that exciting autofluorescence at 224 nm provides adequate separation between mineral and microbial emission spectra to detect a single microorganism in the glacial ice of Antarctica or on mineral surfaces. The different generations of borehole-logging instruments, dubbed 'biospectral loggers' (BSLs), were designed, built and deployed. The first BSL is a prototype that uses ˜375 nm excitation from UV LEDS and was deployed in the ˜1,000 m deep Siple Dome borehole (January, 2002) and in oligotrophic Lake Tahoe (October, 2002), where microbial NADH, chlorophyll, and dissolved organic matter (DOM) fluorescence was measured. The fluorescence red-shifted with depth, suggesting an increase in of terrestrially-derived DOM with depth, perhaps indicating a benthic source and little recent vertical mixing. The second BSL uses a similar optical geometry as the first, but employs a 224 nm HeAg laser to excite protein fluorescence and was deployed at the SPRESO borehole at the South Pole (January; 2004). It recorded a strong microbial signal corresponding to the time period spanning 1,200 B.P. and 900 B.P., which roughly correlates with major desiccation events in both Patagonia and the Antarctic Dry Valleys, suggesting they may have been aeolian sources of aquatic microorganisms for the South Pole. The third BSL, dubbed the mini-BSL, also uses a 224 nm laser for excitation of protein fluorescence, but its novel optical layout enabled its diameter to be reduced to less than 5.1 cm, allowing it to operate in a borehole produced by a modified JPL 'Gopher' drill[16]. High sensitivity was not sacrificed in the miniaturization process as the mBSL is capable of detecting a single B. megatcrium on a background of iron-rich biotite with a single 100 mus laser pulse. Data demonstrating its sensitivity and other optical parameters are presented and discussed. Suggestions for future upgrades and deployments conclude the dissertation.

Bramall, Nathan Earl

125

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

126

Biocorrosion produced by Thiobacillus-like microorganisms.  

PubMed

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

López, A I; Marín, I; Amils, R

1994-01-01

127

The role of microorganisms in aquaculture ponds  

Microsoft Academic Search

Microorganisms have major roles in pond culture, particularly with respect to productivity, nutrient cycling, the nutrition of the cultured animals, water quality, disease control and environmental impact of the effluent. Management of the activities of microorganisms in food webs and nutrient cycling in ponds is necessary for optimising production, but the objectives will differ with the type of aquaculture, the

David J. W. Moriarty

1997-01-01

128

The evolution of social behavior in microorganisms  

Microsoft Academic Search

Recent studies of microorganisms have revealed diverse complex social behaviors, including cooperation in foraging, building, reproducing, dispersing and communicating. These microorganisms should provide novel, tractable systems for the analysis of social evolution. The application of evolutionary and ecological theory to understanding their behavior will aid in developing better means to control the many pathogenic bacteria that use social interactions to

Bernard J. Crespi

2001-01-01

129

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

130

Generalized Korn's inequality and conformal Killing vectors  

E-print Network

Korn's inequality plays an important role in linear elasticity theory. This inequality bounds the norm of the derivatives of the displacement vector by the norm of the linearized strain tensor. The kernel of the linearized strain tensor are the infinitesimal rigid-body translations and rotations (Killing vectors). We generalize this inequality by replacing the linearized strain tensor by its trace free part. That is, we obtain a stronger inequality in which the kernel of the relevant operator are the conformal Killing vectors. The new inequality has applications in General Relativity.

Sergio Dain

2005-05-04

131

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.

132

HIV transcription is induced with cell killing  

SciTech Connect

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

Woloschak, G.E.; Schreck, S.; Chang-Liu, Chin-Mei [Argonne National Lab., IL (United States); Panozzo, J.; Libertin, C.R. [Loyola Univ. Medical Center, Maywood, IL (United States)

1993-11-01

133

The Vsa proteins modulate susceptibility of Mycoplasma pulmonis to complement killing, hemadsorption, and adherence to polystyrene.  

PubMed

The variable surface antigens (Vsa) of the murine respiratory pathogen Mycoplasma pulmonis are associated with the virulence of the microorganism in the lung. In strain UAB CT, the antigens consist of an N-terminal region that is combined with one of seven different C-terminal variable regions comprised of tandem repeats. M. pulmonis producing a VsaA protein with about 40 tandem repeats (R40) does not adhere to red blood cells or polystyrene. Strains that produce VsaH contain a short C-terminal region that lacks tandem repeats and adhere to red blood cells and plastic. We isolated and analyzed M. pulmonis strain CT variants (CT182 and derivatives) that produced a VsaA protein with only three tandem repeats (R3). These variants adhered to plastic and red blood cells similarly to the VsaH-producing strain. When the R3-producing CT182 strain or the VsaH-producing strains were incubated with normal guinea pig serum, they were efficiently killed. Killing was abolished when the serum was heat inactivated. In contrast, the M. pulmonis strains that produced VsaA R40 were highly resistant to complement killing. CT182R3 variants that survived the complement killing reactions all produced the R40 form of VsaA and were resistant to complement killing. VsaA R40 is the first mycoplasmal protein shown to be associated with resistance to complement. As both VsaH and VsaA can mediate adherence to plastic, cytadherence, and susceptibility to complement, we propose that Vsa modulates these phenotypes by nonspecific interactions. PMID:14500494

Simmons, Warren L; Dybvig, Kevin

2003-10-01

134

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...

135

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 on invasive plants and animals has risen exponentially, little is known about invasive microbes, especially

136

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

137

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

138

Management of Plant Invaders Within a Marsh: An Organizing Principle for Ecological Restoration?  

Microsoft Academic Search

Controlling plant invaders is often one aspect of ecological restoration. However, the planning and application of control\\u000a measures can lead to difficult questions regarding project goals and measures of success. We present a case study of a coastal\\u000a wetland system in South Carolina, USA, where two plant invaders, Phragmites australisand Typha domingensis,were targeted for control. As project participants gradually accepted

James O. Luken; Keith Walters

139

Long-term population dynamics of seeded plants in invaded grasslands.  

PubMed

In recent decades, dozens of studies have involved attempts to introduce native and desirable nonnative plant species into grasslands dominated by invasive weeds. The newly introduced plants have proved capable of establishing, but because they are rarely monitored for more than four years, it is unknown if they have a high likelihood of persisting and suppressing invaders for the long-term. Beyond invaded grasslands, this lack of long-term monitoring is a general problem plaguing efforts to reintroduce a range of taxa into a range of ecosystems. We introduced species from seed and then periodically measured plant abundances for nine years at one site and 15 years at a second site. To our knowledge, our 15-year data are the longest to date from a seeding experiment in invaded, never-cultivated grassland. At one site, three seeded grasses maintained high densities for three or more years, but then all or nearly all individuals died. At the second site, one grass performed similarly, but two other grasses proliferated and at least one greatly suppressed the dominant invader (Centaurea maculosa). In one study, our point estimate suggests that the seeded grass Thinopyrum intermedium reduced C. maculosa biomass by 93% 15 years after seeding. In some cases, data from three and fewer years after seeding falsely suggested that seeded species were capable of persisting within the invaded grassland. In other cases, data from as late as nine years after seeding falsely suggested seeded populations would not become large enough to suppress the invader. These results show that seeded species sometimes persist and suppress invaders for long periods, but short-term data cannot predict if, when, or where this will occur. Because short-term data are not predictive of long-term seeded species performances, additional long-term data are needed to identify effective practices, traits, and species for revegetating invaded grasslands. PMID:22827138

Rinella, Matthew J; Mangold, Jane M; Espeland, Erin K; Sheley, Roger L; Jacobs, James S

2012-06-01

140

Challenging Xanthomonas campestris with low levels of arsenic mediates cross-protection against oxidant killing.  

PubMed

Xanthomonas encounters highly toxic reactive oxygen species (ROS) from many sources, such as those generated by plants against invading bacteria, other soil bacteria and from aerobic respiration. Thus, conditions that alter intracellular ROS levels such as exposure to toxic metalloids would have profound effects on bacterial physiology. Here, we report that exposure of Xanthomonas campestris pv. phaseoli (Xp) to low levels of arsenic induces physiological cross-protection against killing by H(2)O(2) and organic hydroperoxide but not a superoxide generator. Cross-protection against H(2)O(2) and organic hydroperoxide toxicity was due to increased expression of genes encoding major peroxide-metabolizing enzymes such as alkyl hydroperoxide reductase (AhpC), catalase (KatA) and organic hydroperoxide resistance protein (Ohr). Arsenic-induced protection against H(2)O(2) and organic hydroperoxide requires the peroxide stress response regulators, OxyR and OhrR, respectively. Moreover, analyses of double mutants of the major H(2)O(2) and organic hyproperoxide-scavenging enzymes, Xp ahpC katA and Xp ahpC ohr, respectively, suggested the existence of unidentified OxyR- and OhrR-regulated genes that are involved in arsenic-induced resistance to H(2)O(2) and organic hyproperoxide killing in Xp. These arsenic-induced physiological alterations could play an important role in bacterial survival both in the soil environment and during plant-pathogen interactions. PMID:16907748

Hrimpeng, Karnjana; Prapagdee, Benjaphorn; Banjerdkij, Peerakan; Vattanaviboon, Paiboon; Dubbs, James M; Mongkolsuk, Skorn

2006-09-01

141

Lantibiotic production by pathogenic microorganisms.  

PubMed

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

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

2012-09-01

142

The Evolution of Reduced Microbial Killing  

PubMed Central

Bacteria engage in a never-ending arms race in which they compete for limited resources and niche space. The outcome of this intense interaction is the evolution of a powerful arsenal of biological weapons. Perhaps the most studied of these are colicins, plasmid-based toxins produced by and active against Escherichia coli. The present study was designed to explore the molecular responses of a colicin-producing strain during serial transfer evolution. What evolutionary changes occur when colicins are produced with no target present? Can killing ability be maintained in the absence of a target? To address these, and other, questions, colicinogenic strains and a noncolicinogenic ancestor were evolved for 253 generations. Samples were taken throughout the experiment and tested for killing ability. By the 38th transfer, a decreased killing ability and an increase in fitness were observed in the colicin-producing strains. Surprisingly, DNA sequence determination of the colicin plasmids revealed no changes in plasmid sequences. However, a set of chromosomally encoded loci experienced changes in gene expression that were positively associated with the reduction in killing. The most significant expression changes were observed in DNA repair genes (which were downregulated in the evolved strains), Mg ion uptake genes (which were upregulated), and late prophage genes (which were upregulated). These results indicate a fine-tuned response to the evolutionary pressures of colicin production, with far more genes involved than had been anticipated. PMID:20333208

Valliere, Michael; Riley, Margaret A.

2009-01-01

143

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.

144

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

145

Advanced gel propulsion controls for kill vehicles  

Microsoft Academic Search

A gel propulsion control concept for tactical applications is reviewed, and the status of the individual component technologies currently under development at the Aerojet Propulsion Division is discussed. It is concluded that a gel propellant Divert and Attitude Control Subsystem (DACS) provides a safe, insensitive munitions compliant alternative to current liquid Theater Missile Defense (TMD) DACS approaches. The gel kill

W. K. Yasuhara; A. Olson; S. Finato

1993-01-01

146

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

147

MECHANISM BY WHICH AMMONIUM FERTILIZERS KILL LARKSPUR  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

148

killed-virus influenza vaccine Polio vaccine  

E-print Network

killed-virus influenza vaccine Polio vaccine FluMist Thomas Francis, Jr. National Institutes of Health live-virus influenza vaccine Hunein Maassab Jonas Salk Type-A virus trivalent cold that Maassab's innovative, trivalent, cold- adapted influenza vaccine, FluMist, which uses live but weakened

Shyy, Wei

149

[Molecular karyotyping of eukaryotic microorganisms].  

PubMed

In many fungi and protists small size and weak morphological differentiation of chromosomes embarrass the study of karyotypes using microscopical tools. Molecular karyotyping based on the fractionation of intact chromosomal DNAs by pulsed field gel electrophoresis (PFGE) provides an alternative approach to the analysis of chromosomal sets in such organisms. To assign the bands observed in PFGE gel to the individual chromosomes the following methods of chromosome identification are applied: densitometric analysis of the bands; Southern hybridization with chromosome- and telomere-specific probes, which often is combined with comparative karyotyping of a series of strains with pronounced size polymorphism of chromosomes; comparison of the patterns of restriction fragments of chromosomal DNAs fractioned by KARD 2-D PFGE; comparison with the strains with well-studied interchromosomal rearrangements. Besides estimation of the number and the size of chromosomes, molecular karyotyping allows assessment of haploid genome size and ploidy level, study of genome dynamics, identification of chromosomal rearrangements and associated chromosomal polymorphism. The analysis of karyotype and dynamics of the genomes is important for the study of intra- and interspecial variability, investigation of the chromosome evolution in closely related species and elaboration of the models of speciation. The comparison of molecular karyotypes among isolates of different origin is of great practical importance for clinical diagnostics and for agricultural microbiology. In this review we discuss: 1) the methods of karyotyping and their application to the analysis of chromosomal sets in eukaryotic microorganisms; 2) the specificity of the methods used for extraction and fractionation of intact chromosomal DNAs; 3) the reasons for difficulties in interpretation of molecular karyotypes and the ways of their overcoming; 4) fields of application of molecular karyotyping; 5) the definition of "molecular karyotype" formulated in accordance with modern methodological requirements. PMID:23285725

Nasonova, E S

2012-01-01

150

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

151

Detection of microorganisms using terahertz metamaterials  

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

152

PARTICLE-ASSOCIATED MICROORGANISMS IN STORMWATER RUNOFF  

EPA Science Inventory

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

153

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

154

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

155

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

156

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

157

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

158

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

159

9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.  

Code of Federal Regulations, 2014 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...

2014-01-01

160

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

161

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

162

9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2014 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...

2014-01-01

163

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

164

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

165

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

166

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

167

9 CFR 113.208 - Avian Encephalomyelitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2014 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...

2014-01-01

168

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

169

9 CFR 113.206 - Wart Vaccine, Killed Virus.  

Code of Federal Regulations, 2014 CFR

...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

170

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

171

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

172

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

173

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

174

9 CFR 113.216 - Bovine Rhinotracheitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2011 CFR

...Bovine Rhinotracheitis Vaccine, Killed Virus. 113.216 Section 113.216 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.216 Bovine...

2011-01-01

175

A single Photorhabdus gene, makes caterpillars floppy (mcf), allows Escherichia coli to persist within and kill insects  

PubMed Central

Photorhabdus luminescens, a bacterium with alternate pathogenic and symbiotic phases of its lifestyle, represents a source of novel genes associated with both virulence and symbiosis. This entomopathogen lives in a “symbiosis of pathogens” with nematodes that invade insects. Thus the bacteria are symbiotic with entomopathogenic nematodes but become pathogenic on release from the nematode into the insect blood system. Within the insect, the bacteria need to both avoid the peptide- and cellular- (hemocyte) mediated immune response and also to kill the host, which then acts as a reservoir for bacterial and nematode reproduction. However, the mechanisms whereby Photorhabdus evades the insect immune system and kills the host are unclear. Here we show that a single large Photorhabdus gene, makes caterpillars floppy (mcf), is sufficient to allow Esherichia coli both to persist within and kill an insect. The predicted high molecular weight Mcf toxin has little similarity to other known protein sequences but carries a BH3 domain and triggers apoptosis in both insect hemocytes and the midgut epithelium. PMID:12136122

Daborn, P. J.; Waterfield, N.; Silva, C. P.; Au, C. P. Y.; Sharma, S.; ffrench-Constant, R. H.

2002-01-01

176

Characterization of Phosphorus Forms in Soil Microorganisms  

Microsoft Academic Search

\\u000a Characterization of phosphorus (P) forms in soil microorganisms is a novel approach to reach a better understanding of the\\u000a role of bacteria and fungi as sink and source of P. After an overview of methods for cultivation of microorganisms, extraction\\u000a from soil, and chemical analysis, two case studies are presented, one on pure cultures and one on microbial cells extracted

Else K. Bünemann; Bartlomiej Prusisz; Knut Ehlers

177

Nitrogen fixing microorganisms in paddy soils XII  

Microsoft Academic Search

IntroductionWe have been studying the interrelation between R. capsulatus and other various microorganisms, in which there are symbiotic relationships (I). When R. capsulatlls and Az. vinelandii co-existed, molecular nitrogen was fixed much more than in each pure culture and many slime substances (polysaccharides, muco-polysaccharides etc.) were produced (2). In order to study symbiotic nitrogen fixation between the two microorganisms, first,

Azuma Okuda; Michiharu Kobayashi; Konoshin Onodera; Michio Himeno

1964-01-01

178

Conformal killing tensors and covariant Hamiltonian dynamics  

NASA Astrophysics Data System (ADS)

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

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

2014-12-01

179

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

180

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

181

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.

182

HIV transcription is induced with cell killing  

SciTech Connect

Previous work has shown that HeLa cells stably transfected with an HIV-LTR-CAT construct are induced to express chloramphenicol acetyl transferase (CAT) following exposure to DNA-damaging agents such as ultraviolet radiation, {gamma} rays, neutrons, and others. In this report, the authors demonstrate that this induction of HIV-LTR transcription occurs when stably transfected HeLa cells are exposed to agents which mediate cell killing, such as UV radiation, electroporation of sucrose buffer, prolonged heating, and low and high pH. Cells cultured following UV exposure demonstrated a peak in CAT expression that is evidence in viable (but not necessarily cell division-competent) cells 24 h after exposure; this inductive response continued until at least 72 h after exposure. HIV-LTR induction was dose-dependent, and the amount of CAT transcription induced was correlated with the amount of cell killing that occurred in the culture. Other agents which caused no cell killing (such as heat-shock for up to 2 h, treatment with metronidazole, exposure to sunlight, vitamin C treatment, and others) had no effect on HIV-LTR induction. These results suggest that HIV transcription is induced as a consequence of the turn on of a cellular death or apoptotic pathway.

Woloschak, G.E.; Schreck, S.; Chang-Liu, Chin Mei [Argonne National Lab., IL (United States); Panozzo, J. [Loyola Univ. Medical Center, Maywood, IL (United States). Dept. of Pathology; Libertin, C.R. [Loyola Univ. Medical Center, Maywood, IL (United States)

1994-01-01

183

Designing surfaces that kill bacteria on contact  

NASA Astrophysics Data System (ADS)

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

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

2001-05-01

184

Immune Response to Orally Administered Killed MAP in Calves  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of this study was to determine whether orally administered heat-killed MAP could induce a protective immune response in calves. Newborn male dairy calves were randomly assigned to one of 4 treatment groups: Heat killed MAP only (n=2), live MAP challenge only (n=4), heat killed MAP fo...

185

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

186

Inhomogeneous problems Q. How do you kill a blue elephant?  

E-print Network

Inhomogeneous problems Q. How do you kill a blue elephant? A. With a blue elephant gun Q. How do you kill a pink elephant? A. Squeeze its trunk until it turns blue, and then shoot it with a blue elephant gun. Q. How do you kill a white elephant? A. Tickle it pink, then squeeze its trunk until it turns

DeTurck, Dennis

187

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

188

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

NASA Astrophysics Data System (ADS)

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

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

2013-03-01

189

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

190

Improving photodynamic inactivation of bacteria in dentistry: highly effective and fast killing of oral key pathogens with novel tooth-colored type-II photosensitizers.  

PubMed

Increasing antibiotic resistances in microorganisms create serious problems in public health. This demands alternative approaches for killing pathogens to supplement standard treatment methods. Photodynamic inactivation of bacteria (PIB) uses light activated photosensitizers (PS) to generate reactive oxygen species immediately upon illumination, inducing lethal phototoxicity. Positively charged phenalen-1-one derivatives are a new generation of PS for light-mediated killing of pathogens with outstanding singlet oxygen quantum yield ?? of >97%. Upon irradiation with a standard photopolymerizer light (bluephase C8, 1260 ± 50 mW/cm(2)) the PS showed high activity against the oral key pathogens Enterococcus faecalis, Actinomyces naeslundii, Streptococcus mutans, and Aggregatibacter actinomycetemcomitans. At a concentration of 10 ?M, a maximum efficacy of more than 6 log10 steps (? 99.9999%) of bacteria killing is reached in less than 1 min (light dose 50 J/cm(2)) after one single treatment. The pyridinium substituent as positively charged moiety is especially advantageous for antimicrobial action. PMID:24884918

Späth, Andreas; Leibl, Christoph; Cieplik, Fabian; Lehner, Karin; Regensburger, Johannes; Hiller, Karl-Anton; Bäumler, Wolfgang; Schmalz, Gottfried; Maisch, Tim

2014-06-26

191

Micro-sociology of mass rampage killings.  

PubMed

Spectacular but very rare violent events such as mass killings by habitual non-criminals cannot be explained by factors which are very widespread, such as possession of firearms, being a victim of bullying, an introvert, or a career failure. A stronger clue is clandestine preparation of attack by one or two individuals, against randomly chosen representatives of a hated collective identity. Mass killers develop a deep back-stage, obsessed with planning their attack, overcoming social inferiority and isolation by an emotion of clandestine excitement. PMID:25179819

Collins, Randall

2014-09-01

192

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

193

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

194

Microorganism Utilization for Synthetic Milk Production  

NASA Technical Reports Server (NTRS)

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

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

2014-01-01

195

Systemic diseases caused by oral microorganisms.  

PubMed

Human endodontic and periodontal infections are associated with complex microfloras in which approximately 150, (in apical periodontitis) and 350 (in marginal periodontitis) bacterial species have been encountered. These infections are predominantly anaerobic, with gram-negative rods being the most common isolates. The anatomic closeness of this microflora to the bloodstream can facilitate bacteremia and systemic spread of bacterial by-products and immunocomplexes. A variety of clinical procedures such as tooth extraction, periodontal and endodontic treatment, may cause translocation of microorganisms from the oral cavity to the bloodstream. The microorganisms that gain entrance to the blood circulate throughout the body, but are usually eliminated by the host (reticuloendothelial system) within minutes. However, in patients with ineffective heart valves or vascular diseases, bacteremia can be a potential danger, leading most commonly to infective endocarditis and myocardial or cerebral infarction. Other forms of systemic diseases such as brain abscesses, hematological infections and implant infections have also been related to oral microorganisms. PMID:8062808

Debelian, G J; Olsen, I; Tronstad, L

1994-04-01

196

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

197

Microorganisms in the aetiology of atherosclerosis  

PubMed Central

Recent publications have suggested that infective pathogens might play an important role in the pathogenesis of atherosclerosis. This review focuses on these microorganisms in the process of atherosclerosis. The results of in vitro studies, animal studies, tissue studies, and serological studies will be summarised, followed by an overall conclusion concerning the strength of the association of the microorganism with the pathogenesis of atherosclerosis. The role of the bacteria Chlamydia pneumoniae and Helicobacter pylori, and the viruses human immunodeficiency virus, coxsackie B virus, cytomegalovirus, Epstein-Barr virus, herpes simplex virus, and measles virus will be discussed. Key Words: atherosclerosis • Chlamydia pneumoniae • Helicobacter pylori PMID:11041053

Morre, S; Stooker, W; Lagrand, W; van den Brule, A J C; Niessen, H

2000-01-01

198

[Tinctorial properties of microorganisms isolated from blood].  

PubMed

Cultures isolated from human and animal blood have been examined in tests with 3% KOH solution; their sensitivities to various concentrations of sulfanol have been tested in order to specify the tinctorial characteristics of these cultures; antibiotic sensitivity of this group of microorganisms has been studied with the use of discs. The findings evidence that gram-variable nonspore-carrying aerobic bacilli isolated from human and animal blood should be referred to gram-positive microorganisms; their antibiotic sensitivity has been detected. The tests employed in the study may be rationally used for the identification of polychromic bacteria isolated from the blood. PMID:2470973

Andreeva, Z M; Ershova, E B; Khramova, N I; Barkhudarian, B A

1989-01-01

199

Hydrodynamic Phase Locking of Swimming Microorganisms  

NASA Astrophysics Data System (ADS)

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

Elfring, Gwynn J.; Lauga, Eric

2009-08-01

200

Metabolic activity of microorganisms in evaporites.  

PubMed

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

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

1994-06-01

201

Ants are among the most prevalent pests in households. Ants also invade restau-  

E-print Network

Ants are among the most prevalent pests in households. Ants also invade restau- rants, hospitals indoor plants, ants protect and care for honeydew-producing insects such as aphids, soft scales, whiteflies, and mealy- bugs, increasing damage from these pests. Ants also perform many useful functions

Ishida, Yuko

202

Dispersal and demography contributions to population spread of Carduus nutans in its native and invaded ranges  

Microsoft Academic Search

Summary 1. Invasive species usually exhibit different spatial population dynamics in their native and invaded range. This is often attributed to demographic differences, but may be due to differences in dispersal as well. 2. Regardless of how these dispersal and demographic differences from the native range arose, studying how they contributed to increases in population spread rates will increase our

Eelke Jongejans; Katriona Shea; Olav Skarpaas; Dave Kelly; Andy W. Sheppard; Tim L. Woodburn

2008-01-01

203

Response of semi-desert grasslands invaded by non-native grasses to altered  

E-print Network

ORIGINAL ARTICLE Response of semi-desert grasslands invaded by non-native grasses to altered disturbance regimes Erika L. Geiger* and Guy R. McPherson INTRODUCTION Similar to other biomes across the globe, grasslands in the American Southwest have experienced significant changes to their historic

Binford, Michael W.

204

Wadden Sea mussel beds invaded by oysters and slipper limpets: competition or climate control?  

NASA Astrophysics Data System (ADS)

Introduced species are often considered to be a threat to residents, but not all reciprocal trends may reflect species interaction. In the northern German Wadden Sea, native mussel Mytilus edulis beds are declining and overgrown by introduced Pacific oysters Crassostrea gigas and slipper limpets Crepidula fornicata. We review the population development of the three species and analyse whether the invading species may be responsible for the decline of native mussels. The Pacific oyster predominately settles on mussel beds in the intertidal and the slipper limpet dominates around low water line. We compare the development of mussels and invaders in two subregions: mussel beds near the islands of Sylt and Amrum decreased both in the presence (Sylt) and absence (Amrum) of the two invading species and more detailed investigations could not confirm a causal relationship between the increasing invaders and decreasing mussel beds. There is evidence that the decline of mussel beds is mainly caused by failing spatfall possibly due to mild winters, whereas the increase in slipper limpets and oysters is facilitated by mild winters and warm summers, respectively. We conclude that changing species composition is a result of the climatic conditions in the last decade and that there is no evidence yet that the exotic species caused the decline of the natives. It remains an open question whether the species shift will continue and what the consequences for the native ecosystem will be.

Nehls, Georg; Diederich, Susanne; Thieltges, David W.; Strasser, Matthias

2006-05-01

205

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

USGS Publications Warehouse

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

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

2000-01-01

206

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

207

Differential influence of Pomphorhynchus laevis (Acanthocephala) on the behaviour of native and invader gammarid species  

Microsoft Academic Search

Although various species of acanthocephalan parasites can increase the vulnerability of their amphipod intermediate hosts to predation, particularly by altering their photophobic behaviour, their influence on the structure of amphipod communities and the success of invader species has so far received little attention. We compared the prevalence and behavioural influence of a fish acanthocephalan parasite, Pomphorhynchus laevis, in two species

Alexandre Bauer; Sandrine Trouvé; Arnaud Grégoire; Frank Cézilly

2000-01-01

208

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

209

The genus Acacia as invader: the characteristic case of Acacia dealbata Link in Europe  

Microsoft Academic Search

– \\u000a \\u000a • We review current knowledge about the biology of the genus Acacia, and Acacia dealbata Link (silver wattle) in particular, as an invader in Europe, focusing on (i) the biology of the genus Acacia; (ii) biological attributes that are important for the invasiveness of the genus and A. dealbata; (iii) possible hypotheses for the invasion success; and (iv) control

Paula Lorenzo; Luís González; Manuel J. Reigosa

2010-01-01

210

A generic risk-based surveying method for invading plant pathogens  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

211

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

212

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

213

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

214

Diluting the founder effect: cryptic invasions expand a marine invader's range  

E-print Network

Diluting the founder effect: cryptic invasions expand a marine invader's range Joe Roman Ecology of Invasions of Animals and Plants, this momentum has continued to grow. Although fouled ships & Geller 1993; Carlton 2001; Chapman et al. 2004). As a result, the rate of marine invasions has risen

Vermont, University of

215

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

ERIC Educational Resources Information Center

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

Lampert, Evan

2015-01-01

216

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

217

Total vertebrectomy for en bloc resection of lung cancer invading the spine.  

PubMed

We describe a technique of total vertebrectomy for en bloc resection of a non-small cell lung cancer with vertebral invasion through a combination of thoracic and enlarged posterior approaches, and present our entire experience of total and partial vertebrectomy for tumors invading vertebral bodies or the costovertebral angle. PMID:8572801

Grunenwald, D; Mazel, C; Girard, P; Berthiot, G; Dromer, C; Baldeyrou, P

1996-02-01

218

Root-invading fungi of milk vetch on the Loess Plateau, China  

Microsoft Academic Search

Root-invading fungi of milk vetch (Astragalus adsurgens) at different growth stages grown in three ages of sown pasture soil were studied in Huanxian county, Gansu province, China. Pathogenicity was tested by seed and soil inoculation. A total of 44 fungi were isolated from milk vetch roots, 32 from the roots of field plants and 37 from the roots of potted

Yali Yin; Z. B. Nan; Chunjie Li; Fujiang Hou

2008-01-01

219

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

220

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

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

2009-01-01

221

Performance and reproduction of an exotic invader across temperate forest gradients  

E-print Network

Performance and reproduction of an exotic invader across temperate forest gradients ROBERT J of Biological Sciences, Wright State University, Dayton, Ohio 45435 USA Abstract. Widespread colonization investigated recruitment in the context of experimental and natural disturbances. We find that all habitats

Bahn, Volker

222

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

223

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

E-print Network

geographic distribution from Australia and Japan, through the Indian Ocean to East Africa and the Red Sea that are invading the Mediterranean from the Red Sea via the Suez Canal. We PCR amplified and sequenced Sea. We found that the two Red Sea populations are likely to correspond to two previously undescribed

Bernardi, Giacomo

224

Stats invaders!: learning about statistics by playing a classic video game  

Microsoft Academic Search

This poster describes a computer game designed to provide players with exposure to repeated draws from probability distributions. In the game, players shoot aliens dropping from the sky (as in the classic arcade game Space Invaders) while deciding which of two displayed distributions better reflects the pattern of the alien attack. Our hypothesis is that playing this version of the

Dylan Arena; Daniel L. Schwartz

2010-01-01

225

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

226

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

227

Estimation of dynamic petrophysical properties of water-bearing sands invaded with oil-base mud from the interpretation  

E-print Network

Estimation of dynamic petrophysical properties of water-bearing sands invaded with oil-base mud dynamic petrophysical properties in the water-bearing portion of the reservoir are in agreement) invades connate water- saturated rocks. This is a favorable condition for the estimation of dynamic

Torres-Verdín, Carlos

228

Radiation sensitivity of hyperthermal composting microorganisms  

NASA Astrophysics Data System (ADS)

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

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

229

Metagenomics: Application of Genomics to Uncultured Microorganisms  

PubMed Central

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

Handelsman, Jo

2004-01-01

230

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

231

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

232

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.

233

Measuring micro-organism gas production  

NASA Technical Reports Server (NTRS)

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

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

1973-01-01

234

Microorganism lipid droplets and biofuel development.  

PubMed

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

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

2013-12-01

235

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...

236

Resistance responses of microorganisms in food environments  

Microsoft Academic Search

Food borne microorganisms display a broad spectrum of resistance responses to naturally occurring and intentionally added antimicrobial agents. Resistance may be conferred by innate structural features of the bacterial strain such as an impermeable outer membrane or a mechanism for antibiotic-inactivation. Bacteria previously susceptible to an antimicrobial compound can acquire resistance through mutation or through genetic transfer processes such as

C. K Bower; M. A Daeschel

1999-01-01

237

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

238

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

239

Killing vectors in algebraically special space-times  

SciTech Connect

The form of the isometric, homothetic, and conformal Killing vectors for algebraically special metrics which admit a shear-free congruence of null geodesics is obtained by considering their complexification, using the existence of a congruence of null strings. The Killing equations are partially integrated and the reasons which permit this reduction are exhibited. In the case where the congruence of null strings has a vanishing expansion, the Killing equations are reduced to a single master equation.

Torres del Castillo, G.F.

1984-06-01

240

Opportunities for renewable bioenergy using microorganisms.  

PubMed

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

Rittmann, Bruce E

2008-06-01

241

The Production of Antibody by Invading B Cells Is Required for the Clearance of Rabies Virus from the Central Nervous System  

PubMed Central

Background The pathogenesis of rabies is associated with the inability to deliver immune effectors across the blood-brain barrier and to clear virulent rabies virus from CNS tissues. However, the mechanisms that facilitate immune effector entry into CNS tissues are induced by infection with attenuated rabies virus. Methodology/Principal Findings Infection of normal mice with attenuated rabies virus but not immunization with killed virus can promote the clearance of pathogenic rabies virus from the CNS. T cell activity in B cell–deficient mice can control the replication of attenuated virus in the CNS, but viral mRNA persists. Low levels of passively administered rabies virus–neutralizing antibody reach infected cells in the cerebellum of B cell–deficient mice but are not sufficient to mediate virus clearance. Production of rabies virus-specific antibody by B cells invading CNS tissues is required for this process, and a substantial proportion of the B cells that accumulate in the CNS of mice infected with attenuated rabies virus produce virus-specific antibodies. Conclusions/Significance The mechanisms required for immune effectors to enter rabies virus-infected tissues are induced by infection with attenuated rabies virus but not by infection with pathogenic rabies viruses or immunization with killed virus. T cell activities can inhibit rabies virus replication, but the production of rabies virus–specific antibodies by infiltrating B cells, as opposed to the leakage of circulating antibody across the BBB, is critical to elimination of the virus. These findings suggest that a pathogenic rabies virus infection may be treatable after the virus has reached the CNS tissues, providing that the appropriate immune effectors can be targeted to the infected tissues. PMID:19806203

Hooper, D. Craig; Phares, Timothy W.; Fabis, Marzena J.; Roy, Anirban

2009-01-01

242

Killing forms and toric Sasaki-Einstein spaces  

NASA Astrophysics Data System (ADS)

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

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

2014-11-01

243

Killing acanthamoebae with polyaminopropyl biguanide: quantitation and kinetics.  

PubMed Central

The two Acanthamoeba species most often implicated in corneal keratitis, A. castellanii and A. polyphaga, were exposed as cysts to polyaminopropyl biguanide (PAPB), a commonly used antimicrobial agent. Killing of amoeba cysts was rapid and extensive, with fewer than 2% of either species surviving 30 s of exposure to > or = 45 ppm of PAPB. Killing kinetics were biphasic, and further exposures of 15 min to 1 h killed greater than 90% of those surviving initial killing. This potency of PAPB, together with its low toxicity to humans when ingested or applied topically, underscores the potential of PAPB as an antiamoebic agent. PMID:8031066

Burger, R M; Franco, R J; Drlica, K

1994-01-01

244

Advanced gel propulsion controls for kill vehicles  

NASA Astrophysics Data System (ADS)

A gel propulsion control concept for tactical applications is reviewed, and the status of the individual component technologies currently under development at the Aerojet Propulsion Division is discussed. It is concluded that a gel propellant Divert and Attitude Control Subsystem (DACS) provides a safe, insensitive munitions compliant alternative to current liquid Theater Missile Defense (TMD) DACS approaches. The gel kill vehicle (KV) control system packages a total impulse typical of a tactical weapon interceptor for the ground- or sea-based TMD systems. High density packaging makes it possible to increase firepower and to eliminate long-term high pressure gas storage associated with bipropellant systems. The integrated control subsystem technologies encompass solid propellant gas generators, insulated composite overwrapped propellant tanks, lightweight endoatmospheric thrusters, and insensitive munition gel propellants, which meet the requirements of a deployable, operationally safe KV.

Yasuhara, W. K.; Olson, A.; Finato, S.

1993-06-01

245

Kill the Bacteria … and Also Their Messengers?  

PubMed Central

We consider here a previously neglected aspect of recovery from infectious diseases: how animals dispose of the dead microbes in their tissues. For one of the most important disease-causing microorganisms, Gram-negative bacteria, there is now evidence that the host catabolism of a key microbial molecule is essential for full recovery. As might be expected, it is the same bacterial molecule that animals sense to detect the presence of Gram-negative bacteria in their tissues, the cell wall lipopolysaccharide (LPS). Here, we discuss current knowledge about LPS sensing with emphasis on the host enzyme that inactivates this microbial “messenger” molecule. We also consider the possibility that the rate at which stimulatory microbial molecules undergo inactivation may influence the duration and severity of diseases caused by other infectious agents. PMID:19755182

Munford, Robert; Lu, Mingfang; Varley, Alan

2009-01-01

246

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

247

ESTIMATING MICROORGANISM DENSITIES IN AEROSOLS FROM SPRAY IRRIGATION OF WASTEWATER  

EPA Science Inventory

This document summarizes current knowledge about estimating the density of microorganisms in the air near wastewater management facilities, with emphasis on spray irrigation sites. One technique for modeling microorganism density in air is provided and an aerosol density estimati...

248

MICROORGANISMS DIE-OFF RATES IN URBAN STORMWATER RUNOFF 2007  

EPA Science Inventory

Stormwater best management practices (BMPs) are often considered effective tools to mitigate the effects of stormwater pollutants before they are discharged to receiving waters. However, BMP performance for microorganisms removal is not well documented. Microorganisms die-off in...

249

MICROORGANISMS DIE-OFF RATES IN URBAN STORMWATER RUNOFF 2007  

EPA Science Inventory

Stormwater best management practices (BMPs) are often considered effective tools to mitigate the effects of stormwater pollutants before they are discharged to receiving waters. However, BMP performance for microorganisms removal is not well documented. Microorganisms die-off in ...

250

Origins of Halophilic Microorganisms in Ancient Salt Deposits  

NSDL National Science Digital Library

This eight-page review article considers the evidence for and against long-term survival of halophilic microorganisms in ancient salt deposits. Included sections are hypersaline environments and their inhabitants, haloarchaea and halite precipitation, isolations of microorganisms from brines in salt mines, isolations of microorganisms from ancient rock salt, isolations of microorganisms directly from fluid inclusions, relationship of subsurface haloarchaea to surface isolates, dispersal of haloarchaea, and long-term survival of haloarchaea inside salt crystals.

Mcgenity, Terry; Gemmell, Renia; Grant, William; Stan-Lotter, Helga; Microbiology, Environmental

251

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

PubMed Central

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

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

2014-01-01

252

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.

2012-03-05

253

Microorganisms detection on substrates using QCL spectroscopy  

NASA Astrophysics Data System (ADS)

Recent investigations have focused on the improvement of rapid and accurate methods to develop spectroscopic markers of compounds constituting microorganisms that are considered biological threats. Quantum cascade lasers (QCL) systems have revolutionized many areas of research and development in defense and security applications, including his area of research. Infrared spectroscopy detection based on QCL was employed to acquire mid infrared (MIR) spectral signatures of Bacillus thuringiensis (Bt), Escherichia coli (Ec) and Staphylococcus epidermidis (Se), which were used as biological agent simulants of biothreats. The experiments were carried out in reflection mode on various substrates such as cardboard, glass, travel baggage, wood and stainless steel. Chemometrics statistical routines such as principal component analysis (PCA) regression and partial least squares-discriminant analysis (PLS-DA) were applied to the recorded MIR spectra. The results show that the infrared vibrational techniques investigated are useful for classification/detection of the target microorganisms on the types of substrates studied.

Padilla-Jiménez, Amira C.; Ortiz-Rivera, William; Castro-Suarez, John R.; Ríos-Velázquez, Carlos; Vázquez-Ayala, Iris; Hernández-Rivera, Samuel P.

2013-05-01

254

Distribution of Aldoxime Dehydratase in Microorganisms  

PubMed Central

The distribution of phenylacetaldoxime-degrading and pyridine-3-aldoxime-degrading ability was examined with intact cells of 975 microorganisms, including 45 genera of bacteria, 11 genera of actinomyces, 22 genera of yeasts, and 37 genera of fungi, by monitoring the decrease of the aldoximes by high-pressure liquid chromatography. The abilities were found to be widely distributed in bacteria, actinomyces, fungi, and some yeasts: 98 and 107 strains degraded phenylacetaldoxime and pyridine-3-aldoxime, respectively. All of the active strains exhibited not only the aldoxime-dehydration activity to form nitrile but also nitrile-hydrolyzing activity. On the other hand, all of 19 nitrile-degrading microorganisms (13 species, 7 genera) were found to exhibit aldoxime dehydration activity. It is shown that aldoxime dehydratase and nitrile-hydrolyzing activities are widely distributed among 188 aldoxime and 19 nitrile degraders and that the enzymes were induced by aldoximes or nitriles. PMID:10831401

Kato, Yasuo; Ooi, Ryoko; Asano, Yasuhisa

2000-01-01

255

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

256

UV inactivation of pathogenic and indicator microorganisms  

SciTech Connect

Survival was measured as a function of the dose of germicidal UV light for the bacteria Escherichia coli, Salmonella typhi, Shigella sonnei, Streptococcus faecalis, Staphylococcus aureus, and Bacillus subtilis spores, the enteric viruses poliovirus type 1 and simian rotavirus SA11, the cysts of the protozoan Acanthamoeba castellanii, as well as for total coliforms and standard plate count microorganisms from secondary effluent. The doses of UV light necessary for a 99.9% inactivation of the cultured vegetative bacteria, total coliforms, and standard plate count microorganisms were comparable. However, the viruses, the bacterial spores, and the amoebic cysts required about 3 to 4 times, 9 times, and 15 times, respectively, the dose required for E. coli. These ratios covered a narrower relative dose range than that previously reported for chlorine disinfection of E. coli, viruses, spores, and cysts.

Chang, J.C.; Ossoff, S.F.; Lobe, D.C.; Dorfman, M.H.; Dumais, C.M.; Qualls, R.G.; Johnson, J.D.

1985-06-01

257

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

258

Invading Cancer Cells Share the Metabolic Burden | Physical Sciences in Oncology  

Cancer.gov

Metastatic cancer cells are able to cut through the dense extracellular collagen matrix that surround tumors, but doing so comes at a significant energy cost. Now, using a novel synthetic microenvironment to observe how groups of metastatic breast tumor cells move cooperatively in three dimensions, researchers have found that invading cancer cells follow the same strategy as geese do when traveling long distances through the air.

259

Science Sampler: Alien Invaders! A board game about the threats posed by introduced species  

NSDL National Science Digital Library

Alien Invaders!--loosely modeled after the game of Life, helps students to understand how introduced species can affect native species. This board game allows students to role-play native birds in a world of introduced species, facing the hazards posed by those species. By playing this game, students come to understand some of the effects, such as competition and predation, of invasive species on native species.

Stracey, Christine

2008-02-01

260

"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

261

Masters graduation project COLLECTIVE MOTION OF MICRO-ORGANISMS  

E-print Network

Masters graduation project COLLECTIVE MOTION OF MICRO-ORGANISMS Investigation of flow patterns induced by the collective motion of micro- organisms Problem: Dense suspensions of micro-organisms have fraction as well as the details of the swimming mechanisms of the micro-organisms. Project: This project

Lindken, Ralph

262

Phototoxicity of skin microorganisms tested with a new model  

Microsoft Academic Search

A new standardized method for testing phototoxicity of chemicals against microorganisms is described. The inoculum size of the microorganism, application of test chemicals, prediffusion time, incubation time and incubation period are defined. Staphylococcus aureus, S. epidermidis, Candida albicans, and Pityrosporum orbiculare were studied. Both 8-methoxypsoralen and trimethylpsoralen were phototoxic against all microorganisms tested, while tetracycline and doxycycline were not phototoxic.

J. Faergemann; O. Larkö

1988-01-01

263

Metagenomics - An advanced approach for non- cultivable micro-organisms  

Microsoft Academic Search

It is known that only 0.1 - 10% of all microorganisms observed in nature can be cultured under conventional laboratory conditions. This leaves researchers unable to study more than 99% of microorganisms in some environments - microorganisms that sometimes have unique and potentially very useful abilities such as waste degradation or synthesis of compounds that could find use as drugs

Majid R. Kamli; Badrul Islam; Mohammed Atif; Faheem A Benkhayal; M. Nehal; M. A. Rizvi; Arif Ali

2009-01-01

264

FACTORS AFFECTING SECONDARY KILL OF THE GERMAN COCKROACH (DICTYOPTERA  

E-print Network

153 FACTORS AFFECTING SECONDARY KILL OF THE GERMAN COCKROACH (DICTYOPTERA: BLATTELLIDAE) BY GEL of Forestry, Nanning, Guangxi 530022, China Abstract Secondary kill of the German cockroach, Blattella of four cockroach gel baits against various developmental stages of a laboratory (Jwax) and a field (Dorie

Wang, Changlu

265

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

266

Rickettsia associated with male-killing in a buprestid beetle  

E-print Network

bacterium that causes male-killing in an unrelated ladybird beetle species. Low levels of parthenogenesisRickettsia associated with male-killing in a buprestid beetle EILLEEN T. LAWSON , TIMOTHY A populations of the buprestid leaf-mining beetle, Brachys tessellatus, from central South Carolina, USA, show

Werren, John H.

267

The effect of road kills on amphibian populations  

Microsoft Academic Search

The diurnal movement patterns of Triturus vulgaris, Triturus cristatus, Pelobates fuscus, Bufo bufo, Rana temporaria, and Rana arvalis were investigated during five breeding seasons (1994–1998). Two main questions were addressed: (1) What is the probability of an individual amphibian getting killed when crossing the road? and (2) What fraction of the amphibian populations gets killed by traffic? The rate of

Tove Hels; Erik Buchwald

2001-01-01

268

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

269

Infant Killing and Cannibalism in Free-Living Chimpanzees  

Microsoft Academic Search

Male chimpanzees at the Gombe National Park were twice seen to attack ‘stranger’ females and seize their infants. One infant was then killed and partially eaten: the other was ‘rescued’ and carried by three different males. Once several males were found eating a freshly killed ‘stranger’ infant. A similar event was observed in Uganda by Dr. Suzuki, and Dr. Nishida

Jane Goodall

1977-01-01

270

Microorganisms and Calcium Oxalate Stone Disease  

Microsoft Academic Search

Microorganisms may have a role in the pathogenesis and prevention of kidney stones. The subjects of this review include nanobacteria, Oxalobacter formigenes, and lactic acid bacteria. Not reviewed here is the well-described role of infections of the urinary tract with Proteus species and other urease-producing organisms associated with struvite stone formation. Nanobacteria have been proposed to be very small (0.08–0.5

David S. Goldfarb

2004-01-01

271

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

272

Mass Spectrometer for Airborne Micro-Organisms  

NASA Technical Reports Server (NTRS)

Bacteria and other micro-organisms identified continously with aid of new technique for producing samples for mass spectrometer. Technique generates aerosol of organisms and feeds to spectrometer. Given species of organism produces characteristic set of peaks in mass spectrum and thereby identified. Technique useful for monitoring bacterial makeup in environmental studies and in places where cleanliness is essential, such as hospital operating rooms, breweries, and pharmaceutical plants.

Sinha, M. P.; Friedlander, S. K.

1986-01-01

273

Control of microorganisms in flowing nutrient solutions  

NASA Astrophysics Data System (ADS)

Controlling microorganisms in flowing nutrient solutions involves different techniques when targeting the nutrient solution, hardware surfaces in contact with the solution, or the active root zone. This review presents basic principles and applications of a number of treatment techniques, including disinfection by chemicals, ultrafiltration, ultrasonics, and heat treatment, with emphasis on UV irradiation and ozone treatment. Procedures for control of specific pathogens by nutrient solution conditioning also are reviewed.

Evans, R. D.

1994-11-01

274

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

PubMed

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

Rauschert, Emily Sofia Jalics; Shea, Katriona

2012-07-01

275

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

SciTech Connect

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

Carte, Jason; Wang, Ruiying; Li, Hong; Terns, Rebecca M.; Terns, Michael P. (FSU); (Georgia)

2010-11-09

276

Functional equivalence, competitive hierarchy and facilitation determine species coexistence in highly invaded grasslands.  

PubMed

Alien and native plant species often differ in functional traits. Trait differences could lead to niche differences that minimize competitive interactions and stabilize coexistence. However, trait differences could also translate into average fitness differences, leading to a competitive hierarchy that prevents coexistence. We tested whether trait differences between alien and native species translated into average fitness or stabilizing niche differences, and whether competition could explain observed coexistence within invaded grassland communities (New Zealand). Trait differences reflected marked competitive hierarchy, suggesting average fitness differences. Species coexistence was determined by a trade-off between species susceptibility to herbivory vs competitive hierarchy and facilitation. Importantly, although aliens and natives differed in their trait values, they did not differ in their competitive response, highlighting the importance of equalizing mechanisms in structuring invaded communities. Only a few alien species with a particular set of traits were able to jeopardize species coexistence when grazing was ceased. Our study explains why some alien species coexist with natives, whereas others have strong impacts on native communities. It highlights that trait differences can underlie several coexistence processes and that the demonstration of trait differences between aliens and natives is only a first step to understanding the role of biotic interactions in structuring invaded communities. PMID:25388949

Gross, Nicolas; Liancourt, Pierre; Butters, Robyn; Duncan, Richard P; Hulme, Philip E

2014-11-11

277

Biomining: metal recovery from ores with microorganisms.  

PubMed

Biomining is an increasingly applied biotechnological procedure for processing of ores in the mining industry (biohydrometallurgy). Nowadays the production of copper from low-grade ores is the most important industrial application and a significant part of world copper production already originates from heap or dump/stockpile bioleaching. Conceptual differences exist between the industrial processes of bioleaching and biooxidation. Bioleaching is a conversion of an insoluble valuable metal into a soluble form by means of microorganisms. In biooxidation, on the other hand, gold is predominantly unlocked from refractory ores in large-scale stirred-tank biooxidation arrangements for further processing steps. In addition to copper and gold production, biomining is also used to produce cobalt, nickel, zinc, and uranium. Up to now, biomining has merely been used as a procedure in the processing of sulfide ores and uranium ore, but laboratory and pilot procedures already exist for the processing of silicate and oxide ores (e.g., laterites), for leaching of processing residues or mine waste dumps (mine tailings), as well as for the extraction of metals from industrial residues and waste (recycling). This chapter estimates the world production of copper, gold, and other metals by means of biomining and chemical leaching (bio-/hydrometallurgy) compared with metal production by pyrometallurgical procedures, and describes new developments in biomining. In addition, an overview is given about metal sulfide oxidizing microorganisms, fundamentals of biomining including bioleaching mechanisms and interface processes, as well as anaerobic bioleaching and bioleaching with heterotrophic microorganisms. PMID:23793914

Schippers, Axel; Hedrich, Sabrina; Vasters, Jürgen; Drobe, Malte; Sand, Wolfgang; Willscher, Sabine

2014-01-01

278

Fibrinogenolytic and fibrinolytic activity in oral microorganisms.  

PubMed Central

Samples were taken from blood accumulated in dental alveoli after surgical removal of mandibular third molars, from subgingival plaque of teeth with advanced periodontal destructions, from teeth with infected necrotic pulps, and from subjects suffering from angular cheilitis. Of the microorganisms subcultured from these samples, 116 strains were assayed for enzymes degrading fibrinogen and fibrin. Enzymes degrading fibrinogen were assayed with the thin-layer enzyme assay cultivation technique. This assay involves the cultivation of microorganisms on culture agars applied over fibrinogen-coated polystyrene surfaces. Enzymes degrading fibrin were assayed with both a plate assay and a tube assay, in which fibrin was mixed with a microbial culture medium. Microorganisms degrading fibrinogen or fibrin or both were isolated from all sampling sites. Activity was mainly detected in strains of Actinomyces, Bacteroides, Fusobacterium, Peptococcus, Propionibacterium, and Staphylococcus aureus. Most Fusobacterium strains degraded fibrinogen only. Enzymes degrading fibrinogen as well as enzymes degrading fibrin via activation of plasminogen were revealed in strains of Clostridium, S. aureus, and Streptococcus pyogenes. It was generally found that fibrinogen was degraded by more strains than was fibrin, which indicates that different proteases may be involved. PMID:6345573

Wikström, M B; Dahlén, G; Linde, A

1983-01-01

279

Prokaryotic silicon utilizing microorganisms in the biosphere  

NASA Astrophysics Data System (ADS)

Although a little study has been done to determine the silicon utilizing prokaryotes, our previous experiments indicated that almost all Gram-positive bacteria are silicon utilizing; one of them, Streptococci survived exposure on the lunar surface for a long period in experiment done by others. Our initial experiments with these Gram positive microorganisms showed that there were limited growths of these microorganisms on carbon free silicate medium probably with the help of some carry over carbon and nitrogen during cultivation procedures. However, increase in growth rate after repeated subcultures could not be explained at present. The main groups of prokaryotes which were found silicon utilizing microorganisms were Mycobacterium, Bacillus, Nocardia, Streptomyces, Staphylococcus, Streptococcus, Lactobacillus, and Clostridium. In a another previous study by us when silicon level was studied in such grown up cells on carbon "free" silicate medium by electron prove microanalyser, it was found that silicon in cells grown on carbon "free" silicate medium was much higher (24.9%) than those grown on conventional carbon based medium (0.84%). However, these initial findings are encouraging for our future application of this group of organisms on extraterrestrial surfaces for artificial micro-ecosystem formation. It was found that when electropositive elements are less in extraterrestrial situation, then polymerization of silicon-oxygen profusion may occur easily, particularly in carbon and nitrogen paucity in the rocky worlds of the Universe.

Gupta, D.; Das, S.

2012-12-01

280

Cooperative self-organization of microorganisms  

NASA Astrophysics Data System (ADS)

In nature, microorganisms must often cope with hostile environmental conditions. To do so they have developed sophisticated cooperative behaviour and intricate communication capabilities, such as: direct cell-cell physical interactions via extra-membrane polymers, collective production of extracellular 'wetting' fluid for movement on hard surfaces, long range chemical signalling such as quorum sensing and chemotactic (bias of movement according to gradient of chemical agent) signalling, collective activation and deactivation of genes and even exchange of genetic material. Utilizing these capabilities, the colonies develop complex spatio-temporal patterns in response to adverse growth conditions. We present a wealth of beautiful patterns formed during colony development of various microorganisms and for different environmental conditions. Invoking ideas from pattern formation in non-living systems and using 'generic' modelling we are able to reveal novel survival strategies which account for the salient features of the evolved patterns. Using the models, we demonstrate how communication leads to self-organization via cooperative behaviour of the cells. In this regard, pattern formation in microorganisms can be viewed as the result of the exchange of information between the micro-level (the individual cells) and the macro-level (the colony). As such, a full understanding of bacterial behaviour must focus simultaneously on individual cell responses and overall colony organization.

Ben-Jacob, Eshel; Cohen, Inon; Levine, Herbert

2000-06-01

281

Food fermentations: microorganisms with technological beneficial use.  

PubMed

Microbial food cultures have directly or indirectly come under various regulatory frameworks in the course of the last decades. Several of those regulatory frameworks put emphasis on "the history of use", "traditional food", or "general recognition of safety". Authoritative lists of microorganisms with a documented use in food have therefore come into high demand. One such list was published in 2002 as a result of a joint project between the International Dairy Federation (IDF) and the European Food and Feed Cultures Association (EFFCA). The "2002 IDF inventory" has become a de facto reference for food cultures in practical use. However, as the focus mainly was on commercially available dairy cultures, there was an unmet need for a list with a wider scope. We present an updated inventory of microorganisms used in food fermentations covering a wide range of food matrices (dairy, meat, fish, vegetables, legumes, cereals, beverages, and vinegar). We have also reviewed and updated the taxonomy of the microorganisms used in food fermentations in order to bring the taxonomy in agreement with the current standing in nomenclature. PMID:22257932

Bourdichon, François; Casaregola, Serge; Farrokh, Choreh; Frisvad, Jens C; Gerds, Monica L; Hammes, Walter P; Harnett, James; Huys, Geert; Laulund, Svend; Ouwehand, Arthur; Powell, Ian B; Prajapati, Jashbhai B; Seto, Yasuyuki; Ter Schure, Eelko; Van Boven, Aart; Vankerckhoven, Vanessa; Zgoda, Annabelle; Tuijtelaars, Sandra; Hansen, Egon Bech

2012-03-15

282

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

283

Protein languages differ depending on microorganism lifestyle.  

PubMed

Few quantitative measures of genome architecture or organization exist to support assumptions of differences between microorganisms that are broadly defined as being free-living or pathogenic. General principles about complete proteomes exist for codon usage, amino acid biases and essential or core genes. Genome-wide shifts in amino acid usage between free-living and pathogenic microorganisms result in fundamental differences in the complexity of their respective proteomes that are size and gene content independent. These differences are evident across broad phylogenetic groups-a result of environmental factors and population genetic forces rather than phylogenetic distance. A novel comparative analysis of amino acid usage-utilizing linguistic analyses of word frequency in language and text-identified a global pattern of higher peptide word repetition in 376 free-living versus 421 pathogen genomes across broad ranges of genome size, G+C content and phylogenetic ancestry. This imprint of repetitive word usage indicates free-living microorganisms have a bias for repetitive sequence usage compared to pathogens. These findings quantify fundamental differences in microbial genomes relative to life-history function. PMID:24828817

Grzymski, Joseph J; Marsh, Adam G

2014-01-01

284

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.

285

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

286

A New Fluorescence Staining Assay for Visualizing Living Microorganisms in Soil  

PubMed Central

5- (and 6-)Sulfofluorescein diacetate (SFDA), which is converted to a fluorescent product by intracellular esterase activity, was used to stain living microorganisms, including bacteria, Saccharomyces cerevisiae, and fungi, in soil. SFDA (1 mM) dissolved in ethyl alcohol was added to an intact soil sample, and the preparation was examined with an epifluorescence microscope. Bright single cells and colonies of live bacteria were observed without interference from the autofluorescence of soil minerals and detritus. Cultured Escherichia coli was killed through heat treatment; thus, SFDA was concluded to stain only living cells. Microbial colonies obtained from natural soils and various cultured strains were tested. It was found that 151 of 154 colonies from natural soils were stained and that hyphae and spores from 1 of 28 cultured microbial strains were not stained. The SFDA method was successfully used to visualize and count bacteria in soil samples from Mount Shiga in Japan. PMID:16535127

Tsuji, T.; Kawasaki, Y.; Takeshima, S.; Sekiya, T.; Tanaka, S.

1995-01-01

287

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

288

Hydrilla verticillata (Hydrocharitaceae), a recent invader threatening Brazil’s freshwater environments: a review of the extent of the problem  

Microsoft Academic Search

Hydrilla verticillata (Hydrocharitaceae) is a highly prolific, rooted submerged macrophyte native to Asia that has invaded aquatic systems worldwide,\\u000a causing many ecological and human-related problems. Hydrilla recently invaded the Paraná River basin in Brazil, making other ecologically and socially important Brazilian watersheds\\u000a more susceptible to invasion by this plant. Here, I summarize the relevant information about Hydrilla, focusing on its

W. T. Z. Sousa

2011-01-01

289

Protein chlorination in neutrophil phagosomes and correlation with bacterial killing.  

PubMed

Neutrophils ingest and kill bacteria within phagocytic vacuoles. We investigated where they produce hypochlorous acid (HOCl) following phagocytosis by measuring conversion of protein tyrosine residues to 3-chlorotyrosine. We also examined how varying chloride availability affects the relationship between HOCl formation in the phagosome and bacterial killing. Phagosomal proteins, isolated following ingestion of opsonized magnetic beads, contained 11.4 Cl-Tyr per thousand tyrosine residues. This was 12 times higher than the level in proteins from the rest of the neutrophil and ~6 times higher than previously recorded for protein from ingested bacteria. These results indicate that HOCl production is largely localized to the phagosomes and a substantial proportion reacts with phagosomal protein before reaching the microbe. This will in part detoxify the oxidant but should also form chloramines which could contribute to the killing mechanism. Neutrophils were either suspended in chloride-free gluconate buffer or pretreated with formyl-Met-Leu-Phe, a procedure that has been reported to deplete intracellular chloride. These treatments, alone or in combination, decreased both chlorination in phagosomes and killing of Staphylococcus aureus by up to 50%. There was a strong positive correlation between the two effects. Killing was predominantly oxidant and myeloperoxidase dependent (88% inhibition by diphenylene iodonium and 78% by azide). These results imply that lowering the chloride concentration limits HOCl production and oxidative killing. They support a role for HOCl generation, rather than an alternative myeloperoxidase activity, in the killing process. PMID:25236747

Green, Jessie N; Kettle, Anthony J; Winterbourn, Christine C

2014-12-01

290

Safe Micro-organism: Micro-organisms for Investigations in Schools and Colleges  

NSDL National Science Digital Library

This 6-page online safety form lists microorganisms that are considered suitable for use in schools and colleges. It includes a table that describes selected bacteria and fungi which present minimum risk given good practice. Fields of the table include microbe name, educational use/interest/suitability, and ease of use/maintenance. The document also addresses the use of viruses, algae protozoa (including slime molds), and lichens in the classroom. A group of microorganisms that were previously suggested for use in schools but are no longer considered suitable are also listed.

Society for General Microbiology (SGM)

291

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

292

Generalized killing equations and symmetries of spinning space  

NASA Astrophysics Data System (ADS)

A set of general conditions for the isometrics of d-dimensional spinning space is derived. These equations constitute a Grassmann valued extension of the Killing equations for ordinary space. They are developed as invariances of spinning particle actions. Solutions for extended Killing equations in arbitrary curved space are presented. The spinning particles in d-dimensions are shown to possess new types of supersymmetries which transform the commuting and anti-commuting coordinates linearly and nonlinearly. The algebra of these nonlinear transformations is presented. A complete solution of the generalized Killing equations is outlined. An infinite set of conserved charges is constructed.

Rietdijk, R. H.; Vanholten, J. W.

1989-04-01

293

Special Killing forms on toric Sasaki–Einstein manifolds  

NASA Astrophysics Data System (ADS)

In this paper we study the interplay between complex coordinates on the Calabi–Yau metric cone and the special Killing forms on the toric Sasaki–Einstein manifold. First, we give a procedure to locally construct the special Killing forms. Finally, we exemplify the general scheme in the case of the five-dimensional {{Y}p,q} spaces, identifying the additional special Killing 2-forms which were previously obtained using a different method by Visinescu (2012 Mod. Phys. Lett. A 27 1250217).

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

2014-12-01

294

HIV transcription is induced with some forms of cell killing  

SciTech Connect

Using HeLa cells stably transfected with an HIV-LTR-CAT construct`, we demonstrated a peak in CAT induction that occurs in viable (but not necessarily cell-division-competent) cells 24 h following exposure to some cell-killing agents. {Gamma} rays were the only cell-killing agent which did not induce HIV transcription; this can be attributed to the fact that {gamma}-ray-induced apoptotic death requires function p53, which is missing in HeLa cells. For all other agents, HIV-LTR induction was dose-dependent and correlated with the amount of cell killing that occurred in the culture.

Woloschak, G.E. [Argonne National Lab., IL (United States); Schreck, S. [Argonne National Lab., IL (United States)][South Carolina Univ., Columbia, SC (United States). Dept. of Chemistry; Panozzo, J. [Loyola Univ. Medical Center, Maywood, IL (United States); Chang-Liu, C.-M. [Argonne National Lab., IL (United States); Libertin, C.R. [Loyola Univ. Medical Center, Maywood, IL (United States)

1996-11-01

295

Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens  

SciTech Connect

The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

Daniel P. Molloy

2004-02-24

296

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

297

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

298

Biocatalysis and biotransformation of resveratrol in microorganisms.  

PubMed

Resveratrol, a major stilbene phytoalexin, is a valuable polyphenol that has been recognized for its benefits to human health. Resveratrol has antioxidant and antitumor effects and promotes longevity. It is used in medicine, health care products, cosmetics, and other industries. Therefore, a sustainable source for resveratrol production is required. This review describes the metabolic engineering of microorganisms, the biotransformation and biosynthesis of endophytes and the oxidation or degradation of resveratrol. We compare various available methods for resveratrol production, and summarize the practical challenges facing the microbial production of resveratrol. The future research direction for resveratrol is also discussed. PMID:25179823

Mei, Yan-Zhen; Liu, Ruo-Xue; Wang, Dong-Peng; Wang, Xia; Dai, Chuan-Chao

2015-01-01

299

Propulsion of Microorganisms by Surface Distortions  

NASA Astrophysics Data System (ADS)

Swimming strategies of microorganisms must conform to the principles of self-propulsion at low Reynolds numbers. Here we relate the translational and rotational speeds to the surface motions of a swimmer and, for spheres, make evident novel constraints on mechanisms for propulsion. The results are applied to a cyanobacterium, an organism whose motile mechanism is unknown, by considering incompressible streaming of the cell surface and oscillatory, tangential surface deformations. Finally, swimming efficiency using tangential motions is related to the surface velocities and a bound on the efficiency is obtained.

Stone, Howard A.; Samuel, Aravinthan D. T.

1996-11-01

300

Microorganisms within Human Follicular Fluid: Effects on IVF  

PubMed Central

Our previous study reported microorganisms in human follicular fluid. The objective of this study was to test human follicular fluid for the presence of microorganisms and to correlate these findings with the in vitro fertilization (IVF) outcomes. In this study, 263 paired follicular fluids and vaginal swabs were collected from women undergoing IVF cycles, with various causes for infertility, and were cultured to detect microorganisms. The cause of infertility and the IVF outcomes for each woman were correlated with the microorganisms detected within follicular fluid collected at the time of trans-vaginal oocyte retrieval. Microorganisms isolated from follicular fluids were classified as: (1) ‘colonizers’ if microorganisms were detected within the follicular fluid, but not within the vaginal swab (at the time of oocyte retrieval); or (2) ‘contaminants’ if microorganisms detected in the vagina at the time of oocyte retrieval were also detected within the follicular fluid. The presence of Lactobacillus spp. in ovarian follicular fluids was associated with embryo maturation and transfer. This study revealed microorganisms in follicular fluid itself and that the presence of particular microorganisms has an adverse affect on IVF outcomes as seen by an overall decrease in embryo transfer rates and pregnancy rates in both fertile and infertile women, and live birth rates in women with idiopathic infertility. Follicular fluid microorganisms are a potential cause of adverse pregnancy outcomes in IVF in both infertile women and in fertile women with infertile male partners. PMID:23554970

Pelzer, Elise S.; Allan, John A.; Waterhouse, Mary A.; Ross, Tara; Beagley, Kenneth W.; Knox, Christine L.

2013-01-01

301

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

PubMed

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

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

2015-02-01

302

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

PubMed Central

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

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

2015-01-01

303

On the Lie subalgebra of Killing-Milne and Killing-Cartan vector fields in Newtonian space-time  

E-print Network

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

Chamel, N

2014-01-01

304

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

305

'Pseudotumour' invading the proximal femur with normal metal ions following metal on metal hip resurfacing.  

PubMed

A 75-year-old woman who had undergone hybrid metal-on-metal hip resurfacing 8?years earlier underwent revision arthroplasty because of hip, groin and lateral thigh pain. The main differential was aseptic loosening; however, serum cobalt and chromium levels were normal. Multiple imaging modalities revealed a periprosthetic, cystic soft tissue mass adjacent to the proximal femur. A large 'pseudotumour' with proximal femoral invasion was found at revision arthroplasty. We report the first finding of a 'pseudotumour' invading the proximal femur with normal metal ions following metal on metal hip resurfacing. PMID:25670783

Krishnan, Harry; Sugand, Kapil; Ali, Ibrahim; Smith, Jay

2015-01-01

306

Temporary extravascular shunt for reconstruction of a superior vena cava invaded by a lung tumor.  

PubMed

Advanced central lung cancers can invade the superior vena cava (SVC). Although the indications for resection of the vessel remain controversial, it has been suggested that it increases the long-term survival of selected patients; however, little consensus has been reached regarding the optimal method of vascular reconstruction. While the SVC is often replaced during unprotected cross-clamp, the placement of a temporary venous shunt with a view to preserve the periprocedural safety and facilitate the postoperative management seems preferable. We describe an SVC reconstruction procedure using an autologous pericardial patch and placement of a temporary extravascular shunt via a lateral thoracotomy. PMID:25468109

Yotsukura, Masaya; Kinoshita, Tomonari; Kamiyama, Ikuo; Hato, Tai; Goto, Taichiro; Ohtsuka, Takashi; Yoshitake, Akihiro; Kudo, Mikihiko; Kohno, Mitsutomo

2014-12-01

307

Bioremediation of trinitrotolulene by a ruminal microorganism  

SciTech Connect

2,4,6-trinitrotoluene (TNT) has been widely used for the production of explosives because of its low boiling point, high stability, low impact sensitivity, and safe manufacture. More than 1,100 military facilities, each potentially contaminated with munitions waste, are expected to require treatment of more than one million cubic yards of contaminated soils. The cost associated with remediation of these sites has been estimated to be in excess of $1.5 billion. Recently, researchers have studied ruminal microorganisms in relation to their ability to degrade xenobiotic compounds. Many of these organisms are strict anaerobes with optimal redox potentials as low as -420 mV. Ruminal organisms have been shown capable of destroying some pesticides, such as parathion, p-nitrophenol, and biphenyl-type compounds; thiono isomers, and nitrogen-containing heterocyclic plant toxins such as the pyrrolizidine alkaloids. Many of these compounds have structures similar to TNT. A TNT-degrading ruminal microorganism has been isolated from goat rumen fluid with successive enrichments on triaminotoluene (TAT) and TNT. The isolate, designated G.8, utilizes nitrate and lactate as the primary energy source. G.8 was able to tolerate and metabolite levels of TNT up to the saturation point of 125 mg/l.

Lee, Taejin; Williamson, K.J.; Craig, A.M. [Oregon State Univ., Corvallis, OR (United States)

1995-10-01

308

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

309

Microorganisms resistant to free-living amoebae.  

PubMed

Free-living amoebae feed on bacteria, fungi, and algae. However, some microorganisms have evolved to become resistant to these protists. These amoeba-resistant microorganisms include established pathogens, such as Cryptococcus neoformans, Legionella spp., Chlamydophila pneumoniae, Mycobacterium avium, Listeria monocytogenes, Pseudomonas aeruginosa, and Francisella tularensis, and emerging pathogens, such as Bosea spp., Simkania negevensis, Parachlamydia acanthamoebae, and Legionella-like amoebal pathogens. Some of these amoeba-resistant bacteria (ARB) are lytic for their amoebal host, while others are considered endosymbionts, since a stable host-parasite ratio is maintained. Free-living amoebae represent an important reservoir of ARB and may, while encysted, protect the internalized bacteria from chlorine and other biocides. Free-living amoebae may act as a Trojan horse, bringing hidden ARB within the human "Troy," and may produce vesicles filled with ARB, increasing their transmission potential. Free-living amoebae may also play a role in the selection of virulence traits and in adaptation to survival in macrophages. Thus, intra-amoebal growth was found to enhance virulence, and similar mechanisms seem to be implicated in the survival of ARB in response to both amoebae and macrophages. Moreover, free-living amoebae represent a useful tool for the culture of some intracellular bacteria and new bacterial species that might be potential emerging pathogens. PMID:15084508

Greub, Gilbert; Raoult, Didier

2004-04-01

310

Sterilization of Microorganisms by Ozone and Ultrasound  

NASA Astrophysics Data System (ADS)

The results of recent experimental methods of sterilization of microorganisms with the use of ozone and ultrasound are presented. The main aim was to optimize the process of sterilization in water solution taking into account the ozone concentration, the power of ultrasonic emitter and the temperature of water. In the present work, the ultrasonic cavitation with simultaneous ozone generation has been used. The high ozone concentration in water solution was achieved by two-barrier glow discharge generated at atmospheric pressure and a cooling thermo-electric module. Such a sterilizer consists of ozone generator in a shape of flat electrodes covered with dielectric material and a high-voltage pulsed power supply of 250 W. The sterilization camera was equipped with ultrasonic source operated at 100 W. The experiments on the inactivation of bacteria of the Bacillus Cereus type were carried out in the distilled water saturated by ozone. The ozone concentration in the aqueous solution was 10 mg/1, whereas the ozone concentration at the output of ozone generator was 30 mg/1. The complete inactivation of spores took 15 min. Selection of the temperature of water, the ozone concentrations and ultrasonic power allowed to determine the time necessary for destroying the row of microorganisms.

Krasnyj, V. V.; Klosovskij, A. V.; Panasko, T. A.; Shvets, O. M.; Semenova, O. T.; Taran, V. S.; Tereshin, V. I.

2008-03-01

311

From chemosensing in microorganisms to practical biosensors  

NASA Astrophysics Data System (ADS)

Microorganisms like bacteria can sense concentrations of chemoattractants in their medium very accurately. They achieve this through interaction between the receptors on their cell surfaces and chemoattractant molecules (like sugar). Physical processes like diffusion set some limits on the accuracy of detection, which was discussed by Berg and Purcell in the late seventies. We re-examine their work in order to assess what insight it may offer for 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 and unbinding reactions between the chemoattractants and the receptors. Then we compute the binding flux for this system, which Berg and Purcell had discussed. 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.

Ghosh, Surya K.; Kundu, Tapanendu; Sain, Anirban

2012-11-01

312

The role of microorganisms in atopic dermatitis  

PubMed Central

Atopic dermatitis (AD) is a common, fluctuating skin disease that is often associated with atopic conditions such as asthma and IgE-mediated food allergy and whose skin lesions are characterized by a Th-2 cell-mediated response to environmental antigens. The increasing prevalence and severity of atopic diseases including AD over the last three decades has been attributed to decreased exposure to microorganisms during early life, which may result in an altered Th-1/Th-2-balance and/or reduced T cell regulation of the immune response. Patients with AD exhibit defects in innate and acquired immune responses resulting in a heightened susceptibility to bacterial, fungal and viral infections, most notably colonization by S. aureus. Toxins produced by S. aureus exacerbate disease activity by both the induction of toxin-specific IgE and the activation of various cell types including Th-2 cells, eosinophils and keratinocytes. Allergens expressed by the yeast Malazessia furfur, a component of normal skin flora, have also been implicated in disease pathogenesis in a subset of AD patients. Microorganisms play an influential role in AD pathogenesis, interacting with disease susceptibility genes to cause initiation and/or exacerbation of disease activity. PMID:16542358

Baker, B S

2006-01-01

313

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

314

PLANT–SOIL–MICROORGANISM INTERACTIONS: HERITABLE RELATIONSHIP BETWEEN PLANT GENOTYPE AND ASSOCIATED SOIL MICROORGANISMS  

Microsoft Academic Search

Although soil microbial communities are known to play crucial roles in the cycling of nutrients in forest ecosystems and can vary by plant species, how microorganisms respond to the subtle gradients of plant genetic variation is just beginning to be appreciated. Using a model Populus system in a common garden with replicated clones of known genotypes, we evaluated microbial biomass

Jennifer A. Schweitzer; Joseph K. Bailey; Dylan G. Fischer; Carri J. LeRoy; Eric V. Lonsdorf; Thomas G. Whitham; Stephen C. Hart

2008-01-01

315

NK cells kill mycobacteria directly by releasing perforin and granulysin.  

PubMed

Although the mechanisms underlying the cytotoxic effect of NK cells on tumor cells and intracellular bacteria have been studied extensively, it remains unclear how these cells kill extracellular bacterial pathogens. In this study, we examine how human NK cells kill Mycobacterium kansasii and M.tb. The underlying mechanism is contact dependent and requires two cytolytic proteins: perforin and granulysin. Mycobacteria induce enhanced expression of the cytolytic proteins via activation of the NKG2D/NCR cell-surface receptors and intracellular signaling pathways involving ERK, JNK, and p38 MAPKs. These results suggest that NK cells use similar cellular mechanisms to kill both bacterial pathogens and target host cells. This report reveals a novel role for NK cells, perforin, and granulysin in killing mycobacteria and highlights a potential alternative defense mechanism that the immune system can use against mycobacterial infection. PMID:25139289

Lu, Chia-Chen; Wu, Ting-Shu; Hsu, Ya-Jing; Chang, Chih-Jung; Lin, Chuan-Sheng; Chia, Ju-Hsin; Wu, Tsu-Lan; Huang, Tsung-Teng; Martel, Jan; Ojcius, David M; Young, John D; Lai, Hsin-Chih

2014-12-01

316

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.

317

Alcohol Poisoning Kills 6 Americans Every Day, CDC Says  

MedlinePLUS

... enable JavaScript. Alcohol Poisoning Kills 6 Americans Every Day, CDC Says Older adults hardest hit by binge- ... six people die in the United States each day after consuming far too much alcohol in too ...

318

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...

319

Drought and Beetle-Killed Piñon Pines in Arizona  

USGS Multimedia Gallery

Drought and beetle-killed piñon pines in Walnut Canyon National Monument near Flagstaff, Arizona, amid some surviving trees. Forest drought stress is highly correlated with mortality from poor growth, bark beetle outbreaks, and high-severity fire....

320

Drought and Beetle-Killed Piñon Pines in Arizona  

USGS Multimedia Gallery

Drought and beetle-killed piñon pines in Walnut Canyon National Monument near Flagstaff, Arizona, amid a few surviving trees. Forest drought stress is strongly correlated with tree mortality from poor growth, bark beetle outbreaks, and high-severity fire....

321

Exobiology and the effect of physical factors on micro-organisms.  

PubMed

A study of the action of different physical factors on micro-organisms is necessary for a further development of exobiology. The action of temperature on crystalline preparations of catalase and peroxidase was studied by means of oscillographic polarography. A determination of the height of polarographic waves at the decrease of temperature from 20 degrees C to 0 degrees C has shown that structural elements of the peroxidase molecule connected with the enzymatic activity are more stable with the decrease of temperature cf. catalase. A relative resistance of the dehydrogenase activity in Az. vinelandii cells to high vacuum was found. Incubation of azotobacter cells under vacuum of 10(-9) mm Hg during 72 hr did not decrease the activity of alcohol and succinic dehydrogenase. Bac. cereus spores can be preserved from bactericidal UV action by thin films of chrome. The thickness of chrome film being 200-670 angstroms, spores are killed by a dose of 7.8 x 10(7) erg/cm2 at 253.7 microns wave length. Spores covered by chrome film thicker than 800 angstroms remain alive after this treatment. Investigations carried out with an 'Artificial Mars' camera led to the following results. The growth of Bac. megaterium on liquid growth media in this camera ceases as a result of UV rays killing all cells after 3 weeks. Untreated bacteria grow in the camera for a long time. Spore-forming bacteria isolated from the sand of the Kara-Kum Desert grow in ground limonite (with the addition of 2% garden soil) having maximum hygroscopic humidity (3.8%). Freezing and thawing (from -60 degrees C to +25 degrees C) corresponding to day temperature deviations on Mars, low pressure (P=10 mm Hg) and the composition of the atmosphere (CO2-50%, N2-40%, Ar-10%) do not influence the growth of xerophylic bacteria under study. Humidity is the main factor limiting the growth of micro-organisms under 'Artificial Mars' conditions. According to the further development of the microbiological meteorite analysis methods, samples of rocks and stone meteorites were sterilized, incubated in the desert or on a snow surface in the Arctic and after different times (from 100 days to 7 months), investigated. In all cases, microbes were found only on the sample surfaces, whereas 1 cm from the surface and in the central parts micro-organism were completely absent. Hence, microbiological analysis of central parts of meteorites fallen in the Arctic or during dry periods of the year in the desert can give reliable results. PMID:11973848

Imshenetsky, A A; Abyzov, S S; Voronov, G T; Kuzjurina, L A; Lysenko, S V; Sotnikov, G G; Fedorova, R I

1967-01-01

322

1. GENERAL VIEW OF HOG KILLING ROOM ON LEVEL 4; ...  

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

1. GENERAL VIEW OF HOG KILLING ROOM ON LEVEL 4; LOOKING NORTHWEST; A PORTION OF THE SCALDING TANK IS VISIBLE AT EXTREME RIGHT, CENTER; CONCRETE PYLONS AT LOWER RIGHT SUPPORTED BY SCRAPING MACHINE; FINAL SCRAPING WAS DONE BY WORKERS STANDING ON ELEVATED PLATFORMS AT LEFT; BATHTUB-SHAPED CART NEAR CENTER OF PHOTO WAS USED TO TRANSPORT OFFAL TO RENDERING AREAS - Rath Packing Company, Hog Killing Building, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

323

[Field report from large-scale killing of ducks].  

PubMed

An outbreak of avian influenza in August 2007 resulted in the culling of hundreds of thousands of Peking ducks. An earlier tutorial had shown that whole house gassing with carbon dioxide to kill waterfowl has to be refused because of interference with animal welfare. Culling by electrocution is a reliable method that fulfils animal welfare requirements. Stationary electrocution lines for slaughtering should be preferred if suitable for the killing of the birds. Mobile electrocution lines (MET) are a good alternative or supplementation with a capacity of circa 2,500 animals per hour. MET are suitable for killing Peking ducks with a weight of approximately 500 g. At least two veterinarians are required per MET for the supervision of animal welfare during culling. When following German animal welfare laws, killing in mobile gas containers filled with carbon dioxide is an alternative with a capacity comparable to that of MET. The problem of looking into the containers for controlled stunning and killing can be solved by installing observation windows. Manpower requirements are comparable to those of MET, while requirements for material and transportation are unlikely higher. This method is suitable for birds which are too small to be killed by electrocution. PMID:18500150

Scheibl, P

2008-04-01

324

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

325

Microorganic compounds associated with sediments in the Humber rivers  

Microsoft Academic Search

The study investigates pollution by micro-organic contaminants in riverine systems in NE England with the following four key objectives: (1) to establish the range and concentrations of micro-organic compounds in relation to land use; (2) investigate how the type and concentrations of micro-organics can vary seasonally; (3) compare bed-sediment and suspended-sediment concentrations, and to (4) assess the use of `whole-water'

Juliet L. A Long; William A House; Andrew Parker; Joy E Rae

1998-01-01

326

COMPOSTING: STABILIZATION, DEWATERING, VOLUME REDUCTION, AND PATHOGEN KILL  

Technology Transfer Automated Retrieval System (TEKTRAN)

Aerobic composting is the biological oxidative decomposition of organic materials by successive communities of microorganisms under different temperature regimes which produces a humified end-product. Composting reduces moisture content of organic byproducts. Thermophilic temperatures attained dur...

327

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

Bu?i?, Miloš; Hulák, Martin; Kouba, Antonín

2011-01-01

328

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

329

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

PubMed Central

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

Carroll, Scott P

2011-01-01

330

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

331

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

PubMed Central

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

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

2014-01-01

332

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

333

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

334

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

PubMed

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

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

2015-02-01

335

Haemophilus ducreyi attaches to and invades human epithelial cells in vitro.  

PubMed Central

Haemophilus ducreyi is a sexually transmitted pathogen that causes genital ulcers and inguinal adenopathy. Because chancroidal ulcers are most commonly located on the foreskins of uncircumcised males, we utilized human foreskin epithelial cells (HFECs) to investigate the initial interaction of H. ducreyi with its host. The eight different strains of H. ducreyi that were studied varied in their abilities to attach to these epithelial cells, with six strains consistently attaching to > or = 90% of HFECs and two strains attaching to < 25% of HFECs. The strains with low levels of adherence also failed to exhibit chaining in broth culture and were avirulent in the rabbit model, suggesting that virulence in this model and attachment may be linked. The most adherent strain, LA228R, was further evaluated for its ability to invade HFECs and HEp-2 cells. Scanning electron microscopy and transmission electron microscopy of HFECs after interaction with LA228R produced images consistent with attachment, ingestion into vesicles, and escape from the vesicles into the cytoplasm. In addition, the gentamicin protection assay and inhibition of invasion by cytochalasin B and D indicated that LA228R was able to invade both HFECs and HEp-2 cells. Further examination of the mechanisms involved in the adherence and invasion of H. ducreyi into epithelial cells and their correlation with virulence will provide a better understanding of the pathogenesis of the disease caused by this important pathogen. Images PMID:7960145

Totten, P A; Lara, J C; Norn, D V; Stamm, W E

1994-01-01

336

Microorganisms -- Directorate for Biological Sciences (BIO), Dear Colleague Letter  

NSF Publications Database

... that BIO seeks to encourage research on microorganisms, especially prokaryotes and filamentous fungi ... habitats as diverse as farmland and marshland, plants and animals, deserts and oceans, volcanic ...

337

Analysis of Membrane Lipids of Airborne Micro-Organisms  

NASA Technical Reports Server (NTRS)

A method of characterization of airborne micro-organisms in a given location involves (1) large-volume filtration of air onto glass-fiber filters; (2) accelerated extraction of membrane lipids of the collected micro-organisms by use of pressurized hot liquid; and (3) identification and quantitation of the lipids by use of gas chromatography and mass spectrometry. This method is suitable for use in both outdoor and indoor environments; for example, it can be used to measure airborne microbial contamination in buildings ("sick-building syndrome"). The classical approach to analysis of airborne micro-organisms is based on the growth of cultureable micro-organisms and does not provide an account of viable but noncultureable micro-organisms, which typically amount to more than 90 percent of the micro-organisms present. In contrast, the present method provides an account of all micro-organisms, including cultureable, noncultureable, aerobic, and anaerobic ones. The analysis of lipids according to this method makes it possible to estimate the number of viable airborne micro-organisms present in the sampled air and to obtain a quantitative profile of the general types of micro-organisms present along with some information about their physiological statuses.

MacNaughton, Sarah

2006-01-01

338

The ecology of micro-organisms in a closed environment  

NASA Technical Reports Server (NTRS)

Microorganisms under closed environmental ecological conditions with reference to astronauts infectious diseases, discussing bacteria growth in Biosatellite 2 and earth based closed chamber experiments

Fox, L.

1971-01-01

339

Engineered microorganisms capable of producing target compounds under anaerobic conditions  

DOEpatents

The present invention is generally provides recombinant microorganisms comprising engineered metabolic pathways capable of producing C3-C5 alcohols under aerobic and anaerobic conditions. The invention further provides ketol-acid reductoisomerase enzymes which have been mutated or modified to increase their NADH-dependent activity or to switch the cofactor preference from NADPH to NADH and are expressed in the modified microorganisms. In addition, the invention provides isobutyraldehyde dehydrogenase enzymes expressed in modified microorganisms. Also provided are methods of producing beneficial metabolites under aerobic and anaerobic conditions by contacting a suitable substrate with the modified microorganisms of the present invention.

Buelter, Thomas (Denver, CO); Meinhold, Peter (Denver, CO); Feldman, Reid M. Renny (San Francisco, CA); Hawkins, Andrew C. (Parker, CO); Urano, Jun (Irvine, CA); Bastian, Sabine (Pasadena, CA); Arnold, Frances (La Canada, CA)

2012-01-17

340

Welfare of animals at slaughter and killing: a new regulation on the protection of animals at the time of killing  

Microsoft Academic Search

Recently, the European Commission (EC) has published a proposal for a Council Regulation on the protection of animals at the\\u000a time of killing. The proposed regulation will enhance the technical requirements of Directive 93\\/119\\/EC on the protection\\u000a of animals at the time of slaughter or killing, which have not been amended since 1993. The main specific problems identified\\u000a with the

Annamaria Passantino

2009-01-01

341

Early photosynthetic microorganisms and environmental evolution  

NASA Technical Reports Server (NTRS)

Microfossils which are preserved as shrivelled kerogenous residues provide little information about cellular organization and almost none about the metabolic properties of the organisms. The distinction between prokaryotic vs eukaryotic, and phototrophic vs chemo- and organotrophic fossil microorganisms rests entirely on morphological comparisons with recent counterparts. The residual nature of the microbial fossil record promotes the conclusion that it must be biased toward (a) most abundant organisms, (b) those most resistant to degradation, and (c) those inhabiting environments with high preservation potential e.g., stromatolites. These criteria support the cyanophyte identity of most Precambrian microbial fossils on the following grounds: (1) as primary producers they dominate prokaryotic communities in modern extreme environments, e.g., intertidal zone; (2) several morphological counterparts of modern cyanophytes and microbial fossils have been established based on structure, cell division patterns and degradation sequences. The impact of anaerobic and oxygenic microbial photosynthesis on the evolution of Precambrian environments is discussed.

Golubic, S.

1980-01-01

342

[Probiotics based on live cultures of microorganisms].  

PubMed

The modern state of probiotic design and production was discussed in the survey. The worldwide data concerning types of probiotics and their use for restoration of resident microflora of hot-blooded animals and people were systematized. Much attention has been recently paid to the use of the natural preparations to maintain and regenerate the state of the resident microflora of animals and people. These preparations are known as probiotics. The term "probiotic" means microorganisms or substances which are capable to render sanitary effect on macroorganism. I. I. Mechnikov's concept on detoxifications of harmful substances formed in the digestive tract of men by probiotics is expounded. The modern concepts of the probiotics division into groups have been presented. Different kinds of industrial probiotics were considered. The mechanism of positive action of probiotics and their mutual relations with micro- and macroorganisms were provided. The scientific substantiation of new probiotic design was presented. PMID:12436872

Smirnov, V V; Kovalenko, N K; Podgorski?, V S; Sorokulova, I B

2002-01-01

343

Adsorption of Sr by immobilized microorganisms  

SciTech Connect

Wastewaters from numerous industrial and laboratory operations can contain toxic or undesirable components such as metal ions, which must be removed before discharge to surface waters. Adsorption processes that have high removal efficiencies are attractive methods for removing such contaminants. For economic operations, it is desirable to have an adsorbent that is selective for the metal contaminant of interest, has high capacity for the contaminant, has rapid adsorption kinetics, can be economically produced, and can be regenerated to a concentrated waste product or decomposed to a low-volume waste. Selected microorganisms are potentially useful adsorbents for these applications because they can be inexpensive, have high selectivities, and have high capacities for adsorption of many heavy metals, which are often problems in a variety of industries. A laboratory-scale packed column containing microbial cells immobilized within a gelatin matrix has been prepared, and its application to removal of Sr from a simulated wastewater is described. 6 refs., 2 figs., 3 tabs.

Watson, J.S.; Scott, C.D.; Faison, B.D.

1988-01-01

344

POLYPEPTIDE AND POLYSACCHARIDE PROCESSING IN HYPERTHERMOPHILIC MICROORGANISMS  

SciTech Connect

This project focused on the microbial physiology and biochemistry of heterotrophic hyperthermophiles with respect to mechanisms by which these organisms process polypeptides and polysaccharides under normal and stressed conditions. Emphasis is on two model organisms, for which completed genome sequences are available: Pyrococcus furiosus (growth Topt of 98°C), an archaeon, and Thermotoga maritima (growth Topt of 80°C), a bacterium. Both organisms are obligately anaerobic heterotrophs that reduce sulfur facultatively. Whole genome cDNA spotted microarrays were used to follow transcriptional response to a variety of environmental conditions in order to identify genes encoding proteins involved in the acquisition, synthesis, processing and utilization of polypeptides and polysaccharides. This project provided new insights into the physiological aspects of hyperthermophiles as these relate to microbial biochemistry and biological function in high temperature habitats. The capacity of these microorganisms to produce biohydrogen from renewable feedstocks makes them important for future efforts to develop biofuels.

KELLY, ROBERT M.

2008-12-22

345

Light-energy conversion in engineered microorganisms.  

PubMed

Increasing interest in renewable resources by the energy and chemical industries has spurred new technologies both to capture solar energy and to develop biologically derived chemical feedstocks and fuels. Advances in molecular biology and metabolic engineering have provided new insights and techniques for increasing biomass and biohydrogen production, and recent efforts in synthetic biology have demonstrated that complex regulatory and metabolic networks can be designed and engineered in microorganisms. Here, we explore how light-driven processes may be incorporated into nonphotosynthetic microbes to boost metabolic capacity for the production of industrial and fine chemicals. Progress towards the introduction of light-driven proton pumping or anoxygenic photosynthesis into Escherichia coli to increase the efficiency of metabolically-engineered biosynthetic pathways is highlighted. PMID:18951642

Johnson, Ethan T; Schmidt-Dannert, Claudia

2008-12-01

346

Phosphate solubilizing microorganisms vs. phosphate mobilizing microorganisms: What separates a phenotype from a trait?  

Microsoft Academic Search

Soils are often high in insoluble mineral phosphates but deficient in the soluble orthophosphate (Pi) essential for the growth\\u000a of most plants and microorganisms. In agricultural crop production, phosphorous is second only to nitrogen in importance as\\u000a a fertilizer amendment so that phosphorus fertilizers are the world’s second largest bulk agricultural chemical and, therefore,\\u000a the second most widely applied chemical

A. H. Goldstein; P. U. Krishnaraj

347

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

348

On the Theory of Killing Orbits in Space-Time  

E-print Network

This paper gives a theoretical discussion of the orbits and isotropies which arise in a space-time which admits a Lie algebra of Killing vector fields. The submanifold structure of the orbits is explored together with their induced Killing vector structure. A general decomposition of a space-time in terms of the nature and dimension of its orbits is given and the concept of stability and instability for orbits introduced. A general relation is shown linking the dimensions of the Killing algebra, the orbits and the isotropies. The well-behaved nature of "stable" orbits and the possible miss-behaviour of the "unstable" ones is pointed out and, in particular, the fact that independent Killing vector fields in space-time may not induce independent such vector fields on unstable orbits. Several examples are presented to exhibit these features. Finally, an appendix is given which revisits and attempts to clarify the well-known theorem of Fubini on the dimension of Killing orbits.

G. S. Hall

2003-10-14

349

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

350

Dual role of phagocytic NADPH oxidase in bacterial killing.  

PubMed

The classical model of bacterial killing by phagocytic cells has been recently challenged by questioning the toxic effect of oxygen products and attributing the fundamental role to K(+) ions in releasing antimicrobial proteins within the phagosome. In the present study we followed O(2)(*-) production, changes of membrane potential, K(+) efflux, and bacterial killing in the presence of increasing concentrations of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor diphenylene iodonium. Efficiency of bacterial killing was assessed on the basis of bacterial survival measured by a new semiautomated method. Very low rates of O(2)(*-) production were accompanied by significant membrane depolarization and K(+) release and parallel improvement of bacterial killing. When O(2)(*-) production exceeded 20% of its maximal capacity, no further change was detected in the membrane potential and only minimal further K(+) efflux occurred, yet bacterial survival decreased parallel to the increase of O(2)(*-) production. The presented results indicate that both electrophysiological changes (depolarization and consequent ion movements) and the chemical effect of reactive oxygen species play a significant role in the killing of certain pathogens. The observation that an increase of membrane depolarization can compensate for decreased O(2)(*-) production may be important for potential therapeutic applications. PMID:15251984

Rada, Balázs K; Geiszt, Miklós; Káldi, Krisztina; Timár, Csaba; Ligeti, Erzsébet

2004-11-01

351

Interactions between novel micro-organisms and intestinal flora  

Microsoft Academic Search

Microbial strains traditionally used to ferment food have a long history of safe use and are, therefore, considered as generally recognised as safe. Many of these micro-organisms have also functional attributes and are included among probiotics. New species and strains of bacteria with desirable technological and functional properties are constantly being identified; in addition, micro-organisms can be engineered by recently

P. Aureli; G. Franciosa

2002-01-01

352

Climate change effects on beneficial plant-microorganism interactions.  

PubMed

It is well known that beneficial plant-associated microorganisms may stimulate plant growth and enhance resistance to disease and abiotic stresses. The effects of climate change factors such as elevated CO(2), drought and warming on beneficial plant-microorganism interactions are increasingly being explored. This now makes it possible to test whether some general patterns occur and whether different groups of plant-associated microorganisms respond differently or in the same way to climate change. Here, we review the results of 135 studies investigating the effects of climate change factors on beneficial microorganisms and their interaction with host plants. The majority of studies showed that elevated CO(2) had a positive influence on the abundance of arbuscular and ectomycorrhizal fungi, whereas the effects on plant growth-promoting bacteria and endophytic fungi were more variable. In most cases, plant-associated microorganisms had a beneficial effect on plants under elevated CO(2). The effects of increased temperature on beneficial plant-associated microorganisms were more variable, positive and neutral, and negative effects were equally common and varied considerably with the study system and the temperature range investigated. Moreover, numerous studies indicated that plant growth-promoting microorganisms (both bacteria and fungi) positively affected plants subjected to drought stress. Overall, this review shows that plant-associated microorganisms are an important factor influencing the response of plants to climate change. PMID:20528987

Compant, Stéphane; van der Heijden, Marcel G A; Sessitsch, Angela

2010-08-01

353

The occurrence of microorganisms in water main encrustations  

Microsoft Academic Search

Colonization of microorganisms and resultant high bacterial populations often occur on or within protective encrustations or tubercules inside a distribution system. Formation of these encrustations is affected by a variety of physical, chemical, and biological activities within the pipes, which can be examined in situ by scanning electron microscopy (SEM). SEM photographs demonstrate graphically the survival of microorganisms in the

Martin J. Allen; Raymond H. Taylor; Edwin E. Geldreich

1980-01-01

354

Microorganisms in Food--Their Significance and Methods of Enumeration.  

ERIC Educational Resources Information Center

Described are laboratory methods for enumerating microorganisms in food. These methods are utilized to determine if foods are potentially hazardous to the consumer due to high concentrations of microorganisms. Discussed are indicator organisms, including coliforms, interococci, yeasts, and molds; food poisoning organisms (staphylococci and…

Andrews, S.

1980-01-01

355

A new electromagnetic positioning method for tracking invaded medical devices using MARG sensors  

NASA Astrophysics Data System (ADS)

In clinical medicine, electromagnetic tracking (EMT) system, with its safely penetrating property for human tissue, has been an effective tracking and guiding method for invaded medical devices which are invisible inside a human body. However, traditional EMT system only implements magnetic methods to solve the complex 6-DOF equations and demands an ideal magnetic-field distribution model exited by electromagnetic coils or permanent magnet, resulting in poor anti-interference performance. This paper proposed a new method, combining EMT with the attitude convergence algorithm using MARG sensors. This fusion method reduces the information reliability on the external field, simplifies the complexity of magnetic analysis, and improves the robustness. Except for the accuracy testify experiment, we impose artificial interference to the DC voltage which excites external electromagnetic coils, and the tracking system could still maintain a high positioning stability.

Wang, Sen; Chen, Xiao-dong; Du, Cheng-yang; Wang, Yi; Yu, Dao-yin

2013-08-01

356

Skull base tumor invading both cavernous sinuses. Adenoid cystic carcinoma mimicking a meningioma.  

PubMed

We present a case of an anterior skull base tumor invading both cavernous sinuses and extending into the right orbit in a 55 years old female. The radiological aspect was confusing, being highly suggestive for an extensively invasive meningioma. However, the orbital portion of the tumor, which was surgically removed, proved to be an adenoid cystic carcinoma. Some peculiar immunohistochemical findings were obvious, as well as a lack of continuity of the tumor with the local lacrimal gland. This is an unusual situation, when a lacrimal gland tumor spread along the cavernous sinus, cross the midline and approaches the contralateral orbit. Such local extension should be considered in the differential diagnosis of anterior skull base tumors. PMID:17392985

Arsene, D; Ardeleanu, Carmen; D?n?il?, L

2006-01-01

357

[Effectiveness of oxyclozanide in cattle naturally invaded by Liorchis scotiae trematoda].  

PubMed

The paper reports on the results of the clinical tests for the effectiveness of oxyclozanide pure substance (produced by ICI, U.K.) in cattle naturally invaded by the paramphistomata Liorchis scotiae. Helminthological dissection, performed 21 days after a single application of 15 mg oxyclozanide per 1 kg 1. w., revealed 87.5% intenseffectiveness on sexually mature paramphistomata on 85% intenseffectiveness on juvenile paramphistomata. The extenseffectiveness of the chemical was equal to zero. The coprological examinations performed for the three weeks in one-week intervals after therapy showed a decline in the number of produced eggs. The animals were given the medicated feed containing oxyclozanide only after preceding starvation. The chemical did not produce any unfavourable side effects or signs. PMID:828347

Corba, J; Pacenovský, J; Krupicer, I; Breza, M; Popovic, S; Reisz, T

1976-01-01

358

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

359

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, Søren; Ramsey, Philip W

2014-01-01

360

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

361

Early Postoperative Intraperitoneal Chemotherapy for Macroscopically Serosa-Invading Gastric Cancer Patients  

PubMed Central

Purpose Peritoneal recurrence is one of the most common patterns of recurrence after gastric cancer surgery and it has a poor prognosis despite all efforts. The aim of this study is to evaluate the prognostic impact of early postoperative intraperitoneal chemotherapy (EPIC) after surgery with curative intent for macroscopically serosa-invading gastric cancer patients. Materials and Methods The records of 245 patients under the age of 70 were reviewed. These patients were suffering from macroscopically seroa-invading gastric cancer and they underwent curative surgery from 1995 to 2004 at the Kyungpook National University Hospital, Daegu, Korea. The overall survival, gastric cancer-specific survival, complications, and patterns of recurrence were compared between the patients who were treated with EPIC and those who were not. Results EPIC was administered to 65 patients, and the remaining 180 patients did not receive this treatment. The 5-year overall and gastric cancer-specific survival rates for the EPIC group were 47.4% and 53.1%, respectively, and those for the non-EPIC group were 26.7% and 29.7%, respectively (p=0.012 for overall survival and p=0.011 for gastric cancer-specific survival). The rates of peritoneal recurrence for the EPIC group and the non-EPIC group were 18.5% and 32.2%, respectively (p=0.038). There were no significant differences in the morbidity or mortality between the two groups. Based on a multivariate analysis of the factors with prognostic significance in univariate analyses, EPIC, pathological lymph node metastasis, differentiation, and the extent of gastric resection were independent prognostic factors. Conclusion The use of EPIC to treat gastric cancer patients with macroscopic serosal invasions resulted in better survival rate by reducing the risk of peritoneal recurrence. PMID:25038762

Kwon, Oh Kyoung; Chung, Ho Young; Yu, Wansik

2014-01-01

362

The anomalous diffusion of a tumor invading with different surrounding tissues.  

PubMed

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

363

Immunology 101 Killing in acute viral infections Killing in chronic viral infections Appendix I Appendix II Extra Mathematical models of CD8 T cell responses  

E-print Network

Immunology 101 Killing in acute viral infections Killing in chronic viral infections Appendix I in vivo Vitaly V. Ganusov Los Alamos National Laboratory Los Alamos, NM, USA 1 / 55 #12;Immunology 101 1 Immunology 101 Immune system 2 Killing in acute viral infections Experimental details Model 3

Haase, Markus

364

Adenosine receptor antagonists effect on plasma-enhanced killing.  

PubMed

Previous studies demonstrated that naive plasma has inherent capabilities to enhance bacterial opsonization and phagocyte killing, but not all plasma is equally effective. This raised the question of whether plasma constituents other than opsonins may play a role. Adenosine receptor antagonists have been shown to modulate cytokine response and survival in mice after a bacterial challenge. We investigated whether selective adenosine receptor blockade would influence the ability of naive plasma to effectively control bacterial growth. Colonic bacteria- and thioglycollate-elicited peritoneal macrophages and neutrophils were obtained from naive mice. Stock murine plasma from naive was purchased and categorized as having high plasma-enhanced bacterial killing capacity using our previously described methods. Bacteria and plasma were incubated to allow for opsonization and then added to macrophages previously exposed to selected adenosine receptor antagonists: ZM 241385: A2A, MRS1754: A2B, DPCPX: A1, and MRS1220: A3. The final mixture was plated on blood agar plates in aerobic and anaerobic conditions and bacterial colony-forming units quantified after 24 h. This study demonstrated that exogenous adenosine was able to significantly decrease phagocyte killing of cecal bacteria. Blocking adenosine receptors with selective antagonists altered the bacterial killing capacity of plasma. Selectively blocking the A1, A2A, or A2B receptors proved most beneficial at reversing the effect of adenosine. Consistent with previous work, only macrophage killing of bacteria could be modulated by adenosine receptor blockade because neutrophils were unaffected. These data demonstrate that adenosine decreases macrophage killing of enteric bacteria and that this effect is mediated through the adenosine receptors. PMID:24089004

Bauzá, Gustavo; Moitra, Rituparna; Remick, Daniel

2014-01-01

365

RNA polymerase gene, microorganism having said gene and the production of RNA polymerase by the use of said microorganism  

DOEpatents

SP6 bacteriophage RNA polymerase is produced by cultivating a new microorganism (particularly new strains of Escherichia coli) harboring a plasmid that carries SP6 bacteriophage RNA polymerase gene and recovering SP6 bacteriophage RNA polymerase from the culture broth. SP6 bacteriophage RNA polymerase gene is provided as are new microorganisms harboring a plasmid that carries SP6 bacteriophage RNA polymerase gene.

Kotani, Hirokazu (Muko, JP); Hiraoka, Nobutsugu (Muko, JP); Obayashi, Akira (Uji, JP)

1991-01-01

366

Autonomous support for microorganism research in space  

NASA Technical Reports Server (NTRS)

A preliminary design for performing on-orbit, autonomous research on microorganisms and cultured cells/tissues is presented. An understanding of gravity and its effects on cells is crucial for space exploration as well as for terrestrial applications. The payload is designed to be compatible with the COMmercial Experiment Transported (COMET) launch vehicle, an orbiter middeck locker interface, and with Space Station Freedom. Uplink/downlink capabilities and sample return through controlled reentry are available for all carriers. Autonomous testing activities are preprogrammed with inflight reprogrammability. Sensors for monitoring temperature, pH, light, gravity levels, vibration, and radiation are provided for environmental regulation and experimental data collection. Additional experiment data acquisition includes optical density measurement, microscopy, video, and file photography. Onboard full data storage capabilities are provided. A fluid transfer mechanism is utilized for inoculation, sampling, and nutrient replenishment of experiment cultures. In addition to payload design, representative experiments were developed to ensure scientific objectives remained compatible with hardware capabilities. The project is defined to provide biological data pertinent to extended duration crewed space flight including crew health issues and development of a Controlled Ecological Life Support System (CELSS). In addition, opportunities are opened for investigations leading to commercial applications of space, such as pharmaceutical development, modeling of terrestrial diseases, and material processing.

Luttges, M. W.; Klaus, D. M.; Fleet, M. L.; Miller, M. S.; Shipley, D. E.; Smith, J. D.

1992-01-01

367

Sampling for metabolome analysis of microorganisms.  

PubMed

In the present work we investigated the most commonly applied methods used for sampling of microorganisms in the field of metabolomics in order to unravel potential sources of error previously ignored but of utmost importance for accurate metabolome analysis. To broaden the significance of our study, we investigated different Gram-negative and Gram-positive bacteria, i.e., Bacillus subtilis, Corynebacterium glutamicum, Escherichia coli, Gluconobacter oxydans, Pseudomonas putida, and Zymononas mobilis, and analyzed metabolites from different catabolic and anabolic intracellular pathways. Quenching of cells with cold methanol prior to cell separation and extraction led to drastic loss (>60%) of all metabolites tested due to unspecific leakage. Using fast filtration, Gram-negative bacteria also revealed a significant loss (>80%) when inappropriate washing solutions with low ionic strength were applied. Adapting the ionic strength of the washing solution to that of the cultivation medium could almost completely avoid this problem. Gram-positive strains did not show significant leakage independent of the washing solution. Fast filtration with sampling times of several seconds prior to extraction appears to be a suitable approach for metabolites with relatively high intracellular level and low turnover such as amino acids or TCA cycle intermediates. Comparison of metabolite levels in the culture supernatant and the cell interior revealed that the common assumption of whole broth quenching protocols attributing the metabolites found exclusively to the intracellular pools may not be valid in many cases. In such cases a differential approach correcting for medium-contained metabolites is required. PMID:17411014

Bolten, Christoph J; Kiefer, Patrick; Letisse, Fabien; Portais, Jean-Charles; Wittmann, Christoph

2007-05-15

368

Autonomous support for microorganism research in space  

NASA Technical Reports Server (NTRS)

A preliminary design for performing on orbit, autonomous research on microorganisms and cultured cells/tissues is presented. An understanding of gravity and its effects on cells is crucial for space exploration as well as for terrestrial applications. The payload is designed to be compatible with the Commercial Experiment Transporter (COMET) launch vehicle, an orbiter middeck locker interface, and with Space Station Freedom. Uplink/downlink capabilities and sample return through controlled reentry are available for all carriers. Autonomous testing activities are preprogrammed with in-flight reprogrammability. Sensors for monitoring temperature, pH, light, gravity levels, vibrations, and radiation are provided for environmental regulation and experimental data collection. Additional experimental data acquisition includes optical density measurement, microscopy, video, and film photography. On-board full data storage capabilities are provided. A fluid transfer mechanism is utilized for inoculation, sampling, and nutrient replenishment of experiment cultures. In addition to payload design, representative experiments were developed to ensure scientific objectives remained compatible with hardware capabilities. The project is defined to provide biological data pertinent to extended duration crewed space flight including crew health issues and development of a Controlled Ecological Life Support System (CELSS). In addition, opportunities are opened for investigations leading to commercial applications of space, such as pharmaceutical development, modeling of terrestrial diseases, and material processing.

Fleet, Mary L.; Miller, Mark S.; Shipley, Derek, E.; Smith, Jeff D.

1992-01-01

369

Rapidly evolving microorganisms with high biofuel tolerance  

NASA Astrophysics Data System (ADS)

Replacing non-renewable energy sources is one of the biggest and most exciting challenges of our generation. Algae and bacteria are poised to become major renewable biofuels if strains can be developed that provide a high,consistent and robust yield of oil. One major stumbling block towards this goal is the lack of tolerance to high concentrations of biofuels like isobutanol. Using traditional bioengineering techniques to remedy this face the hurdle of identifying the correct pathway or gene to modify. But the multiplicity of interactions inside a cell makes it very hard to determine what to modify a priori. Instead, we propose a technology that does not require prior knowledge of the genes or pathways to modify. In our approach that marries microfabrication and ecology, spatial heterogeneity is used as a knob to speed up evolution in the desired direction. Recently, we have successfully used this approach to demonstrate the rapid emergence of bacterial antibiotic resistance in as little as ten hours. Here, we describe our experimental results in developing new strains of micro-organisms with high oil tolerance. Besides biofuel production, our work is also relevant to oil spill clean-ups.

Vyawahare, Saurabh; Zhang, Qiucen; Lang, Wendy; Austin, Robert

2012-02-01

370

Summary. The Argentine ant, Linepithema humile, has invaded many areas of the world, displacing native ants. Its  

E-print Network

Summary. The Argentine ant, Linepithema humile, has invaded many areas of the world, displacing native ants. Its behavior may contribute to its competitive success. Staged and natural encounters were observed at food resources in the field, between Argentine ants and eight ant species native to northern

Gordon, Deborah

371

Reshaping the Ecology of Invading Populations of Hemlock Woolly Adelgid, Adelges tsugae (Homoptera: Adelgidae), in Eastern North America  

Microsoft Academic Search

Hemlock woolly adelgid, Adelges tsugae Annand (Homoptera: Adelgidae), is native to Japan where it is an innocuous inhabitant of Tsuga diversifolia Masters and T. sieboldii Carriere throughout their natural growing areas. Native adelgid populations are regulated by host resistance and natural enemies, in particular the oribatid mite, Diapterobates humeralis (Hermann) and the coccinellid beetle, Pseudoscymnus tsugae Sasaji and McClure. Invading

Mark S. McClure; Carole A. S.-J. Cheah

1999-01-01

372

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

E-print Network

, including many viruses and fungi, as well as bacteria. Because plant and animal immune systems haveLike 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

373

Elevated CO 2 differentially alters belowground plant and soil microbial community structure in reed canary grass-invaded experimental wetlands  

Microsoft Academic Search

Several recent studies have indicated that an enriched atmosphere of carbon dioxide (CO2) could exacerbate the intensity of plant invasions within natural ecosystems, but little is known of how rising CO2 impacts the belowground characteristics of these invaded systems. In this study, we examined the effects of elevated CO2 and nitrogen (N) inputs on plant and soil microbial community characteristics

Jenny Kao-Kniffin; Teri C. Balser

2007-01-01

374

[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

375

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

376

Impact of Exotic Invertebrate Invaders on Food Web Structure and Function in the Great Lakes: a Network Analysis Approach  

E-print Network

Impact of Exotic Invertebrate Invaders on Food Web Structure and Function in the Great Lakes a second wave of species invasions dominated by exotic invertebrates- Zebra mussels (Dreissena polymorpha invasions (e.g., sea Lamprey and Alewife), these invertebrates inserted themselves in the lower trophic

377

Are microorganisms more effective than plants at competing for nitrogen?  

PubMed

Plant scientists have long debated whether plants or microorganisms are the superior competitor for nitrogen in terrestrial ecosystems. Microorganisms have traditionally been viewed as the victors but recent evidence that plants can take up organic nitrogen compounds intact and can successfully acquire N from organic patches in soil raises the question anew. We argue that the key determinants of 'success' in nitrogen competition are spatial differences in nitrogen availability and in root and microbial distributions, together with temporal differences in microbial and root turnover. Consequently, it is not possible to discuss plant-microorganism competition without taking into account this spatiotemporal context. PMID:10871903

Hodge, A; Robinson, D; Fitter, A

2000-07-01

378

Hypervelocity impact of spaced plates by a mock kill vehicle  

Microsoft Academic Search

In support of the National Missile Defense (NMD) program, a series of Light Gas Gun (LGG) lethality tests were conducted at the Arnold Engineering Development Center (AEDC). A new projectile was designed for this test series that would be representative of aspects of a generic NMD system kill vehicle. A series of projectile development tests were performed during the design

James S. Wilbeck; Stephen B. Herwig; Jon M. Kilpatrick; Douglas R. Faux; Robert J. Weir; Eugene S. Hertel; Milan K. Dutta

2001-01-01

379

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 found on mule deer win- ter ranges in the foothills of the Bitterroot Moun- tains and white-tailed deer). White-tailed deer ranges were mostly in old- growth forests. The Clearwater and Swan rivers

Harris, Richard B.

380

Evolution Operators for Linearly Polarized Two-Killing Cosmological Models  

E-print Network

We give a general procedure to obtain non perturbative evolution operators in closed form for quantized linearly polarized two Killing vector reductions of general relativity with a cosmological interpretation. We study the representation of these operators in Fock spaces and discuss in detail the conditions leading to unitary evolutions.

J. Fernando Barbero G.; Daniel Gómez Vergel; Eduardo J. S. Villaseñor

2006-06-15

381

ORIGINAL ARTICLE Nafcillin enhances innate immune-mediated killing  

E-print Network

to daptomycin was used to treat refractory methicillin-resistant Staphylococcus aureus (MRSA) bacteremia against MRSA were examined in vitro and in vivo. Exposures to -lactam antimicrobials in general, neutrophils, and platelets. This finding correlated with enhanced killing of MRSA by whole blood, neutrophils

Nizet, Victor

382

Pulpability of beetle-killed spruce. Forest Service research paper  

Microsoft Academic Search

Infestation of the Dendroctonus rufipennis beetle has resulted in large stands of dead and dying timber on the Kenai Peninsula in Alaska. Tests were conducted to evaluate the value of beetle-killed spruce as pulpwood. The results showed that live and dead spruce wood can be pulped effectively. The two least deteriorated classes and the most deteriorated class of logs had

G. M. Scott; D. W. Bormett; N. R. Sutherland; S. Abubakr; E. Lowell

1996-01-01

383

Illegal killing for ivory drives global decline in African elephants.  

PubMed

Illegal wildlife trade has reached alarming levels globally, extirpating populations of commercially valuable species. As a driver of biodiversity loss, quantifying illegal harvest is essential for conservation and sociopolitical affairs but notoriously difficult. Here we combine field-based carcass monitoring with fine-scale demographic data from an intensively studied wild African elephant population in Samburu, Kenya, to partition mortality into natural and illegal causes. We then expand our analytical framework to model illegal killing rates and population trends of elephants at regional and continental scales using carcass data collected by a Convention on International Trade in Endangered Species program. At the intensively monitored site, illegal killing increased markedly after 2008 and was correlated strongly with the local black market ivory price and increased seizures of ivory destined for China. More broadly, results from application to continental data indicated illegal killing levels were unsustainable for the species between 2010 and 2012, peaking to ? 8% in 2011 which extrapolates to ? 40,000 elephants illegally killed and a probable species reduction of ? 3% that year. Preliminary data from 2013 indicate overharvesting continued. In contrast to the rest of Africa, our analysis corroborates that Central African forest elephants experienced decline throughout the last decade. These results provide the most comprehensive assessment of illegal ivory harvest to date and confirm that current ivory consumption is not sustainable. Further, our approach provides a powerful basis to determine cryptic mortality and gain understanding of the demography of at-risk species. PMID:25136107

Wittemyer, George; Northrup, Joseph M; Blanc, Julian; Douglas-Hamilton, Iain; Omondi, Patrick; Burnham, Kenneth P

2014-09-01

384

Karo-kari: a form of honour killing in pakistan.  

PubMed

Karo-Kari is a type of premeditated honour killing, which originated in rural and tribal areas of Sindh, Pakistan. The homicidal acts are primarily committed against women who are thought to have brought dishonour to their family by engaging in illicit pre-marital or extra-marital relations. In order to restore this honour, a male family member must kill the female in question. We conducted a systematic review of the published literature other sources on karo-kari and related forms of honour killing or violence against women. Media and non-governmental organization reports were utilized for case studies and analysis. Although legally proscribed, socio-cultural factors and gender role expectations have given legitimacy to karo-kari within some tribal communities. In addition to its persistence in areas of Pakistan, there is evidence that karo-kari may be increasing in incidence in other parts of the world in association with migration. Moreover, perpetrators of ;honour killings' often have motives outside of female adultery. Analysis of the socio-cultural and psycho-pathological factors associated with the practice of karo-kari can guide the development of prevention strategies. PMID:19091732

Patel, Sujay; Gadit, Amin Muhammad

2008-12-01

385

PYRAPERM KILLS FLEAS AND HALTS PLAGUE AMONG UTAH PRAIRIE DOGS  

Microsoft Academic Search

Plague is an introduced bacterial disease whose primary vectors are fleas (Siphon- aptera). Utah prairie dogs (Cynomys parvidens) are highly susceptible to plague, and entire colonies usually disappear shortly after plague arrives. Infusion of burrows with Pyraperm (an insecticide- dust) kills fleas and immediately halts the spread of plague within colonies. Thus, insecticide-dusts might play an important role in the

John L. Hoogland; Stacey Davis; Sarah Benson-Amram; Danielle Labruna; Brigitte Goossens; Margaret A. Hoogland; Cheri A. Jones

2004-01-01

386

Licence to Kill: About Accreditation Issues and James Bond  

ERIC Educational Resources Information Center

Accreditation has become something of a hot topic in higher education. In Europe it has been described as a 'Licence to Kill'. The James Bond metaphor is particularly illustrative when reflecting on quality assurance challenges in higher education. Publications on this subject in recent years reveal that the array of issues associated with…

Scheele, Ko

2004-01-01

387

Population genetics of the frog-killing fungus Batrachochytrium dendrobatidis  

E-print Network

Population genetics of the frog-killing fungus Batrachochytrium dendrobatidis Jess A. T. Morgan comparison of Batrachochytrium dendrobatidis isolates from an intensively studied region of frog decline-host specificity, little correlation between fungal genotype and geography, local frog extirpation by a single

California at Berkeley, University of

388

Killing for Girls: Predation Play and Female Empowerment  

ERIC Educational Resources Information Center

Predation games--games in which the player is actively encouraged and often required to hunt and kill in order to survive--have historically been the purview of male players. Females, though now much more involved in digital games than before, generally play games that stress traditionally feminine values such as socializing with others, shopping,…

Bertozzi, Elena

2012-01-01

389

SHORT COMMUNICATION Behaviour of brown bears killing wild ungulates  

E-print Network

SHORT COMMUNICATION Behaviour of brown bears killing wild ungulates in the Cantabrian Mountains /Published online: 11 November 2010 # Springer-Verlag 2010 Abstract Although brown bears (Ursus arctos documentation regarding bear predation on wild ungulates in Southern Europe. We describe search, detection

Boyer, Edmond

390

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

E-print Network

and environmental experts from the New York region. A research project of Columbia University's Earth InstituteLife After Fresh Kills: Moving Beyond New York City's Current Waste Management Plan Policy,Technical and Environmental Considerations December 1, 2001 A joint research project of Columbia University's Earth Institute

Columbia University

391

21. New York Connecting Railroad: Bronx Kill Bridge. Randalls Island, ...  

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

21. New York Connecting Railroad: Bronx Kill Bridge. Randalls Island, New York Co., NY. Sec. 4207, MP 8.54. - Northeast Railroad Corridor, Amtrak Route between New Jersey/New York & New York/Connecticut State Lines, New York, New York County, NY

392

22. New York Connecting Railroad: Bronx Kill Bridge. Randalls Island, ...  

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

22. New York Connecting Railroad: Bronx Kill Bridge. Randalls Island, New York Co., NY. Sec. 4207, MP 8.54. - Northeast Railroad Corridor, Amtrak Route between New Jersey/New York & New York/Connecticut State Lines, New York, New York County, NY

393

20. Bronx Kill Bridge with Hell Gate Bridge in background. ...  

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

20. Bronx Kill Bridge with Hell Gate Bridge in background. Randalls Island, New York Co., NY. Sec. 4207, MP 8.54. - Northeast Railroad Corridor, Amtrak Route between New Jersey/New York & New York/Connecticut State Lines, New York, New York County, NY

394

Phototoxic aptamers selectively enter and kill epithelial cancer cells  

Microsoft Academic Search

The majority of cancers arise from malignant epithe- lial cells. We report the design of synthetic oligo- nucleotides (aptamers) that are only internalized by epithelial cancer cells and can be precisely acti- vated by light to kill such cells. Specifically, photo- toxic DNA aptamers were selected to bind to unique short O-glycan-peptide signatures on the surface of breast, colon, lung,

Catia S. M. Ferreira; Melissa C. Cheung; Sotiris Missailidis; Stuart Bisland; Jean Gariepy

2009-01-01

395

RESEARCH ARTICLE The Evolution of Reduced Microbial Killing  

E-print Network

RESEARCH ARTICLE The Evolution of Reduced Microbial Killing Jan A. C. Vriezen, Michael Valliere race in which they compete for limited resources and niche space. The outcome of this intense interaction is the evolution of a powerful arsenal of biological weapons. Perhaps the most studied

Riley, Margaret

396

Tree-Killing Las Conchas Fire in New Mexico  

USGS Multimedia Gallery

USGS scientist Craig D. Allen observes the results of the extensive, tree-killing fire that consumed almost all above-ground biomass in this part of the Las Conchas Fire burn area in the Jemez Mountains, New Mexico. Photo taken in late August 2011, two months post-fire. Forest drought stress is high...

397

PREDATION AND MULTIPLE KILLS OF MUSKOXEN BY GRIZZLY BEARS  

Microsoft Academic Search

A population of muskoxen (Ovibos moschatus), successfully restored to northeastern Alaska in the 1970's, has become a source of food for grizzly bears (Ursus arctos). We tested whether grizzly bear predation on this population of muskoxen increased over time and described multiple kills of muskoxen by grizzly bears. We identified bear-muskox events from data collected between April 1982 and June

HARRY V. REYNOLDS; RICHARD T. SHIDELER

398

Heat Melt Compaction as an Effective Treatment for Eliminating Microorganisms from Solid Waste  

NASA Technical Reports Server (NTRS)

One of the technologies being tested at Ames Research Center as part of the logistics and repurposing project is heat melt compaction (HMC) of solid waste to reduce volume, remove water and render a biologically stable and safe product. Studies at Kennedy Space Center have focused on the efficacy of the heat melt compaction process for killing microorganisms in waste and specific compacter operation protocols, i.e., time and temperature, required to achieve a sterile, stable product. The work reported here includes a controlled study to examine the survival and potential re-growth of specific microorganisms over a 6-month period of storage after heating and compaction. Before heating and compaction, ersatz solid wastes were inoculated with Bacillus amyloliquefaciens and Rhodotorula mucilaginosa, previously isolated from recovered space shuttle mission food and packaging waste. Compacted HMC tiles were sampled for microbiological analysis at time points between 0 and 180 days of storage in a controlled environment chamber. In addition, biological indicator strips containing spores of Bacillus atrophaeus and Ceo bacillus stearothermophilus were imbedded in trash to assess the efficacy of the HMC process to achieve sterilization. Analysis of several tiles compacted at 180 C for times of 40 minutes to over 2 hours detected organisms in all tile samples with the exception of one exposed to 180 C for approximately 2 hours. Neither of the inoculated organisms was recovered, and the biological indicator strips were negative for growth in all tiles indicating at least local sterilization of tile areas. The findings suggest that minimum time/temperature combination is required for complete sterilization. Microbial analysis of tiles processed at lower temperatures from 130 C-150 C at varying times will be discussed, as well as analysis of the bacteria and fungi present on the compactor hardware as a result of exposure to the waste and the surrounding environment. The two organisms inoculated into the waste were among those isolated and identified from the HMC surfaces indicating the possibility of cross contamination.

Hummerick, Mary P.; Strayer, Richard; McCoy, LaShelle; Richard, Jeffrey; Ruby, Anna; Wheeler, Raymond

2012-01-01

399

Collective hydrodynamics of swimming micro-organisms  

NASA Astrophysics Data System (ADS)

Since the work of Kessler in the 1980s, and before, there has been considerable interest among fluid dynamicists and physicists in the collective behaviour of swimming micro-organisms in suspension. Since all such cells are denser than the water in which they swim, bioconvection patterns result from upswimming of cells in a chamber of finite depth and from gyrotaxis of bottom-heavy cells in a uniform fluid. Bioconvection has been analysed for dilute suspensions; the theory will be briefly re-examined with emphasis on the additional stress induced by the cells' swimming motions (each cell can be regarded as a force-dipole, or stresslet), because of the new instabilities revealed by Simha & Ramaswamy (2002) for uniform suspensions in the absence of gravity. Even more fascinating coherent structures arise in concentrated suspensions, of bacteria for example, in which cell-cell interactions cannot be ignored. The hypothesis is that such structures emerge from purely hydrodynamic interactions between cells. A variety of models have been developed, which are outlined briefly, but particular attention will be paid to our own model in which cells are represented as inertia-free ``spherical squirmers,'' whose behaviour is dominated by near-field hydrodynamics. Pairwise interactions are computed precisely, and Stokesian dynamics in a periodic box is used to simulate an infinite suspension. Trajectories are computed deterministically, but the long-time spreading of a 3D suspension, from random initial conditions, is diffusive; scaling arguments can be used to estimate the effective diffusivity. However, in 2D there is a strong tendency towards aggregation into clumps or bands. [Recent work reported here has been performed in collaboration with T Ishikawa and J T Locsei.

Pedley, Timothy

2007-11-01

400

Single cell genomics of subsurface microorganisms  

NASA Astrophysics Data System (ADS)

Recent studies have revealed unexpected abundance and diversity of microorganisms in terrestrial and marine subsurface, providing new perspectives over their biogeochemical significance, evolution, and the limits of life. The now commonly used research tools, such as metagenomics and PCR-based gene surveys enabled cultivation-unbiased analysis of genes encoded by natural microbial communities. However, these methods seldom provide direct evidence for how the discovered genes are organized inside genomes and from which organisms do they come from. Here we evaluated the feasibility of an alternative, single cell genomics approach, in the analysis of subsurface microbial community composition, metabolic potential and microevolution at the Sanford Underground Research Facility (SURF), South Dakota, and the Witwaterstrand Basin, South Africa. We successfully recovered genomic DNA from individual microbial cells from multiple locations, including ultra-deep (down to 3,500 m) and low-biomass (down to 10^3 cells mL^-1) fracture water. The obtained single amplified genomes (SAGs) from SURF contained multiple representatives of the candidate divisions OP3, OP11, OD1 and uncharacterized archaea. By sequencing eight of these SAGs, we obtained the first genome content information for these phylum-level lineages that do not contain a single cultured representative. The Witwaterstrand samples were collected from deep fractures, biogeochemical dating of which suggests isolation from tens of thousands to tens of millions of years. Thus, these fractures may be viewed as "underground Galapagos", a natural, long-term experiment of microbial evolution within well-defined temporal and spatial boundaries. We are analyzing multiple SAGs from these environments, which will provide detailed information about adaptations to life in deep subsurface, mutation rates, selective pressures and gene flux within and across microbial populations.

Stepanauskas, R.; Onstott, T. C.; Lau, C.; Kieft, T. L.; Woyke, T.; Rinke, C.; Sczyrba, A.; van Heerden, E.

2012-12-01

401

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

E-print Network

to biological invasions including plants, animals, and microbes. Biology and ecology of invasive species 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

Watson, Craig A.

402

Habitat heterogeneity influences restoration efficacy: Implications of a habitat-specific management regime for an invaded marsh  

NASA Astrophysics Data System (ADS)

Invasive species have to be managed to prevent adverse consequences. Spartina alterniflora has invaded many marshes where salinity and inundation are often key factors affecting vegetation. The former was surface clipped twice and native Phragmites australis was planted in invaded zones to examine the effects of habitat properties on the efficacy of invader control and native restoration. The results showed that two clipping treatments almost eliminated S. alterniflora in the zones with long inundation periods of 80 h/15 d but stimulated compensatory growth of S. alterniflora in the zones with short inundation periods. Transplanted P. australis performed better over time in zones with low salinity (<10.5 psu) but performed poorly in high-salinity zones, indicating that the efficacy of invader management and native restoration activities changes significantly along habitat gradients. With a progression from the dyke to the seaward side of the studied marsh, there was a long then short then long inundation period whereas salinity increased consistently. The study indicates that the high-frequency removal of the above-ground parts of S. alterniflora should be used only in the middle tidal zones and that native vegetation should be planted in zones above the mean high water level while the others zones in the saltmarsh should be restored to mud flats. Usually, invasive plants can flourish in highly heterogeneous habitats, which can influence management efficacy by influencing the re-growth of treated invaders and the performance of restored native species. Therefore, habitat-specific management regimes for invasive species can be expected to be more efficient because of their dependence on specific habitats.

Tang, Long; Gao, Yang; Wang, Cheng-Huan; Li, Bo; Chen, Jia-Kuan; Zhao, Bin

2013-07-01

403

A Note on Teleparallel Killing Symmetries in Three Dimensional Circularly Symmetric Static Spacetime  

NASA Astrophysics Data System (ADS)

In this article we investigate Killing vectors in three dimensional Lorentzian manifold for circularly symmetric static spacetime in the presence of torsion. Teleparallel Killing equations are obtained and then solved by using some algebraic and direct integration techniques. This study reveals that the above spacetime admit two, three, four, five or six teleparallel Killing vectors. We compare our results with the available results in general relativity where the same spacetime admit two, three, four or six Killing vectors. It turns out that the teleparallel Killing vectors are different from Killing vectors in general relativity for the same spacetime.

Khan, Suhail; Hussain, Tahir; Ali Khan, Gulzar; Ali, Amjad

2015-01-01

404

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

405

Shifts in grassland invasibility: effects of soil resources, disturbance, composition, and invader size.  

PubMed

There is an emerging recognition that invasibility is not an intrinsic community trait, but is a condition that fluctuates from interactions between environmental forces and residential characters. Elucidating the spatiotemporal complexities of invasion requires inclusion of multiple, ecologically variable factors within communities of differing structure. Water and nutrient amendments, disturbance, and local composition affect grassland invasibility but no study has simultaneously integrated these, despite evidence that they frequently interact. Using a split-plot factorial design, we tested the effects of these factors on the invasibility of C3 pasture communities by smooth pigweed Amaranthus hybridus L., a problematic C4 forb. We sowed seeds and transplanted 3-week old seedlings of A. hybridus into plots containing monocultures and mixtures of varying composition, subjected plots to water, soil disturbance, and synthetic bovine urine (SBU) treatments, and measured A. hybridus emergence, recruitment, and growth rate. Following SBU addition, transplanted seedling growth increased in all plots but differed among legume and nonlegume monocultures and mixtures of these plant types. However, SBU decreased the number and recruitment rate of emerged seedlings because high residential growth reduced light availability. Nutrient pulses can therefore have strong but opposing effects on invasibility, depending on when they coincide with particular life history stages of an invader. Indeed, in SBU-treated plots, small differences in height of transplanted seedlings early on produced large differences in their final biomass. All facilitative effects of small-scale disturbance on invasion success diminished when productivity-promoting factors were present, suggesting that disturbance patch size is important. Precipitation-induced invasion resistance of C3 pastures by a C4 invader was partly supported. In grazed grasslands, these biotic and environmental factors vary across scales and interact in complex ways to affect invasibility, thus a dynamic patch mosaic of differential invasion resistance likely occurs in single fields. We propose that disturbance patch size, grazing intensity, soil resource availability, and resident composition are inextricably linked to grassland invasions and comment on the utility of community attributes as reliable predictors of invasibility. Lastly, we suggest temporal as well as spatial coincidences of multiple invasion facilitators dictate the window of opportunity for invasion. PMID:16995627

Renne, Ian J; Tracy, Benjamin F; Colonna, Ignacio A

2006-09-01

406

Targeted Killing of Streptococcus mutans by a Pheromone-Guided \\  

Microsoft Academic Search

Within the repertoire of antibiotics available to a prescribing clinician, the majority affect a broad range of microorganisms, including the normal flora. The ecological disruption resulting from antibiotic treatment frequently results in secondary infections or other negative clinical consequences. To address this problem, our laboratory has recently developed a new class of pathogen-selective molecules, called specifically (or selectively) targeted antimicrobial

Randal Eckert; Jian He; Daniel K. Yarbrough; Fengxia Qi; Maxwell H. Anderson; Wenyuan Shi

2006-01-01

407

21 CFR 866.2660 - Microorganism differentiation and identification device.  

Code of Federal Regulations, 2010 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2660 Microorganism differentiation and identification...

2010-04-01

408

21 CFR 866.2660 - Microorganism differentiation and identification device.  

Code of Federal Regulations, 2013 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2660 Microorganism differentiation and identification...

2013-04-01

409

21 CFR 866.2660 - Microorganism differentiation and identification device.  

Code of Federal Regulations, 2014 CFR

... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2660 Microorganism differentiation and identification...

2014-04-01

410

RESEARCH ARTICLE Fluid dynamics of self-propelled microorganisms,  

E-print Network

RESEARCH ARTICLE Fluid dynamics of self-propelled microorganisms, from individuals to concentrated Introduction The fluid dynamics of fast, large self-propelled objects, ranging from krill to whales, mosquitoes

Cortez, Ricardo

411

Turbulent Fluid Acceleration Generates Clusters of Gyrotactic Microorganisms  

E-print Network

The motility of microorganisms is often biased by gradients in physical and chemical properties of their environment, with myriad implications on their ecology. Here we show that fluid acceleration reorients gyrotactic ...

De Lillo, Filippo

412

21 CFR 866.2660 - Microorganism differentiation and identification device.  

Code of Federal Regulations, 2012 CFR

...OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology...microorganism differentiation and identification device is a device intended for medical purposes that consists of one or more...

2012-04-01

413

21 CFR 866.2660 - Microorganism differentiation and identification device.  

Code of Federal Regulations, 2011 CFR

...OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology...microorganism differentiation and identification device is a device intended for medical purposes that consists of one or more...

2011-04-01

414

Collective Motion of Micro-organisms from Field Theoretical Viewpoint  

E-print Network

We analyze the collective motion of micro-organisms in the fluid and consider the problem of the red tide. The red tide is produced by the condensation of the micro-organisms, which might be a similar phenomenon to the condensation of the strings. We propose a model of the generation of the red tide. By considering the interaction between the micro- organisms mediated by the velocity fields in the fluid, we derive the Van der Waals type equation of state, where the generation of the red tide can be regarded as a phase transition from the gas of micro-organisms to the liquid. (The number density of micro-organisms which generates the red tide is order estimated.)

Shin'ichi Nojiri; Masako Kawamura; Akio Sugamoto

1995-12-13

415

Multiorganismal insects: diversity and function of resident microorganisms.  

PubMed

All insects are colonized by microorganisms on the insect exoskeleton, in the gut and hemocoel, and within insect cells. The insect microbiota is generally different from microorganisms in the external environment, including ingested food. Specifically, certain microbial taxa are favored by the conditions and resources in the insect habitat, by their tolerance of insect immunity, and by specific mechanisms for their transmission. The resident microorganisms can promote insect fitness by contributing to nutrition, especially by providing essential amino acids, B vitamins, and, for fungal partners, sterols. Some microorganisms protect their insect hosts against pathogens, parasitoids, and other parasites by synthesizing specific toxins or modifying the insect immune system. Priorities for future research include elucidation of microbial contributions to detoxification, especially of plant allelochemicals in phytophagous insects, and resistance to pathogens; as well as their role in among-insect communication; and the potential value of manipulation of the microbiota to control insect pests. PMID:25341109

Douglas, Angela E

2015-01-01

416

APPROACHES FOR DEFINING TREATABILITY AND DISINFECTION OF CCL MICROORGANISMS  

EPA Science Inventory

The product evaluates three disinfectant methods , chlorine, Ultraviolet light and ozone in their effectiveness against all the listed CCL microorganisms (bacteria, viruses and protozoa). Surrogates for nonculturable viruses were included. The susceptibility evaluation data of CP...

417

Technologies for Beneficial Microorganisms Inocula Used as Biofertilizers  

PubMed Central

The increasing need for environmentaly friendly agricultural practices is driving the use of fertilizers based on beneficial microorganisms. The latter belong to a wide array of genera, classes, and phyla, ranging from bacteria to yeasts and fungi, which can support plant nutrition with different mechanisms. Moreover, studies on the interactions between plant, soil, and the different microorganisms are shedding light on their interrelationships thus providing new possible ways to exploit them for agricultural purposes. However, even though the inoculation of plants with these microorganisms is a well-known practice, the formulation of inocula with a reliable and consistent effect under field conditions is still a bottleneck for their wider use. The choice of the technology for inocula production and of the carrier for the formulation is key to their successful application. This paper focuses on how inoculation issues can be approached to improve the performance of beneficial microorganisms used as a tool for enhancing plant growth and yield. PMID:22547984

Malusá, E.; Sas-Paszt, L.; Ciesielska, J.

2012-01-01

418

Fossil microorganisms and formation of Early Precambrian weathering crusts  

NASA Astrophysics Data System (ADS)

Weathering crusts are the only reliable evidences of continental conditions existence, and often are the only source of information about exogenous processes and subsequently about conditions under which the development of biosphere occurred. Complex of diverse fossil microorganisms was discovered in result of electronic-microscope investigations. Chemical composition of discovered fossils is identical to that of the host rocks and is represented by Si, Al, Fe, Ca and Mg. Probably, microorganisms fixed in rocks played role of catalyst. Decomposition of minerals, comprising rocks, and their transformation into clayey (argillaceous) minerals, occurred most likely under influence of microorganisms. And may be unique weathering crusts of Early Precambrian were formed due to interaction between specific composition of microorganism assemblage and conditions of hypergene transformations. So it is possible to speak about colonization of land by microbes already at that time and about existence of single raw from weathering crusts (Primitive soils) to real soils.

Astafieva, M. M.; Rozanov, A. Yu.; Vrevsky, A. B.; Alfimova, N. A.; Matrenichev, V. A.; Hoover, R. B.

2009-08-01

419

Main microorganisms involved in the fermentation of Ugandan ghee  

Microsoft Academic Search

Ghee is widely produced from a traditional fermented butter-like product named mashita in western Uganda. However, no detailed studies have been done to identify the microorganisms involved in mashita fermentation. The aim of this study was to identify the microorganisms present at the end of mashita ripening using culture-dependent and culture-independent techniques. The most commonly identified species of lactic acid

Martin Patrick Ongol; Kozo Asano

2009-01-01

420

Method for treating wastewater using microorganisms and vascular aquatic plants  

NASA Technical Reports Server (NTRS)

A method for treating wastewater compresses subjecting the wastewater to an anaerobic setting step for at least 6 hours and passing the liquid effluent from the anaerobic settling step through a filter cell in an upflow manner. There the effluent is subjected first to the action of anaerobic and facultative microorganisms, and then to the action of aerobic microorganisms and the roots of at least one vascular aquatic plant.

Wolverton, B. C. (inventor)

1983-01-01

421

Microorganisms having enhanced tolerance to inhibitors and stress  

SciTech Connect

The present invention provides genetically modified strains of microorganisms that display enhanced tolerance to stress and/or inhibitors such as sodium acetate and vanillin. The enhanced tolerance can be achieved by increasing the expression of a protein of the Sm-like superfamily such as a bacterial Hfq protein and a fungal Sm or Lsm protein. Further, the present invention provides methods of producing alcohol from biomass materials by using the genetically modified microorganisms of the present invention.

Brown, Steven D.; Yang, Shihui

2014-07-29

422

Microorganisms having enhanced resistance to acetate and methods of use  

SciTech Connect

The present invention provides isolated or genetically modified strains of microorganisms that display enhanced resistance to acetate as a result of increased expression of a sodium proton antiporter. The present invention also provides methods for producing such microbial strains, as well as related promoter sequences and expression vectors. Further, the present invention provides methods of producing alcohol from biomass materials by using microorganisms with enhanced resistance to acetate.

Brown, Steven D; Yang, Shihui

2014-10-21

423

Precipitation of Calcite by Indigenous Microorganisms to Strengthen Liquefiable Soils  

Microsoft Academic Search

Enrichments for indigenous microorganisms capable of hydrolyzing urea in the presence of CaCl2 were performed on potentially liquefiable saturated soils in both the laboratory and in situ. Following enrichment, treatment of soils with nutrients, CaCl2 and urea resulted in significant in situ precipitation of calcite, even at depth, by indigenous microorganisms. The biomineralized soils showed properties that indicate calcite precipitation

Malcolm B. Burbank; Thomas J. Weaver; Tonia L. Green; Barbara C. Williams; Ronald L. Crawford

2011-01-01

424

Microorganisms pumping iron: anaerobic microbial iron oxidation and reduction  

Microsoft Academic Search

Iron (Fe) has long been a recognized physiological requirement for life, yet for many microorganisms that persist in water, soils and sediments, its role extends well beyond that of a nutritional necessity. Fe(II) can function as an electron source for iron-oxidizing microorganisms under both oxic and anoxic conditions and Fe(III) can function as a terminal electron acceptor under anoxic conditions

Karrie A. Weber; Laurie A. Achenbach; John D. Coates

2006-01-01

425

Rotary Apparatus Concentrates And Separates Micro-Organisms  

NASA Technical Reports Server (NTRS)

Apparatus concentrates and separates swimming micro-organisms of different species into concentric rings in fluid. Fluid containing high concentration of desired species removed by use of small scoop placed into fluid at radius of one of rings formed by that species. Micro-organisms concentrated into concentric rings by combined dynamic effects of upward and horizontal components of swimming, rotation of dish, gravitation, and viscosity.

Noever, David A.

1992-01-01

426

Evaluation of the ecotoxicity of pollutants with bioluminescent microorganisms.  

PubMed

This chapter deals with the use of bioluminescent microorganisms in environmental monitoring, particularly in the assessment of the ecotoxicity of pollutants. Toxicity bioassays based on bioluminescent microorganisms are an interesting complement to classical toxicity assays, providing easiness of use, rapid response, mass production, and cost effectiveness. A description of the characteristics and main environmental applications in ecotoxicity testing of naturally bioluminescent microorganisms, covering bacteria and eukaryotes such as fungi and dinoglagellates, is reported in this chapter. The main features and applications of a wide variety of recombinant bioluminescent microorganisms, both prokaryotic and eukaryotic, are also summarized and critically considered. Quantitative structure-activity relationship models and hormesis are two important concepts in ecotoxicology; bioluminescent microorganisms have played a pivotal role in their development. As pollutants usually occur in complex mixtures in the environment, the use of both natural and recombinant bioluminescent microorganisms to assess mixture toxicity has been discussed. The main information has been summarized in tables, allowing quick consultation of the variety of luminescent organisms, bioluminescence gene systems, commercially available bioluminescent tests, environmental applications, and relevant references. PMID:25216953

Fernández-Piñas, Francisca; Rodea-Palomares, Ismael; Leganés, Francisco; González-Pleiter, Miguel; Angeles Muñoz-Martín, M

2014-01-01

427

Quantity analysis of micro-organisms in bottled water  

NASA Astrophysics Data System (ADS)

Water is necessary to human being and all kinds of animals and plants. In recently years, Bottled Water become the main drinking water whatever for families or for institutions. But most of them have no conception of the water's safety or quality. To have conceptions of the count and distributing of the microorganisms in bucket pure water, we use fluorescent microscope counting stained with SYBR Green I to research the microorganisms (including virus) quantity in Bottled Water for six samples produced in different place. Analyzing shows that the quantity of the microorganisms in these water are different. Some up to 11.912×106 virus/ m L. The quality of Bottled Water needs to be improved. And the quantity of microorganisms in the water is different with different ways to keep the water. At the same time, it shows that fluorescent microscope counting stained with SYBR Green I method is simple and high sensitive to such low microorganisms quantity water sample. It can be used in the microorganisms dynamic quantity research in drinking water.

Li, Juan; Li, Xiangyong

2008-12-01

428

Stressful environments induce novel phenotypic variation: hierarchical reaction norms for sperm performance of a pervasive invader  

PubMed Central

Genetic variation for phenotypic plasticity is ubiquitous and important. However, the scale of such variation including the relative variability present in reaction norms among different hierarchies of biological organization (e.g., individuals, populations, and closely related species) is unknown. Complicating interpretation is a trade-off in environmental scale. As plasticity can only be inferred over the range of environments tested, experiments focusing on fine tuned responses to normal or benign conditions may miss cryptic phenotypic variation expressed under novel or stressful environments. Here, we sought to discern the presence and shape of plasticity in the performance of brown trout sperm as a function of optimal to extremely stressful river pH, and demarcate if the reaction norm varies among genotypes. Our overarching goal was to determine if deteriorating environmental quality increases expressed variation among individuals. A more applied aim was to ascertain whether maintaining sperm performance over a wide pH range could help explain how brown trout are able to invade diverse river systems when transplanted outside of their native range. Individuals differed in their reaction norms of phenotypic expression of an important trait in response to environmental change. Cryptic variation was revealed under stressful conditions, evidenced through increasing among-individual variability. Importantly, data on population averages masked this variability in plasticity. In addition, canalized reaction norms in sperm swimming velocities of many individuals over a very large range in water chemistry may help explain why brown trout are able to colonize a wide variety of habitats. PMID:23145341

Purchase, Craig F; Moreau, Darek T R

2012-01-01

429

Surgical treatment of T3 lung cancer invading the chest wall.  

PubMed

Lung tumors invading the chest wall are classed as belonging to the T3 group and are considered potentially resectable. Their management, however, is controversial, and extrapleural resection, when possible, is preferred to en bloc resection which is regarded as a far more invasive and dangerous operation. Five year survival rates for completely resected cases range in the literature from 25 to 35%, but survival rates are much worse if lymph node metastases are present. These poor outcomes have prompted the development of combined surgical approaches: preoperative radiation therapy, with or without chemotherapy, has been used with an improvement in resectability rates, but only modest results in terms of median survival; in a number of case series, increased operative morbidity and mortality have been reported with this approach. The present report relates to 122 patients treated by en bloc (20 cases) or extrapleural (102 cases) resection, 31 of whom also received neoadjuvant treatment. The operative mortality was 4.6%. Median survival was 17 months after en bloc resection and 19 months after extrapleural resection. Though no statistically significant difference was found, extrapleural resection would appear to yield better results than the en bloc procedure. PMID:10742890

Beltrami, V; Bezzi, M; Illuminati, G; Forte, A; Angelici, A; Bertagni, A; Ciulli, A; Gallinaro, L; Lorenzotti, A; Montesano, G; Palumbo, P G; Prece, V

1999-01-01

430

Invading species in the Eel River, California: Successes, failures, and relationships with resident species  

USGS Publications Warehouse

We examined invasions of non-native fishes into the Eel River, California. At least 16 species of fish have been introduced into the drainage which originally supported 12-14 fish species. Our study was prompted by the unauthorized introduction in 1979 of Sacramento squawfish, Ptychocheilus grandis, a large predatory cyprinid. From 1986 to 1990, we conducted growth and diet studies of squaw fish, conducted intensive surveys of the distribution and habitat associations of both native and introduced species, and examined the nature of species-habitat and interspecies relationships. We found no evidence for increased growth or expanded feeding habits, compared to native populations, of Sacramento squawfish as they invaded the Eel River drainage. Ten of the introduced species were well established, with four species limited to a reservoir and six species established in streams. The success or failure of introductions of stream species appeared to be a function of the ability of a species to survive the fluctuating, highly seasonal, flow regime. The present mixture of native and exotic species has not formed stable fish assemblages but it seems likely that four habitat-associated assemblages will develop. The overall effect of the successful species introductions has been to assemble a group of species, with some exceptions, that are native to and occur together in many California streams. The assemblages now forming are similar to those found in other California streams. The assemblage characterized by squawfish and suckers is likely to be resistant to invasion, in the absence of human caused habitat modifications.

Brown, L.R.; Moyle, P.B.

1997-01-01

431

Subepicardial endothelial cells invade the embryonic ventricle wall to form coronary arteries  

PubMed Central

Coronary arteries bring blood flow to the heart muscle. Understanding the developmental program of the coronary arteries provides insights into the treatment of coronary artery diseases. Multiple sources have been described as contributing to coronary arteries including the proepicardium, sinus venosus (SV), and endocardium. However, the developmental origins of coronary vessels are still under intense study. We have produced a new genetic tool for studying coronary development, an AplnCreER mouse line, which expresses an inducible Cre recombinase specifically in developing coronary vessels. Quantitative analysis of coronary development and timed induction of AplnCreER fate tracing showed that the progenies of subepicardial endothelial cells (ECs) both invade the compact myocardium to form coronary arteries and remain on the surface to produce veins. We found that these subepicardial ECs are the major sources of intramyocardial coronary vessels in the developing heart. In vitro explant assays indicate that the majority of these subepicardial ECs arise from endocardium of the SV and atrium, but not from ventricular endocardium. Clonal analysis of Apln-positive cells indicates that a single subepicardial EC contributes equally to both coronary arteries and veins. Collectively, these data suggested that subepicardial ECs are the major source of intramyocardial coronary arteries in the ventricle wall, and that coronary arteries and veins have a common origin in the developing heart. PMID:23797856

Tian, Xueying; Hu, Tianyuan; Zhang, Hui; He, Lingjuan; Huang, Xiuzhen; Liu, Qiaozhen; Yu, Wei; He, Liang; Yang, Zhongzhou; Zhang, Zhen; Zhong, Tao P; Yang, Xiao; Yang, Zhen; Yan, Yan; Baldini, Antonio; Sun, Yunfu; Lu, Jie; Schwartz, Robert J; Evans, Sylvia M; Gittenberger-de Groot, Adriana C; Red-Horse, Kristy; Zhou, Bin

2013-01-01

432

The responsible genes in Japanese deafness patients and clinical application using Invader assay.  

PubMed

Discovery of deafness genes has progressed but clinical application lags because of the genetic heterogeneity. To establish clinical application strategy, we reviewed the frequency and spectrum of mutations found in Japanese hearing loss patients and compared them to those in populations of European ancestry. Screening revealed that in Japanese, mutations in GJB2, SLC26A4, and CDH23, and the mitochondrial 12S rRNA are the major causes of hearing loss. Also, mutations in KCNQ4, TECTA, COCH, WFS1, CRYM, COL9A3, and KIAA1199 were found in independent autosomal dominant families. Interestingly, spectrums of GJB2, SLC26A4, and CDH23 mutations in Japanese were quite different from those in Europeans. Simultaneous screening of multiple deafness mutations based on the mutation spectrum of a corresponding population using an Invader panel revealed that approximately 30% of subjects could be diagnosed. This assay will enable us to detect deafness mutations in an efficient and practical manner in the clinical platform. We conclude that specific racial populations may have unique deafness gene epidemiologies; therefore, ethnic background should be considered when genetic testing is performed. Simultaneous examination of multiple mutations based on a population's spectrum may be appropriate and effective for detecting deafness genes, facilitating precise clinical diagnosis, appropriate counseling, and proper management. PMID:18368581

Usami, Shin-Ichi; Wagatsuma, Michio; Fukuoka, Hisakuni; Suzuki, Hiroaki; Tsukada, Keita; Nishio, Shinya; Takumi, Yutaka; Abe, Satoko

2008-04-01

433

[Photosynthetic characteristics and coenological survey of Lactuca serriola in its invaded area].  

PubMed

Lactuca serriola, a national class quarantine object, is a new invasive species in the coastal area of Southeast China. The coenological survey showed that because of its big individual, L. serriola could easily form dominant population in its invaded area, and its main accompany species were Conyza canadensis, C. bonarinisis, Bidentis bipinnata, Oenothera laciniata, Ipomoea hederacea, Setaria viridis, Daucus carota, Xanthium sibiricum, Erigeron annuus, L. indica, Humulus scandens, Solanum nigrum and Aster sublatus. The measurements with LCA-4 portable photosynthesis and transpiration system (ADC, England) revealed that the net photosynthetic rate of L. serriola was as high as 21.22 +/- 0.45 micromol CO2 x m(-2) x s(-1), being slightly lower than that of E. annuus and C. bonarinisis, similar to that of C. canadensis, and higher than that of Chenopodium album, Plantago virginica and L. indica. Based on the photosynthesis-light response equation, the theoretic light compensation point of L. serriola was 37.58 micromol m(-2) x s(-1), its theoretic light saturation point was 1 480 micromol x m(-2) x s(-1), and theoretic maximal net photosynthetic rate was 20.81 micromol CO2 x m(-2) x s(-1). A distinct "noon break" phenomenon was observed in L. serriola photosynthesis, which might result from the high stomatal resistance against high light intensity and temperature. The main factors affecting the net photosynthetic rate of L. serriola were leaf photosynthetic active radiation, stomatal conductance, and leaf transpiration rate. PMID:17330472

Guo, Shui-Liang; Fang, Fang; Ni, Liping; Chen, Wanlin; Shi, Laidi

2006-12-01

434

Detection and genetic diversity of a heliothine invader (Lepidoptera: Noctuidae) from north and northeast of Brazil.  

PubMed

The cotton bollworm, Helicoverpa armigera (Hübner), was recently introduced in Brazil. During the 2012-2013 harvest, producers reported reduced yields up to 35% on major crops. The economic losses reached US$ 1 billion only in western Bahia, triggering a phytosanitary crisis. The deficiencies in existing taxonomic keys to deal with the morphologically indistinct larvae of H. armigera and the native Helicoverpa zea (Boddie) constrained the detection of new incursions of this heliothine invader. This study explored the identity of heliothine larvae that were found infesting soybean- and corn-growing areas from Roraima state, northern Brazil, through sequences of the mitochondrial cytochrome c oxidase subunit I gene. The inter- and intraspecies sequence variations of DNA barcodes in H. armigera and H. zea were analyzed. The genetic diversity and population structure of the specimens from Roraima and two populations from Piauí and Bahia states, northeastern Brazil, were assessed by adding the cytochrome c oxidase subunit II gene to the analysis. Owing to the lack of studies on genetic introgression for the two species, the suitability of using three different nuclear genes to distinguish the two species was also investigated. The results showed strong evidence that the heliothine larvae from north and northeast of Brazil are conspecific with H. armigera, suggesting that this invasive moth has already crossed the Amazon basin. Surveys in the north of South America should start as soon as possible to monitor the entry or spread of this moth in the Caribbean, Central America, and the United States. PMID:25026655

Mastrangelo, T; Paulo, D F; Bergamo, L W; Morais, E G F; Silva, M; Bezerra-Silva, G; Azeredo-Espin, A M L

2014-06-01

435

Early observations on an emerging Great Lakes invader Hemimysis anomala in Lake Ontario  

USGS Publications Warehouse

Hemimysis anomala, a Ponto-Caspian littoral mysid, is an emerging Great Lakes invader that was discovered in Lakes Michigan and Ontario in 2006. Similar to the native mysid Mysis diluviana, Hemimysis exhibits a diel vertical migration pattern but generally inhabits shallower and warmer waters than M. diluviana. Because basic information on the distribution, habitat use, and biology of Hemimysis in the Great Lakes is scarce, the potential for food web disruption by Hemimysis cannot easily be predicted. Preliminary observations indicate widespread invasion of Hemimysis in Lake Ontario. In this study, we confirm the presence of Hemimysis at sites spanning the northern and southern shores of Lake Ontario and the presence of the individuals during winter months. In one horizontal tow in November 2007, over 26,000 individuals were collected with a length range of 4.4 to 9.0. mm and an average caloric density of 611. cal/g wet weight. The most effective methods for sampling Hemimysis were horizontal tows with either a zooplankton net in the water column or a benthic sled near the lake bottom. Although more quantitative data on the life history and distribution of this species is necessary, our preliminary observations support the prediction that the potential for Hemimysis to impact the nearshore food web in Lake Ontario appears high.

Walsh, Maureen G.; Lantry, Brian F.; Boscarino, Brent; Bowen, Kelly; Gerlofsma, Jocelyn; Schaner, Ted; Back, Richard; Questel, Jennifer; Smythe, A. Garry; Cap, Roberta; Goehle, Michael; Young, Bryan; Chalupnicki, Marc; Johnson, James H.; McKenna, James E.

2010-01-01

436

Reproductive Plasticity in Freshwater Invader: From Long-Term Sperm Storage to Parthenogenesis  

PubMed Central

Orconectes limosus, a North American crayfish species, is one of the most important aquatic invaders in European inland waters. Despite more than 120 years occurrence in Europe and intense research, there are still gaps in knowledge of its life history and ecology. Investigation into O. limosus invasive success requires identifying the mechanisms that enabled them to establish dense and widespread populations from small initial numbers without observable limitation by an introduction bottleneck. In part, O. limosus success may lie in its ability to reproduce by facultative parthenogenesis. Moreover, there are possible other mating scenarios, because of two mating seasons (autumn and spring) in O. limosus. This work investigated the effect of four reproductive scenarios (autumn mating only, spring mating only, autumn and spring mating, and without mating) on the reproductive success of O. limosus. Females successfully reproduced in all tested mating regimes using parthenogenesis as well as log term sperm storage. This reproductive plasticity likely facilitates the overwhelming success of O. limosus spread and establishment in new localities. It can explain the spread of O. limosus from the initial introduction of 90 specimens to most of continental Europe and Great Britain. These conclusions imply a serious threat, not only for autochthonous European astacofauna, but for other aquatic organisms as well as entire ecosystems. PMID:24204886

Bu?i?, Miloš; Kouba, Antonín; Kozák, Pavel

2013-01-01

437

Host-plant dependent population genetics of the invading weevil Hypera postica.  

PubMed

Population genetics of invading pests can be informative for understanding their ecology. In this study, we investigated population genetics of the invasive alfalfa weevil Hypera postica in Fukuoka Prefecture, Japan. We analyzed mitochondrial tRNALeu-COII, nuclear EF-1? gene fragments, and Wolbachia infection in relation to three leguminous host plants: Vicia angustifolia, Vicia villosa, and a new host Astragalus sinicus cultivated as a honey source and green manure crop. A parsimony network generated from mitochondrial gene sequences uncovered two major haplotypic groups, Western and Egyptian. In contrast to reported Wolbachia infection of the Western strain in the United States, none of our analyzed individuals were infected. The absence of Wolbachia may contribute to the stable coexistence of mitochondrial strains through inter-strain reproductive compatibility. Hypera postica genetic variants for the mitochondrial and nuclear genes were associated neither with host plant species nor with two geographic regions (Hisayama and Kama) within Fukuoka. Mitochondrial haplogroups were incongruent with nuclear genetic variants. Genetic diversity at the nuclear locus was the highest for the populations feeding on V. angustifolia. The nuclear data for A. sinicus-feeding populations indicated past sudden population growth and extended Bayesian skyline plot analysis based on the mitochondrial and nuclear data showed that the growth of A. sinicus-feeding population took place within the past 1000 years. These results suggest a shorter history of A. sinicus as a host plant compared with V. angustifolia and a recent rapid growth of H. postica population using the new host A. sinicus. PMID:25336385

Iwase, S-I; Nakahira, K; Tuda, M; Kagoshima, K; Takagi, M

2015-02-01

438

Alien Roadside Species More Easily Invade Alpine than Lowland Plant Communities in a Subarctic Mountain Ecosystem  

PubMed Central

Effects of roads on plant communities are not well known in cold-climate mountain ecosystems, where road building and development are expected to increase in future decades. Knowledge of the sensitivity of mountain plant communities to disturbance by roads is however important for future conservation purposes. We investigate the effects of roads on species richness and composition, including the plant strategies that are most affected, along three elevational gradients in a subarctic mountain ecosystem. We also examine whether mountain roads promote the introduction and invasion of alien plant species from the lowlands to the alpine zone. Observations of plant community composition were made together with abiotic, biotic and anthropogenic factors in 60 T-shaped transects. Alpine plant communities reacted differently to road disturbances than their lowland counterparts. On high elevations, the roadside species composition was more similar to that of the local natural communities. Less competitive and ruderal species were present at high compared with lower elevation roadsides. While the effects of roads thus seem to be mitigated in the alpine environment for plant species in general, mountain plant communities are more invasible than lowland communities. More precisely, relatively more alien species present in the roadside were found to invade into the surrounding natural community at high compared to low elevations. We conclude that effects of roads and introduction of alien species in lowlands cannot simply be extrapolated to the alpine and subarctic environment. PMID:24586947

Lembrechts, Jonas J.; Milbau, Ann; Nijs, Ivan

2014-01-01

439

Mercury bioaccumulation in forage fish communities invaded by rainbow smelt (Osmerus mordax).  

PubMed

We compared total mercury concentrations ([Hg]) among 6 forage fish species in 25 central Canadian lakes and related [Hg] to adjusted-delta15N (an index of trophic position), delta13C, growth rate, and a suite of environmental variables. Growth rates were also compared among species and related to environmental variables. We found that rainbow smelt (Osmerus mordax), a recent invader in many of these lakes, had intermediate [Hg] and growth rates relative to other species. Forage fish growth rates differed significantly among species and were related to latitude (inverse relationship) and lake conductivity (positive relationship). Mercury concentrations also differed significantly among species and the strongest predictors were growth rate and lake conductivity; [Hg] was significantly and negatively related to both. Adjusted-delta15N explained very little variation in [Hg] and was significant only when the analysis was restricted to biotic variables. These results indicate that biomagnification may not be observed at fine scales of trophic differentiation and that rainbow smelt are unlikely to cause post-invasion [Hg] increases in most predatory fish species. PMID:16568754

Swanson, Heidi K; Johnston, Thomas A; Schindler, David W; Bodaly, R Andrew; Whittle, D Michael

2006-03-01

440

An Archaeal Immune System Can Detect Multiple Protospacer Adjacent Motifs (PAMs) to Target Invader DNA*  

PubMed Central

The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated (Cas) system provides adaptive and heritable immunity against foreign genetic elements in most archaea and many bacteria. Although this system is widespread and diverse with many subtypes, only a few species have been investigated to elucidate the precise mechanisms for the defense of viruses or plasmids. Approximately 90% of all sequenced archaea encode CRISPR/Cas systems, but their molecular details have so far only been examined in three archaeal species: Sulfolobus solfataricus, Sulfolobus islandicus, and Pyrococcus furiosus. Here, we analyzed the CRISPR/Cas system of Haloferax volcanii using a plasmid-based invader assay. Haloferax encodes a type I-B CRISPR/Cas system with eight Cas proteins and three CRISPR loci for which the identity of protospacer adjacent motifs (PAMs) was unknown until now. We identified six different PAM sequences that are required upstream of the protospacer to permit target DNA recognition. This is only the second archaeon for which PAM sequences have been determined, and the first CRISPR group with such a high number of PAM sequences. Cells could survive the plasmid challenge if their CRISPR/Cas system was altered or defective, e.g. by deletion of the cas gene cassette. Experimental PAM data were supplemented with bioinformatics data on Haloferax and Haloquadratum. PMID:22767603

Fischer, Susan; Maier, Lisa-Katharina; Stoll, Britta; Brendel, Jutta; Fischer, Eike; Pfeiffer, Friedhelm; Dyall-Smith, Mike; Marchfelder, Anita

2012-01-01

441

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

Code of Federal Regulations, 2012 CFR

...Eastern, Western, and Venezuelan, Killed Virus. 113.207 Section 113.207 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.207...

2012-01-01

442

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

Code of Federal Regulations, 2013 CFR

...Eastern, Western, and Venezuelan, Killed Virus. 113.207 Section 113.207 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.207...

2013-01-01

443

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

Code of Federal Regulations, 2014 CFR

...Eastern, Western, and Venezuelan, Killed Virus. 113.207 Section 113.207 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.207...

2014-01-01

444

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

Code of Federal Regulations, 2011 CFR

...Eastern, Western, and Venezuelan, Killed Virus. 113.207 Section 113.207 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.207...

2011-01-01

445

Landscape Associations of Road-killed Virginia Opossums (Didelphis virginiana) in Central Massachusetts  

E-print Network

Landscape Associations of Road-killed Virginia Opossums (Didelphis virginiana) in Central (Didelphis virginiana) in central Massachusetts. Volunteers noted road- killed opossums on their daily. The Virginia opossum (Didelphis virginiana) is broadly distributed throughout southern New England and Ontario

Schweik, Charles M.

446

Geometric properties of stationary and axisymmetric Killing horizons  

NASA Astrophysics Data System (ADS)

We study some geometric properties of Killing horizons in four-dimensional stationary and axisymmetric space-times with an electromagnetic field and a cosmological constant. Using a (1 +1 +2 ) space-time split, we construct relations between the space-time Riemann tensor components and the components of the Riemann tensor corresponding to the horizon surface. The Einstein equations allow to derive the space-time scalar curvature invariants—Kretschmann, Chern-Pontryagin, and Euler—on the two-dimensional spacelike horizon surface. The derived relations generalize the relations known for Killing horizons of static and axisymmetric four-dimensional space-times. We also present the generalization of Hartle's curvature formula.

Shoom, Andrey A.

2015-01-01

447

Secondary Kill Effect of Deltamethrin on Triatoma infestans  

PubMed Central

Control of the Chagas disease vector, Triatoma infestans, relies on the application of pyrethroid insecticides, especially deltamethrin. We performed laboratory studies to determine whether a T. infestans nymph that comes into contact with a deltamethrin-treated surface horizontally transfers the insecticide to subsequent triatomines. We found that a triatomine that walks on a deltamethrin-treated surface for a short period of time has the ability to transport the insecticide in concentrations sufficient to kill other triatomines with which it comes into contact. The effect was limited to high-density environments, and mortality as a result of secondary exposure was greater among second-instar nymphs compared with fifth-instar nymphs. Our results suggest that deltamethrin could be killing triatomines through both direct and indirect contact, although it remains unclear whether the phenomenon occurs in natural conditions. PMID:21845956

MALONEY, KATHLEEN M.; ANCCA-JUAREZ, JENNY; SALAZAR, RENZO; BORRINI-MAYORI, KATTY; PAMO-TITO, DANITZA; KEATING, JOSEPH A.; LEVY, MICHAEL Z.

2012-01-01

448

Development of a whole killed feline leukemia virus vaccine.  

PubMed

A whole killed FeLV vaccine was developed. By use of a chromatography method of purification and concentration, the resulting vaccine has been shown to be significantly lower in bovine serum albumin and total protein contents than were the same ingredients in the starting materials. The virus was inactivated or killed as an essential part of the vaccine development process. Vaccination trials with the vaccine without use of adjuvants indicated appreciable virus-neutralizing serum titer (greater than or equal to 1:10) in 107 of 110 vaccinated cats. Of 43 cats vaccinated and subsequently challenge exposed with virulent FeLV, only 2 developed persistent virus antigenemia (longer than 1 month), whereas 14 of 22 nonvaccinated control cats developed persistent viremia. In field tests, 2,770 cats from 6 states were vaccinated and observed. Postvaccinal reactions were not observed. PMID:1666095

York, S M; York, C J

1991-11-15

449

Inflammatory Neurodegeneration and Mechanisms of Microglial Killing of Neurons  

Microsoft Academic Search

Inflammatory neurodegeneration contributes to a wide variety of brain pathologies. A number of mechanisms by which inflammatory-activated\\u000a microglia and astrocytes kill neurons have been identified in culture. These include: (1) acute activation of the phagocyte\\u000a NADPH oxidase (PHOX) found in microglia, (2) expression of the inducible nitric oxide synthase (iNOS) in glia, and (3) microglial\\u000a phagocytosis of neurons. Activation of

Guy C. Brown; Jonas J. Neher

2010-01-01

450

Physical process first law for bifurcate Killing horizons  

Microsoft Academic Search

The physical process version of the first law for black holes states that the passage of energy and angular momentum through the horizon results in a change in area (\\/8)A=E-J, so long as this passage is quasistationary. A similar physical process first law can be derived for any bifurcate Killing horizon in any spacetime dimension d{>=}3 using much the same

Aaron J. Amsel; Donald Marolf; Amitabh Virmani

2008-01-01

451

Physical process first law for bifurcate Killing horizons  

Microsoft Academic Search

The physical process version of the first law for black holes states that the passage of energy and angular momentum through the horizon results in a change in area (kappa)\\/(8pi)DeltaA=DeltaE-OmegaDeltaJ, so long as this passage is quasistationary. A similar physical process first law can be derived for any bifurcate Killing horizon in any spacetime dimension d>=3 using much the same

Aaron J. Amsel; Donald Marolf; Amitabh Virmani

2008-01-01

452

Morphological effect of oscillating magnetic nanoparticles in killing tumor cells.  

PubMed

Forced oscillation of spherical and rod-shaped iron oxide magnetic nanoparticles (MNPs) via low-power and low-frequency alternating magnetic field (AMF) was firstly used to kill cancer cells in vitro. After being loaded by human cervical cancer cells line (HeLa) and then exposed to a 35-kHz AMF, MNPs mechanically damaged cell membranes and cytoplasm, decreasing the cell viability. It was found that the concentration and morphology of the MNPs significantly influenced the cell-killing efficiency of oscillating MNPs. In this preliminary study, when HeLa cells were pre-incubated with 100 ?g/mL rod-shaped MNPs (rMNP, length of 200?±?50 nm and diameter of 50 to 120 nm) for 20 h, MTT assay proved that the cell viability decreased by 30.9% after being exposed to AMF for 2 h, while the cell viability decreased by 11.7% if spherical MNPs (sMNP, diameter of 200?±?50 nm) were used for investigation. Furthermore, the morphological effect of MNPs on cell viability was confirmed by trypan blue assay: 39.5% rMNP-loaded cells and 15.1% sMNP-loaded cells were stained after being exposed to AMF for 2 h. It was also interesting to find that killing tumor cells at either higher (500 ?g/mL) or lower (20 ?g/mL) concentration of MNPs was less efficient than that achieved at 100 ?g/mL concentration. In conclusion, the relatively asymmetric morphological rod-shaped MNPs can kill cancer cells more effectively than spherical MNPs when being exposed to AMF by virtue of their mechanical oscillations. PMID:24872797

Cheng, Dengfeng; Li, Xiao; Zhang, Guoxin; Shi, Hongcheng

2014-01-01

453

Invisible CO2 gas killing trees at Mammoth Mountain, California  

USGS Publications Warehouse

Since 1980, scientists have monitored geologic unrest in Long Valley Caldera and at adjacent Mammoth Mountain, California. After a persistent swarm of earthquakes beneath Mammoth Mountain in 1989, earth scientists discovered that large volumes of carbon dioxide (CO2) gas were seeping from beneath this volcano. This gas is killing trees on the mountain and also can be a danger to people. The USGS continues to study the CO2 emissions to help protect the public from this invisible potential hazard.

Sorey, Michael L.; Farrar, Christopher D.; Evans, William C.; Hill, David P.; Bailey, Roy A.; Hendley, James W., II; Stauffer, Peter H.

1996-01-01

454

Red Fax, Vulpes vulpes, kills a European Beaver, Castorfiber, Kit  

Microsoft Academic Search

On 31 luly 1994, during a beaver census in Southeast Norway (58°39'N, 7°59'E), a Red Fax (Vulpes vulpes) was observed killing a European Beaver (Castor fiber) kit (see Kile and Nakken 1995). The observer was seated with binoculars about 100 meters from the lodge. At 1930 hours a kit emerged from the 10dge and started to eat Beaked Sedge (Carex

NILS B. KILE; PEITER J. NAKKEN; FRANK ROSELL; SIGURD ESPELAND

455

KILLING IN COMBAT MAY BE INDEPENDENTLY ASSOCIATED WITH SUICIDAL IDEATION  

PubMed Central

Background The United States military has lost more troops to suicide than to combat for the second year in a row and better understanding combat-related risk factors for suicide is critical. We examined the association of killing and suicide among war veterans after accounting for PTSD, depression, and substance use disorders. Methods We utilized a cross-sectional, retrospective, nationally representative sample of Vietnam veterans from the National Vietnam Veterans Readjustment Study (NVVRS). In order to perform a more in depth analysis, we utilized a subsample of these data, the NVVRS Clinical Interview Sample (CIS), which is representative of 1.3 million veterans who were eligible for the clinical interview by virtue of living in proximity to an interview site, located within 28 standard metropolitan regions throughout the United States. Results Veterans who had higher killing experiences had twice the odds of suicidal ideation, compared to those with lower or no killing experiences (OR = 1.99, 95% CI = 1.07–3.67), even after adjusting for demographic variables, PTSD, depression, substance use disorders, and adjusted combat exposure. PTSD (OR = 3.42, 95% CI = 1.09–10.73), depression (OR = 11.49, 95% CI = 2.12–62.38), and substance use disorders (OR = 3.98, 95% CI = 1.01–15.60) were each associated with higher odds of suicidal ideation. Endorsement of suicide attempts was most strongly associated with PTSD (OR = 5.52, 95% CI = 1.21–25.29). Conclusions Killing experiences are not routinely examined when assessing suicide risk. Our findings have important implications for conducting suicide risk assessments in veterans of war. Depression and Anxiety 29:918–923, 2012. PMID:22505038

Maguen, Shira; Metzler, Thomas J.; Bosch, Jeane; Marmar, Charles R.; Knight, Sara J.; Neylan, Thomas C.

2013-01-01

456

Pulpability of beetle-killed spruce. Forest Service research paper  

SciTech Connect

Infestation of the Dendroctonus rufipennis beetle has resulted in large stands of dead and dying timber on the Kenai Peninsula in Alaska. Tests were conducted to evaluate the value of beetle-killed spruce as pulpwood. The results showed that live and dead spruce wood can be pulped effectively. The two least deteriorated classes and the most deteriorated class of logs had similar characteristics when pulped; the remaining class had somewhat poorer pulpability.

Scott, G.M.; Bormett, D.W.; Sutherland, N.R.; Abubakr, S.; Lowell, E.

1996-08-01

457

New Geometry with All Killing Vectors Spanning the Poincaré Algebra  

E-print Network

The new 4D geometry whose Killing vectors span the Poincar\\'e algebra is presented and its structure is analyzed. The new geometry can be regarded as the Poincar\\'e-invariant solution of the degenerate extension of the vacuum Einstein field equations with a negative cosmological constant and provides a static cosmological space-time with a Lobachevsky space. The motion of free particles in the space-time is discussed.

Chao-Guang Huang; Yu Tian; Xiao-Ning Wu; Zhan Xu; Bin Zhou

2009-09-15

458

Surface Acoustic Waves Enhance Neutrophil Killing of Bacteria  

PubMed Central

Biofilms are structured communities of bacteria that play a major role in the pathogenicity of bacteria and are the leading cause of antibiotic resistant bacterial infections on indwelling catheters and medical prosthetic devices. Failure to resolve these biofilm infections may necessitate the surgical removal of the prosthetic device which can be debilitating and costly. Recent studies have shown that application of surface acoustic waves to catheter surfaces can reduce the incidence of infections by a mechanism that has not yet been clarified. We report here the effects of surface acoustic waves (SAW) on the capacity of human neutrophils to eradicate S. epidermidis bacteria in a planktonic state and within biofilms. Utilizing a novel fibrin gel system that mimics a tissue-like environment, we show that SAW, at an intensity of 0.3 mW/cm2, significantly enhances human neutrophil killing of S. epidermidis in a planktonic state and within biofilms by enhancing human neutrophil chemotaxis in response to chemoattractants. In addition, we show that the integrin CD18 plays a significant role in the killing enhancement observed in applying SAW. We propose from out data that this integrin may serve as mechanoreceptor for surface acoustic waves enhancing neutrophil chemotaxis and killing of bacteria. PMID:23936303

Loike, John D.; Plitt, Anna; Kothari, Komal; Zumeris, Jona; Budhu, Sadna; Kavalus, Kaitlyn; Ray, Yonatan; Jacob, Harold

2013-01-01

459

Sorafenib and HDAC inhibitors synergize to kill CNS tumor cells  

PubMed Central

The present studies were designed to determine whether the multi-kinase inhibitor sorafenib (Nexavar) interacted with histone deacetylase inhibitors to kill glioblastoma and medulloblastoma cells. In a dose-dependent fashion sorafenib lethality was enhanced in multiple genetically disparate primary human glioblastoma isolates by the HDAC inhibitor sodium valproate (Depakote). Drug exposure reduced phosphorylation of p70 S6K and of mTOR. Similar data to that with valproate were also obtained using the HDAC inhibitor vorinostat (Zolinza). Sorafenib and valproate also interacted to kill medulloblastoma and PNET cell lines. Treatment with sorafenib and HDAC inhibitors radio-sensitized both GBM and medulloblastoma cell lines. Knock down of death receptor (CD95) expression protected GBM cells from the drug combination, as did overexpression of c-FLIP-s, BCL-XL and dominant negative caspase 9. Knock down of PDGFR? recapitulated the effect of sorafenib in combination with HDAC inhibitors. Collectively, our data demonstrate that the combination of sorafenib and HDAC inhibitors kills through activation of the extrinsic pathway, and could represent a useful approach to treat CNS-derived tumors. PMID:22406992

Tang, Yong; Yacoub, Adly; Hamed, Hossein A.; Poklepovic, Andrew; Tye, Gary W.; Grant, Steven; Dent, Paul

2012-01-01

460

Influence of killing method on Lepidoptera DNA barcode recovery.  

PubMed

The global DNA barcoding initiative has revolutionized the field of biodiversity research. Such large-scale sequencing projects require the collection of large numbers of specimens, which need to be killed and preserved in a way that is both DNA-friendly and which will keep voucher specimens in good condition for later study. Factors such as time since collection, correct storage (exposure to free water and heat) and DNA extraction protocol are known to play a role in the success of downstream molecular applications. Limited data are available on the most efficient, DNA-friendly protocol for killing. In this study, we evaluate the quality of DNA barcode (cytochrome oxidase I) sequences amplified from DNA extracted from specimens collected using three different killing methods (ethyl acetate, cyanide and freezing). Previous studies have suggested that chemicals, such as ethyl acetate and formaldehyde, degraded DNA and as such may not be appropriate for the collection of insects for DNA-based research. All Lepidoptera collected produced DNA barcodes of good quality, and our study found no clear difference in nucleotide signal strength, probability of incorrect base calling and phylogenetic utility among the three different treatment groups. Our findings suggest that ethyl acetate, cyanide and freezing can all be used to collect specimens for DNA analysis. PMID:25229871

Willows-Munro, Sandi; Schoeman, M Corrie

2014-09-17

461

Targeted Cytotoxic Therapy Kills Persisting HIV Infected Cells During ART  

PubMed Central

Antiretroviral therapy (ART) can reduce HIV levels in plasma to undetectable levels, but rather little is known about the effects of ART outside of the peripheral blood regarding persistent virus production in tissue reservoirs. Understanding the dynamics of ART-induced reductions in viral RNA (vRNA) levels throughout the body is important for the development of strategies to eradicate infectious HIV from patients. Essential to a successful eradication therapy is a component capable of killing persisting HIV infected cells during ART. Therefore, we determined the in vivo efficacy of a targeted cytotoxic therapy to kill infected cells that persist despite long-term ART. For this purpose, we first characterized the impact of ART on HIV RNA levels in multiple organs of bone marrow-liver-thymus (BLT) humanized mice and found that antiretroviral drug penetration and activity was sufficient to reduce, but not eliminate, HIV production in each tissue tested. For targeted cytotoxic killing of these persistent vRNA+ cells, we treated BLT mice undergoing ART with an HIV-specific immunotoxin. We found that compared to ART alone, this agent profoundly depleted productively infected cells systemically. These results offer proof-of-concept that targeted cytotoxic therapies can be effective components of HIV eradication strategies. PMID:24415939

Denton, Paul W.; Long, Julie M.; Wietgrefe, Stephen W.; Sykes, Craig; Spagnuolo, Rae Ann; Snyder, Olivia D.; Perkey, Katherine; Archin, Nancie M.; Choudhary, Shailesh K.; Yang, Kuo; Hudgens, Michael G.; Pastan, Ira; Haase, Ashley T.; Kashuba, Angela D.; Berger, Edward A.; Margolis, David M.; Garcia, J. Victor

2014-01-01

462

CAN I KILL MY YOUNGER SELF? TIME TRAVEL AND THE RETRO-SUICIDE PARADOX  

E-print Network

1 CAN I KILL MY YOUNGER SELF? TIME TRAVEL AND THE RETRO-SUICIDE PARADOX Peter B. M. Vranas vranas shooting my younger self (YS); then apparently I can kill him--I can commit retro-suicide. But to kill him

Fitelson, Branden

463

Pseudomonas aeruginosa Killing of Caenorhabditis elegans Used to Identify P. aeruginosa Virulence Factors  

Microsoft Academic Search

We reported recently that the human opportunistic pathogen Pseudomonas aeruginosa strain PA14 kills Caenorhabditis elegans and that many P. aeruginosa virulence factors (genes) required for maximum virulence in mouse pathogenicity are also required for maximum killing of C. elegans. Here we report that among eight P. aeruginosa PA14 TnphoA mutants isolated that exhibited reduced killing of C. elegans, at least

Man-Wah Tan; Laurence G. Rahme; Jeffrey A. Sternberg; Ronald G. Tompkins; Frederick M. Ausubel

1999-01-01

464

Killing vector fields in three dimensions: a method to solve massive gravity field equations  

Microsoft Academic Search

Killing vector fields in three dimensions play an important role in the construction of the related spacetime geometry. In this work we show that when a three-dimensional geometry admits a Killing vector field then the Ricci tensor of the geometry is determined in terms of the Killing vector field and its scalars. In this way we can generate all products

Metin Gürses; Metin G

2010-01-01

465

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

466

Kill Tree Analysis Method and CAD Tool for Aircraft Complex System Vulnerability Assessment and Safety Design  

Microsoft Academic Search

In vulnerability assessment of aircraft complex systems subjected to traditional weapons, kill tree is used as a visual illustration of the critical components and all component redundancies. This research applies fault tree analysis method in reliability field to analyze the kill tree and determine the minimal cut sets for different kill levels, such as KK, K, A, B and C

Pei Yang; Guo Ting; Dong Qiang; Song Bifeng

2011-01-01

467

Kill rates and predation patterns of jaguars (Panthera onca) in the southern Pantanal, Brazil  

Microsoft Academic Search

Jaguars (Panthera onca) often prey on livestock, resulting in conflicts with humans. To date, kill rates and predation patterns by jaguars have not been well documented. We studied the foraging ecology of jaguars in an area with both livestock and native prey and documented kill rates, characteristics of prey killed, patterns of predation, and the influence of prey size on

Sandra M. C. Cavalcanti; Eric M. Gese

2010-01-01

468

Niche shift can impair the ability to predict invasion risk in the marine realm: an illustration using Mediterranean fish invaders.  

PubMed

Climatic niche conservatism, the tendency of species-climate associations to remain unchanged across space and time, is pivotal for forecasting the spread of invasive species and biodiversity changes. Indeed, it represents one of the key assumptions underlying species distribution models (SDMs), the main tool currently available for predicting range shifts of species. However, to date, no comprehensive assessment of niche conservatism is available for the marine realm. We use the invasion by Indo-Pacific tropical fishes into the Mediterranean Sea, the world's most invaded marine basin, to examine the conservatism of the climatic niche. We show that tropical invaders may spread far beyond their native niches and that SDMs do not predict their new distributions better than null models. Our results suggest that SDMs may underestimate the potential spread of invasive species and call for prudence in employing these models in order to forecast species invasion and their response to environmental change. PMID:25626355

Parravicini, Valeriano; Azzurro, Ernesto; Kulbicki, Michel; Belmaker, Jonathan

2015-03-01

469

CRISPR immunity relies on the consecutive binding and degradation of negatively supercoiled invader DNA by Cascade and Cas3  

Microsoft Academic Search

The prokaryotic CRISPR\\/Cas immune system is based on genomic loci that contain incorporated sequence tags from viruses and plasmids. Using small guide RNA molecules, these sequences act as a memory to reject returning invaders. Both the Cascade ribonucleoprotein complex and the Cas3 nuclease\\/helicase are required for CRISPR interference in Escherichia coli, but it is unknown how natural target DNA molecules

E. R. Westra; P. B. G. Erp; S. P. Wong; T. Künne; C. L. C. Seegers; S. Bollen; M. M. Jore; Vos de W. M; R. T. Dame; Vries de R; S. J. J. Brouns; Oost van der J

2012-01-01

470

How bad are invaders in coastal waters? The case of the American slipper limpet Crepidula fornicata in western Europe  

Microsoft Academic Search

Introduced species are assumed to exert a variety of negative ecological effects in their new environments. However, rigid\\u000a studies on such effects are still rare. Using a case study we exemplify pitfalls and obstacles for research on ecological\\u000a effects of invaders and highlight the need for a concise framework. The suspension feeding gastropod Crepidula fornicata was accidentally introduced with American

David W. Thieltges; Matthias Strasser; Karsten Reise

2006-01-01

471

A non-PCR-based Invader ® assay quantitatively detects single-copy genes in complex plant genomes  

Microsoft Academic Search

An accurate determination of gene copy number is critical to the success of a molecular breeding program involving both transgenic\\u000a and non-transgenic plants. In this paper, we have described the application of a non-PCR-based technology, Invader®*, for determination of gene copy number and zygosity in plants. A biplex assay format detected both a target gene and an endogenous\\u000a reference gene

Manju Gupta; Wilas Nirunsuksiri; Greg Schulenberg; Thomas Hartl; Stephen Novak; Jill Bryan; Nathan Vanopdorp; James Bing; Steve Thompson

2008-01-01

472

Listeria monocytogenes efficiently invades Caco-2 cells after low-temperature storage in broth and on deli meat.  

PubMed

The objective of this study was to investigate how various growth conditions influence the virulence of Listeria monocytogenes monitored by its ability to invade the epithelial cell lines Caco-2 and INT-407. The growth conditions examined were modified atmosphere-packaged deli meat and brain heart infusion broth (BHI) with and without salt. Five strains of L. monocytogenes were selected to investigate their invasiveness and all strains invaded Caco-2 cells at higher levels than INT-407 cells. Further, the clinical strains (3443 and 3734) were more invasive (p < 0.05) than the strains isolated from meat and food-processing environments (3008, 3126, and 4140) after grown in BHI at 30 degrees C. This attenuation could not be ascribed to a defective Internalin A as all strains encoded an intact inlA gene. To determine the influence of food products on virulence, the ability of L. monocytogenes to invade Caco-2 cells was compared after growth on a fermented sausage and on cured cooked ham to that of bacteria grown in BHI broth supplemented with salt. Samples were stored under chilling conditions for up to 4 weeks. The results showed no difference (p > 0.05) in invasiveness after 7 days at 10 degrees C in BHI broth or on sausage, whereas a slight increase (p < 0.05) was observed after incubation on ham for 2 and 4 weeks compared to that in BHI broth. Most importantly, our results show that L. monocytogenes efficiently invade Caco-2 cells even after 4 weeks of storage at chilled temperature. This is highly relevant for safety assessment of this organism in food as these conditions reflect storage of ready-to-eat food products in domestic refrigerators. PMID:20443727

Larsen, Marianne Halberg; Koch, Anette Granly; Ingmer, Hanne

2010-09-01

473

Responses to invasion and invader removal differ between native and exotic plant groups in a coastal dune.  

PubMed

The spread of exotic, invasive species is a global phenomenon that is recognized as a major source of environmental change. Although many studies have addressed the effects of exotic plants on the communities they invade, few have quantified the effects of invader removal on plant communities, or considered the degree to which different plant groups vary in response to invasion and invader removal. We evaluated the effects of an exotic succulent, iceplant (Carpobrotus edulis), on a coastal dune plant community in northern California, as well as the community responses to its removal. To assess possible mechanisms by which iceplant affects other plants, we also evaluated its above- and belowground influences on the germination and growth of a dominant exotic annual grass, Bromus diandrus. We found that iceplant invasion was associated with reduced native plant cover as well as increased cover and density of some exotic plants-especially exotic annual grasses. However, iceplant removal did not necessarily lead to a reversal of these effects: removal increased the cover and density of both native and exotic species. We also found that B. diandrus grown in iceplant patches, or in soil where iceplant had been removed, had poorer germination and growth than B. diandrus grown in soil not influenced by iceplant. This suggests that the influence of iceplant on this dune plant community occurs, at least in part, due to belowground effects, and that these effects remain after iceplant has been removed. Our study demonstrates the importance of considering how exotic invasive plants affect not only native species, but also co-occurring exotic taxa. It also shows that combining observational studies with removal experiments can lead to important insights into the influence of invaders and the mechanisms of their effects. PMID:23839266

Magnoli, Susan M; Kleinhesselink, Andrew R; Cushman, J Hall

2013-12-01

474

Phenological niches and the future of invaded ecosystems with climate change  

PubMed Central

In recent years, research in invasion biology has focused increasing attention on understanding the role of phenology in shaping plant invasions. Multiple studies have found non-native species that tend to flower distinctly early or late in the growing season, advance more with warming or have shifted earlier with climate change compared with native species. This growing body of literature has focused on patterns of phenological differences, but there is a need now for mechanistic studies of how phenology contributes to invasions. To do this, however, requires understanding how phenology fits within complex functional trait relationships. Towards this goal, we review recent literature linking phenology with other functional traits, and discuss the role of phenology in mediating how plants experience disturbance and stress—via climate, herbivory and competition—across the growing season. Because climate change may alter the timing and severity of stress and disturbance in many systems, it could provide novel opportunities for invasion—depending upon the dominant climate controller of the system, the projected climate change, and the traits of native and non-native species. Based on our current understanding of plant phenological and growth strategies—especially rapid growing, early-flowering species versus later-flowering species that make slower-return investments in growth—we project optimal periods for invasions across three distinct systems under current climate change scenarios. Research on plant invasions and phenology within this predictive framework would provide a more rigorous test of what drives invader success, while at the same time testing basic plant ecological theory. Additionally, extensions could provide the basis to model how ecosystem processes may shift in the future with continued climate change. PMID:24876295

Wolkovich, Elizabeth M.; Cleland, Elsa E.

2014-01-01

475

Next-Generation Invaders? Hotspots for Naturalised Sleeper Weeds in Australia under Future Climates  

PubMed Central

Naturalised, but not yet invasive plants, pose a nascent threat to biodiversity. As climate regimes continue to change, it is likely that a new suite of invaders will emerge from the established pool of naturalised plants. Pre-emptive management of locations that may be most suitable for a large number of potentially invasive plants will help to target monitoring, and is vital for effective control. We used species distribution models (SDM) and invasion-hotspot analysis to determine where in Australia suitable habitat may occur for 292 naturalised plants. SDMs were built in MaxEnt using both climate and soil variables for current baseline conditions. Modelled relationships were projected onto two Representative Concentration Pathways for future climates (RCP 4.5 and 8.5), based on seven global climate models, for two time periods (2035, 2065). Model outputs for each of the 292 species were then aggregated into single ‘hotspot’ maps at two scales: continental, and for each of Australia’s 37 ecoregions. Across Australia, areas in the south-east and south-west corners of the continent were identified as potential hotspots for naturalised plants under current and future climates. These regions provided suitable habitat for 288 and 239 species respectively under baseline climates. The areal extent of the continental hotspot was projected to decrease by 8.8% under climates for 2035, and by a further 5.2% by 2065. A similar pattern of hotspot contraction under future climates was seen for the majority of ecoregions examined. However, two ecoregions - Tasmanian temperate forests and Australian Alps montane grasslands - showed increases in the areal extent of hotspots of >45% under climate scenarios for 2065. The alpine ecoregion also had an increase in the number of naturalised plant species with abiotically suitable habitat under future climate scenarios, indicating that this area may be particularly vulnerable to future incursions by naturalised plants. PMID:24386353

Roger, Erin; Hughes, Lesley; Downey, Paul O.; Leishman, Michelle R.

2013-01-01

476

Black locust-Successful invader of a wide range of soil conditions.  

PubMed

Black locust (Robinia pseudoacacia, BL), a species native to North America, has successfully invaded many types of habitats over the world. This study provides an overall assessment of BL soil conditions to determine the range of physical-chemical soil properties it can tolerate. 511 BL stands (for the soil types) and 33 permanent plots (for the soil chemistry) were studied in the Czech Republic. Relationships among different environmental variables (physical-chemical soil properties, vegetation characteristics and habitat conditions) were investigated and variables with the highest effect on species composition were detected. The results were compared with data in the literature for other parts of the secondary and native distributions of this species. This assessment showed that BL is able to tolerate extremely diverse soil physical-chemical conditions, from extremely acid to strongly alkaline, and from medium to highly base saturated soils with a gradient of different subsurface stoniness. Soil nitrate, N mineralization and nitrification rates also varied considerably and the concentrations of exchangeable phosphorus and ammonium were consistently low. N mineralization rate, incubated inorganic nitrogen and nitrates were positively correlated with base saturation and cation exchange capacity. The most common soil types were young soils (Cambisols, Leptosols, Arenosols, and coarsely textured Fluvisols). BL seems to be limited by water supply and soil aeration and prefers well aerated and drained soils, and tolerates desiccation but avoids compact soils and areas where the soils are frequently waterlogged. On steep slopes, BL was less vigorous, stunted and less competitive. By contrast, the tallest BL trees were found on sandy soils in a flat landscape. Number and share of nitrophytes in the herb layer were positively related to basic bedrock, soil reaction and N-NO3/N ratio. Soil reaction was determined as the most important environmental characteristic explaining the variability in BL species composition in the Czech Republic. PMID:25461033

Vítková, Michaela; Tonika, Jaroslav; Müllerová, Jana

2015-02-01

477

The Role of Palliative Radiosurgery When Cancer Invades the Cavernous Sinus  

SciTech Connect

Purpose: Involvement of the cavernous sinus by direct invasion from skull base cancer or from metastatic spread of cancers is a challenging problem. We evaluated the role of stereotactic radiosurgery (SRS) in the treatment of patients who developed cavernous sinus metastases or direct invasion. Methods and Materials: We retrospectively reviewed the data from 37 patients who had cavernous sinus metastases or had cavernous sinus invasion from adjacent skull base cancers and who underwent SRS between 1992 and 2006 at University of Pittsburgh Medical Center. The median patient age was 57.8 years. Previous adjuvant management included fractionated radiotherapy in 8, chemotherapy in 16, and both radiotherapy and chemotherapy in 5. The primary sites of metastases or invasion were nasopharyngeal carcinoma (n = 7), parotid gland carcinoma (n = 7), and metastases from systemic cancer (n = 23). The median target volume was 6.3 cm{sup 3} (range, 0.3-33.6), and the median margin dose was 14 Gy (range, 12-20). Results: At a mean of 12.9 months (range, 0.8-63.9), 32 patients had died and 5 were living. The overall survival rate after SRS was 36.6% and 19.4% at 1 and 2 years, respectively. Progression-free survival was related to a greater marginal dose. After SRS, 12 (35.3%) of 34 patients with neurologic symptoms exhibited improvement. SRS early after diagnosis was significantly associated with improvement of cranial nerve dysfunction. Conclusion: SRS is a minimally invasive palliative option for patients whose cancer has invaded the cavernous sinus. The benefits for cranial nerve deficits are best when SRS is performed early.

Kano, Hideyuki; Niranjan, Ajay; Kondziolka, Douglas [Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Center for Image-Guided Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Flickinger, John C. [Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Department of Radiation Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Lunsford, L. Dade [Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States); Center for Image-Guided Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, PA (United States)], E-mail: lunsfordld@upmc.edu

2009-03-01

478

Nowhere to invade: Rumex crispus and Typha latifolia projected to disappear under future climate scenarios.  

PubMed

Future climate change has been predicted to affect the potential distribution of plant species. However, only few studies have addressed how invasive species may respond to future climate change despite the known effects of plant species invasion on nutrient cycles, ecosystem functions, and agricultural yields. In this study, we predicted the potential distributions of two invasive species, Rumex crispus and Typha latifolia, under current and future (2050) climatic conditions. Future climate scenarios considered in our study include A1B, A2, A2A, B1, and B2A. We found that these two species will lose their habitat under the A1B, A2, A2A, and B1 scenarios. Their distributions will be maintained under future climatic conditions related to B2A scenarios, but the total area will be less than 10% of that under the current climatic condition. We also investigated variations of the most influential climatic variables that are likely to cause habitat loss of the two species. Our results demonstrate that rising mean annual temperature, variations of the coldest quarter, and precipitation of the coldest quarter are the main factors contributing to habitat loss of R. crispus. For T. latifolia, the main factors are rising mean annual temperature, variations in temperature of the coldest quarter, mean annual precipitation, and precipitation of the coldest quarter. These results demonstrate that the warmer and wetter climatic conditions of the coldest season (or month) will be mainly responsible for habitat loss of R. crispus and T. latifolia in the future. We also discuss uncertainties related to our study (and similar studies) and suggest that particular attention should be directed toward the manner in which invasive species cope with rapid climate changes because evolutionary change can be rapid for species that invade new areas. PMID:23923020

Xu, Zhonglin; Feng, Zhaodong; Yang, Jianjun; Zheng, Jianghua; Zhang, Fang

2013-01-01

479

Peripheral Lung Adenocarcinomas With KRAS Mutations Are More Likely to Invade Visceral Pleura.  

PubMed

Context .- Kirsten-RAS (KRAS) mutations play an important role in the carcinogenesis of a subset of lung adenocarcinomas and are associated with poorer prognosis. Objective .- To investigate the relationship of KRAS mutation status to the histologic subtype of adenocarcinoma according to the recent classification, patient demographics, tumor size, predominant histologic subtype, nodal status, and visceral pleural invasion, in an attempt to uncover the reason for the worse prognosis associated with KRAS mutation. Design .- A total of 187 consecutive resected lung adenocarcinomas from our institution from 2008 to 2011 that were diagnosed according to the new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification and screened for KRAS mutations were included in the study. Results .- A total of 32% of the adenocarcinomas harbored the KRAS mutation. The median age in the KRAS mutation group was 69 years (range, 43-86 years), and male to female ratio was 1:2.3. The proportion of heavy smokers was significantly higher in tumors with KRAS mutation compared with wild type (83% versus 62%; P = .01). A total of 27% of tumors with KRAS mutation had pleural invasion versus 11% of tumors without KRAS mutation (P = .009). A total of 59 tumor samples were positive for KRAS mutation (25 for G12C, 14 for G12A, 8 for G12V, 7 for G12D, 3 for G12S, and 1 for G12T), and only 3 tumors harbored codon 13 mutations (G13C). Two tumors had double mutations. Conclusions .- KRAS mutations are more common in heavy smokers, and lung adenocarcinomas with KRAS mutation are more likely to invade the visceral pleura. Increased frequency of visceral pleural invasion may explain in part the worse prognosis associated with KRAS mutations. PMID:24694341

Raparia, Kirtee; Villa, Celina; Raj, Rishi; Cagle, Philip T

2015-02-01

480

Quantifying levels of biological invasion: towards the objective classification of invaded and invasible ecosystems  

PubMed Central

Biological invasions are a global phenomenon that threatens biodiversity, and few, if any, ecosystems are free from alien species. The outcome of human-mediated introductions is affected by the invasiveness of species and invasibility of ecosystems, but research has primarily focused on defining, characterizing and identifying invasive species; ecosystem invasibility has received much less attention. A prerequisite for characterizing invasibility is the ability to compare levels of invasion across ecosystems. In this paper, we aim to identify the best way to quantify the level of invasion by nonnative animals and plants by reviewing the advantages and disadvantages of different metrics. We explore how interpretation and choice of these measures can depend on the objective of a study or management intervention. Based on our review, we recommend two invasion indices and illustrate their use by applying them to two case studies. Relative alien species richness and relative alien species abundance indicate the contribution that alien species make to a community. They are easy to measure, can be applied to various taxa, are independent of scale and are comparable across regions and ecosystems, and historical data are often available. The relationship between relative alien richness and abundance can indicate the presence of dominant alien species and the trajectory of invasion over time, and can highlight ecosystems and sites that are heavily invaded or especially susceptible to invasion. Splitting species into functional groups and examining invasion patterns of transformer species may be particularly instructive for gauging effects of alien invasion on ecosystem structure and function. Establishing standard, transparent ways to define and quantify invasion level will facilitate meaningful comparisons among studies, ecosystem types and regions. It is essential for progress in ecology and will help guide ecosystem restoration and management.

Catford, Jane A; Vesk, Peter A; Richardson, David M; Pyšek, Petr

2012-01-01

481

Atlantic salmon populations invaded by farmed escapees: quantifying genetic introgression with a Bayesian approach and SNPs  

PubMed Central

Background Many native Atlantic salmon populations have been invaded by domesticated escapees for three decades or longer. However, thus far, the cumulative level of gene-flow that has occurred from farmed to wild salmon has not been reported for any native Atlantic salmon population. The aim of the present study was to investigate temporal genetic stability in native populations, and, quantify gene-flow from farmed salmon that caused genetic changes where they were observed. This was achieved by genotyping historical and contemporary samples from 20 populations covering all of Norway with recently identified single nucleotide polymorphism markers that are collectively diagnostic for farmed and wild salmon. These analyses were combined with analysis of farmed salmon and implementation of Approximate Bayesian computation based simulations. Results Five of the populations displayed statistically significant temporal genetic changes. All five of these populations became more similar to a pool of farmed fish with time, strongly suggesting introgression of farmed fish as the primary cause. The remaining 15 populations displayed weak or non-significant temporal genetic changes. Estimated introgression of farmed fish ranged from 2-47% per population using approximate Bayesian computation. Thus, some populations exhibited high degrees of farmed salmon introgression while others were more or less unaffected. The observed frequency of escapees in each population was moderately correlated with estimated introgression per population R2?=?0.47 P?

2013-01-01

482

Augmentation of Epithelial Resistance to Invading Bacteria by Using mRNA Transfections  

PubMed Central

To protect against invading bacteria, oral epithelial cells appear to use two effector antimicrobial peptides (AMPs): calprotectin (S100A8-S100A9 heterodimer [S100A8/A9]) in the cytosol and cathelicidin antimicrobial protein (CAMP) in endosomes. We sought to learn whether innate immunity might be augmented benignly to increase resistance against invasive bacteria. Epithelial cells were transiently transfected with mRNA constructs containing either the CAMP, S100A8, and S100A9 open reading frames, A8-IRES-A9 (fusion sequence), or A8-nIRES-A9 (fusion with native internal ribosome entry site [IRES] sequence). CAMP, S100A8, and S100A9 protein levels generally peaked between 16 and 44 h after mRNA transfection, depending on the construct; CAMP was processed to LL-37 over time. Following transfection with the respective mRNAs, CAMP and S100A8/A9 each independently increased resistance of epithelial cells to invasion by Listeria and Salmonella for up to 48 h; tandem S100A8/A9 constructs were also effective. Cotransfection to express S100A8/A9 and CAMP together augmented resistance, but synergy was not seen. Independent of the new proteins produced, transfection reduced cell viability after 48 h by 20%, with only 2% attributable to apoptosis. Taken together, these results suggest that epithelial cell resistance to invasive pathogens can be augmented by transient transfection of antimicrobial mRNAs into epithelial cells. PMID:23940207

Zou, Xianqiong; Sorenson, Brent S.; Ross, Karen F.

2013-01-01

483

High Invasive Pollen Transfer, Yet Low Deposition on Native Stigmas in a Carpobrotus-invaded Community  

PubMed Central

Background and Aims Invasive plants are potential agents of disruption in plant–pollinator interactions. They may affect pollinator visitation rates to native plants and modify the plant–pollinator interaction network. However, there is little information about the extent to which invasive pollen is incorporated into the pollination network and about the rates of invasive pollen deposition on the stigmas of native plants. Methods The degree of pollinator sharing between the invasive plant Carpobrotus affine acinaciformis and the main co-flowering native plants was tested in a Mediterranean coastal shrubland. Pollen loads were identified from the bodies of the ten most common pollinator species and stigmatic pollen deposition in the five most common native plant species. Key Results It was found that pollinators visited Carpobrotus extensively. Seventy-three per cent of pollinator specimens collected on native plants carried Carpobrotus pollen. On average 23 % of the pollen on the bodies of pollinators visiting native plants was Carpobrotus. However, most of the pollen found on the body of pollinators belonged to the species on which they were collected. Similarly, most pollen on native plant stigmas was conspecific. Invasive pollen was present on native plant stigmas, but in low quantity. Conclusions Carpobrotus is highly integrated in the pollen transport network. However, the plant-pollination network in the invaded community seems to be sufficiently robust to withstand the impacts of the presence of alien pollen on native plant pollination, as shown by the low levels of heterospecific pollen deposition on native stigmas. Several mechanisms are discussed for the low invasive pollen deposition on native stigmas. PMID:18593688