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Sample records for aerobic anoxygenic phototrophic

  1. Method for quantification of aerobic anoxygenic phototrophic bacteria

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yao; JIAO Nianzhi

    2004-01-01

    Accurate quantification of aerobic anoxygenic phototrophic bacteria (AAPB) is of crucial importance for estimation of the role of AAPB in the carbon cycling in marine ecosystems. The normally used method "epifiuorescence microscope-infrared photography (EFM-IRP)"is, however, subject to positive errors introduced by mistaking cyanobacteria as AAPB due to the visibility of cyanobacteria under infrared photographic conditions for AAPB. This error could be up to 30% in the coast of the East China Sea. Such bias should be avoided by either subtracting cyanobacteira from the total infrared counts or using a fiowcytometer equipped with specific detectors for discrimination between cyanobacteria and AAPB.

  2. Ecology of aerobic anoxygenic phototrophs in aquatic environments.

    Science.gov (United States)

    Koblížek, Michal

    2015-11-01

    Recognition of the environmental role of photoheterotrophic bacteria has been one of the main themes of aquatic microbiology over the last 15 years. Aside from cyanobacteria and proteorhodopsin-containing bacteria, aerobic anoxygenic phototrophic (AAP) bacteria are the third most numerous group of phototrophic prokaryotes in the ocean. This functional group represents a diverse assembly of species which taxonomically belong to various subgroups of Alpha-, Beta- and Gammaproteobacteria. AAP bacteria are facultative photoheterotrophs which use bacteriochlorophyll-containing reaction centers to harvest light energy. The light-derived energy increases their bacterial growth efficiency, which provides a competitive advantage over heterotrophic species. Thanks to their enzymatic machinery AAP bacteria are active, rapidly growing organisms which contribute significantly to the recycling of organic matter. This chapter summarizes the current knowledge of the ecology of AAP bacteria in aquatic environments, implying their specific role in the microbial loop.

  3. Aerobic anoxygenic phototrophic bacteria and their roles in marine ecosystems

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Aerobic anoxygenic phototrophic bacteria (AAPB) are characterized by the following physiological and ecological features. A mother AAPB cell can unusually divide into 3 daughter cells and looks like a "Y" during the division. AAPB cells sometimes adhere together forming a free-floating population. Most of the known AAPB species are obligately aerobic. Bacteriochlorophyll a (BChl a) is the only photosynthetic pigment in AAPB, and the number of BChl a molecules in an AAPB cell is much less than that in an anaerobic phototrophic bacterial cell, while the accessorial pigments carotenoids in AAPB are abundant in concentration and diverse in species. In addition to the common magnesium containing BChl a, a zinc-containing BChla was also seen in AAPB. AAPB have light harvesting complexⅠbut usually lack light harvesting complexⅡ. Although AAPB featur in photosynthesis, their growth is not necessarily light- dependent. There is a mechanism controlling the photosynthesis approach. AAPB are widely distributed in marine environments especially in oligotrophic oceans accounting for a substantial portion of the total biomass and playing a unique role in the cycle of carbon and other biogenic elements. Besides the contribution to primary production, AAPB also have great potentials in bioremediation of polluted environments. Studies on AAPB would be of great value in understanding the evolution of photosynthesis and the structure and function of marine ecosystems.

  4. A new extreme environment for aerobic anoxygenic phototrophs: biological soil crusts.

    Science.gov (United States)

    Csotonyi, Julius T; Swiderski, Jolantha; Stackebrandt, Erko; Yurkov, Vladimir

    2010-01-01

    Biological soil crusts improve the health of arid or semiarid soils by enhancing water content, nutrient relations and mechanical stability, facilitated largely by phototrophic microorganisms. Until recently, only oxygenic phototrophs were known from soil crusts. A recent study has demonstrated the presence of aerobic representatives of Earth's second major photosynthetic clade, the evolutionarily basal anoxygenic phototrophs. Three Canadian soil crust communities yielded pink and orange aerobic anoxygenic phototrophic strains possessing the light-harvesting pigment bacteriochlorophyll a. At relative abundances of 0.1-5.9% of the cultivable bacterial community, they were comparable in density to aerobic phototrophs in other documented habitats. 16S rDNA sequence analysis revealed the isolates to be related to Methylobacterium, Belnapia, Muricoccus and Sphingomonas. This result adds a new type of harsh habitat, dry soil environments, to the environments known to support aerobic anoxygenic phototrophs.

  5. A new environment for aerobic anoxygenic phototrophic bacteria: biological soil crusts.

    Science.gov (United States)

    Csotonyi, Julius T; Swiderski, Jolantha; Stackebrandt, Erko; Yurkov, Vladimir

    2010-10-01

    Phototrophic microorganisms are critical to the carbon cycling and productivity of biological soil crusts, which enhance water content, nutrient relations and mechanical stability of arid soils. Only oxygen-producing phototrophs, including cyanobacteria and algae, are known from soil crusts, but Earth's second major branch of photosynthetic organisms, the evolutionarily earlier anoxygenic phototrophs, is unreported. We announce the discovery of aerobic anoxygenic phototrophs in three Canadian soil crust communities. We found in a culture-based study that they comprised 0.1-5.9% of the cultivable bacterial community in moss-, lichen- and cyanobacteria-dominated crust from sand dunes and sandy soils. Comparable in density to aerobic phototrophs in other habitats, the bacteriochlorophyll a-possessing pink and orange isolates were related to species of Methylobacterium (99.0-99.5%), Belnapia (97.4-98.8%), Muricoccus (94.4%) and Sphingomonas (96.6-98.5%), based on 16S rRNA gene sequences. Our results demonstrate that proteobacterial anoxygenic phototrophs may be found in dry soil environments, implying desiccation resistance as yet unreported for this group. By utilizing sunlight for part of their energy needs, aerobic phototrophs can accelerate organic carbon cycling in nutrient-poor arid soils. Their effects will be especially important as global climate change enhances soil erosion and consequent nutrient loss.

  6. Phylogenetically Diverse Aerobic Anoxygenic Phototrophic Bacteria Isolated from Epilithic Biofilms in Tama River, Japan

    Science.gov (United States)

    Hirose, Setsuko; Matsuura, Katsumi; Haruta, Shin

    2016-01-01

    The diversity of aerobic anoxygenic phototrophic (AAP) bacteria in freshwater environments, particularly in rivers, has not been examined in as much detail as in ocean environments. In the present study, we investigated the phylogenetic and physiological diversities of AAP bacteria in biofilms that developed on submerged stones in a freshwater river using culture methods. The biofilms collected were homogenized and inoculated on solid media and incubated aerobically in the dark. Sixty-eight red-, pink-, yellow-, orange-, or brown-colored colonies were isolated, and, of these, 28 isolates contained the photosynthetic pigment, bacteriochlorophyll (BChl) a. Phylogenetic analyses based on 16S rRNA gene sequences showed that the isolates were classified into 14 groups in 8 operational taxonomic units (OTUs) and distributed in the orders Rhodospirillales, Rhodobacterales, and Sphingomonadales of Alphaproteobacteria and in Betaproteobacteria. Physiological analyses confirmed that none of the representative isolates from any of the groups grew under anaerobic phototrophic conditions. Seven isolates in 4 OTUs showed a 16S rRNA gene sequence identity of 98.0% or less with any established species, suggesting the presence of previously undescribed species of AAP bacteria. Six isolates in 2 other OTUs had the closest relatives, which have not been reported to be AAP bacteria. Physiological comparisons among the isolates revealed differences in preferences for nutrient concentrations, BChl contents, and light-harvesting proteins. These results suggest that diverse and previously unknown AAP bacteria inhabit river biofilms. PMID:27453124

  7. Diversity and Distribution of Freshwater Aerobic Anoxygenic Phototrophic Bacteria across a Wide Latitudinal Gradient

    Science.gov (United States)

    Ferrera, Isabel; Sarmento, Hugo; Priscu, John C.; Chiuchiolo, Amy; González, José M.; Grossart, Hans-Peter

    2017-01-01

    Aerobic anoxygenic phototrophs (AAPs) have been shown to exist in numerous marine and brackish environments where they are hypothesized to play important ecological roles. Despite their potential significance, the study of freshwater AAPs is in its infancy and limited to local investigations. Here, we explore the occurrence, diversity and distribution of AAPs in lakes covering a wide latitudinal gradient: Mongolian and German lakes located in temperate regions of Eurasia, tropical Great East African lakes, and polar permanently ice-covered Antarctic lakes. Our results show a widespread distribution of AAPs in lakes with contrasting environmental conditions and confirm that this group is composed of different members of the Alpha- and Betaproteobacteria. While latitude does not seem to strongly influence AAP abundance, clear patterns of community structure and composition along geographic regions were observed as indicated by a strong macro-geographical signal in the taxonomical composition of AAPs. Overall, our results suggest that the distribution patterns of freshwater AAPs are likely driven by a combination of small-scale environmental conditions (specific of each lake and region) and large-scale geographic factors (climatic regions across a latitudinal gradient). PMID:28275369

  8. Aerobic Anoxygenic Phototrophic Bacteria in the Mid-Atlantic Bight and the North Pacific Gyre. Revised

    Science.gov (United States)

    Cottrell, Matthew T.; Mannino, Antonio; Kirchman, David L.

    2005-01-01

    The abundance of aerobic anoxygenic phototrophic (AM) bacteria, cyanobacteria and heterotrophs was examined in the Mid-Atlantic Bight and the central North Pacific gyre using infrared fluorescence microscopy coupled with image analysis and flow cytometry. AAP bacteria comprised 5% to 16% of total prokaryotes in the Atlantic but only 5% or less in the Pacific. In the Atlantic, AAP bacterial abundance was as much as 2-fold higher than Prochlorococcus and 10-folder higher than Synechococcus. In contrast, Prochlorococcus outnumbered AAP bacteria 5- to 50-fold in the Pacific. In both oceans, subsurface abundance maxima occurred within the photic zone, and AAP bacteria were least abundant below the 1% light depth. Concentrations of bacteriochlorophyll a (BChl a) were low (approx.1%) compared to chlorophyll a. Although the BChl a content of AAP bacteria per cell was typically 20- to 250-fold lower than the divinyl-chlorophyll a content of Prochlorococcus, in shelf break water the pigment content of AAP bacteria approached that of Prochlorococcus. The abundance of AAP bacteria rivaled some groups of strictly heterotrophic bacteria and was often higher than the abundance of known AAP genera (Erythrobacter and Roseobacter spp.). The distribution of AAP bacteria in the water column, which was similar in the Atlantic and the Pacific, was consistent with phototrophy.

  9. Abundance and genetic diversity of aerobic anoxygenic phototrophic bacteria of coastal regions of the pacific ocean.

    Science.gov (United States)

    Ritchie, Anna E; Johnson, Zackary I

    2012-04-01

    Aerobic anoxygenic phototrophic (AAP) bacteria are photoheterotrophic microbes that are found in a broad range of aquatic environments. Although potentially significant to the microbial ecology and biogeochemistry of marine ecosystems, their abundance and genetic diversity and the environmental variables that regulate these properties are poorly understood. Using samples along nearshore/offshore transects from five disparate islands in the Pacific Ocean (Oahu, Molokai, Futuna, Aniwa, and Lord Howe) and off California, we show that AAP bacteria, as quantified by the pufM gene biomarker, are most abundant near shore and in areas with high chlorophyll or Synechococcus abundance. These AAP bacterial populations are genetically diverse, with most members belonging to the alpha- or gammaproteobacterial groups and with subclades that are associated with specific environmental variables. The genetic diversity of AAP bacteria is structured along the nearshore/offshore transects in relation to environmental variables, and uncultured pufM gene libraries suggest that nearshore communities are distinct from those offshore. AAP bacterial communities are also genetically distinct between islands, such that the stations that are most distantly separated are the most genetically distinct. Together, these results demonstrate that environmental variables regulate both the abundance and diversity of AAP bacteria but that endemism may also be a contributing factor in structuring these communities.

  10. Photosynthetic characteristics of marine aerobic anoxygenic phototrophic bacteria Roseobacter and Erythrobacter strains.

    Science.gov (United States)

    Sato-Takabe, Yuki; Hamasaki, Koji; Suzuki, Koji

    2012-05-01

    A coastal Roseobacter strain of marine aerobic anoxygenic phototrophic bacteria (AAnPB) was isolated and phylogenetically determined. The strain OBYS 0001 was characterized by its physiological and biochemical properties with reference to the Erythrobacter longus type strain NBRC 14126. When grown in batch cultures, the growth curves of the both strains were similar. Cellular bacteriochlorophyll a concentrations of the strains reached the maxima in the stationary growth conditions. In vivo fluorescence excitation/optical density spectra between 470 and 600 nm for OBYS 0001 represented higher values than NBRC 14126. Variable fluorescence measurements revealed that the functional absorption cross section (σ) of the bacterial photosynthetic complexes for OBYS 0001 was significantly higher than that for NBRC 14126 under green excitation. These results suggest that Roseobacter can capture green light more efficiently than Erythrobacter for photosynthesis. The photochemical quantum efficiencies (F (v)/F (m)) of the bacterial photosynthetic complexes for OBYS 0001 were consistently lower than those for NBRC 14126. A relationship between the growth rate and F (v)/F (m) was significant for OBYS 0001, but that was not found for NBRC 14126. These results suggested that F (v)/F (m) for AAnPB could not be used as a proxy of the growth rate which is consistent with their mostly heterotrophic characters.

  11. Environmental control of growth and BChl a expression in an aerobic anoxygenic phototrophic bacterium,Erythrobacter longus (DSMZ6997)

    Institute of Scientific and Technical Information of China (English)

    LI Qiang; JIAO Nianzhi; PENG Zaiqing

    2006-01-01

    Aerobic anoxygenic phototrophic bacteria (AAPB), which form a unique functional group of heterotrophic bacteria, have the ability to utilize light energy. The impact of carbon source and light intensity on the growth and bacteriochlorophyll a (BChl a) expression of a typical strain of AAPB, Erythrobacter longus strain DSMZ6997 was examined during batch culture and continuous culture. The results showed that the expression of BChl a in DSMZ6997 was regulated by both carbon-source and light conditions, and was stimulated by low availability of carbon but inhibited by light to a certain extent at 300 lx and completely at 1 500 lx. In contrast, cell abundance, and even cell size of this strain, was substantially enhanced under light/dark cycle cultivation conditions over dark conditions, indicating the promotion of growth by light. These results led to the conclusion that utilization of light through BChl a helps AAPB to survive under carbon stress, while light at high intensity is harmful to the synthesis of BChl a in AAPB.

  12. Diversity of cultivated and metabolically active aerobic anoxygenic phototrophic bacteria along an oligotrophic gradient in the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    C. Jeanthon

    2011-07-01

    Full Text Available Aerobic anoxygenic phototrophic (AAP bacteria play significant roles in the bacterioplankton productivity and biogeochemical cycles of the surface ocean. In this study, we applied both cultivation and mRNA-based molecular methods to explore the diversity of AAP bacteria along an oligotrophic gradient in the Mediterranean Sea in early summer 2008. Colony-forming units obtained on three different agar media were screened for the production of bacteriochlorophyll-a (BChl-a, the light-harvesting pigment of AAP bacteria. BChl-a-containing colonies represented a low part of the cultivable fraction. In total, 54 AAP strains were isolated and the phylogenetic analyses based on their 16S rRNA and pufM genes showed that they were all affiliated to the Alphaproteobacteria. The most frequently isolated strains belonged to Citromicrobium bathyomarinum, and Erythrobacter and Roseovarius species. Most other isolates were related to species not reported to produce BChl-a and/or may represent novel taxa. Direct extraction of RNA from seawater samples enabled the analysis of the expression of pufM, the gene coding for the M subunit of the reaction centre complex of aerobic anoxygenic photosynthesis. Clone libraries of pufM gene transcripts revealed that most phylotypes were highly similar to sequences previously recovered from the Mediterranean Sea and a large majority (~94 % was affiliated to the Gammaproteobacteria. The most abundantly detected phylotypes occurred in the western and eastern Mediterranean basins. However, some were exclusively detected in the eastern basin, reflecting the highest diversity of pufM transcripts observed in this ultra-oligotrophic region. To our knowledge, this is the first study to document extensively the diversity of AAP isolates and to unveil the active AAP community in an oligotrophic marine environment. By pointing out the discrepancies

  13. Comparison of growth rates of aerobic anoxygenic phototrophic bacteria and other bacterioplankton groups in coastal Mediterranean waters.

    Science.gov (United States)

    Ferrera, Isabel; Gasol, Josep M; Sebastián, Marta; Hojerová, Eva; Koblízek, Michal

    2011-11-01

    Growth is one of the basic attributes of any living organism. Surprisingly, the growth rates of marine bacterioplankton are only poorly known. Current data suggest that marine bacteria grow relatively slowly, having generation times of several days. However, some bacterial groups, such as the aerobic anoxygenic phototrophic (AAP) bacteria, have been shown to grow much faster. Two manipulation experiments, in which grazing, viruses, and resource competition were reduced, were conducted in the coastal Mediterranean Sea (Blanes Bay Microbial Observatory). The growth rates of AAP bacteria and of several important phylogenetic groups (the Bacteroidetes, the alphaproteobacterial groups Roseobacter and SAR11, and the Gammaproteobacteria group and its subgroups the Alteromonadaceae and the NOR5/OM60 clade) were calculated from changes in cell numbers in the manipulation treatments. In addition, we examined the role that top-down (mortality due to grazers and viruses) and bottom-up (resource availability) factors play in determining the growth rates of these groups. Manipulations resulted in an increase of the growth rates of all groups studied, but its extent differed largely among the individual treatments and among the different groups. Interestingly, higher growth rates were found for the AAP bacteria (up to 3.71 day⁻¹) and for the Alteromonadaceae (up to 5.44 day⁻¹), in spite of the fact that these bacterial groups represented only a very low percentage of the total prokaryotic community. In contrast, the SAR11 clade, which was the most abundant group, was the slower grower in all treatments. Our results show that, in general, the least abundant groups exhibited the highest rates, whereas the most abundant groups were those growing more slowly, indicating that some minor groups, such the AAP bacteria, very likely contribute much more to the recycling of organic matter in the ocean than what their abundances alone would predict.

  14. Remotely Detectable Biosignatures of Anoxygenic Phototrophs

    Science.gov (United States)

    Parenteau, M. N.; Kiang, N. Y.; Blankenship, R. E.; Sanromá, E.; Palle Bago, E.; Hoehler, T. M.; Pierson, B. K.

    2014-12-01

    Many astrobiological/exobiological studies have been directed at searching for evidence of life on planetary bodies within our solar system, but the search for life does not have to be restricted to our stellar neighborhood. The field of exoplanet research has grown rapidly over the last several years. Studies have moved beyond detection to assessing the habitability and biosignatures of these worlds. The biosignatures considered thus far focus on biogenic gases and planetary surface features, such as the light reflected from the surface of plants to generate the "red edge" of vegetation. Much work has focused on detecting biosignatures of higher life forms (vegetation) on exoplanets. However, land plants only appeared on the Earth 450 million years ago, and required a long path of photosynthetic evolution. There is a dearth of studies examining how light might interact with much simpler, more evolutionarily ancient pigmented communities, such as photosynthetic microbes. These anoxygenic phototrophs, which have inhabited Earth for nearly 80% of its history, may dominate exoplanets at a similar stage of evolution as the Archean or Paleoproterozoic Earth. Similar to the remotely detectable "red edge" of chlorophyll a - containing vegetation, we measured the reflectance spectra of pure cultures and environmental samples of purple sulfur, purple non-sulfur, heliobacteria, green sulfur, and green non-sulfur anoxygenic phototrophs. We observed an increase in reflectivity just past the absorption maximum for the bacteriochlorophyll pigments. Since this reflectance feature is shifted into the NIR compared to that of the red edge of vegetation, we're calling this the "NIR edge" of anoxygenic phototrophs. The bacteriochlorophyll pigments are particularly well suited to absorb the far-red and near-infrared radiation emitted by M dwarf stars, the most common type of star in our galaxy. Therefore these phototrophs serve as model organisms for photosynthesis adapted to

  15. Extremely 'vanadiphilic' multiply metal-resistant and halophilic aerobic anoxygenic phototrophs, strains EG13 and EG8, from hypersaline springs in Canada.

    Science.gov (United States)

    Csotonyi, J T; Maltman, C; Swiderski, J; Stackebrandt, E; Yurkov, V

    2015-01-01

    Two pinkish peach-colored strains of obligately aerobic phototrophic bacteria, EG13 and EG8, were isolated from a saline spring effluent stream in west central Manitoba, Canada. The strains possessed bacteriochlorophyll a incorporated into a typical purple bacterial light-harvesting complex 1 (870 nm) and reaction center (801 nm). Analysis of 16S rRNA gene sequences indicated 100% identity among the isolates and 99% similarity to Roseovarius tolerans EL-172(T). The strains were physiologically well adapted to high salinity (0-22%), fluctuating pH (7-12) and temperature (7-40 °C) of the exposed hypersaline stream of East German Creek. EG8 and EG13 were also highly resistant to the toxic metal(loid) oxyanions tellurite, selenite and metavanadate (≥1000 μg/ml each). Most intriguingly, growth and pigment production of EG13 on glutamate minimal medium was stimulated by 1000-10000 μg/ml of sodium metavanadate compared to metal-free conditions. Phylogenetic analysis and phenotypic properties such as pigment composition and morphology indicate close relatedness to Roseovarius genus.

  16. Complete genome sequence of the filamentous anoxygenic phototrophic bacterium Chloroflexus aurantiacus

    Directory of Open Access Journals (Sweden)

    Larimer Frank W

    2011-06-01

    Full Text Available Abstract Background Chloroflexus aurantiacus is a thermophilic filamentous anoxygenic phototrophic (FAP bacterium, and can grow phototrophically under anaerobic conditions or chemotrophically under aerobic and dark conditions. According to 16S rRNA analysis, Chloroflexi species are the earliest branching bacteria capable of photosynthesis, and Cfl. aurantiacus has been long regarded as a key organism to resolve the obscurity of the origin and early evolution of photosynthesis. Cfl. aurantiacus contains a chimeric photosystem that comprises some characters of green sulfur bacteria and purple photosynthetic bacteria, and also has some unique electron transport proteins compared to other photosynthetic bacteria. Methods The complete genomic sequence of Cfl. aurantiacus has been determined, analyzed and compared to the genomes of other photosynthetic bacteria. Results Abundant genomic evidence suggests that there have been numerous gene adaptations/replacements in Cfl. aurantiacus to facilitate life under both anaerobic and aerobic conditions, including duplicate genes and gene clusters for the alternative complex III (ACIII, auracyanin and NADH:quinone oxidoreductase; and several aerobic/anaerobic enzyme pairs in central carbon metabolism and tetrapyrroles and nucleic acids biosynthesis. Overall, genomic information is consistent with a high tolerance for oxygen that has been reported in the growth of Cfl. aurantiacus. Genes for the chimeric photosystem, photosynthetic electron transport chain, the 3-hydroxypropionate autotrophic carbon fixation cycle, CO2-anaplerotic pathways, glyoxylate cycle, and sulfur reduction pathway are present. The central carbon metabolism and sulfur assimilation pathways in Cfl. aurantiacus are discussed. Some features of the Cfl. aurantiacus genome are compared with those of the Roseiflexus castenholzii genome. Roseiflexus castenholzii is a recently characterized FAP bacterium and phylogenetically closely related to Cfl

  17. COMPETITION BETWEEN ANOXYGENIC PHOTOTROPHIC BACTERIA AND COLORLESS SULFUR BACTERIA IN A MICROBIAL MAT

    NARCIS (Netherlands)

    VISSCHER, PT; VANDENENDE, FP; SCHAUB, BEM; VANGEMERDEN, H

    1992-01-01

    The populations of chemolithoautotrophic (colorless) sulfur bacteria and anoxygenic phototrophic bacteria were enumerated in a marine microbial mat. The highest population densities were found in the 0-5 mm layer of the mat: 2.0 X 10(9) cells CM-3 sediment, and 4.0 X 10(7) cells cm-3 sediment for th

  18. Filamentous anoxygenic phototrophic bacteria from cyanobacterial mats of Alla hot springs (Barguzin Valley, Russia).

    Science.gov (United States)

    Gaisin, Vasil A; Kalashnikov, Alexander M; Sukhacheva, Marina V; Namsaraev, Zorigto B; Barhutova, Darima D; Gorlenko, Vladimir M; Kuznetsov, Boris B

    2015-11-01

    Alkaline hydrotherms of the Baikal rift zone are unique systems to study the diversity of thermophilic bacteria. In this study, we present data on the phototrophic bacterial community of cyanobacterial mats from the alkaline Alla hot spring. Using a clonal analysis approach, this study evaluated the species diversity, the proportion of oxygenic and anoxygenic phototrophs and their distribution between various areas of the spring. Novel group-specific PCR primers were designed and applied to detect representatives of the Chloroflexus and Roseiflexus genera in mat samples. For the first time, the presence of Roseiflexus-like bacteria was detected in the Baikal rift zone.

  19. Competition for inorganic carbon between oxygenic and anoxygenic phototrophs in a hypersaline microbial mat, Guerrero Negro, Mexico

    DEFF Research Database (Denmark)

    Finke, Niko; Hoehler, Tori M.; Polerecky, Lubos

    2013-01-01

    While most oxygenic phototrophs harvest light only in the visible range (400-700 nm, VIS), anoxygenic phototrophs can harvest near infrared light (> 700 nm, NIR). To study interactions between the photosynthetic guilds we used microsensors to measure oxygen and gross oxygenic photosynthesis (gOP)...

  20. Competition for inorganic carbon between oxygenic and anoxygenic phototrophs in a hypersaline microbial mat, Guerrero Negro, Mexico.

    Science.gov (United States)

    Finke, Niko; Hoehler, Tori M; Polerecky, Lubos; Buehring, Benjamin; Thamdrup, Bo

    2013-05-01

    While most oxygenic phototrophs harvest light only in the visible range (400-700 nm, VIS), anoxygenic phototrophs can harvest near infrared light (> 700 nm, NIR). To study interactions between the photosynthetic guilds we used microsensors to measure oxygen and gross oxygenic photosynthesis (gOP) in a hypersaline microbial mat under full (VIS + NIR) and VIS illumination. Under normal dissolved inorganic carbon (DIC) concentrations (2 mM), volumetric rates of gOP were reduced up to 65% and areal rates by 16-31% at full compared with VIS illumination. This effect was enhanced (reduction up to 100% in volumetric, 50% in areal rates of gOP) when DIC was lowered to 1 mM, but diminished at 10 mM DIC or lowered pH. In conclusion, under full-light illumination anoxygenic phototrophs are able to reduce the activity of oxygenic phototrophs by efficiently competing for inorganic carbon within the highly oxygenated layer. Anoxygenic photosynthesis, calculated from the difference in gOP under full and VIS illumination, represented between 10% and 40% of the C-fixation. The DIC depletion in the euphotic zone as well as the significant C-fixation by anoxygenic phototrophs in the oxic layer influences the carbon isotopic composition of the mat, which needs to be taken into account when interpreting isotopic biosignals in geological records.

  1. Vertical distribution and characterization of aerobic phototrophic bacteria at the Juan de Fuca Ridge in the Pacific Ocean.

    Science.gov (United States)

    Rathgeber, Christopher; Lince, Michael T; Alric, Jean; Lang, Andrew S; Humphrey, Elaine; Blankenship, Robert E; Verméglio, André; Plumley, F Gerald; Van Dover, Cindy L; Beatty, J Thomas; Yurkov, Vladimir

    2008-09-01

    The vertical distribution of culturable anoxygenic phototrophic bacteria was investigated at five sites at or near the Juan de Fuca Ridge in the Pacific Ocean. Twelve similar strains of obligately aerobic phototrophic bacteria were isolated in pure culture, from depths ranging from 500 to 2,379 m below the surface. These strains appear morphologically, physiologically, biochemically, and phylogenetically similar to Citromicrobium bathyomarinum strain JF-1, a bacterium previously isolated from hydrothermal vent plume waters. Only one aerobic phototrophic strain was isolated from surface waters. This strain is morphologically and physiologically distinct from the strains isolated at deeper sampling locations, and phylogenetic analysis indicates that it is most closely related to the genus Erythrobacter. Phototrophs were cultivated from three water casts taken above vents but not from two casts taken away from active vent sites. No culturable anaerobic anoxygenic phototrophs were detected. The photosynthetic apparatus was investigated in strain JF-1 and contains light-harvesting I and reaction center complexes, which are functional under aerobic conditions.

  2. An alphaproteobacterium capable of both aerobic and anaerobic anoxygenic photosynthesis but incapable of photoautotrophy: Charonomicrobium ambiphototrophicum, gen. nov., sp. nov.

    Science.gov (United States)

    Csotonyi, J T; Stackebrandt, E; Swiderski, J; Schumann, P; Yurkov, V

    2011-03-01

    A facultatively aerobic deep brown coccoid to ovoid bacterium, strain EG17(T), was isolated from a saline effluent stream in the NaCl-dominated brine spring system known as East German Creek in the province of Manitoba, Canada. The strain produced BChl a incorporated into a functional reaction center and two light-harvesting complexes with absorption peaks at 802, 850, and 879 nm. EG17(T) is the first reported anoxygenic phototroph capable of photoheterotrophic growth under both oxic and anoxic conditions. It yielded proportionally the greatest aerobic photosynthetic biomass under oligotrophic conditions. The results of 16S rRNA gene sequence comparisons revealed that EG17(T) was related most closely to the aerobic anoxygenic phototrophs Roseibacterium elongatum (98.3%) and quite distantly to both Dinoroseobacter shibae (95.2%) and Roseicyclus mahoneyensis (94.7%). The DNA G + C content was 65.6 mol%. On the basis of the unique dual aerobic/anaerobic photosynthetic capability, the distinctive spectrophotometric absorption of the photosynthetic apparatus, diagnostic physiological and biochemical traits, and the moderate phylogenetic separation between EG17(T) and its nearest relatives, it is concluded that this microorganism should be classified as a novel genus and species, Charonomicrobium ambiphototrophicum gen. nov., sp. nov., with EG17(T) as the type strain.

  3. Oxygen and sulfur isotope fractionation during sulfide oxidation by anoxygenic phototrophic bacteria

    Science.gov (United States)

    Brabec, Michelle Y.; Lyons, Timothy W.; Mandernack, Kevin W.

    2012-04-01

    Sulfide-mediated anoxygenic photosynthesis (SMAP) carried out by anaerobic phototrophic bacteria may have played an important role in sulfur cycling, formation of sulfate, and, perhaps, primary production in the Earth’s early oceans. Determination of ε34SSO4-Sulfide- and ε18OSO4-H2O values for bacterial sulfide oxidation will permit more refined interpretation of the δ34S and δ18OSO4 values measured in modern anoxic environments, such as meromictic lakes where sulfide commonly extends into the photic zone, and in the ancient rock record, particularly during periods of the Precambrian when anoxic and sulfidic (euxinic) conditions were believed to be more pervasive than today. Laboratory experiments with anaerobic purple and green sulfur phototrophs, Allochromatium vinosum and Chlorobaculum tepidum, respectively, were conducted to determine the sulfur and oxygen isotope fractionation during the oxidation of sulfide to sulfate. Replicate experiments were conducted at 25 °C for A. vinosum and 45 °C for C. tepidum, and in duplicate at three different starting oxygen isotope values for water to determine sulfate-water oxygen isotope fractionations accurately (ε18OSO4-H2O). ε18OSO4-H2O values of 5.6 ± 0.2‰ and 5.4 ± 0.1‰ were obtained for A. vinosum and C. tepidum, respectively. Temperature had no apparent effect on the ε18OSO4-H2O values. By combining all data from both cultures, an average ε18OSO4-H2O value of 5.6 ± 0.3‰ was obtained for SMAP. This value falls between those previously reported for bacterial oxidation of sphalerite and elemental sulfur (7-9‰) and abiotic and biotic oxidation of pyrite and chalcopyrite (2-4‰). Sulfur isotope fractionation between sulfide and sulfate formed by A.vinosum was negligible (0.1 ± 0.2‰) during all experiments. For C. tepidum an apparent fractionation of -2.3 ± 0.5‰ was observed during the earlier stages of oxidation based on bulk δ34S measurements of sulfate and sulfide and became smaller (-0.7

  4. Diversity of the aerobic anoxygenic phototrophy genepufM in Arctic and Antarctic coastal seawaters

    Institute of Scientific and Technical Information of China (English)

    ZENG Yinxin; DONG Peiyan; QIAO Zongyun; ZHENG Tianling

    2016-01-01

    Aerobic anoxygenic phototrophic (AAP) bacteria serve important functions in marine carbon and energy cycling because of their capability to utilize dissolved organic substrates and harvest light energy. AAP bacteria are widely distributed in marine environments, and their diversity has been examined in marine habitats. However, information about AAP bacteria at high latitudes remains insufficient to date. Therefore, this study determined the summer AAP bacterial diversity in Arctic Kongsfjorden and in the Antarctic coastal seawater of King George Island on the basis ofpufM, a gene that encodes a pigment-binding protein subunit of the reaction center complex. FourpufM clone libraries were constructed, and 674 positive clones were obtained from four investigated stations (two in Kongsfjorden and two in the Antarctic Maxwell Bay). Arctic clones were clustered within theAlphaproteobacteria, whereas Antarctic clones were classified into theAlphaproteobacteria and Betaproteobacteria classes.Rhodobacteraceae-likepufM genes dominated in all samples. In addition, sequences closely related topufM encoded on a plasmid inSulfitobacter guttiformis were predominant in both Arctic and Antarctic samples. This result indicates the transpolar or even global distribution ofpufM genes in marine environments. Meanwhile, differences between the Arctic and Antarctic sequences may prove polar endemism. These results indicate the important role ofRhodobacteraceae as AAP bacteria in bipolar coastal waters.

  5. Roseobacter-Like Bacteria in Red and Mediterranean Sea Aerobic Anoxygenic Photosynthetic Populations

    Science.gov (United States)

    Oz, Aia; Sabehi, Gazalah; Koblízek, Michal; Massana, Ramon; Béjà, Oded

    2005-01-01

    Bacteriochlorophyll a-containing aerobic anoxygenic phototrophs (AAnP) have been proposed to account for up to 11% of the total surface water microbial community and to potentially have great ecological importance in the world's oceans. Recently, environmental and genomic data based on analysis of the pufM gene identified the existence of α-proteobacteria as well as possible γ-like proteobacteria among AAnP in the Pacific Ocean. Here we report on analyses of environmental samples from the Red and Mediterranean Seas by using pufM as well as the bchX and bchL genes as molecular markers. The majority of photosynthesis genes retrieved from these seas were related to Roseobacter-like AAnP sequences. Furthermore, the sequence of a novel photosynthetic operon organization from an uncultured Roseobacter-like bacterial artificial chromosome retrieved from the Red Sea is described. The data show the presence of Roseobacter-like bacteria in Red and Mediterranean Sea AAnP populations in the seasons analyzed. PMID:15640208

  6. 玛珥湖好氧不产氧光合细菌pufM基因DNA和mRNA的定量及多样性分析%Genetic diversity and quantification of aerobic anoxygenic phototrophic bacteria in Hugangyan Maar Lake based on pufM DNA and mRNA analysis

    Institute of Scientific and Technical Information of China (English)

    陈晓洁; 曾永辉; 简纪常; 鲁义善; 吴灶和

    2012-01-01

    [Objective] Maar lake is a special type of Crater Lake.Huguangyan Maar Lake was formed about 140 k-160 k years ago, fully closed, and has not yet been affected by human activities, where abundant and novel microbial species might dwell as reported previously.Aerobic anoxygenic phototrophic bacteria (AAPB) is a functional bacterial group with long evolution history in Earth possessing unique physiological and ecological characteristics.To date, our knowledge about AAPB distribution in Maar Lake is still blank.[Methods] Here, by constructing and analyzing six clone libraries of the photosynthetic reaction center pufM gene from total DNA and RNA, respectively, with 1 m, 5 m, and 12 m water layers in Huguangyan Maar Lake, and combining quantitative Real-time PCR, we studied AAPB's distribution, phy-logenetic diversity and the proportion in the total bacteria in different water layers.The results of coverage value and rarefaction curves of six libraries showed that AAPB diversity was sampled well for the purpose of revealing the diversity of main AAPB groups in each water layer.[Results] BLAST analysis showed that pufM sequences in Maar Lake were 80%-93% similar to public sequences.Diversity index indicated that the AAPB diversity in surface and deep layers was similar, whereas diversity in the intermediate layer was lowest.In view of total RNA and DNA data, pufM RNA diversity was higher than that of DNA.Phylogenetic and statistical analysis revealed that 49.43% sequences are fell into the OTUs 21-24 which were closely related to P-proteobacteria and represent dominated AAPB groups.Quantitative PCR results showed that the percentage of AAPB in total bacteria in 1 m water layer reached a highest value of 38.06%, whereas only 0.85% and 9.54% in 5 m and 12 m, respectively.[Conclusion] Huguangyan Maar Lake is occupied by rich and diverse AAPB groups.%[目的]湖光岩玛珥湖是一类特殊的火山口湖,它完全封闭,地质年代久远,尚未受人类活动的剧烈

  7. Seeing green bacteria in a new light: genomics-enabled studies of the photosynthetic apparatus in green sulfur bacteria and filamentous anoxygenic phototrophic bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Bryant, Donald A

    2004-01-01

    Based upon their photosynthetic nature and the presence of a unique light-harvesting antenna structure, the chlorosome, the photosynthetic green bacteria are defined as a distinctive group in the Bacteria. However, members of the two taxa that comprise this group, the green sulfur bacteria...... (Chlorobi) and the filamentous anoxygenic phototrophic bacteria ("Chloroflexales"), are otherwise quite different, both physiologically and phylogenetically. This review summarizes how genome sequence information facilitated studies of the biosynthesis and function of the photosynthetic apparatus...... and carotenoid species also allow the functions of these pigments to be studied in vivo....

  8. Dynamics of the anoxygenic phototrophic community in meromictic Fayetteville Green Lake (NY) and the associated sedimentary pigment record

    Science.gov (United States)

    Meyer, K. M.; Fulton, J. M.; Hunter, S.; Macalady, J. L.; Kump, L.; Freeman, K. H.

    2012-12-01

    Photosynthetic pigments and their diagenetic products in marine sedimentary rocks hold important clues about recent and ancient variability in the Earth's surface environment. The chemical relicts of carotenoids from anoxygenic sulfur bacteria are of particular interest to geoscientists because of their potential to signal episodes of marine photic-zone euxinia such as those proposed for extended periods in the Proterozoic as well as brief intervals during the Phanerozoic. It is therefore critical to constrain the environmental and physiological factors that influence carotenoid production and preservation in modern environments. Our work in redox stratified, microbially dominated Fayetteville Green Lake (New York) has spanned the past decade and included seasonal (2005-2006) and monthly (2011) pigment monitoring in the water column, as well as a coupled pigment and nucleic acid clone library analyses from planktonic and benthic samples in 2006. Populations of photosynthetic bacteria in the water column are dynamic on monthly and annual scales. In 2011, purple sulfur bacteria (PSB) and green sulfur bacteria (GSB) were most abundant in spring and fall, respectively, responding to environmental conditions. PSB are diverse both at the chemocline and in benthic mats below oxygenated shallow waters, with different PSB species inhabiting the two environments. Okenone (from PSB) is an abundant carotenoid in both the chemocline waters and in benthic mats. GSB and their primary pigment Bchl e are also represented in and below the chemocline. However, the water column and sediments contain only trace concentrations of the GSB carotenoid isorenieratene, with concentrations relative to Bchl e being at least two orders of magnitude lower than we have observed in other meromictic lakes. Sediments deposited over the past ~550 years also reveal decadal to centennial scale variability in pigment production in the water column, possibly associated with hypothesized climatic and

  9. Isolation of aerobic anoxygenic photosynthetic bacteria from black smoker plume waters of the juan de fuca ridge in the pacific ocean.

    Science.gov (United States)

    Yurkov, V; Beatty, J T

    1998-01-01

    A strain of the aerobic anoxygenic photosynthetic bacteria was isolated from a deep-ocean hydrothermal vent plume environment. The in vivo absorption spectra of cells indicate the presence of bacteriochlorophyll a incorporated into light-harvesting complex I and a reaction center. The general morphological and physiological characteristics of this new isolate are described.

  10. Geminicoccus roseus gen. nov., sp. nov., an aerobic phototrophic Alphaproteobacterium isolated from a marine aquaculture biofilter

    DEFF Research Database (Denmark)

    Foesel, Bärbel U.; Gößner, Anita S.; Drake, Harold L.;

    2007-01-01

    A Gram-negative, strictly aerobic, diplococcoid bacterium (strain D2-3T) was isolated from the biofilter of a recirculating marine aquaculture system. Phylogenetic analysis of the 16S rRNA gene sequence of D2-3T indicated that the new organism occupied a novel lineage within the α-1 subclass...

  11. Anoxic and oxic phototrophic primary production during the Precambrian

    DEFF Research Database (Denmark)

    Ebey-Honeycutt, Christina Marie; Bjerrum, Christian J.; Canfield, Donald Eugene

    2009-01-01

    of the mixed layer often lies above the base of the photic zone . Thus, an ecosystem model for the Precambrian should reflect the net primary production (NPP) of oxygenic phototrophs in the mixed layer and anoxygenic phototrophs below (NPPox and NPPred, respectively). Satelite data and a vertically generalized...

  12. Novel acsF gene primers revealed a diverse phototrophic bacterial population, including Gemmatimonadetes, in Lake Taihu (China)

    DEFF Research Database (Denmark)

    Huang, Yili; Zeng, Yanhua; Lu, Hang;

    2016-01-01

    UNLABELLED: Anoxygenic phototrophs represent an environmentally important and phylogenetically diverse group of organisms. They harvest light using bacteriochlorophyll-containing reaction centers. Recently, a novel phototrophic bacterium, Gemmatimonas phototrophica, belonging to a rarely studied ...

  13. Sulfur metabolism in phototrophic sulfur bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Dahl, Christiane

    2008-01-01

    Phototrophic sulfur bacteria are characterized by oxidizing various inorganic sulfur compounds for use as electron donors in carbon dioxide fixation during anoxygenic photosynthetic growth. These bacteria are divided into the purple sulfur bacteria (PSB) and the green sulfur bacteria (GSB......). They utilize various combinations of sulfide, elemental sulfur, and thiosulfate and sometimes also ferrous iron and hydrogen as electron donors. This review focuses on the dissimilatory and assimilatory metabolism of inorganic sulfur compounds in these bacteria and also briefly discusses these metabolisms...... in other types of anoxygenic phototrophic bacteria. The biochemistry and genetics of sulfur compound oxidation in PSB and GSB are described in detail. A variety of enzymes catalyzing sulfur oxidation reactions have been isolated from GSB and PSB (especially Allochromatium vinosum, a representative...

  14. Phototrophic Fe(II)-oxidation in the chemocline of a ferruginous meromictic lake

    Science.gov (United States)

    Walter, Xavier A.; Picazo, Antonio; Miracle, Maria R.; Vicente, Eduardo; Camacho, Antonio; Aragno, Michel; Zopfi, Jakob

    2014-01-01

    Precambrian Banded Iron Formation (BIF) deposition was conventionally attributed to the precipitation of iron-oxides resulting from the abiotic reaction of ferrous iron (Fe(II)) with photosynthetically produced oxygen. Earliest traces of oxygen date from 2.7 Ga, thus raising questions as to what may have caused BIF precipitation before oxygenic photosynthesis evolved. The discovery of anoxygenic phototrophic bacteria thriving through the oxidation of Fe(II) has provided support for a biological origin for some BIFs, but despite reports suggesting that anoxygenic phototrophs may oxidize Fe(II) in the environment, a model ecosystem of an ancient ocean where they are demonstrably active was lacking. Here we show that anoxygenic phototrophic bacteria contribute to Fe(II) oxidation in the water column of the ferruginous sulfate-poor, meromictic lake La Cruz (Spain). We observed in-situ photoferrotrophic activity through stimulation of phototrophic carbon uptake in the presence of Fe(II), and determined light-dependent Fe(II)-oxidation by the natural chemocline microbiota. Moreover, a photoferrotrophic bacterium most closely related to Chlorobium ferrooxidans was enriched from the ferruginous water column. Our study for the first time demonstrates a direct link between anoxygenic photoferrotrophy and the anoxic precipitation of Fe(III)-oxides in a ferruginous water column, providing a plausible mechanism for the bacterial origin of BIFs before the advent of free oxygen. However, photoferrotrophs represent only a minor fraction of the anoxygenic phototrophic community with the majority apparently thriving by sulfur cycling, despite the very low sulfur content in the ferruginous chemocline of Lake La Cruz. PMID:25538702

  15. Biofilm comprising phototrophic, diazotrophic, and hydrocarbon-utilizing bacteria: a promising consortium in the bioremediation of aquatic hydrocarbon pollutants.

    Science.gov (United States)

    Al-Bader, Dhia; Kansour, Mayada K; Rayan, Rehab; Radwan, Samir S

    2013-05-01

    Biofilms harboring simultaneously anoxygenic and oxygenic phototrophic bacteria, diazotrophic bacteria, and hydrocarbon-utilizing bacteria were established on glass slides suspended in pristine and oily seawater. Via denaturing gradient gel electrophoresis analysis on PCR-amplified rRNA gene sequence fragments from the extracted DNA from biofilms, followed by band amplification, biofilm composition was determined. The biofilms contained anoxygenic phototrophs belonging to alphaproteobacteria; pico- and filamentous cyanobacteria (oxygenic phototrophs); two species of the diazotroph Azospirillum; and two hydrocarbon-utilizing gammaproteobacterial genera, Cycloclasticus and Oleibacter. The coexistence of all these microbial taxa with different physiologies in the biofilm makes the whole community nutritionally self-sufficient and adequately aerated, a condition quite suitable for the microbial biodegradation of aquatic pollutant hydrocarbons.

  16. Anoxygenic Photosynthesis Controls Oxygenic Photosynthesis in a Cyanobacterium from a Sulfidic Spring

    KAUST Repository

    Klatt, Judith M.

    2015-03-15

    Before the Earth\\'s complete oxygenation (0.58 to 0.55 billion years [Ga] ago), the photic zone of the Proterozoic oceans was probably redox stratified, with a slightly aerobic, nutrient-limited upper layer above a light-limited layer that tended toward euxinia. In such oceans, cyanobacteria capable of both oxygenic and sulfide-driven anoxygenic photosynthesis played a fundamental role in the global carbon, oxygen, and sulfur cycle. We have isolated a cyanobacterium, Pseudanabaena strain FS39, in which this versatility is still conserved, and we show that the transition between the two photosynthetic modes follows a surprisingly simple kinetic regulation controlled by this organism\\'s affinity for H2S. Specifically, oxygenic photosynthesis is performed in addition to anoxygenic photosynthesis only when H2S becomes limiting and its concentration decreases below a threshold that increases predictably with the available ambient light. The carbon-based growth rates during oxygenic and anoxygenic photosynthesis were similar. However, Pseudanabaena FS39 additionally assimilated NO3 - during anoxygenic photosynthesis. Thus, the transition between anoxygenic and oxygenic photosynthesis was accompanied by a shift of the C/N ratio of the total bulk biomass. These mechanisms offer new insights into the way in which, despite nutrient limitation in the oxic photic zone in the mid-Proterozoic oceans, versatile cyanobacteria might have promoted oxygenic photosynthesis and total primary productivity, a key step that enabled the complete oxygenation of our planet and the subsequent diversification of life.

  17. Anoxygenic photosynthesis controls oxygenic photosynthesis in a cyanobacterium from a sulfidic spring.

    Science.gov (United States)

    Klatt, Judith M; Al-Najjar, Mohammad A A; Yilmaz, Pelin; Lavik, Gaute; de Beer, Dirk; Polerecky, Lubos

    2015-03-01

    Before the Earth's complete oxygenation (0.58 to 0.55 billion years [Ga] ago), the photic zone of the Proterozoic oceans was probably redox stratified, with a slightly aerobic, nutrient-limited upper layer above a light-limited layer that tended toward euxinia. In such oceans, cyanobacteria capable of both oxygenic and sulfide-driven anoxygenic photosynthesis played a fundamental role in the global carbon, oxygen, and sulfur cycle. We have isolated a cyanobacterium, Pseudanabaena strain FS39, in which this versatility is still conserved, and we show that the transition between the two photosynthetic modes follows a surprisingly simple kinetic regulation controlled by this organism's affinity for H2S. Specifically, oxygenic photosynthesis is performed in addition to anoxygenic photosynthesis only when H2S becomes limiting and its concentration decreases below a threshold that increases predictably with the available ambient light. The carbon-based growth rates during oxygenic and anoxygenic photosynthesis were similar. However, Pseudanabaena FS39 additionally assimilated NO3 (-) during anoxygenic photosynthesis. Thus, the transition between anoxygenic and oxygenic photosynthesis was accompanied by a shift of the C/N ratio of the total bulk biomass. These mechanisms offer new insights into the way in which, despite nutrient limitation in the oxic photic zone in the mid-Proterozoic oceans, versatile cyanobacteria might have promoted oxygenic photosynthesis and total primary productivity, a key step that enabled the complete oxygenation of our planet and the subsequent diversification of life.

  18. Taxonomy of phototrophic green and purple bacteria: a review.

    Science.gov (United States)

    Pfennig, N; Trüper, H G

    1983-01-01

    The presently existing classification for the green and purple bacteria comprises physiological-ecological assemblages of phototrophic bacteria with anoxygenic photosynthesis. The taxonomic units of the different levels were based entirely on common phenotypic traits, including morphological, cytological, physiological and biochemical characteristics. Since degrees of resemblance form the basis of the grouping, this classification cannot reflect the genetic or evolutionary relatedness of these bacteria, neither among themselves nor with other bacteria. The advantage of the artificial system, however, is the use of features which can be established in most laboratories and which allow the comparison and identification of newly isolated strains with those already studied and described. The four existing families correspond to the four major recognized, ecophysiological groups, the Chlorobiaceae and Chloroflexaceae among the green bacteria, and the Chromatiaceae and Rhodospirillaceae among the purple bacteria. Our knowledge of all these groups is incomplete; this is reflected by the fact that seven new species have been described during the past three years (6th Newsletter on phot. bacteria, Trüper and Hansen, 1982). The description of the new genus and species Erythrobacter longus (Shiba and Simidu, 1982) is also interesting, as it comprises aerobic chemoorganotrophic marine bacteria which form bacteriochlorophyll a and carotenoids; however, no strains were able to grow phototrophilcally. Significant success is currently being obtained in the different approaches toward elucidating the genetic relationships within and outside of the purple and green bacteria. Detailed studies of the lipopolysaccharides of several species and genera of the Rhodospirillaceae (Weckesser et al., 1979, and more recent paper) have proven to be very useful for the recognition of relationships or dissimilarities between the species of a genus or between different genera. Amino acid sequence

  19. A Combined Molecular and Isotopic Study of Anoxygenic Photosynthesis in Meromictic Lakes of the Northwestern United States

    Science.gov (United States)

    Harris, J. H., IV; Gilhooly, W., III; Crane, E. J., III; Steinman, B.; Shelton, M. R.

    2014-12-01

    Sulfur isotope fractionations within the chemocline can be an indication of green and purple sulfur photosynthetic activity. This isotopic signal is, however, small and variable, on the order of +2-6‰ (Zerkle et al. 2009). It is therefore advantageous to investigate the environmental and ecological effects on this signal so that these influences can be taken into account when estimating the contribution of anoxygenic phototrophs to the sulfur cycle in aquatic environments. This project aims to investigate the ways in which anoxygenic phototroph community structure and lake water geochemistry impact the sulfur isotope fractionation expressed during anoxygenic photosynthesis in meromictic lakes. During the summer of 2013, water column profile analysis of six lakes in the Pacific Northwest (located in eastern Washington and western Montana) were conducted to assess photosynthetically available radiation, salinity, pH, temperature, dissolved solids, and specific conductivity. Water column samples were obtained to determine the sulfur isotopic composition of dissolved sulfate and sulfide, major ion and sulfide concentrations. Microbial samples were also collected for genetic sequencing. Initial results found green (e.g., Chlorobiaceae sp.) and purple (e.g., Lamprocystis purpurea) bacteria at the same depth in one of the study lakes. These data, in addition to the same suite of samples collected in the summer of 2014, provide insight into relationships between the isotopic composition of sulfur (in H2S, S0, and SO4), lake water chemistry, and the presence or absence of green and purple sulfur bacteria.

  20. Anoxygenic Photosynthesis Controls Oxygenic Photosynthesis in a Cyanobacterium from a Sulfidic Spring

    OpenAIRE

    Klatt, Judith M.; Al-Najjar, Mohammad A. A.; Yilmaz, Pelin; Lavik, Gaute; de Beer, Dirk; Polerecky, Lubos

    2015-01-01

    Before the Earth's complete oxygenation (0.58 to 0.55 billion years [Ga] ago), the photic zone of the Proterozoic oceans was probably redox stratified, with a slightly aerobic, nutrient-limited upper layer above a light-limited layer that tended toward euxinia. In such oceans, cyanobacteria capable of both oxygenic and sulfide-driven anoxygenic photosynthesis played a fundamental role in the global carbon, oxygen, and sulfur cycle. We have isolated a cyanobacterium, Pseudanabaena strain FS39,...

  1. A little bit of light goes a long way: the role of phototrophs on mercury cycling.

    Science.gov (United States)

    Grégoire, Daniel S; Poulain, A J

    2014-03-01

    Among toxic metals, mercury (Hg) is a global priority contaminant due to the biomagnification of the most toxic form methylmercury (MeHg) in food webs, even in remote regions, such as the high Arctic. The importance of Hg as a chemical of major concern to human health was underscored by the recent adoption of the Minamata Convention on Mercury, a legally binding treaty that requires government agencies be equipped to monitor processes affecting global mercury transport and cycling. For several decades now, field and laboratory experiments have shown that phototrophs can directly interact with Hg and affect its speciation and fate. While an important body of work on the role of chemotrophic microbes on Hg cycling has been undertaken, the role of phototrophs is too often overlooked. Strikingly, what is known about phototroph-Hg interactions pertains mostly to oxygenic phototrophs with relatively little being known about anoxygenic phototrophs. Ongoing environmental change will no doubt affect the physical and chemical properties of aquatic ecosystems, which in turn will alter all phototrophic community dynamics. How these changes will affect the Hg cycle represent an important knowledge gap. After synthesizing what is currently known about chemotrophic Hg transformations, we describe the current state of knowledge on what is known about how phototrophs (bacteria and algae) affect Hg cycling (i.e., alteration of Hg redox state, Hg scavenging, potential for methylation) as well as describe the cellular and molecular targets of Hg toxicity in phototrophs. We discuss these interactions in an evolutionary context and provide recommendations for future research directions.

  2. Ciliates as engineers of phototrophic biofilms

    NARCIS (Netherlands)

    Weerman, Ellen J.; van der Geest, Harm G.; van der Meulen, Myra D.; Manders, Erik M. M.; van de Koppel, Johan; Herman, Peter M. J.; Admiraal, Wim

    2011-01-01

    1. Phototrophic biofilms consist of a matrix of phototrophs, non-photosynthetic bacteria and extracellular polymeric substances (EPS) which is spatially structured. Despite widespread exploitation of algae and bacteria within phototrophic biofilms, for example by protozoans, the 'engineering' effect

  3. Phototrophic bacteria and their role in the biogeochemical sulfur cycle

    Science.gov (United States)

    Trueper, H. G.

    1985-01-01

    An essential step that cannot be bypassed in the biogeochemical cycle of sulfur today is dissimilatory sulfate reduction by anaerobic bacteria. The enormous amounts of sulfides produced by these are oxidized again either anaerobically by phototrophic bacteria or aerobically by thiobacilli and large chemotrophic bacteria (Beggiatoa, Thiovulum, etc.). Phototrophic bacteria use sulfide, sulfur, thiosulfate, and sulfite as electron donors for photosynthesis. The most obvious intermediate in their oxidative sulfur metabolism is a long chain polysulfide that appears as so called sulfur globules either inside (Chromatiaceae) or outside (Ectothiorhodospiraceae, Chlorobiaceae, and some of the Rhodospirillaceae) the cells. The assimilation of sulfur compounds in phototrophic bacteria is in principle identical with that of nonphototrophic bacteria. However, the Chlorobiaceae and some of the Chromatiaceae and Rhodospirillaceae, unable to reduce sulfate, rely upon reduced sulfur for biosynthetic purposes.

  4. Analysis of cbbL, nifH, and pufLM in Soils from the Sør Rondane Mountains, Antarctica, Reveals a Large Diversity of Autotrophic and Phototrophic Bacteria.

    Science.gov (United States)

    Tahon, Guillaume; Tytgat, Bjorn; Stragier, Pieter; Willems, Anne

    2016-01-01

    Cyanobacteria are generally thought to be responsible for primary production and nitrogen fixation in the microbial communities that dominate Antarctic ecosystems. Recent studies of bacterial communities in terrestrial Antarctica, however, have shown that Cyanobacteria are sometimes only scarcely present, suggesting that other bacteria presumably take over their role as primary producers and diazotrophs. The diversity of key genes in these processes was studied in surface samples from the Sør Rondane Mountains, Dronning Maud Land, using clone libraries of the large subunit of ribulose-1,5-biphosphate carboxylase/oxygenase (RuBisCO) genes (cbbL, cbbM) and dinitrogenase-reductase (nifH) genes. We recovered a large diversity of non-cyanobacterial cbbL type IC in addition to cyanobacterial type IB, suggesting that non-cyanobacterial autotrophs may contribute to primary production. The nifH diversity recovered was predominantly related to Cyanobacteria, particularly members of the Nostocales. We also investigated the occurrence of proteorhodopsin and anoxygenic phototrophy as mechanisms for non-Cyanobacteria to exploit solar energy. While proteorhodopsin genes were not detected, a large diversity of genes coding for the light and medium subunits of the type 2 phototrophic reaction center (pufLM) was observed, suggesting for the first time, that the aerobic photoheterotrophic lifestyle may be important in oligotrophic high-altitude ice-free terrestrial Antarctic habitats.

  5. Ciliates as engineers of phototrophic biofilms.

    NARCIS (Netherlands)

    Weerman, E.J.; Geest, H.G.; Meulen, M.D.; Manders, E.M.M.; Van de Koppel, J.; Herman, P.M.J.; Admiraal, W.

    2011-01-01

    1.Phototrophic biofilms consist of a matrix of phototrophs, non-photosynthetic bacteria and extracellular polymeric substances (EPS) which is spatially structured. Despite widespread exploitation of algae and bacteria within phototrophic biofilms, for example by protozoans, the ‘engineering’ effects

  6. Ciliates as engineers of phototrophic biofilms.

    NARCIS (Netherlands)

    Weerman, E.J.; van der Geest, H.G.; van der Meulen, M.D; Manders, E.M.M.; van de Koppel, J.; Herman, P.M.J.; Admiraal, W.

    2011-01-01

    1. Phototrophic biofilms consist of a matrix of phototrophs, non-photosynthetic bacteria and extracellular polymeric substances (EPS) which is spatially structured. Despite widespread exploitation of algae and bacteria within phototrophic biofilms, for example by protozoans, the ‘engineering’ effect

  7. Phototrophic pigment production with microalgae

    NARCIS (Netherlands)

    Mulders, K.J.M.

    2014-01-01

    Abstract

    Microalgal pigments are regarded as natural alternatives for food colorants. To facilitate optimization of microalgae-based pigment production, this thesis aimed to obtain key insights in the pigment metabolism of phototrophic microalgae, with the main  focus

  8. Microbial ecology of phototrophic biofilms

    NARCIS (Netherlands)

    Roeselers, G.

    2007-01-01

    Biofilms are layered structures of microbial cells and an extracellular matrix of polymeric substances, associated with surfaces and interfaces. Biofilms trap nutrients for growth of the enclosed microbial community and help prevent detachment of cells from surfaces in flowing systems. Phototrophic

  9. Biogeography of thermophilic phototrophic bacteria belonging to Roseiflexus genus.

    Science.gov (United States)

    Gaisin, Vasil A; Grouzdev, Denis S; Namsaraev, Zorigto B; Sukhacheva, Marina V; Gorlenko, Vladimir M; Kuznetsov, Boris B

    2016-03-01

    Isolated environments such as hot springs are particularly interesting for studying the microbial biogeography. These environments create an 'island effect' leading to genetic divergence. We studied the phylogeographic pattern of thermophilic anoxygenic phototrophic bacteria, belonging to the Roseiflexus genus. The main characteristic of the observed pattern was geographic and geochronologic fidelity to the hot springs within Circum-Pacific and Alpine-Himalayan-Indonesian orogenic belts. Mantel test revealed a correlation between genetic divergence and geographic distance among the phylotypes. Cluster analysis revealed a regional differentiation of the global phylogenetic pattern. The phylogeographic pattern is in correlation with geochronologic events during the break up of Pangaea that led to the modern configuration of continents. To our knowledge this is the first geochronological scenario of intercontinental prokaryotic taxon divergence. The existence of the modern phylogeographic pattern contradicts with the existence of the ancient evolutionary history of the Roseiflexus group proposed on the basis of its deep-branching phylogenetic position. These facts indicate that evolutionary rates in Roseiflexus varied over a wide range.

  10. Arsenic(III) fuels anoxygenic photosynthesis in hot spring biofilms from Mono Lake, California

    Science.gov (United States)

    Kulp, T.R.; Hoeft, S.E.; Asao, M.; Madigan, M.T.; Hollibaugh, J.T.; Fisher, J.C.; Stolz, J.F.; Culbertson, C.W.; Miller, L.G.; Oremland, R.S.

    2008-01-01

    Phylogenetic analysis indicates that microbial arsenic metabolism is ancient and probably extends back to the primordial Earth. In microbial biofilms growing on the rock surfaces of anoxic brine pools fed by hot springs containing arsenite and sulfide at high concentrations, we discovered light-dependent oxidation of arsenite [As(III)] to arsenate [As(V)] occurring under anoxic conditions. The communities were composed primarily of Ectothiorhodospira-like purple bacteria or Oscillatoria-like cyanobacteria. A pure culture of a photosynthetic bacterium grew as a photoautotroph when As(III) was used as the sole photosynthetic electron donor. The strain contained genes encoding a putative As(V) reductase but no detectable homologs of the As(III) oxidase genes of aerobic chemolithotrophs, suggesting a reverse functionality for the reductase. Production of As(V) by anoxygenic photosynthesis probably opened niches for primordial Earth's first As(V)-respiring prokaryotes.

  11. Engineering and Coordination of Regulatory Networks and Intracellular Complexes to Maximize Hydrogen Production by Phototrophic Microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    James C. Liao

    2012-05-22

    This project is a collaboration with F. R. Tabita of Ohio State. Our major goal is to understand the factors and regulatory mechanisms that influence hydrogen production. The organisms to be utilized in this study, phototrophic microorganisms, in particular nonsulfur purple (NSP) bacteria, catalyze many significant processes including the assimilation of carbon dioxide into organic carbon, nitrogen fixation, sulfur oxidation, aromatic acid degradation, and hydrogen oxidation/evolution. Our part of the project was to develop a modeling technique to investigate the metabolic network in connection to hydrogen production and regulation. Organisms must balance the pathways that generate and consume reducing power in order to maintain redox homeostasis to achieve growth. Maintaining this homeostasis in the nonsulfur purple photosynthetic bacteria is a complex feat with many avenues that can lead to balance, as these organisms possess versatile metabolic capabilities including anoxygenic photosynthesis, aerobic or anaerobic respiration, and fermentation. Growth is achieved by using H{sub 2} as an electron donor and CO{sub 2} as a carbon source during photoautotrophic and chemoautotrophic growth, where CO{sub 2} is fixed via the Calvin-Benson-Bassham (CBB) cycle. Photoheterotrophic growth can also occur when alternative organic carbon compounds are utilized as both the carbon source and electron donor. Regardless of the growth mode, excess reducing equivalents generated as a result of oxidative processes, must be transferred to terminal electron acceptors, thus insuring that redox homeostasis is maintained in the cell. Possible terminal acceptors include O{sub 2}, CO{sub 2}, organic carbon, or various oxyanions. Cells possess regulatory mechanisms to balance the activity of the pathways which supply energy, such as photosynthesis, and those that consume energy, such as CO{sub 2} assimilation or N{sub 2} fixation. The major route for CO{sub 2} assimilation is the CBB

  12. Divergent mitochondrial respiratory chains in phototrophic relatives of apicomplexan parasites

    KAUST Repository

    Flegontov, Pavel

    2015-02-06

    Four respiratory complexes and ATP-synthase represent central functional units in mitochondria. In some mitochondria and derived anaerobic organelles, a few or all of these respiratory complexes have been lost during evolution. We show that the respiratory chain of Chromera velia, a phototrophic relative of parasitic apicomplexans, lacks complexes I and III, making it a uniquely reduced aerobic mitochondrion. In Chromera, putative lactate:cytochrome c oxidoreductases are predicted to transfer electrons from lactate to cytochrome c, rendering complex III unnecessary. The mitochondrial genome of Chromera has the smallest known protein-coding capacity of all mitochondria, encoding just cox1 and cox3 on heterogeneous linear molecules. In contrast, another photosynthetic relative of apicomplexans, Vitrella brassicaformis, retains the same set of genes as apicomplexans and dinoflagellates (cox1, cox3, and cob). © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  13. Anoxygenic photosynthesis modulated Proterozoic oxygen and sustained Earth's middle age

    OpenAIRE

    2009-01-01

    Molecular oxygen (O2) began to accumulate in the atmosphere and surface ocean ca. 2,400 million years ago (Ma), but the persistent oxygenation of water masses throughout the oceans developed much later, perhaps beginning as recently as 580–550 Ma. For much of the intervening interval, moderately oxic surface waters lay above an oxygen minimum zone (OMZ) that tended toward euxinia (anoxic and sulfidic). Here we illustrate how contributions to primary production by anoxygenic photoautotrophs (i...

  14. Deep-water anoxygenic photosythesis in a ferruginous chemocline

    DEFF Research Database (Denmark)

    Crowe, Sean; Maresca, J. A.; Jones, CarriAyne

    2014-01-01

    Ferruginous Lake Matano, Indonesia hosts one of the deepest anoxygenic photosynthetic communities on Earth. This community is dominated by low-light adapted, BChl e-synthesizing green sulfur bacteria (GSB), which comprise ~25% of the microbial community immediately below the oxic-anoxic boundary...... (OAB; 115-120 m in 2010). The size of this community is dependent on the mixing regime within the lake and the depth of the OAB-at ~117 m, the GSB live near their low-light limit. Slow growth and C-fixation rates suggest that the Lake Matano GSB can be supported by sulfide even though it only...

  15. Microscale sulfur cycling in the phototrophic pink berry consortia of the Sippewissett Salt Marsh.

    Science.gov (United States)

    Wilbanks, Elizabeth G; Jaekel, Ulrike; Salman, Verena; Humphrey, Parris T; Eisen, Jonathan A; Facciotti, Marc T; Buckley, Daniel H; Zinder, Stephen H; Druschel, Gregory K; Fike, David A; Orphan, Victoria J

    2014-11-01

    Microbial metabolism is the engine that drives global biogeochemical cycles, yet many key transformations are carried out by microbial consortia over short spatiotemporal scales that elude detection by traditional analytical approaches. We investigate syntrophic sulfur cycling in the 'pink berry' consortia of the Sippewissett Salt Marsh through an integrative study at the microbial scale. The pink berries are macroscopic, photosynthetic microbial aggregates composed primarily of two closely associated species: sulfide-oxidizing purple sulfur bacteria (PB-PSB1) and sulfate-reducing bacteria (PB-SRB1). Using metagenomic sequencing and (34) S-enriched sulfate stable isotope probing coupled with nanoSIMS, we demonstrate interspecies transfer of reduced sulfur metabolites from PB-SRB1 to PB-PSB1. The pink berries catalyse net sulfide oxidation and maintain internal sulfide concentrations of 0-500 μm. Sulfide within the berries, captured on silver wires and analysed using secondary ion mass spectrometer, increased in abundance towards the berry interior, while δ(34) S-sulfide decreased from 6‰ to -31‰ from the exterior to interior of the berry. These values correspond to sulfate-sulfide isotopic fractionations (15-53‰) consistent with either sulfate reduction or a mixture of reductive and oxidative metabolisms. Together this combined metagenomic and high-resolution isotopic analysis demonstrates active sulfur cycling at the microscale within well-structured macroscopic consortia consisting of sulfide-oxidizing anoxygenic phototrophs and sulfate-reducing bacteria.

  16. Anoxygenic photosynthesis modulated Proterozoic oxygen and sustained Earth's middle age.

    Science.gov (United States)

    Johnston, D T; Wolfe-Simon, F; Pearson, A; Knoll, A H

    2009-10-06

    Molecular oxygen (O(2)) began to accumulate in the atmosphere and surface ocean ca. 2,400 million years ago (Ma), but the persistent oxygenation of water masses throughout the oceans developed much later, perhaps beginning as recently as 580-550 Ma. For much of the intervening interval, moderately oxic surface waters lay above an oxygen minimum zone (OMZ) that tended toward euxinia (anoxic and sulfidic). Here we illustrate how contributions to primary production by anoxygenic photoautotrophs (including physiologically versatile cyanobacteria) influenced biogeochemical cycling during Earth's middle age, helping to perpetuate our planet's intermediate redox state by tempering O(2) production. Specifically, the ability to generate organic matter (OM) using sulfide as an electron donor enabled a positive biogeochemical feedback that sustained euxinia in the OMZ. On a geologic time scale, pyrite precipitation and burial governed a second feedback that moderated sulfide availability and water column oxygenation. Thus, we argue that the proportional contribution of anoxygenic photosynthesis to overall primary production would have influenced oceanic redox and the Proterozoic O(2) budget. Later Neoproterozoic collapse of widespread euxinia and a concomitant return to ferruginous (anoxic and Fe(2+) rich) subsurface waters set in motion Earth's transition from its prokaryote-dominated middle age, removing a physiological barrier to eukaryotic diversification (sulfide) and establishing, for the first time in Earth's history, complete dominance of oxygenic photosynthesis in the oceans. This paved the way for the further oxygenation of the oceans and atmosphere and, ultimately, the evolution of complex multicellular organisms.

  17. Anoxygenic growth of cyanobacteria on Fe(II) and their associated biosignatures: Implications for biotic contributions to Precambrian Banded Iron Formations

    Science.gov (United States)

    Parenteau, M.; Jahnke, L. L.; Cady, S. L.; Pierson, B.

    2011-12-01

    Banded Iron Formations (BIFs) are widespread Precambrian sedimentary deposits that accumulated in deep ocean basins or shallow platformal areas with inputs of reduced iron (Fe(II)) and silica from deep ocean hydrothermal activity. There is debate as to whether abiotic or biotic mechanisms were responsible for the oxidation of aqueous Fe(II) and the subsequent accumulation of ferric iron (Fe(III)) mineral assemblages in BIFs. Biotic Fe(II) oxidation could have occurred indirectly as a result of the photosynthetic production of oxygen by cyanobacteria, or could have been directly mediated by anoxygenic phototrophs or chemolithotrophs. The anoxygenic use of Fe(II) as an electron donor for photosynthesis has also been hypothesized in cyanobacteria, representing another biotic mechanism by which Fe(II) could be oxidized in BIFs. This type of photoferrotrophic metabolism may also represent a key step in the evolution of oxygenic photosynthesis. Members of our group have speculated that an intermediate reductant such as Fe(II) could have acted as a transitional electron donor before water. The widespread abundance of Fe(II) in Archean and Neoproterozoic ferruginous oceans would have made it particularly suitable as an electron donor for photosynthesis. We have been searching for modern descendants of such an ancestral "missing link" cyanobacterium in the phototrophic mats at Chocolate Pots, a hot spring in Yellowstone National Park with a constant outflow of anoxic Fe(II)-rich thermal water. Our physiological ecology study of the Synechococcus-Chloroflexi mat using C-14 bicarbonate uptake and autoradiography experiments revealed that the cyanobacteria grow anoxygenically using Fe(II) as an electron donor for photosynthesis in situ. An initial set of similar experiments substituting C-13 bicarbonate as the tracer was used to characterize labeling of the community lipid biomarker signature and confirm the C-14 results. Under light conditions with and without Fe(II), the C

  18. Anthocyanin-dependent anoxygenic photosynthesis in coloured flower petals?

    Science.gov (United States)

    Lysenko, Vladimir; Varduny, Tatyana

    2013-11-01

    Chlorophylless flower petals are known to be composed of non-photosynthetic tissues. Here, we show that the light energy storage that can be photoacoustically measured in flower petals of Petunia hybrida is approximately 10-12%. We found that the supposed chlorophylless photosynthesis is an anoxygenic, anthocyanin-dependent process occurring in blue flower petals (ADAPFP), accompanied by non-respiratory light-dependent oxygen uptake and a 1.5-fold photoinduced increase in ATP levels. Using a simple, adhesive tape stripping technique, we have obtained a backside image of an intact flower petal epidermis, revealing sword-shaped ingrowths connecting the cell wall and vacuole, which is of interest for the further study of possible vacuole-related photosynthesis. Approaches to the interpretations of ADAPFP are discussed, and we conclude that these results are not impossible in terms of the known photochemistry of anthocyanins.

  19. Spectral light measurements in microbenthic phototrophic communities with a fiber-optic microprobe coupled to a sensitive diode array detector

    Energy Technology Data Exchange (ETDEWEB)

    Kuehl, M. (Univ. of Aarhus (Denmark)); Joergensen, B.B. (Max-Planck-Inst. for Marine Microbiology, Bremen (Germany))

    1992-12-01

    A diode array detector system for microscale light measurements with fiber-optic microprobes was developed; it measures intensities of 400-900-nm light over >6 orders of magnitude with a spectral resolution of 2-5 nm. Fiber-optic microprobes to measure field radiance or scalar irradiance were coupled to the detector system and used for spectral light measurements in hypersaline microbial mats and in laminated phototrophic communities of coastal sediments. The vertical distribution of major photopigments of microalgae, cyanobacteria, and anoxygenic phototrophic bacteria could be identified from extinction maxima in measured radiance spectra at 430-550 nm (Chl a and carotenoids), 620-625 nm (phycocyanin), 675 nm (Chl a), 745-750 nm (BChl c), 800-810 nm, and 860-880 nm (BChl a). Scalar irradiance spectra exhibited a different spectral composition and a higher light intensity at the sediment surface as compared to incident light. IR light thus reached 200% of incident at the sediment surface. Maximal light penetration was found for IR light, whereas visible light was strongly attenuated in the upper 0-2 mm of the sediment. Measurements of photon scalar irradiance (400-700 nm) were combined with microelectrode measurements of oxygenic photosynthesis in the coastal sediment. With an incident light intensity of 200 [mu]Einst m[sup [minus]2]s[sup [minus]1], photon scalar irradiance reached a maximum of 283 [mu]Einst m[sup [minus]2]s[sup [minus]1] at the sediment surface. The lower boundary of the euphotic zone was 2.2 mm below the surface at a light intensity of 12 [mu]Einst m[sup [minus]2]s[sup [minus]1]. 20 refs., 6 figs.

  20. The genetic basis of anoxygenic photosynthetic arsenite oxidation

    Science.gov (United States)

    Hernandez-Maldonado, Jamie; Sanchez-Sedillo, Benjamin; Stoneburner, Brendon; Boren, Alison; Miller, Laurence G.; McCann, Shelley; Rosen, Michael R.; Oremland, Ronald S.; Saltikov, Chad W.

    2017-01-01

    “Photoarsenotrophy”, the use of arsenite as an electron donor for anoxygenic photosynthesis, is thought to be an ancient form of phototrophy along with the photosynthetic oxidation of Fe(II), H2S, H2, and NO2-. Photoarsenotrophy was recently identified from Paoha Island's (Mono Lake, CA) arsenic-rich hot springs. The genomes of several photoarsenotrophs revealed a gene cluster, arxB2AB1CD, where arxA is predicted to encode for the sole arsenite oxidase. The role of arxA in photosynthetic arsenite oxidation was confirmed by disrupting the gene in a representative photoarsenotrophic bacterium, resulting in the loss of light-dependent arsenite oxidation. In situ evidence of active photoarsenotrophic microbes was supported by arxA mRNA detection for the first time, in red-pigmented microbial mats within the hot springs of Paoha Island. This work expands on the genetics for photosynthesis coupled to new electron donors and elaborates on known mechanisms for arsenic metabolism, thereby highlighting the complexities of arsenic biogeochemical cycling.

  1. Microenvironmental Ecology of Phototrophs from Extreme Environments

    DEFF Research Database (Denmark)

    Trampe, Erik

    and finalized in part of my master thesis and presents a new multicolor (red, green, and blue excitation light) system for microscopic imaging of variable chlorophyll fluorescence. In addition to a thorough description of the commercially available imaging system, we developed an additional custom build......In the three manuscripts presented in part one of this thesis, I analyse the physicochemical parameters, microenvironmental ecology and species composition of microbial phototrophs in ikaite tufa columns. This work was not easy, and encompassed underwater sampling and microsensor work demanding...... of which have now been tentatively identified taxonomically, and their phylogenetic relationships been evaluated (Manuscript 3). Part 2 of the thesis includes three manuscripts that focus on cyanobacteria that have evolved special photopigments in contrast to other cyanobacteria. In Manuscript 4 we show...

  2. Deep-water anoxygenic photosythesis in a ferruginous chemocline.

    Science.gov (United States)

    Crowe, S A; Maresca, J A; Jones, C; Sturm, A; Henny, C; Fowle, D A; Cox, R P; Delong, E F; Canfield, D E

    2014-07-01

    Ferruginous Lake Matano, Indonesia hosts one of the deepest anoxygenic photosynthetic communities on Earth. This community is dominated by low-light adapted, BChl e-synthesizing green sulfur bacteria (GSB), which comprise ~25% of the microbial community immediately below the oxic-anoxic boundary (OAB; 115-120 m in 2010). The size of this community is dependent on the mixing regime within the lake and the depth of the OAB-at ~117 m, the GSB live near their low-light limit. Slow growth and C-fixation rates suggest that the Lake Matano GSB can be supported by sulfide even though it only accumulates to scarcely detectable (low μm to nm) concentrations. A model laboratory strain (Chlorobaculum tepidum) is indeed able to access HS- for oxidation at nm concentrations. Furthermore, the GSB in Lake Matano possess a full complement of S-oxidizing genes. Together, this physiological and genetic information suggests that deep-water GSB can be supported by a S-cycle, even under ferruginous conditions. The constraints we place on the metabolic capacity and physiology of GSB have important geobiological implications. Biomarkers diagnostic of GSB would be a good proxy for anoxic conditions but could not discriminate between euxinic and ferruginous states, and though GSB biomarkers could indicate a substantial GSB community, such a community may exist with very little metabolic activity. The light requirements of GSB indicate that at light levels comparable to those in the OAB of Lake Matano or the Black Sea, GSB would have contributed little to global ocean primary production, nutrient cycling, and banded iron formation (BIF) deposition in the Precambrian. Before the proliferation of oxygenic photosynthesis, shallower OABs and lower light absorption in the ocean's surface waters would have permitted greater light availability to GSB, potentially leading to a greater role for GSB in global biogeochemical cycles.

  3. Buoyant densities of phototrophic sulfur bacteria and cyanobacteria

    Science.gov (United States)

    Guerrero, R.

    1985-01-01

    The buoyant densities of bacterial cells are greatly influenced by the accumulation of intracellular reserve material. The buoyant density of phototrophic bacteria that are planktonic is of particular interest, since these organisms must remain in the photic zone of the water column for optimal growth. Separation of cells by their buoyant density may also be of use in separating and identifying organisms from a natural population. The bacteria used were obtained from pure cultures, enrichments, or samples taken directly from the environment.

  4. Rhodovastum atsumiense gen. nov., sp. nov., a phototrophic alphaproteobacterium isolated from paddy soil.

    Science.gov (United States)

    Okamura, Keiko; Hisada, Takayoshi; Kanbe, Toshio; Hiraishi, Akira

    2009-02-01

    A photoorganotrophic alphaproteobacterium designated strain G2-11(T) was isolated from submerged paddy soil. This bacterium had relatively large, oval to rod-shaped cells (2.0-3.0x3.0-10 microm). Cells were motile by means of single polar flagella. The color of phototrophically growing cultures was reddish-brown. The cell extract had absorption maxima at 375, 465, 492, 529, 592, 804, and 844 nm, indicating the presence of bacteriochlorophyll a and carotenoides of the spirilloxanthin series. Vesicular intracytoplasmic membranes were present. The main component of cellular fatty acids was C(18:1)omega7c. Ubiquinone-10 and rhodoquinone-10 were the major quinones. A 16S rRNA gene sequence analysis revealed that the isolate is closest to the acidophilic aerobic photosynthetic bacterium Acidisphaera rubrifaciens strain HS-AP3(T) (93.3% similarity). The G+C content of genomic DNA is 67.8 mol%. The name Rhodovastum atsumiense gen. nov., sp. nov. is proposed for the novel isolate. The type strain is strain G2-11(T) (=NBRC 104268(T)=KCTC 5708(T)).

  5. What Is Aerobic Dancing?

    Science.gov (United States)

    ... than 24 million people participate in aerobics. Aerobic dance has blossomed into a sport for all to have fun while losing weight and keeping in shape. There are varied forms of aerobics including low-impact, swim and other water aerobics is popular. Dance is still the predominant form and may be ...

  6. Retrograde bilin signaling enables Chlamydomonas greening and phototrophic survival

    Science.gov (United States)

    Duanmu, Deqiang; Casero, David; Dent, Rachel M.; Gallaher, Sean; Yang, Wenqiang; Rockwell, Nathan C.; Martin, Shelley S.; Pellegrini, Matteo; Niyogi, Krishna K.; Merchant, Sabeeha S.; Grossman, Arthur R.; Lagarias, J. Clark

    2013-01-01

    The maintenance of functional chloroplasts in photosynthetic eukaryotes requires real-time coordination of the nuclear and plastid genomes. Tetrapyrroles play a significant role in plastid-to-nucleus retrograde signaling in plants to ensure that nuclear gene expression is attuned to the needs of the chloroplast. Well-known sites of synthesis of chlorophyll for photosynthesis, plant chloroplasts also export heme and heme-derived linear tetrapyrroles (bilins), two critical metabolites respectively required for essential cellular activities and for light sensing by phytochromes. Here we establish that Chlamydomonas reinhardtii, one of many chlorophyte species that lack phytochromes, can synthesize bilins in both plastid and cytosol compartments. Genetic analyses show that both pathways contribute to iron acquisition from extracellular heme, whereas the plastid-localized pathway is essential for light-dependent greening and phototrophic growth. Our discovery of a bilin-dependent nuclear gene network implicates a widespread use of bilins as retrograde signals in oxygenic photosynthetic species. Our studies also suggest that bilins trigger critical metabolic pathways to detoxify molecular oxygen produced by photosynthesis, thereby permitting survival and phototrophic growth during the light period. PMID:23345435

  7. Cyanobacteria in sulfidic spring microbial mats can perform oxygenic and anoxygenic photosynthesis simultaneously during an entire diurnal period

    Directory of Open Access Journals (Sweden)

    Judith M Klatt

    2016-12-01

    Full Text Available We used microsensors to study the regulation of oxygenic and anoxygenic photosynthesis by light and sulfide in a cyanobacterium dominating microbial mats from cold sulfidic springs. Both photosynthetic modes were performed simultaneously over all H2S concentrations (1–2200 µM and irradiances (4–52 µmol photons m-2 s-1 tested. Anoxygenic photosynthesis increased with H2S concentration while the sum of oxygenic and anoxygenic photosynthetic rates was constant at each light intensity. Thus, the total photosynthetically driven electron transport rate was solely controlled by the irradiance level. The partitioning between the rates of these two photosynthetic modes was regulated by both light and H2S concentration. The plastoquinone pool (PQ receives electrons from sulfide:quinone:reductase (SQR in anoxygenic photosynthesis and from photosystem II (PSII in oxygenic photosynthesis. It is thus the link in the electron transport chain where both pathways intersect, and the compound that controls their partitioning. We fitted our data with a model of the photosynthetic electron transport that includes the kinetics of plastoquinone reduction and oxidation. The model results confirmed that the observed partitioning between photosynthetic modes can be explained by a simple kinetic control based on the affinity of SQR and PSII towards PQ. The SQR enzyme and PSII have similar affinities towards PQ, which explains the concurrent oxygenic and anoxygenic photosynthesis over an astonishingly wide range of H2S concentrations and irradiances. The elegant kinetic control of activity makes the cyanobacterium successful in the fluctuating spring environment. We discuss how these specific regulation mechanisms may have played a role in ancient H2S-rich oceans.

  8. Isolation of a significant fraction of non-phototroph diversity from a desert Biological Soil Crust

    Directory of Open Access Journals (Sweden)

    Ulisses eNunes da Rocha

    2015-04-01

    Full Text Available Biological Soil Crusts (BSCs are organosedimentary assemblages comprised of microbes and minerals in topsoil of terrestrial environments. BSCs strongly impact soil quality in dryland ecosystems (e.g., soil structure and nutrient yields due to pioneer species such as Microcoleus vaginatus; phototrophs that produce filaments that bind the soil together, and support an array of heterotrophic microorganisms. These microorganisms in turn contribute to soil stability and biogeochemistry of BSCs. Non-cyanobacterial populations of BSCs are less well known than cyanobacterial populations. Therefore, we attempted to isolate a broad range of numerically significant and phylogenetically representative BSC aerobic heterotrophs. Combining simple pre-treatments (hydration of BSCs under dark and light and isolation strategies (media with varying nutrient availability and protection from oxidative stress we recovered 402 bacterial and one fungal isolate in axenic culture, which comprised 116 phylotypes (at 97% 16S rRNA gene sequence homology, 115 bacterial and one fungal. Each medium enriched a mostly distinct subset of phylotypes, and cultivated phylotypes varied due to the BSC pre-treatment. The fraction of the total phylotype diversity isolated, weighted by relative abundance in the community, was determined by the overlap between isolate sequences and OTUs reconstructed from metagenome or metatranscriptome reads. Together, more than 8% of relative abundance of OTUs in the metagenome was represented by our isolates, a cultivation efficiency much larger than typically expected from most soils. We conclude that simple cultivation procedures combined with specific pre-treatment of samples afford a significant reduction in the culturability gap, enabling physiological and metabolic assays that rely on ecologically relevant axenic cultures.

  9. Phototrophic microorganisms in biofilm samples from Vernjika Cave, Serbia

    Science.gov (United States)

    Popović, Slađana; Jovanović, Jelena; Predojević, Dragana; Trbojević, Ivana; Blagojević, Ana; Subakov Simić, Gordana

    2016-04-01

    Caves represent specific natural monuments in terms of structure, complexity and beauty which can be found worldwide. Even though they are considered extreme environments, they are still a unique habitat for a large number of organisms that grow and proliferate here. Often can be seen that the cave walls are differently coloured as a consequence of the biofilm development. Biofilms represent complex communities of microorganisms that can develop on different kind of surfaces, including various rock surfaces. Each microbe species play a different role in a community, but their development on stone surfaces can cause substantial damage to the substrates through different mechanisms of biodeterioration and degradation. There is an increased interest in the phototrophic component of biofilms (aerophytic cyanobacteria and algae), especially cyanobacteria, an ancient microorganisms capable to survive the most diverse extreme conditions. These phototrophs can easily be found at cave entrances illuminated by direct or indirect sunlight and areas near artificial lights. Cyanobacteria and algae were investigated in biofilm samples taken from the entrance of Vernjika Cave in Eastern Serbia. Cyanobacteria, Chlorophyta and Bacillariophyta were documented, with Cyanobacteria as a group with the highest number of recorded taxa. Chroococcalean species were the most diverse with the most frequently encountered species from the genus Gloeocapsa. Phormidium and Nostoc species were commonly recorded Oscillatoriales and Nostocles, respectively. Among Oscillatoriales species, it was noticed that one Phormidium species precipitates CaCO3 on it's sheats. Trebouxia sp. and Desmococcus olivaceus were frequently documented Chlorophyta, and representatives of Bacillariophyta were exclusively aerophytic taxa, mostly belonging to the genera Luticola and Humidophila. Measured ecological parameters, temperature and relative humidity, were influenced by the external climatic changes, while light

  10. Metagenomic evidence for the presence of phototrophic Gemmatimonadetes bacteria in diverse environments

    DEFF Research Database (Denmark)

    Zeng, Yonghui; Baumbach, Jan; Barbosa, Eudes Guilherme Vieira

    2016-01-01

    , biofilms, plant surfaces, intertidal sediment, soils, springs, and wastewater treatment plants, but none from marine waters or sediment. Phototrophic Gemmatimonadetes bacteria make up 0.4∼11.9% of whole phototrophic microbial communities in these habitats. Unexpectedly, an almost complete 37.9 kb long...... photosynthesis gene cluster (PGC) with identical gene composition and arrangement to those in G. phototrophica was reconstructed from the Odense wastewater metagenome, only differing in a 7.2 kb long non-photosynthesis-gene insert. These data suggest that phototrophic Gemmatimonadetes bacteria are much more...

  11. Mushroom speleothems: Stromatolites that formed in the absence of phototrophs

    Directory of Open Access Journals (Sweden)

    Tomaso eBontognali

    2016-04-01

    Full Text Available Unusual speleothems resembling giant mushrooms occur in Santa Catalina Cave, Cuba. Although these mineral buildups are considered a natural heritage, their composition and formation mechanism remain poorly understood. Here we characterize their morphology and mineralogy and present a model for their genesis. We propose that the mushrooms, which are mainly comprised of calcite and aragonite, formed during four different phases within an evolving cave environment. The stipe of the mushroom is an assemblage of three well-known speleothems: a stalagmite surrounded by calcite rafts that were subsequently encrusted by cave clouds (mammilaries. More peculiar is the cap of the mushroom, which is morphologically similar to cerebroid stromatolites and thrombolites of microbial origin occurring in marine environments. Scanning electron microscopy investigations of this last unit revealed the presence of fossilized extracellular polymeric substances (EPS – the constituents of biofilms and microbial mats. These organic microstructures are mineralized with Ca-carbonate, suggesting that the mushroom cap formed through a microbially-influenced mineralization process. The existence of cerebroid Ca-carbonate buildups forming in dark caves (i.e., in the absence of phototrophs has interesting implications for the study of fossil microbialites preserved in ancient rocks, which are today considered as one of the earliest evidence for life on Earth.

  12. Cultivation of Isochrysis galbana in phototrophic, heterotrophic, and mixotrophic conditions.

    Science.gov (United States)

    Alkhamis, Yousef; Qin, Jian G

    2013-01-01

    This study compared the growth and biomass production of Isochrysis galbana under hetero-, mixo-, and phototrophic conditions using different organic carbon sources. The growth of I. galbana was inhibited in heterotrophy but was enhanced in mixotrophy compared to that in phototrophy. Subsequently, the influences of organic carbon and environmental factors (light and salinity) on the growth of I. galbana were further investigated. Algal dry weight increased as glycerol concentrations increased from 0 to 200 mmol and the highest algal production occurred at 50 mmol glycerol. At a range of light intensities of 25-200 μ mol photons m(-2) s(-2), the highest algal growth rate occurred at 100 photons μ mol m(-2) s(-2). The growth of I. galbana was significantly affected by photoperiod, and the maximal dry weight was obtained at 12 h light and 12 h dark. In the salinity test, I. galbana could grow in a wide range of salinities from 10 to 65 ‰, but the 35 ‰ salinity was optimal. This study suggests that the growth and production of I. galbana can be improved using mixotrophic culture at 50 mmol glycerol in 35 ‰ salinity.

  13. Mushroom speleothems: Stromatolites that formed in the absence of phototrophs

    Science.gov (United States)

    Bontognali, Tomaso; D'Angeli, Ilenia; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano; Gonzales, Esteban; DeWaele, Jo

    2016-04-01

    Unusual speleothems resembling giant mushrooms occur in Santa Catalina Cave, Cuba. Although these mineral buildups are considered a natural heritage, their composition and formation mechanism remain poorly understood. Here we characterize their morphology and mineralogy and present a model for their genesis. We propose that the mushrooms, which are mainly comprised of calcite and aragonite, formed during four different phases within an evolving cave environment. The stipe of the mushroom is an assemblage of three well-known speleothems: a stalagmite surrounded by calcite rafts that were subsequently encrusted by cave clouds (mammilaries). More peculiar is the cap of the mushroom, which is morphologically similar to cerebroid stromatolites and thrombolites of microbial origin occurring in marine environments. Scanning electron microscopy investigations of this last unit revealed the presence of fossilized extracellular polymeric substances (EPS) - the constituents of biofilms and microbial mats. These organic microstructures are mineralized with Ca-carbonate, suggesting that the mushroom cap formed through a microbially-influenced mineralization process. The existence of cerebroid Ca-carbonate buildups forming in dark caves (i.e., in the absence of phototrophs) has interesting implications for the study of fossil microbialites preserved in ancient rocks, which are today considered as one of the earliest evidence for life on Earth.

  14. Analysis of lipophilic pigments from a phototrophic microbial mat community by high performance liquid chromatography

    Science.gov (United States)

    Palmisano, A. C.; Cronin, S. E.; Des Marais, D. J.

    1988-01-01

    As assay for lipophilic pigments in phototrophic microbial mat communities using reverse phase-high performance liquid chromatography was developed which allows the separation of 15 carotenoids and chloropigments in a single 30 min program. Lipophilic pigments in a laminated mat from a commercial salina near Laguna Guerrero Negro, Baja California Sur, Mexico reflected their source organisms. Myxoxanthophyll, echinenone, canthaxanthin, and zeaxanthin were derived from cyanobacteria; chlorophyll c, and fucoxanthin from diatoms; chlorophyll a from cyanobacteria and diatoms; bacteriochlorophylls a and c, bacteriophaeophytin a, and gamma-carotene from Chloroflexus spp.; and beta-carotene from a variety of phototrophs. Sensitivity of detection was 0.6-6.1 ng for carotenoids and 1.7-12 ng for most chloropigments. This assay represents a significant improvement over previous analyses of lipophilic pigments in microbial mats and promises to have a wider application to other types of phototrophic communities.

  15. Genes, Genomes, and Assemblages of Modern Anoxygenic Photosynthetic Cyanobacteria as Proxies for Ancient Cyanobacteria

    Science.gov (United States)

    Grim, S. L.; Dick, G.

    2015-12-01

    Oxygenic photosynthetic (OP) cyanobacteria were responsible for the production of O2 during the Proterozoic. However, the extent and degree of oxygenation of the atmosphere and oceans varied for over 2 Ga after OP cyanobacteria first appeared in the geologic record. Cyanobacteria capable of anoxygenic photosynthesis (AP) may have altered the trajectory of oxygenation, yet the scope of their role in the Proterozoic is not well known. Modern cyanobacterial populations from Middle Island Sinkhole (MIS), Michigan and a handful of cultured cyanobacterial strains, are capable of OP and AP. With their metabolic versatility, these microbes may approximate ancient cyanobacterial assemblages that mediated Earth's oxygenation. To better characterize the taxonomic and genetic signatures of these modern AP/OP cyanobacteria, we sequenced 16S rRNA genes and conducted 'omics analyses on cultured strains, lab mesocosms, and MIS cyanobacterial mat samples collected over multiple years from May to September. Diversity in the MIS cyanobacterial mat is low, with one member of Oscillatoriales dominating at all times. However, Planktothrix members are more abundant in the cyanobacterial community in late summer and fall. The shift in cyanobacterial community composition may be linked to seasonally changing light intensity. In lab mesocosms of MIS microbial mat, we observed a shift in dominant cyanobacterial groups as well as the emergence of Chlorobium, bacteria that specialize in AP. These shifts in microbial community composition and metabolism are likely in response to changing environmental parameters such as the availability of light and sulfide. Further research is needed to understand the impacts of the changing photosynthetic community on oxygen production and the entire microbial consortium. Our study connects genes and genomes of AP cyanobacteria to their environment, and improves understanding of cyanobacterial metabolic strategies that may have shaped Earth's redox evolution.

  16. Anoxygenic photosynthesis controls oxygenic photosynthesis in a cyanobacterium from a sulfidic spring

    NARCIS (Netherlands)

    Klatt, Judith M.; Al-Najjar, Mohammad A A; Yilmaz, Pelin; Lavik, Gaute; de Beer, Dirk; Polerecky, Lubos

    2015-01-01

    Before the Earth's complete oxygenation (0.58 to 0.55 billion years [Ga] ago), the photic zone of the Proterozoic oceans was probably redox stratified, with a slightly aerobic, nutrient-limited upper layer above a light-limited layer that tended toward euxinia. In such oceans, cyanobacteria capable

  17. Physiological response of BSC phototrophic community to EPS removal

    Science.gov (United States)

    Adessi, Alessandra; Cruz de Carvalho, Ricardo; Silvestre, Susana; Rossi, Federico; Mugnai, Gianmarco; Marques da Silva, Jorge; Branquinho, Cristina; De Philippis, Roberto

    2015-04-01

    Biological Soil Crusts (BSCs) are associations between soil particles and varying proportions of cyanobacteria, heterotrophic bacteria, algae, fungi, lichens and mosses. BSCs play a major role in soil stabilization, and in drylands have been well acknowledged for mitigating desertification effects. Amongst the wide diversity of organisms that compose BSCs, cyanobacteria are the first primary producers: they colonize nutrient-limited soils, modifying the micro-environment through the excretion of large amounts of extracellular polymeric substances (EPSs). EPSs represent a huge carbon and nitrogen source for other inhabitants of the crust, are three-dimensionally spread through the first millimeters of the soil, and have a recognized role in influencing the hydrological behavior of the crust. The aim of this study was to investigate the possible role that EPSs play in the physiology of the phototrophic community residing on a light crust (without mosses or lichens, thus mainly inhabited by cyanobacteria and algae). In particular it was investigated whether the three-dimensional matrix in which EPSs are organized allowed light distribution and diffusion inside the crust, thus influencing photosynthesis. Non-invasive techniques were used to extract the polymeric matrix and to analyze photosynthetic performances in native and extracted BSC samples. Preliminary results suggested that the mild extraction protocol allowed to remove a portion of the matrix, and that this treatment revealed highly significant differences in the optical properties of the crusts comparing native and extracted samples. The extraction did not affect cell viability, as samples after the extraction were still photosynthetically active. However, chlorophyll variable fluorescence was significantly lower in the extracted samples than in native ones, and susceptibility to photoinhibition was significantly modified. Evaluating the role of the EPSs in the community is essential to further understand the

  18. Physiology and phylogeny of green sulfur bacteria forming a monospecific phototrophic assemblage at a depth of 100 meters in the Black Sea.

    Science.gov (United States)

    Manske, Ann K; Glaeser, Jens; Kuypers, Marcel M M; Overmann, Jörg

    2005-12-01

    The biomass, phylogenetic composition, and photoautotrophic metabolism of green sulfur bacteria in the Black Sea was assessed in situ and in laboratory enrichments. In the center of the western basin, bacteriochlorophyll e (BChl e) was detected between depths of 90 and 120 m and reached maxima of 54 and 68 ng liter(-1). High-pressure liquid chromatography analysis revealed a dominance of farnesyl esters and the presence of four unusual geranyl ester homologs of BChl e. Only traces of BChl e (8 ng liter(-1)) were found at the northwestern slope of the Black Sea basin, where the chemocline was positioned at a significantly greater depth of 140 m. Stable carbon isotope fractionation values of farnesol indicated an autotrophic growth mode of the green sulfur bacteria. For the first time, light intensities in the Black Sea chemocline were determined employing an integrating quantum meter, which yielded maximum values between 0.0022 and 0.00075 micromol quanta m(-2) s(-1) at the top of the green sulfur bacterial layer around solar noon in December. These values represent by far the lowest values reported for any habitat of photosynthetic organisms. Only one 16S rRNA gene sequence type was detected in the chemocline using PCR primers specific for green sulfur bacteria. This previously unknown phylotype groups with the marine cluster of the Chlorobiaceae and was successfully enriched in a mineral medium containing sulfide, dithionite, and freshly prepared yeast extract. Under precisely controlled laboratory conditions, the enriched green sulfur bacterium proved to be capable of exploiting light intensities as low as 0.015 micromol quanta m(-2) s(-1) for photosynthetic 14CO2 fixation. Calculated in situ doubling times of the green sulfur bacterium range between 3.1 and 26 years depending on the season, and anoxygenic photosynthesis contributes only 0.002 to 0.01% to total sulfide oxidation in the chemocline. The stable population of green sulfur bacteria in the Black Sea

  19. Physiology and Mechanism of Phototrophic Fe(II) Oxidation by Rhodopseudomonas palustris TIE-1

    Science.gov (United States)

    Jiao, Y.; Newman, D.

    2007-12-01

    Phototrophic Fe(II)-oxidizing bacteria use electrons from ferrous iron [Fe(II)] and energy from light to drive reductive CO2 fixation. This metabolism is thought to be ancient in origin, and plays an important role in environmental iron cycling. It has been implicated in the deposition of Banded Iron Formations, a class of ancient sedimentary iron deposits. Consistent with this hypothesis, we discovered that hydrogen gas, a thermodynamically favorable electron donor to Fe(II), in an Archean atmosphere would not have inhibited phototrophic Fe(II) oxidation. To understand this physiology and the connection to BIF formation at the molecular level, the mechanisms of phototrophic Fe(II) oxidation were examined in a model organism Rhodopseudomonas palustris TIE-1. Increased expression of a putative decaheme c-type cytochrome, encoded by pioA, was observed when cells were grown under Fe(II)-oxidizing conditions. Two genes located immediately downstream of pioA in the same operon, pioB and pioC, encode a putative outer membrane beta-barrel protein and a putative high potential iron-sulfur protein, respectively. Deletion studies demonstrated that all three genes are involved in phototrophic Fe(II) oxidation. This study provides our first insight into the molecular mechanisms of this metabolism, which will be further characterized by in vitro biochemical studies.

  20. Description of a redox-controlled sulfidostat for the growth of sulfide-oxidizing phototrophs

    NARCIS (Netherlands)

    Sanchez, O; vanGemerden, H; Mas, J

    1996-01-01

    This paper describes a novel type of continuous culture for the growth of phototrophic sulfur oxidizers under constant concentrations of hydrogen sulfide, The culture maintains a constant concentration of sulfide despite possible variations in external factors likely to affect photosynthetic activit

  1. Changes in tolerance to herbicide toxicity throughout development stages of phototrophic biofilms.

    Science.gov (United States)

    Paule, A; Roubeix, V; Lauga, B; Duran, R; Delmas, F; Paul, E; Rols, J L

    2013-11-15

    Ecotoxicological experiments have been performed in laboratory-scale microcosms to investigate the sensitivity of phototrophic biofilm communities to the alachlor herbicide, in relation to the stages of phototrophic biofilm maturation (age of the phototrophic biofilms) and physical structure (intact biofilm versus recolonization). The phototrophic biofilms were initially cultivated on artificial supports in a prototype rotating annular bioreactor (RAB) with Taylor-Couette type flow under constant operating conditions. Biofilms were collected after 1.6 and 4.4 weeks of culture providing biofilms with different maturation levels, and then exposed to nominal initial alachlor concentration of 10 μg L(-1) in either intact or recolonized biofilms for 15 days in microcosms (mean time-weighted average concentration - TWAC of 5.52 ± 0.74 μg L(-1)). At the end of the exposure period, alachlor effects were monitored by a combination of biomass descriptors (ash-free dry mass - AFDM, chlorophyll a), structural molecular fingerprinting (T-RFLP), carbon utilization spectra (Biolog) and diatom species composition. We found significant effects that in terms of AFDM, alachlor inhibited growth of the intact phototrophic biofilms. No effect of alachlor was observed on diatom composition or functional and structural properties of the bacterial community regardless of whether they were intact or recolonized. The intact three-dimensional structure of the biofilm did not appear to confer protection from the effects of alachlor. Bacterial community structure and biomass level of 4.4 weeks - intact phototrophic biofilms were significantly influenced by the biofilm maturation processes rather than alachlor exposure. The diatom communities which were largely composed of mobile and colonizer life-form populations were not affected by alachlor. This study showed that the effect of alachlor (at initial concentration of 10 μg L(-1) or mean TWAC of 5.52 ± 0.74 μg L(-1)) is mainly limited to

  2. Energy positive domestic wastewater treatment: the roles of anaerobic and phototrophic technologies

    KAUST Repository

    Shoener, B. D.

    2014-01-01

    The negative energy balance of wastewater treatment could be reversed if anaerobic technologies were implemented for organic carbon oxidation and phototrophic technologies were utilized for nutrient recovery. To characterize the potential for energy positive wastewater treatment by anaerobic and phototrophic biotechnologies we performed a comprehensive literature review and analysis, focusing on energy production (as kJ per capita per day and as kJ m-3 of wastewater treated), energy consumption, and treatment efficacy. Anaerobic technologies included in this review were the anaerobic baffled reactor (ABR), anaerobic membrane bioreactor (AnMBR), anaerobic fluidized bed reactor (AFB), upflow anaerobic sludge blanket (UASB), anaerobic sequencing batch reactor (ASBR), microbial electrolysis cell (MEC), and microbial fuel cell (MFC). Phototrophic technologies included were the high rate algal pond (HRAP), photobioreactor (PBR), stirred tank reactor, waste stabilization pond (WSP), and algal turf scrubber (ATS). Average energy recovery efficiencies for anaerobic technologies ranged from 1.6% (MFC) to 47.5% (ABR). When including typical percent chemical oxygen demand (COD) removals by each technology, this range would equate to roughly 40-1200 kJ per capita per day or 110-3300 kJ m-3 of treated wastewater. The average bioenergy feedstock production by phototrophic technologies ranged from 1200-4700 kJ per capita per day or 3400-13000 kJ m-3 (exceeding anaerobic technologies and, at times, the energetic content of the influent organic carbon), with usable energy production dependent upon downstream conversion to fuels. Energy consumption analysis showed that energy positive anaerobic wastewater treatment by emerging technologies would require significant reductions of parasitic losses from mechanical mixing and gas sparging. Technology targets and critical barriers for energy-producing technologies are identified, and the role of integrated anaerobic and phototrophic

  3. A photosynthetic rotating annular bioreactor (Taylor-Couette type flow) for phototrophic biofilm cultures.

    Science.gov (United States)

    Paule, A; Lauga, B; Ten-Hage, L; Morchain, J; Duran, R; Paul, E; Rols, J L

    2011-11-15

    In their natural environment, the structure and functioning of microbial communities from river phototrophic biofilms are driven by biotic and abiotic factors. An understanding of the mechanisms that mediate the community structure, its dynamics and the biological succession processes during phototrophic biofilm development can be gained using laboratory-scale systems operating with controlled parameters. For this purpose, we present the design and description of a new prototype of a rotating annular bioreactor (RAB) (Taylor-Couette type flow, liquid working volume of 5.04 L) specifically adapted for the cultivation and investigation of phototrophic biofilms. The innovation lies in the presence of a modular source of light inside of the system, with the biofilm colonization and development taking place on the stationary outer cylinder (onto 32 removable polyethylene plates). The biofilm cultures were investigated under controlled turbulent flowing conditions and nutrients were provided using a synthetic medium (tap water supplemented with nitrate, phosphate and silica) to favour the biofilm growth. The hydrodynamic features of the water flow were characterized using a tracer method, showing behaviour corresponding to a completely mixed reactor. Shear stress forces on the surface of plates were also quantified by computer simulations and correlated with the rotational speed of the inner cylinder. Two phototrophic biofilm development experiments were performed for periods of 6.7 and 7 weeks with different inoculation procedures and illumination intensities. For both experiments, biofilm biomasses exhibited linear growth kinetics and produced 4.2 and 2.4 mg cm(-)² of ash-free dry matter. Algal and bacterial community structures were assessed by microscopy and T-RFLP, respectively, and the two experiments were different but revealed similar temporal dynamics. Our study confirmed the performance and multipurpose nature of such an innovative photosynthetic bioreactor

  4. Rapid assessment of different oxygenic phototrophs and single-cell photosynthesis with multicolour variable chlorophyll fluorescence imaging

    DEFF Research Database (Denmark)

    Trampe, Erik Christian Løvbjerg; Kolbowski, J.; Schreiber, U.

    2011-01-01

    We present a new system for microscopic multicolour variable chlorophyll fluorescence imaging of aquatic phototrophs. The system is compact and portable and enables microscopic imaging of photosynthetic performance of individual cells and chloroplasts using different combinations of blue, green, ...

  5. Cyanobacteria in Sulfidic Spring Microbial Mats Can Perform Oxygenic and Anoxygenic Photosynthesis Simultaneously during an Entire Diurnal Period

    Science.gov (United States)

    Klatt, Judith M.; de Beer, Dirk; Häusler, Stefan; Polerecky, Lubos

    2016-01-01

    We used microsensors to study the regulation of anoxygenic and oxygenic photosynthesis (AP and OP, respectively) by light and sulfide in a cyanobacterium dominating microbial mats from cold sulfidic springs. Both photosynthetic modes were performed simultaneously over all H2S concentrations (1–2200 μM) and irradiances (4–52 μmol photons m-2 s-1) tested. AP increased with H2S concentration while the sum of oxygenic and anoxygenic photosynthetic rates was constant at each light intensity. Thus, the total photosynthetically driven electron transport rate was solely controlled by the irradiance level. The partitioning between the rates of these two photosynthetic modes was regulated by both light and H2S concentration. The plastoquinone pool (PQ) receives electrons from sulfide:quinone:reductase (SQR) in AP and from photosystem II (PSII) in OP. It is thus the link in the electron transport chain where both pathways intersect, and the compound that controls their partitioning. We fitted our data with a model of the photosynthetic electron transport that includes the kinetics of plastoquinone reduction and oxidation. The model results confirmed that the observed partitioning between photosynthetic modes can be explained by a simple kinetic control based on the affinity of SQR and PSII toward PQ. The SQR enzyme and PSII have similar affinities toward PQ, which explains the concurrent OP and AP over an astonishingly wide range of H2S concentrations and irradiances. The elegant kinetic control of activity makes the cyanobacterium successful in the fluctuating spring environment. We discuss how these specific regulation mechanisms may have played a role in ancient H2S-rich oceans. PMID:28018309

  6. Excess copper induces anoxygenic photosynthesis in Anabaena doliolum: a homology based proteomic assessment of its survival strategy.

    Science.gov (United States)

    Bhargava, Poonam; Mishra, Yogesh; Srivastava, Ashish Kumar; Narayan, Om Prakash; Rai, Lal Chand

    2008-04-01

    This study is the first to demonstrate operation of anoxygenic photosynthesis in copper acclimated Anabaena doliolum and to offer proteomic comparison with the control cells. The Cu-treated control strain showed a negative correlation in growth and intracellular Cu, partial inhibition of O(2)-evolution, PS II, PS I, whole chain, chlorophyll absorption, and nitrogenase activity. However, the acclimated strain growing in 250-fold excess Cu exhibited near normal growth, ATP content, PS I activity, carbon fixation, and almost complete inhibition of O(2)-evolution, PS II and chlorophyll absorption, but increased nitrogenase activity as compared to control. Proteomic decoding of the survival strategy of Cu-treated control and the acclimated strain using two-dimensional gel electrophoresis and MALDI-TOF MS analysis of proteins displaying significant and reproducible changes demonstrated involvement of transketolase, phycoerythrocyanin alpha-chain, iron superoxide dismutase (Fe-SOD), hypothetical protein alr 0803, manganese superoxide dismutase (Mn-SOD), phosphoribulokinase, and plastocyanin (PLC). Expression pattern of these proteins was attested at the transcriptional level using RT-PCR. Time course analysis of proteins of Cu-treated control strain revealed almost no change in PLC level, and a minor accumulation of transketolase, phycoerythrocyanin alpha-chain and both isoforms of SOD after 7 and recovery after 10 days. Acclimated strain under excess Cu, however, exhibited significant accumulation of both isoforms of SOD, plastocyanin, phosphoribulokinase and transketolase, which seem to counteract oxidative damage, serve as an alternate electron carrier from cytochrome b6/f complex to photosystem I and meet the NADPH and ATP requirements, respectively, under anoxygenic photosynthesis. In view of the kinetics of the hypothetical protein alr0803 (no change in expression level for 7, maximum after 10 and decline after 15 days) its involvement in metal homeostasis is

  7. Growth Characteristics of Tetraselmis sp.-1 in Phototrophic, Mixotrophic and Heterotrophic Conditions

    Institute of Scientific and Technical Information of China (English)

    Shen Jihong(沈继红); Yu Junhong; Lin Xuezheng; Li Guangyou; Liu Fayi

    2004-01-01

    Tetraselmis sp.-1 is a new microalgae strain constructed by cell fusion technique. In this paper, the growth characteristics of Tetraselmis sp.-1 under different culture conditions are investigated. The growth kinetic models are obtained, the assimilation of C and NH4+ is investigated and the assimilation efficiency of Tetraselmis sp.-1 under different culture conditions is calculated. The results show that different culture conditions do not have obvious influence on carbon absorbance, but have significant influence on nitrogen absorbance, C∶N is maximum under heterotrophic condition, while minimum under phototrophic condition. The assimilation efficiency (η) of Tetraselmis sp.-1 has the highest value in heterotrophic condition and largely higher than those in phototrophic and mixotrophic conditions.

  8. NATURAL ANTIBIOFOULING AGENTS AS NEW CONTROL METHOD FOR PHOTOTROPHIC BIOFILMS DWELLING ON MONUMENTAL STONE SURFACES

    Directory of Open Access Journals (Sweden)

    Oana-Adriana CUZMAN

    2011-03-01

    Full Text Available Five natural antibiofoulants with terrestrial (capsaicine - CS, cinnamaldehyde - CI and marine origin (zosteric acid - ZA, poly-alkylpyridinium salts - pAPS and Ceramium botryocarpum extract - CBE have been selected and tested against phototrophic biofilm formation on the stone surfaces for their inhibitory properties. The antibiofouling agents (ABAs were incorporated into two commercial silicone based coatings (Silres BS OH 100 - S and Silres BS 290 - W. In this work, phototrophic growth was evaluated by epifluorescence microscopy and semi-quantitative image analysis. The results showed an inhibitory efficiency for almost all tested ABAs. However, this efficiency has been found for short time or when the incorporating agent were incompletely cured. Among the ABAs tested, the poly-alkylpyridinium salts and cinnamaldehyde incorporated into Silres BS 290 showed the best inhibitory efficiency.

  9. Genomic analysis reveals key aspects of prokaryotic symbiosis in the phototrophic consortium "Chlorochromatium aggregatum"

    DEFF Research Database (Denmark)

    Liu, Zhenfeng; Müller, Johannes; Li, Tao;

    2013-01-01

    'Chlorochromatium aggregatum' is a phototrophic consortium, a symbiosis that may represent the highest degree of mutual interdependence between two unrelated bacteria not associated with a eukaryotic host. 'Chlorochromatium aggregatum' is a motile, barrel-shaped aggregate formed from a single cell...... of "Candidatus Symbiobacter mobilis," a polarly flagellated, non-pigmented, heterotrophic bacterium, which is surrounded by approximately 15 epibiont cells of Chlorobium chlorochromatii, a non-motile photolithoautotrophic green sulfur bacterium....

  10. Enhanced algae growth in both phototrophic and mixotrophic culture under blue light.

    Science.gov (United States)

    Das, Probir; Lei, Wang; Aziz, Siti Sarah; Obbard, Jeffrey Philip

    2011-02-01

    Biomass productivity and fatty acid methyl esters (FAME) derived from intracellular lipid of a Nannochloropsis sp. isolated from Singapore's coastal waters were studied under different light wavelengths and intensities. Nannochloropsis sp., was grown in both phototrophic and mixotrophic (glycerol as the carbon source) culture conditions in three primary monochromatic light wavelengths, i.e., red, green and blue LEDs, and also in white LED. The maximum specific growth rate (μ) for LEDs was blue>white>green>red. Nannochloropsis sp. achieved a μ of 0.64 and 0.66 d(-1) in phototrophic and mixotrophic cultures under blue lighting, respectively. The intracellular fatty acid composition of Nannochloropsis sp. varied between cultures exposed to different wavelengths, although the absolute fatty acid content did differ significantly. Maximum FAME yield from Nannochloropsis sp. was 20.45% and 15.11% of dry biomass weight equivalent under photo- and mixotrophic culture conditions respectively for cultures exposed to green LED (550 nm). However, maximum volumetric FAME yield was achieved for phototrophic and mixotrophic cultures (i.e., 55.13 and 111.96 mg/l, respectively) upon cell exposure to blue LED (470 nm) due to highest biomass productivity. It was calculated that incremental exposure of light intensity over the cell growth cycle saves almost 20% of the energy input relative to continuous illumination for a given light intensity.

  11. Light structures phototroph, bacterial and fungal communities at the soil surface.

    Directory of Open Access Journals (Sweden)

    Lawrence O Davies

    Full Text Available The upper few millimeters of soil harbour photosynthetic microbial communities that are structurally distinct from those of underlying bulk soil due to the presence of light. Previous studies in arid zones have demonstrated functional importance of these communities in reducing soil erosion, and enhancing carbon and nitrogen fixation. Despite being widely distributed, comparative understanding of the biodiversity of the soil surface and underlying soil is lacking, particularly in temperate zones. We investigated the establishment of soil surface communities on pasture soil in microcosms exposed to light or dark conditions, focusing on changes in phototroph, bacterial and fungal communities at the soil surface (0-3 mm and bulk soil (3-12 mm using ribosomal marker gene analyses. Microbial community structure changed with time and structurally similar phototrophic communities were found at the soil surface and in bulk soil in the light exposed microcosms suggesting that light can influence phototroph community structure even in the underlying bulk soil. 454 pyrosequencing showed a significant selection for diazotrophic cyanobacteria such as Nostoc punctiforme and Anabaena spp., in addition to the green alga Scenedesmus obliquus. The soil surface also harboured distinct heterotrophic bacterial and fungal communities in the presence of light, in particular, the selection for the phylum Firmicutes. However, these light driven changes in bacterial community structure did not extend to the underlying soil suggesting a discrete zone of influence, analogous to the rhizosphere.

  12. Characteristics of extracellular polymeric substances of phototrophic biofilms at different aquatic habitats.

    Science.gov (United States)

    Fang, Fang; Lu, Wen-Tao; Shan, Qi; Cao, Jia-Shun

    2014-06-15

    Three different phototrophic biofilms obtained from a natural lake (Sample 1), drinking water plant (Sample 2) and wastewater treatment plant (Sample 3) were investigated. Diatoms and green algae were the dominant algae of three biofilms, and the biomass was highest in biofilm of Sample 2. The three phototrophic biofilms also had variable extracellular polymeric substances (EPS) concentrations and compositions. Total EPS concentration of 14.80 mg/g DW was highest in biofilm of Sample 2, followed by biofilms of Samples 3 and 1 (13.11 and 12.29 mg/g DW). Tightly bound EPS (TB-EPS) were the main fraction, and polysaccharides and protein were the main components of total EPS in all three biofilms. However, the compositions of loosely bound EPS (LB-EPS) and TB-EPS were different in three biofilms. Fourier-transform infrared and fluorescence spectra indicated different structure and compositions of LB-EPS and TB-EPS. These results demonstrated the characteristics of EPS produced by phototrophic biofilms varied and had compact relation to their growth environmental conditions.

  13. Gain and loss of phototrophic genes revealed by comparison of two Citromicrobium bacterial genomes.

    Directory of Open Access Journals (Sweden)

    Qiang Zheng

    Full Text Available Proteobacteria are thought to have diverged from a phototrophic ancestor, according to the scattered distribution of phototrophy throughout the proteobacterial clade, and so the occurrence of numerous closely related phototrophic and chemotrophic microorganisms may be the result of the loss of genes for phototrophy. A widespread form of bacterial phototrophy is based on the photochemical reaction center, encoded by puf and puh operons that typically are in a 'photosynthesis gene cluster' (abbreviated as the PGC with pigment biosynthesis genes. Comparison of two closely related Citromicrobial genomes (98.1% sequence identity of complete 16S rRNA genes, Citromicrobium sp. JL354, which contains two copies of reaction center genes, and Citromicrobium strain JLT1363, which is chemotrophic, revealed evidence for the loss of phototrophic genes. However, evidence of horizontal gene transfer was found in these two bacterial genomes. An incomplete PGC (pufLMC-puhCBA in strain JL354 was located within an integrating conjugative element, which indicates a potential mechanism for the horizontal transfer of genes for phototrophy.

  14. Air-dust-borne associations of phototrophic and hydrocarbon-utilizing microorganisms: promising consortia in volatile hydrocarbon bioremediation.

    Science.gov (United States)

    Al-Bader, Dhia; Eliyas, Mohamed; Rayan, Rihab; Radwan, Samir

    2012-11-01

    Aquatic and terrestrial associations of phototrophic and heterotrophic microorganisms active in hydrocarbon bioremediation have been described earlier. The question arises: do similar consortia also occur in the atmosphere? Dust samples at the height of 15 m were collected from Kuwait City air, and analyzed microbiologically for phototrophic and heterotrophic hydrocarbon-utilizing microorganisms, which were subsequently characterized according to their 16S rRNA gene sequences. The hydrocarbon utilization potential of the heterotrophs alone, and in association with the phototrophic partners, was measured quantitatively. The chlorophyte Gloeotila sp. and the two cyanobacteria Nostoc commune and Leptolyngbya thermalis were found associated with dust, and (for comparison) the cynobacteria Leptolyngbya sp. and Acaryochloris sp. were isolated from coastal water. All phototrophic cultures harbored oil vapor-utilizing bacteria in the magnitude of 10(5) g(-1). Each phototrophic culture had its unique oil-utilizing bacteria; however, the bacterial composition in Leptolyngbya cultures from air and water was similar. The hydrocarbon-utilizing bacteria were affiliated with Acinetobacter sp., Aeromonas caviae, Alcanivorax jadensis, Bacillus asahii, Bacillus pumilus, Marinobacter aquaeolei, Paenibacillus sp., and Stenotrophomonas maltophilia. The nonaxenic cultures, when used as inocula in batch cultures, attenuated crude oil in light and dark, and in the presence of antibiotics and absence of nitrogenous compounds. Aqueous and diethyl ether extracts from the phototrophic cultures enhanced the growth of the pertinent oil-utilizing bacteria in batch cultures, with oil vapor as a sole carbon source. It was concluded that the airborne microbial associations may be effective in bioremediating atmospheric hydrocarbon pollutants in situ. Like the aquatic and terrestrial habitats, the atmosphere contains dust-borne associations of phototrophic and heterotrophic hydrocarbon

  15. Photosynthetic Versatility in the Genome of Geitlerinema sp. PCC 9228 (Formerly Oscillatoria limnetica ‘Solar Lake’), a Model Anoxygenic Photosynthetic Cyanobacterium

    OpenAIRE

    2016-01-01

    Anoxygenic cyanobacteria that use sulfide as the electron donor for photosynthesis are a potentially influential but poorly constrained force on Earth’s biogeochemistry. Their versatile metabolism may have boosted primary production and nitrogen cycling in euxinic coastal margins in the Proterozoic. In addition, they represent a biological mechanism for limiting the accumulation of atmospheric oxygen, especially before the Great Oxidation Event and in the low-oxygen conditions of the Proteroz...

  16. Astrobiological implications of dim light phototrophy in deep-sea red clays

    Science.gov (United States)

    Das, Anindita; Singh, Tanya; LokaBharathi, P. A.; Dhakephalkar, Prashant K.; Mallik, Sweta; Kshirsagar, Pranav R.; Khadge, N. H.; Nath, B. Nagender; Bhattacharya, Satadru; Dagar, Aditya Kumar; Kaur, Prabhjot; Ray, Dwijesh; Shukla, Anil D.; Fernandes, Christabelle E. G.; Fernandes, Sheryl O.; Thomas, Tresa Remya A.; Mamatha, s. S.; Mourya, Babu Shashikant; Meena, Ram Murti

    2017-02-01

    Red clays of Central Indian Basin (CIB) under influence of trace of Rodriguez Triple Junction exhibited chemoautotrophy, low temperature hydrothermal alterations and photoautotrophic potential. Seamount flank TVBC-08, hosting such signatures revealed dominance of aerobic anoxygenic phototroph Erythrobacter, with 93% of total 454 pyrosequencing tags. Subsequently, enrichments for both aerobic (Erythrobacter) and anaerobic anoxygenic phototrophs (green and purple sulphur bacteria) under red and white LED light illumination, with average irradiance 30.66 W m-2, were attempted for three red-clay sediment cores. Successful enrichments were obtained after incubation for c.a. 120 days at 4°± 2 °C and 25°± 2 °C, representing ambient psychrophilic and low temperature hydrothermal alteration conditions respectively. During hydrothermal cooling, a microbial succession from anaerobic chemolithotrophy to oxygenic photoautotrophy through anaerobic/aerobic anoxygenic phototrophic microbes is indicated. Spectral absorbance patterns of the methanol extracted cell pellets showed peaks corresponding to metal sulphide precipitations, the Soret band of chlorosome absorbance by photosystem II and absence of peaks at Qy transition band. Dendritic nano-structures of metal sulphides are common in these sediments and are comparable with other sulphidic paleo-marine Martian analogues. Significant blue and redshifts have been observed for the experimental samples relative to the un-inoculated medium. These observations indicate the propensity of metal-sulphide deposits contributing to chemiluminiscence supporting the growth of phototrophs at least partially, in the otherwise dark abyss. The effects of other geothermal heat and light sources are also under further consideration. The potential of phototrophic microbial cells to exhibit Doppler shift in absorbance patterns is significant towards understanding planetary microbial habitability. Planetary desiccation could considerably

  17. Environmental drivers of phototrophic biofilms in an Alpine show cave (SW-Italian Alps)

    Energy Technology Data Exchange (ETDEWEB)

    Piano, E., E-mail: elena.piano@unito.it [Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin (Italy); Bona, F.; Falasco, E. [Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin (Italy); La Morgia, V. [ISPRA, via Ca' Fornacetta, 9, 40064 Ozzano dell' Emilia (Italy); Badino, G. [Department of Physics, University of Turin, Via P. Giuria 1, 10125 Turin (Italy); Isaia, M. [Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin (Italy)

    2015-12-01

    The proliferation of lampenflora is a major threat for the conservation of show caves, since phototrophic organisms cause physical, chemical and aesthetic damage to speleothems. In this paper we examine the environmental factors influencing the presence and the growth of the three main photosynthetic groups composing phototrophic biofilms in the Bossea show cave (SW-Italian Alps). The presence and the primary production of cyanobacteria, diatoms and green algae were detected with BenthoTorch®, an instrument for in situ measurement of chlorophyll a concentration that has never been used before in caves. By means of different techniques of regression analysis, we highlighted the response of the three photosynthetic groups to different environmental factors. Illuminance proved to be the main factor influencing positively both the probability of the presence and the productivity of the three groups. The presence of seeping water on the substrate and the distance from the cave entrance proved to play an important role in determining patterns of colonization. By means of GIS techniques, we provide thematic maps of the cave, providing a representation of pattern of the density of the three examined photosynthetic groups within different areas of the cave. The same approach may apply to other show caves, aiming at providing suggestions for the cave management (i.e. cleaning of the cave walls and positioning of artificial lights) and reduce impact caused by tourism. - Highlights: • We used a PAM fluorimeter on autotrophic biofilms in a show cave for the first time. • We modelled the environmental factors influencing phototrophic biofilms. • Illuminance, moisture and distance from the entrance proved to be significant. • We produced thematic maps illustrating our results. • We provide suggestions for cave management.

  18. Maleimides (1 H-pyrrole-2,5-diones) as molecular indicators of anoxygenic photosynthesis in ancient water columns

    Science.gov (United States)

    Grice, Kliti; Gibbison, Robert; Atkinson, Jane E.; Schwark, Lorenz; Eckardt, Christian B.; Maxwell, James R.

    1996-10-01

    Maleimides (1 H-pyrrole-2,5-diones), degradation products of photosynthetic tetrapyrrole pigments, have been found for the first time in the polar fraction of the solvent extracts of two marine sediments deposited in restricted basins: Kupferschiefer (Permian) and Serpiano shale (Mid-Triassic). GC and GC—MS analyses of the TBDMS ( tertiary-butyldimethylsilyl) derivatives show a simple component distribution, dominated by Me Et maleimide, mainly of planktonic origin; Me n-Pr and Me i-Bu maleimides, present in low abundance, are thought on structural grounds to be derived from the bacteriochlorophylls c, d, or e of Chlorobiaceae (anoxygenic green sulfur bacteria). This is confirmed for Kupferschiefer by isotope ratio monitoring (irm) GCMS which shows them to be enriched in 13C as a result of their photosynthetic carbon assimilation, which takes place by the reversed tricarboxylic acid (TCA) cycle. The structurally more specific Me i-Bu maleimide is, however, slightly more enriched in 13C than Me n-Pr maleimide, suggesting that the latter is derived in part from reduction of the C 3-acid substituent at C-17 of phytoplanktonic chlorophyll. These results provide evidence for the existence in both depositional settings of microbial communities containing Chlorobiaceae. In turn, this indicates that there must have been periods when the water column was highly stratified and anoxia extended into the zone of light penetration.

  19. Production and consumption of hydrogen in hot spring microbial mats dominated by a filamentous anoxygenic photosynthetic bacterium.

    Science.gov (United States)

    Otaki, Hiroyo; Everroad, R Craig; Matsuura, Katsumi; Haruta, Shin

    2012-01-01

    Microbial mats containing the filamentous anoxygenic photosynthetic bacterium Chloroflexus aggregans develop at Nakabusa hot spring in Japan. Under anaerobic conditions in these mats, interspecies interaction between sulfate-reducing bacteria as sulfide producers and C. aggregans as a sulfide consumer has been proposed to constitute a sulfur cycle; however, the electron donor utilized for microbial sulfide production at Nakabusa remains to be identified. In order to determine this electron donor and its source, ex situ experimental incubation of mats was explored. In the presence of molybdate, which inhibits biological sulfate reduction, hydrogen gas was released from mat samples, indicating that this hydrogen is normally consumed as an electron donor by sulfate-reducing bacteria. Hydrogen production decreased under illumination, indicating that C. aggregans also functions as a hydrogen consumer. Small amounts of hydrogen may have also been consumed for sulfur reduction. Clone library analysis of 16S rRNA genes amplified from the mats indicated the existence of several species of hydrogen-producing fermentative bacteria. Among them, the most dominant fermenter, Fervidobacterium sp., was successfully isolated. This isolate produced hydrogen through the fermentation of organic carbon. Dispersion of microbial cells in the mats resulted in hydrogen production without the addition of molybdate, suggesting that simultaneous production and consumption of hydrogen in the mats requires dense packing of cells. We propose a cyclic electron flow within the microbial mats, i.e., electron flow occurs through three elements: S (elemental sulfur, sulfide, sulfate), C (carbon dioxide, organic carbon) and H (di-hydrogen, protons).

  20. Modeling the Habitat Range of Phototrophic Microorganisms in Yellowstone National Park: Toward the Development of a Comprehensive Fitness Landscape

    Directory of Open Access Journals (Sweden)

    Eric eBoyd

    2012-06-01

    Full Text Available The extent to which geochemical variation constrains the distribution of phototrophic metabolisms was modeled based on 439 observations in geothermal springs in Yellowstone National Park (YNP, Wyoming. Generalized additive models (GAMs were developed to predict the distribution of photosynthesis as a function of spring temperature, pH, and total sulfide. GAMs comprised of temperature explained 42.7% of the variation in the distribution of phototrophic metabolisms whereas GAMs comprised of sulfide and pH explained 20.7% and 11.7% of the variation, respectively. These results suggest that of the measured variables, temperature is the primary constraint on the distribution of phototrophic metabolism in YNP. GAMs comprised of multiple variables explained a larger percentage of the variation in the distribution of phototrophic metabolism, indicating additive interactions among variables. A GAM that combined temperature and sulfide explained the greatest variation in the dataset (54.8% while minimizing the introduction of degrees of freedom. In an effort to verify the extent to which phototroph distribution reflects constraints on activity, we examined the influence of sulfide and temperature on dissolved inorganic carbon (DIC uptake rates under both light and dark conditions. Light-driven DIC uptake decreased systematically with increasing concentrations of sulfide in acidic, algal-dominated systems, but was unaffected in alkaline, bacterial-dominated systems. In both alkaline and acidic systems, light-driven DIC uptake was suppressed in cultures incubated at temperatures 10°C greater than their in situ temperature. Collectively, these results suggest that the habitat range of phototrophs in YNP springs, specifically that of cyanobacteria and algae, largely results from constraints imposed by temperature and sulfide on the activity and fitness of these populations, a finding that is consistent with the predictions from GAMs.

  1. Aerobic landfill bioreactor

    Science.gov (United States)

    Hudgins, Mark P; Bessette, Bernard J; March, John; McComb, Scott T.

    2000-01-01

    The present invention includes a method of decomposing municipal solid waste (MSW) within a landfill by converting the landfill to aerobic degradation in the following manner: (1) injecting air via the landfill leachate collection system (2) injecting air via vertical air injection wells installed within the waste mass; (3) applying leachate to the waste mass using a pressurized drip irrigation system; (4) allowing landfill gases to vent; and (5) adjusting air injection and recirculated leachate to achieve a 40% to 60% moisture level and a temperature between 120.degree. F. and 140.degree. F. in steady state.

  2. Oxygen suppresses light-driven anodic current generation by a mixed phototrophic culture.

    Science.gov (United States)

    Darus, Libertus; Ledezma, Pablo; Keller, Jürg; Freguia, Stefano

    2014-12-02

    This paper describes the detrimental effect of photosynthetically evolved oxygen on anodic current generation in the presence of riboflavin upon illumination of a mixed phototrophic culture enriched from a freshwater pond at +0.6 V vs standard hydrogen electrode. In the presence of riboflavin, the phototrophic biomass in the anodic compartment produced an electrical current in response to light/dark cycles (12 h/12 h) over 12 months of operation, generating a maximum current density of 17.5 mA x m(-2) during the dark phase, whereas a much lower current of approximately 2 mA x m(-2) was generated during illumination. We found that the low current generation under light exposure was caused by high rates of reoxidation of reduced riboflavin by oxygen produced during photosynthesis. Quantification of biomass by fluorescence in situ hybridization images suggested that green algae were predominant in both the anode-based biofilm (55.1%) and the anolyte suspension (87.9%) with the remaining biovolume accounted for by bacteria. Genus-level sequencing analysis revealed that bacteria were dominated by cyanobacterium Leptolyngbia (∼35%), while the prevailing algae were Dictyosphaerium, Coelastrum, and Auxenochlorella. This study offers a key comprehension of mediator sensitivity to reoxidation by dissolved oxygen for improvement of microbial solar cell performance.

  3. Eukaryotic microbial diversity of phototrophic microbial mats in two Icelandic geothermalhot springs.

    Science.gov (United States)

    Aguilera, Angeles; Souza-Egipsy, Virginia; González-Toril, Elena; Rendueles, Olaya; Amils, Ricardo

    2010-03-01

    The composition of the eukaryotic community and the three-dimensional structure of diverse phototrophic microbial mats from two hot springs in Iceland (Seltun and Hveradalir geothermal areas) were explored by comparing eukaryotic assemblages from microbial mats. Samples were collected in July 2007 from 15 sampling stations along thermal and pH gradients following both hot springs. Physicochemical data revealed high variability in terms of pH (ranging from 2.8 to 7), with high concentrations of heavy metals, including up to 20 g Fe/l, 80 mg Zn/l, 117 mg Cu/l, and 39 mg Ni/l at the most acidic sampling points. Phylogenetic analysis of 18S rDNA genes revealed a diversity of sequences related to several taxa, including members of the Bacillariophyta, Chlorophyta, Rhodophyta, and Euglenophyta phyla as well as ciliates, amoebae, and stramenopiles. The closest relatives to some of the sequences detected came from acidophilic organisms, even when the samples were collected at circumneutral water locations. Electron microscopy showed that most of the microecosystems analyzed were organized as phototrophic microbial mats in which filamentous cyanobacteria usually appeared as a major component. Deposits of amorphous minerals rich in silica, iron, and aluminium around the filaments were frequently detected.

  4. Phototrophic phylotypes dominate mesothermal microbial mats associated with hot springs in Yellowstone National Park.

    Science.gov (United States)

    Ross, Kimberly A; Feazel, Leah M; Robertson, Charles E; Fathepure, Babu Z; Wright, Katherine E; Turk-Macleod, Rebecca M; Chan, Mallory M; Held, Nicole L; Spear, John R; Pace, Norman R

    2012-07-01

    The mesothermal outflow zones (50-65°C) of geothermal springs often support an extensive zone of green and orange laminated microbial mats. In order to identify and compare the microbial inhabitants of morphologically similar green-orange mats from chemically and geographically distinct springs, we generated and analyzed small-subunit ribosomal RNA (rRNA) gene amplicons from six mesothermal mats (four previously unexamined) in Yellowstone National Park. Between three and six bacterial phyla dominated each mat. While many sequences bear the highest identity to previously isolated phototrophic genera belonging to the Cyanobacteria, Chloroflexi, and Chlorobi phyla, there is also frequent representation of uncultured, unclassified members of these groups. Some genus-level representatives of these dominant phyla were found in all mats, while others were unique to a single mat. Other groups detected at high frequencies include candidate divisions (such as the OP candidate clades) with no cultured representatives or complete genomes available. In addition, rRNA genes related to the recently isolated and characterized photosynthetic acidobacterium "Candidatus Chloracidobacterium thermophilum" were detected in most mats. In contrast to microbial mats from well-studied hypersaline environments, the mesothermal mats in this study accrue less biomass and are substantially less diverse, but have a higher proportion of known phototrophic organisms. This study provides sequences appropriate for accurate phylogenetic classification and expands the molecular phylogenetic survey of Yellowstone microbial mats.

  5. Bioengineering and Coordination of Regulatory Networks and Intracellular Complexes to Maximize Hydrogen Production by Phototrophic Microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Tabita, F. Robert [The Ohio State University

    2013-07-30

    In this study, the Principal Investigator, F.R. Tabita has teemed up with J. C. Liao from UCLA. This project's main goal is to manipulate regulatory networks in phototrophic bacteria to affect and maximize the production of large amounts of hydrogen gas under conditions where wild-type organisms are constrained by inherent regulatory mechanisms from allowing this to occur. Unrestrained production of hydrogen has been achieved and this will allow for the potential utilization of waste materials as a feed stock to support hydrogen production. By further understanding the means by which regulatory networks interact, this study will seek to maximize the ability of currently available “unrestrained” organisms to produce hydrogen. The organisms to be utilized in this study, phototrophic microorganisms, in particular nonsulfur purple (NSP) bacteria, catalyze many significant processes including the assimilation of carbon dioxide into organic carbon, nitrogen fixation, sulfur oxidation, aromatic acid degradation, and hydrogen oxidation/evolution. Moreover, due to their great metabolic versatility, such organisms highly regulate these processes in the cell and since virtually all such capabilities are dispensable, excellent experimental systems to study aspects of molecular control and biochemistry/physiology are available.

  6. Exploring the secrets of the three-dimensional architecture of phototrophic biofilms in caves

    Directory of Open Access Journals (Sweden)

    Roldàn Monica

    2009-01-01

    Full Text Available Caves with dim natural light, and lighted hypogean environments, have been found to host phototrophic microorganisms from varioustaxonomic groups. These microorganisms group themselves into assemblies known as communities or biofilms, which are associated withrock surfaces. In this work, the phototrophic biofilms that colonise speleothems, walls and floors in three tourist caves (Spain were studied.Confocal laser scanning microscopy (CLSM and scanning electron microscopy (SEM were used to study these organisms and acquirethree-dimensional data on their biofilm structure. CLSM was used in a multi-channel mode whereby the different channels map individualbiofilm components. Cyanobacteria, green microalgae, diatoms, mosses and lichens were found to be grouped as biofilms that differedaccording to the sampling sites. The biofilms were classified into six types regarding their environmental conditions. These types weredefined by their constituent organisms, the thickness of their photosynthetic layers and their structure. Light-related stress is associated with lower biofilm thickness and species diversity, as is low humidity, and, in the case of artificially illuminated areas, the duration of lightexposure.

  7. Different carbon isotope fractionation patterns during the development of phototrophic freshwater and marine biofilms

    Directory of Open Access Journals (Sweden)

    M. Staal

    2007-08-01

    Full Text Available Natural phototrophic biofilms are influenced by a broad array of abiotic and biotic factors and vary over temporal and spatial scales. Different developmental stages can be distinguished and growth rates will vary due to the thickening of the biofilm, which is expected to lead to a limitation of light or mass transport. This study shows that variation in CO2(aq availability leads to a fractionation shift and thereby affects δ13C signatures during biofilm development. For phototrophic freshwater biofilms it was found that the δ13C value became less negative with the thickening of the biofilm, while the opposite trend was found in marine biofilms. Modeling and pH profiling indicated that the trend in the freshwater system was caused by an increase in CO2(aq limitation resulting in an increase of HCO3 as C-source. The opposite trend in the marine system could be explained by a higher heterotrophic biomass and activity causing a higher carbon recycling and thereby lower δ13C values. We conclude that δ13C was more related to the net areal photosynthesis rate and carbon recycling, rather than to the growth rate of the biofilms.

  8. Carbon metabolic pathways in phototrophic bacteria and their broader evolutionary implications

    Directory of Open Access Journals (Sweden)

    Kuo-Hsiang eTang

    2011-08-01

    Full Text Available Photosynthesis is the biological process that converts solar energy to biomass, bio-products and biofuel. It is the only major natural solar energy storage mechanism on Earth. To satisfy the increased demand for sustainable energy sources and identify the mechanism of photosynthetic carbon assimilation, which is one of the bottlenecks in photosynthesis, it is essential to understand the process of solar energy storage and associated carbon metabolism in photosynthetic organisms. Researchers have employed physiological studies, microbiological chemistry, enzyme assays, genome sequencing, transcriptomics, and 13C-based metabolomics/fluxomics to investigate central carbon metabolism and enzymes that operate in phototrophs. In this report, we review diverse CO2 assimilation pathways, acetate assimilation, carbohydrate catabolism, the TCA cycle and some key and/or unconventional enzymes in central carbon metabolism of phototrophic microorganisms. We also discuss the reducing equivalent flow during photoautotrophic and photoheterotrophic growth, evolutionary links in the central carbon metabolic network, and correlations between photosynthetic and non-photosynthetic organisms. Considering the metabolic versatility in these fascinating and diverse photosynthetic bacteria, many essential questions in their central carbon metabolism still remain to be addressed.

  9. Isolation and Identification of Phototrophic Microorganisms from Rudkhan Castle as a Biodeteriorating Agent

    Directory of Open Access Journals (Sweden)

    Parisa Mohammadi

    2016-09-01

    Full Text Available Introduction: Phototrophic microorganisms are the first residents of different surfaces of ancient buildings’ walls. These organisms can expand to provide the colonization of other microorganisms and to form microbial biofilms. During biofilm growth, acids and metabolites production bore the substratum and cause surfaces damages. Rudkan Castle, the historic monument located in Gilan province, an area with a humid climate has an appropriate surfaces to grow these microorganisms. Materials and methods: In this study, morphological identification of algae and cyanobacteria which was isolated from different areas of the brick walls of Castle has been investigated. Samples were taken from 24 different areas of Castle walls and were aseptically cultured into Blue Green Medium (BGM and Bolds Basal Medium (BBM, and colonies were observed using light microscopy. Results: The dominant organisms which were isolated and identified, were Cladophora, Trentepohlia, Klebsormidium, Trebouxia, Pleurastrum, Chlorococcum as chlorophyta order and Scytonema, Tolypothrix, Leptolyngbya, Plectolyngbya, Phormidium, Gloeocapsa, Microcoleus, Nostoc as a cyanobacteria order. Discussion and conclusion: As expected, diversity of a large number of cyanobacteria and algae phototrophs was isolated. Diversity of organisms on the surface of monuments depends on many factors, including the weather condition such as moisture, the amount of radiation absorbed by the surface, temperature of area, the materials used in the monuments, the biological acceptance of surface and presence of variety of organisms in the soil surface and the air on. Study of destructive factors is the first step toward the protection and restoration of ancient monuments.

  10. Nutrient Removal and Biomass Production in an Outdoor Pilot-Scale Phototrophic Biofilm Reactor for Effluent Polishing

    NARCIS (Netherlands)

    Boelee, N.C.; Janssen, M.; Temmink, H.; Shrestha, R.; Buisman, C.J.N.; Wijffels, R.H.

    2014-01-01

    An innovative pilot-scale phototrophic biofilm reactor was evaluated over a 5-month period to determine its capacity to remove nitrogen and phosphorus from Dutch municipal wastewater effluents. The areal biomass production rate ranged between 2.7 and 4.5 g dry weight/m2/day. The areal nitrogen and p

  11. Soil surface colonization by phototrophic indigenous organisms, in two contrasted soils treated by formulated maize herbicide mixtures.

    Science.gov (United States)

    Joly, Pierre; Misson, Benjamin; Perrière, Fanny; Bonnemoy, Frédérique; Joly, Muriel; Donnadieu-Bernard, Florence; Aguer, Jean-Pierre; Bohatier, Jacques; Mallet, Clarisse

    2014-11-01

    Soil phototrophic microorganisms, contributors to soil health and food webs, share their particular metabolism with plants. Current agricultural practices employ mixtures of pesticides to ensure the crops yields and can potentially impair these non-target organisms. However despite this environmental reality, studies dealing the susceptibility of phototrophic microorganisms to pesticide mixtures are scarce. We designed a 3 months microcosm study to assess the ecotoxicity of realistic herbicide mixtures of formulated S-metolachlor (Dual Gold Safeneur(®)), mesotrione (Callisto(®)) and nicosulfuron (Milagro(®)) on phototrophic communities of two soils (Limagne vertisol and Versailles luvisol). The soils presented different colonizing communities, with diatoms and chlorophyceae dominating communities in Limagne soil and cyanobacteria and bryophyta communities in Versailles soil. The results highlighted the strong impairment of Dual Gold Safeneur(®) treated microcosms on the biomass and the composition of both soil phototrophic communities, with no resilience after a delay of 3 months. This study also excluded any significant mixture effect on these organisms for Callisto(®) and Milagro(®) herbicides. We strongly recommend carrying on extensive soil studies on S-metolachlor and its commercial formulations, in order to reconsider its use from an ecotoxicological point of view.

  12. Impact of a simulated oil spill on benthic phototrophs and nitrogen-fixing bacteria in mudflat mesocosms

    NARCIS (Netherlands)

    Chronopoulou, P.-M.; Fahy, A.; Coulon, F.; Païssé, S.; Goñi-Urriza, M.; Peperzak, L.; Acuña Alvarez, L.; McKew, B.A.; Lawson, T.; Timmis, K.N.; Duran, R.; Underwood, G.J.C.; McGenity, T.J.

    2013-01-01

    Coastal and estuarine ecosystems are highly susceptible to crude oil pollution. Therefore, in order to examine the resilience of benthic phototrophs that are pivotal to coastal ecosystem functioning, we simulated an oil spill in tidal mesocosms consisting of intact sediment cores from a mudflat at t

  13. Photosynthetic versatility in the genome of Geitlerinema sp. PCC 9228 (formerly Oscillatoria limnetica ‘Solar Lake’, a model anoxygenic photosynthetic cyanobacterium

    Directory of Open Access Journals (Sweden)

    Sharon L Grim

    2016-10-01

    Full Text Available Anoxygenic cyanobacteria that use sulfide as the electron donor for photosynthesis are a potentially influential but poorly constrained force on Earth’s biogeochemistry. Their versatile metabolism may have boosted primary production and nitrogen cycling in euxinic coastal margins in the Proterozoic. In addition, they represent a biological mechanism for limiting the accumulation of atmospheric oxygen, especially before the Great Oxidation Event and in the low-oxygen conditions of the Proterozoic. In this study, we describe the draft genome sequence of Geitlerinema sp. PCC 9228, formerly Oscillatoria limnetica ‘Solar Lake’, a mat-forming diazotrophic cyanobacterium that can switch between oxygenic photosynthesis and sulfide-based anoxygenic photosynthesis. Geitlerinema possesses three variants of psbA, which encodes protein D1, a core component of the photosystem II reaction center. Phylogenetic analyses indicate that one variant is closely affiliated with cyanobacterial psbA genes that code for a D1 protein used for oxygen-sensitive processes. Another version is phylogenetically similar to cyanobacterial psbA genes that encode D1 proteins used under microaerobic conditions, and the third variant may be cued to high light and/or elevated oxygen concentrations. Geitlerinema has the canonical gene for sulfide quinone reductase (SQR used in cyanobacterial anoxygenic photosynthesis and a putative transcriptional regulatory gene in the same operon. Another operon with a second, distinct sqr and regulatory gene is present, and is phylogenetically related to sqr genes used for high sulfide concentrations. The genome has a comprehensive nif gene suite for nitrogen fixation, supporting previous observations of nitrogenase activity. Geitlerinema possesses a bidirectional hydrogenase rather than the uptake hydrogenase typically used by cyanobacteria in diazotrophy. Overall, the genome sequence of Geitlerinema sp. PCC 9228 highlights potential

  14. Molecular evolution of the nif gene cluster carrying nifI1 and nifI2 genes in the Gram-positive phototrophic bacterium Heliobacterium chlorum.

    Science.gov (United States)

    Enkh-Amgalan, Jigjiddorj; Kawasaki, Hiroko; Seki, Tatsuji

    2006-01-01

    A major nif cluster was detected in the strictly anaerobic, Gram-positive phototrophic bacterium Heliobacterium chlorum. The cluster consisted of 11 genes arranged within a 10 kb region in the order nifI1, nifI2, nifH, nifD, nifK, nifE, nifN, nifX, fdx, nifB and nifV. The phylogenetic position of Hbt. chlorum was the same in the NifH, NifD, NifK, NifE and NifN trees; Hbt. chlorum formed a cluster with Desulfitobacterium hafniense, the closest neighbour of heliobacteria based on the 16S rRNA phylogeny, and two species of the genus Geobacter belonging to the Deltaproteobacteria. Two nifI genes, known to occur in the nif clusters of methanogenic archaea between nifH and nifD, were found upstream of the nifH gene of Hbt. chlorum. The organization of the nif operon and the phylogeny of individual and concatenated gene products showed that the Hbt. chlorum nif operon carrying nifI genes upstream of the nifH gene was an intermediate between the nif operon with nifI downstream of nifH (group II and III of the nitrogenase classification) and the nif operon lacking nifI (group I). Thus, the phylogenetic position of Hbt. chlorum nitrogenase may reflect an evolutionary stage of a divergence of the two nitrogenase groups, with group I consisting of the aerobic diazotrophs and group II consisting of strictly anaerobic prokaryotes.

  15. Feeding by phototrophic red-tide dinoflagellates on the ubiquitous marine diatom Skeletonema costatum.

    Science.gov (United States)

    Du Yoo, Yeong; Jeong, Hae Jin; Kim, Mi Seon; Kang, Nam Seon; Song, Jae Yoon; Shin, Woongghi; Kim, Kwang Young; Lee, Kitack

    2009-01-01

    We investigated feeding by phototrophic red-tide dinoflagellates on the ubiquitous diatom Skeletonema costatum to explore whether dinoflagellates are able to feed on S. costatum, inside the protoplasm of target dinoflagellate cells observed under compound microscope, confocal microscope, epifluorescence microscope, and transmission electron microscope (TEM) after adding living and fluorescently labeled S. costatum (FLSc). To explore effects of dinoflagellate predator size on ingestion rates of S. costatum, we measured ingestion rates of seven dinoflagellates at a single prey concentration. In addition, we measured ingestion rates of the common phototrophic dinoflagellates Prorocentrum micans and Gonyaulax polygramma on S. costatum as a function of prey concentration. We calculated grazing coefficients by combining field data on abundances of P. micans and G. polygramma on co-occurring S. costatum with laboratory data on ingestion rates obtained in the present study. All phototrophic dinoflagellate predators tested (i.e. Akashiwo sanguinea, Amphidinium carterae, Alexandrium catenella, Alexandrium tamarense, Cochlodinium polykrikoides, G. polygramma, Gymnodinium catenatum, Gymnodinium impudicum, Heterocapsa rotundata, Heterocapsa triquetra, Lingulodinium polyedrum, Prorocentrum donghaiense, P. micans, Prorocentrum minimum, Prorocentrum triestinum, and Scrippsiella trochoidea) were able to ingest S. costatum. When mean prey concentrations were 170-260 ng C/ml (i.e. 6,500-10,000 cells/ml), the ingestion rates of G. polygramma, H. rotundata, H. triquetra, L. polyedrum, P. donghaiense, P. micans, and P. triestinum on S. costatum (0.007-0.081 ng C/dinoflagellate/d [0.2-3.0 cells/dinoflagellate/d]) were positively correlated with predator size. With increasing mean prey concentration of ca 1-3,440 ng C/ml (40-132,200 cells/ml), the ingestion rates of P. micans and G. polygramma on S. costatum continuously increased. At the given prey concentrations, the maximum ingestion

  16. The Epsomitic Phototrophic Microbial Mat of Hot Lake, Washington. Community Structural Responses to Seasonal Cycling

    Energy Technology Data Exchange (ETDEWEB)

    Lindemann, Stephen R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Moran, James J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stegen, James C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Renslow, Ryan S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hutchison, Janine R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cole, Jessica K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dohnalkova, Alice [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tremblay, Julien [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Singh, Kanwar [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Malfatti, Stephanie [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chen, Feng [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Tringe, Susannah [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Beyenal, Haluk [Washington State Univ., Pullman, WA (United States); Fredrickson, Jim K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-11-13

    Phototrophic microbial mats are compact ecosystems composed of highly interactive organisms in which energy and element cycling take place over millimeter-to-centimeter-scale distances. Although microbial mats are common in hypersaline environments, they have not been extensively characterized in systems dominated by divalent ions. Hot Lake is a meromictic, epsomitic lake that occupies a small, endorheic basin in north-central Washington. The lake harbors a benthic, phototrophic mat that assembles each spring, disassembles each fall, and is subject to greater than tenfold variation in salinity (primarily Mg2+ and SO2-4) and irradiation over the annual cycle. We examined spatiotemporal variation in the mat community at five time points throughout the annual cycle with respect to prevailing physicochemical parameters by amplicon sequencing of the V4 region of the 16S rRNA gene coupled to near-full-length 16S RNA clone sequences. The composition of these microbial communities was relatively stable over the seasonal cycle and included dominant populations of Cyanobacteria, primarily a group IV cyanobacterium (Leptolyngbya), and Alphaproteobacteria (specifically, members of Rhodobacteraceae and Geminicoccus). Members of Gammaproteobacteria (e.g., Thioalkalivibrio and Halochromatium) and Deltaproteobacteria (e.g., Desulfofustis) that are likely to be involved in sulfur cycling peaked in summer and declined significantly by mid-fall, mirroring larger trends in mat community richness and evenness. Phylogenetic turnover analysis of abundant phylotypes employing environmental metadata suggests that seasonal shifts in light variability exert a dominant influence on the composition of Hot Lake microbial mat communities. The seasonal development and organization of these structured microbial mats provide opportunities for analysis of the temporal and physical dynamics that feed back to community function.

  17. The diversity of cyanobacterial metabolism: genome analysis of multiple phototrophic microorganisms

    Directory of Open Access Journals (Sweden)

    Beck Christian

    2012-02-01

    Full Text Available Abstract Background Cyanobacteria are among the most abundant organisms on Earth and represent one of the oldest and most widespread clades known in modern phylogenetics. As the only known prokaryotes capable of oxygenic photosynthesis, cyanobacteria are considered to be a promising resource for renewable fuels and natural products. Our efforts to harness the sun's energy using cyanobacteria would greatly benefit from an increased understanding of the genomic diversity across multiple cyanobacterial strains. In this respect, the advent of novel sequencing techniques and the availability of several cyanobacterial genomes offers new opportunities for understanding microbial diversity and metabolic organization and evolution in diverse environments. Results Here, we report a whole genome comparison of multiple phototrophic cyanobacteria. We describe genetic diversity found within cyanobacterial genomes, specifically with respect to metabolic functionality. Our results are based on pair-wise comparison of protein sequences and concomitant construction of clusters of likely ortholog genes. We differentiate between core, shared and unique genes and show that the majority of genes are associated with a single genome. In contrast, genes with metabolic function are strongly overrepresented within the core genome that is common to all considered strains. The analysis of metabolic diversity within core carbon metabolism reveals parts of the metabolic networks that are highly conserved, as well as highly fragmented pathways. Conclusions Our results have direct implications for resource allocation and further sequencing projects. It can be extrapolated that the number of newly identified genes still significantly increases with increasing number of new sequenced genomes. Furthermore, genome analysis of multiple phototrophic strains allows us to obtain a detailed picture of metabolic diversity that can serve as a starting point for biotechnological

  18. The Epsomitic Phototrophic Microbial Mat of Hot Lake, Washington: Community Structural Responses to Seasonal Cycling

    Directory of Open Access Journals (Sweden)

    Stephen R Lindemann

    2013-11-01

    Full Text Available Phototrophic microbial mats are compact ecosystems composed of highly interactive organisms in which energy and element cycling take place over millimeter-to-centimeter-scale distances. Although microbial mats are common in hypersaline environments, they have not been extensively characterized in systems dominated by divalent ions. Hot Lake is a meromictic, epsomitic lake that occupies a small, endorheic basin in north-central Washington. The lake harbors a benthic, phototrophic mat that assembles each spring and disassembles each fall and is subject to greater than tenfold variation in salinity (primarily Mg2+ and SO42- and irradiation over the annual cycle. We examined spatiotemporal variation in the mat community at five time points throughout the annual cycle with respect to prevailing physicochemical parameters by sequencing the V4 region of the 16S rRNA gene coupled to near-full-length 16S RNA clone sequences. The composition of these microbial communities was relatively stable over the seasonal cycle and included dominant populations of Cyanobacteria, primarily a group IV cyanobacterium (Leptolyngbya, and Alphaproteobacteria (specifically, members of Rhodobacteraceae and Geminicoccus. Members of Gammaproteobacteria (e.g., Thioalkalivibrio and Halochromatium and Deltaproteobacteria (e.g., Desulfofustis that are likely to be involved in sulfur cycling peaked in summer and declined significantly by mid-fall, mirroring larger trends in mat community richness and evenness. Phylogenetic turnover analysis of abundant phylotypes employing environmental metadata suggests that seasonal shifts in light variability exert a dominant influence on the composition of Hot Lake microbial mat communities. The seasonal development and organization of these structured microbial mats provide opportunities for analysis of the temporal and physical dynamics that feed back to community function.

  19. Regulation of electron transfer processes affects phototrophic mat structure and activity

    Directory of Open Access Journals (Sweden)

    Haluk eBeyenal

    2015-09-01

    Full Text Available Phototrophic microbial mats are among the most diverse ecosystems in nature. These systems undergo daily cycles in redox potential caused by variations in light energy input and metabolic interactions among the microbial species. In this work, solid electrodes with controlled potentials were placed under mats to study the electron transfer processes between the electrode and the microbial mat. The phototrophic microbial mat was harvested from Hot Lake, a hypersaline, epsomitic lake located near Oroville (Washington, USA. We operated two reactors: graphite electrodes were polarized at potentials of -700 mVAg/AgCl (cathodic mat system and +300 mVAg/AgCl (anodic mat system and the electron transfer rates between the electrode and mat were monitored. We observed a diel cycle of electron transfer rates for both anodic and cathodic mat systems. Interestingly, the cathodic mats generated the highest reducing current at the same time points that the anodic mats showed the highest oxidizing current. To characterize the physicochemical factors influencing electron transfer processes, we measured depth profiles of dissolved oxygen and sulfide in the mats using microelectrodes. We further demonstrated that the mat-to-electrode and electrode-to-mat electron transfer rates were light- and temperature-dependent. Using nuclear magnetic resonance (NMR imaging, we determined that the electrode potential regulated the diffusivity and porosity of the microbial mats. Both porosity and diffusivity were higher in the cathodic mats than in the anodic mats. We also used NMR spectroscopy for high-resolution quantitative metabolite analysis and found that the cathodic mats had significantly higher concentrations of osmoprotectants such as betaine and trehalose. Subsequently, we performed amplicon sequencing across the V4 region of the 16S rRNA gene of incubated mats to understand the impact of electrode potential on microbial community structure. These data suggested that

  20. Arsenite as an electron donor for anoxygenic photosynthesis: Description of three strains of Ectothiorhodospria from Mono Lake, California, and Big Soda Lake, Nevada

    Science.gov (United States)

    McCann, Shelley; Boren, Alison; Hernandez-Maldonado, Jaime; Stoneburner, Brendon; Saltikov, Chad W; Stolz, John F.; Oremland, Ronald S.

    2017-01-01

    Three novel strains of photosynthetic bacteria from the family Ectothiorhodospiraceae were isolated from soda lakes of the Great Basin Desert, USA by employing arsenite (As(III)) as the sole electron donor in the enrichment/isolation process. Strain PHS-1 was previously isolated from a hot spring in Mono Lake, while strain MLW-1 was obtained from Mono Lake sediment, and strain BSL-9 was isolated from Big Soda Lake. Strains PHS-1, MLW-1, and BSL-9 were all capable of As(III)-dependent growth via anoxygenic photosynthesis and contained homologs of arxA, but displayed different phenotypes. Comparisons were made with three related species: Ectothiorhodospira shaposhnikovii DSM 2111, Ectothiorhodospira shaposhnikovii DSM 243T, and Halorhodospira halophila DSM 244. All three type cultures oxidized arsenite to arsenate but did not grow with As(III) as the sole electron donor. DNA–DNA hybridization indicated that strain PHS-1 belongs to the same species as Ect. shaposhnikovii DSM 2111 (81.1% sequence similarity), distinct from Ect. shaposhnikovii DSM 243T (58.1% sequence similarity). These results suggest that the capacity for light-driven As(III) oxidation is a common phenomenon among purple photosynthetic bacteria in soda lakes. However, the use of As(III) as a sole electron donor to sustain growth via anoxygenic photosynthesis is confined to novel isolates that were screened for by this selective cultivation criterion.

  1. Brain plasticity and aerobic fitness

    OpenAIRE

    2014-01-01

    Regular aerobic exercise has a wide range of positive effects on health and cognition. Exercise has been demonstrated to provide a particularly powerful and replicable method of triggering a wide range of structural changes within both human and animal brains. However, the details and mechanisms of these changes remain poorly understood. This thesis undertakes a comprehensive examination of the relationship between brain plasticity and aerobic exercise. A large, longitudinal experiment ...

  2. Photosynthetic Versatility in the Genome of Geitlerinema sp. PCC 9228 (Formerly Oscillatoria limnetica ‘Solar Lake’), a Model Anoxygenic Photosynthetic Cyanobacterium

    Science.gov (United States)

    Grim, Sharon L.; Dick, Gregory J.

    2016-01-01

    Anoxygenic cyanobacteria that use sulfide as the electron donor for photosynthesis are a potentially influential but poorly constrained force on Earth’s biogeochemistry. Their versatile metabolism may have boosted primary production and nitrogen cycling in euxinic coastal margins in the Proterozoic. In addition, they represent a biological mechanism for limiting the accumulation of atmospheric oxygen, especially before the Great Oxidation Event and in the low-oxygen conditions of the Proterozoic. In this study, we describe the draft genome sequence of Geitlerinema sp. PCC 9228, formerly Oscillatoria limnetica ‘Solar Lake’, a mat-forming diazotrophic cyanobacterium that can switch between oxygenic photosynthesis and sulfide-based anoxygenic photosynthesis (AP). Geitlerinema possesses three variants of psbA, which encodes protein D1, a core component of the photosystem II reaction center. Phylogenetic analyses indicate that one variant is closely affiliated with cyanobacterial psbA genes that code for a D1 protein used for oxygen-sensitive processes. Another version is phylogenetically similar to cyanobacterial psbA genes that encode D1 proteins used under microaerobic conditions, and the third variant may be cued to high light and/or elevated oxygen concentrations. Geitlerinema has the canonical gene for sulfide quinone reductase (SQR) used in cyanobacterial AP and a putative transcriptional regulatory gene in the same operon. Another operon with a second, distinct sqr and regulatory gene is present, and is phylogenetically related to sqr genes used for high sulfide concentrations. The genome has a comprehensive nif gene suite for nitrogen fixation, supporting previous observations of nitrogenase activity. Geitlerinema possesses a bidirectional hydrogenase rather than the uptake hydrogenase typically used by cyanobacteria in diazotrophy. Overall, the genome sequence of Geitlerinema sp. PCC 9228 highlights potential cyanobacterial strategies to cope with

  3. Cenoses of phototrophic algae of ultrasaline lakes in the Kulunda steppe (Altai krai, Russian Federation)

    Science.gov (United States)

    Sapozhnikov, Ph. V.; Kalinina, O. Yu.; Nikitin, M. A.; Samylina, O. S.

    2016-01-01

    In 2012, expeditions of the Institute of Microbiology, Russian Academy of Sciences, delivered samples of algo-bacterial mats from Kulunda steppe alkaline lakes (Petukhovskoe alkaline lake, Tanatar VI, and Gorchina III). The filamentous alga Ctenocladus circinnatus (Chlorophyta) acted as an edificator of the mats. The composition of cenoses algocomponents also included chlorophytes Dunaliella viridis and Picocystis salinarum as well as diatoms Anomeoneis sphaerophora, Brachysira brebissonii, B. zellensis, Mastogloia pusilla var. subcapitata, Nitzschia amphibia, N. cf. communis, and Nitzschia sp. 1. The composition and structure of phototrophic algae cenoses (including diatom taxocenes) were described for the investigated lakes for the first time. For the period from 2011 to 2012, the total mineralization significantly increased in lakes. This involved sensible alterations of cenoses. B. zellensis was the most permanent component of diatom taxocenes in both seasons. In the summer of 2011, it was often accompanied by A. sphaerophora and B. brebissonii. In the summer of 2012, A. sphaerophora was found only singularly in Lake Gorchina III, and some biotopes of Lake Tanatar VI were massively inhabited by N. cf. communis, including colonies that had not been previously described for the species. The genetic analysis of three diatoms, which are markedly different from each other in their appearance and were sampled from different lakes but were all determined as Nitzschia cf. communis, showed their complete similarity to each other with the 18S rRNA gene fragment and the highest similarity of all the three diatoms with the species Nitzschia communis.

  4. Photorespiration and Rate Synchronization in a Phototroph-Heterotroph Microbial Consortium

    Directory of Open Access Journals (Sweden)

    Fadoua El Moustaid

    2017-03-01

    Full Text Available Theprocessofoxygenicphotosynthesisisrobustandubiquitous,relyingcentrallyoninput of light, carbon dioxide, and water, which in many environments are all abundantly available, and from which are produced, principally, oxygen and reduced organic carbon. However, photosynthetic machinery can be conflicted by the simultaneous presence of carbon dioxide and oxygen through a process sometimes called photorespiration. We present here a model of phototrophy, including competition for RuBisCO binding sites between oxygen and carbon dioxide, in a chemostat-based microbial population. The model connects to the idea of metabolic pathways to track carbon and degree of reduction through the system. We find decomposition of kinetics into elementary flux modes a mathematically natural way to study synchronization of mismatched rates of photon input and chemostat turnover. In the single species case, though total biomass is reduced by photorespiration, protection from excess light exposures and its consequences (oxidative and redox stress may result. We also find the possibility that a consortium of phototrophs with heterotrophs can recycle photorespiration byproduct into increased biomass at the cost of increase in oxidative product (here, oxygen.

  5. Hydrologic variability affects invertebrate grazing on phototrophic biofilms in stream microcosms.

    Directory of Open Access Journals (Sweden)

    Serena Ceola

    Full Text Available The temporal variability of streamflow is known to be a key feature structuring and controlling fluvial ecological communities and ecosystem processes. Although alterations of streamflow regime due to habitat fragmentation or other anthropogenic factors are ubiquitous, a quantitative understanding of their implications on ecosystem structure and function is far from complete. Here, by experimenting with two contrasting flow regimes in stream microcosms, we provide a novel mechanistic explanation for how fluctuating flow regimes may affect grazing of phototrophic biofilms (i.e., periphyton by an invertebrate species (Ecdyonurus sp.. In both flow regimes light availability was manipulated as a control on autotroph biofilm productivity and grazer activity, thereby allowing the test of flow regime effects across various ratios of biofilm biomass to grazing activity. Average grazing rates were significantly enhanced under variable flow conditions and this effect was highest at intermediate light availability. Our results suggest that stochastic flow regimes, characterised by suitable fluctuations and temporal persistence, may offer increased windows of opportunity for grazing under favourable shear stress conditions. This bears important implications for the development of comprehensive schemes for water resources management and for the understanding of trophic carbon transfer in stream food webs.

  6. Development of Synechocystis sp. PCC 6803 as a Phototrophic Cell Factory

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    Fuzhong Zhang

    2013-08-01

    Full Text Available Cyanobacteria (blue-green algae play profound roles in ecology and biogeochemistry. One model cyanobacterial species is the unicellular cyanobacterium Synechocystis sp. PCC 6803. This species is highly amenable to genetic modification. Its genome has been sequenced and many systems biology and molecular biology tools are available to study this bacterium. Recently, researchers have put significant efforts into understanding and engineering this bacterium to produce chemicals and biofuels from sunlight and CO2. To demonstrate our perspective on the application of this cyanobacterium as a photosynthesis-based chassis, we summarize the recent research on Synechocystis 6803 by focusing on five topics: rate-limiting factors for cell cultivation; molecular tools for genetic modifications; high-throughput system biology for genome wide analysis; metabolic modeling for physiological prediction and rational metabolic engineering; and applications in producing diverse chemicals. We also discuss the particular challenges for systems analysis and engineering applications of this microorganism, including precise characterization of versatile cell metabolism, improvement of product rates and titers, bioprocess scale-up, and product recovery. Although much progress has been achieved in the development of Synechocystis 6803 as a phototrophic cell factory, the biotechnology for “Compounds from Synechocystis” is still significantly lagging behind those for heterotrophic microbes (e.g., Escherichia coli.

  7. Rhodobacter changlensis sp. nov., a psychrotolerant, phototrophic alphaproteobacterium from the Himalayas of India.

    Science.gov (United States)

    Anil Kumar, P; Srinivas, T N R; Sasikala, Ch; Ramana, Ch V

    2007-11-01

    A Gram-negative, non-motile, oval to rod-shaped, psychrotolerant, phototrophic, purple non-sulfur bacterium (designated strain JA139T) was isolated from a snow sample from Changla Pass in the Indian Himalayas. Strain JA139T had vesicular-type intracytoplasmic membrane structures and contained bacteriochlorophyll a and most probably spheroidene-like carotenoids. Biotin, niacin and thiamine were required for growth of strain JA139T. Phylogenetic analysis on the basis of 16S rRNA gene sequences showed that the strain clustered with species of the genus Rhodobacter but was distinctly separate from all recognized members of the family Rhodobacteraceae. Based on the genotypic and phenotypic differences observed between strain JA139T and recognized Rhodobacter species, strain JA139T is considered to represent a novel species of the genus, for which the name Rhodobacter changlensis sp. nov. is proposed. The type strain is JA139T (=DSM 18774T=CCUG 53722T=JCM 14338T).

  8. Comparative evaluation of phototrophic microtiter plate cultivation against laboratory-scale photobioreactors.

    Science.gov (United States)

    Morschett, Holger; Schiprowski, Danny; Rohde, Jannis; Wiechert, Wolfgang; Oldiges, Marco

    2017-01-18

    Extended cultivation times, rendering phototrophic bioprocess development time inefficient, resulted in the recent development of micro-photobioreactors enabling accelerated process development. However, especially for laboratory photobioreactors, only little is known concerning the influence of design on process performance. Thus, the aim of the present investigation was to evaluate the scalability of a microtiter plate-based parallelized micro-photobioreactor against a representative set of established laboratory photobioreactors. Lipid production by Chlorella vulgaris was used as a model system. During exponential growth, the microtiter plate cultures achieved maximal growth rates of ca. 1.44 ± 0.02 day(-1) being in good agreement with the larger systems. Moreover, cultures in the micro-photobioreactor could be kept in the exponential phase up to the highest biomass concentrations most probably due to the beneficial light supply at this scale. Compared to the shake flask and test tube cultures, microtiter plate cultivation achieved an equivalent biomass yield, lipid content, and lipid fingerprint. In contrast, the flat-panel process resulted only in marginal productivity due to insufficient light supply. Thus, microtiter plates showed good scalability to the investigated laboratory photobioreactors as overall differences were rather small taking the differing scales into account.

  9. Phototrophic periphyton techniques combine phosphorous removal and recovery for sustainable salt-soil zone.

    Science.gov (United States)

    Lu, Haiying; Feng, Yanfang; Wu, Yonghong; Yang, Linzhang; Shao, Hongbo

    2016-10-15

    The P (Pi as KH2PO4 and Po as ATP) removal processes by phototrophic periphyton were investigated by determining the removal kinetics, metal content (Ca, Mg, Al, Fe, Cu, and Zn) of the solution and P fractions (Labile-P, Fe/Al-P, Ca-P, and Res-P) within the periphyton. Results showed that the periphyton was able to remove completely both Pi and Po after 48h when periphyton content was greater than 0.2gL(-1) (dry weight). The difference between Pi and Po removal was the conversion of Po into Pi by the periphyton, after that the removal mechanism was similar. The P removal mechanism was mainly due to the adsorption on the surfaces of the periphyton, including two aspects: i) the adsorption of PO4(3-) onto metal salts such as calcium carbonate (~50%) and ii) complexation between PO4(3-) and metal cations such as Ca(2+) (~40%). However, this bio-adsorptional process was significantly influenced by the extracellular polymeric substance (EPS) of periphyton, water hardness, initial P concentration, temperature and light intensity. This study not only deepens the understanding of P biogeochemical process in aquatic ecosystem, but provides a potential biomaterial for combining phosphorous removal and recovery from non-point source wastewaters, especially around salt-soil zone.

  10. Degradation of p-nitrophenol by the phototrophic bacterium Rhodobacter capsulatus.

    Science.gov (United States)

    Roldán, M D; Blasco, R; Caballero, F J; Castillo, F

    1998-01-01

    The phototrophic bacterium Rhodobacter capsulatus detoxified p-nitrophenol and 4-nitrocatechol. The bacterium tolerated moderate concentrations of p-nitrophenol (up to 0.5 mM) and degraded it under light at an optimal O2 pressure of 20 kPa. The bacterium did not metabolize the xenobiotic in the dark or under strictly anoxic conditions or high O2 pressure. Bacterial growth with acetate in the presence of p-nitrophenol took place with the simultaneous release of nonstoichiometric amounts of 4-nitrocatechol, which can also be degraded by the bacterium. Crude extracts from R. capsulatus produced 4-nitrocatechol from p-nitrophenol upon the addition of NAD(P)H, although at a very low rate. A constitutive catechol 1, 2-dioxygenase activity yielding cis,cis-muconate was also detected in crude extracts of R. capsulatus. Further degradation of 4-nitrocatechol included both nitrite- and CO2-releasing steps since: (1) a strain of R. capsulatus (B10) unable to assimilate nitrate and nitrite released nitrite into the medium when grown with p-nitrophenol or 4-nitrocatechol, and the nitrite concentration was stoichiometric with the 4-nitrocatechol degraded, and (2) cultures of R. capsulatus growing microaerobically produced low amounts of 14CO2 from radiolabeled p-nitrophenol. The radioactivity was also incorporated into cellular compounds from cells grown with uniformly labeled 14C-p-nitrophenol. From these results we concluded that the xenobiotic is used as a carbon source by R. capsulatus, but that only the strain able to assimilate nitrite (E1F1) can use p-nitrophenol as a nitrogen source.

  11. Melatonin in plants and other phototrophs: advances and gaps concerning the diversity of functions.

    Science.gov (United States)

    Hardeland, Rüdiger

    2015-02-01

    Melatonin is synthesized in Alphaproteobacteria, Cyanobacteria, Dinoflagellata, Euglenoidea, Rhodophyta, Phae ophyta, and Viridiplantae. The biosynthetic pathways have been identified in dinoflagellates and plants. Other than in dinoflagellates and animals, tryptophan is not 5-hydroxylated in plants but is first decarboxylated. Serotonin is formed by 5-hydroxylation of tryptamine. Serotonin N-acetyltransferase is localized in plastids and lacks homology to the vertebrate aralkylamine N-acetyltransferase. Melatonin content varies considerably among species, from a few picograms to several micrograms per gram, a strong hint for different actions of this indoleamine. At elevated levels, the common and presumably ancient property as an antioxidant may prevail. Although melatonin exhibits nocturnal maxima in some phototrophs, it is not generally a mediator of the signal 'darkness'. In various plants, its formation is upregulated by visible and/or UV light. Increases are often induced by high or low temperature and several other stressors including drought, salinity, and chemical toxins. In Arabidopsis, melatonin induces cold- and stress-responsive genes. It has been shown to support cold resistance and to delay experimental leaf senescence. Transcriptome data from Arabidopsis indicate upregulation of genes related to ethylene, abscisic acid, jasmonic acid, and salicylic acid. Auxin-like actions have been reported concerning root growth and inhibition, and hypocotyl or coleoptile lengthening, but effects caused by melatonin and auxins can be dissected. Assumptions on roles in flower morphogenesis and fruit ripening are based mainly on concentration changes. Whether or not melatonin will find a place in the phytohormone network depends especially on the identification of molecular signals regulating its synthesis, high-affinity binding sites, and signal transduction pathways.

  12. Aerobic microbial enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Torsvik, T. [Univ. of Bergen (Norway); Gilje, E.; Sunde, E.

    1995-12-31

    In aerobic MEOR, the ability of oil-degrading bacteria to mobilize oil is used to increase oil recovery. In this process, oxygen and mineral nutrients are injected into the oil reservoir in order to stimulate growth of aerobic oil-degrading bacteria in the reservoir. Experiments carried out in a model sandstone with stock tank oil and bacteria isolated from offshore wells showed that residual oil saturation was lowered from 27% to 3%. The process was time dependent, not pore volume dependent. During MEOR flooding, the relative permeability of water was lowered. Oxygen and active bacteria were needed for the process to take place. Maximum efficiency was reached at low oxygen concentrations, approximately 1 mg O{sub 2}/liter.

  13. Analysis of a marine phototrophic biofilm by confocal laser scanning microscopy using the new image quantification software PHLIP

    Directory of Open Access Journals (Sweden)

    Almeida Jonas S

    2006-01-01

    Full Text Available Abstract Background Confocal laser scanning microscopy (CLSM is the method of choice to study interfacial biofilms and acquires time-resolved three-dimensional data of the biofilm structure. CLSM can be used in a multi-channel modus where the different channels map individual biofilm components. This communication presents a novel image quantification tool, PHLIP, for the quantitative analysis of large amounts of multichannel CLSM data in an automated way. PHLIP can be freely downloaded from http://phlip.sourceforge.net. Results PHLIP is an open source public license Matlab toolbox that includes functions for CLSM imaging data handling and ten image analysis operations describing various aspects of biofilm morphology. The use of PHLIP is here demonstrated by a study of the development of a natural marine phototrophic biofilm. It is shown how the examination of the individual biofilm components using the multi-channel capability of PHLIP allowed the description of the dynamic spatial and temporal separation of diatoms, bacteria and organic and inorganic matter during the shift from a bacteria-dominated to a diatom-dominated phototrophic biofilm. Reflection images and weight measurements complementing the PHLIP analyses suggest that a large part of the biofilm mass consisted of inorganic mineral material. Conclusion The presented case study reveals new insight into the temporal development of a phototrophic biofilm where multi-channel imaging allowed to parallel monitor the dynamics of the individual biofilm components over time. This application of PHLIP presents the power of biofilm image analysis by multi-channel CLSM software and demonstrates the importance of PHLIP for the scientific community as a flexible and extendable image analysis platform for automated image processing.

  14. Mineral and non-carbon nutrient utilization and recovery during sequential phototrophic-heterotrophic growth of lipid-rich algae.

    Science.gov (United States)

    Bohutskyi, Pavlo; Liu, Kexin; Kessler, Ben A; Kula, Thomas; Hong, Yongseok; Bouwer, Edward J; Betenbaugh, Michael J; Allnutt, F C Thomas

    2014-06-01

    A critical factor in implementing microalgal biofuels for mass production is the nutrient requirements. The current study investigated the fate of macro- and micronutrients and their availability in a sequential phototrophic-heterotrophic production process for the lipid rich microalga Auxenochlorella protothecoides. More than 99 % (by weight) of overall process nutrients were supplied during the initial photoautotrophic stage reflecting its significantly larger volume. Under photoautotrophic growth conditions only 9-35 % of supplied Mn, S, Fe, N, Mg, and Cu and less than 5 % of P, Mo, Co, B, Zn, and Ca were consumed by the algae. The rest of these nutrients remain in the spent growth media during the culture concentration-down from an 800 L phototrophic pond to a 5 L heterotrophic fermenter. In contrast, Zn, Mo, Mn, Mg, Ca, and N were exhausted (90-99 % removal) during the first 25 h of the heterotrophic growth stage. The depletion of these key nutrients may have ultimately limited the final biomass density and/or lipid productivity achieved. Approximately 10-20 % of the total supplied S, Mn, Fe, N, and Cu and 5 % of Ca and Zn were assimilated into algal biomass. Several elements including N, P, Mn, B, Cu, Ca, Mg, S, and Fe were released back into the liquid phase by anaerobic digestion (AD) of the residual biomass after lipid extraction. The nutrients recovered from the AD effluent and remaining in the spent medium should be recycled or their initial concentration to the phototrophic stage decreased to enhance process economics and sustainability for future commercialization of algal-derived biofuels.

  15. Aerobic conditioning for team sport athletes.

    Science.gov (United States)

    Stone, Nicholas M; Kilding, Andrew E

    2009-01-01

    Team sport athletes require a high level of aerobic fitness in order to generate and maintain power output during repeated high-intensity efforts and to recover. Research to date suggests that these components can be increased by regularly performing aerobic conditioning. Traditional aerobic conditioning, with minimal changes of direction and no skill component, has been demonstrated to effectively increase aerobic function within a 4- to 10-week period in team sport players. More importantly, traditional aerobic conditioning methods have been shown to increase team sport performance substantially. Many team sports require the upkeep of both aerobic fitness and sport-specific skills during a lengthy competitive season. Classic team sport trainings have been shown to evoke marginal increases/decreases in aerobic fitness. In recent years, aerobic conditioning methods have been designed to allow adequate intensities to be achieved to induce improvements in aerobic fitness whilst incorporating movement-specific and skill-specific tasks, e.g. small-sided games and dribbling circuits. Such 'sport-specific' conditioning methods have been demonstrated to promote increases in aerobic fitness, though careful consideration of player skill levels, current fitness, player numbers, field dimensions, game rules and availability of player encouragement is required. Whilst different conditioning methods appear equivalent in their ability to improve fitness, whether sport-specific conditioning is superior to other methods at improving actual game performance statistics requires further research.

  16. Development of a Laboratory Model of a Phototroph-Heterotroph Mixed-Species Biofilm at the Stone/Air Interface.

    Science.gov (United States)

    Villa, Federica; Pitts, Betsey; Lauchnor, Ellen; Cappitelli, Francesca; Stewart, Philip S

    2015-01-01

    Recent scientific investigations have shed light on the ecological importance and physiological complexity of subaerial biofilms (SABs) inhabiting lithic surfaces. In the field of sustainable cultural heritage (CH) preservation, mechanistic approaches aimed at investigation of the spatiotemporal patterns of interactions between the biofilm, the stone, and the atmosphere are of outstanding importance. However, these interactions have proven difficult to explore with field experiments due to the inaccessibility of samples, the complexity of the ecosystem under investigation and the temporal resolution of the experiments. To overcome these limitations, we aimed at developing a unifying methodology to reproduce a fast-growing, phototroph-heterotroph mixed species biofilm at the stone/air interface. Our experiments underscore the ability of the dual-species SAB model to capture functional traits characteristic of biofilms inhabiting lithic substrate such as: (i) microcolonies of aggregated bacteria; (ii) network like structure following surface topography; (iii) cooperation between phototrophs and heterotrophs and cross feeding processes; (iv) ability to change the chemical parameters that characterize the microhabitats; (v) survival under desiccation and (vi) biocide tolerance. With its advantages in control, replication, range of different experimental scenarios and matches with the real ecosystem, the developed model system is a powerful tool to advance our mechanistic understanding of the stone-biofilm-atmosphere interplay in different environments.

  17. Development of a laboratory model of a phototroph-heterotroph mixed-species biofilm at the stone/air interface

    Directory of Open Access Journals (Sweden)

    Federica eVilla

    2015-11-01

    Full Text Available Recent scientific investigations have shed light on the ecological importance and physiological complexity of subaerial biofilms (SABs inhabiting lithic surfaces. In the field of sustainable cultural heritage (CH preservation, mechanistic approaches aimed at investigation of the spatiotemporal patterns of interactions between the biofilm, the stone, and the atmosphere are of outstanding importance. However, these interactions have proven difficult to explore with field experiments due to the inaccessibility of samples, the complexity of the ecosystem under investigation and the temporal resolution of the experiments.To overcome these limitations, we aimed at developing a unifying methodology to reproduce a fast-growing, phototroph-heterotroph mixed species biofilm at the stone/air interface. Our experiments underscore the ability of the dual-species SAB model to capture functional traits characteristic of biofilms inhabiting lithic substrate such as: i microcolonies of aggregated bacteria; ii network like structure following surface topography; iii cooperation between phototrophs and heterotrophs and cross feeding processes; iv ability to change the chemical parameters that characterize the microhabitats; v survival under desiccation and vi biocide tolerance. With its advantages in control, replication, range of different experimental scenarios and matches with the real ecosystem, the developed model system is a powerful tool to advance our mechanistic understanding of the stone-biofilm-atmosphere interplay in different environments.

  18. Phototrophic Biofilm Assembly in Microbial-Mat-Derived Unicyanobacterial Consortia: Model Systems for the Study of Autotroph-Heterotroph Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Jessica K.; Hutchison, Janine R.; Renslow, Ryan S.; Kim, Young-Mo; Chrisler, William B.; Engelmann, Heather E.; Dohnalkova, Alice; Hu, Dehong; Metz, Thomas O.; Fredrickson, Jim K.; Lindemann, Stephen R.

    2014-04-07

    Though microbial autotroph-heterotroph interactions influence biogeochemical cycles on a global scale, the diversity and complexity of natural systems and their intractability to in situ environmental manipulation makes elucidation of the principles governing these interactions challenging. Examination of primary succession during phototrophic biofilm assembly provides a robust means by which to elucidate the dynamics of such interactions and determine their influence upon recruitment and maintenance of phylogenetic and functional diversity in microbial communities. We isolated and characterized two unicyanobacterial consortia from the Hot Lake phototrophic mat, quantifying the structural and community composition of their assembling biofilms. The same heterotrophs were retained in both consortia and included members of Alphaproteobacteria, Gammaproteobacteria, and Bacteroidetes, taxa frequently reported as consorts of microbial photoautotrophs. Cyanobacteria led biofilm assembly, eventually giving way to a late heterotrophic bloom. The consortial biofilms exhibited similar patterns of assembly, with the relative abundances of members of Bacteroidetes and Alphaproteobacteria increasing and members of Gammaproteobacteria decreasing as colonization progressed. Despite similar trends in assembly at higher taxa, the consortia exhibited substantial differences in community structure at the species level. These similar patterns of assembly with divergent community structures suggest that, while similar niches are created by the metabolism of the cyanobacteria, the resultant webs of autotroph-heterotroph and heterotroph-heterotroph interactions driving metabolic exchange are specific to each primary producer. Altogether, our data support these Hot Lake unicyanobacterial consortia as generalizable model systems whose simplicity and tractability permit the deciphering of community assembly principles relevant to natural microbial communities.

  19. Exposure of phototrophs to 548 days in low Earth orbit: microbial selection pressures in outer space and on early earth.

    Science.gov (United States)

    Cockell, Charles S; Rettberg, Petra; Rabbow, Elke; Olsson-Francis, Karen

    2011-10-01

    An epilithic microbial community was launched into low Earth orbit, and exposed to conditions in outer space for 548 days on the European Space Agency EXPOSE-E facility outside the International Space Station. The natural phototroph biofilm was augmented with akinetes of Anabaena cylindrica and vegetative cells of Nostoc commune and Chroococcidiopsis. In space-exposed dark controls, two algae (Chlorella and Rosenvingiella spp.), a cyanobacterium (Gloeocapsa sp.) and two bacteria associated with the natural community survived. Of the augmented organisms, cells of A. cylindrica and Chroococcidiopsis survived, but no cells of N. commune. Only cells of Chroococcidiopsis were cultured from samples exposed to the unattenuated extraterrestrial ultraviolet (UV) spectrum (>110 nm or 200 nm). Raman spectroscopy and bright-field microscopy showed that under these conditions the surface cells were bleached and their carotenoids were destroyed, although cell morphology was preserved. These experiments demonstrate that outer space can act as a selection pressure on the composition of microbial communities. The results obtained from samples exposed to >200 nm UV (simulating the putative worst-case UV exposure on the early Earth) demonstrate the potential for epilithic colonization of land masses during that time, but that UV radiation on anoxic planets can act as a strong selection pressure on surface-dwelling organisms. Finally, these experiments have yielded new phototrophic organisms of potential use in biomass and oxygen production in space exploration.

  20. Lower limb loading in step aerobic dance.

    Science.gov (United States)

    Wu, H-W; Hsieh, H-M; Chang, Y-W; Wang, L-H

    2012-11-01

    Participation in aerobic dance is associated with a number of lower extremity injuries, and abnormal joint loading seems to be a factor in these. However, information on joint loading is limited. The purpose of this study was to investigate the kinetics of the lower extremity in step aerobic dance and to compare the differences of high-impact and low-impact step aerobic dance in 4 aerobic movements (mambo, kick, L step and leg curl). 18 subjects were recruited for this study. High-impact aerobic dance requires a significantly greater range of motion, joint force and joint moment than low-impact step aerobic dance. The peak joint forces and moments in high-impact step aerobic dance were found to be 1.4 times higher than in low-impact step aerobic dance. Understanding the nature of joint loading may help choreographers develop dance combinations that are less injury-prone. Furthermore, increased knowledge about joint loading may be helpful in lowering the risk of injuries in aerobic dance instructors and students.

  1. Energetic and metabolic consequences of aerobic and an-aerobic ATP-production.

    NARCIS (Netherlands)

    Schreurs, V.V.A.M.; Aarts, M.J.; IJssennagger, N.; Hermans, J.; Hendriks, W.H.

    2007-01-01

    ATP, the currency of cellular energy metabolism, can be produced during aerobic and an-aerobic oxidation of metabolic substrates. The aerobic oxidation yields CO2 + H2O as metabolic end products while ATP is produced by oxidative phosphorylation in the mitochondria. Carbohydrate, protein and fat pro

  2. Aerobic respiration in the Archaean?

    Science.gov (United States)

    Towe, K M

    1990-11-01

    The Earth's atmosphere during the Archaean era (3,800-2,500 Myr ago) is generally thought to have been anoxic, with the partial pressure of atmospheric oxygen about 10(-12) times the present value. In the absence of aerobic consumption of oxygen produced by photosynthesis in the ocean, the major sink for this oxygen would have been oxidation of dissolved Fe(II). Atmospheric oxygen would also be removed by the oxidation of biogenic methane. But even very low estimates of global primary productivity, obtained from the amounts of organic carbon preserved in Archaean rocks, seem to require the sedimentation of an unrealistically large amount of iron and the oxidation of too much methane if global anoxia was to be maintained. I therefore suggest that aerobic respiration must have developed early in the Archaean to prevent a build-up of atmospheric oxygen before the Proterozoic. An atmosphere that contained a low (0.2-0.4%) but stable proportion of oxygen is required.

  3. CO2 assimilation in the chemocline of Lake Cadagno is dominated by a few types of phototrophic purple sulfur bacteria

    DEFF Research Database (Denmark)

    Storelli, Nicola; Peduzzi, Sandro; Saad, Maged;

    2013-01-01

    Lake Cadagno is characterized by a compact chemocline that harbors high concentrations of various phototrophic sulfur bacteria. Four strains representing the numerically most abundant populations in the chemocline were tested in dialysis bags in situ for their ability to fix CO₂. The purple sulfu...

  4. Aerobic rice mechanization: techniques for crop establishment

    Science.gov (United States)

    Khusairy, K. M.; Ayob, H.; Chan, C. S.; Fauzi, M. I. Mohamed; Mohamad Fakhrul, Z. O.; Shahril Shah, G. S. M.; Azlan, O.; Rasad, M. A.; Hashim, A. M.; Arshad, Z.; E, E. Ibrahim; Saifulizan, M. N.

    2015-12-01

    Rice being the staple food crops, hundreds of land races in it makes the diversity of rice crops. Aerobic rice production was introduced which requires much less water input to safeguard and sustain the rice production and conserve water due to decreasing water resources, climatic changes and competition from urban and industrial users. Mechanization system plays an important role for the success of aerobic rice cultivation. All farming activities for aerobic rice production are run on aerobic soil conditions. Row seeder mechanization system is developed to replace conventional seeding technique on the aerobic rice field. It is targeted for small and the large scale aerobic rice farmers. The aero - seeder machine is used for the small scale aerobic rice field, while the accord - seeder is used for the large scale aerobic rice field. The use of this mechanization machine can eliminate the tedious and inaccurate seeding operations reduce labour costs and increases work rate. The machine is easy to operate and it can increase crop establishment rate. It reduce missing hill, increasing planting and crop with high yield can be produce. This machine is designed for low costs maintenance and it is easy to dismantle and assemble during maintenance and it is safe to be used.

  5. Quinones in aerobic and anaerobic mitochondria

    NARCIS (Netherlands)

    van der Klei, S.A.

    2009-01-01

    Ubiquinone (UQ), also known as coenzyme Q, is a ubiquitous quinone and is known to have several functions. One of these functions is electron carrier in the mitochondrial electron transport chain of aerobically functioning bacteria and eukaryotes. In contrast to this aerobically functioning quinone,

  6. Effect of copper and lead on two consortia of phototrophic microorganisms and their capacity to sequester metals

    Energy Technology Data Exchange (ETDEWEB)

    Burgos, A. [Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Edifici C, Campus de UAB, Bellaterra (Cerdanyola del Vallès), 08193 Barcelona (Spain); Departamento de Recursos Hidrobiológicos, Universidad de Nariño, Pasto (N) (Colombia); Maldonado, J. [Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Edifici C, Campus de UAB, Bellaterra (Cerdanyola del Vallès), 08193 Barcelona (Spain); De los Rios, A. [Museo Nacional de Ciencias Naturales(CSIC), Serrano 115 dpdo, 28006 Madrid (Spain); Solé, A. [Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Edifici C, Campus de UAB, Bellaterra (Cerdanyola del Vallès), 08193 Barcelona (Spain); Esteve, I., E-mail: isabel.esteve@uab.cat [Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Edifici C, Campus de UAB, Bellaterra (Cerdanyola del Vallès), 08193 Barcelona (Spain); Departamento de Recursos Hidrobiológicos, Universidad de Nariño, Pasto (N) (Colombia); Museo Nacional de Ciencias Naturales(CSIC), Serrano 115 dpdo, 28006 Madrid (Spain)

    2013-09-15

    Highlights: •We studied the tolerance-resistance of phototrophic microorganisms to copper and lead. •We determined the capacity of consortia of microorganisms to sequester copper and lead. •CLSM-λscan is a technique for evaluating in vivo effect of metals on microorganisms. •SEM-EDX and TEM-EDX determined the capacity of microorganisms to sequester metals. -- Abstract: The roles of consortia of phototrophic microorganisms have been investigated in this paper to determine their potential role to tolerate or resist metals and to capture them from polluted cultures. With this purpose, two consortia of microorganisms: on one hand, Geitlerinema sp. DE2011 (Ge) and Scenedesmus sp. DE2009 (Sc) (both identified in this paper by molecular biology methods) isolated from Ebro Delta microbial mats, and on the other, Spirulina sp. PCC 6313 (Sp) and Chroococcus sp. PCC 9106 (Ch), from Pasteur culture collection were polluted with copper and lead. In order to analyze the ability of these consortia to tolerate and capture metals, copper and lead were selected, because both have been detected in Ebro Delta microbial mats. The tolerance-resistance to copper and lead for both consortia was determined in vivo and at cellular level by Confocal Laser Scanning Microscopy (CLSM-λscan function). The results obtained demonstrate that both consortia are highly tolerant-resistant to lead and that the limits between the copper concentration having cytotoxic effect and that having an essential effect are very close in these microorganisms. The capacity of both consortia to capture extra- and intracellular copper and lead was determined by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) respectively, coupled to an Energy Dispersive X-ray detector (EDX). The results showed that all the microorganisms assayed were able to capture copper extracellularly in the extrapolymeric substances, and lead extra- and intracellularly in polyphosphate inclusions. Moreover

  7. Experimental modelling of Calcium carbonate precipitation in the presence of phototrophic anaerobic bacteria Rhodovulum sp.

    Science.gov (United States)

    Bundeleva, Irina; Shirokova, Liudmila; Benezeth, Pascale; Pokrovsky, Oleg; Kompantseva, Elena

    2010-05-01

    Carbonate biomineralization is considered as one of the main natural processes controlling CO2 levels in the atmosphere both in the past and at present time. Haloalcaliphilic Rhodovulum sp. A-20s isolated from soda lake in southern Siberia and halophilic neutrophilic Rhodovulum sp. S-1765 isolated from hypersaline water body in Crimea steppe represent a large group of phototrophic bacteria likely to be involved in CaCO3 formation in soda and saline lakes. These bacteria use organic substrates for non-oxygenic photosynthesis and thus may mediate CaCO3 precipitation without CO2 consumption in highly-saline, highly-alkaline, NaHCO3-rich solutions. In order to provide the link between surface properties of bacteria and their ability to precipitate Ca carbonate, we used a combination of electrophoretic mobility measurements, surface titration and Ca ion adsorption using dead (autoclaved), inactivated (NaN3 - treated) and live cells at 25 °C as a unction of pH (3-11) and NaCl concentrations (0.01, 0.1, 0.5 M). Zeta potential of both bacteria is identical for active, NaN3-inactivated and dead cells at high ionic strength (0.5 M NaCl). The pH of isoelectric point is below 3 and zeta-potential decreases or remain negative up to pH 11. However, at lower ionic strength (0.1 M and 0.01 M NaCl) for live cells the potential increases towards positive values in the alkaline solutions (pH of 9 to 10). Similar to previous results on cyanobacteria (Martinez et al., 2009) there is a net increase in zeta-potential towards more positive values at pH = 10.4 for active cells. In order to better understand this phenomenon, experiments with different concentration of Ca2+ and HCO3- ions as well as experiments with live cultures in the darkness have been carried out. The presence in solution of Ca2+ (0.01 and 0.001 M) and the absence of light in experiment do not change significantly the potential of the cells. However, the presence in solution of HCO3- strongly reduces the zeta

  8. The Andersen aerobic fitness test

    DEFF Research Database (Denmark)

    Aadland, Eivind; Terum, Torkil; Mamen, Asgeir

    2014-01-01

    of agreement) were 26.7±125.2 m for test 2 vs. test 1 (ptest 3 vs. test 2 (p = .514 for mean difference). The equation to estimate VO2peak suggested by Andersen et al. (2008) showed a poor fit in the present sample; thus, we suggest a new equation: VO2peak = 23......BACKGROUND: High aerobic fitness is consistently associated with a favorable metabolic risk profile in children. Direct measurement of peak oxygen consumption (VO2peak) is often not feasible, thus indirect tests such as the Andersen test are required in many settings. The present study seeks...... to determine the reliability and validity of the Andersen test in 10-year-old children. METHODS: A total of 118 10-year-old children (67 boys and 51 girls) were recruited from one school and performed four VO2peak tests over three weeks: three Andersen tests (indirect) and one continuous progressive treadmill...

  9. Singlet-triplet fission of carotenoid excitation in light-harvesting LH2 complexes of purple phototrophic bacteria.

    Science.gov (United States)

    Klenina, I B; Makhneva, Z K; Moskalenko, A A; Gudkov, N D; Bolshakov, M A; Pavlova, E A; Proskuryakov, I I

    2014-03-01

    The current generally accepted structure of light-harvesting LH2 complexes from purple phototrophic bacteria conflicts with the observation of singlet-triplet carotenoid excitation fission in these complexes. In LH2 complexes from the purple bacterium Allochromatium minutissimum, a drop in the efficiency of carotenoid triplet generation is demonstrated, which correlates with the extent of selective photooxidation of bacteriochlorophylls absorbing at ~850 nm. We conclude that singlet-triplet fission of carotenoid excitation proceeds with participation of these excitonically coupled bacteriochlorophylls. In the framework of the proposed mechanism, the contradiction between LH2 structure and photophysical properties of carotenoids is eliminated. The possibility of singlet-triplet excitation fission involving a third mediator molecule was not considered earlier.

  10. Localized electron transfer rates and microelectrode-based enrichment of microbial communities within a phototrophic microbial mat

    Energy Technology Data Exchange (ETDEWEB)

    Babauta, Jerome T. [Washington State Univ., Pullman, WA (United States); Atci, Erhan [Washington State Univ., Pullman, WA (United States); Ha, Phuc T. [Washington State Univ., Pullman, WA (United States); Lindemann, Stephen R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ewing, Timothy [Washington State Univ., Pullman, WA (United States); Call, Douglas R. [Washington State Univ., Pullman, WA (United States); Fredrickson, James K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Beyenal, Haluk [Washington State Univ., Pullman, WA (United States)

    2014-01-01

    Phototrophic microbial mats frequently exhibit sharp, light-dependent redox gradients that regulate microbial respiration on specific electron acceptors as a function of depth. In this work, a benthic phototrophic microbial mat from Hot Lake, a hypersaline, epsomitic lake located near Oroville in north-central Washington, was used to develop a microscale electrochemical method to study local electron transfer processes within the mat. To characterize the physicochemical variables influencing electron transfer, we initially quantified redox potential, pH, and dissolved oxygen gradients by depth in the mat under photic and aphotic conditions. We further demonstrated that power output of a mat fuel cell was light-dependent. To study local electron transfer processes, we deployed a microscale electrode (microelectrode) with tip size ~20 μm. To enrich a subset of microorganisms capable of interacting with the microelectrode, we anodically polarized the microelectrode at depth in the mat. Subsequently, to characterize the microelectrode- associated community and compare it to the neighboring mat community, we performed amplicon sequencing of the V1-V3 region of the 16S gene. Differences in Bray-Curtis beta diversity, illustrated by large changes in relative abundance at the phylum level, suggested successful enrichment of specific mat community members on the microelectrode surface. The microelectrode-associated community exhibited substantially reduced alpha diversity and elevated relative abundances of Prosthecochloris, Loktanella, Catellibacterium, other unclassified members of Rhodobacteraceae, Thiomicrospira, and Limnobacter, compared with the community at an equivalent depth in the mat. Our results suggest that local electron transfer to an anodically polarized microelectrode selected for a specific microbial population, with substantially more abundance and diversity of sulfur-oxidizing phylotypes compared with the neighboring mat community.

  11. Phototrophic biofilm assembly in microbial-mat-derived unicyanobacterial consortia: model systems for the study of autotroph-heterotroph interactions

    Directory of Open Access Journals (Sweden)

    Jessica K Cole

    2014-04-01

    Full Text Available Microbial autotroph-heterotroph interactions influence biogeochemical cycles on a global scale, but the diversity and complexity of natural systems and their intractability to in situ manipulation make it challenging to elucidate the principles governing these interactions. The study of assembling phototrophic biofilm communities provides a robust means to identify such interactions and evaluate their contributions to the recruitment and maintenance of phylogenetic and functional diversity over time. To examine primary succession in phototrophic communities, we isolated two unicyanobacterial consortia from the microbial mat in Hot Lake, Washington, characterizing the membership and metabolic function of each consortium. We then analyzed the spatial structures and quantified the community compositions of their assembling biofilms. The consortia retained the same suite of heterotrophic species, identified as abundant members of the mat and assigned to Alphaproteobacteria, Gammaproteobacteria, and Bacteroidetes. Autotroph growth rates dominated early in assembly, yielding to increasing heterotroph growth rates late in succession. The two consortia exhibited similar assembly patterns, with increasing relative abundances of members from Bacteroidetes and Alphaproteobacteria concurrent with decreasing relative abundances of those from Gammaproteobacteria. Despite these similarities at higher taxonomic levels, the relative abundances of individual heterotrophic species were substantially different in the developing consortial biofilms. This suggests that, although similar niches are created by the cyanobacterial metabolisms, the resulting webs of autotroph-heterotroph and heterotroph-heterotroph interactions are specific to each primary producer. The relative simplicity and tractability of the Hot Lake unicyanobacterial consortia make them useful model systems for deciphering interspecies interactions and assembly principles relevant to natural

  12. Fit women are not able to use the whole aerobic capacity during aerobic dance.

    Science.gov (United States)

    Edvardsen, Elisabeth; Ingjer, Frank; Bø, Kari

    2011-12-01

    Edvardsen, E, Ingjer, F, and Bø, K. Fit women are not able to use the whole aerobic capacity during aerobic dance. J Strength Cond Res 25(12): 3479-3485, 2011-This study compared the aerobic capacity during maximal aerobic dance and treadmill running in fit women. Thirteen well-trained female aerobic dance instructors aged 30 ± 8.17 years (mean ± SD) exercised to exhaustion by running on a treadmill for measurement of maximal oxygen uptake (VO(2)max) and peak heart rate (HRpeak). Additionally, all subjects performed aerobic dancing until exhaustion after a choreographed videotaped routine trying to reach the same HRpeak as during maximal running. The p value for statistical significance between running and aerobic dance was set to ≤0.05. The results (mean ± SD) showed a lower VO(2)max in aerobic dance (52.2 ± 4.02 ml·kg·min) compared with treadmill running (55.9 ± 5.03 ml·kg·min) (p = 0.0003). Further, the mean ± SD HRpeak was 182 ± 9.15 b·min in aerobic dance and 192 ± 9.62 b·min in treadmill running, giving no difference in oxygen pulse between the 2 exercise forms (p = 0.32). There was no difference in peak ventilation (aerobic dance: 108 ± 10.81 L·min vs. running: 113 ± 11.49 L·min). In conclusion, aerobic dance does not seem to be able to use the whole aerobic capacity as in running. For well endurance-trained women, this may result in a lower total workload at maximal intensities. Aerobic dance may therefore not be as suitable as running during maximal intensities in well-trained females.

  13. Low aerobic fitness in Brazilian adolescents

    Directory of Open Access Journals (Sweden)

    Diego Augusto Santos Silva

    2015-04-01

    Full Text Available INTRODUCTION: aerobic fitness is considered one of the most important components of health-related physical fitness, with low levels related to increased risk of premature death from all causes, especially cardiovascular diseases. OBJECTIVE: to identify the characteristics of adolescents at higher risk of low levels of aerobic fitness. METHODS: the study included 696 adolescents 15-17 years of age enrolled in public high schools of Florianópolis, southern Brazil. This cross-sectional epidemiological study was conducted in Florianópolis, Santa Catarina, Brazil. Aerobic fitness was measured using the modified Canadian Aerobic Fitness Test mCAFT. Sociodemographic gender, age, school grade, paternal and maternal schooling, socioeconomic status, and anthropometric variables body weight, height, triceps and subscapular skinfold thickness, sexual maturation, physical activity, sedentary behavior, and eating habits were collected. RESULTS: it was found that 31.5% of adolescents had low aerobic fitness levels, being higher in boys 49.2% compared to girls 20.6%. Moreover, girls with sedentary behavior, overweight and high body fat percentage were the groups most likely to have inadequate aerobic fitness. In males, the groups most likely to have inadequate aerobic fitness were those whose parents studied more than eight years, those with low levels of physical activity, and those with inadequate nutrition and excessive body fat. CONCLUSION: low aerobic fitness levels were present in one third of adolescents and was more prevalent in boys. Lifestyle changes, including replacement of sedentary behaviors by physical and sport activities , may assist in improving the aerobic fitness of Brazilian adolescents.

  14. Neuromodulation of Aerobic Exercise—A Review

    Directory of Open Access Journals (Sweden)

    Saskia eHeijnen

    2016-01-01

    Full Text Available Running, and aerobic exercise in general, is a physical activity that increasingly many people engage in but that also has become popular as a topic for scientific research. Here we review the available studies investigating whether and to which degree aerobic exercise modulates hormones, amino acids, and neurotransmitters levels. In general, it seems that factors such as genes, gender, training status, and hormonal status need to be taken into account to gain a better understanding of the neuromodular underpinnings of aerobic exercise. More research using longitudinal studies and considering individual differences is necessary to determine actual benefits. We suggest that, in order to succeed, aerobic exercise programs should include optimal periodization, prevent overtraining and be tailored to interindividual differences, including neuro-developmental and genetically-based factors.

  15. Temperature effect on aerobic denitrification and nitrification

    Institute of Scientific and Technical Information of China (English)

    XIE Shu-guang; ZHANG Xiao-jian; WANG Zhan-sheng

    2003-01-01

    Nitrogen loss without organic removal in biofilter was observed and its possible reason was explained. A lower hydraulic loading could improve aerobic denitrification rate. Aerobic denitrification was seriously affected by low temperature(below 10oC). However, nitrification rate remained high when the temperature dropped from 15oC to5oC. It seemed the autotrophic biofilm in BAF could alleviate the adverse effect of low temperature.

  16. Combined stable isotope, proteomic, metabolomics, and spatial specific analysis to track carbon flow through a hypersaline phototrophic microbial mat

    Science.gov (United States)

    Moran, J.; Cory, A.; Riha, K. M.; Huang, E. L.; Gritsenko, M. A.; Kim, Y. M.; Metz, T. O.; Lipton, M. S.

    2014-12-01

    Tracking labeled substrates through microbial mat systems can help elucidate carbon dynamics, species interactions, and niche partitioning, but the inherent microbial complexity of these systems makes them difficult to probe with single analytical techniques. Here we use a combination of different tools to track three labeled substrates through a benthic phototrophic mat from Hot Lake. Hot Lake is a hypersaline, meromictic lake located in an endorheic basin in north-central Washington which, despite extreme salinity and seasonal water temperatures (> 55 ˚C), hosts dense, phototrophic benthic microbial mats. Cyanobacteria are the dominant CO2-fixing organisms in the system and we seek to understand the spatial and metabolic controls on how the carbon initially fixed by mat cyanobacteria is transferred to associated heterotrophic populations spread throughout the mat strata. We performed ex situ incubations over a complete diel cycle with 13C labeled bicarbonate, acetate, and glucose. Traditional elemental analysis IRMS provided an estimate of bulk label uptake to total biomass and showed that both bicarbonate and acetate were incorporated only during daylight while glucose uptake was nearly constant through the cycle. Spatially resolved isotope analysis using laser ablation IRMS showed distinctive patterns between the different substrates with bicarbonate having highest uptake in the top third of the mat, acetate uptake focused near the mat's center, and glucose showing similar uptake at all mat depths. Proteomic analysis showed a longer lag in substrate conversion to protein than to biomass and a distinct spike in the number of labeled peptides in the bicarbonate incubation near the end of the diel cycle. Proteomic analysis confirmed that photosynthetic organisms showed the highest rates of label conversion to protein but heterotrophic organisms also incorporated label into their peptides. Metabolomic analysis demonstrated the high conversion of organic substrates

  17. Metatranscriptomic analysis of a high-sulfide aquatic spring reveals insights into sulfur cycling and unexpected aerobic metabolism

    Directory of Open Access Journals (Sweden)

    Anne M. Spain

    2015-09-01

    Full Text Available Zodletone spring is a sulfide-rich spring in southwestern Oklahoma characterized by shallow, microoxic, light-exposed spring water overlaying anoxic sediments. Previously, culture-independent 16S rRNA gene based diversity surveys have revealed that Zodletone spring source sediments harbor a highly diverse microbial community, with multiple lineages putatively involved in various sulfur-cycling processes. Here, we conducted a metatranscriptomic survey of microbial populations in Zodletone spring source sediments to characterize the relative prevalence and importance of putative phototrophic, chemolithotrophic, and heterotrophic microorganisms in the sulfur cycle, the identity of lineages actively involved in various sulfur cycling processes, and the interaction between sulfur cycling and other geochemical processes at the spring source. Sediment samples at the spring’s source were taken at three different times within a 24-h period for geochemical analyses and RNA sequencing. In depth mining of datasets for sulfur cycling transcripts revealed major sulfur cycling pathways and taxa involved, including an unexpected potential role of Actinobacteria in sulfide oxidation and thiosulfate transformation. Surprisingly, transcripts coding for the cyanobacterial Photosystem II D1 protein, methane monooxygenase, and terminal cytochrome oxidases were encountered, indicating that genes for oxygen production and aerobic modes of metabolism are actively being transcribed, despite below-detectable levels (<1 µM of oxygen in source sediment. Results highlight transcripts involved in sulfur, methane, and oxygen cycles, propose that oxygenic photosynthesis could support aerobic methane and sulfide oxidation in anoxic sediments exposed to sunlight, and provide a viewpoint of microbial metabolic lifestyles under conditions similar to those seen during late Archaean and Proterozoic eons.

  18. Metatranscriptomic analysis of a high-sulfide aquatic spring reveals insights into sulfur cycling and unexpected aerobic metabolism

    Science.gov (United States)

    Elshahed, Mostafa S.; Najar, Fares Z.; Krumholz, Lee R.

    2015-01-01

    Zodletone spring is a sulfide-rich spring in southwestern Oklahoma characterized by shallow, microoxic, light-exposed spring water overlaying anoxic sediments. Previously, culture-independent 16S rRNA gene based diversity surveys have revealed that Zodletone spring source sediments harbor a highly diverse microbial community, with multiple lineages putatively involved in various sulfur-cycling processes. Here, we conducted a metatranscriptomic survey of microbial populations in Zodletone spring source sediments to characterize the relative prevalence and importance of putative phototrophic, chemolithotrophic, and heterotrophic microorganisms in the sulfur cycle, the identity of lineages actively involved in various sulfur cycling processes, and the interaction between sulfur cycling and other geochemical processes at the spring source. Sediment samples at the spring’s source were taken at three different times within a 24-h period for geochemical analyses and RNA sequencing. In depth mining of datasets for sulfur cycling transcripts revealed major sulfur cycling pathways and taxa involved, including an unexpected potential role of Actinobacteria in sulfide oxidation and thiosulfate transformation. Surprisingly, transcripts coding for the cyanobacterial Photosystem II D1 protein, methane monooxygenase, and terminal cytochrome oxidases were encountered, indicating that genes for oxygen production and aerobic modes of metabolism are actively being transcribed, despite below-detectable levels (oxygen in source sediment. Results highlight transcripts involved in sulfur, methane, and oxygen cycles, propose that oxygenic photosynthesis could support aerobic methane and sulfide oxidation in anoxic sediments exposed to sunlight, and provide a viewpoint of microbial metabolic lifestyles under conditions similar to those seen during late Archaean and Proterozoic eons. PMID:26417542

  19. Impact of a simulated oil spill on benthic phototrophs and nitrogen-fixing bacteria in mudflat mesocosms.

    Science.gov (United States)

    Chronopoulou, Panagiota-Myrsini; Fahy, Anne; Coulon, Frédéric; Païssé, Sandrine; Goñi-Urriza, Marisol; Peperzak, Louis; Acuña Alvarez, Laura; McKew, Boyd A; Lawson, Tracy; Timmis, Kenneth N; Duran, Robert; Underwood, Graham J C; McGenity, Terry J

    2013-01-01

    Coastal and estuarine ecosystems are highly susceptible to crude oil pollution. Therefore, in order to examine the resilience of benthic phototrophs that are pivotal to coastal ecosystem functioning, we simulated an oil spill in tidal mesocosms consisting of intact sediment cores from a mudflat at the mouth of the Colne Estuary, UK. At day 21, fluorescence imaging revealed a bloom of cyanobacteria on the surface of oiled sediment cores, and the upper 1.5 cm thick sediment had 7.2 times more cyanobacterial and 1.7 times more diatom rRNA sequences when treated with oil. Photosystem II operating efficiency (Fq'/Fm') was significantly reduced in oiled sediments at day 7, implying that the initial diatom-dominated community was negatively affected by oil, but this was no longer apparent by day 21. Oil addition significantly reduced numbers of the key deposit feeders, and the decreased grazing pressure is likely to be a major factor in the increased abundance of both diatoms and cyanobacteria. By day 5 concentrations of dissolved inorganic nitrogen were significantly lower in oiled mesocosms, likely resulting in the observed increase in nifH-containing, and therefore potentially dinitrogen-fixing, cyanobacteria. Thus, indirect effects of oil, rather than direct inhibition, are primarily responsible for altering the microphytobenthos.

  20. CO₂ assimilation in the chemocline of Lake Cadagno is dominated by a few types of phototrophic purple sulfur bacteria.

    Science.gov (United States)

    Storelli, Nicola; Peduzzi, Sandro; Saad, Maged M; Frigaard, Niels-Ulrik; Perret, Xavier; Tonolla, Mauro

    2013-05-01

    Lake Cadagno is characterized by a compact chemocline that harbors high concentrations of various phototrophic sulfur bacteria. Four strains representing the numerically most abundant populations in the chemocline were tested in dialysis bags in situ for their ability to fix CO₂. The purple sulfur bacterium Candidatus 'Thiodictyon syntrophicum' strain Cad16(T) had the highest CO₂ assimilation rate in the light of the four strains tested and had a high CO₂ assimilation rate even in the dark. The CO₂ assimilation of the population represented by strain Cad16(T) was estimated to be up to 25% of the total primary production in the chemocline. Pure cultures of strain Cad16(T) exposed to cycles of 12 h of light and 12 h of darkness exhibited the highest CO₂ assimilation during the first 4 h of light. The draft genome sequence of Cad16(T) showed the presence of cbbL and cbbM genes, which encode form I and form II of RuBisCO, respectively. Transcription analyses confirmed that, whereas cbbM remained poorly expressed throughout light and dark exposure, cbbL expression varied during the light-dark cycle and was affected by the available carbon sources. Interestingly, the peaks in cbbL expression did not correlate with the peaks in CO₂ assimilation.

  1. Rhodobacter megalophilus sp. nov., a phototroph from the Indian Himalayas possessing a wide temperature range for growth.

    Science.gov (United States)

    Arunasri, K; Venkata Ramana, V; Spröer, C; Sasikala, Ch; Ramana, Ch V

    2008-08-01

    Two strains of phototrophic, purple non-sulfur bacteria capable of growing at low temperatures (5 degrees C) were isolated from the Himalayas. The two strains showed positive phototaxis and grew over a relatively wide temperature range (5-40 degrees C). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain JA194T clustered with members of the genus Rhodobacter. Strain JA194T showed highest 16S rRNA gene sequence similarity with Rhodobacter sphaeroides DSM 158T (99 %). However, DNA-DNA hybridization experiments between Rba. sphaeroides DSM 158T and strain JA194T revealed a level of relatedness of only 67 %. The DNA base composition of strain JA194T was 66.67 mol% G+C (by HPLC). Based on 16S rRNA gene sequence analysis, morphological, physiological, Fourier transform infrared fingerprinting and DNA-DNA hybridization studies, strain JA194T (=KCTC 5602T =JCM 14598T) is sufficiently different from other Rhodobacter species to merit its description as the type strain of a novel species, for which the name Rhodobacter megalophilus sp. nov. is proposed.

  2. Phototrophic Growth and Accumulation of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate by Purple Nonsulfur Bacterium Rhodopseudomonas palustris SP5212

    Directory of Open Access Journals (Sweden)

    M. Mukhopadhyay

    2013-01-01

    Full Text Available The ability of the phototrophic bacterium Rhodopseudomonas palustris SP5212 to produce polyhydroxyalkanoates (PHAs, poly(3-hydroxybutyrate-co-3-hydroxyvalerate [P(3HB-co-3HV] in particular was, assessed in acetate medium supplemented with hydroxybutyrate and valerate as cosubstrates. The isolate accumulated the polymer accounting for some 49.06% and 30% of cell dry weight when grown in hydroxybutyrate and valerate, respectively. PHA accumulation as well as 3HV monomer incorporation (30 mol% was maximum at 0.1% hydroxybutyrate, while valerate at 0.1% and 0.3% was suitable for total polymer accumulation and 3HV monomer incorporation, respectively. Cosupplementation of hydroxybutyrate and valerate in the ratio of 3 : 1 led to the accumulation of PHA accounting for 54% of cell dry weight, which contained more than 50 mol% of 3HV monomer. Moreover, the biphasic cultivation conditions with hydroxybutyrate as cosubstrate have improved the quality as well as quantity of the accumulated copolymer significantly.

  3. Mechanism of Kenaf Retting Using Aerobes

    Institute of Scientific and Technical Information of China (English)

    卢士森; 陈季华; 黄秀宝

    2001-01-01

    The experimental results showed that the duration of microbial retting processing of kenaf fibers by using aerobic microbe was four times shorter than that by using anaerobic microbe. The residual gum percentage,breaking strength, breaking elongation and linear density of aerobic retted kenaf bundle fibers did not show significantly difference with that of anaerobic retted kenaf bundle fibers by ANOVA-Tukey's studentized test at a = 5% except for the softness. The bioenergetic principle and the calculation of the amount of ATP produced during the decomposition processing of kenaf gums were used to explain why the retting duration in the case of using aerobic microbes was much shorter than that of using anaerobic microbes.

  4. Therapeutic aspects of aerobic dance participation.

    Science.gov (United States)

    Estivill, M

    1995-01-01

    An ethnographic analysis of aerobic dance exercise culture was conducted to determine the impact of the culture on the mind-body connection. After a review of the predominant theories on the relationship between vigorous exercise and elevated mood, aerobic dance participants' experiences are reported to illustrate how cognitive experience and self-esteem may be influenced. Interviews revealed that some participants achieved a pleasantly altered state of consciousness and respite from depression and stress. The relationship of the work ethic to achievement of participant satisfaction is underscored.

  5. Distributions of phospholipid and glycolipid fatty acids in two strains of different functional Erythrobacter sp.isolated from South China Sea

    Institute of Scientific and Technical Information of China (English)

    Huan YANG; Xiangru MA; Qiang LI; Nianzhi JIAO; Shucheng XIE

    2009-01-01

    The comparison of the fatty acids between aerobic anoxygenic phototrophic bacteria (AAPB) and their phylogenetic relatives has been a fascinating but yet enigmatic topic, enhancing our understanding of physiological variations between these evolutionarily related microorganisms. Two strains of marine bacteria, both phylogenetically falling into Erythrobacter sp., were isolated from the South China Sea, and demonstrated, respectively, to be an aerobic anoxygenic phototrophic bacteria (AAPB) (JL475) which is capable of anoxygenic photosynthesis via BChl a, and an obligate heterotroph (JL316) with a lack of BChl a, on the basis ofphylogenetic analysis and pure culture cultivation. Phospholipid fatty acids (PLFA) and glycolipid fatty acids (GLFA) of the two swains were extracted and analyzed by gas chromatographymass spectrometry. The PLFA in JL475 AAPB arecharacterized by C18:1, C18:2w7,13 and C18:0, with the C18:2w7,13 being a specific compound for AAPB and in particular for Erythrobacter longus and some of its phylogenetically closely related relatives. The JL316 strain is characterized in PLFA by the presence of C18:1, C16:1and C16:1, and in particular C17:1. GLFA do not show any discrimination between the two strains. Four α,wdicarboxylic acids, including 1,8-octanedioic acid, 1,9-nonanedioic acid, 1,10-decanedioic acid and 1,11-undecanedioic acid, are present only in JL316 GLFA, presumably derived from metabolic products. C14-C16 2-hydroxy fatty acids were found in the two strains, probably assuming a similar function of their LPS in outer membranes.

  6. Aerobic exercise training in modulation of aerobic physical fitness and balance of burned patients

    OpenAIRE

    Ali, Zizi M. Ibrahim; El-Refay, Basant H.; Ali, Rania Reffat

    2015-01-01

    [Purpose] This study aimed to determine the impact of aerobic exercise on aerobic capacity, balance, and treadmill time in patients with thermal burn injury. [Subjects and Methods] Burned adult patients, aged 20–40 years (n=30), from both sexes, with second degree thermal burn injuries covering 20–40% of the total body surface area (TBSA), were enrolled in this trial for 3 months. Patients were randomly divided into; group A (n=15), which performed an aerobic exercise program 3 days/week for ...

  7. Strength training and aerobic exercise training for muscle disease (Review)

    NARCIS (Netherlands)

    Voet, N.B.M.; Kooi, E.L. van der; Riphagen, I.I.; Lindeman, E.; Engelen, B.G.M. van; Geurts, A.C.H.

    2010-01-01

    BACKGROUND: Strength training or aerobic exercise programmes might optimise muscle and cardiorespiratory function and prevent additional disuse atrophy and deconditioning in people with a muscle disease. OBJECTIVES: To examine the safety and efficacy of strength training and aerobic exercise trainin

  8. Comparative proteomics and activity of a green sulfur bacterium across the water column of Lake Cadagno, Switzerland

    DEFF Research Database (Denmark)

    Habicht, Kirsten Silvia; Miller, Mette; Cox, Raymond Pickett

    2011-01-01

    Primary production in the meromictic Lake Cadagno, Switzerland, is dominated by anoxygenic photosynthesis. The green sulfur bacterium Chlorobium clathratiforme is the dominant phototrophic organism in the lake, comprising more than half of the bacterial population, and its biomass increases 3...

  9. Aerobic exercise in fibromyalgia: a practical review.

    Science.gov (United States)

    Thomas, Eric N; Blotman, Francis

    2010-07-01

    The objective of the study was to determine the current evidence to support guidelines for aerobic exercise (AE) and fibromyalgia (FM) in practice, and to outline specific research needs in these areas. Data sources consisted of a PubMed search, 2007 Cochrane Data Base Systematic review, 2008 Ottawa panel evidence-based clinical practice guidelines, as well as additional references found from the initial search. Study selection included randomized clinical trials that compared an aerobic-only exercise intervention (land or pool based) with an untreated control, a non-exercise intervention or other exercise programs in patients responding to the 1990 American College of Rheumatology criteria for FM. The following outcome data were obtained: pain, tender points, perceived improvement in FM symptoms such as the Fibromyalgia Impact Questionnaire total score (FIQ), physical function, depression (e.g., Beck Depression Inventory, FIQ subscale for depression), fatigue and sleep were extracted from 19 clinical trials that considered the effects of aerobic-only exercise in FM patients. Data synthesis shows that there is moderate evidence of important benefit of aerobic-only exercise in FM on physical function and possibly on tender points and pain. It appears to be sufficient evidence to support the practice of AE as a part of the multidisciplinary management of FM. However, future studies must be more adequately sized, homogeneously assessed, and monitored for adherence, to draw definitive conclusions.

  10. Integrated anaerobic and aerobic treatment of sewage.

    NARCIS (Netherlands)

    Kaijun Wang,

    1994-01-01

    This thesis describes results of investigations dealing with sequential concept of anaerobic-aerobic treatment of municipal wastewater. The main purposes of the study were 1) to develop a proper anaerobic hydrolytic pretreatment unit, consisting of a Hydrolysis Upflow Sludge Bed (HUSB-) reactor and

  11. Intraspecific variation in aerobic and anaerobic locomotion

    DEFF Research Database (Denmark)

    Svendsen, Jon Christian; Tirsgård, Bjørn; Cordero, Gerardo A.;

    2015-01-01

    Intraspecific variation and trade-off in aerobic and anaerobic traits remain poorly understood in aquatic locomotion. Using gilthead sea bream (Sparus aurata) and Trinidadian guppy (Poecilia reticulata), both axial swimmers, this study tested four hypotheses: (1) gait transition from steady...

  12. Ventilation and Speech Characteristics during Submaximal Aerobic Exercise

    Science.gov (United States)

    Baker, Susan E.; Hipp, Jenny; Alessio, Helaine

    2008-01-01

    Purpose: This study examined alterations in ventilation and speech characteristics as well as perceived dyspnea during submaximal aerobic exercise tasks. Method: Twelve healthy participants completed aerobic exercise-only and simultaneous speaking and aerobic exercise tasks at 50% and 75% of their maximum oxygen consumption (VO[subscript 2] max).…

  13. Aerobic exercise training in modulation of aerobic physical fitness and balance of burned patients.

    Science.gov (United States)

    Ali, Zizi M Ibrahim; El-Refay, Basant H; Ali, Rania Reffat

    2015-03-01

    [Purpose] This study aimed to determine the impact of aerobic exercise on aerobic capacity, balance, and treadmill time in patients with thermal burn injury. [Subjects and Methods] Burned adult patients, aged 20-40 years (n=30), from both sexes, with second degree thermal burn injuries covering 20-40% of the total body surface area (TBSA), were enrolled in this trial for 3 months. Patients were randomly divided into; group A (n=15), which performed an aerobic exercise program 3 days/week for 60 min and participated in a traditional physical therapy program, and group B (n=15), which only participated in a traditional exercise program 3 days/week. Maximal aerobic capacity, treadmill time, and Berg balance scale were measured before and after the study. [Results] In both groups, the results revealed significant improvements after treatment in all measurements; however, the improvement in group A was superior to that in group B. [Conclusion] The results provide evidence that aerobic exercises for adults with healed burn injuries improve aerobic physical fitness and balance.

  14. Taxonomic and Functional Metagenomic Signature of Turfs in the Abrolhos Reef System (Brazil).

    Science.gov (United States)

    Walter, Juline M; Tschoeke, Diogo A; Meirelles, Pedro M; de Oliveira, Louisi; Leomil, Luciana; Tenório, Márcio; Valle, Rogério; Salomon, Paulo S; Thompson, Cristiane C; Thompson, Fabiano L

    2016-01-01

    Turfs are widespread assemblages (consisting of microbes and algae) that inhabit reef systems. They are the most abundant benthic component in the Abrolhos reef system (Brazil), representing greater than half the coverage of the entire benthic community. Their presence is associated with a reduction in three-dimensional coral reef complexity and decreases the habitats available for reef biodiversity. Despite their importance, the taxonomic and functional diversity of turfs remain unclear. We performed a metagenomics and pigments profile characterization of turfs from the Abrolhos reefs. Turf microbiome primarily encompassed Proteobacteria (mean 40.57% ± s.d. 10.36, N = 1.548,192), Cyanobacteria (mean 35.04% ± s.d. 15.5, N = 1.337,196), and Bacteroidetes (mean 11.12% ± s.d. 4.25, N = 424,185). Oxygenic and anoxygenic phototrophs, chemolithotrophs, and aerobic anoxygenic phototrophic (AANP) bacteria showed a conserved functional trait of the turf microbiomes. Genes associated with oxygenic photosynthesis, AANP, sulfur cycle (S oxidation, and DMSP consumption), and nitrogen metabolism (N2 fixation, ammonia assimilation, dissimilatory nitrate and nitrite ammonification) were found in the turf microbiomes. Principal component analyses of the most abundant taxa and functions showed that turf microbiomes differ from the other major Abrolhos benthic microbiomes (i.e., corals and rhodoliths) and seawater. Taken together, these features suggest that turfs have a homogeneous functional core across the Abrolhos Bank, which holds diverse microbial guilds when comparing with other benthic organisms.

  15. Acute effects of aerobic exercise promote learning

    OpenAIRE

    Renza Perini; Marta Bortoletto; Michela Capogrosso; Anna Fertonani; Carlo Miniussi

    2016-01-01

    The benefits that physical exercise confers on cardiovascular health are well known, whereas the notion that physical exercise can also improve cognitive performance has only recently begun to be explored and has thus far yielded only controversial results. In the present study, we used a sample of young male subjects to test the effects that a single bout of aerobic exercise has on learning. Two tasks were run: the first was an orientation discrimination task involving the primary visual cor...

  16. Experimental evidence for aerobic bio-denitrification

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Nitrate pollution of groundwater is paid more and more attention for its hazardous to environments and human health. A strain of DN11 was isolated from soil and used in the laboratory columns filled with various media for nitrate removal. The experimental results showed that DN11could reduce nitrate at different rates in different media under the aerobic condition. The mechanism for nitrate removal with DN11 is explained meanwhile.

  17. Aerobic Exercise, Estrogens, and Breast Cancer Risk

    Science.gov (United States)

    2011-11-01

    include early age at menarche, late age at menopause and first childbirth, nulliparity, family history of breast cancer, benign breast disease, and non...et al. (24), a four-cycle intervention consisting of moderate-intensity aerobic exercise in combination with a caloric restrictive diet resulted in...vigorous exercise intervention independent of diet restriction and weight loss. We specifically sought to determine if the exercise intervention would

  18. Enhancement of phototrophic hydrogen production by Rhodobacter sphaeroides ZX-5 using a novel strategy - shaking and extra-light supplementation approach

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xu; Wang, Yong-Hong; Zhang, Si-Liang; Chu, Ju; Zhang, Ming; Huang, Ming-Zhi; Zhuang, Ying-Ping [State Key Laboratory of Bioreactor Engineering, P.O. Box 329, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237 (China)

    2009-12-15

    Biohydrogen has gained attention due to its potential as a sustainable alternative to conventional methods for hydrogen production. In this study, the effect of light intensity as well as cultivation method (standing- and shaking-culture) on the cell growth and hydrogen production of Rhodobacter sphaeroides ZX-5 were investigated in 38-ml anaerobic photobioreactor with RCVBN medium. Thus, a novel shaking and extra-light supplementation (SELS) approach was developed to enhance the phototrophic H{sub 2} production by R. sphaeroides ZX-5 using malate as the sole carbon source. The optimum illumination condition for shaking-culture by strain ZX-5 increased to 7000-8000 lux, markedly higher than that for standing-culture (4000-5000 lux). Under shaking and elevated illumination (7000-8000 lux), the culture was effective in promoting photo-H{sub 2} production, resulting in a 59% and 56% increase of the maximum and average hydrogen production rate, respectively, in comparison with the culture under standing and 4000-5000 lux conditions. The highest hydrogen-producing rate of 165.9 ml H{sub 2}/l h was observed under the application of SELS approach. To our knowledge, this record is currently the highest hydrogen production rate of non-immobilized purple non-sulphur (PNS) bacteria. This optimal performance of photo-H{sub 2} production using SELS approach is a favorable choice of sustainable and economically feasible strategy to improve phototrophic H{sub 2} production efficiency. (author)

  19. Confocal laser scanning microscopy coupled to a spectrofluorometric detector as a rapid tool for determining the in vivo effect of metals on phototrophic bacteria.

    Science.gov (United States)

    Burnat, Mireia; Diestra, Elia; Esteve, Isabel; Solé, Antonio

    2010-01-01

    In this paper, we determine for the first time the in vivo effect of heavy metals in a phototrophic bacterium. We used Confocal Laser Scanning Microscopy coupled to a spectrofluorometric detector as a rapid technique to measure pigment response to heavy-metal exposure. To this end, we selected lead and copper (toxic and essential metals) and Microcoleus sp. as the phototrophic bacterium because it would be feasible to see this cyanobacterium as a good biomarker, since it covers large extensions of coastal sediments. The results obtained demonstrate that, while cells are still viable, pigment peak decreases whereas metal concentration increases (from 0.1 to 1 mM Pb). Pigments are totally degraded when cultures were polluted with lead and copper at the maximum doses used (25 mM Pb(NO(3))(2) and 10 mM CuSO(4)). The aim of this study was also to identify the place of metal accumulation in Microcoleus cells. Element analysis of this cyanobacterium in the above mentioned conditions determined by Energy Dispersive X-ray microanalysis (EDX) coupled to Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), shows that Pb (but not Cu) accumulates externally and internally in cells.

  20. Warming-induced changes in denitrifier community structure modulate the ability of phototrophic river biofilms to denitrify

    Energy Technology Data Exchange (ETDEWEB)

    Boulêtreau, Stéphanie, E-mail: stephanie.bouletreau@univ-tlse3.fr [Université de Toulouse, UPS, INP, EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), 118 route de Narbonne, F-31062 Toulouse (France); CNRS, EcoLab, F-31062 Toulouse (France); Lyautey, Emilie [Université de Toulouse, UPS, INP, EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), 118 route de Narbonne, F-31062 Toulouse (France); CNRS, EcoLab, F-31062 Toulouse (France); Dubois, Sophie [Université de Bordeaux, EPOC - OASU, UMR 5805, Station Marine d' Arcachon, 2 rue du Professeur Jolyet, 33120 Arcachon (France); Compin, Arthur [Université de Toulouse, UPS, INP, EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), 118 route de Narbonne, F-31062 Toulouse (France); CNRS, EcoLab, F-31062 Toulouse (France); Delattre, Cécile; Touron-Bodilis, Aurélie [EDF Recherche et Développement, LNHE (Laboratoire National d' Hydraulique et Environnement), 6 quai Watier, F-78401 Chatou (France); Mastrorillo, Sylvain [Université de Toulouse, UPS, INP, EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), 118 route de Narbonne, F-31062 Toulouse (France); CNRS, EcoLab, F-31062 Toulouse (France); Garabetian, Frédéric [Université de Bordeaux, EPOC - OASU, UMR 5805, Station Marine d' Arcachon, 2 rue du Professeur Jolyet, 33120 Arcachon (France)

    2014-01-01

    Microbial denitrification is the main nitrogen removing process in freshwater ecosystems. The aim of this study was to show whether and how water warming (+ 2.5 °C) drives bacterial diversity and structuring and how bacterial diversity affects denitrification enzymatic activity in phototrophic river biofilms (PRB). We used water warming associated to the immediate thermal release of a nuclear power plant cooling circuit to produce natural PRB assemblages on glass slides while testing 2 temperatures (mean temperature of 17 °C versus 19.5 °C). PRB were sampled at 2 sampling times during PRB accretion (6 and 21 days) in both temperatures. Bacterial community composition was assessed using ARISA. Denitrifier community abundance and denitrification gene mRNA levels were estimated by q-PCR and qRT-PCR, respectively, of 5 genes encoding catalytic subunits of the denitrification key enzymes. Denitrification enzyme activity (DEA) was measured by the acetylene-block assay at 20 °C. A mean water warming of 2.5 °C was sufficient to produce contrasted total bacterial and denitrifier communities and, therefore, to affect DEA. Indirect temperature effect on DEA may have varied between sampling time, increasing by up to 10 the denitrification rate of 6-day-old PRB and decreasing by up to 5 the denitrification rate of 21-day-old PRB. The present results suggest that indirect effects of warming through changes in bacterial community composition, coupled to the strong direct effect of temperature on DEA already demonstrated in PRB, could modulate dissolved nitrogen removal by denitrification in rivers and streams. - Highlights: •We produced river biofilms in 2 mean temperature conditions: 17 vs 19.5 °C. •We compared their denitrifiers' structuring and functioning in 6d- and 21d-old biofilms. •A difference of 2.5 °C produced contrasted denitrifier communities. •The indirect temperature effect on denitrification activity shifted between biofilm age.

  1. [Cardiovascular protection and mechanisms of actions of aerobic exercise].

    Science.gov (United States)

    Hou, Zuo-Xu; Zhang, Yuan; Gao, Feng

    2014-08-01

    It is well established that aerobic exercise exerts beneficial effect on cardiovascular system, but the underlying mechanisms are yet to be elucidated. Recent studies have shown that aerobic exercise ameliorates insulin resistance, inflammation and mitochondrial dysfunction which play important roles in the development of cardiovascular disease. In this review, we discussed the underlying mechanisms of the cardioprotective role of aerobic exercise, especially the latest progress in this field.

  2. Intensity Thresholds for Aerobic Exercise–Induced Hypoalgesia

    OpenAIRE

    Naugle, Kelly M.; Naugle, Keith E.; Fillingim, Roger B; Samuels, Brian; Riley, Joseph L.

    2014-01-01

    Despite many studies investigating exercise-induced hypoalgesia, there is limited understanding of the optimal intensity of aerobic exercise in producing hypoalgesic effects across different types of pain stimuli. Given that not all individuals are willing or capable of engaging in high intensity aerobic exercise, whether moderate intensity aerobic exercise is associated with a hypoalgesic response and whether this response generalizes to multiple pain induction techniques needs to be substan...

  3. Perfection aerobic possibilities of athletes in sport dance.

    Directory of Open Access Journals (Sweden)

    Lee Bo

    2011-04-01

    Full Text Available The organized analysis to functions of the aerobic metabolism of the sport dancers. They are determined reduced components of the aerobic metabolism of partners (male and female. The motivated directivity of the training means and program for development component of the aerobic functions skilled athlete in sport dance. It is proved that loading that is used in training process by sport dances must have a character of cardiorespiratory system.

  4. Research on aerobics classes influence on physical prepareduess of students.

    Directory of Open Access Journals (Sweden)

    Krasulia M. А.

    2011-04-01

    Full Text Available Physical skills of female students doing aerobics have been studied. 165 female students aged 17-18 divided into three groups of 55 each have taken part in the experiment. Groups have been trained according to different methods conventionally called 'power aerobics', 'dance aerobics' and 'jump aerobics'. Level of female students' physical skills has been determined by the results of seven tests in the beginning of an academic year and after six-months term. Mathematical treatment of the results has been carried out. The most preferable as to improving physical skills level method has been discovered to be the one aimed on power abilities development method.

  5. Aerobic capacity related to cardiac size in young children

    DEFF Research Database (Denmark)

    Dencker, M; Wollmer, P; Karlsson, M

    2013-01-01

    Aerobic capacity, defined as peak oxygen uptake (VO2PEAK), is generally considered to be the best single marker for aerobic fitness. We assessed if VO2PEAK is related to different cardiac dimensions in healthy young children on a population base.......Aerobic capacity, defined as peak oxygen uptake (VO2PEAK), is generally considered to be the best single marker for aerobic fitness. We assessed if VO2PEAK is related to different cardiac dimensions in healthy young children on a population base....

  6. Screening and identification of aerobic denitrifiers

    Science.gov (United States)

    Shao, K.; Deng, H. M.; Chen, Y. T.; Zhou, H. J.; Yan, G. X.

    2016-08-01

    With the standards of the effluent quality more stringent, it becomes a quite serious problem for municipalities and industries to remove nitrogen from wastewater. Bioremediation is a potential method for the removal of nitrogen and other pollutants because of its high efficiency and low cost. Seven predominant aerobic denitrifiers were screened and characterized from the activated sludge in the CAST unit. Some of these strains removed 87% nitrate nitrogen at least. Based on their phenotypic and phylogenetic characteristics, the isolates were identified as the genera of Ralstonia, Achromobacter, Aeromonas and Enterobacter.

  7. Intraspecific variation in aerobic and anaerobic locomotion

    DEFF Research Database (Denmark)

    Svendsen, Jon Christian; Tirsgård, Bjørn; Cordero, Gerardo A.;

    2015-01-01

    Intraspecific variation and trade-off in aerobic and anaerobic traits remain poorly understood in aquatic locomotion. Using gilthead sea bream (Sparus aurata) and Trinidadian guppy (Poecilia reticulata), both axial swimmers, this study tested four hypotheses: (1) gait transition from steady...... to unsteady (i.e., burst-assisted) swimming is associated with anaerobic metabolism evidenced as excess post exercise oxygen consumption (EPOC); (2) variation in swimming performance (critical swimming speed; U crit) correlates with metabolic scope (MS) or anaerobic capacity (i.e., maximum EPOC); (3...

  8. Characterization and aerobic biodegradation of selected monoterpenes

    Energy Technology Data Exchange (ETDEWEB)

    Misra, G.; Pavlostathis, S.G.; Li, J.; Purdue, E.M. [Georgia Institute of Technology, Atlanta, GA (United States)

    1996-12-31

    Monoterpenes are biogenic chemicals and occur in abundance in nature. Large-scale industrial use of these chemicals has recently been initiated in an attempt to replace halogenated solvents and chlorofluorocarbons which have been implicated in the stratospheric depletion of ozone. This study examined four hydrocarbon monoterpenes (d-limonene, {alpha}-pinene, {gamma}-terpinene, and terpinolene) and four alcohols (arbanol, linalool, plinol, and {alpha}-terpineol). Water solubility, vapor pressure, and octanol/water partition coefficients were estimated. Aerobic biodegradability tests were conducted in batch reactors by utilizing forest soil extract and enriched cultures as inoculum. The hydrophobic nature and high volatility of the hydrocarbons restricted the investigation to relatively low aqueous concentrations. Each monoterpene was analyzed with a gas chromatograph equipped with a flame ionization detector after extraction from the aqueous phase with isooctane. Terpene mineralization was tested by monitoring liquid-phase carbon, CO{sub 2} production and biomass growth. All four hydrocarbons and two alcohols readily degraded under aerobic conditions. Plinol resisted degradation in assays using inocula from diverse sources, while arbanol degraded very slowly. The intrinsic biokinetics coefficients for the degradation of d-limonene and {alpha}-terpineol were estimated by using cultures enriched with the respective monoterpenes. Monoterpene biodegradation followed Monod kinetics.

  9. Acute effects of aerobic exercise promote learning.

    Science.gov (United States)

    Perini, Renza; Bortoletto, Marta; Capogrosso, Michela; Fertonani, Anna; Miniussi, Carlo

    2016-05-05

    The benefits that physical exercise confers on cardiovascular health are well known, whereas the notion that physical exercise can also improve cognitive performance has only recently begun to be explored and has thus far yielded only controversial results. In the present study, we used a sample of young male subjects to test the effects that a single bout of aerobic exercise has on learning. Two tasks were run: the first was an orientation discrimination task involving the primary visual cortex, and the second was a simple thumb abduction motor task that relies on the primary motor cortex. Forty-four and forty volunteers participated in the first and second experiments, respectively. We found that a single bout of aerobic exercise can significantly facilitate learning mechanisms within visual and motor domains and that these positive effects can persist for at least 30 minutes following exercise. This finding suggests that physical activity, at least of moderate intensity, might promote brain plasticity. By combining physical activity-induced plasticity with specific cognitive training-induced plasticity, we favour a gradual up-regulation of a functional network due to a steady increase in synaptic strength, promoting associative Hebbian-like plasticity.

  10. Microbial composition and ecological features of phototrophic biofilms proliferating in the Moidons Caves (France): investigation at the single-cell level.

    Science.gov (United States)

    Borderie, Fabien; Denis, Michel; Barani, Aude; Alaoui-Sossé, Badr; Aleya, Lotfi

    2016-06-01

    The authors investigated the microbial composition of phototrophic biofilms proliferating in a show cave using flow cytometry for the first time in such a context. Results are based on several biofilms sampled in the Moidons Caves (France) and concern both heterotrophic prokaryotes and autotrophic microorganisms. Heterotrophic microorganisms with low nucleic acid content were dominant in biofilms, as can be expected from the oligotrophic conditions prevailing within the cave. Analysis of the biofilm autotrophic components revealed the presence of several taxa, particularly the unicellular green algae Chlorella minutissima, specifically well adapted to this cave. Relationships between flow cytometry results and environmental variables determined in the cave were established and discussed so as to better understand biofilm proliferation processes in caves.

  11. Constant growth rate can be supported by decreasing energy flux and increasing aerobic glycolysis

    NARCIS (Netherlands)

    Slavov, Nikolai; Budnik, Bogdan A; Schwab, David; Airoldi, Edoardo M; van Oudenaarden, Alexander

    2014-01-01

    Fermenting glucose in the presence of enough oxygen to support respiration, known as aerobic glycolysis, is believed to maximize growth rate. We observed increasing aerobic glycolysis during exponential growth, suggesting additional physiological roles for aerobic glycolysis. We investigated such ro

  12. Aerobic Digestion. Student Manual. Biological Treatment Process Control.

    Science.gov (United States)

    Klopping, Paul H.

    This manual contains the textual material for a single-lesson unit on aerobic sludge digestion. Topic areas addressed include: (1) theory of aerobic digestion; (2) system components; (3) performance factors; (4) indicators of stable operation; and (5) operational problems and their solutions. A list of objectives, glossary of key terms, and…

  13. Longitudinal Predictors of Aerobic Performance in Adolescent Soccer Players

    NARCIS (Netherlands)

    Valente-dos-Santos, Joao; Coelho-e-Silva, Manuel J.; Duarte, Joao; Figueiredo, Antonio J.; Liparotti, Joao R.; Sherar, Lauren B.; Elferink-Gemser, Marije T.; Malina, Robert M.

    2012-01-01

    Background. The importance of aerobic performance in youth soccer is well established. The aim of the present study was to evaluate the contributions of chronological age (CA), skeletal age (SA), body size, and training to the longitudinal development of aerobic performance in youth male soccer play

  14. Aerobic training in persons who have recovered from juvenile dermatomyositis

    DEFF Research Database (Denmark)

    Riisager, M; Mathiesen, P R; Vissing, J

    2013-01-01

    A recent study has shown that 36 persons who had recovered from juvenile dermatomyositis (JDM) have on average an 18% decrease in maximal oxygen uptake. The objective of this study was to investigate the effect of a 12-week aerobic training program in this group, and assess whether aerobic training...

  15. Aerobic rice: crop performance and water use efficiency

    Directory of Open Access Journals (Sweden)

    Chiara Grassi

    2011-11-01

    Full Text Available Rice (Oryza sativa production largely depends on traditional flooded rice systems whose sustainability is threatened by a progressive decrease in water availability and a constant increase in rice demand due to strong demographic boom in world population. A newly developed water-saving rice system is aerobic rice in which rice grows in nonflooded and unsaturated soil. From 2001, at the International Rice Research Institute in the Philippines, this system has been monitored to identify potentially promising varieties of rice able to grow as an irrigated upland crop and quantify yield potential and water use efficiency. This study reports on the results of cultivating the upland rice variety Apo under different water conditions in 2004-2005 at the IRRI farm in both the dry and wet seasons. The water treatments considered were: aerobic and flooded conditions, alternated flooded and aerobic conditions and aerobic after fallow. Yield and water productivity were compared between aerobic and flooded treatment in both seasons, with the objective of analysing the differences between water treatments. In the experiment the effect of different nitrogen (N application is also considered. The results indicate that the aerobic rice yield was lower than rice production under flood treatment, confirming that observed over past years. Nevertheless, when the aerobic condition is alternated with the anaerobic condition, or a fallow period, the production under aerobic treatment provides good yields (respectively 4.2 and 4.4 ha-1. The fallow period was introduced to observe the response of rice grown under this management. Water productivity was higher in aerobic fields, especially after fallow (0.88 g kg-1. The nitrogen application induced an increase in yield and water productivity, partially compensating for the lack of water in aerobic fields.

  16. Aerobic biodegradation of precoagulated cheese whey wastewater.

    Science.gov (United States)

    Rivas, Javier; Prazeres, Ana R; Carvalho, Fatima

    2011-03-23

    Prior to the application of an aerobic biological process, cheese whey wastewater has been pretreated by means of a precipitation stage by adding either NaOH or CaOH2. Both precipitating agents reduce roughly 50% of the raw wastewater chemical oxygen demand (COD). The sludge generated in the prestage shows acceptable settling properties, although solids from the CaOH2-treated effluent are better separated from the liquid bulk than those formed in NaOH-processed wastewater. In both situations, the presedimentation stage renders a supernatant more prone to biodegradation than the untreated effluent. The previous statement is corroborated by the determination of some biological kinetic parameters. Under the operating conditions used in this work, sludge generation after the biological process is reduced to a minimum. The sludge generated shows good settling properties, especially for those experiments in which CaOH2 has previously been added.

  17. Aerobic growth at nanomolar oxygen concentrations

    DEFF Research Database (Denmark)

    Stolper, Daniel; Revsbech, Niels Peter; Canfield, Donald Eugene

    2010-01-01

    known. These capabilities also provide a framework for reconstructing a critical period in the history of life, because low, but not negligible, atmospheric oxygen levels could have persisted before the "Great Oxidation" of the Earth's surface about 2.3 to 2.4 billion years ago. Here, we show......Molecular oxygen (O2) is the second most abundant gas in the Earth's atmosphere, but in many natural environments, its concentration is reduced to low or even undetectable levels. Although low-oxygen-adapted organisms define the ecology of low-oxygen environments, their capabilities are not fully...... that Escherichia coli K-12, chosen for its well-understood biochemistry, rapid growth rate, and low-oxygen-affinity terminal oxidase, grows at oxygen levels of ≤ 3 nM, two to three orders of magnitude lower than previously observed for aerobes. Our study expands both the environmental range and temporal history...

  18. Aerobic growth at nanomolar oxygen concentrations

    DEFF Research Database (Denmark)

    Stolper, Daniel Aaron; Revsbech, Niels Peter; Canfield, Donald Eugene

    2010-01-01

    known. These capabilities also provide a framework for reconstructing a critical period in the history of life, because low, but not negligible, atmospheric oxygen levels could have persisted before the “Great Oxidation” of the Earth’s surface about 2.3 to 2.4 billion years ago. Here, we show......Molecular oxygen (O2) is the second most abundant gas in the Earth’s atmosphere, but in many natural environments, its concentration is reduced to low or even undetectable levels. Although low-oxygen-adapted organisms define the ecology of low-oxygen environments, their capabilities are not fully...... that Escherichia coli K-12, chosen for its well-understood biochemistry, rapid growth rate, and low-oxygen-affinity terminal oxidase, grows at oxygen levels of ≤ 3 nM, two to three orders of magnitude lower than previously observed for aerobes. Our study expands both the environmental range and temporal history...

  19. Functional microbiology of soda lakes.

    Science.gov (United States)

    Sorokin, Dimitry Y; Banciu, Horia L; Muyzer, Gerard

    2015-06-01

    Soda lakes represent unique permanently haloalkaline system. Despite the harsh conditions, they are inhabited by abundant, mostly prokaryotic, microbial communities. This review summarizes results of studies of main functional groups of the soda lake prokaryotes responsible for carbon, nitrogen and sulfur cycling, including oxygenic and anoxygenic phototrophs, aerobic chemolithotrophs, fermenting and respiring anaerobes. The main conclusion from this work is that the soda lakes are very different from other high-salt systems in respect to microbial richness and activity. The reason for this difference is determined by the major physico-chemical features of two dominant salts - NaCl in neutral saline systems and sodium carbonates in soda lakes, that are influencing the amount of energy required for osmotic adaptation.

  20. Development of Aerobic Fitness in Young Team Sport Athletes.

    Science.gov (United States)

    Harrison, Craig B; Gill, Nicholas D; Kinugasa, Taisuke; Kilding, Andrew E

    2015-07-01

    The importance of a high level of aerobic fitness for team sport players is well known. Previous research suggests that aerobic fitness can be effectively increased in adults using traditional aerobic conditioning methods, including high-intensity interval and moderate-intensity continuous training, or more recent game-based conditioning that involves movement and skill-specific tasks, e.g. small-sided games. However, aerobic fitness training for youth team sport players has received limited attention and is likely to differ from that for adults due to changes in maturation. Given young athletes experience different rates of maturation and technical skill development, the most appropriate aerobic fitness training modes and loading parameters are likely to be specific to the developmental stage of a player. Therefore, we analysed studies that investigated exercise protocols to enhance aerobic fitness in young athletes, relative to growth and maturation, to determine current best practice and limitations. Findings were subsequently used to guide an evidence-based model for aerobic fitness development. During the sampling stage (exploration of multiple sports), regular participation in moderate-intensity aerobic fitness training, integrated into sport-specific drills, activities and skill-based games, is recommended. During the specialisation stage (increased commitment to a chosen sport), high-intensity small-sided games should be prioritised to provide the simultaneous development of aerobic fitness and technical skills. Once players enter the investment stage (pursuit of proficiency in a chosen sport), a combination of small-sided games and high-intensity interval training is recommended.

  1. Heritability of aerobic power of individuals in northeast Brazil.

    Science.gov (United States)

    Alonso, L; Souza, Ec; Oliveira, Mv; do Nascimento, Lfe; Dantas, Pms

    2014-12-01

    The objective of this study was to evaluate the genetic and environmental contribution to variation in aerobic power in monozygotic (MZ) and dizygotic (DZ) twins. The sample consisted of 20 MZ individuals (12 females and 8 males) and 16 DZ individuals (12 females and 4 males), aged from 8 to 26 years, residents in Natal, Rio Grande do Norte. The twins were assessed by a multistage fitness test. The rate of heritability found for aerobic power was 77%. Based on the results, the estimated heritability was largely responsible for the differences in aerobic power. This implies that such measures are under strong genetic influence.

  2. Bacteriocin formation by dominant aerobic sporeformers isolated from traditional maari

    DEFF Research Database (Denmark)

    Kaboré, Donatien; Thorsen, Line; Nielsen, Dennis Sandris

    2012-01-01

    The antimicrobial activity of 8 Bacillus spp. and 2 Lysinibacillus spp. representing the predominant aerobic sporeformers during traditional maari fermentations, a traditional fermented baobab seeds product from Burkina Faso, was investigated. The antimicrobial activity was assessed against a total...

  3. Is aerobic workload positively related to ambulatory blood pressure?

    DEFF Research Database (Denmark)

    Korshøj, Mette; Clays, Els; Lidegaard, Mark;

    2016-01-01

    PURPOSE: Cardiovascular disease is prevalent among workers with high levels of occupational physical activity. The increased risk may be due to a high relative aerobic workload, possibly leading to increased blood pressure. However, studies investigating the relation between relative aerobic...... workload and ambulatory blood pressure (ABP) are lacking. The aim was to explore the relationship between objectively measured relative aerobic workload and ABP. METHODS: A total of 116 cleaners aged 18-65 years were included after informed consent was obtained. A portable device (Spacelabs 90217......) was mounted for 24-h measurements of ABP, and an Actiheart was mounted for 24-h heart rate measurements to calculate relative aerobic workload as percentage of relative heart rate reserve. A repeated-measure multi-adjusted mixed model was applied for analysis. RESULTS: A fully adjusted mixed model...

  4. Effect of an aerobic exercise intervention on cardiac autonomic regulation

    DEFF Research Database (Denmark)

    Hallman, David M; Holtermann, Andreas; Søgaard, Karen;

    2017-01-01

    OBJECTIVE: The aim of this randomized controlled trial (RCT) was to determine whether aerobic exercise during work hours affects cardiac autonomic regulation in cleaners characterized by high levels of occupational physical activity and poor cardiorespiratory fitness. METHOD: Eligible cleaners (n......=116) were randomized to an aerobic exercise group (n=59) or a reference group (n=57) with lectures. The intervention group received two 30-min sessions per week of supervised aerobic exercise over 4months. Diurnal measurements of heart rate variability (HRV) and physical activity (accelerometry) were...... tended to decrease in the exercise group compared with the reference group from baseline to follow-up, being significant for the HF spectral component (p=0.03). CONCLUSION: Among cleaners, a worksite aerobic exercise intervention improved cardiac autonomic regulation during work and leisure...

  5. Enhanced aerobic nitrifying granulation by static magnetic field.

    Science.gov (United States)

    Wang, Xin-Hua; Diao, Mu-He; Yang, Ying; Shi, Yi-Jing; Gao, Ming-Ming; Wang, Shu-Guang

    2012-04-01

    One of the main challenging issues for aerobic nitrifying granules in treating high strength ammonia wastewater is the long granulation time required for activated sludge to transform into aerobic granules. The present study provides a novel strategy for enhancing aerobic nitrifying granulation by applying an intensity of 48.0mT static magnetic field. The element analysis showed that the applied magnetic field could promote the accumulation of iron compounds in the sludge. And then the aggregation of iron decreased the full granulation time from 41 to 25days by enhancing the setting properties of granules and stimulating the secretion of extracellular polymeric substances (EPS). Long-term, cycle experiments and fluorescence in-situ hybridization (FISH) analysis proved that an intensity of 48.0mT magnetic field could enhance the activities and growth of nitrite-oxidizing bacteria (NOB). These findings suggest that magnetic field is helpful and reliable for accelerating the aerobic nitrifying granulation.

  6. Isolation of aerobic bacteria from ticks infested sheep in Iraq

    Directory of Open Access Journals (Sweden)

    Waleed Ibrahem Jalil

    2016-01-01

    Conclusions: The high isolation rate of aerobic pathogens from ticks might reflect the active contribution of this arthropod in environmental contamination and increase the probability of transmitting bacterial pathogens to their hosts.

  7. THE RELATIONSHIP OF CHOREOGRAPHY PREPARATION AND ARTISTRY IN AEROBIC GYMNASTICS

    Directory of Open Access Journals (Sweden)

    I. V. Sokolova

    2015-02-01

    Full Text Available Examines the impact choreography training in sports aerobics on artistic skills.Objective to investigate whether the use of funds choreo-graphy in training athletes involved in sports aerobics, to find the relationship between choreographic training and asses-sment for artistry.Method or methodology of work methods of studying the theoretical ski works of scientific content, analysis and processing of scientific texts.The results revealed the relationship between estimates for artistry and means-you dance training in sports aerobics. The scope of the results, the materials may be used by coaches in sports aerobics, for further research on the problem of constructing workout.

  8. Sequential anaerobic-aerobic treatment for domestic wastewater - A review

    NARCIS (Netherlands)

    Kassab, G.; Halalsheh, M.; Klapwijk, A.; Fayyad, M.; Lier, van J.B.

    2010-01-01

    Introduction, consolidation and even standardization of expensive conventional aerobic systems for domestic wastewater treatment imposed significant financial constraints on the expansion of sanitary services including treatment in developing countries. A viable alternative is the sequential anaerob

  9. Aerobic Exercise: Top 10 Reasons to Get Physical

    Science.gov (United States)

    ... plaques in your arteries. Boost your mood Aerobic exercise may ease the gloominess of depression, reduce the tension associated with anxiety and promote relaxation. Stay active and independent as ...

  10. Nitrifying and denitrifying bacteria in aerobic granules formed in sequencing batch airlift reactors

    Institute of Scientific and Technical Information of China (English)

    WANG Fang; YANG Fenglin; QI Aijiu

    2007-01-01

    The purpose of this study was to investigate nitrifying bacteria and denitrifying bacteria isolated from aerobic granules.Aerobic granules were formed in an internal-circulate sequencing batch airlift reactor(SBAR)and biodegradation of NH3 -N was analyzed in the reactor.Bacteria were isolated and determined from aerobic granules using selected media.The growth properties and morphology of bacteria colonies were observed by controlling aerobic or anaerobic conditions in the culture medium.It was found that bacteria in aerobic granules were diverse and some of them were facultative aerobes.The diversity of bacteria in aerobic granules was a premise of simultaneous nitrification and denitrification.

  11. Aerobic training and postexercise protein in facioscapulohumeral muscular dystrophy

    DEFF Research Database (Denmark)

    Andersen, Grete; Prahm, Kira P; Dahlqvist, Julia R;

    2015-01-01

    OBJECTIVE: To investigate the effect of regular aerobic training and postexercise protein-carbohydrate supplementation in patients with facioscapulohumeral muscular dystrophy (FSHD). METHODS: In this randomized, double-blind, placebo-controlled parallel study, we randomized untrained men (n = 21...... not add any further improvement to training effects alone. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that regular aerobic training with or without postexercise protein-carbohydrate supplementation improves fitness and workload in patients with FSHD....

  12. Water Aerobics as a Form of Health Activities

    Directory of Open Access Journals (Sweden)

    Anna S. Batrak

    2013-09-01

    Full Text Available The offered literature review considers water aerobics as a form of health activities. Water aerobics is wide spread and popular, especially among women, because it is also the form of adaptive and health activities. It enlarges general physiological effect of physical exercises on the human body. Regular exercises improve physical fitness and physical development, health, mood, sleep, intensify activities and working efficiency.

  13. Membrane-bound respiratory chain of Pseudomonas aeruginosa grown aerobically.

    OpenAIRE

    Matsushita, K.; Yamada, M.; Shinagawa, E; Adachi, O; Ameyama, M

    1980-01-01

    The electron transport chain of the gram-negative bacterium Pseudomonas aeruginosa, grown aerobically, contained a number of primary dehydrogenases and respiratory components (soluble flavin, bound flavin, coenzyme Q9, heme b, heme c, and cytochrome o) in membrane particles of the organism. Cytochrome o, about 50% of the b-type cytochrome, seemed to function as a terminal oxidase in the respiratory chain. The electron transport chain of P. aeruginosa grown aerobically was suggested to be line...

  14. Aerobic training in children with cerebral palsy.

    Science.gov (United States)

    Nsenga, A L; Shephard, R J; Ahmaidi, S; Ahmadi, S

    2013-06-01

    Rehabilitation is a major goal for children with cerebral palsy, although the potential to enhance cardio-respiratory fitness in such individuals remains unclear. This study thus compared current cardio-respiratory status between children with cerebral palsy and able-bodied children, and examined the ability to enhance the cardio-respiratory fitness of children with cerebral palsy by cycle ergometer training. 10 children with cerebral palsy (Gross Motor Function Classification System levels I and II) participated in thrice-weekly 30 min cycle ergometer training sessions for 8 weeks (mean age: 14.2±1.9 yrs). 10 additional subjects with cerebral palsy (mean age: 14.2±1.8 yrs) and 10 able-bodied subjects (mean age: 14.1±2.1 yrs) served as controls, undertaking no training. All subjects undertook a progressive cycle ergometer test of cardio-respiratory fitness at the beginning and end of the 8-week period. Cardio-respiratory parameters [oxygen intake V˙O2), ventilation V ˙ E) and heart rate (HR)] during testing were measured by Cosmed K4 b gas analyzer. The children with cerebral palsy who engaged in aerobic training improved their peak oxygen consumption, heart rate and ventilation significantly (pchildren with cerebral palsy can benefit significantly from cardio-respiratory training, and such training should be included in rehabilitation programs.

  15. Personality, metabolic rate and aerobic capacity.

    Directory of Open Access Journals (Sweden)

    Antonio Terracciano

    Full Text Available Personality traits and cardiorespiratory fitness in older adults are reliable predictors of health and longevity. We examined the association between personality traits and energy expenditure at rest (basal metabolic rate and during normal and maximal sustained walking. Personality traits and oxygen (VO(2 consumption were assessed in 642 participants from the Baltimore Longitudinal Study of Aging. Results indicate that personality traits were mostly unrelated to resting metabolic rate and energy expenditure at normal walking pace. However, those who scored lower on neuroticism (r = -0.12 and higher on extraversion (r = 0.11, openness (r = 0.13, and conscientiousness (r = 0.09 had significantly higher energy expenditure at peak walking pace. In addition to greater aerobic capacity, individuals with a more resilient personality profile walked faster and were more efficient in that they required less energy per meter walked. The associations between personality and energy expenditure were not moderated by age or sex, but were in part explained by the proportion of fat mass. In conclusion, differences in personality may matter the most during more challenging activities that require cardiorespiratory fitness. These findings suggest potential pathways that link personality to health outcomes, such as obesity and longevity.

  16. Aerobic nitroreduction of dehydrochloramphenicol by bone marrow.

    Science.gov (United States)

    Isildar, M; Abou-Khalil, W H; Jimenez, J J; Abou-Khalil, S; Yunis, A A

    1988-06-30

    It has been previously demonstrated that dehydrochloramphenicol (DH-CAP), a bacterial metabolite of chloramphenicol, induces DNA single strand breaks in intact cells and is profoundly more cytotoxic than chloramphenicol (CAP). In view of previous observations relating genotoxicity of nitrocompounds to their nitroreduction by the target tissue, we studied the nitroreduction of DH-CAP by human and rabbit bone marrow. Nitroreduction by tissue homogenates was determined by the Bratton Marshall colorimetric assay and by high-performance liquid chromatography (HPLC). Nitroreduction of DH-CAP by bone marrow cell homogenates was observed under aerobic conditions and the reduction was both cell concentration- and time-dependent. The formation of the amino product aminodehydrochloramphenicol was confirmed by HPLC. Reduction by other tissues including human liver, Raji cells, and HL-60 tumors was also observed. These results suggest that genotoxicity of DH-CAP may be related to its nitroreduction by the target tissue with in situ production of toxic intermediates. Together with previous studies, these observations lend support to the thesis that the p-NO2 group may be the structural feature underlying aplastic anemia from CAP.

  17. Dancing the aerobics ''hearing loss'' choreography

    Science.gov (United States)

    Pinto, Beatriz M.; Carvalho, Antonio P. O.; Gallagher, Sergio

    2002-11-01

    This paper presents an overview of gymnasiums' acoustic problems when used for aerobics exercises classes (and similar) with loud noise levels of amplified music. This type of gymnasium is usually a highly reverberant space, which is a consequence of a large volume surrounded by hard surfaces. A sample of five schools in Portugal was chosen for this survey. Noise levels in each room were measured using a precision sound level meter, and analyzed to calculate the standardized daily personal noise exposure levels (LEP,d). LEP,d values from 79 to 91 dB(A) were found to be typical values in this type of room, inducing a health risk for its occupants. The reverberation time (RT) values were also measured and compared with some European legal requirements (Portugal, France, and Belgium) for nearly similar situations. RT values (1 kHz) from 0.9 s to 2.8 s were found. These reverberation time values clearly differentiate between good and acoustically inadequate rooms. Some noise level and RT limits for this type of environment are given and suggestions for the improvement of the acoustical environment are shown. Significant reductions in reverberation time values and noise levels can be obtained by simple measures.

  18. Energy efficient aerobic treatment of forest industry wastewaters; Energieffektiv aerob rening av skogsindustriella avloppsvatten

    Energy Technology Data Exchange (ETDEWEB)

    Sandberg, Maria; From-Aldaron, Mattias

    2011-01-15

    There is great potential to reduce energy requirements in aerobic biological purification if the oxygen demand can be reduced and oxygen delivery, when process water is aerated, is made more efficient. A model was developed to estimate the possible reduction in oxygen demand. Model variables were COD reduction, sludge withdrawal, oxygen, and alpha-value. Attempts made in an aerator in the lab-scale process shows that water content strongly affects oxygen transport and alpha-value. Surface active extract substances such as fatty acids and resin acids have greatest significance. The effect increases with the concentration of extract substances and decreases with added sodium chloride content

  19. Forced Aerobic Exercise Preceding Task Practice Improves Motor Recovery Poststroke

    Science.gov (United States)

    Rosenfeldt, Anson B.; Dey, Tanujit; Alberts, Jay L.

    2017-01-01

    OBJECTIVE. To understand how two types of aerobic exercise affect upper-extremity motor recovery post-stroke. Our aims were to (1) evaluate the feasibility of having people who had a stroke complete an aerobic exercise intervention and (2) determine whether forced or voluntary exercise differentially facilitates upper-extremity recovery when paired with task practice. METHOD. Seventeen participants with chronic stroke completed twenty-four 90-min sessions over 8 wk. Aerobic exercise was immediately followed by task practice. Participants were randomized to forced or voluntary aerobic exercise groups or to task practice only. RESULTS. Improvement on the Fugl-Meyer Assessment exceeded the minimal clinically important difference: 12.3, 4.8, and 4.4 for the forced exercise, voluntary exercise, and repetitive task practice–only groups, respectively. Only the forced exercise group exhibited a statistically significant improvement. CONCLUSION. People with chronic stroke can safely complete intensive aerobic exercise. Forced aerobic exercise may be optimal in facilitating motor recovery associated with task practice. PMID:28218596

  20. Formation, characterization and mathematical modeling of the aerobic granular sludge

    Energy Technology Data Exchange (ETDEWEB)

    Ni, Bing-Jie [Queensland Univ., Brisbane, QLD (Australia). Advanced Water Management Centre

    2013-07-01

    Reports on successful aerobic granulation of sludge in pilot-scale reactor for treatment of low-strength municipal wastewater and identifies the key factors responsible for this process. Develops comprehensive models for sludge granulation, microbial interactions and microbial products formation to provide insights into the dynamics of all the soluble and solid components in aerobic granular sludge system. Demonstrates accelerated start-up and optimization of the anaerobic ammonia oxidation process by seeding the reactor with aerobic granules. Aerobic granular sludge technology will play an important role as an innovative technology alternative to the present activated sludge process in industrial and municipal wastewater treatment in the near future. Intended to fill the gaps in the studies of aerobic granular sludge, this thesis comprehensively investigates the formation, characterization and mathematical modeling of aerobic granular sludge, through integrating the process engineering tools and advanced molecular microbiology. The research results of this thesis contributed significantly to the advance of understanding and optimization of the bacterial granulation processes, the next generation of technology for cost-effective biological wastewater treatment.

  1. Comparison of Combined Aerobic and High-Force Eccentric Resistance Exercise With Aerobic Exercise Only for People With Type 2 Diabetes Mellitus

    OpenAIRE

    Marcus, Robin L.; Smith, Sheldon; Morrell, Glen; Addison, Odessa; Dibble, Leland E.; Wahoff-Stice, Donna; LaStayo, Paul C.

    2008-01-01

    Background and Purpose: The purpose of this study was to compare the outcomes between a diabetes exercise training program using combined aerobic and high-force eccentric resistance exercise and a program of aerobic exercise only.

  2. Phototrophic cultivation of a thermo-tolerant Desmodesmus sp. for lutein production: effects of nitrate concentration, light intensity and fed-batch operation.

    Science.gov (United States)

    Xie, Youping; Ho, Shih-Hsin; Chen, Ching-Nen Nathan; Chen, Chun-Yen; Ng, I-Son; Jing, Ke-Ju; Chang, Jo-Shu; Lu, Yinghua

    2013-09-01

    Four indigenous thermo-tolerant Desmodesmus sp. strains were examined for their ability to produce lutein. Among them, Desmodesmus sp. F51 was the best strain for this purpose. The medium composition, nitrate concentration and light intensity were manipulated to improve the phototrophic growth and lutein production of Desmodesmus sp. F51. It was found that a nitrogen-sufficient condition was required for lutein accumulation, while a high light intensity enhanced cell growth but caused a decrease in the lutein content. The best cell growth and lutein production occurred when the light intensity and initial nitrate concentration were 600 μmol/m(2)/s and 8.8 mM, respectively. The fed-batch cultivation strategy was shown to further improve lutein production. The highest lutein productivity (3.56±0.10 mg/L/d) and content (5.05±0.20 mg/g) were obtained when pulse-feeding of 2.2 mM nitrate was employed. This study demonstrated the potential of using Desmodesmus sp. F51 as a lutein producer in practical applications.

  3. Chlorobaculum tepidum Modulates Amino Acid Composition in Response to Energy Availability, as Revealed by a Systematic Exploration of the Energy Landscape of Phototrophic Sulfur Oxidation.

    Science.gov (United States)

    Levy, Amalie T; Lee, Kelvin H; Hanson, Thomas E

    2016-11-01

    Microbial sulfur metabolism, particularly the formation and consumption of insoluble elemental sulfur (S(0)), is an important biogeochemical engine that has been harnessed for applications ranging from bioleaching and biomining to remediation of waste streams. Chlorobaculum tepidum, a low-light-adapted photoautolithotrophic sulfur-oxidizing bacterium, oxidizes multiple sulfur species and displays a preference for more reduced electron donors: sulfide > S(0) > thiosulfate. To understand this preference in the context of light energy availability, an "energy landscape" of phototrophic sulfur oxidation was constructed by varying electron donor identity, light flux, and culture duration. Biomass and cellular parameters of C. tepidum cultures grown across this landscape were analyzed. From these data, a correction factor for colorimetric protein assays was developed, enabling more accurate biomass measurements for C. tepidum, as well as other organisms. C. tepidum's bulk amino acid composition correlated with energy landscape parameters, including a tendency toward less energetically expensive amino acids under reduced light flux. This correlation, paired with an observation of increased cell size and storage carbon production under electron-rich growth conditions, suggests that C. tepidum has evolved to cope with changing energy availability by tuning its proteome for energetic efficiency and storing compounds for leaner times.

  4. Formation and functions of aerobic microbial granula; Entstehung und Funktionen aerober mikrobieller Granula

    Energy Technology Data Exchange (ETDEWEB)

    Etterer, T.; Wilderer, P.A. [Technische Univ. Muenchen, Garching (Germany). Lehrstuhl und Pruefamt fuer Wasserguete- und Abfallwirtschaft

    1999-07-01

    The present project investigates the phenomenon of the formation of aerobic microbial granula and their properties. To generate granula, sequencing batch reactors fed in batches were used. As shown by microbiological assays, fungi played an above-average role in granula formation and build-up. In first degradation experiments, furthermore, chemical oxygen demand (COD) could be reduced by over 90 %. The determination yielded comparable values to activated sludge, standing on average at 1.044g/ml. (orig.) [German] Im Rahmen des hier vorgestellten Projekts wurde das Phaenomen der Bildung aerober mikrobieller Granula sowie deren Eigenschaften untersucht. Zur Erzeugung von Granula wurden schubweise beschickte Reaktoren, sogenannte Sequencing-Batch-Reaktoren (SBR) verwendet. Wie mikrobiologische Untersuchungen zeigten spielen Pilze bei der Entstehung und beim Aufbau eine ueberdurchschnittliche Rolle. Des weiteren konnte in ersten Abbauversuchen der chemische Sauerstoff-Bedarf (CSB) um ueber 90% gesenkt werden. Die Dichtebestimmung ergab vergleichbare Werte zu Belebtschlamm und zwar im Durchschnitt 1,044 g/ml. (orig.)

  5. Enhanced selection of micro-aerobic pentachlorophenol degrading granular sludge

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Yuancai, E-mail: donkey1204@hotmail.com [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Chen, Yuancai, E-mail: chenyc@scut.edu.cn [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Song, Wenzhe, E-mail: songwenzhe007@126.com [Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Hu, Yongyou, E-mail: ppyyhu@scut.edu.cn [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China)

    2014-09-15

    Graphical abstract: In this work, an aerobic column reactor was placed before the USB to maintain micro-oxygen condition in the reactor and the micro-aerobic pentachlorophenol (PCP) degrading granular sludge under oxygen-limited conditions (0.1–0.2 mg L{sup −1}) was successfully obtained. PCP degradation by the micro-aerobic system was studied and the variance of microbial community was also discussed by using PCR-DGGE analysis. - Highlights: • Micro-aerobic granular sludge was cultivated in column-type combined reactors. • PCP biodegradation, VFA accumulation and biogas production were studied. • The function of Methanogenic archaeon in the system was investigated. • Fluctuation and diversity of microbial community were discussed by DGGE analysis. • The dominated microorganisms were identified by 16S rDNA sequences. - Abstract: Column-type combined reactors were designed to cultivate micro-aerobic pentachlorophenol (PCP) degrading granular sludge under oxygen-limited conditions (0.1–0.2 mg L{sup −1}) over 39-day experimental period. Micro-aerobic granular had both anaerobic activity (SMA: 2.34 mMCH{sub 4}/h g VSS) and aerobic activity (SOUR: 2.21 mMO{sub 2}/h g VSS). Metabolite analysis results revealed that PCP was sequentially dechlorinated to TCP, DCP, and eventually to MCP. Methanogens were not directly involved in the dechlorination of PCP, but might played a vital role in stabilizing the overall structure of the granule sludge. For Eubacteria, the Shannon Index (2.09 in inoculated granular sludge) increased both in micro-aerobic granular sludge (2.61) and PCP-degradation granular sludge (2.55). However, for Archaea, it decreased from 2.53 to 1.85 and 1.84, respectively. Although the Shannon Index demonstrated slight difference between micro-aerobic granular sludge and PCP-degradation granular sludge, the Principal Component Analysis (PCA) indicated obvious variance of the microbial composition, revealing significant effect of micro-aerobic

  6. Denitrification characteristics of a marine origin psychrophilic aerobic denitrifying bacterium

    Institute of Scientific and Technical Information of China (English)

    Haiyan Zheng; Ying Liu; Guangdong Sun; Xiyan Gao; Qingling Zhang; Zhipei Liu

    2011-01-01

    A psychrophilic aerobic denitrifying bacterium,strain S1-1,was isolated from a biological aerated filter conducted for treatment of recirculating water in a marine aquaculture system.Strain S1-1 was preliminarily identified as Psychrobacter sp.based on the analysis of its 16S rRNA gene sequence,which showed 100% sequence similarity to that of Psychrobacter sp.TSBY-70.Strain S 1-1 grew well either in high nitrate or high nitrite conditions with a removal of 100% nitrate or 63.50% nitrite,and the total nitrogen removal rates could reach to 46.48% and 31.89%,respectively.The results indicated that nitrate was mainly reduced in its logarithmic growth phase with a very low leve 1 accumulation of nitrite,suggesting that the aerobic denitrification process of strain S l-1 occurred mainly in this phase.The GC-MS results showed that N2O was formed as the major intermediate during the aerobic denitrifying process of strain S1-1.Finally,factors affecting the growth of strain Sl-1 and its aerobic denitrifying ability were also investigated.Results showed that the optimum aerobic denitrification conditions for strain S1-1 were sodium succinate as carbon source,C/N ratio15,salinity 10 g/L NaCl,incubation temperature 20℃ and initial pH 6.5.

  7. Effects of 12 weeks of aerobic training on autonomic modulation, mucociliary clearance, and aerobic parameters in patients with COPD

    Science.gov (United States)

    Leite, Marceli Rocha; Ramos, Ercy Mara Cipulo; Kalva-Filho, Carlos Augusto; Freire, Ana Paula Coelho Figueira; de Alencar Silva, Bruna Spolador; Nicolino, Juliana; de Toledo-Arruda, Alessandra Choqueta; Papoti, Marcelo; Vanderlei, Luiz Carlos Marques; Ramos, Dionei

    2015-01-01

    Introduction Patients with chronic obstructive pulmonary disease (COPD) exhibit aerobic function, autonomic nervous system, and mucociliary clearance alterations. These parameters can be attenuated by aerobic training, which can be applied with continuous or interval efforts. However, the possible effects of aerobic training, using progressively both continuous and interval sessions (ie, linear periodization), require further investigation. Aim To analyze the effects of 12-week aerobic training using continuous and interval sessions on autonomic modulation, mucociliary clearance, and aerobic function in patients with COPD. Methods Sixteen patients with COPD were divided into an aerobic (continuous and interval) training group (AT) (n=10) and a control group (CG) (n=6). An incremental test (initial speed of 2.0 km·h−1, constant slope of 3%, and increments of 0.5 km·h−1 every 2 minutes) was performed. The training group underwent training for 4 weeks at 60% of the peak velocity reached in the incremental test (vVO2peak) (50 minutes of continuous effort), followed by 4 weeks of sessions at 75% of vVO2peak (30 minutes of continuous effort), and 4 weeks of interval training (5×3-minute effort at vVO2peak, separated by 1 minute of passive recovery). Intensities were adjusted through an incremental test performed at the end of each period. Results The AT presented an increase in the high frequency index (ms2) (P=0.04), peak oxygen uptake (VO2peak) (P=0.01), vVO2peak (P=0.04), and anaerobic threshold (P=0.02). No significant changes were observed in the CG (P>0.21) group. Neither of the groups presented changes in mucociliary clearance after 12 weeks (AT: P=0.94 and CG: P=0.69). Conclusion Twelve weeks of aerobic training (continuous and interval sessions) positively influenced the autonomic modulation and aerobic parameters in patients with COPD. However, mucociliary clearance was not affected by aerobic training. PMID:26648712

  8. Aerobic exercise reduces biomarkers related to cardiovascular risk among cleaners

    DEFF Research Database (Denmark)

    Korshøj, Mette; Ravn, Marie Højbjerg; Holtermann, Andreas

    2016-01-01

    PURPOSE: Blue-collar workers have an increased risk of cardiovascular disease. Accordingly, elevated levels of biomarkers related to risk of cardiovascular disease, such as high-sensitive C-reactive protein, have been observed among blue-collar workers. The objective was to examine whether...... an aerobic exercise worksite intervention changes the level of inflammation biomarkers among cleaners. METHODS: The design was a cluster-randomized controlled trial with 4-month worksite intervention. Before the 116 cleaners aged 18-65 years were randomized, they signed an informed consent form....... The reference group (n = 59) received lectures, and the aerobic exercise group (n = 57) performed worksite aerobic exercise (30 min twice a week). Levels of biomarkers (high-sensitive C-reactive protein, fibrinogen, cholesterol, low- and high-density lipoprotein cholesterol and triglyceride) were collected...

  9. Virulence factors enhance Citrobacter rodentium expansion through aerobic respiration.

    Science.gov (United States)

    Lopez, Christopher A; Miller, Brittany M; Rivera-Chávez, Fabian; Velazquez, Eric M; Byndloss, Mariana X; Chávez-Arroyo, Alfredo; Lokken, Kristen L; Tsolis, Renée M; Winter, Sebastian E; Bäumler, Andreas J

    2016-09-16

    Citrobacter rodentium uses a type III secretion system (T3SS) to induce colonic crypt hyperplasia in mice, thereby gaining an edge during its competition with the gut microbiota through an unknown mechanism. Here, we show that by triggering colonic crypt hyperplasia, the C. rodentium T3SS induced an excessive expansion of undifferentiated Ki67-positive epithelial cells, which increased oxygenation of the mucosal surface and drove an aerobic C. rodentium expansion in the colon. Treatment of mice with the γ-secretase inhibitor dibenzazepine to diminish Notch-driven colonic crypt hyperplasia curtailed the fitness advantage conferred by aerobic respiration during C. rodentium infection. We conclude that C. rodentium uses its T3SS to induce histopathological lesions that generate an intestinal microenvironment in which growth of the pathogen is fueled by aerobic respiration.

  10. Isolation and denitrification characteristic of an aerobic denitrifier

    Institute of Scientific and Technical Information of China (English)

    ZHOU Dan-dan; MA Fang; WANG Hong-yu; DONG Shuang-shi; WANG Ai-jie

    2006-01-01

    Aerobic denitrifiers were enriched by activated sludge cultivation method. By this way, 105 strains were isolated from the activated sludge and 25 strains were confirmed to be capable of obtaining energy by deoxidization of nitrate to nitrogen gas under aerobic condition. The characteristic of one denitrifier, Pseudomonas chloritidismutans strain, was particularly studied due to its higher nitrogen removal rate. It was found that Pseudomonas chloritidismutans can use nitrite, nitrate and oxygen for aerobic respiration in liquid medium, and the pH increased and ORP decreased by activated denitrifier. When they used nitrite or nitrate for respiration, nitrogen removal effect was high and nitrite could be reduced more efficiently than nitrate. Denitrification process was accomplished faster when both nitrite and nitrate existed in the medium compared to each of which existed alone. Particularly, at denitrifying activity, the nitrogen removal rate of strain was not affected by the DO concentration in the culture media.

  11. Evaluation of Biodegradability of Waste Before and After Aerobic Treatment

    Directory of Open Access Journals (Sweden)

    Suchowska-Kisielewicz Monika

    2014-12-01

    Full Text Available An important advantage of use of an aerobic biostabilization of waste prior to its disposal is that it intensifies the decomposition of the organic fraction of waste into the form which is easily assimilable for methanogenic microorganisms involved in anaerobic decomposition of waste in the landfill. In this article it is presented the influence of aerobic pre-treatment of waste as well as leachate recirculation on susceptibility to biodegradation of waste in anaerobic laboratory reactors. The research has shown that in the reactor with aerobically treated waste stabilized with recilculation conversion of the organic carbon into the methane is about 45% higher than in the reactor with untreated waste stabilized without recirculation.

  12. Assessment of Aerobic Exercise Adverse Effects during COPD Exacerbation Hospitalization

    Directory of Open Access Journals (Sweden)

    Caroline Knaut

    2017-01-01

    Full Text Available Introduction. Aerobic exercise performed after hospital discharge for exacerbated COPD patients is already recommended to improve respiratory and skeletal muscle strength, increase tolerance to activity, and reduce the sensation of dyspnea. Previous studies have shown that anaerobic activity can clinically benefit patients hospitalized with exacerbated COPD. However, there is little information on the feasibility and safety of aerobic physical activity performed by patients with exacerbated COPD during hospitalization. Objective. To evaluate the effects of aerobic exercise on vital signs in hospitalized patients with exacerbated COPD. Patients and Methods. Eleven COPD patients (63% female, FEV1: 34.2 ± 13.9% and age: 65 ± 11 years agreed to participate. Aerobic exercise was initiated 72 hours after admission on a treadmill; speed was obtained from the distance covered in a 6-minute walk test (6MWT. Vital signs were assessed before and after exercise. Results. During the activity systolic blood pressure increased from 125.2 ± 13.6 to 135.8 ± 15.0 mmHg (p=0.004 and respiratory rate from 20.9 ± 4.4 to 24.2 ± 4.5 rpm (p=0.008 and pulse oximetry (SpO2 decreased from 93.8 ± 2.3 to 88.5 ± 5.7% (p<0.001. Aerobic activity was considered intense, heart rate ranged from 99.2 ± 11.5 to 119.1 ± 11.1 bpm at the end of exercise (p=0.092, and patients reached on average 76% of maximum heart rate. Conclusion. Aerobic exercise conducted after 72 hours of hospitalization in patients with exacerbated COPD appears to be safe.

  13. Exercise intensity during Zumba fitness and Tae-bo aerobics

    OpenAIRE

    Hižnayová, Kristína

    2013-01-01

    This study analyzed and compared the exercise intensity in Zumba fitness and Tae-bo aerobics. Object of the research was monitoring of the heart rate and energy consumption in kcal during exercise unit, by using Heart Rate Monitor Suunto Memory Belt. All measurements were attended by randomly selected 11 women. The data we collected during the six units of the Zumba fitness and six units of the Tae-bo aerobics . Obtained data of the heart rate were evaluated in three main parts of workout: af...

  14. Copper intoxication inhibits aerobic nucleotide synthesis in Streptococcus pneumoniae

    Science.gov (United States)

    Johnson, Michael D. L.; Kehl-Fie, Thomas E.; Rosch, Jason W.

    2015-01-01

    Copper is universally toxic in excess, a feature exploited by the human immune system to facilitate bacterial clearance. The mechanism of copper intoxication remains unknown for many bacterial species. Here, we demonstrate that copper toxicity in Streptococcus pneumoniae is independent from oxidative stress but, rather, is the result of copper inhibiting the aerobic dNTP biosynthetic pathway. Furthermore, we show that copper-intoxicated S. pneumoniae is rescued by manganese, which is an essential metal in the aerobic nucleotide synthesis pathway. These data provide insight into new targets to enhance copper-mediated toxicity during bacterial clearance. PMID:25730343

  15. Cardiorespiratory fitness of asthmatic children and validation of predicted aerobic capacity

    DEFF Research Database (Denmark)

    Lochte, Lene; Angermann, Marie; Larsson, Benny

    2009-01-01

    INTRODUCTION: Predicted aerobic capacity (PAC) was estimated by submaximal exercise test and compared with monitored aerobic capacity (MAC) measured by laboratory conditions [maximal oxygen uptake (VO(2peak))] in 18 children and adolescents, 10 asthmatics and 8 matched controls. Objectives...

  16. Lung volumes related to physical activity, physical fitness, aerobic capacity and body mass index in students

    Directory of Open Access Journals (Sweden)

    Mihailova A.

    2016-01-01

    Reduced lung volumes were associated with lower aerobic fitness, lower physical fitness and lower amount of weekly physical activity. Healthier body mass index was associated with higher aerobic fitness (relative VO2max in both female and male.

  17. Treatment of anthraquinone dye wastewater by hydrolytic acidification-aerobic process

    Institute of Scientific and Technical Information of China (English)

    YANG Jian; WU Min; Li Dan

    2004-01-01

    Experiment on microbial degradation with two kinds of biological process, hydrolytic acidification-aerobic process and aerobic process was conducted to treat the anthraquinone dye wastewater with CODCr concentration of 400 mg/L and chroma 800. The experimental result demonstrated that the hydrolytic-aerobic process could raise the biodegradability of anthraquinone dye wastewater effectively. The effluent CODCr can reach 120-170 mg/L and chroma 150 which is superior to that from simple aerobic process.

  18. Anaerobes unleashed: Aerobic fuel cells of Geobacter sulfurreducens

    Science.gov (United States)

    Nevin, Kelly P.; Zhang, Pei; Franks, Ashley E.; Woodard, Trevor L.; Lovley, Derek R.

    One of the limitations of power generation with microbial fuel cells is that the anode must typically be maintained under anaerobic conditions. When oxygen is present in the anode chamber microorganisms oxidize the fuel with the reduction of oxygen rather than electron transfer to the anode. A system in which fuel is provided from within a graphite anode and diffuses out to the outer surface of the anode was designed to overcome these limitations. A biofilm of Geobacter sulfurreducens strain KN400, pregrown on the surface of a graphite electrode in a traditional two-chambered system with an anaerobic anode chamber and acetate as an external fuel source, produced current just as well under aerobic conditions when acetate was provided via diffusion from an internal concentrated acetate solution. No acetate was detectable in the external medium. In contrast, aerobic systems in which acetate was provided in the external medium completely failed within 48 h. Internally fed anodes colonized by a strain of KN400 adapted to grow at marine salinities produced current in aerobic seawater as well as an anaerobic anode system. The ability to generate current with an anode under aerobic conditions increases the potential applications and design options for microbial fuel cells.

  19. Tumor vessel normalization after aerobic exercise enhances chemotherapeutic efficacy.

    Science.gov (United States)

    Schadler, Keri L; Thomas, Nicholas J; Galie, Peter A; Bhang, Dong Ha; Roby, Kerry C; Addai, Prince; Till, Jacob E; Sturgeon, Kathleen; Zaslavsky, Alexander; Chen, Christopher S; Ryeom, Sandra

    2016-10-04

    Targeted therapies aimed at tumor vasculature are utilized in combination with chemotherapy to improve drug delivery and efficacy after tumor vascular normalization. Tumor vessels are highly disorganized with disrupted blood flow impeding drug delivery to cancer cells. Although pharmacologic anti-angiogenic therapy can remodel and normalize tumor vessels, there is a limited window of efficacy and these drugs are associated with severe side effects necessitating alternatives for vascular normalization. Recently, moderate aerobic exercise has been shown to induce vascular normalization in mouse models. Here, we provide a mechanistic explanation for the tumor vascular normalization induced by exercise. Shear stress, the mechanical stimuli exerted on endothelial cells by blood flow, modulates vascular integrity. Increasing vascular shear stress through aerobic exercise can alter and remodel blood vessels in normal tissues. Our data in mouse models indicate that activation of calcineurin-NFAT-TSP1 signaling in endothelial cells plays a critical role in exercise-induced shear stress mediated tumor vessel remodeling. We show that moderate aerobic exercise with chemotherapy caused a significantly greater decrease in tumor growth than chemotherapy alone through improved chemotherapy delivery after tumor vascular normalization. Our work suggests that the vascular normalizing effects of aerobic exercise can be an effective chemotherapy adjuvant.

  20. Aerobic Jogging Instruction for Students in Grades 7-12.

    Science.gov (United States)

    Nebraska State Dept. of Education, Lincoln.

    Jogging, a form of aerobic exercise, is the act of running at a slow trot. This guide describes an instructional program for high school students to jog progressively longer distances. The emphasis is on participation and gradual improvement. Training principles, teaching methods, common jogging problems, and safety precautions are listed to aid…

  1. Aerobic Oxidation of Methyl Vinyl Ketone in Supercritical Carbon Dioxide

    Institute of Scientific and Technical Information of China (English)

    OUYANG,Xiao-Yue(欧阳小月); JIANG,Huan-Feng(江焕峰); CHENG,Jin-Sheng(程金生); ZHANG,Qun-Jian(张群健)

    2002-01-01

    Aerobic oxidation of methyl vinyl ketone to acetal in supercritical carbon dioxide are achieved in high conversion and high selectivity when oxygen pressure reaches 0.5MPa. The effects of cocatalysts,additive, pressure and temperature of the reaction are studied in detail.

  2. Aerobic Capacity and Anaerobic Power Levels of the University Students

    Science.gov (United States)

    Taskin, Cengiz

    2016-01-01

    The aim of study was to analyze aerobic capacity and anaerobic power levels of the university students. Total forty university students who is department physical education and department business (age means; 21.15±1.46 years for male and age means; 20.55±1.79 years for female in department physical education), volunteered to participate in this…

  3. Aerobic exercise capacity in post-polio syndrome

    NARCIS (Netherlands)

    Voorn, E.L.

    2015-01-01

    The aim of this thesis was to expand the body of knowledge on the diminished aerobic capacity of individuals with post-polio syndrome (PPS). The studies described in this thesis were based on the assumption that, besides a reduced muscle mass, deconditioning contributes to the severely diminished ae

  4. Aerobic Exercise Equipment Preferences among Older Adults: A Preliminary Investigation.

    Science.gov (United States)

    Looney, Marilyn A.; Rimmer, James H.

    2003-01-01

    Developed an instrument to measure the aerobic exercise equipment preference of a frail older population and applied many-facet Rasch analysis to study construct validity and equipment preferences. Results for 16 participants show the usefulness of many-facet Rasch analysis in guiding instrument revision. (SLD)

  5. Aerobic capacity in children and adolescents with cerebral palsy

    NARCIS (Netherlands)

    Verschuren, Olaf; Takken, Tim

    2010-01-01

    This study described the aerobic capacity [VO(2peak) (ml/kg/min)] in contemporary children and adolescents with cerebral palsy (CP) using a maximal exercise test protocol. Twenty-four children and adolescents with CP classified at Gross Motor Functional Classification Scale (GMFCS) level I or level

  6. Aerobic exercise and intraocular pressure in normotensive and glaucoma patients

    Directory of Open Access Journals (Sweden)

    Chatzibalis Theodosios

    2009-08-01

    Full Text Available Abstract Background With the increasing number of people participating in physical aerobic exercise, jogging in particular, we considered that it would be worth knowing if there are should be limits to the exercise with regard to the intraocular pressure (IOP of the eyes. The purpose of this study is to check IOP in healthy and primary glaucoma patients after aerobic exercise. Methods 145 individuals were subdivided into seven groups: normotensives who exercised regularly (Group A; normotensives in whose right eye (RE timolol maleate 0.5% (Group B, latanoprost 0.005% (Group C, or brimonidine tartrate 0.2% (Group D was instilled; and primary glaucoma patients under monotherapy with β-blockers (Group E, prostaglandin analogues (Group F or combined antiglaucoma treatment (Group G instilled in both eyes. The IOP of both eyes was measured before and after exercise. Results A statistically significant decrease was found in IOP during jogging. The aerobic exercise reduces the IOP in those eyes where a b-blocker, a prostaglandin analogue or an α-agonist was previously instilled. The IOP is also decreased in glaucoma patients who are already under antiglaucoma treatment. Conclusion There is no ocular restriction for simple glaucoma patients in performing aerobic physical activity.

  7. COMMERCIAL-SCALE AEROBIC-ANAEROBIC BIOREACTOR LANDFILL OPERATIONS

    Science.gov (United States)

    A sequential aerobic-anaerobic treatment system has been applied at a commercial scale (3,000 ton per day) municipal solid waste landfill in Kentucky, USA since 2001. In this system, the uppermost layer of landfilled waste is aerated and liquid waste including leachate, surface w...

  8. Intrinsic Aerobic Capacity Sets a Divide for Aging and Longevity

    NARCIS (Netherlands)

    Koch, G.; Kemi, O.J.; Qi, N.; Leng, S.X.; Bijma, P.; Gilligan, L.J.; Wilkinson, J.E.; Grevenhof, van E.M.

    2011-01-01

    Rationale: Low aerobic exercise capacity is a powerful predictor of premature morbidity and mortality for healthy adults as well as those with cardiovascular disease. For aged populations, poor performance on treadmill or extended walking tests indicates closer proximity to future health declines. T

  9. Aerobic Capacity in Children and Adolescents with Cerebral Palsy

    Science.gov (United States)

    Verschuren, Olaf; Takken, Tim

    2010-01-01

    This study described the aerobic capacity [VO[subscript 2peak] (ml/kg/min)] in contemporary children and adolescents with cerebral palsy (CP) using a maximal exercise test protocol. Twenty-four children and adolescents with CP classified at Gross Motor Functional Classification Scale (GMFCS) level I or level II and 336 typically developing…

  10. Group Aquatic Aerobic Exercise for Children with Disabilities

    Science.gov (United States)

    Fragala-Pinkham, Maria; Haley, Stephen M.; O'Neill, Margaret E.

    2008-01-01

    The effectiveness and safety of a group aquatic aerobic exercise program on cardiorespiratory endurance for children with disabilities was examined using an A-B study design. Sixteen children (11 males, five females) age range 6 to 11 years (mean age 9y 7mo [SD 1y 4mo]) participated in this twice-per-week program lasting 14 weeks. The children's …

  11. Sequenced anaerobic-aerobic treatment of hemp pulping wastewaters.

    NARCIS (Netherlands)

    Kortekaas, S.

    1998-01-01

    Biological treatment is an indispensable instrument for water management of non-wood pulp mills, either as internal measure to enable progressive closure of water cycles, or as end of pipe treatment. In this thesis, the sequenced anaerobic-aerobic treatment of hemp ( Cannabis sativa L. ) pulping was

  12. White matter connectivity and aerobic fitness in male adolescents

    Directory of Open Access Journals (Sweden)

    Megan M. Herting

    2014-01-01

    Full Text Available Exercise has been shown to have positive effects on the brain and behavior throughout various stages of the lifespan. However, little is known about the impact of exercise on neurodevelopment during the adolescent years, particularly with regard to white matter microstructure, as assessed by diffusion tensor imaging (DTI. Both tract-based spatial statistics (TBSS and tractography-based along-tract statistics were utilized to examine the relationship between white matter microstructure and aerobic exercise in adolescent males, ages 15–18. Furthermore, we examined the data by both (1 grouping individuals based on aerobic fitness self-reports (high fit (HF vs. low fit (LF, and (2 using VO2 peak as a continuous variable across the entire sample. Results showed that HF youth had an overall higher number of streamline counts compared to LF peers, which was driven by group differences in corticospinal tract (CST and anterior corpus callosum (Fminor. In addition, VO2 peak was negatively related to FA in the left CST. Together, these results suggest that aerobic fitness relates to white matter connectivity and microstructure in tracts carrying frontal and motor fibers during adolescence. Furthermore, the current study highlights the importance of considering the environmental factor of aerobic exercise when examining adolescent brain development.

  13. Aerobic Digestion. Biological Treatment Process Control. Instructor's Guide.

    Science.gov (United States)

    Klopping, Paul H.

    This unit on aerobic sludge digestion covers the theory of the process, system components, factors that affect the process performance, standard operational concerns, indicators of steady-state operations, and operational problems. The instructor's guide includes: (1) an overview of the unit; (2) lesson plan; (3) lecture outline (keyed to a set of…

  14. Relative importance of aerobic versus resistance training for healthy aging

    Science.gov (United States)

    This review will focus on the importance of aerobic and resistance modes of physical activity for healthy aging as supported by findings in 2007. In line with public health recommendations, several studies in 2007 employed an exercise paradigm that combined both modes of physical activity. While a...

  15. In situ aerobic cometabolism of chlorinated solvents: a review.

    Science.gov (United States)

    Frascari, Dario; Zanaroli, Giulio; Danko, Anthony S

    2015-01-01

    The possible approaches for in situ aerobic cometabolism of aquifers and vadose zones contaminated by chlorinated solvents are critically evaluated. Bioaugmentation of resting-cells previously grown in a fermenter and in-well addition of oxygen and growth substrate appear to be the most promising approaches for aquifer bioremediation. Other solutions involving the sparging of air lead to satisfactory pollutant removals, but must be integrated by the extraction and subsequent treatment of vapors to avoid the dispersion of volatile chlorinated solvents in the atmosphere. Cometabolic bioventing is the only possible approach for the aerobic cometabolic bioremediation of the vadose zone. The examined studies indicate that in situ aerobic cometabolism leads to the biodegradation of a wide range of chlorinated solvents within remediation times that vary between 1 and 17 months. Numerous studies include a simulation of the experimental field data. The modeling of the process attained a high reliability, and represents a crucial tool for the elaboration of field data obtained in pilot tests and for the design of the full-scale systems. Further research is needed to attain higher concentrations of chlorinated solvent degrading microbes and more reliable cost estimates. Lastly, a procedure for the design of full-scale in situ aerobic cometabolic bioremediation processes is proposed.

  16. Kinetic comparisons of mesophilic and thermophilic aerobic biomass

    NARCIS (Netherlands)

    Vogelaar, J.C.T.; Klapwijk, A.; Temmink, H.; Lier, van J.B.

    2003-01-01

    Kinetic parameters describing growth and decay of mesophilic (30degreesC) and thermophilic (55degreesC) aerobic biomass were determined in continuous and batch experiments by using oxygen uptake rate measurements
    Kinetic parameters describing growth and decay of mesophilic (30degreesC) and therm

  17. AEROBIC BIODEGRADATION OF GASOLINE OXYGENATES MTBE AND TBA

    Science.gov (United States)

    MTBE degradation was investigated using a continuously stirred tank reactor (CSTR) with biomass retention (porous pot reactor) operated under aerobic conditions. MTBE was fed to the reactor at an influent concentration of 150 mg/l (1.70 mmol/l). A second identifical rector was op...

  18. Strength training and aerobic exercise training for muscle disease (Review)

    NARCIS (Netherlands)

    Voet, N.B.M.; Kooi, E.L. van der; Riphagen, I.I.; Lindeman, E.; Engelen, B.G.M. van; Geurts, A.C.H.

    2013-01-01

    BACKGROUND: Strength training or aerobic exercise programmes might optimise muscle and cardiorespiratory function and prevent additional disuse atrophy and deconditioning in people with a muscle disease. This is an update of a review first published in 2004. OBJECTIVES: To examine the safety and eff

  19. Reductive Dechlorination of Trichloroethylene and Tetrachloroethylene under Aerobic Conditions in a Sediment Column

    OpenAIRE

    Enzien, Michael V.; Picardal, Flynn; Terry C Hazen; Arnold, R. G.; Fliermans, Carl B.

    1994-01-01

    Biodegradation of trichloroethylene and tetrachloroethylene under aerobic conditions was studied in a sediment column. Cumulative mass balances indicated 87 and 90% removal for trichloroethylene and tetrachloroethylene, respectively. These studies suggest the potential for simultaneous aerobic and anaerobic biotransformation processes under bulk aerobic conditions.

  20. Aerobic Development of Elite Youth Ice Hockey Players.

    Science.gov (United States)

    Leiter, Jeff R; Cordingley, Dean M; MacDonald, Peter B

    2015-11-01

    Ice hockey is a physiologically complex sport requiring aerobic and anaerobic energy metabolism. College and professional teams often test aerobic fitness; however, there is a paucity of information regarding aerobic fitness of elite youth players. Without this knowledge, training of youth athletes to meet the standards of older age groups and higher levels of hockey may be random, inefficient, and or effective. Therefore, the purpose of this study was to determine the aerobic fitness of elite youth hockey players. A retrospective database review was performed for 200 male AAA hockey players between the ages of 13 and 17 (age, 14.4 ± 1.2 years; height, 174.3 ± 8.5 cm; body mass, 67.2 ± 11.5 kg; body fat, 9.8 ± 3.5%) before the 2012-13 season. All subjects performed a graded exercise test on a cycle ergometer, whereas expired air was collected by either a Parvo Medics TrueOne 2400 or a CareFusion Oxycon Mobile metabolic cart to determine maximal oxygen consumption (V[Combining Dot Above]O2max). Body mass, absolute V[Combining Dot Above]O2max, and the power output achieved during the last completed stage increased in successive age groups from age 13 to 15 years (p ≤ 0.05). Ventilatory threshold (VT) expressed as a percentage of V[Combining Dot Above]O2max and the heart rate (HR) at which VT occurred decreased between the ages of 13 and 14 years (p ≤ 0.05), whereas the V[Combining Dot Above]O2 at which VT occurred increased from the age of 14-15 years. There were no changes in relative V[Combining Dot Above]O2max or HRmax between any successive age groups. The aerobic fitness levels of elite youth ice hockey players increased as players age and mature physically and physiologically. However, aerobic fitness increased to a lesser extent at older ages. This information has the potential to influence off-season training and maximize the aerobic fitness of elite amateur hockey players, so that these players can meet standards set by advanced elite age groups.

  1. Mechanisms of aerobic performance impairment with heat stress and dehydration.

    Science.gov (United States)

    Cheuvront, Samuel N; Kenefick, Robert W; Montain, Scott J; Sawka, Michael N

    2010-12-01

    Environmental heat stress can challenge the limits of human cardiovascular and temperature regulation, body fluid balance, and thus aerobic performance. This minireview proposes that the cardiovascular adjustments accompanying high skin temperatures (T(sk)), alone or in combination with high core body temperatures (T(c)), provide a primary explanation for impaired aerobic exercise performance in warm-hot environments. The independent (T(sk)) and combined (T(sk) + T(c)) effects of hyperthermia reduce maximal oxygen uptake (Vo(2max)), which leads to higher relative exercise intensity and an exponential decline in aerobic performance at any given exercise workload. Greater relative exercise intensity increases cardiovascular strain, which is a prominent mediator of rated perceived exertion. As a consequence, incremental or constant-rate exercise is more difficult to sustain (earlier fatigue) or requires a slowing of self-paced exercise to achieve a similar sensation of effort. It is proposed that high T(sk) and T(c) impair aerobic performance in tandem primarily through elevated cardiovascular strain, rather than a deterioration in central nervous system (CNS) function or skeletal muscle metabolism. Evaporative sweating is the principal means of heat loss in warm-hot environments where sweat losses frequently exceed fluid intakes. When dehydration exceeds 3% of total body water (2% of body mass) then aerobic performance is consistently impaired independent and additive to heat stress. Dehydration augments hyperthermia and plasma volume reductions, which combine to accentuate cardiovascular strain and reduce Vo(2max). Importantly, the negative performance consequences of dehydration worsen as T(sk) increases.

  2. Acute aerobic exercise modulates primary motor cortex inhibition.

    Science.gov (United States)

    Mooney, Ronan A; Coxon, James P; Cirillo, John; Glenny, Helen; Gant, Nicholas; Byblow, Winston D

    2016-12-01

    Aerobic exercise can enhance neuroplasticity although presently the neural mechanisms underpinning these benefits remain unclear. One possible mechanism is through effects on primary motor cortex (M1) function via down-regulation of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). The aim of the present study was to examine how corticomotor excitability (CME) and M1 intracortical inhibition are modulated in response to a single bout of moderate intensity aerobic exercise. Ten healthy right-handed adults were participants. Single- and paired-pulse transcranial magnetic stimulation was applied over left M1 to obtain motor-evoked potentials in the right flexor pollicis brevis. We examined CME, cortical silent period (SP) duration, short- and long-interval intracortical inhibition (SICI, LICI), and late cortical disinhibition (LCD), before and after acute aerobic exercise (exercise session) or an equivalent duration without exercise (control session). Aerobic exercise was performed on a cycle ergometer for 30 min at a workload equivalent to 60 % of maximal cardiorespiratory fitness (VO2 peak; heart rate reserve = 75 ± 3 %, perceived exertion = 13.5 ± 0.7). LICI was reduced at 10 (52 ± 17 %, P = 0.03) and 20 min (27 ± 8 %, P = 0.03) post-exercise compared to baseline (13 ± 4 %). No significant changes in CME, SP duration, SICI or LCD were observed. The present study shows that GABAB-mediated intracortical inhibition may be down-regulated after acute aerobic exercise. The potential effects this may have on M1 plasticity remain to be determined.

  3. Technical note: enumeration of mesophilic aerobes in milk: evaluation of standard official protocols and Petrifilm aerobic count plates.

    Science.gov (United States)

    Freitas, R; Nero, L A; Carvalho, A F

    2009-07-01

    Enumeration of mesophilic aerobes (MA) is the main quality and hygiene parameter for raw and pasteurized milk. High levels of these microorganisms indicate poor conditions in production, storage, and processing of milk, and also the presence of pathogens. Fifteen raw and 15 pasteurized milk samples were submitted for MA enumeration by a conventional plating method (using plate count agar) and Petrifilm Aerobic Count plates (3M, St. Paul, MN), followed by incubation according to 3 official protocols: IDF/ISO (incubation at 30 degrees C for 72 h), American Public Health Association (32 degrees C for 48 h), and Brazilian Ministry of Agriculture (36 degrees C for 48 h). The results were compared by linear regression and ANOVA. Considering the results from conventional methodology, good correlation indices and absence of significant differences between mean counts were observed, independent of type of milk sample (raw or pasteurized) and incubation conditions (IDF/ISO, American Public Health Association, or Ministry of Agriculture). Considering the results from Petrifilm Aerobic Count plates, good correlation indices and absence of significant differences were only observed for raw milk samples. The microbiota of pasteurized milk interfered negatively with the performance of Petrifilm Aerobic Count plates, probably because of the presence of microorganisms that poorly reduce the dye indicator of this system.

  4. Effects of Aerobic Exercise Based upon Heart Rate at Aerobic Threshold in Obese Elderly Subjects with Type 2 Diabetes

    Science.gov (United States)

    Donini, Lorenzo Maria

    2015-01-01

    In obese diabetic subjects, a correct life style, including diet and physical activity, is part of a correct intervention protocol. Thus, the aim of this study was to evaluate the effects of aerobic training intervention, based on heart rate at aerobic gas exchange threshold (AerTge), on clinical and physiological parameters in obese elderly subjects with type 2 diabetes (OT2DM). Thirty OT2DM subjects were randomly assigned to an intervention (IG) or control group (CG). The IG performed a supervised aerobic exercise training based on heart rate at AerTge whereas CG maintained their usual lifestyle. Anthropometric measures, blood analysis, peak oxygen consumption (V˙O2peak), metabolic equivalent (METpeak), work rate (WRpeak), and WRAerTge were assessed at baseline and after intervention. After training, patients enrolled in the IG had significantly higher (P < 0.001) V˙O2peak, METpeak, WRpeak, and WRAerTge and significantly lower (P < 0.005) weight, BMI, %FM, and waist circumference than before intervention. Both IG and CG subjects had lower glycated haemoglobin levels after intervention period. No significant differences were found for all the other parameters between pre- and posttraining and between groups. Aerobic exercise prescription based upon HR at AerTge could be a valuable physical intervention tool to improve the fitness level and metabolic equilibrium in OT2DM patients. PMID:26089890

  5. The origin of atmospheric oxygen on Earth: the innovation of oxygenic photosynthesis.

    Science.gov (United States)

    Dismukes, G C; Klimov, V V; Baranov, S V; Kozlov, Y N; DasGupta, J; Tyryshkin, A

    2001-02-27

    The evolution of O(2)-producing cyanobacteria that use water as terminal reductant transformed Earth's atmosphere to one suitable for the evolution of aerobic metabolism and complex life. The innovation of water oxidation freed photosynthesis to invade new environments and visibly changed the face of the Earth. We offer a new hypothesis for how this process evolved, which identifies two critical roles for carbon dioxide in the Archean period. First, we present a thermodynamic analysis showing that bicarbonate (formed by dissolution of CO(2)) is a more efficient alternative substrate than water for O(2) production by oxygenic phototrophs. This analysis clarifies the origin of the long debated "bicarbonate effect" on photosynthetic O(2) production. We propose that bicarbonate was the thermodynamically preferred reductant before water in the evolution of oxygenic photosynthesis. Second, we have examined the speciation of manganese(II) and bicarbonate in water, and find that they form Mn-bicarbonate clusters as the major species under conditions that model the chemistry of the Archean sea. These clusters have been found to be highly efficient precursors for the assembly of the tetramanganese-oxide core of the water-oxidizing enzyme during biogenesis. We show that these clusters can be oxidized at electrochemical potentials that are accessible to anoxygenic phototrophs and thus the most likely building blocks for assembly of the first O(2) evolving photoreaction center, most likely originating from green nonsulfur bacteria before the evolution of cyanobacteria.

  6. Does aerobic exercise improve or impair cardiorespiratory fitness and health among cleaners?

    DEFF Research Database (Denmark)

    Korshøj, Mette; Lidegaard, Mark; Skotte, Jørgen H;

    2015-01-01

    OBJECTIVE: It is unknown if aerobic exercise overloads or improves the cardiovascular system among workers with high occupational physical activity. This was investigated in a worksite randomized controlled trial (RCT) of aerobic exercise among cleaners. METHODS: We randomized 116 cleaners between...... 18-65 years. The aerobic exercise group (N=57) performed worksite aerobic exercise (30 minutes twice a week) and the reference group (N=59) received lectures. Cardiorespiratory fitness, blood pressure (BP) and diurnal heart rate (HR) for measuring aerobic workload [% HR reserve (% HRR)] were...

  7. Aerobic exercise reduces biomarkers related to cardiovascular risk among cleaners

    DEFF Research Database (Denmark)

    Korshøj, Mette; Ravn, Marie Højbjerg; Holtermann, Andreas;

    2016-01-01

    PURPOSE: Blue-collar workers have an increased risk of cardiovascular disease. Accordingly, elevated levels of biomarkers related to risk of cardiovascular disease, such as high-sensitive C-reactive protein, have been observed among blue-collar workers. The objective was to examine whether....... The reference group (n = 59) received lectures, and the aerobic exercise group (n = 57) performed worksite aerobic exercise (30 min twice a week). Levels of biomarkers (high-sensitive C-reactive protein, fibrinogen, cholesterol, low- and high-density lipoprotein cholesterol and triglyceride) were collected...... at baseline and after 4 months. A repeated-measure, multi-adjusted, mixed-model intention-to-treat analysis was applied to compare between-group differences. The study was registered as ISRCTN86682076. RESULTS: Significant (p high...

  8. Diagnosis Aerobic Component of Operational Preparedness Skill Players

    Directory of Open Access Journals (Sweden)

    Vasylyuk Vasyl

    2017-01-01

    Full Text Available Considerable importance for the control system, selection and orientation of the players on the stage long-term preparation plays a selection of effective methods of testing the various components of functional fitness athlete for timely, objective information about the players. The use of reliable scientific methods of effective monitoring of the athlete contributes to the further improvement of skills, increase athletic achievements. The purpose of this article is to describe and summarize modern methods of diagnosis and development of aerobic component of operational preparedness players qualifications. This article describes methods that actively and effectively used in leading European football teams. Specifically Yo-Yo test, test Shuttle (beep-test, Bangsbo test, test Hoff-Helgerud, test Conconi, Wingate-test. These tests have a high level of reliability and security mechanisms for assessing aerobic power players.

  9. Catalytic aerobic oxidation of bio-renewable chemicals

    DEFF Research Database (Denmark)

    Gorbanev, Yury

    , EDS, XRF and other methods. Supported gold and ruthenium hydroxide catalyst systems were explored for the aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDA), a potential polymer building block for the plastic industry, or its dimethyl ester (FDMC). High product...... for the exclusive production of intermediate products of the oxidation. Catalysts consisting of Ru(OH)x deposited on metal oxide supports, such as, for instance, CeO2 and MgAl2O4, were employed in the aerobic oxidation of HMF in different ”green” reaction media, e.g. water and various ionic liquids, under base....... Thus, the oxidative transformations of biomass-derived chemicals over different gold and ruthenium-based catalyst systems with oxygen as the abundant oxidant were explored....

  10. Practical Methods for Aerobic Composting of Cattle Manure

    Directory of Open Access Journals (Sweden)

    Gheorghina Preda

    2013-05-01

    Full Text Available Fresh manure of cattle was subjected to aerobic composting process in two ways: mixed with chopped stalks of sunflower and triticale straw. The composting process has been monitored by sampling periodic chemical and biochemical samples to determine pH value and the quantity of nitrogen, phosphorus and potassium. It was also registered the temperature and humidity evolution of gathering together of materials that are subject of biodegradation, and finally we calculated the yield of composting. It was found that the oxygen is indispensable to the composting process because during the period of warm fermentation, the aerobic bacteria need a regeneration of oxygen to continue the oxidation of carbon. A decrease in the oxygen concentration below 6 % slows down the microbial activity. The best compost was obtained in the case of ratio C : N about 20 - 40 : 1.

  11. Aerobic vs anaerobic exercise training effects on the cardiovascular system.

    Science.gov (United States)

    Patel, Harsh; Alkhawam, Hassan; Madanieh, Raef; Shah, Niel; Kosmas, Constantine E; Vittorio, Timothy J

    2017-02-26

    Physical exercise is one of the most effective methods to help prevent cardiovascular (CV) disease and to promote CV health. Aerobic and anaerobic exercises are two types of exercise that differ based on the intensity, interval and types of muscle fibers incorporated. In this article, we aim to further elaborate on these two categories of physical exercise and to help decipher which provides the most effective means of promoting CV health.

  12. Aerobic vs anaerobic exercise training effects on the cardiovascular system

    Science.gov (United States)

    Patel, Harsh; Alkhawam, Hassan; Madanieh, Raef; Shah, Niel; Kosmas, Constantine E; Vittorio, Timothy J

    2017-01-01

    Physical exercise is one of the most effective methods to help prevent cardiovascular (CV) disease and to promote CV health. Aerobic and anaerobic exercises are two types of exercise that differ based on the intensity, interval and types of muscle fibers incorporated. In this article, we aim to further elaborate on these two categories of physical exercise and to help decipher which provides the most effective means of promoting CV health. PMID:28289526

  13. Critical Period of Weed Control in Aerobic Rice

    OpenAIRE

    Anwar, M. P.; A. S. Juraimi; Samedani, B.; Puteh, A.; Man, A.

    2012-01-01

    Critical period of weed control is the foundation of integrated weed management and, hence, can be considered the first step to design weed control strategy. To determine critical period of weed control of aerobic rice, field trials were conducted during 2010/2011 at Universiti Putra Malaysia. A quantitative series of treatments comprising two components, (a) increasing duration of weed interference and (b) increasing length of weed-free period, were imposed. Critical period was determined th...

  14. Myocardial damage after continuous aerobic and anaerobic exercise in rats

    Directory of Open Access Journals (Sweden)

    Rostika Flora

    2013-12-01

    Full Text Available Background: Regular physical activity is highly recommended in preventive, curative, and rehabilitative programs in order to promote health, especially cardiovascular health. However, physical activity can also cause sudden death. In athletes, sudden death may occur during sport competitions, with myocardial infarction as the most common etiology. It is suspected that continuous training without any rest-day play a role in cardiac muscle damage and sudden death during competition. Our study was aimed to learn about cardiac muscle adaptation on continuous aerobic and anaerobic physical activity without any rest-day. Methods: The specimens in our study were cardiac muscle tissue obtained from rats that had performed aerobic and anaerobic physical activity on treadmill for 1, 3, 7, and 10 days without any rest-day. Blood gas analysis and hematological assessment were used as parameters of systemic adaptation to hypoxia during physical activity. Moreover, histopathology of cardiac muscle tissue was performed as parameter for cardiac muscle damage.Results: The results showed that aerobic and anaerobic physical activity caused a systemic hypoxic condition and triggered adaptation responses. Cardiac muscle damage occurred on the 10th day in both treatment groups, with more severe damage observed in the group with anaerobic physical activity. The tissue protein level in the anaerobic group increased progressively on the 10th day.Conclusion: Physical activity may result in hypoxia and systemic adaptation. Aerobic and anaerobic physical activities performed for 10 days without any rest-day may cause cardiac muscle damage. (Med J Indones. 2013;22:209-14. doi: 10.13181/mji.v22i4.601Keywords: Cardiac muscle, cardiac muscle damage, histopathology, physical activity

  15. On Aerobic Exercise and Behavioral and Neural Plasticity

    OpenAIRE

    Caitlin Peplinski; Ami Patel; Berggren, Kiersten L.; Kerr, Abigail L.; Rodney A. Swain; Angela M. Sikorski

    2012-01-01

    Aerobic exercise promotes rapid and profound alterations in the brain. Depending upon the pattern and duration of exercise, these changes in the brain may extend beyond traditional motor areas to regions and structures normally linked to learning, cognition, and emotion. Exercise-induced alterations may include changes in blood flow, hormone and growth factor release, receptor expression, angiogenesis, apoptosis, neurogenesis, and synaptogenesis. Together, we believe that these changes underl...

  16. Echinacea Supplementation: Does it Really Improve Aerobic Fitness?

    OpenAIRE

    Baumann, Cory W.; Kwak, Dongmin

    2016-01-01

    [Purpose] Echinacea is an herbal supplement used by endurance athletes for its performance boosting properties. It is thought that Echinacea improves the blood’s oxygen carrying capacity by increasing production of erythropoietin (EPO), a glycoprotein that regulates red blood cell formation. Subsequently, these changes would lead to an overall improvement in maximal oxygen uptake (VO2max) and running economy (RE), two markers of aerobic fitness. The purpose of this review is to briefly discus...

  17. Comparison of two aerobic field tests in young tennis players.

    Science.gov (United States)

    Fargeas-Gluck, Marie-Agnès; Léger, Luc A

    2012-11-01

    This study compares the maximal responses of a new aerobic tennis field test, the NAVTEN to a known aerobic field test, often used with young tennis players, that is, the continuous multistage 20-m shuttle run test (20-m SRT). The NAVTEN is an intermittent (1-minute/1-minute) multistage test with side-to-side displacements and ball hitting. Ten young elite tennis players aged 12.9 ± 0.3 (mean ± SD) randomly performed both tests and were continuously monitored for heart rate (HR) and oxygen uptake (V[Combining Dot Above]O2) using the Vmax ST (Sensormedics). The 20-m SRT and NAVTEN show similar HRpeak (202 ± 6.1 vs. 208 ± 9.5, respectively) and V[Combining Dot Above]O2peak (54.2 ± 5.9 vs. 54.9 ± 6.0 ml·kg·min). Pearson correlations between both tests were 0.88 and 0.92 for V[Combining Dot Above]O2peak and maximal speed, respectively. The NAVTEN yielded V[Combining Dot Above]O2peak values that are typical for active subjects of that age and are similar to the 20-m SRT supporting its use to measure aerobic fitness of young tennis players in specific and entertaining field conditions. The fact that two-thirds of the tennis players achieved a different ranking (±1 rank) with the NAVTEN and the 20-m SRT suggests that the NAVTEN may be more specific than the 20-m SRT to assess aerobic fitness of tennis players. From a practical point of view, the NAVTEN test is more specific and pedagogical for young tennis players even though both tests yield similar maximal values.

  18. Aerobic oxidation assisted by ligand-free palladium catalysts

    Institute of Scientific and Technical Information of China (English)

    Jia Rui Wang; Chu Ting Yang; Lei Liu; Qing Xiang Guo

    2007-01-01

    Aerobic oxidation of electron-rich benzylic and phenyl allylic alcohols was achieved with high yields with only 0.1 mol.% ofPd(OAc)2 catalyst in the absence of any ligand. This procedure was expected to be valuable for realistic industrial-scale applications from both economic as well as environmental points of view.(C) 2006 Qing Xiang Guo. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

  19. Copper-Catalyzed Aerobic C–H Trifluoromethylation of Phenanthrolines

    Science.gov (United States)

    Zhu, Cheng-Liang; Zhang, Yong-Qiang; Yuan, Yong-An

    2016-01-01

    Direct C–H trifluoromethylation of heterocycles is a valuable transformation. In particular, nonprecious metal-catalyzed C–H trifluoromethylation processes, which do not proceed through CF3 radical species, have been less developed. In this cluster report, a new copper-catalyzed aerobic C–H trifluoromethylation of phenanthrolines is described. This transformation affords trifluoromethylated phenanthrolines that have not been synthesized and preliminary mechanistic studies suggest that the CF3 group transfer may occur through cooperative activation. PMID:26855477

  20. Microbial fuel cells with highly active aerobic biocathodes

    Science.gov (United States)

    Milner, Edward M.; Popescu, Dorin; Curtis, Tom; Head, Ian M.; Scott, Keith; Yu, Eileen H.

    2016-08-01

    Microbial fuel cells (MFCs), which convert organic waste to electricity, could be used to make the wastewater infrastructure more energy efficient and sustainable. However, platinum and other non-platinum chemical catalysts used for the oxygen reduction reaction (ORR) at the cathode of MFCs are unsustainable due to their high cost and long-term degradation. Aerobic biocathodes, which use microorganisms as the biocatalysts for cathode ORR, are a good alternative to chemical catalysts. In the current work, high-performing aerobic biocathodes with an onset potential for the ORR of +0.4 V vs. Ag/AgCl were enriched from activated sludge in electrochemical half-cells poised at -0.1 and + 0.2 V vs. Ag/AgCl. Gammaproteobacteria, distantly related to any known cultivated gammaproteobacterial lineage, were identified as dominant in these working electrode biofilms (23.3-44.3% of reads in 16S rRNA gene Ion Torrent libraries), and were in very low abundance in non-polarised control working electrode biofilms (0.5-0.7%). These Gammaproteobacteria were therefore most likely responsible for the high activity of biologically catalysed ORR. In MFC tests, a high-performing aerobic biocathode increased peak power 9-fold from 7 to 62 μW cm-2 in comparison to an unmodified carbon cathode, which was similar to peak power with a platinum-doped cathode at 70 μW cm-2.

  1. Aerobic Microbial Respiration In Oceanic Oxygen Minimum Zones.

    Science.gov (United States)

    Kalvelage, Tim; Lavik, Gaute; Jensen, Marlene M; Revsbech, Niels Peter; Löscher, Carolin; Schunck, Harald; Desai, Dhwani K; Hauss, Helena; Kiko, Rainer; Holtappels, Moritz; LaRoche, Julie; Schmitz, Ruth A; Graco, Michelle I; Kuypers, Marcel M M

    2015-01-01

    Oxygen minimum zones are major sites of fixed nitrogen loss in the ocean. Recent studies have highlighted the importance of anaerobic ammonium oxidation, anammox, in pelagic nitrogen removal. Sources of ammonium for the anammox reaction, however, remain controversial, as heterotrophic denitrification and alternative anaerobic pathways of organic matter remineralization cannot account for the ammonium requirements of reported anammox rates. Here, we explore the significance of microaerobic respiration as a source of ammonium during organic matter degradation in the oxygen-deficient waters off Namibia and Peru. Experiments with additions of double-labelled oxygen revealed high aerobic activity in the upper OMZs, likely controlled by surface organic matter export. Consistently observed oxygen consumption in samples retrieved throughout the lower OMZs hints at efficient exploitation of vertically and laterally advected, oxygenated waters in this zone by aerobic microorganisms. In accordance, metagenomic and metatranscriptomic analyses identified genes encoding for aerobic terminal oxidases and demonstrated their expression by diverse microbial communities, even in virtually anoxic waters. Our results suggest that microaerobic respiration is a major mode of organic matter remineralization and source of ammonium (~45-100%) in the upper oxygen minimum zones, and reconcile hitherto observed mismatches between ammonium producing and consuming processes therein.

  2. Aerobic Microbial Respiration In Oceanic Oxygen Minimum Zones.

    Directory of Open Access Journals (Sweden)

    Tim Kalvelage

    Full Text Available Oxygen minimum zones are major sites of fixed nitrogen loss in the ocean. Recent studies have highlighted the importance of anaerobic ammonium oxidation, anammox, in pelagic nitrogen removal. Sources of ammonium for the anammox reaction, however, remain controversial, as heterotrophic denitrification and alternative anaerobic pathways of organic matter remineralization cannot account for the ammonium requirements of reported anammox rates. Here, we explore the significance of microaerobic respiration as a source of ammonium during organic matter degradation in the oxygen-deficient waters off Namibia and Peru. Experiments with additions of double-labelled oxygen revealed high aerobic activity in the upper OMZs, likely controlled by surface organic matter export. Consistently observed oxygen consumption in samples retrieved throughout the lower OMZs hints at efficient exploitation of vertically and laterally advected, oxygenated waters in this zone by aerobic microorganisms. In accordance, metagenomic and metatranscriptomic analyses identified genes encoding for aerobic terminal oxidases and demonstrated their expression by diverse microbial communities, even in virtually anoxic waters. Our results suggest that microaerobic respiration is a major mode of organic matter remineralization and source of ammonium (~45-100% in the upper oxygen minimum zones, and reconcile hitherto observed mismatches between ammonium producing and consuming processes therein.

  3. Concentric left ventricular morphology in aerobically trained kayak canoeists.

    Science.gov (United States)

    Gates, Phillip E; Campbell, Ian G; George, Keith P

    2004-09-01

    The aim of the present study was to test the hypothesis that upper body aerobically trained athletes (kayak canoeists) would have greater left ventricular wall thickness, but similar left ventricular diastolic chamber dimensions, compared with recreationally active and sedentary men. Ultrasound echocardiography was used to determine cardiac structure and function in highly trained kayak canoeists (n = 10), moderately active (n = 10) and sedentary men (n = 10). The septal and posterior left ventricular walls were approximately 0.2 cm thicker in kayak canoeists (P kayak canoeists had a concentric pattern of left ventricular adaptation to aerobic upper body training. Scaling the data to body composition indices had no effect on the outcome of the statistical analysis. There were no differences in resting Doppler left ventricular diastolic or systolic function among the groups. Ejection fraction was lower in the kayak canoeists, but the magnitude of the difference was within the normal variability for this measurement. Thus aerobically upper body trained athletes demonstrated a concentric pattern of cardiac enlargement, but resting left ventricle function was not different between athletes, moderately active and sedentary individuals.

  4. Combined alkaline and ultrasonic pretreatment of sludge before aerobic digestion

    Institute of Scientific and Technical Information of China (English)

    JIN Yiying; LI Huan; MAHAR Rasool Bux; WANG Zhiyu; NIE Yongfeng

    2009-01-01

    Alkaline and ultrasonic sludge disintegration can both be used as pretreatments of waste activated sludge (WAS) for improving the subsequent anaerobic or aerobic digestion. The pretreatment has been carried out using different combination of these two methods in this study. The effect was evaluated based on the quantity of soluble chemical oxygen demand (SCOD) in the pretreated sludge as well as the degradation of organic matter in the following aerobic digestion. For WAS samples with combined pretreatment, the released COD was in high level than those with ultrasonic or alkaline treatment. When combined with the same ultrasonic treatment, NaOH treatment resulted in more solubilization of WAS than Ca(OH)2. For combined NaOH and ultrasonic treatments with different sequences, the released COD were in the order: simultaneous treatment > ultrasonic treatment following NaOH treatment > NaOH treatment following ultrasonic treatment. For simultaneous treatment, low NaOH dosage (100 g/kg dry solid), short duration (30 min) of NaOH treatment, and low ultrasonic specific energy (7 500 kJ/kg dry solid) were beneficial for sludge disintegration. Using combined NaOH and ultrasonic pretreatment with the optimium parameters, the degradation efficiency of organic matter was increased from 38.0% to 50.7%, which is much higher than with ultrasonic (42.5%) or with NaOH pretreatment (43.5%) in the subsequent aerobic digestion at the same retention time.

  5. Color Changes of Package Silage In Period of Aerobic Stability

    Directory of Open Access Journals (Sweden)

    F. Toruk

    2010-01-01

    Full Text Available In this study, changes on color of the silage surface, chemical and microbiological parameters in six days period of aerobic stability of package silage were investigated. For this purpose, the effect of the silage additive materials and treatments dose also were examined. Treatments were determined as Control (C, Silo-king firm dose (FD, Silo-King double dose (D2, Sim-Silage firm dose (SF, and Sim-Silage double dose (S2.Maize was ensiled using a package silage machine. The package silages opened after three months storage was analyzed for colors during aerobic exposure. In this research, yellowness (yı* indicates were also measured to show the effect of fermentation process on the silage color properties. As the result of experiment, it was found that aerobic stability have significant effects on color of the silage surface (all parameters statistically (p<0.05. The lowest color alteration (ΔE was estimated as 8.96 in S2 treatment. The color alteration also was increased 96 h when increased at pH and temperature. The highest CO2 values were found at firm dose treatments.

  6. Improving aerobic capacity through active videogames: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Jorge Luiz de Brito-Gomes

    2015-09-01

    Full Text Available AbstractThe rate of peak workload improvement between different types of Active Video Games (AVG in young sedentary adults was investigated. Aerobic capacity improvement after a 6-week intervention between AVG types was also compared. Twenty participants, after baseline assessments, were randomized into one of three parallel groups: structured AVG (n= 6, unstructured AVG (n= 7 and a control group (n= 7. Participants played their respective AVG 3 times a week for 6-weeks (30 minutes-session. The control group maintained normal activities. Both structured and unstructured AVG improved peak workload after four weeks but only the structured group maintained this improvement through week five and six. Aerobic capacity improved in the unstructured (Pre: 36.0 ± 5.2ml.kg.min-¹,Post: 39.7 ± 4.9ml.kg.min-¹, p = .038 and structured AVG (Pre: 39.0 ± 5.9ml.kg.min-¹,Post: 47.8 ± 4.3ml.kg.min-¹, p = .006 groups. Structured AVG provide greater health benefits to aerobic capacity and peak workload in young sedentary but otherwise healthy males relative to unstructured AVG.

  7. Aerobic exercise in children with oxidative phosphorylation defects

    Directory of Open Access Journals (Sweden)

    Luuk Schreuder

    2010-03-01

    Full Text Available Fatigue and exercise intolerance are symptoms in children with metabolic myopathy. Frequently this is combined with muscle pain in children with mitochondrial myopathy. Offering therapeutic advice remains challenging in this patient group. Here we describe five children above the age of four years, with normal intelligence, myopathy, exercise intolerance, motor developmental delay, and fatigue, who were diagnosed with a mitochondrial dysfunction. Based on the positive experience of condition training in adults with mitochondrial disease and inactivity, aerobic exercise training was advised for all the children. Because of the lack of clear protocols for individualized mitochondrial myopathies, regular training was initiated. The Movement Assessment Battery of Children, the Jamar dynamometer for grip force, and the Bruce protocol treadmill test were applied for evaluation. No patient showed significant disease progression on a weekly scheme of strength training or on aerobic training during periods varying between 6 and 18 months. Only one out of the five patients has shown an improvement after a period of structured, aerobic training, demonstrating good compliance and motivation over the course of 18 months. Some patients developed severe muscle pain after explosive exercise. Even in a relatively homogenous, intelligent group of patients and motivated parents, we could not reach full compliance. With our case studies, we would like to draw attention to the importance and pitfalls of movement therapy in children with mitochondrial disease.

  8. Stimulated Growth of Aerobic Microbes Using Calcium Peroxide

    Institute of Scientific and Technical Information of China (English)

    LIU Shejiang; LI Mujin; JIANG Bin; LI Xingang

    2006-01-01

    With continuous and slow oxygen-release characteristic,calcium peroxide (CaO2) has been a new source of supplying oxygen for aerobic microbes in bioremediation of contaminated groundwater.Batch experiments were conducted to evaluate the oxygen-release rate of CaO2 reacting with water,the regulation of high pH,as well as the growth of mixed aerobic microbes in the medium containing CaO2.The results show that the oxygen-release process of CaO2 comprises three phases.In the first phase,dissolved oxygen levels of water increased sharply,and average oxygen-release rates increased as the adding weight of CaO2 increased.However,the rates almost ly.As the necessary components of medium,potassium dihydrogen phosphate (KH2PO4) and ammonium sulphate ((NH4)2SO4) at a certain ratio could regulate pH caused by CaO2 from 12.1 to the range of 6.5-8.5,which is helpful for microbial growth.In addition,diauxic growth curve observed in the medium containing CaO2 suggested that the growth of mixed aerobic microbes could be stimulated by the addition of CaO2.

  9. Electric motor assisted bicycle as an aerobic exercise machine.

    Science.gov (United States)

    Nagata, T; Okada, S; Makikawa, M

    2012-01-01

    The goal of this study is to maintain a continuous level of exercise intensity around the aerobic threshold (AT) during riding on an electric motor assisted bicycle using a new control system of electrical motor assistance which uses the efficient pedaling rate of popular bicycles. Five male subjects participated in the experiment, and the oxygen uptake was measured during cycling exercise using this new pedaling rate control system of electrical motor assistance, which could maintain the pedaling rate within a specific range, similar to that in previous type of electrically assisted bicycles. Results showed that this new pedaling rate control system at 65 rpm ensured continuous aerobic exercise intensity around the AT in two subjects, and this intensity level was higher than that observed in previous type. However, certain subjects were unable to maintain the expected exercise intensity because of their particular cycling preferences such as the pedaling rate. It is necessary to adjust the specific pedaling rate range of the electrical motor assist control according to the preferred pedaling rate, so that this system becomes applicable to anyone who want continuous aerobic exercise.

  10. Aerobic fitness and orthostatic tolerance: Evidence against an association

    Science.gov (United States)

    Ebert, Thomas J.

    1994-01-01

    This presentation will focus on only one side of the debate as to whether high levels of aerobic fitness have a deleterious effect on tolerance to gravitational stress. This issue was raised in the early 1970's as a result of two research publications. The first work investigated the carotid sinus baroreflex of humans with an airtight chamber that surrounded the head and neck. The steady-state reflex changes in blood pressure that were recorded 3 minutes after application of the head and neck stimuli, were attenuated in an athletic group compared to a sedentary group of volunteers. A second report in the NASA literature indicated that five endurance-trained runners were less tolerant to LBNP than five nonrunners. These early research findings have stimulated a considerable amount of interest that has lead to a growing number of research efforts seeking an association between aerobic fitness and orthostatic tolerance in humans. I will briefly review some of the more pertinent published research information which suggests that there is no relationship between aerobic fitness and orthostatic tolerance in humans.

  11. Echinacea Supplementation: Does it Really Improve Aerobic Fitness?

    Science.gov (United States)

    Baumann, Cory W.; Kwak, Dongmin

    2016-01-01

    [Purpose] Echinacea is an herbal supplement used by endurance athletes for its performance boosting properties. It is thought that Echinacea improves the blood’s oxygen carrying capacity by increasing production of erythropoietin (EPO), a glycoprotein that regulates red blood cell formation. Subsequently, these changes would lead to an overall improvement in maximal oxygen uptake (VO2max) and running economy (RE), two markers of aerobic fitness. The purpose of this review is to briefly discuss the physiological variables associated with distance running performance and how these variables are influenced by Echinacea supplementation. [Methods] To determine Echinacea’s ergogenic potential, human studies that used Echinacea in conjunction to analyzing the blood’s oxygen carrying capacity and/or aerobic fitness were assessed. [Results] Taken together, the majority of the published literature does not support the claim that Echinacea is a beneficial ergogenic aid. With the exception of one study, several independent groups have reported Echinacea supplementation does not increase EPO production, blood markers of oxygen transport, VO2max or RE in healthy untrained or trained subjects. [Conclusion] To date, the published literature does not support the use of Echinacea as an ergogenic aid to improve aerobic fitness in healthy untrained or trained subjects.

  12. Water aerobics in pregnancy: cardiovascular response, labor and neonatal outcomes

    Directory of Open Access Journals (Sweden)

    Braga Angelica F

    2008-11-01

    Full Text Available Abstract Background To evaluate the association between water aerobics, maternal cardiovascular capacity during pregnancy, labor and neonatal outcomes. Methods A randomized, controlled clinical trial was carried out in which 34 pregnant women were allocated to a water aerobics group and 37 to a control group. All women were submitted to submaximal ergometric tests on a treadmill at 19, 25 and 35 weeks of pregnancy and were followed up until delivery. Oxygen consumption (VO2 max, cardiac output (CO, physical fitness, skin temperature, data on labor and delivery, and neonate outcomes were evaluated. Frequency distributions of the baseline variables of both groups were initially performed and then analysis of the outcomes was carried out. Categorical data were compared using the chi-square test, and numerical using Student's t or Mann-Whitney tests. Wilk's Lambda or Friedman's analysis of repeat measurements were applied for comparison of physical capacity, cardiovascular outcomes and maternal temperature. Results VO2 max and physical fitness were higher in both groups in the second trimester, returning to basal levels in the third trimester. In both groups, CO increased as pregnancy progressed and peak exercise temperature was higher than resting temperature, increasing further after five minutes of recovery and remaining at this level until 15 minutes after exercise completion. There was no difference between the two groups regarding duration (457.9 ± SD 249.6 vs 428.9 ± SD 203.2 minutes or type of delivery. Labor analgesia was requested by significantly fewer women in the water aerobics group (27% vs 65%; RR = 0.42 95%CI 0.23–0.77. Neonatal results were similar in both groups. Conclusion The regular practice of moderate water aerobics by sedentary and low risk pregnant women was not detrimental to the health of the mother or the child. There was no influence on maternal cardiovascular capacity, duration of labor or type of delivery; however

  13. Evaluation of the petrifilm aerobic count plate for enumeration of aerobic marine bacteria from seawater and Caulerpa lentillifera.

    Science.gov (United States)

    Kudaka, Jun; Horii, Toru; Tamanaha, Koji; Itokazu, Kiyomasa; Nakamura, Masaji; Taira, Katsuya; Nidaira, Minoru; Okano, Sho; Kitahara, Akio

    2010-08-01

    The enumeration and evaluation of the activity of marine bacteria are important in the food industry. However, detection of marine bacteria in seawater or seafood has not been easy. The Petrifilm aerobic count plate (ACP) is a ready-to-use alternative to the traditional enumeration media used for bacteria associated with food. The purpose of this study was to evaluate the usefulness of a simple detection and enumeration method utilizing the Petrifilm ACP for enumeration of aerobic marine bacteria from seawater and an edible seaweed, Caulerpa lentillifera. The efficiency of enumeration of total aerobic marine bacteria on Petrifilm ACP was compared with that using the spread plate method on marine agar with 80 seawater and 64 C. lentillifera samples. With sterile seawater as the diluent, a close correlation was observed between the method utilizing Petrifilm ACP and that utilizing the conventional marine agar (r=0.98 for seawater and 0.91 for C. lentillifera). The Petrifilm ACP method was simpler and less time-consuming than the conventional method. These results indicate that Petrifilm ACP is a suitable alternative to conventional marine agar for enumeration of marine microorganisms in seawater and C. lentillifera samples.

  14. Comparison of membrane fouling during short-term filtration of aerobic granular sludge and activated sludge

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Aerobic granular sludge was cultivated adopting internal-circulate sequencing batch airlift reactor. The contradistinctive experiment about short-term membrane fouling between aerobic granular sludge system and activated sludge system were investigated. The membrane foulants was also characterized by Fourier Transform Infrared (FTIR) spectroscopy technique. The results showed that the aerobic granular sludge had excellent denitrification ability; the removal efficiency of TN could reach 90%. The aerobic granular sludge could alleviate membrane fouling effectively. The steady membrane flux of aerobic granular sludge was twice as much as that of activated sludge system. In addition, it was found that the aerobic granular sludge could result in severe membrane pore-blocking, however, the activated sludge could cause severe cake fouling. The major components of the foulants were identified as comprising of proteins and polysaccharide materials.

  15. Aerobic fitness is associated with greater hippocampal cerebral blood flow in children

    Directory of Open Access Journals (Sweden)

    Laura Chaddock-Heyman

    2016-08-01

    Full Text Available The present study is the first to investigate whether cerebral blood flow in the hippocampus relates to aerobic fitness in children. In particular, we used arterial spin labeling (ASL perfusion MRI to provide a quantitative measure of blood flow in the hippocampus in 73 7- to 9-year-old preadolescent children. Indeed, aerobic fitness was found to relate to greater perfusion in the hippocampus, independent of age, sex, and hippocampal volume. Such results suggest improved microcirculation and cerebral vasculature in preadolescent children with higher levels of aerobic fitness. Further, aerobic fitness may influence how the brain regulates its metabolic demands via blood flow in a region of the brain important for learning and memory. To add specificity to the relationship of fitness to the hippocampus, we demonstrate no significant association between aerobic fitness and cerebral blood flow in the brainstem. Our results reinforce the importance of aerobic fitness during a critical period of child development.

  16. The utilization of solar energy by non-phototrophic microorganisms through semiconducting minerals%半导体矿物介导非光合微生物利用光电子新途径

    Institute of Scientific and Technical Information of China (English)

    鲁安怀; 李艳; 王鑫; 丁竑瑞; 曾翠平; 郝瑞霞; 王长秋

    2013-01-01

    Phototropy and chemotrophy microorganisms compose the whole microbe world. As non-phototrophic microorganisms are excluded from phototrophy due to the lack of photo-tropic system. Here we introduce a novel pathway of microorganism energy utilization. The non-phototrophic microorganisms could get solar energy through semiconducting mineral photocatalysis. In simulated system, under simulated solar light semiconducting minerals, such as metal oxides and metal sulfides, generated photo electrons which could be used by non-phototrophic microorganisms to support their metabolisms. The growth of microorganism was closely related to photon quantity and energy and the microorganism growth and mineral light absorption spectra were fitted well under different light wavelengths. The overall energy efficiency from photon to biomass was 0.13%o to 1.90%o. Further studies revealed that in natural soil systems, semiconducting mineral photocatalysis could influence the microbial population. This study provided the evidence to reveal a novel but long existed pathway in which the semiconducting mineral photocatalysis could stimulate the non-phototrophic microorganism metabolisms.%自然界中微生物按其能量代谢途径主要分为两种:光能营养微生物和化能营养微生物.化能营养微生物作为非光能营养微生物长期被排除在以日光为能量来源的能量利用途径之外.本文介绍了一种新的微生物能量利用途径,即非光能营养微生物通过半导体矿物光催化作用来利用太阳能进行生长.实验室模拟体系中,金属氧化物、金属硫化物等天然半导体矿物在模拟日光激发下产生的光电子促进了化能自养与异养微生物的生长.研究结果表明微生物的生长与光子能量和光子数量密切相关,同时不同波长光辐照下的微生物生长情况与矿物的光吸收谱相吻合.这一能量利用途径的光能-生物能转化效率为0.13‰-1.90‰.在含有天然半导体

  17. Aerobic capacity and its relationship with parameters of health-related fitness in schoolchildren

    OpenAIRE

    Guillamón,Andrés Rosa; García-Cantó, Eliseo; Pérez Soto, Juan José; Rodríguez García, Pedro Luís

    2015-01-01

    Background and objective: The aim of this study was to analyze the relationship between aerobic capacity and other parameters determining fitness in primary school. Methods: A cross-sectional descriptive study, 298 schoolchildren (139 males and 159 females) aged 8-12. Body composition (weight and height) and physical fitness (capacity, motor aerobic and musculoskeletal) was assessed by ALPHA-Fitness battery. Aerobic capacity and body mass index (under/normal-weight and overweight/obesity) wer...

  18. Gene expression centroids that link with low intrinsic aerobic exercise capacity and complex disease risk

    OpenAIRE

    Kivelä, Riikka; Silvennoinen, Mika; Lehti, Maarit; Rinnankoski-Tuikka,, Rita; Purhonen, Tatja; Ketola, Tarmo; Pullinen, Katri; Vuento, Meri; Mutanen, Niina; Maureen A Sartor; Reunanen, Hilkka; Koch, Lauren G.; Britton, Steven L.; Kainulainen, Heikki

    2010-01-01

    A strong link exists between low aerobic exercise capacity and complex metabolic diseases. To probe this linkage, we utilized rat models of low and high intrinsic aerobic endurance running capacity that differ also in the risk for metabolic syndrome. We investigated in skeletal muscle gene-phenotype relationships that connect aerobic endurance capacity with metabolic disease risk factors. The study compared 12 high capacity runners (HCRs) and 12 low capacity runners (LCRs) from generation 18 ...

  19. Characteristics of aerobic granules grown on glucose a sequential batch shaking reactor

    Institute of Scientific and Technical Information of China (English)

    CAI Chun-guang; ZHU Nan-wen; LIU Jun-shen; WANG Zhen-peng; CAI Wei-min

    2004-01-01

    Aerobic heterotrophic granular sludge was cultivated in a sequencing batch shaking reactor(SBSR) in which a synthetic wastewater containing glucose as carbon source was fed. The characteristics of the aerobic granules were investigated. Compared with the conventional activated sludge flocs, the aerobic granules exhibit excellent physical characteristics in terms of settleability, size, shape, biomass density, and physical strength.Scanning electron micrographs revealed that in mature granules little filamentous bacteria could be found, rodshaped and coccoid bacteria were the dominant microorganisms.

  20. Acclimation of aerobic-activated sludge degrading benzene derivatives and co-metabolic degradation activities of trichloroethylene by benzene derivative-grown aerobic sludge.

    Science.gov (United States)

    Wang, Shizong; Yang, Qi; Bai, Zhiyong; Wang, Shidong; Wang, Yeyao; Nowak, Karolina M

    2015-01-01

    The acclimation of aerobic-activated sludge for degradation of benzene derivatives was investigated in batch experiments. Phenol, benzoic acid, toluene, aniline and chlorobenzene were concurrently added to five different bioreactors which contained the aerobic-activated sludge. After the acclimation process ended, the acclimated phenol-, benzoic acid-, toluene-, aniline- and chlorobenzene-grown aerobic-activated sludge were used to explore the co-metabolic degradation activities of trichloroethylene (TCE). Monod equation was employed to simulate the kinetics of co-metabolic degradation of TCE by benzene derivative-grown sludge. At the end of experiments, the mixed microbial communities grown under different conditions were identified. The results showed that the acclimation periods of microorganisms for different benzene derivatives varied. The maximum degradation rates of TCE for phenol-, benzoic acid-, toluene-, aniline- and chlorobenzene-grown aerobic sludge were 0.020, 0.017, 0.016, 0.0089 and 0.0047 mg g SS(-1) h(-1), respectively. The kinetic of TCE degradation in the absence of benzene derivative followed Monod equation well. Also, eight phyla were observed in the acclimated benzene derivative-grown aerobic sludge. Each of benzene derivative-grown aerobic sludge had different microbial community composition. This study can hopefully add new knowledge to the area of TCE co-metabolic by mixed microbial communities, and further the understanding on the function and applicability of aerobic-activated sludge.

  1. A single aerobic exercise session accelerates movement execution but not central processing.

    Science.gov (United States)

    Beyer, Kit B; Sage, Michael D; Staines, W Richard; Middleton, Laura E; McIlroy, William E

    2017-03-27

    Previous research has demonstrated that aerobic exercise has disparate effects on speed of processing and movement execution. In simple and choice reaction tasks, aerobic exercise appears to increase speed of movement execution while speed of processing is unaffected. In the flanker task, aerobic exercise has been shown to reduce response time on incongruent trials more than congruent trials, purportedly reflecting a selective influence on speed of processing related to cognitive control. However, it is unclear how changes in speed of processing and movement execution contribute to these exercise-induced changes in response time during the flanker task. This study examined how a single session of aerobic exercise influences speed of processing and movement execution during a flanker task using electromyography to partition response time into reaction time and movement time, respectively. Movement time decreased during aerobic exercise regardless of flanker congruence but returned to pre-exercise levels immediately after exercise. Reaction time during incongruent flanker trials decreased over time in both an aerobic exercise and non-exercise control condition indicating it was not specifically influenced by exercise. This disparate influence of aerobic exercise on movement time and reaction time indicates the importance of partitioning response time when examining the influence of aerobic exercise on speed of processing. The decrease in reaction time over time independent of aerobic exercise indicates that interpreting pre-to-post exercise changes in behavior requires caution.

  2. Removal of Pesticides and Inorganic Contaminants in Anaerobic and Aerobic Biological Contactors

    Science.gov (United States)

    This presentation contains data on the removal of pesticides (acetochlor, clethodim, dicrotophos), ammonia, nitrate, bromate and perchlorate through aerobic and anaerobic biological treatment processes.

  3. STUDY OF AEROBIC AND ANAEROBIC BACTERIA IN CHRONIC SUPPURATIVE OTITIS MEDIA

    Directory of Open Access Journals (Sweden)

    Satyanarayana

    2015-04-01

    Full Text Available One hundred six patients with clinical diagnosis of CSOM were investigated bacteriologically using appropriate aerobic and anaerobic techniques. Positive cultures were obtained in 100 specimens. Aerobic bacteria alone were present in 51%, anaerobic bacteria alone in 10% and a combination of both in 34% of aural swabs . The anaerobes isolated were Bacteroides 30%, Peptostreptococci 26%, followed by others. Aerobic bacteriology showed the predominance of Pseudomonas 30.4% followed by Staphylococcus aureus 21.4%. Metronidazole was found to be most effective (87% drug aga inst anaerobes and Amikacin (98% against aerobes.

  4. Terephthalic acid wastewater treatment by using two-stage aerobic process

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Based on the tests between anoxic and aerobic process, the two-stage aerobic process with a biological selector was chosen to treat terephthalic acid wastewater (PTA). By adopting the two- stage aerobic process, the CODCr in PTA wastewater could be reduced from 4000-6000 mg/L to below 100 mg/L; the COD loading in the first aerobic tank could reach 7.0-8.0 kgCODCr/(m3.d) and that of the second stage was from 0.2 to 0.4 kgCODCr/(m3.d). Further researches on the kinetics of substrate degradation were carried out.

  5. Effects of Aerobic Exercise on Anxiety Disorders: A Systematic Review.

    Science.gov (United States)

    de Souza Moura, Antonio Marcos; Lamego, Murilo Khede; Paes, Flávia; Ferreira Rocha, Nuno Barbosa; Simoes-Silva, Vitor; Rocha, Susana Almeida; de Sá Filho, Alberto Souza; Rimes, Ridson; Manochio, João; Budde, Henning; Wegner, Mirko; Mura, Gioia; Arias-Carrión, Oscar; Yuan, Ti-Fei; Nardi, Antonio Egidio; Machado, Sergio

    2015-01-01

    Anxiety disorders are the most common psychiatric disorders observed currently. It is a normal adaptive response to stress that allows coping with adverse situations. Nevertheless, when anxiety becomes excessive or disproportional in relation to the situation that evokes it or when there is not any special object directed at it, such as an irrational dread of routine stimuli, it becomes a disabling disorder and is considered to be pathological. The traditional treatment used is medication and cognitive behavioral psychotherapy, however, last years the practice of physical exercise, specifically aerobic exercise, has been investigated as a new non-pharmacological therapy for anxiety disorders. Thus, the aim of this article was to provide information on research results and key chains related to the therapeutic effects of aerobic exercise compared with other types of interventions to treat anxiety, which may become a useful clinical application in a near future. Researches have shown the effectiveness of alternative treatments, such as physical exercise, minimizing high financial costs and minimizing side effects. The sample analyzed, 66.8% was composed of women and 80% with severity of symptoms anxiety as moderate to severe. The data analyzed in this review allows us to claim that alternative therapies like exercise are effective in controlling and reducing symptoms, as 91% of anxiety disorders surveys have shown effective results in treating. However, there is still disagreement regarding the effect of exercise compared to the use of antidepressant symptoms and cognitive function in anxiety, this suggests that there is no consensus on the correct intensity of aerobic exercise as to achieve the best dose-response, with intensities high to moderate or moderate to mild.

  6. Cognitive enhancement by transcranial laser stimulation and acute aerobic exercise.

    Science.gov (United States)

    Hwang, Jungyun; Castelli, Darla M; Gonzalez-Lima, F

    2016-08-01

    This is the first randomized, controlled study comparing the cognitive effects of transcranial laser stimulation and acute aerobic exercise on the same cognitive tasks. We examined whether transcranial infrared laser stimulation of the prefrontal cortex, acute high-intensity aerobic exercise, or the combination may enhance performance in sustained attention and working memory tasks. Sixty healthy young adults were randomly assigned to one of the following four treatments: (1) low-level laser therapy (LLLT) with infrared laser to two forehead sites while seated (total 8 min, 1064 nm continuous wave, 250 mW/cm(2), 60 J/cm(2) per site of 13.6 cm(2)); (2) acute exercise (EX) of high-intensity (total 20 min, with 10-min treadmill running at 85-90 % VO2max); (3) combined treatment (LLLT + EX); or (4) sham control (CON). Participants were tested for prefrontal measures of sustained attention with the psychomotor vigilance task (PVT) and working memory with the delayed match-to-sample task (DMS) before and after the treatments. As compared to CON, both LLLT and EX reduced reaction time in the PVT [F(1.56) = 4.134, p = 0.01, η (2)  = 0.181] and increased the number of correct responses in the DMS [F(1.56) = 4.690, p = 0.005, η (2)  = 0.201], demonstrating a significant enhancing effect of LLLT and EX on cognitive performance. LLLT + EX effects were similar but showed no significantly greater improvement on PVT and DMS than LLLT or EX alone. The transcranial infrared laser stimulation and acute aerobic exercise treatments were similarly effective for cognitive enhancement, suggesting that they augment prefrontal cognitive functions similarly.

  7. Degradation of acid orange 7 in an aerobic biofilm.

    Science.gov (United States)

    Coughlin, Michael F; Kinkle, Brian K; Bishop, Paul L

    2002-01-01

    A stable microbial biofilm community capable of completely mineralizing the azo dye acid orange 7 (AO7) was established in a laboratory scale rotating drum bioreactor (RDBR) using waste liquor from a sewage treatment plant. A broad range of environmental conditions including pH (5.8-8.2), nitrification (0.0-4.0 mM nitrite), and aeration (0.2-6.2 mg O2 l(-1)) were evaluated for their effects on the biodegradation of AO7. Furthermore the biofilm maintained its biodegradative ability for over a year while the effects of these environmental conditions were evaluated. Reduction of the azo bond followed by degradation of the resulting aromatic amine appears to be the mechanism by which this dye is biodegraded. Complete loss of color, sulfanilic acid, and chemical oxygen demand (COD) indicate that AO7 is mineralized. To our knowledge this is the first reported occurrence of a sulfonated phenylazonaphthol dye being completely mineralized under aerobic conditions. Two bacterial strains (ICX and SAD4i) originally isolated from the RDBR were able to mineralize, in co-culture, up to 90% of added AO7. During mineralization of AO7, strain ICX reduces the azo bond under aerobic conditions and consumes the resulting cleavage product 1-amino-2-naphthol. Strain SAD4i consumes the other cleavage product, sulfanilic acid. The ability of the RDBR biofilm to aerobically mineralize an azo dye without exogenous carbon and nitrogen sources suggests that this approach could be used to remediate industrial wastewater contaminated with spent dye.

  8. A dual-species co-cultivation system to study the interactions between Roseobacters and dinoflagellates.

    Science.gov (United States)

    Wang, Hui; Tomasch, Jürgen; Jarek, Michael; Wagner-Döbler, Irene

    2014-01-01

    Some microalgae in nature live in symbiosis with microorganisms that can enhance or inhibit growth, thus influencing the dynamics of phytoplankton blooms. In spite of the great ecological importance of these interactions, very few defined laboratory systems are available to study them in detail. Here we present a co-cultivation system consisting of the toxic phototrophic dinoflagellate Prorocentrum minimum and the photoheterotrophic alphaproteobacterium Dinoroseobacter shibae. In a mineral medium lacking a carbon source, vitamins for the bacterium and the essential vitamin B12 for the dinoflagellate, growth dynamics reproducibly went from a mutualistic phase, where both algae and bacteria grow, to a pathogenic phase, where the algae are killed by the bacteria. The data show a "Jekyll and Hyde" lifestyle that had been proposed but not previously demonstrated. We used RNAseq and microarray analysis to determine which genes of D. shibae are transcribed and differentially expressed in a light dependent way at an early time-point of the co-culture when the bacterium grows very slowly. Enrichment of bacterial mRNA for transcriptome analysis was optimized, but none of the available methods proved capable of removing dinoflagellate ribosomal RNA completely. RNAseq showed that a phasin encoding gene (phaP1 ) which is part of the polyhydroxyalkanoate (PHA) metabolism operon represented approximately 10% of all transcripts. Five genes for aerobic anoxygenic photosynthesis were down-regulated in the light, indicating that the photosynthesis apparatus was functional. A betaine-choline-carnitine-transporter (BCCT) that may be used for dimethylsulfoniopropionate (DMSP) uptake was the highest up-regulated gene in the light. The data suggest that at this early mutualistic phase of the symbiosis, PHA degradation might be the main carbon and energy source of D. shibae, supplemented in the light by degradation of DMSP and aerobic anoxygenic photosynthesis.

  9. Degradation of toxaphene in water during anaerobic and aerobic conditions.

    Science.gov (United States)

    LacayoR, M; van Bavel, B; Mattiasson, B

    2004-08-01

    The degradation of technical toxaphene in water with two kinds of bioreactors operating in sequence was studied. One packed bed reactor was filled with Poraver (foam glass particles) running at anaerobic conditions and one suspended carrier biofilm reactor working aerobically. Chemical oxygen demand (COD), chloride, sulphate, pH, dissolved oxygen, total toxaphene and specific toxaphene isomers were measured. After 6 weeks approx. 87% of the total toxaphene was degraded reaching 98% by week 39. The majority of the conversion took place in the anaerobic reactor. The concentrations of toxaphene isomers with more chlorine substituents decreased more rapidly than for isomers with less chlorine substituents.

  10. Aerobic fitness related to cardiovascular risk factors in young children

    DEFF Research Database (Denmark)

    Dencker, Magnus; Thorsson, Ola; Karlsson, Magnus K

    2012-01-01

    Low aerobic fitness (maximum oxygen uptake (VO(2PEAK))) is predictive for poor health in adults. In a cross-sectional study, we assessed if VO(2PEAK) is related to a composite risk factor score for cardiovascular disease (CVD) in 243 children (136 boys and 107 girls) aged 8 to 11 years. VO(2PEAK......) was assessed by indirect calorimetry during a maximal exercise test and scaled by body mass (milliliters per minute per kilogram). Total body fat mass (TBF) and abdominal fat mass (AFM) were measured by Dual-energy X-ray absorptiometry. Total body fat was expressed as a percentage of total body mass (BF...

  11. Degradation of alkenones by aerobic heterotrophic bacteria: Selective or not ?

    Digital Repository Service at National Institute of Oceanography (India)

    Rontani, J-F.; Harji, R.; Guasco, S.; Prahl, F.G.; Volkman, J.K.; Bhosle, N.B.; Bonin, P.

    of alkenones by aerobic heterotrophic bacteria: selective or not? Jean-François Rontani a *, Ranjita Harji a,b , Sophie Guasco a , Fredrick G. Prahl c , John K. Volkman d , Narayan B. Bhosle b , Patricia Bonin a a Laboratoire de Microbiologie de..., Corvallis, OR 97331-5503, US. d CSIRO Marine and Atmospheric Research, GPO Box 1538, Hobart, Tasmania 7001, Australia * Corresponding author. Tel.: +33-4-91-82-96-51; fax: +33-4-91-82-96-41. E-mail address: jean-francois.rontani@com.univmed.fr (J...

  12. Aerobic granulation of pure bacterial strain Bacillus thuringiensis

    Institute of Scientific and Technical Information of China (English)

    Sunil S ADAV; Duu-Jong LEE

    2008-01-01

    The objective of this study is to cultivate aer-obic granules by pure bacterial strain, Bacillus thuringien-sis, in a sequencing batch reactor. Stable granules sized 2.0-2.2 mm were formed in the reactor after a five-week cultivation. These granules exhibited excellent settling attributes, and degraded phenol at rates of 1.49 and concentration, respectively. Confocal laser scanning microscopic test results show that Bacillus thuringiensis was distributed over the initial small aggregates, and the outer edge of the granule was away from the core regime in the following stage.

  13. Criterion Related Validity of Karate Specific Aerobic Test (KSAT

    Directory of Open Access Journals (Sweden)

    Chaabene

    2015-09-01

    Full Text Available Background Karate is one the most popular combat sports in the world. Physical fitness assessment on a regular manner is important for monitoring the effectiveness of the training program and the readiness of karatekas to compete. Objectives The aim of this research was to examine the criterion related to validity of the karate specific aerobic test (KSAT as an indicator of aerobic level of karate practitioners. Patients and Methods Cardiorespiratory responses, aerobic performance level through both treadmill laboratory test and YoYo intermittent recovery test level 1 (YoYoIRTL1 as well as time to exhaustion in the KSAT test (TE’KSAT were determined in a total of fifteen healthy international karatekas (i.e. karate practitioners (means ± SD: age: 22.2 ± 4.3 years; height: 176.4 ± 7.5 cm; body mass: 70.3 ± 9.7 kg and body fat: 13.2 ± 6%. Results Peak heart rate obtained from KSAT represented ~99% of maximal heart rate registered during the treadmill test showing that KSAT imposes high physiological demands. There was no significant correlation between KSAT’s TE and relative (mL/min kg treadmill maximal oxygen uptake (r = 0.14; P = 0.69; [small]. On the other hand, there was a significant relationship between KSAT’s TE and the velocity associated with VO2max (vVO2max (r = 0.67; P = 0.03; [large] as well as the velocity at VO2 corresponding to the second ventilatory threshold (vVO2 VAT (r = 0.64; P = 0.04; [large]. Moreover, significant relationship was found between TE’s KSAT and both the total distance covered and parameters of intermittent endurance measured through YoYoIRTL1. Conclusions The KSAT has not proved to have indirect criterion related validity as no significant correlations have been found between TE’s KSAT and treadmill VO2max. Nevertheless, as correlated to other aerobic fitness variables, KSAT can be considered as an indicator of karate specific endurance. The establishment of the criterion related validity of the

  14. Influence of inorganic salt on aerobic biodegradability of dyestuffs

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    this paper, the influence of inorganic salt on aerobic biodegradability of dyestuffs was studied by means of semicontinuous activated sludge method. It was found that: biodegradability of dyestuffs would decrease with the increase of the concentration of NaCl; however, biodegradability in the condition of NaCl = 30 g/L was better than that in the condition of NaCl =15 g/L; in the three NaCl conditions, biodegradability of tasted dyestuffs followed the following order: NaCl= 0 g/L > NaCl= 30g/L>NaCl= 15 g/L.

  15. Improved Aerobic Colony Count Technique for Hydrophobic Grid Membrane Filters

    OpenAIRE

    Parrington, Lorna J.; Sharpe, Anthony N.; Peterkin, Pearl I.

    1993-01-01

    The AOAC International official action procedure for performing aerobic colony counts on hydrophobic grid membrane filters (HGMFs) uses Trypticase soy-fast green FCF agar (FGA) incubated for 48 h. Microbial growths are various shades of green on a pale green background, which can cause problems for automated as well as manual counting. HGMFs which had been incubated 24 or 48 h at 35°C on Trypticase soy agar were flooded underneath with 1 to 2 ml of 0.1% triphenyltetrazolium chloride (TTC) sol...

  16. Electron beam/biological processing of anaerobic and aerobic sludge

    Science.gov (United States)

    Čuba, V.; Pospíšil, M.; Múčka, V.; Jeníček, P.; Dohányos, M.; Zábranská, J.

    2003-01-01

    Besides common chemical and biological methods, the radiation technology is a promising way of sludge treatment. The paper describes possibilities of combined accelerated electrons/biological processing of both anaerobic and aerobic sludge. Besides one-shot experiments, experimental reactors for the simulation of anaerobic processes have been used. Main effort has been aimed to decrease organic compounds concentration and overall volume of solids, to improve some physico-chemical parameters of sludge, to validate hygienisation effects of the ionising radiation, and in the case of anaerobic sludge, to increase the volume of the produced biogas. Positive effects of the electron beam processing have been observed on all previously named parameters.

  17. Stimulating kinetic of aerobic reactions skilled athlete in sport dance

    Directory of Open Access Journals (Sweden)

    Lee Bo

    2010-10-01

    Full Text Available Changes speed of development of reaction of frequency of heart-throbs are appraised under act of the program of trainings facilities. Directions stimulation of the cardiorespiratory system of sportsmen are rotined. In research took part 2 homogeneous groups of sportsmen for 12 sportsmen (6 pair. It is set that the high-rate of development of reactions of aerobic power providing reflects reactive properties of the cardiorespiratory system and influences on efficiency of functional preparation on the whole. Possibilities of estimation of reactive properties of the cardiorespiratory system are rotined in the natural terms of training process.

  18. Bioremediation of textile azo dyes by aerobic bacterial consortium.

    Science.gov (United States)

    Senan, Resmi C; Abraham, T Emilia

    2004-08-01

    An aerobic bacterial consortium consisting of two isolated strains (BF1, BF2) and a strain of Pseudomonas putida (MTCC1194) was developed for the aerobic degradation of a mixture of textile azodyes and individual azodyes at alkaline pH (9-10.5) and salinity (0.9-3.68 g/l) at ambient temperature (28 +/- 2 degrees C). The degradation efficiency of the strains in different media (mineral media and in the Simulated textile effluent (STE)) and at different dye concentrations were studied. The presence of a H2O2 independent oxidase-laccase (26.5 IU/ml) was found in the culture filtrate of the organism BF2. The analysis of the degraded products by TLC and HPLC, after the microbial treatment of the dyes showed the absence of amines and the presence of low molecular weight oxidative degradation products. The enzymes present in the crude supernatant was found to be reusable for the dye degradation.

  19. Training intensities for aerobic exercise determined on untrained healthy men.

    Directory of Open Access Journals (Sweden)

    Miura,Mochiyoshi

    1995-04-01

    Full Text Available The purpose of this study was to determine the aerobic training intensity from the maximal and submaximal running exercise in 21 untrained adult men. To accomplish this, we evaluated the relationship between physiological (oxygen intake and heart rate and physical parameters (running speed of training intensity, and determined the training intensity at the submaximal exercise. Oxygen intake and heart rate were measured by a treadmill test. The maximal oxygen intake (VO2 max, and the aerobic threshold (AerT and anaerobic threshold (AT were measured to determine respiratory gas exchange. Running capacity was measured by a 12-min running and treadmill test. For the maximal exercise, there was a significant correlation (r = 0.88, P < 0.01 between VO2 max and 12-min running distance (speed. In addition, the oxygen intake and heart rate at AerT and AT in the submaximal exercise were linearly correlated with running speed. Three levels of training intensity at the submaximal exercise were termed: light, moderate, and heavy. Since AerT was the lower limit intensity and AT was the upper limit, we took the middle of their values as the moderate intensity. The end point for the determination of the training intensity at the submaximal exercise was estimated to be 85% VO2 max and 180 beats.min-1.

  20. Critical period of weed control in aerobic rice.

    Science.gov (United States)

    Anwar, M P; Juraimi, A S; Samedani, B; Puteh, A; Man, A

    2012-01-01

    Critical period of weed control is the foundation of integrated weed management and, hence, can be considered the first step to design weed control strategy. To determine critical period of weed control of aerobic rice, field trials were conducted during 2010/2011 at Universiti Putra Malaysia. A quantitative series of treatments comprising two components, (a) increasing duration of weed interference and (b) increasing length of weed-free period, were imposed. Critical period was determined through Logistic and Gompertz equations. Critical period varied between seasons; in main season, it started earlier and lasted longer, as compared to off-season. The onset of the critical period was found relatively stable between seasons, while the end was more variable. Critical period was determined as 7-49 days after seeding in off-season and 7-53 days in main season to achieve 95% of weed-free yield, and 23-40 days in off-season and 21-43 days in main season to achieve 90% of weed-free yield. Since 5% yield loss level is not practical from economic view point, a 10% yield loss may be considered excellent from economic view point. Therefore, aerobic rice should be kept weed-free during 21-43 days for better yield and higher economic return.

  1. Critical Period of Weed Control in Aerobic Rice

    Directory of Open Access Journals (Sweden)

    M. P. Anwar

    2012-01-01

    Full Text Available Critical period of weed control is the foundation of integrated weed management and, hence, can be considered the first step to design weed control strategy. To determine critical period of weed control of aerobic rice, field trials were conducted during 2010/2011 at Universiti Putra Malaysia. A quantitative series of treatments comprising two components, (a increasing duration of weed interference and (b increasing length of weed-free period, were imposed. Critical period was determined through Logistic and Gompertz equations. Critical period varied between seasons; in main season, it started earlier and lasted longer, as compared to off-season. The onset of the critical period was found relatively stable between seasons, while the end was more variable. Critical period was determined as 7–49 days after seeding in off-season and 7–53 days in main season to achieve 95% of weed-free yield, and 23–40 days in off-season and 21–43 days in main season to achieve 90% of weed-free yield. Since 5% yield loss level is not practical from economic view point, a 10% yield loss may be considered excellent from economic view point. Therefore, aerobic rice should be kept weed-free during 21–43 days for better yield and higher economic return.

  2. Group aquatic aerobic exercise for children with disabilities.

    Science.gov (United States)

    Fragala-Pinkham, Maria; Haley, Stephen M; O'Neil, Margaret E

    2008-11-01

    The effectiveness and safety of a group aquatic aerobic exercise program on cardiorespiratory endurance for children with disabilities was examined using an A-B study design. Sixteen children (11 males, five females) age range 6 to 11 years (mean age 9y 7mo [SD 1y 4mo]) participated in this twice-per-week program lasting 14 weeks. The children's diagnoses included autism spectrum disorder, myelomeningocele, cerebral palsy, or other developmental disability. More than half of the children ambulated independently without aids. Children swam laps and participated in relay races and games with a focus of maintaining a defined target heart rate zone. The strengthening component consisted of exercises using bar bells, aquatic noodles, and water resistance. The following outcomes were measured: half-mile walk/run, isometric muscle strength, timed floor to stand 3-meter test, and motor skills. Complaints of pain or injury were systematically collected. Significant improvements in the half-mile walk/run were observed, but not for secondary outcomes of strength or motor skills. The mean program attendance was 80%, and no injury was reported. Children with disabilities may improve their cardiorespiratory endurance after a group aquatic aerobic exercise program with a high adult:child ratio and specific goals to maintain training heart rates.

  3. Biodegradability of selected highly energetic pollutants under aerobic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Jones, A.M.; Greer, C.W.; Hawari, J. [National Research Council of Canada, Montreal, Quebec (Canada). Biotechnology Research Inst.; Ampleman, G. [Defence Research Establishment Valcartier, Courcelette, Quebec (Canada). Div. des Materiaux Energetiques; Lavigne, J. [Canadian Embassy, Washington, DC (United States)

    1995-12-31

    Laboratory studies were conducted to assess the biodegradation potential of four energetic compounds--1,3,5-trinitro-1,3,5-triazacyclohexane (RDX), 2,4,6-trinitrotoluene (TNT), glycidyl azide polymer (GAP), and nitrocellulose (NC)--under aerobic conditions. Soils contaminated with energetic compounds were screened for microorganisms able to degrade these compounds. Rhodococcus sp. strain A was enriched and purified from RDX-contaminated soil by its ability to use RDX as sole source of nitrogen. Using [{sup 14}C]-labeled RDX, its ability to mineralize RDX to CO{sub 2} in pure culture under aerobic conditions was verified. Bioaugmentation of RDX-contaminated soil with this bacterium enhanced the rate and extent of biodegradation. Although TNT is a more toxic and recalcitrant pollutant, concentration-dependent [{sup 14}C]TNT mineralization activity was detected in TNT-contaminated soil. A Pseudomonas sp., enriched from this soil, was able to extensively transform TNT to partially reduced amine metabolites in axenic liquid culture. In contrast to these isolates, which utilized RDX and TNT as sources of nitrogen, soil consortia developed from soils exhibiting [{sup 14}C]GAP and [{sup 14}C]NC mineralization activities used GAP and NC as sole carbon sources for growth.

  4. Immunological analysis of aerobic bioreactor bovine theileriosis vaccine.

    Directory of Open Access Journals (Sweden)

    Gholamreza Habibi

    2014-09-01

    Full Text Available In this study, the pilot production of aerobic bioreactor tropical theileriosis vaccine was optimized with the aim of immunological assays for further mass production.We have shown earlier the delayed type hypersensitivity (DTH assay could be used for evaluating the immunity and memory cells against specific Theileria antigen in vaccinated animals. In addition, TNF-α is the principle cytokine in modulating the cytotoxic activity of cytotoxic T-lymphocytes (CTL. Immunological analysis of the vaccine was performed by using two cell mediated immunity (CMI in vitro and in vivo DTH test (Theilerin and TNF-α assay.The results of immune responses of susceptible immunized cattle by bioreactor vaccine in comparison with conventional flask vaccine revealed a significant stimulation of immune cells by transcription of high level of TNF-α and positive reaction against Theileria antigen in Theilerin skin test (DTH.The equal immunological results achieved in both above mentioned vaccines verified the satisfactory immunity for aerobic bioreactor theileriosis vaccine for advance mass vaccination in the field on a large-scale.

  5. Aerobic and anaerobic incubation: Biological indexes of soil nitrogen availability

    Directory of Open Access Journals (Sweden)

    Kresović Mirjana M.

    2005-01-01

    Full Text Available Our researches have been made on brown forest soil that had been used in long-term experiments set up according to specified fertilization system for over 30 years. We have chosen those experiment variants in which quantities of nitrogen fertilizers were gradually increased. The soil samples taken from 0 cm to 30 cm depth were used to determine biological indexes of nitrogen availability (aerobic and anaerobic incubation. The same samples were also used for pot experiments with oat. Plant and soil parameters obtained in controlled conditions were used for determination of biological indexes reliability in measuring the soil nitrogen availability. On the grounds of correlation analysis, it can be concluded that biological index of nitrogen availability achieved by the anaerobic incubation (without substraction of the initial content of available nitrogen of the investigated brown forest soil is the reliable indicator of soil nitrogen availability. That is not the case with the aerobic incubation in which reliability has not been established.

  6. Enhanced aerobic sludge granulation with layered double hydroxide

    Directory of Open Access Journals (Sweden)

    Jizhi Zhou

    2014-06-01

    Full Text Available Aerobic granular sludge technology has been developed for the biochemical treatment of wastewater in the present study. A fast cultivation of aerobic granular sludge was realized in Sequencing Batch Reactor (SBR, where Mg-Al layered double hydroxide (LDH was used as a carrier for granules growth. In comparison, the sludge particle size with LDH addition was bigger than those without LDH, with more than 50% of compact granular sludge >1.4 mm in size. This indicatestheLDH improved the growth ofthegranular sludge. The frequency of LDH addition had little effect on the granule growth. Moreover, the formation of granules led to the low sludge volume index (SVI and high mixed liquid suspended solids (MLSS in SBR reactor. With the formation of granular sludge, more than 80% of COD was removed in SBR reactor. The high COD removal efficiency of wastewater was observed regardless of various COD loading strength. The results suggest that the growth of granular sludge with LDH as a carrier enhanced the treatment efficiency. Therefore, our results have provided a promising way to prepare the granular sludge for wastewater treatment.

  7. On Aerobic Exercise and Behavioral and Neural Plasticity

    Directory of Open Access Journals (Sweden)

    Caitlin Peplinski

    2012-11-01

    Full Text Available Aerobic exercise promotes rapid and profound alterations in the brain. Depending upon the pattern and duration of exercise, these changes in the brain may extend beyond traditional motor areas to regions and structures normally linked to learning, cognition, and emotion. Exercise-induced alterations may include changes in blood flow, hormone and growth factor release, receptor expression, angiogenesis, apoptosis, neurogenesis, and synaptogenesis. Together, we believe that these changes underlie elevations of mood and prompt the heightened behavioral plasticity commonly observed following adoption of a chronic exercise regimen. In the following paper, we will explore both the psychological and psychobiological literatures relating to exercise effects on brain in both human and non-human animals and will attempt to link plastic changes in these neural structures to modifications in learned behavior and emotional expression. In addition, we will explore the therapeutic potential of exercise given recent reports that aerobic exercise may serve as a neuroprotectant and can also slow cognitive decline during normal and pathological aging.

  8. Improved aerobic colony count technique for hydrophobic grid membrane filters.

    Science.gov (United States)

    Parrington, L J; Sharpe, A N; Peterkin, P I

    1993-09-01

    The AOAC International official action procedure for performing aerobic colony counts on hydrophobic grid membrane filters (HGMFs) uses Trypticase soy-fast green FCF agar (FGA) incubated for 48 h. Microbial growths are various shades of green on a pale green background, which can cause problems for automated as well as manual counting. HGMFs which had been incubated 24 or 48 h at 35 degrees C on Trypticase soy agar were flooded underneath with 1 to 2 ml of 0.1% triphenyltetrazolium chloride (TTC) solution by simply lifting one corner of the filter while it was still on the agar and adding the reagent. Microbial growths on HGMFs were counted after color had been allowed to develop for 15 min at room temperature. With representative foods, virtually all colonies stained pink to red. Automated electronic counts made by using the MI-100 HGMF Interpreter were easier and more reliable than control HGMF counts made by the AOAC International official action procedure. Manual counting was easier as well because of increased visibility of the microbial growths. Except in the case of dairy products, 24-h TTC counts did not differ significantly from 48-h FGA counts, whereas the FGA counts at 24 h were always significantly lower, indicating that for many food products the HGMF TTC flooding method permits aerobic colony counts to be made after 24 h.

  9. Fetal cardiotocography before and after water aerobics during pregnancy

    Directory of Open Access Journals (Sweden)

    Silveira Carla

    2010-08-01

    Full Text Available Abstract Objective To evaluate the effect of moderate aerobic physical activity in water on fetal cardiotocography patterns in sedentary pregnant women. Method In a non-randomized controlled trial, 133 previously sedentary pregnant women participated in multiple regular sessions of water aerobics in a heated swimming pool. Cardiotocography was performed for 20 minutes before and just after the oriented exercise. Cardiotocography patterns were analyzed pre- and post-exercise according to gestational age groups (24-27, 28-31, 32-35 and 36-40 weeks. Student's t and Wilcoxon, and McNemar tests were used, respectively, to analyze numerical and categorical variables. Results No significant variations were found between pre- and post-exercise values of fetal heart rate (FHR, number of fetal body movements (FM or accelerations (A, FM/A ratio or the presence of decelerations. Variability in FHR was significantly higher following exercise only in pregnancies of 24-27 weeks. Conclusions Moderate physical activity in water was not associated with any significant alterations in fetal cardiotocography patterns, which suggests no adverse effect on the fetus.

  10. Nitroglycerin degradation mediated by soil organic carbon under aerobic conditions.

    Science.gov (United States)

    Bordeleau, Geneviève; Martel, Richard; Bamba, Abraham N'Valoua; Blais, Jean-François; Ampleman, Guy; Thiboutot, Sonia

    2014-10-01

    The presence of nitroglycerin (NG) has been reported in shallow soils and pore water of several military training ranges. In this context, NG concentrations can be reduced through various natural attenuation processes, but these have not been thoroughly documented. This study aimed at investigating the role of soil organic matter (SOM) in the natural attenuation of NG, under aerobic conditions typical of shallow soils. The role of SOM in NG degradation has already been documented under anoxic conditions, and was attributed to SOM-mediated electron transfer involving different reducing agents. However, unsaturated soils are usually well-oxygenated, and it was not clear whether SOM could participate in NG degradation under these conditions. Our results from batch- and column-type experiments clearly demonstrate that in presence of dissolved organic matter (DOM) leached from a natural soil, partial NG degradation can be achieved. In presence of particulate organic matter (POM) from the same soil, complete NG degradation was achieved. Furthermore, POM caused rapid sorption of NG, which should result in NG retention in the organic matter-rich shallow horizons of the soil profile, thus promoting degradation. Based on degradation products, the reaction pathway appears to be reductive, in spite of the aerobic conditions. The relatively rapid reaction rates suggest that this process could significantly participate in the natural attenuation of NG, both on military training ranges and in contaminated soil at production facilities.

  11. Anaerobic Metabolism: Linkages to Trace Gases and Aerobic Processes

    Science.gov (United States)

    Megonigal, J. P.; Hines, M. E.; Visscher, P. T.

    2003-12-01

    Life evolved and flourished in the absence of molecular oxygen (O2). As the O2 content of the atmosphere rose to the present level of 21% beginning about two billion years ago, anaerobic metabolism was gradually supplanted by aerobic metabolism. Anaerobic environments have persisted on Earth despite the transformation to an oxidized state because of the combined influence of water and organic matter. Molecular oxygen diffuses about 104 times more slowly through water than air, and organic matter supports a large biotic O2 demand that consumes the supply faster than it is replaced by diffusion. Such conditions exist in wetlands, rivers, estuaries, coastal marine sediments, aquifers, anoxic water columns, sewage digesters, landfills, the intestinal tracts of animals, and the rumen of herbivores. Anaerobic microsites are also embedded in oxic environments such as upland soils and marine water columns. Appreciable rates of aerobic respiration are restricted to areas that are in direct contact with air or those inhabited by organisms that produce O2.Rising atmospheric O2 reduced the global area of anaerobic habitat, but enhanced the overall rate of anaerobic metabolism (at least on an area basis) by increasing the supply of electron donors and acceptors. Organic carbon production increased dramatically, as did oxidized forms of nitrogen, manganese, iron, sulfur, and many other elements. In contemporary anaerobic ecosystems, nearly all of the reducing power is derived from photosynthesis, and most of it eventually returns to O2, the most electronegative electron acceptor that is abundant. This photosynthetically driven redox gradient has been thoroughly exploited by aerobic and anaerobic microorganisms for metabolism. The same is true of hydrothermal vents (Tunnicliffe, 1992) and some deep subsurface environments ( Chapelle et al., 2002), where thermal energy is the ultimate source of the reducing power.Although anaerobic habitats are currently a small fraction of Earth

  12. Steady-state and transient-state analyses of aerobic fermentation in Saccharomyces kluyveri

    DEFF Research Database (Denmark)

    Møller, Kasper; Bro, Christoffer; Piskur, Jure

    2002-01-01

    Some yeasts, such as Saccharomyces cerevisiae, produce ethanol at fully aerobic conditions, whereas other yeasts, such as Kluyveromyces lactis, do not. In this study we investigated the occurrence of aerobic alcoholic fermentation in the petite-negative yeast Saccharomyces kluyveri that is only...

  13. Protective Role of Aerobic Exercise Against Cisplatin-Induced Nephrotoxicity in Rats

    OpenAIRE

    Zeynali; Nematbakhsh; Mojtahedi; Poorshahnazari; Talebi; Pezeshki; Mazaheri; Moslemi

    2015-01-01

    Background Cisplatin (CP) is a chemotherapy drug and nephrotoxicity is considered as its major side effect. Aerobic exercise is well known as an approach to reduce the side effects of many drugs. Objectives This study was designed to determine the protective role of aerobic exercise against CP-induced nephrotoxicity. Materials and Methods Thirty male Wistar rats were randomly divid...

  14. Is the effect of aerobic exercise on cognition a placebo effect?

    Directory of Open Access Journals (Sweden)

    Cary R Stothart

    Full Text Available A number of studies and meta-analyses conclude that aerobic fitness (walking interventions improve cognition. Such interventions typically compare improvements from these interventions to an active control group in which participants engage in non-aerobic activities (typically stretching and toning for an equivalent amount of time. However, in the absence of a double-blind design, the presence of an active control group does not necessarily control for placebo effects; participants might expect different amounts of improvement for the treatment and control interventions. We conducted a large survey to explore whether people expect greater cognitive benefits from an aerobic exercise intervention compared to a control intervention. If participants expect greater improvement following aerobic exercise, then the benefits of such interventions might be due in part to a placebo effect. In general, expectations did not differ between aerobic and non-aerobic interventions. If anything, some of the results suggest the opposite (e.g., respondents expected the control, non-aerobic intervention to yield bigger memory gains. These results provide the first evidence that cognitive improvements following aerobic fitness training are not due to differential expectations.

  15. Modeling of vapor intrusion from hydrocarbon-contaminated sources accounting for aerobic and anaerobic biodegradation.

    Science.gov (United States)

    Verginelli, Iason; Baciocchi, Renato

    2011-11-01

    A one-dimensional steady state vapor intrusion model including both anaerobic and oxygen-limited aerobic biodegradation was developed. The aerobic and anaerobic layer thickness are calculated by stoichiometrically coupling the reactive transport of vapors with oxygen transport and consumption. The model accounts for the different oxygen demand in the subsurface required to sustain the aerobic biodegradation of the compound(s) of concern and for the baseline soil oxygen respiration. In the case of anaerobic reaction under methanogenic conditions, the model accounts for the generation of methane which leads to a further oxygen demand, due to methane oxidation, in the aerobic zone. The model was solved analytically and applied, using representative parameter ranges and values, to identify under which site conditions the attenuation of hydrocarbons migrating into indoor environments is likely to be significant. Simulations were performed assuming a soil contaminated by toluene only, by a BTEX mixture, by Fresh Gasoline and by Weathered Gasoline. The obtained results have shown that for several site conditions oxygen concentration below the building is sufficient to sustain aerobic biodegradation. For these scenarios the aerobic biodegradation is the primary mechanism of attenuation, i.e. anaerobic contribution is negligible and a model accounting just for aerobic biodegradation can be used. On the contrary, in all cases where oxygen is not sufficient to sustain aerobic biodegradation alone (e.g. highly contaminated sources), anaerobic biodegradation can significantly contribute to the overall attenuation depending on the site specific conditions.

  16. Sweat Rates During Continuous and Interval Aerobic Exercise: Implications for NASA Multipurpose Crew Vehicle (MPCV) Missions

    Science.gov (United States)

    Ryder, Jeffrey W.; Scott, Jessica; Ploutz-Snyder, Robert; Ploutz-Snyder, Lori L.

    2016-01-01

    Aerobic deconditioning is one of the effects spaceflight. Impaired crewmember performance due to loss of aerobic conditioning is one of the risks identified for mitigation by the NASA Human Research Program. Missions longer than 8 days will involve exercise countermeasures including those aimed at preventing the loss of aerobic capacity. The NASA Multipurpose Crew Vehicle (MPCV) will be NASA's centerpiece architecture for human space exploration beyond low Earth orbit. Aerobic exercise within the small habitable volume of the MPCV is expected to challenge the ability of the environmental control systems, especially in terms of moisture control. Exercising humans contribute moisture to the environment by increased respiratory rate (exhaling air at 100% humidity) and sweat. Current acceptable values are based on theoretical models that rely on an "average" crew member working continuously at 75% of their aerobic capacity (Human Systems Integration Requirements Document). Evidence suggests that high intensity interval exercise for much shorter durations are equally effective or better in building and maintaining aerobic capacity. This investigation will examine sweat and respiratory rates for operationally relevant continuous and interval aerobic exercise protocols using a variety of different individuals. The results will directly inform what types of aerobic exercise countermeasures will be feasible to prescribe for crewmembers aboard the MPCV.

  17. Modeling of vapor intrusion from hydrocarbon-contaminated sources accounting for aerobic and anaerobic biodegradation

    Science.gov (United States)

    Verginelli, Iason; Baciocchi, Renato

    2011-11-01

    A one-dimensional steady state vapor intrusion model including both anaerobic and oxygen-limited aerobic biodegradation was developed. The aerobic and anaerobic layer thickness are calculated by stoichiometrically coupling the reactive transport of vapors with oxygen transport and consumption. The model accounts for the different oxygen demand in the subsurface required to sustain the aerobic biodegradation of the compound(s) of concern and for the baseline soil oxygen respiration. In the case of anaerobic reaction under methanogenic conditions, the model accounts for the generation of methane which leads to a further oxygen demand, due to methane oxidation, in the aerobic zone. The model was solved analytically and applied, using representative parameter ranges and values, to identify under which site conditions the attenuation of hydrocarbons migrating into indoor environments is likely to be significant. Simulations were performed assuming a soil contaminated by toluene only, by a BTEX mixture, by Fresh Gasoline and by Weathered Gasoline. The obtained results have shown that for several site conditions oxygen concentration below the building is sufficient to sustain aerobic biodegradation. For these scenarios the aerobic biodegradation is the primary mechanism of attenuation, i.e. anaerobic contribution is negligible and a model accounting just for aerobic biodegradation can be used. On the contrary, in all cases where oxygen is not sufficient to sustain aerobic biodegradation alone (e.g. highly contaminated sources), anaerobic biodegradation can significantly contribute to the overall attenuation depending on the site specific conditions.

  18. Aerobic Exercise Increases Peripheral and Hepatic Insulin Sensitivity in Sedentary Adolescents

    NARCIS (Netherlands)

    van der Heijden, Gert-Jan; Toffolo, Gianna; Manesso, Erica; Sauer, Pieter J. J.; Sunehag, Agneta L.

    2009-01-01

    Context: Data are limited on the effects of controlled aerobic exercise programs (without weight loss) on insulin sensitivity and glucose metabolism in children and adolescents. Objective: To determine whether a controlled aerobic exercise program (without weight loss) improves peripheral and hepati

  19. Aerobic capacity influences the spatial position of individuals within fish schools

    DEFF Research Database (Denmark)

    Killen, Shaun S.; Marras, Stefano; Steffensen, John Fleng;

    2012-01-01

    of juvenile mullet Liza aurata were filmed at three swim speeds in a swim tunnel, with one focal fish from each school then also measured for standard metabolic rate (SMR), maximal metabolic rate (MMR), aerobic scope (AS) and maximum aerobic swim speed. At faster speeds, fish with lower MMR and AS swam near...

  20. The impact of aerobic fitness on functioning in chronic back pain

    NARCIS (Netherlands)

    Wormgoor, Marjon; Indahl, Aage; Tulder, van Maurits; Kemper, Han

    2007-01-01

    Despite lack of convincing evidence that reduced aerobic fitness is associated with chronic back pain (CBP), exercise programs are regarded as being effective for persons with non-specific CBP. It is unsure whether gain in aerobic fitness following intervention is associated with functioning impro

  1. Degradation of TCE using sequential anaerobic biofilm and aerobic immobilized bed reactor

    Science.gov (United States)

    Chapatwala, Kirit D.; Babu, G. R. V.; Baresi, Larry; Trunzo, Richard M.

    1995-01-01

    Bacteria capable of degrading trichloroethylene (TCE) were isolated from contaminated wastewaters and soil sites. The aerobic cultures were identified as Pseudomonas aeruginosa (four species) and Pseudomonas fluorescens. The optimal conditions for the growth of aerobic cultures were determined. The minimal inhibitory concentration values of TCE for Pseudomonas sps. were also determined. The aerobic cells were immobilized in calcium alginate in the form of beads. Degradation of TCE by the anaerobic and dichloroethylene (DCE) by aerobic cultures was studied using dual reactors - anaerobic biofilm and aerobic immobilized bed reactor. The minimal mineral salt (MMS) medium saturated with TCE was pumped at the rate of 1 ml per hour into the anaerobic reactor. The MMS medium saturated with DCE and supplemented with xylenes and toluene (3 ppm each) was pumped at the rate of 1 ml per hour into the fluidized air-uplift-type reactor containing the immobilized aerobic cells. The concentrations of TCE and DCE and the metabolites formed during their degradation by the anaerobic and aerobic cultures were monitored by GC. The preliminary study suggests that the anaerobic and aerobic cultures of our isolates can degrade TCE and DCE.

  2. THE EFFECT OF SLEEP DEPRIVATION ON SERUM IGG RESPONSES TO AEROBIC ACTIVITY IN COLLEGE STUDENT ATHLETES

    Directory of Open Access Journals (Sweden)

    Saeed Jamshidi Far

    2014-11-01

    Full Text Available Background & Aims: Sleep is a restorative process for the immune system. There are many situations in which sleep is disturbed prior to an athletic event. However, the effect of sleep deprivation on immune indices in response to exercise remains unknown. The aim of this study was to investigate the effects of sleep deprivation on serum IgG responses to aerobic activity. Materials & Methods: In this quasi-experimental study, 10 male physical education students were voluntarily participated. Study was performed in two separate occasions; control and experimental within two weeks. In the control occasion, normal sleep and aerobic activity and in the experimental occasion, sleep deprivation and aerobic activity was applied. Aerobic activity was performed on bicycle ergometer for 30 minutes at intensity of 70 to 75 percent of maximum heart rate. Changes in serum IgG concentrations in pre-test, before and after aerobic activity in both occasions were analyzed by the two repeated measures ANOVA and dependent T-test using SPSS software. Results: The results showed that sleep deprivation not significantly effect on Serum IgG response to aerobic activity (p=0.130. Also, aerobic activity not significantly effect on Serum IgG concentration (p=0.357. But sleep deprivation caused a significantly increase in serum IgG concentration (p=0.035. Conclusion: No significant effect of sleep deprivation on serum IgG concentrations response to aerobic activity.

  3. Active Female Maximal and Anaerobic Threshold Cardiorespiratory Responses to Six Different Water Aerobics Exercises

    Science.gov (United States)

    Antunes, Amanda H.; Alberton, Cristine L.; Finatto, Paula; Pinto, Stephanie S.; Cadore, Eduardo L.; Zaffari, Paula; Kruel, Luiz F. M.

    2015-01-01

    Purpose: Maximal tests conducted on land are not suitable for the prescription of aquatic exercises, which makes it difficult to optimize the intensity of water aerobics classes. The aim of the present study was to evaluate the maximal and anaerobic threshold cardiorespiratory responses to 6 water aerobics exercises. Volunteers performed 3 of the…

  4. Aerobic and anaerobic exercise capacity in children with juvenile idiopathic arthritis

    NARCIS (Netherlands)

    van Brussel, Marco; Lelieveld, O T H M; van der Net, J; Engelbert, R H H; Helders, P J M; Takken, T

    2007-01-01

    Objective. To compare the aerobic and anaerobic exercise capacity of children with juvenile idiopathic arthritis (JIA) with healthy controls, to determine if there were differences based on disease onset type, and to examine the relationship between aerobic and anaerobic exercise capacity in childre

  5. Aerobic capacity reference data in 3816 healthy men and women 20-90 years

    DEFF Research Database (Denmark)

    Loe, Henrik; Rognmo, Øivind; Saltin, Bengt

    2013-01-01

    To provide a large reference material on aerobic fitness and exercise physiology data in a healthy population of Norwegian men and women aged 20-90 years.......To provide a large reference material on aerobic fitness and exercise physiology data in a healthy population of Norwegian men and women aged 20-90 years....

  6. Aerobic and anaerobic exercise capacity in adolescents with juvenile idiopathic arthritis

    NARCIS (Netherlands)

    Lelieveld, Otto; van Brussel, Marco; Takken, Tim; van Weert, Ellen; van Leeuwen, Miek A.; Armbrust, Wineke

    2007-01-01

    OBJECTIVE: To examine the aerobic and anaerobic exercise capacity in adolescents with juvenile idiopathic arthritis (JIA) compared with age- and sex-matched healthy individuals, and to assess associations between disease-related variables and aerobic and anaerobic exercise capacity. METHODS: Of 25 p

  7. Relation Between Aerobic Capacity and Walking Ability in Older Adults With a Lower-Limb Amputation

    NARCIS (Netherlands)

    Wezenberg, Daphne; van der Woude, Lucas H.; Faber, Willemijn X.; de Haan, Arnold; Houdijk, Han

    2013-01-01

    Objectives: To determine the relative aerobic load, walking speed, and walking economy of older adults with a lower-limb prosthesis, and to predict the effect of an increased aerobic capacity on their walking ability. Design: Cross-sectional. Setting: Human motion laboratory at a rehabilitation cent

  8. Effects of anaerobic digestion and aerobic treatment on gaseous emissions from dairy manure storages

    Science.gov (United States)

    Effects of anaerobic digestion and aerobic treatment on the reduction of gaseous emissions from dairy manure storages were evaluated in this study. Screened dairy manure containing 3.5% volatile solids (VS) was either anaerobically digested or aerobically treated prior to storage in air-tight vessel...

  9. RATES OF SULFATE REDUCTION AND THIOSULFATE CONSUMPTION IN A MARINE MICROBIAL MAT

    NARCIS (Netherlands)

    VISSCHER, PT; PRINS, RA; VANGEMERDEN, H

    1992-01-01

    The sulfur cycle in a microbial mat was studied by determining viable counts of sulfate-reducing bacteria, chemolithoautotrophic sulfur bacteria and anoxygenic phototrophic bacteria. All three functional groups of sulfur bacteria revealed a maximum population density in the uppermost 5 mm of the mat

  10. Comparative Genomics of Green Sulfur Bacteria

    DEFF Research Database (Denmark)

    Ussery, David; Davenport, C; Tümmler, B

    2010-01-01

    Eleven completely sequenced Chlorobi genomes were compared in oligonucleotide usage, gene contents, and synteny. The green sulfur bacteria (GSB) are equipped with a core genome that sustains their anoxygenic phototrophic lifestyle by photosynthesis, sulfur oxidation, and CO(2) fixation. Whole...... weight of 10(6), and are probably instrumental for the bacteria to generate their own intimate (micro)environment....

  11. Aerobic N2O emission for activated sludge acclimated under different aeration rates in the multiple anoxic and aerobic process.

    Science.gov (United States)

    Wang, Huoqing; Guan, Yuntao; Pan, Min; Wu, Guangxue

    2016-05-01

    Nitrous oxide (N2O) is a potent greenhouse gas that can be emitted during biological nitrogen removal. N2O emission was examined in a multiple anoxic and aerobic process at the aeration rates of 600mL/min sequencing batch reactor (SBRL) and 1200mL/min (SBRH). The nitrogen removal percentage was 89% in SBRL and 71% in SBRH, respectively. N2O emission mainly occurred during the aerobic phase, and the N2O emission factor was 10.1% in SBRL and 2.3% in SBRH, respectively. In all batch experiments, the N2O emission potential was high in SBRL compared with SBRH. In SBRL, with increasing aeration rates, the N2O emission factor decreased during nitrification, while it increased during denitrification and simultaneous nitrification and denitrification (SND). By contrast, in SBRH the N2O emission factor during nitrification, denitrification and SND was relatively low and changed little with increasing aeration rates. The microbial competition affected the N2O emission during biological nitrogen removal.

  12. Co(salophen)-Catalyzed Aerobic Oxidation of p-Hydroquinone: Mechanism and Implications for Aerobic Oxidation Catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Anson, Colin W.; Ghosh, Soumya; Hammes-Schiffer, Sharon; Stahl, Shannon S.

    2016-03-30

    Macrocyclic metal complexes and p-benzoquinones are commonly used as co-catalytic redox mediators in aerobic oxidation reactions. In an effort to gain insight into the mechanism and energetic efficiency of these reactions, we investigated Co(salophen)-catalyzed aerobic oxidation of p-hydroquinone. Kinetic and spectroscopic data suggest that the catalyst resting-state consists of an equilibrium between a CoII(salophen) complex, a CoIII-superoxide adduct, and a hydrogen-bonded adduct between the hydroquinone and the CoIII–O2 species. The kinetic data, together with density functional theory data, suggest that the turnover-limiting step features proton-coupled electron transfer from a semi-hydroquinone species and a CoIII-hydroperoxide intermediate. Additional experimental and computational data suggest that a coordinated H2O2 intermediate oxidizes a second equivalent of hydroquinone. This research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center, funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. The NSF provided partial support for the EPR instrumentation (NSF CHE-0741901).

  13. Effects of strengthening and aerobic exercises on pain severity and function in patients with knee rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Nader Rahnama

    2012-01-01

    Conclusions: It can be concluded that an aerobic exercise program improves functional and walking ability in patients with knee RA, and strengthening exercise has more efficient effect on knee ROM, both aerobic and strengthening exercises can equally relieve pain.

  14. Aerobic and anaerobic organism productivity as factors that determine the level of physical health

    Directory of Open Access Journals (Sweden)

    Serorez T.B.

    2014-04-01

    Full Text Available Purpose : to identify and assess the level of physical health of men of the first coming of age 21-23 years. Material : the study involved 413 students and 17 teachers and sports doctors. Results : the influence of cross-country training aerobic and anaerobic focus on physical performance, aerobic and anaerobic performance of the student body. The efficiency impact exercises using running loads of aerobic and anaerobic focus on the physical health of students. It is proved that the level of aerobic performance drops to safe limits and requires correction. To correct the body's aerobic performance is recommended to use for running load. Conclusions: found that the correction would be the most efficient and effective through the development and implementation of health technologies based on the use of extracurricular classes jogging exercises. It should take into account the frequency and methods of learning, physical work mode power supply and energy value of each class.

  15. Biodegradation of Acid Anthraquinone Dye in a Facultative-aerobic Process: Kinetics and Products

    Institute of Scientific and Technical Information of China (English)

    LI Yin; LI Zai-lei

    2009-01-01

    The transformation of an anthraquinone dye blue 324 in a facultative-aerobic (F-A) system was investigated. Kinetic parameter study showed that higher Vmax coupled with more recalcitrant chemical oxygen demand (COD) were found in the facuitative biofilm reactor (FBR) than in the aerobic reactor (AR). Results of the product analyses indicated that most of dye molecular could be facultatively broken down into simple intermediates, which would be further degraded under subsequent aerobic condition. The main metabolites in each reactor were detected by infrared (FT-IR) and high performance liquid chromatography and mass spectrometry (HPLC-MS). Comparison of the toxicities among the dye and its metabolites was conducted, surprisingly, the colorless intermediates from FBR possessed less inhibitory than original dye and the median effective luminescence concentration (EC50) in 15 min for aerobic effluent could not be detected, showing that hardly toxic products existed in the aerobic process effluent.

  16. Coupled anaerobic/aerobic biodegradation of 2,4,6 trichlorophenol

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Degradation of 2, 4, 6-trichlorophenol(TCP) with co-immobilizing anaerobic granular sludge and isolated aerobic bacterial specieswas studied in coupled anaerobic/aerobic integrated reactors. The synergism of aerobes and anaerobes within co-immobilized granule mightfacilitate degrading the TCP and exchange of anaerobic metabolites 4-CP, which promoted system organic removal efficiency and recovered fromorganic shock-loads more quickly. The biomass specific activities experiment further confirmed that strict anaerobes be not affected over thecourse of this experiment by the presence of an oxic environment, aerobic activity predominated in the outer co-immobilized granule layers,while the interior was characterized by anaerobic activity. The co-immobilized granule could thus enable both aerobic and anaerobic microbesfunction in the same reactor and thereby integrate the oxidative and reductive catabolism.

  17. Aerobic fitness is associated with greater white matter integrity in children

    Directory of Open Access Journals (Sweden)

    Laura eChaddock-Heyman

    2014-08-01

    Full Text Available Aerobic fitness has been found to play a positive role in brain and cognitive health of children. Yet, many of the neural biomarkers related to aerobic fitness remain unknown. Here, using diffusion tensor imaging (DTI, we demonstrated that higher aerobic fitness was related to greater estimates of white matter microstructure in children. Higher fit 9- and 10-year-old children showed greater fractional anisotropy (FA in sections of the corpus callosum, corona radiata, and superior longitudinal fasciculus, compared to lower fit children. The FA effects were primarily characterized by aerobic fitness differences in radial diffusivity (RD, thereby raising the possibility that estimates of myelination may vary as a function of individual differences in fitness during childhood. White matter structure may be another potential neural mechanism of aerobic fitness that assists in efficient communication between gray matter regions as well as the integration of regions into networks.

  18. Complete remediation of PCE contaminated unsaturated soils by sequential anaerobic-aerobic bioventing.

    Science.gov (United States)

    Mihopoulos, P G; Suidan, M T; Sayles, G D

    2001-01-01

    Bioventing principles have been applied to completely dechlorinate tetrachloroethylene vapors in the unsaturated zone in a sequential anaerobic-aerobic pattern. The aerobic step yields trans-DCE and VC as PCE reductive dechlorination byproducts, while TCE and cis-DCE are observed as intermediates. The aerobic step results in rapid oxidation of the VC and trans-DCE to carbon dioxide. Hydrogen was delivered in the gas phase as a reducing agent for the anaerobic step at levels of 1%, and oxygen at 4.2% was used as an electron acceptor in the aerobic step. PCE and VC half lives in the anaerobic and aerobic steps respectively, where less than 10 min.

  19. Development of a specific anaerobic field test for aerobic gymnastics.

    Science.gov (United States)

    Alves, Christiano Robles Rodrigues; Borelli, Marcello Tadeu Caetano; Paineli, Vitor de Salles; Azevedo, Rafael de Almeida; Borelli, Claudia Cristine Gomes; Lancha Junior, Antônio Herbert; Gualano, Bruno; Artioli, Guilherme Giannini

    2015-01-01

    The current investigation aimed to develop a valid specific field test to evaluate anaerobic physical performance in Aerobic Gymnastics athletes. We first designed the Specific Aerobic Gymnast Anaerobic Test (SAGAT), which included gymnastics-specific elements performed in maximal repeated sprint fashion, with a total duration of 80-90 s. In order to validate the SAGAT, three independent sub-studies were performed to evaluate the concurrent validity (Study I, n=8), the reliability (Study II, n=10) and the sensitivity (Study III, n=30) of the test in elite female athletes. In Study I, a positive correlation was shown between lower-body Wingate test and SAGAT performance (Mean power: p = 0.03, r = -0.69, CI: -0.94 to 0.03 and Peak power: p = 0.02, r = -0.72, CI: -0.95 to -0.04) and between upper-body Wingate test and SAGAT performance (Mean power: p = 0.03, r = -0.67, CI: -0.94 to 0.02 and Peak power: p = 0.03, r = -0.69, CI: -0.94 to 0.03). Additionally, plasma lactate was similarly increased in response to SAGAT (p = 0.002), lower-body Wingate Test (p = 0.021) and a simulated competition (p = 0.007). In Study II, no differences were found between the time to complete the SAGAT in repeated trials (p = 0.84; Cohen's d effect size = 0.09; ICC = 0.97, CI: 0.89 to 0.99; MDC95 = 0.12 s). Finally, in Study III the time to complete the SAGAT was significantly lower during the competition cycle when compared to the period before the preparatory cycle (p Gymnastics training period. Taken together, these data have demonstrated that SAGAT is a specific, reliable and sensitive measurement of specific anaerobic performance in elite female Aerobic Gymnastics, presenting great potential to be largely applied in training settings.

  20. 210Pb and 210Po, manganese and iron cycling across the O2/H2S interface of a permanently anoxic fjord: Framvaren, Norway

    Science.gov (United States)

    Swarzenski, Peter W.; McKee, Brent A.; Sorensen, Kai; Todd, James F.

    1999-01-01

    Vertical profiles of dissolved and particulate 210Po and 210b were measured across the redox transition zone at Station F1 in Framvaren Fjord, Norway. In this fjord, a sharp decrease in pH above the O2/H2S interface facilitates the aerobic dissolution of MnO2. In contrast, Fe(II) concentrations begin to increase only at the O2/H2S interface depth. Activity profiles reveal that dissolved 210Po and 210Pb are sequestered efficiently by particulates in surface waters. As polonium-210 and lead-210 activities descend down into the aerobic manganese reduction (AMR) zone, they are remobilized during the reductive dissolution of the carrier phase oxyhydroxides. Both 210Po and 210Pb are highly enriched at the O2/H2S interface where an active community of microbes, such as anoxygenic phototrophs (e.g., Chromatium, Chlorobium sp.), thrives. The coincident peaks in 210Po, 210Pb and microbial biomass suggest a strong biological influence on the behavior of these radionuclides. There is a strong covariance between the vertical distribution of Mn and Pb, indicating that their redox cycling is closely coupled and is likely microbially mediated.

  1. Surface EMG based muscle activity analysis for aerobic cyclist.

    Science.gov (United States)

    Balasubramanian, Venkatesh; Jayaraman, Srinivasan

    2009-01-01

    In this study, we determined the muscle activity of aerobic cyclist on biceps brachii medial, trapezius medial, latissimus dorsi medial, and erector spinae muscles bilaterally during 30 min of cycling. Thirteen male volunteers were chosen and placed in two groups (with and without low back pain (LBP)). Surface electromyography (sEMG) was recorded bilaterally from selected muscle groups for 30 min of cycling for each subject. Statistical tests were performed to determine the difference in fatigue, using mean power frequency difference. LBP group showed a significantly higher fatigue (p<0.05) in left biceps brachii medial when compared to the control group. High fatigue in the back muscles in the LBP group was not found; however, when linear regression was performed for these individuals, the data showed a possibility of worsening in their condition due to 30 min of cycling.

  2. EFFECTS OF THREE FEEDBACK CONDITIONS ON AEROBIC SWIM SPEEDS

    Directory of Open Access Journals (Sweden)

    Pedro Pérez Soriano

    2009-03-01

    Full Text Available The purpose of this study was twofold: (a to develop an underwater chronometer capable to provide feedback while the athlete is swimming, as well as being a control tool for the coach, and (b to analyse its feedback effect on swim pace control compared with feedback provided by the coach and with no feedback, in 25 m and 50 m swimming pools. 30 male swimmers of national level volunteer to participate. Each swimmer swam 3 x 200 m at aerobic speed (AS and 3 x 200 m just under the anaerobic threshold speed (AnS, each swam repetition with a different feedback condition: chronometer, coach and without feedback. Results (a validate the chronometer system developed and (b show that swimmers pace control is affected by the type of feedback provided, the swim speed elected and the size of the swimming pool

  3. Characteristics of Pb2+ biosorption with aerobic granular biomass

    Institute of Scientific and Technical Information of China (English)

    YAO Lei; YE ZhengFang; WANG ZhongYou; NI JinRen

    2008-01-01

    Experimental studies were conducted on the feasibility of aerobic granular biomass as a novel type of biosorbent for Pb2+ removal. The results show that the initial pH, Pb2+ concentration (C0) and biomass concentration (X0) affected the biosorption process significantly. Both the Freundlich and Langmuir isotherm models describe the biosorption process accurately, with correlation coefficients of 0.932 and 0.959 respectively. The Pb2+ biosorption kinetics is interpreted as having two stages, with the second stage described reasonably well by a Lagergren pseudo-second order model. Moreover, the surface change of granular biomass after the Pb2+ biosorption process appears to be caused by ion exchange and metal chelation according to the analysis results of Environmental Scanning Electron Microscopy (ESEM) and Energy Dispersive X-ray Spectroscopy (EDX).

  4. Marine oscillatoria (Trichodesmium): explanation for aerobic nitrogen fixation without heterocysts.

    Science.gov (United States)

    Carpenter, E J; Price, C C

    1976-03-26

    Nitrogen fixation in marine Oscillatoria appears to be associated with differentiated cells located in the center of the colony. These central cells exhibit reduced pigmentation relative to peripherally located cells and do not incorporate 14CO2 in photosynthesis. Central cells apparently do not produce O2 which would deactivate nitrogenase. When central cells are exposed to O2 via disruption of the colonies, N2 fixation (acetylene reduction) decreases sharply even though individual trichomes remain intact. Disruption of colonies in the absence of O2 does not cause reduced nitrogenase activity. In the sea, turbulence from wave action apparently separates trichomes allowing O2 to enter thus decreasing nitrogenase activity. These observations explain how Oscillatoria is able to fix N2 without heterocysts in an aerobic environment and why it blooms virtually always occur in calm seas.

  5. Biological phosphorus uptake under anoxic and aerobic conditions

    DEFF Research Database (Denmark)

    Kerrn-Jespersen, Jens Peter; Henze, Mogens

    1993-01-01

    Biological phosphorus removal was investigated under anoxic and aerobic conditions. Tests were made to establish whether phosphorus accumulating bacteria can take up phosphate under anoxic conditions and thus utilise nitrate as oxidant. Furthermore, it was tested how the amount of organic matter...... sludge from two different pilot plants incorporating phosphorus removal. The results showed that the phosphorus accumulating bacteria can be divided into two groups in respect of process; one group capable of utilising only oxygen as oxidant and another group capable of utilising both oxygen and nitrate...... taken up by the phosphorus accumulating bacteria during the anaerobic phase affects the total denitrification rate, as well as the rate at which the phosphorus accumulating bacteria take up phosphate under anoxic conditions. The tests were conducted as batch experiments in 21. reactors with activated...

  6. Enzymes and Genes Involved in Aerobic Alkane Degradation

    Directory of Open Access Journals (Sweden)

    Zongze eShao

    2013-05-01

    Full Text Available Alkanes are major constituents of crude oil. They are also present at low concentrations in diverse non-contaminated because many living organisms produce them as chemo-attractants or as protecting agents against water loss. Alkane degradation is a widespread phenomenon in nature. The numerous microorganisms, both prokaryotic and eukaryotic, capable of utilizing alkanes as a carbon and energy source, have been isolated and characterized. This review summarizes the current knowledge of how bacteria metabolize alkanes aerobically, with a particular emphasis on the oxidation of long-chain alkanes, including factors that are responsible for chemotaxis to alkanes , transport across cell membrane of alkanes , the regulation of alkane degradation gene and initial oxidation.

  7. The relationship between aerobic exercise and cognition: is movement medicinal?

    Science.gov (United States)

    Lojovich, Jeanne M

    2010-01-01

    Each year approximately 1.5 million individuals sustain traumatic brain injuries often resulting in difficulties in memory and executive function that limit independence. Aerobic exercise not only has been found to impact cardiovascular systems but has also shown benefits to brain function itself and specifically in the domain of memory and learning. Recent evidence is shedding light on the mechanisms possibly impacting cognitive performance following the participation in exercise. Literature has demonstrated increased hemodynamics within the brain, changes in neurotransmitters, and increasing levels of brain-derived neurotrophic factor that stimulates neurogenesis, and resistance to further injury. This review article explores the current literature and the possibility of exercise acting as an adjunct treatment to enhance the effectiveness of cognitive rehabilitation.

  8. Aerobic Exercise in People with Schizophrenia: Neural and Neurocognitive Benefits.

    Science.gov (United States)

    Vakhrusheva, Julia; Marino, Brielle; Stroup, T Scott; Kimhy, David

    2016-06-01

    Schizophrenia is characterized by extensive neurocognitive deficits, which are linked to greater disability, poorer functional outcome, and have been suggested to impact daily functioning more than clinical symptoms. Aerobic exercise (AE) has emerged as a potential intervention. This review examines the impact of AE on brain structure and function along with neurocognitive performance in individuals with schizophrenia. Preliminary evidence indicates that AE can increase hippocampal volume and cortical thickness, in addition to exerting a neuroprotective effect against hippocampal volume decrease and cortical thinning. There is also evidence that AE is able to significantly increase serum brain-derived neurotrophic factor (BDNF) levels, which are implicated in neurogenesis, neuroplasticity, and cognitive improvement. Finally, evidence suggests that AE plays a significant role in improving overall cognition, including improvements in processing speed, working memory, and visual learning. The authors discuss the implications of the findings and provide recommendations for future research and areas of inquiry.

  9. Targeting aerobic glycolysis: 3-bromopyruvate as a promising anticancer drug.

    Science.gov (United States)

    Cardaci, Simone; Desideri, Enrico; Ciriolo, Maria Rosa

    2012-02-01

    The Warburg effect refers to the phenomenon whereby cancer cells avidly take up glucose and produce lactic acid under aerobic conditions. Although the molecular mechanisms underlying tumor reliance on glycolysis remains not completely clear, its inhibition opens feasible therapeutic windows for cancer treatment. Indeed, several small molecules have emerged by combinatorial studies exhibiting promising anticancer activity both in vitro and in vivo, as a single agent or in combination with other therapeutic modalities. Therefore, besides reviewing the alterations of glycolysis that occur with malignant transformation, this manuscript aims at recapitulating the most effective pharmacological therapeutics of its targeting. In particular, we describe the principal mechanisms of action and the main targets of 3-bromopyruvate, an alkylating agent with impressive antitumor effects in several models of animal tumors. Moreover, we discuss the chemo-potentiating strategies that would make unparalleled the putative therapeutic efficacy of its use in clinical settings.

  10. Aerobic Linear Allylic C-H Amination: Overcoming Benzoquinone Inhibition.

    Science.gov (United States)

    Pattillo, Christopher C; Strambeanu, Iulia I; Calleja, Pilar; Vermeulen, Nicolaas A; Mizuno, Tomokazu; White, M Christina

    2016-02-03

    An efficient aerobic linear allylic C-H amination reaction is reported under palladium(II)/bis-sulfoxide/Brønsted base catalysis. The reaction operates under preparative, operationally simple conditions (1 equiv of olefin, 1 atm O2 or air) with reduced Pd(II)/bis-sulfoxide catalyst loadings while providing higher turnovers and product yields than systems employing stoichiometric benzoquinone (BQ) as the terminal oxidant. Pd(II)/BQ π-acidic interactions have been invoked in various catalytic processes and are often considered beneficial in promoting reductive functionalizations. When such electrophilic activation for functionalization is not needed, however, BQ at high concentrations may compete with crucial ligand (bis-sulfoxide) binding and inhibit catalysis. Kinetic studies reveal an inverse relationship between the reaction rate and the concentration of BQ, suggesting that BQ is acting as a ligand for Pd(II) which results in an inhibitory effect on catalysis.

  11. Corrosion inhibition of mild steel by aerobic biofilm

    Energy Technology Data Exchange (ETDEWEB)

    Chongdar, Shobhana [Naval Materials Research Laboratory, Addl. Ambarnath 421506 (India); Gunasekaran, G. [Naval Materials Research Laboratory, Addl. Ambarnath 421506 (India)]. E-mail: gunanmrl@rediffmail.com; Kumar, Pradeep [Naval Materials Research Laboratory, Addl. Ambarnath 421506 (India)

    2005-08-30

    Mild steel electrodes were incubated in phosphate-buffered basal salt solution (BSS) having two different aerobic bacteria, viz. Pseudomonas alcaligenes and Pseudomonas cichorii. In the medium containing P. cichorii, significant reduction in the corrosion rate was observed due to the surface reaction leading to the formation of corrosion inhibiting bacterial biofilm. With a view to understand the mechanism of microbially influenced corrosion/corrosion inhibition, electrochemical and biological experiments such as electrochemical impedance spectroscopy (EIS) measurements and biochemical analysis were made. The exposed surfaces were examined using scanning electron micrographs (SEM), energy dispersive spectroscopy (EDS) and electron spectroscopy for chemical analysis (ESCA). The scraped surface film was also examined using FT-IR spectroscopy. The results suggested that mild steel surface contained iron oxide-phosphate layer covered with bacteria and exo polymeric substance (EPS)/iron-EPS complex for P. cichorii and iron oxides and iron phosphate for P. alcaligenes.

  12. Anaerobic/aerobic treatment of selected azo dyes in wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Seshadri, S.; Bishop, P.L. (Univ. of Cincinnati, OH (United States). Dept. of Civil and Environmental Engineering); Agha, A.M. (Univ. of Aleppo (Syrian Arab Republic). Faculty of Civil Engineering)

    1994-01-01

    Azo dyes represent the largest class of dyes in use today. Current environmental concern with these dyes revolves around the potential carcinogenic health risk presented by these dyes or their intermediate biodegradation products when exposed to microflora in the human digestive tract. These dyes may build up in the environment, since many wastewater treatment plants allow these dyes to pass through the system virtually untreated. The initial step in the degradation of these dyes is the cleavage of the Azo bond. This cleavage is often impossible under aerobic conditions, but has been readily demonstrated under anaerobic conditions. The focus of the study was to determine the feasibility of using an anaerobic fluidized-bed reactor to accomplish this cleavage. The effects of typical process variables such as hydraulic retention time (HRT), influent dye concentration levels, and degree of bed fluidization on removal efficiencies were also studied. The four dyes selected for this study were Acid-Orange 7, Acid-Orange 8, Acid-Orange 10, and Acid-Red 14. The effectiveness of using a bench-scale-activated sludge reactor as a sequenced second stage was also examined. Results indicate that nearly complete cleavage of the Azo bond is easily accomplished for each of the four dyes under hydraulic retention times of either 12 or 24 h. Initial results indicate, though, that aromatic amine by-products remain. The sequenced second stage was able to remove the remaining Chemical Oxygen Demand (COD) load to acceptable levels. Work is presently underway to determine the face of the anaerobic by-products in the aerobic second stage.

  13. Aerobic degradation of sulfanilic acid using activated sludge.

    Science.gov (United States)

    Chen, Gang; Cheng, Ka Yu; Ginige, Maneesha P; Kaksonen, Anna H

    2012-01-01

    This paper evaluates the aerobic degradation of sulfanilic acid (SA) by an acclimatized activated sludge. The sludge was enriched for over three months with SA (>500 mg/L) as the sole carbon and energy source and dissolved oxygen (DO, >5mg/L) as the primary electron acceptor. Effects of aeration rate (0-1.74 L/min), DO concentration (0-7 mg/L) and initial SA concentration (104-1085 mg/L) on SA biodegradation were quantified. A modified Haldane substrate inhibition model was used to obtain kinetic parameters of SA biodegradation and oxygen uptake rate (OUR). Positive linear correlations were obtained between OUR and SA degradation rate (R(2)≥ 0.91). Over time, the culture consumed more oxygen per SA degraded, signifying a gradual improvement in SA mineralization (mass ratio of O(2): SA at day 30, 60 and 120 were 0.44, 0.51 and 0.78, respectively). The concomitant release of near stoichiometric quantity of sulphate (3.2 mmol SO(4)(2-) released from 3.3 mmol SA) and the high chemical oxygen demand (COD) removal efficacy (97.1%) indicated that the enriched microbial consortia could drive the overall SA oxidation close to a complete mineralization. In contrast to other pure-culture systems, the ammonium released from the SA oxidation was predominately converted into nitrate, revealing the presence of ammonium-oxidizing bacteria (AOB) in the mixed culture. No apparent inhibitory effect of SA on the nitrification was noted. This work also indicates that aerobic SA biodegradation could be monitored by real-time DO measurement.

  14. Physical injury stimulates aerobic methane emissions from terrestrial plants

    Directory of Open Access Journals (Sweden)

    Z.-P. Wang

    2009-04-01

    Full Text Available Physical injury is common in terrestrial plants as a result of grazing, harvesting, trampling, and extreme weather events. Previous studies demonstrated enhanced emission of non-microbial CH4 under aerobic conditions from plant tissues when they were exposed to increasing UV radiation and temperature. Since physical injury is also a form of environmental stress, we sought to determine whether it would also affect CH4 emissions from plants. Physical injury (cutting stimulated CH4 emission from fresh twigs of Artemisia species under aerobic conditions. More cutting resulted in more CH4 emissions. Hypoxia also enhanced CH4 emission from both uncut and cut Artemisia frigida twigs. Physical injury typically results in cell wall degradation, which may either stimulate formation of reactive oxygen species (ROS or decrease scavenging of them. Increased ROS activity might explain increased CH4 emission in response to physical injury and other forms of stress. There were significant differences in CH4 emissions among 10 species of Artemisia, with some species emitting no detectable CH4 under any circumstances. Consequently, CH4 emissions may be species-dependent and therefore difficult to estimate in nature based on total plant biomass. Our results and those of previous studies suggest that a variety of environmental stresses stimulate CH4 emission from a wide variety of plant species. Global change processes, including climate change, depletion of stratospheric ozone, increasing ground-level ozone, spread of plant pests, and land-use changes, could cause more stress in plants on a global scale, potentially stimulating more CH4 emission globally.

  15. Assessment of bacterial and structural dynamics in aerobic granular biofilms

    Directory of Open Access Journals (Sweden)

    David G. Weissbrodt

    2013-07-01

    Full Text Available Aerobic granular sludge is based on self-granulated flocs forming mobile biofilms with a gel-like consistence. Bacterial and structural dynamics from flocs to granules were followed in anaerobic-aerobic sequencing batch reactors fed with synthetic wastewater, namely a bubble column (BC-SBR operated under wash-out conditions for fast granulation, and two stirred-tank enrichments of Accumulibacter (PAO-SBR and Competibacter (GAO-SBR operated at steady-state. In the BC-SBR, granules formed within two weeks by swelling of Zoogloea colonies around flocs, developing subsequently smooth zoogloeal biofilms. However, Zoogloea predominance (37-79% led to deteriorated nutrient removal during the first months of reactor operation. Upon maturation, improved nitrification (80-100%, nitrogen removal (43-83%, and high but unstable dephosphatation (75-100% were obtained. Proliferation of dense clusters of nitrifiers, Accumulibacter, and Competibacter from granule cores outwards resulted in heterogeneous bioaggregates, inside which only low abundance Zoogloea (<5% were detected in biofilm interstices. The presence of different extracellular glycoconjugates detected by fluorescence lectin-binding analysis showed the complex nature of the intracellular matrix of these granules. In the PAO-SBR, granulation occurred within two months with abundant and active Accumulibacter populations (56±10% that were selected under full anaerobic uptake of volatile fatty acids and that aggregated as dense clusters within heterogeneous granules. Flocs self-granulated in the GAO-SBR after 480 days during a period of over-aeration caused by biofilm growth on the oxygen sensor. Granules were dominated by heterogeneous clusters of Competibacter (37±11%. Zoogloea were never abundant in biomass of both PAO- and GAO-SBRs. This study showed that Zoogloea, Accumulibacter, and Competibacter affiliates can form granules, and that the granulation mechanisms rely on the dominant population

  16. Aerobic power and peak power of elite America's Cup sailors.

    Science.gov (United States)

    Neville, Vernon; Pain, Matthew T G; Folland, Jonathan P

    2009-05-01

    Big-boat yacht racing is one of the only able bodied sporting activities where standing arm-cranking ('grinding') is the primary physical activity. However, the physiological capabilities of elite sailors for standing arm-cranking have been largely unreported. The purpose of the study was to assess aerobic parameters, VO(2peak) and onset of blood lactate (OBLA), and anaerobic performance, torque-crank velocity and power-crank velocity relationships and therefore peak power (P (max)) and optimum crank-velocity (omega(opt)), of America's Cup sailors during standing arm-cranking. Thirty-three elite professional sailors performed a step test to exhaustion, and a subset of ten grinders performed maximal 7 s isokinetic sprints at different crank velocities, using a standing arm-crank ergometer. VO(2peak) was 4.7 +/- 0.5 L/min (range 3.6-5.5 L/min) at a power output of 332 +/- 44 W (range 235-425 W). OBLA occurred at a power output of 202 +/- 31 W (61% of W(max)) and VO(2) of 3.3 +/- 0.4 L/min (71% of VO(2peak)). The torque-crank velocity relationship was linear for all participants (r = 0.9 +/- 0.1). P (max) was 1,420 +/- 37 W (range 1,192-1,617 W), and omega(opt) was 125 +/- 6 rpm. These data are among the highest upper-body anaerobic and aerobic power values reported. The unique nature of these athletes, with their high fat-free mass and specific selection and training for standing arm cranking, likely accounts for the high values. The influence of crank velocity on peak power implies that power production during on-board 'grinding' may be optimised through the use of appropriate gear-ratios and the development of efficient gear change mechanisms.

  17. Isolation of aerobic bacteria from ticks infested sheep in Iraq

    Institute of Scientific and Technical Information of China (English)

    Waleed Ibrahem Jalil; Mohammad Mushgil Zenad

    2016-01-01

    Objective:To highlight the presence of aerobic bacteria in live ticks infested sheep,in Diyala Governorate,Iraq.Methods:One hundred and thirty adult alive ticks were picked up from sheep which were reared in different farms in Diyala Governorate,Iraq,during the period from November 2012 to May 2013.Ticks were classified in the Natural History Museum in Baghdad.They were dissected aseptically for extraction of the salivary gland and midgut.The removed tissue from each organ was inoculated in buffer peptone water(1%)and incubated for 2 h at 37 °C,to maintain weak and/or injured bacterial cells,then transmitted to nutrient broth incubated at 37 °C for 18 h.Culturing was done on three solid bacteriological media(nutrient,blood and McConkey agars),and then incubated at37 ℃ for 24 h.Bacterial identification was performed by using multiple biochemical tests and API-20 strips.Data were analyzed by using Statistical Analysis System version 9.1,2010.Chi-square test was used for comparison at significant level of P ≤ 0.05.Results:Two species of ticks were identified[Rhipicephalus(Boophilus) annulatus and Hyalomma turanicum].High bacterial isolation rate was observed(483 isolates).A significant high isolation rate was recorded from Rhipicephalus annulatus(63.14%).Six bacterial species were identified[Escherichia coli(28.36%),Pseudomonas aeruginosa(18.01%),Bacillus cereus(14.69%),Staphylococcus aureus(13.66%),Citrobacter freundii(13.04%),and Enterobacter species(12.21%)].Also the high bacterial isolation rates were recorded in the temperate months(November,March and April);these coincided with high reproductive performance of ticks.Conclusions:The high isolation rate of aerobic pathogens from ticks might reflect the active contribution of this arthropod in environmental contamination and increase the probability of transmitting bacterial pathogens to their hosts.

  18. Isolation of aerobic bacteria from ticks infested sheep in Iraq

    Institute of Scientific and Technical Information of China (English)

    Waleed Ibrahem Jalil; Mohammad Mushgil Zenad

    2016-01-01

    Objective: To highlight the presence of aerobic bacteria in live ticks infested sheep, in Diyala Governorate, Iraq. Methods: One hundred and thirty adult alive ticks were picked up from sheep which were reared in different farms in Diyala Governorate, Iraq, during the period from November 2012 to May 2013. Ticks were classified in the Natural History Museum in Baghdad. They were dissected aseptically for extraction of the salivary gland and mid-gut. The removed tissue from each organ was inoculated in buffer peptone water (1%) and incubated for 2 h at 37℃, to maintain weak and/or injured bacterial cells, then transmitted to nutrient broth incubated at 37℃ for 18 h. Culturing was done on three solid bacteriological media (nutrient, blood and McConkey agars), and then incubated at 37℃ for 24 h. Bacterial identification was performed by using multiple biochemical tests and API-20 strips. Data were analyzed by using Statistical Analysis System version 9.1, 2010. Chi-square test was used for comparison at significant level of P ≤0.05. Results: Two species of ticks were identified [Rhipicephalus (Boophilus) annulatus and Hyalomma turanicum]. High bacterial isolation rate was observed (483 isolates). A significant high isolation rate was recorded from Rhipicephalus annulatus (63.14%). Six bacterial species were identified [Escherichia coli (28.36%), Pseudomonas aeruginosa (18.01%), Bacillus cereus (14.69%), Staphylococcus aureus (13.66%), Citrobacter freundii (13.04%), and Enterobacter species (12.21%)]. Also the high bacterial isolation rates were recorded in the temperate months (November, March and April); these coin-cided with high reproductive performance of ticks. Conclusions: The high isolation rate of aerobic pathogens from ticks might reflect the active contribution of this arthropod in environmental contamination and increase the probability of transmitting bacterial pathogens to their hosts.

  19. Aerobic biodegradation of organic compounds in hydraulic fracturing fluids.

    Science.gov (United States)

    Kekacs, Daniel; Drollette, Brian D; Brooker, Michael; Plata, Desiree L; Mouser, Paula J

    2015-07-01

    Little is known of the attenuation of chemical mixtures created for hydraulic fracturing within the natural environment. A synthetic hydraulic fracturing fluid was developed from disclosed industry formulas and produced for laboratory experiments using commercial additives in use by Marcellus shale field crews. The experiments employed an internationally accepted standard method (OECD 301A) to evaluate aerobic biodegradation potential of the fluid mixture by monitoring the removal of dissolved organic carbon (DOC) from an aqueous solution by activated sludge and lake water microbial consortia for two substrate concentrations and four salinities. Microbial degradation removed from 57 % to more than 90 % of added DOC within 6.5 days, with higher removal efficiency at more dilute concentrations and little difference in overall removal extent between sludge and lake microbe treatments. The alcohols isopropanol and octanol were degraded to levels below detection limits while the solvent acetone accumulated in biological treatments through time. Salinity concentrations of 40 g/L or more completely inhibited degradation during the first 6.5 days of incubation with the synthetic hydraulic fracturing fluid even though communities were pre-acclimated to salt. Initially diverse microbial communities became dominated by 16S rRNA sequences affiliated with Pseudomonas and other Pseudomonadaceae after incubation with the synthetic fracturing fluid, taxa which may be involved in acetone production. These data expand our understanding of constraints on the biodegradation potential of organic compounds in hydraulic fracturing fluids under aerobic conditions in the event that they are accidentally released to surface waters and shallow soils.

  20. Assessment of bacterial and structural dynamics in aerobic granular biofilms

    Science.gov (United States)

    Weissbrodt, David G.; Neu, Thomas R.; Kuhlicke, Ute; Rappaz, Yoan; Holliger, Christof

    2013-01-01

    Aerobic granular sludge (AGS) is based on self-granulated flocs forming mobile biofilms with a gel-like consistence. Bacterial and structural dynamics from flocs to granules were followed in anaerobic-aerobic sequencing batch reactors (SBR) fed with synthetic wastewater, namely a bubble column (BC-SBR) operated under wash-out conditions for fast granulation, and two stirred-tank enrichments of Accumulibacter (PAO-SBR) and Competibacter (GAO-SBR) operated at steady-state. In the BC-SBR, granules formed within 2 weeks by swelling of Zoogloea colonies around flocs, developing subsequently smooth zoogloeal biofilms. However, Zoogloea predominance (37–79%) led to deteriorated nutrient removal during the first months of reactor operation. Upon maturation, improved nitrification (80–100%), nitrogen removal (43–83%), and high but unstable dephosphatation (75–100%) were obtained. Proliferation of dense clusters of nitrifiers, Accumulibacter, and Competibacter from granule cores outwards resulted in heterogeneous bioaggregates, inside which only low abundance Zoogloea (<5%) were detected in biofilm interstices. The presence of different extracellular glycoconjugates detected by fluorescence lectin-binding analysis showed the complex nature of the intracellular matrix of these granules. In the PAO-SBR, granulation occurred within two months with abundant and active Accumulibacter populations (56 ± 10%) that were selected under full anaerobic uptake of volatile fatty acids and that aggregated as dense clusters within heterogeneous granules. Flocs self-granulated in the GAO-SBR after 480 days during a period of over-aeration caused by biofilm growth on the oxygen sensor. Granules were dominated by heterogeneous clusters of Competibacter (37 ± 11%). Zoogloea were never abundant in biomass of both PAO- and GAO-SBRs. This study showed that Zoogloea, Accumulibacter, and Competibacter affiliates can form granules, and that the granulation mechanisms rely on the dominant

  1. Development of the aerobic spoilage flora of chilled rabbit meat.

    Science.gov (United States)

    Rodríguez-Calleja, José M; García-López, María-Luisa; Santos, Jesús A; Otero, Andrés

    2005-06-01

    Even though worldwide production of rabbit meat is over 1,000,000ton, little information is available on rabbit meat microbiology. This paper reports on the microflora developing on chill-stored rabbit carcasses. Four different lots of 24h post-mortem rabbit carcasses dressed and kept at 0°C in a medium-size abattoir were collected and evaluated for sensory, physicochemical and microbiological changes during aerobic storage at 3±1°C. Mean initial pH value (pH(24)), extract-release volume (ERV) and lactate content of Biceps femoris muscle, were 6.26±0.20, 13.50±3.50ml and 0.70±0.07%, respectively. As with other muscle foods kept chilled in air, pH increased and ERV and lactate decreased as storage progressed. Initial levels (logcfu/g) of aerobes (APC), psychrotrophic flora, Pseudomonas spp., Brochothrix thermosphacta, lactic acid bacteria, Enterobacteriaceae and yeasts were 4.76±0.31, 4.81±0.81, 3.39±1.12, 2.01±0.92, 2.76±0.51, 0.49±0.45 and 3.46±0.32, respectively. Pseudomonads, most of them fluorescent, and to a lesser extent B. thermosphacta and yeasts grew faster than the remaining microorganisms and became predominant at the end of the shelf life. Carcasses spoiled when mean APC, psychrotrophic and pseudomonads numbers were ca. 8logcfu/g, their mean shelf life being estimated at 6.8 days. A lot of DFD-like rabbit carcasses, with higher pH and lower ERV values but similar microbial loads to normal meat, developed a strong putrid odour after 4 days.

  2. A cycle ergometer test of maximal aerobic power.

    Science.gov (United States)

    Myles, W S; Toft, R J

    1982-01-01

    An indirect test of maximal aerobic power (IMAP) was evaluated in 31 healthy male subjects by comparing it with a direct treadmill measurement of maximal aerobic power (VO2 max), with the prediction of VO2 max from heart rate during submaximal exercise on a cycle ergometer using Astrand's nomogram, with the British Army's Basic Fitness Test (BFT, a 2.4 km run performed in boots and trousers), and with a test of maximum anaerobic power. For the IMAP test, subjects pedalled on a cycle ergometer at 75 revs X min-1. The workload was 37.5 watts for the first minute, and was increased by 37.5 watts every minute until the subject could not continue. Time to exhaustion was recorded. Predicted VO2 max and times for BFT and IMAP correlated significantly (p less than 0.001) with the direct VO2 max: r = 0.70, r = 0.67 and r = 0.79 respectively. The correlation between direct VO2 max and the maximum anaerobic power test was significant (p less than 0.05) but lower, r = 0.44. Although lactate levels after direct VO2 max determination were significantly higher than those after the IMAP test, maximum heart rates were not significantly different. Submaximal VO2 values measured during the IMAP test yielded a regression equation relating VO2 and pedalling time. When individual values for direct and predicted VO2 max and times for BFT and IMAP were compared with equivalent standards, the percentages of subjects able to exceed the standard were 100, 65, 87, and 87 respectively. These data demonstrate that the IMAP test provides a valid estimate of VO2 max and indicate that it may be a practical test for establishing that an individual meets a minimum standard.

  3. Antibiogram study of aerobic bacterial isolates from uropathogens

    Directory of Open Access Journals (Sweden)

    Mallikarjuna Reddy C, Himabindu M, Maity Soumendranath, Kanta RC, Kapur Indu

    2014-04-01

    Full Text Available Background: Bacteria are capable of invading and infecting humans, leading to disease and sometimes death. Systems and tissues in human body are vulnerable to different organisms. Infection pattern is likely to differ by geographical regions. Aim: This study was aimed to isolate and identify the type of aerobic bacteria causing Urinary Tract Infections (UTI in different age groups and sexes, and also in some predisposing conditions. Their antibiogram also was done. Materials and Methods: Midstream urine sample collected aseptically from 276 patients were subjected for isolation and identification of aerobic bacteria by standard technique and subsequently antibiogram was done by Kirby –Bayer Method. Both sexes of patients with an age range of 10-70 years and patients with diabetes (22, hypertension (8 and anemia (8 were also included in the study. Results: Escherichia coli was the predominant organism(50% among other isolates – Klebsiella species (27.3%, Proteus species(7.14%, Staphylococcus saprophyticus (5.95%, Staphylococcus aureus (3.57%, Enterococci (3.57%, Pseudomonas species(2.38%. UTI was more common among patients of 60 and more years of age; however, incidence was more in female patients (36.2 – 38.5% compared with male patients (25-30%. Anemia, Diabetes and Hypertension conditions were found to predispose UTI. Aminoglycosides and Quinolones were found to be more effective against the isolates. Conclusion: The present study reveals in spite of the topographical diversity, the infecting bacterial isolates from this area were found to be the same as from any other part of India.

  4. Differences in aerobic fitness between inpatients and outpatients with severe mental disorders

    Directory of Open Access Journals (Sweden)

    Helene Daae-Qvale Holmemo

    2014-08-01

    Full Text Available AbstractBackgroundPatients with severe mental disorders have increased mortality, and cardiovascular disease (CVD accounts for a large part. Physical inactivity and low aerobic fitness have been recognized as significant risk factors for CVD. In this study, we investigated the differences in aerobic fitness and physical activity between in- and outpatients with severe mental disorders. Method and subjectsFifty in- and outpatients from a regional psychiatric department were included. The patients filled in a questionnaire on physical activity and completed a clinical examination. An estimation of aerobic fitness was calculated for each patient, using gender, age, waist circumference, resting heart rate and physical activity level as variables.ResultsInpatients had lower estimated aerobic fitness than outpatients (VO₂peak 42 vs 50 mL•kg-1•min-1, p<0.001. Compared to population data matched for age and gender, inpatients had lower aerobic fitness, while outpatients were not different from the population average.ConclusionInpatients at a psychiatric department had lower estimated aerobic fitness than outpatients, and a lower aerobic fitness compared to the general population. Our findings suggest that inpatients with severe mental disorders should be considered a high risk group for CVD.

  5. Kinetics of aerobic cometabolic biodegradation of chlorinated and brominated aliphatic hydrocarbons: A review.

    Science.gov (United States)

    Jesus, João; Frascari, Dario; Pozdniakova, Tatiana; Danko, Anthony S

    2016-05-15

    This review analyses kinetic studies of aerobic cometabolism (AC) of halogenated aliphatic hydrocarbons (HAHs) from 2001-2015 in order to (i) compare the different kinetic models proposed, (ii) analyse the estimated model parameters with a focus on novel HAHs and the identification of general trends, and (iii) identify further research needs. The results of this analysis show that aerobic cometabolism can degrade a wide range of HAHs, including HAHs that were not previously tested such as chlorinated propanes, highly chlorinated ethanes and brominated methanes and ethanes. The degree of chlorine mineralization was very high for the chlorinated HAHs. Bromine mineralization was not determined for studies with brominated aliphatics. The examined research period led to the identification of novel growth substrates of potentially high interest. Decreasing performance of aerobic cometabolism were found with increasing chlorination, indicating the high potential of aerobic cometabolism in the presence of medium- and low-halogenated HAHs. Further research is needed for the AC of brominated aliphatic hydrocarbons, the potential for biofilm aerobic cometabolism processes, HAH-HAH mutual inhibition and the identification of the enzymes responsible for each aerobic cometabolism process. Lastly, some indications for a possible standardization of future kinetic studies of HAH aerobic cometabolism are provided.

  6. Long-term aerobic exercise is associated with greater muscle strength throughout the life span.

    Science.gov (United States)

    Crane, Justin D; Macneil, Lauren G; Tarnopolsky, Mark A

    2013-06-01

    Aging is associated with a progressive decline in muscle strength, muscle mass, and aerobic capacity, which reduces mobility and impairs quality of life in elderly adults. Exercise is commonly employed to improve muscle function in individuals of all ages; however, chronic aerobic exercise is believed to largely impact cardiovascular function and oxidative metabolism, with minimal effects on muscle mass and strength. To study the effects of long-term aerobic exercise on muscle strength, we recruited 74 sedentary (SED) or highly aerobically active (ACT) men and women from within three distinct age groups (young: 20-39 years, middle: 40-64 years, and older: 65-86 years) and tested their aerobic capacity, isometric grip and knee extensor strength, and dynamic 1 repetition maximum knee extension. As expected, ACT subjects had greater maximal oxygen uptake and peak aerobic power output compared with SED subjects (p aerobic exercise appears to attenuate age-related reductions in muscle strength in addition to its cardiorespiratory and metabolic benefits.

  7. Aerobic capacity and disease activity in children, adolescents and young adults with juvenile idiopathic arthritis (JIA

    Directory of Open Access Journals (Sweden)

    van Pelt Philomien A

    2012-08-01

    Full Text Available Abstract Background As patients with juvenile idiopathic arthritis (JIA progress into adulthood, long-term outcome is determined by disease activity, physical and psychosocial development. Decreased aerobic capacity may play a critical role in health-related outcomes in JIA, since it has been linked with cardiovascular morbidity and mortality in late adulthood. The objectives of the current study are to examine the aerobic capacity and its relation to parameters of disease activity in children, adolescents and young adults with JIA. Methods Sixty-three patients with JIA (aged 10–27 years were cross sectional studied regarding their aerobic capacity and correlations were made to demographic, disease-related variables, and medication utilization. in a cross-sectional study group of 63 patients of all subtypes. Patients were divided in three age groups, 10–13 years; 14–17 years and 18–27 years. Results Reduced aerobic capacity is found in clinical remission as well as active disease in all subtypes and all age groups. Aerobic capacity is more impaired in active disease shown by DAS 28, JADAS 27, ESR and serum thrombocyte counts. Lower haemoglobin has a negative impact. Long-term used medication including methotrexate and corticosteroids didn’t influence outcome. There is no association with current sports participation. Conclusion Reduced aerobic capacity is present in children and adolescents with JIA, both in active disease and in patients with remission. Measures of aerobic capacity may serve as important outcome measure in JIA.

  8. Health-Promoting Effects of Serial vs. Integrated Combined Strength and Aerobic Training.

    Science.gov (United States)

    Karatrantou, K; Gerodimos, V; Häkkinen, K; Zafeiridis, A

    2017-01-01

    Combined strength and aerobic training programs are widely used for improving markers of physical fitness and health. We compared the efficiency of a serial and an integrated combined training program on health and overall fitness in middle-aged females. 54 females (46.7±4.5yrs) were assigned to a serial (SCG) or an integrated (ICG) combined training group or to a control group (CG). The SCG and ICG performed a 3-month training combining aerobic dance and calisthenics. The 2 training programs differ in the sequence of aerobic and strength exercises. SCG performed the strength exercises prior to aerobic; in ICG, the aerobic and strength exercises were altered in a predetermined order. Body composition/circumferences, blood pressure, respiratory function, flexibility, balance, muscle strength/endurance, power and aerobic capacity were measured before and after training. SCG and ICG significantly increased muscle strength and endurance, power, aerobic capacity, flexibility, balance, fat-free mass and respiratory function (ptraining. Serial and integrated combined training programs confer analogous adaptations and can be used interchangeably for counteracting the detrimental effects of sedentary lifestyle on indices of physical fitness and health.

  9. High Aerobic Capacity Mitigates Changes in the Plasma Metabolomic Profile Associated with Aging.

    Science.gov (United States)

    Falegan, Oluyemi S; Vogel, Hans J; Hittel, Dustin S; Koch, Lauren G; Britton, Steven L; Hepple, Russ T; Shearer, Jane

    2017-02-03

    Advancing age is associated with declines in maximal oxygen consumption. Declines in aerobic capacity not only contribute to the aging process but also are an independent risk factor for morbidity, cardiovascular disease, and all-cause mortality. Although statistically convincing, the relationships between aerobic capacity, aging, and disease risk remain largely unresolved. To this end, we employed sensitive, system-based metabolomics approach to determine whether enhanced aerobic capacity could mitigate some of the changes seen in the plasma metabolomic profile associated with aging. Metabolomic profiles of plasma samples obtained from young (13 month) and old (26 month) rats bred for low (LCR) or high (HCR) running capacity using proton nuclear magnetic resonance spectroscopy ((1)H NMR) were examined. Results demonstrated strong profile separation in old and low aerobic capacity rats, whereas young and high aerobic capacity rat models were less predictive. Significantly differential metabolites between the groups include taurine, acetone, valine, and trimethylamine-N-oxide among other metabolites, specifically citrate, succinate, isovalerate, and proline, were differentially increased in older HCR animals compared with their younger counterparts. When interactions between age and aerobic capacity were examined, results demonstrated that enhanced aerobic capacity could mitigate some but not all age-associated alterations in the metabolomic profile.

  10. Assessment of aerobic and respiratory growth in the Lactobacillus casei group.

    Directory of Open Access Journals (Sweden)

    Teresa Zotta

    Full Text Available One hundred eighty four strains belonging to the species Lactobacillus casei, L. paracasei and L. rhamnosus were screened for their ability to grow under aerobic conditions, in media containing heme and menaquinone and/or compounds generating reactive oxygen species (ROS, in order to identify respiratory and oxygen-tolerant phenotypes. Most strains were able to cope with aerobic conditions and for many strains aerobic growth and heme or heme/menaquinone supplementation increased biomass production compared to anaerobic cultivation. Only four L. casei strains showed a catalase-like activity under anaerobic, aerobic and respiratory conditions and were able to survive in presence of H2O2 (1 mM. Almost all L. casei and L. paracasei strains tolerated menadione (0.2 mM and most tolerated pyrogallol (50 mM, while L. rhamnosus was usually resistant only to the latter compound. This is the first study in which an extensive screening of oxygen and oxidative stress tolerance of members of the L. casei group has been carried out. Results allowed the selection of strains showing the typical traits of aerobic and respiratory metabolism (increased pH and biomass under aerobic or respiratory conditions and unique oxidative stress response properties. Aerobic growth and respiration may confer technological and physiological advantages in the L. casei group and oxygen-tolerant phenotypes could be exploited in several food industry applications.

  11. Aerobic conditions increase isoprenoid biosynthesis pathway gene expression levels for carotenoid production in Enterococcus gilvus.

    Science.gov (United States)

    Hagi, Tatsuro; Kobayashi, Miho; Nomura, Masaru

    2015-06-01

    Some lactic acid bacteria that harbour carotenoid biosynthesis genes (crtNM) can produce carotenoids. Although aerobic conditions can increase carotenoid production and crtNM expression levels, their effects on the pathways that synthesize carotenoid precursors such as mevalonate and isoprene are not completely understood. In this study, we investigated whether aerobic conditions affected gene expression levels involved in the isoprenoid biosynthesis pathway that includes the mevalonate and isoprene biosynthesis pathways in Enterococcus gilvus using real-time quantitative reverse transcription PCR. NADH oxidase (nox) and superoxide dismutase (sod) gene expression levels were investigated as controls for aerobic conditions. The expression levels of nox and sod under aerobic conditions were 7.2- and 8.0-fold higher, respectively, than those under anaerobic conditions. Aerobic conditions concomitantly increased the expression levels of crtNM carotenoid biosynthesis genes. HMG-CoA synthase gene expression levels in the mevalonate pathway were only slightly increased under aerobic conditions, whereas the expression levels of HMG-CoA reductase and five other genes in the isoprene biosynthesis pathways were 1.2-2.3-fold higher than those under anaerobic conditions. These results demonstrated that aerobic conditions could increase the expression levels of genes involved in the isoprenoid biosynthesis pathway via mevalonate in E. gilvus.

  12. Importance of extracellular proteins in maintaining structural integrity of aerobic granules.

    Science.gov (United States)

    Xiong, Yanghui; Liu, Yu

    2013-12-01

    Aerobic granules developed through self-immobilization of microorganisms are compact and structured microbial consortia embedded in a matrix of extracellular polymeric substances (EPS). This study investigated the contribution of extracellular proteins (PN) to maintaining the structural integrity of aerobic granule. It was found that hydrolysis of PN induced by Proteinase K led to significant disintegration of aerobic granules, whereas a substantial reduction of extracellular polysaccharides (PS) was also observed. It was proposed that hydrolysis of extracellular proteins present in the EPS matrix of aerobic granules led to collapse of the EPS matrix, and subsequent disintegration of aerobic granule. These suggested that extracellular proteins would be essential for maintaining structural stability of EPS matrix of aerobic granules. In addition, it was revealed that production of signaling molecules, such as autoinducer-2 (AI-2) and N-acyl homoserine lactones (AHLs) was also inhibited probably due to hydrolysis of quorum sensing receptor proteins by Proteinase K. This in turn provided an additional explanation for the observed Proteinase K-triggered dispersal of aerobic granules.

  13. Aerobic fitness predicts relational memory but not item memory performance in healthy young adults.

    Science.gov (United States)

    Baym, Carol L; Khan, Naiman A; Pence, Ari; Raine, Lauren B; Hillman, Charles H; Cohen, Neal J

    2014-11-01

    Health factors such as an active lifestyle and aerobic fitness have long been linked to decreased risk of cardiovascular disease, stroke, and other adverse health outcomes. Only more recently have researchers begun to investigate the relationship between aerobic fitness and memory function. Based on recent findings in behavioral and cognitive neuroscience showing that the hippocampus might be especially sensitive to the effects of exercise and fitness, the current study assessed hippocampal-dependent relational memory and non-hippocampal-dependent item memory in young adults across a range of aerobic fitness levels. Aerobic fitness was assessed using a graded exercise test to measure oxygen consumption during maximal exercise (VO2max), and relational and item memory were assessed using behavioral and eye movement measures. Behavioral results indicated that aerobic fitness was positively correlated with relational memory performance but not item memory performance, suggesting that the beneficial effects of aerobic fitness selectively affect hippocampal function and not that of the surrounding medial temporal lobe cortex. Eye movement results further supported the specificity of this fitness effect to hippocampal function, in that aerobic fitness predicted disproportionate preferential viewing of previously studied relational associations but not of previously viewed items. Potential mechanisms underlying this pattern of results, including neurogenesis, are discussed.

  14. [Formation Mechanism of Aerobic Granular Sludge and Removal Efficiencies in Integrated ABR-CSTR Reactor].

    Science.gov (United States)

    Wu, Kai-cheng; Wu, Peng; Xu, Yue-zhong; Li, Yue-han; Shen, Yao-liang

    2015-08-01

    Anaerobic Baffled Reactor (ABR) was altered to make an integrated anaerobic-aerobic reactor. The research investigated the mechanism of aerobic sludge granulation, under the condition of continuous-flow. The last two compartments of the ABR were altered into aeration tank and sedimentation tank respectively with seeded sludge of anaerobic granular sludge in anaerobic zone and conventional activated sludge in aerobic zone. The HRT was gradually decreased in sedimentation tank from 2.0 h to 0.75 h and organic loading rate was increased from 1.5 kg x (M3 x d)(-1) to 2.0 kg x (M3 x d)(-1) while the C/N of 2 was controlled in aerobic zone. When the system operated for 110 days, the mature granular sludge in aerobic zone were characterized by compact structure, excellent sedimentation performance (average sedimentation rate was 20.8 m x h(-1)) and slight yellow color. The system performed well in nitrogen and phosphorus removal under the conditions of setting time of 0.75 h and organic loading rate of 2.0 kg (m3 x d)(-1) in aerobic zone, the removal efficiencies of COD, NH4+ -N, TP and TN were 90%, 80%, 65% and 45%, respectively. The results showed that the increasing selection pressure and the high organic loading rate were the main propulsions of the aerobic sludge granulation.

  15. The influence of aerobic fitness status on ventilatory efficiency in patients with coronary artery disease

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    Danilo M.L. Prado

    2015-01-01

    Full Text Available OBJECTIVE: To test the hypotheses that 1 coronary artery disease patients with lower aerobic fitness exhibit a lower ventilatory efficiency and 2 coronary artery disease patients with lower initial aerobic fitness exhibit greater improvements in ventilatory efficiency with aerobic exercise training. METHOD: A total of 123 patients (61.0±0.7 years with coronary artery disease were divided according to aerobic fitness status into 3 groups: group 1 (n = 34, peak VO217.5 and 24.5 ml/kg/min. All patients performed a cardiorespiratory exercise test on a treadmill. Ventilatory efficiency was determined by the lowest VE/VCO2 ratio observed. The exercise training program comprised moderate-intensity aerobic exercise performed 3 times per week for 3 months. Clinicaltrials.gov: NCT02106533 RESULTS: Before intervention, group 1 exhibited both lower peak VO2 and lower ventilatory efficiency compared with the other 2 groups (p<0.05. After the exercise training program, group 1 exhibited greater improvements in aerobic fitness and ventilatory efficiency compared with the 2 other groups (group 1: ▵ = -2.5±0.5 units; group 2: ▵ = -0.8±0.3 units; and group 3: ▵ = -1.4±0.6 units, respectively; p<0.05. CONCLUSIONS: Coronary artery disease patients with lower aerobic fitness status exhibited lower ventilatory efficiency during a graded exercise test. In addition, after 3 months of aerobic exercise training, only the patients with initially lower levels of aerobic fitness exhibited greater improvements in ventilatory efficiency.

  16. Crop response of aerobic rice and winter wheat to nitrogen, phosphorus and potassium in a double cropping system

    OpenAIRE

    Dai, X.Q.; Zhang, H. Y.; Spiertz, J.H.J.; J. Yu; Xie, G.H.; Bouman, B.A.M.

    2010-01-01

    In the aerobic rice system, adapted rice cultivars are grown in non-flooded moist soil. Aerobic rice may be suitable for double cropping with winter wheat in the Huai River Basin, northern China plain. Field experiments in 2005 and 2006 were conducted to study the response of aerobic rice and winter wheat to sequential rates of nitrogen (N), phosphorus (P) and potassium (K) in aerobic rice—winter wheat (AR-WW) and winter wheat—aerobic rice (WW-AR) cropping sequences. Fertilizer treatments con...

  17. Impaired aerobic work capacity in insulin dependent diabetics with increased urinary albumin excretion

    DEFF Research Database (Denmark)

    Jensen, T; Richter, Erik; Feldt-Rasmussen, Bo;

    1988-01-01

    To assess whether decreased aerobic work capacity was associated with albuminuria in insulin dependent diabetics aerobic capacity was measured in three groups of 10 patients matched for age, sex, duration of diabetes, and degree of physical activity. Group 1 comprised 10 patients with normal...... were not explained by differences in metabolic control or the degree of autonomic neuropathy. Thus the insulin dependent diabetics with only slightly increased urinary albumin excretion had an appreciably impaired aerobic work capacity which could not be explained by autonomic neuropathy...

  18. Start up and operation of a pilot scale aerobic granular SBR

    Energy Technology Data Exchange (ETDEWEB)

    Morales, N.; Figueroa, M.; Val del Rio, A.; Mosquera-Corral, A.; Campos, J. L.; Mendez, R.

    2009-07-01

    The development of biomass in the form of aerobic granules is being recently under study as an improvement of conventional activated sludge system. Aerobic granules have been formed treating synthetic, municipal and industrial wastewaters in lab scale reactors, achieving good performances. The aim of this work is the study of the development and operation of aerobic granules in a pilot scale sequencing batch reactor (SBR). A SBR with a working volume of 100 L, an internal diameter of 30 cm and a useful height of 150 cm was used. (Author)

  19. Health-improving possibilities of usage of aerobics in the senior classes of comprehensive school.

    Directory of Open Access Journals (Sweden)

    Kravchuk T.N.

    2010-12-01

    Full Text Available In the article is opened health-improving possibilities of use of aerobics at physical training lessons in the senior classes. The technique of carrying out of lessons of physical training in the senior classes with use of different kinds of aerobics is proved and developed, and also their influence on indicators of health of senior pupils is investigated. It is shown that employment by aerobics promotes considerable improvement of health of senior pupils, increase of mood, state of health and activity.

  20. Aerobic Granulation in Sequencing Batch Reactor (SBR Treating Saline Wastewater

    Directory of Open Access Journals (Sweden)

    Ensieh Taheri

    2012-04-01

    Full Text Available Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background and Objectives: Aerobic sludge granulation is an advanced phenomenonin which its mechanisms have not been understood. Granulation can be a promising and novel biological wastewater treatment technology to eliminate organic and inorganic materials in future. High salinity is a parameter which leads to plasmolisatian and reduction of the cell activity. This could be a problem for biological treatment of the saline wastewater. Aerobic granule was formed and investigated during this study. Materials and Methods: This study is an intervention study on the treatment of wastewater with 500-10000 mg/L concentration of NaCl by sequencing batch reactor. Asynthesized wastewater including nutrient required for microorganism's growth was prepared. Input and output pH and EC were measured. Range of pH and DO varied between 7-8, and 2-5 mg/L, respectively. SEM technology was used to identify graduals properties.Results: In terms of color, granules divided into two groups of light brown and black. Granule ranged in 3-7mm with the sediment velocity of 0.9-1.35 m/s and density of 32-60 g/L.Properties of granules were varied. Filamentous bacteria and fungi were dominant in some granules. However non filamentous bacteria were dominant in others. EDX analysis indicated the presence of Ca and PO4.Conclusion: Granules with non filamentous bacterial were compact and settled faster. Presence of different concentrations of salinity leaded to plasmolysis of the bacterial cells and increased concentrations of EPS  in the system as a result  of which granulation accelerated. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso

  1. Environmental control on aerobic methane oxidation in coastal waters

    Science.gov (United States)

    Steinle, Lea; Maltby, Johanna; Engbersen, Nadine; Zopfi, Jakob; Bange, Hermann; Elvert, Marcus; Hinrichs, Kai-Uwe; Kock, Annette; Lehmann, Moritz; Treude, Tina; Niemann, Helge

    2016-04-01

    Large quantities of methane are produced in anoxic sediments of continental margins and may be liberated to the overlying water column, where some of it is consumed by aerobic methane oxidizing bacteria (MOB). Aerobic methane oxidation (MOx) in the water column is consequently the final sink for methane before its release to the atmosphere, where it acts as a potent greenhouse gas. In the context of the ocean's contribution to atmospheric methane, coastal seas are particularly important accounting >75% of global methane emission from marine systems. Coastal oceans are highly dynamic, in particular with regard to the variability of methane and oxygen concentrations as well as temperature and salinity, all of which are potential key environmental factors controlling MOx. To determine important environmental controls on the activity of MOBs in coastal seas, we conducted a two-year time-series study with measurements of physicochemical water column parameters, MOx activity and the composition of the MOB community in a coastal inlet in the Baltic Sea (Boknis Eck Time Series Station, Eckernförde Bay - E-Bay). In addition, we investigated the influence of temperature and oxygen on MOx during controlled laboratory experiments. In E-Bay, hypoxia developed in bottom waters towards the end of the stratification period. Constant methane liberation from sediments resulted in bottom water methane accumulations and supersaturation (with respect to the atmospheric equilibrium) in surface waters. Here, we will discuss the factors impacting MOx the most, which were (i) perturbations of the water column (ii) temperature and (iii) oxygen concentration. (i) Perturbations of the water column caused by storm events or seasonal mixing led to a decrease in MOx, probably caused by replacement of stagnant water with a high standing stock of MOB by 'new' waters with a lower abundance of methanotrophs. b) An increase in temperature generally led to higher MOx rates. c) Even though methane was

  2. Evaluation of the 3M™ Petrifilm™ Rapid Aerobic Count Plate for the Enumeration of Aerobic Bacteria: Collaborative Study, First Action 2015.13.

    Science.gov (United States)

    Bird, Patrick; Flannery, Jonathan; Crowley, Erin; Agin, James; Goins, David; Jechorek, Robert

    2016-05-01

    The 3M™ Petrifilm™ Rapid Aerobic Count (RAC) Plate is a sample-ready culture medium system containing dual-sensor indicator technology for the rapid quantification of aerobic bacteria in food products. The 3M Petrifilm RAC Plate was compared to the U.S. Food and Drug Administration Bacteriological Analytical Manual (FDA BAM) Chapter 3 (Aerobic Plate Count) for the enumeration of aerobic bacteria in raw easy-peel shrimp and the Standard Methods for the Examination of Dairy Products (SMEDP) Chapter 6 (Standard Plate Count Method) for the enumeration of aerobic bacteria in pasteurized skim milk and instant nonfat dry milk (instant NFDM). The 3M Petrifilm RAC Plate was evaluated using a paired study design in a multilaboratory collaborative study following current AOAC validation guidelines. Three target contamination levels (low, 10-100 CFU/g; medium, 100-1000 CFU/g; and high 1000-10 000 CFU/g) were evaluated for naturally occurring aerobic microflora for each matrix. For raw easy-peel shrimp, duplicate 3M Petrifilm RAC Plates were enumerated after 24 ± 2 h incubation at both 32 and 35°C. Pasteurized skim milk 3M Petrifilm RAC Plates were enumerated after 24 ± 2 h incubation at 32°C, and instant NFDM 3M Petrifilm RAC Plates were enumerated after 48 ± 3 h incubation at 32°C. No statistical difference was observed between 3M Petrifilm RAC Plate and FDA BAM or SMEDP reference methods for each contamination level.

  3. Sustainable polysaccharide-based biomaterial recovered from waste aerobic granular sludge as a surface coating material

    NARCIS (Netherlands)

    Lin, Y. M.; Nierop, K.G.J.; Girbal-Neuhauser, E.; Adriaanse, M.; van Loosdrecht, M. C M

    2015-01-01

    To evaluate the possibility of utilizing polysaccharide-based biomaterial recovered from aerobic granular sludge as a coating material, the morphology, molecular weight distribution and chemical composition of the recovered biomaterial were investigated by atomic force microscopy, size exclusion chr

  4. Aerobic glucose metabolism of Saccharomyces kluyveri: Growth, metabolite production, and quantification of metabolic fluxes

    DEFF Research Database (Denmark)

    Møller, Kasper; Christensen, B.; Förster, Jochen

    2002-01-01

    .29 +/- 0.01 g/g). The glucose metabolism of S. kluyveri was further characterized by the new and powerful techniques of metabolic network analysis. Flux distributions in the central carbon metabolism were estimated for respiro-fermentative growth in aerobic batch cultivation on glucose and respiratory...... at a constant specific rate of 0.12 g ethyl acetate per g dry weight per hour. The aerobic glucose metabolism in S. kluyveri was found to be less fermentative than in S. cerevisiae, as illustrated by the comparably low yield of ethanol on glucose (0.08 +/- 0.02 g/g), and high yield of biomass on glucose (0...... growth in aerobic glucose-limited continuous cultivation. It was found that in S. kluyveri the flux into the pentose phosphate pathway was 18.8 mmole per 100 mmole glucose consumed during respiratory growth in aerobic glucose-limited continuous cultivation. Such a low flux into the pentose phosphate...

  5. Long Term Effects on Risk Factors for Cardiovascular Disease after 12-Months of Aerobic Exercise Intervention

    DEFF Research Database (Denmark)

    Korshøj, Mette; Lidegaard, Mark; Krustrup, Peter;

    2016-01-01

    was to evaluate the 12-months effects of worksite aerobic exercise on risk factors for CVD among cleaners. METHODS: One hundred and sixteen cleaners aged 18-65 years were randomized to a group performing aerobic exercise and a reference group receiving lectures. Outcomes were collected at baseline and after 12......-months. A repeated measures 2×2 multi-adjusted mixed-model design was applied to compare the between-group differences using intention-to-treat analysis. RESULTS: Between-group differences (paerobic exercise group: cardiorespiratory fitness 2.15 (SE 1.03) mlO2/min...... to impose a notable adverse effect on resting and ambulatory blood pressure. CONCLUSION: This long-term worksite aerobic exercise intervention among cleaners led to several beneficial effects, but also potential adverse effects among those with high relative aerobic workloads. TRIAL REGISTRATION: Controlled...

  6. Recommended aerobic fitness level for metabolic health in children and adolescents: a study of diagnostic accuracy

    DEFF Research Database (Denmark)

    Adegboye, Amanda Ra; Anderssen, Sigmund A; Froberg, Karsten;

    2011-01-01

    Objective To define the optimal cut-off for low aerobic fitness and to evaluate its accuracy to predict clustering of risk factors for cardiovascular disease in children and adolescents. Design Study of diagnostic accuracy using a cross-sectional database. Setting European Youth Heart Study...... including Denmark, Portugal, Estonia and Norway. Participants 4500 schoolchildren aged 9 or 15 years. Main Outcome Measure Aerobic fitness was expressed as peak oxygen consumption relative to bodyweight (mlO(2)/min/kg). Results Risk factors included in the composite risk score (mean of z-scores) were...... would be expected by chance (AUC >0.5) for all cut-offs. Conclusions Aerobic fitness is easy to measure, and is an accurate tool for screening children with clustering of cardiovascular risk factors. Promoting physical activity in children with aerobic fitness level lower than the suggested cut...

  7. Adiposity, Aerobic Fitness, Muscle Fitness, and Markers of Inflammation in Children

    DEFF Research Database (Denmark)

    Steene-Johannessen, Jostein; Kolle, Elin; Andersen, Lars Bo;

    2013-01-01

    PURPOSE: The purpose of this study was to describe levels of inflammation markers in Norwegian children and to examine the associations of adiposity, aerobic fitness and muscle fitness with markers of inflammation. METHODS: In 2005-2006, 1467 9-year-olds wererandomly selected from all regions...... explosive, isometric and endurance strength. Aerobic fitness was measured directly during a maximal cycle ergometer test. Adiposity was expressed as waist circumference (WC). RESULTS: The girls had significantly higher levels of CRP, leptin, adiponectin and resistin and lower levels of TNF-α compared...... to the boys. We observed a graded association of CRP and leptin levels across quintiles of WC, aerobic fitness and muscle fitness (P ≤0.001 for all participants). The regression analyses revealed that WC, aerobic fitness and muscle fitness were independently associated with the CRP (WC β= 0.158, P

  8. The influence of preliminary aerobic treatment on the efficacy of waste stabilisation under leachate recirculation conditions

    Directory of Open Access Journals (Sweden)

    Monika Suchowska-Kisielewicz

    2014-12-01

    Full Text Available This article presents the changes in the chemical composition of leachate and the concentrations and quantity of methane production in each individual decomposition phases, determined for untreated and after aerobic treatment of waste stabilised in anaerobic reactors with and without leachate recirculation. The research results demonstrate that leachate recirculation intensifies the decomposition of both aerobically treated and untreated waste. The methane production in the reactor with untreated, stabilised waste with recirculation was 28% higher; and in the reactor with aerobically treated waste, the methane production was 24% higher than in the reactors without recirculation. An important finding of the study is that aerobic treatment of waste prior to landfilling effectively reduces the quantity of pollutant emissions in leachate and biogas from waste and increases the availability for methane micro-organisms of organic substrates from difficult-to-decompose organic substances.

  9. Influence of leachate recirculation on aerobic and anaerobic decomposition of solid wastes

    Energy Technology Data Exchange (ETDEWEB)

    Bilgili, M. Sinan [Yildiz Technical University, Environmental Engineering Department, 34349 Besiktas, Istanbul (Turkey)]. E-mail: mbilgili@yildiz.edu.tr; Demir, Ahmet [Yildiz Technical University, Environmental Engineering Department, 34349 Besiktas, Istanbul (Turkey)]. E-mail: ahmetd@yildiz.edu.tr; Ozkaya, Bestamin [Yildiz Technical University, Environmental Engineering Department, 34349 Besiktas, Istanbul (Turkey)]. E-mail: bozkaya@yildiz.edu.tr

    2007-05-08

    In this study, the effect of leachate recirculation on aerobic and anaerobic degradation of municipal solid wastes is determined by four laboratory-scale landfill reactors. The options studied and compared with the traditional anaerobic landfill are: leachate recirculation, landfill aeration, and aeration with leachate recirculation. Leachate quality is regularly monitored by the means of pH, alkalinity, total dissolved solids, conductivity, oxidation-reduction potential, chloride, chemical oxygen demand, ammonia, and total Kjeldahl nitrogen, in addition to generated leachate quantity. Aerobic leachate recirculated landfill appears to be the most effective option in the removal of organic matter and ammonia. The main difference between aerobic recirculated and non-recirculated landfill options is determined at leachate quantity. Recirculation is more effective on anaerobic degradation of solid waste than aerobic degradation. Further studies are going on to determine the optimum operational conditions for aeration and leachate recirculation rates, also with the operational costs of aeration and recirculation.

  10. Metal concentrations of simulated aerobic and anaerobic pilot scale landfill reactors

    Energy Technology Data Exchange (ETDEWEB)

    Sinan Bilgili, M. [Yildiz Technical University, Environmental Engineering Department, 34349 Yildiz, Besiktas, Istanbul (Turkey)]. E-mail: mbilgili@yildiz.edu.tr; Demir, Ahmet [Yildiz Technical University, Environmental Engineering Department, 34349 Yildiz, Besiktas, Istanbul (Turkey)]. E-mail: ahmetd@yildiz.edu.tr; Ince, Mahir [Department of Environmental Engineering, Gebze Institute of Technology, 41400 Gebze (Turkey)]. E-mail: mahirince@gyte.edu.tr; Ozkaya, Bestamin [Yildiz Technical University, Environmental Engineering Department, 34349 Yildiz, Besiktas, Istanbul (Turkey)]. E-mail: bozkaya@yildiz.edu.tr

    2007-06-25

    Leachate and solid waste samples from aerobic and anaerobic simulated landfill reactors operated with and without leachate recirculation were characterized in terms of metals such as Fe, Ca, K, Na, Cd, Cr, Cu, Pb, Ni, and Zn. Metal concentrations of aerobic landfill reactor leachate samples are always below the regulation limits. The higher concentrations in anaerobic landfill leachate samples decreased to regulation limits after the landfill becomes methanogenic. The effect of leachate recirculation is determined in anaerobic landfills more clearly than aerobic landfills. Metal precipitation resulted in a decrease in leachate metal content and an increase in solid waste metal content as expected. Result of the study show that the metal content of landfill leachate samples is not a major concern for both aerobic and anaerobic landfills.

  11. Lightweight and Compace Multifunction Computer-Controlled Strength and Aerobic Training Device Project

    Data.gov (United States)

    National Aeronautics and Space Administration — TDA Research proposes to develop a computer-controlled lightweight and compact device for aerobic and resistive training (DART) to counteract muscular atrophy and...

  12. Improving aerobic stability and biogas production of maize silage using silage additives.

    Science.gov (United States)

    Herrmann, Christiane; Idler, Christine; Heiermann, Monika

    2015-12-01

    The effects of air stress during storage, exposure to air at feed-out, and treatment with silage additives to enhance aerobic stability on methane production from maize silage were investigated at laboratory scale. Up to 17% of the methane potential of maize without additive was lost during seven days exposure to air on feed-out. Air stress during storage reduced aerobic stability and further increased methane losses. A chemical additive containing salts of benzoate and propionate, and inoculants containing heterofermentative lactic acid bacteria were effective to increase aerobic stability and resulted in up to 29% higher methane yields after exposure to air. Exclusion of air to the best possible extent and high aerobic stabilities should be primary objectives when ensiling biogas feedstocks.

  13. Interaction of Polybrominated Diphenyl Ethers and Aerobic Granular Sludge: Biosorption and Microbial Degradation

    Directory of Open Access Journals (Sweden)

    Shou-Qing Ni

    2014-01-01

    Full Text Available As a new category of persistent organic pollutants, polybrominated diphenyl ethers (PBDEs have become ubiquitous global environmental contaminants. No literature is available on the aerobic biotransformation of decabromodiphenyl ether (BDE-209. Herein, we investigated the interaction of PBDEs with aerobic granular sludge. The results show that the removal of BDE-209 from wastewater is mainly via biosorption onto aerobic granular sludge. The uptake capacity increased when temperature, contact time, and sludge dosage increased or solution pH dropped. Ionic strength had a negative influence on BDE-209 adsorption. The modified pseudo first-order kinetic model was appropriate to describe the adsorption kinetics. Microbial debromination of BDE-209 did not occur during the first 30 days of operation. Further study found that aerobic microbial degradation of 4,4′-dibromodiphenyl ether happened with the production of lower BDE congeners.

  14. Inlfuence of Marine Aerobic Bioiflms on Corrosion of 316L Stainless Steel

    Institute of Scientific and Technical Information of China (English)

    Feng-ling XU; Ji-zhou DUAN; Cun-guo LIN; Bao-rong HOU

    2015-01-01

    The inlfuence of marine aerobic bioiflms on the corrosion of 316L stainless steel (SS) in aerated and deaerated seawater was studied by electrochemical impedance spectroscopy (EIS), potentiodynamic polarisation curves, current-potential curves and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS). EIS and SEM-EDS results showed that the aero-bic bioiflms inhibited 316L SS corrosion within the test duration. Comparison of results under aerated and deaerated conditions revealed that O2 enhanced the inhibition efifciency of the aerobic bioiflms. This result indicated that living cells were necessary for the aerobic bioiflms to inhibit the corrosion of 316L SS. Polarization curves indicated that the bioiflms mainly inhibited anode ac-tion. Current-potential curves under deaerated conditions showed that electron transfer processes occurred between microorganisms and electrodes. Moreover, 316L SS as an electron acceptor was protected from corrosion.

  15. Physical health of young and middle age women under influence of step-aerobics exercises

    Directory of Open Access Journals (Sweden)

    Masliak I.P.

    2015-10-01

    Full Text Available Purpose: to determine the degree of step-aerobics exercises’ influence on 20-35 years age women’s health. Material: in the research 28 women of 20-35 years old age participated. Anthropometric indicators, heart beats rate in rest and after load (20 squats for 30 sec., blood pressure, vital capacity of lungs, hand dynamometry were registered. Results: level of physical health has been determined; influence of step-aerobics on women’s health has been found; age differences in the tested indicators have been analyzed. It was found out that step-aerobic trainings influence greatly on the following indicators: body mass, circumferential sizes and cardio vascular system; on functioning of respiratory system, strength of hand’s flexors and regulation of 31-35 years age women’s cardio-vascular system. Conclusions: application of step-aerobic exercises positively influenced on health of 20-35 years old women.

  16. Aerobics health as means of increasing somatic health of students of special medical group

    Directory of Open Access Journals (Sweden)

    Pivneva M.M.

    2013-08-01

    Full Text Available We prove the feasibility of employment by improving aerobic low intensity (LowImpact - heart rate in the range 128-140 beats / min, or 60-74% of HR max with students of special medical groups with disabilities cardiovascular system. The choice of three varieties of improving aerobics - classical, dance, tap dance - and with the help of laboratory experiment investigated the specificity of their effects on the physical health of students. According to the results of laboratory studies developed two versions of the author's method of application for improving aerobic physical education classes with students with disabilities but cardiac-vascular system, the main difference between them lies in the relationship and the manner of the classical sequence of exercises, dance, step aerobics. By comparing the results of educational experiments proved that both variants techniques contribute significantly improved key indicators of physical health subjects and thus are fairly equal in the nature of exposure.

  17. Anthropometry, somatotypes, and aerobic power in ballet, contemporary dance, and dancesport.

    Science.gov (United States)

    Liiv, Helena; Wyon, Matthew A; Jürimäe, Toivo; Saar, Meeli; Mäestu, Jarek; Jürimäe, Jaak

    2013-12-01

    This study compared anthropometric variables, somatotypes, and aerobic capacity between three groups of dancers: classical ballet dancers (M 33, F 56), contemporary dancers (M 28, F 109), and dancesport dancers (M 30, F 30). The assumption was that different functional requirements should produce differences in the anthropometric and aerobic capacity variables among the three groups. Anthropometric data for body mass index (BMI) and somatotypes were measured. Body fat percentage was measured by dual-energy x-ray absorptiometry. Maximal oxygen consumption and aerobic power were measured during an incremental treadmill test until exhaustion. Dancesport athletes were taller compared with same gender contemporary dancers (psomatotypes, and aerobic capacity, but we cannot say is it because of the training or selection or both.

  18. Aerobic fitness in children and young adults with primary ciliary dyskinesia

    DEFF Research Database (Denmark)

    Madsen, Astrid Hellerup; Green, Kent; Buchvald, Frederik

    2013-01-01

    patients. CONCLUSION: One-third of PCD patients exhibited substantially lower aerobic fitness than healthy subjects. Aerobic fitness correlated with FEV1, DLCO/VA and self-reported complaints of limitations in vigorous physical activity. These findings are most likely explained by PCD pulmonary disease...... and its impact on pulmonary function and physical ability. Considering fitness as an important outcome and including regular strenuous physical activity in PCD treatment would probably altogether increase pulmonary clearance, lung function, aerobic fitness, and quality of life, and prevent lifestyle......BACKGROUND: Although aerobic fitness is regarded as an overall prognostic measure of morbidity and mortality, its evaluation in the chronic progressive sinopulmonary disease primary ciliary dyskinesia (PCD) has been infrequently and inconsistently reported. Here we assessed peak oxygen uptake (VO2...

  19. Aerobic bacterial catabolism of persistent organic pollutants - potential impact of biotic and abiotic interaction.

    Science.gov (United States)

    Jeon, Jong-Rok; Murugesan, Kumarasamy; Baldrian, Petr; Schmidt, Stefan; Chang, Yoon-Seok

    2016-04-01

    Several aerobic bacteria possess unique catabolic pathways enabling them to degrade persistent organic pollutants (POPs), including polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polybrominated diphenylethers (PBDEs), and polychlorinated biphenyls (PCBs). The catabolic activity of aerobic bacteria employed for removal of POPs in the environment may be modulated by several biotic (i.e. fungi, plants, algae, earthworms, and other bacteria) and abiotic (i.e. zero-valent iron, advanced oxidation, and electricity) agents. This review describes the basic biochemistry of the aerobic bacterial catabolism of selected POPs and discusses how biotic and abiotic agents enhance or inhibit the process. Solutions allowing biotic and abiotic agents to exert physical and chemical assistance to aerobic bacterial catabolism of POPs are also discussed.

  20. Aerobic fitness in adolescents in southern Brazil: Association with sociodemographic aspects, lifestyle and nutritional status

    Directory of Open Access Journals (Sweden)

    D.A.S. Silva

    2016-03-01

    Conclusion: Thus, it was concluded that almost all adolescents show low aerobic fitness levels, which makes necessary effective interventions in the school environment with the promotion of sports and regular practice of physical activity.

  1. Six weeks' aerobic retraining after two weeks' immobilization restores leg lean mass and aerobic capacity but does not fully rehabilitate leg strenght in young and older men

    DEFF Research Database (Denmark)

    Vigelsø Hansen, Andreas; Gram, Martin; Wiuff, Caroline;

    2015-01-01

    OBJECTIVE: To determine the effect of aerobic retraining as rehabilitation after short-term leg immobilization on leg strength, leg work capacity, leg lean mass, leg muscle fibre type composition and leg capillary supply, in young and older men. SUBJECTS AND DESIGN: Seventeen young (23 ± 1 years...... immobilization had marked effects on leg strength, and work capacity and 6 weeks' retraining was sufficient to increase, but not completely rehabilitate, muscle strength, and to rehabilitate aerobic work capacity and leg lean mass (in the young men)....

  2. Integrated Anaerobic-Aerobic Biodegradation of Multiple Contaminants Including Chlorinated Ethylenes, Benzene, Toluene, and Dichloromethane.

    Science.gov (United States)

    Yoshikawa, Miho; Zhang, Ming; Toyota, Koki

    2017-01-01

    Complete bioremediation of soils containing multiple volatile organic compounds (VOCs) remains a challenge. To explore the possibility of complete bioremediation through integrated anaerobic-aerobic biodegradation, laboratory feasibility tests followed by alternate anaerobic-aerobic and aerobic-anaerobic biodegradation tests were performed. Chlorinated ethylenes, including tetrachloroethylene (PCE), trichloroethylene (TCE), cis-dichloroethylene (cis-DCE), and vinyl chloride (VC), and dichloromethane (DCM) were used for anaerobic biodegradation, whereas benzene, toluene, and DCM were used for aerobic biodegradation tests. Microbial communities involved in the biodegradation tests were analyzed to characterize the major bacteria that may contribute to biodegradation. The results demonstrated that integrated anaerobic-aerobic biodegradation was capable of completely degrading the seven VOCs with initial concentration of each VOC less than 30 mg/L. Benzene and toluene were degraded within 8 days, and DCM was degraded within 20 to 27 days under aerobic conditions when initial oxygen concentrations in the headspaces of test bottles were set to 5.3% and 21.0%. Dehalococcoides sp., generally considered sensitive to oxygen, survived aerobic conditions for 28 days and was activated during the subsequent anaerobic biodegradation. However, degradation of cis-DCE was suppressed after oxygen exposure for more than 201 days, suggesting the loss of viability of Dehalococcoides sp., as they are the only known anaerobic bacteria that can completely biodegrade chlorinated ethylenes to ethylene. Anaerobic degradation of DCM following previous aerobic degradation was complete, and yet-unknown microbes may be involved in the process. The findings may provide a scientific and practical basis for the complete bioremediation of multiple contaminants in situ and a subject for further exploration.

  3. Body composition changes associated with fasted versus non-fasted aerobic exercise

    OpenAIRE

    Schoenfeld, Brad Jon; Aragon, Alan Albert; Wilborn, Colin D; Krieger, James W.; Sonmez, Gul T

    2014-01-01

    It has been hypothesized that performing aerobic exercise after an overnight fast accelerates the loss of body fat. The purpose of this study was to investigate changes in fat mass and fat-free mass following four weeks of volume-equated fasted versus fed aerobic exercise in young women adhering to a hypocaloric diet. Twenty healthy young female volunteers were randomly assigned to 1 of 2 experimental groups: a fasted training (FASTED) group that performed exercise after an overnight fast (n ...

  4. Aerobic exercise modulates intracortical inhibition and facilitation in a nonexercised upper limb muscle

    OpenAIRE

    Singh, Amaya M; Duncan, Robin E; Neva, Jason L.; Staines, W. Richard

    2014-01-01

    Background Despite growing interest in the relationship between exercise and short-term neural plasticity, the effects of exercise on motor cortical (M1) excitability are not well studied. Acute, lower-limb aerobic exercise may potentially modulate M1 excitability in working muscles, but the effects on muscles not involved in the exercise are unknown. Here we examined the excitability changes in an upper limb muscle representation following a single session of lower body aerobic exercise. Inv...

  5. Differences in aerobic capacity among students with regard to their level of nutritional status

    Directory of Open Access Journals (Sweden)

    Mateja Kunješić

    2016-01-01

    Full Text Available Due to contemporary lifestyle, nutritional status of students is poorer and therefore it negatively affects the aerobic capacity. The purpose of this study was to determine the differences in aerobic capacity among female students of Faculty of Teacher Education with regard to their level of nutritional status. The study included 281 female students of the Faculty of Teacher Education, University of Zagreb. The sample of variables consisted of anthropometric measures: body height, body weight, sub-scapular and triceps skinfolds. Aerobic capacity was measured by 20 meter shuttle run test and nutritional status was determined by the body mass index (BMI. The subjects were divided into four groups according to their nutritional status: underweight, normal body weight, overweight and obese. Mean values of the BMI place the students into normal weight group, however, mean values of aerobic capacity show that students achieved poor results. Kruskal Wallis test and its post-hoc test (multiple comparisons for all groups with Bonferroni adjustment for determining the difference between subsamples according to the level of nutritional status among students show that the subsamples differ in four of the five variables that describe the morphological characteristics (body weight, BMI, sub-scapular skinfold, triceps skinfold as well as in aerobic capacity. The results obtained in this study show that the increased body mass have extremely high impact on the aerobic capacity results. It can be concluded that the tested students' aerobic capacity is poor and students with normal body weight have better aerobic capacity than overweight or obese students.

  6. Effects of exercise on functional aerobic capacity in lower limb osteoarthritis: a systematic review.

    Science.gov (United States)

    Escalante, Y; García-Hermoso, A; Saavedra, J M

    2011-05-01

    Osteoarthritis (OA) is a degenerative joint disease. The reduced aerobic capacity of patients with lower limb osteoarthritis affects their independence in performing everyday activities. The purpose of this systematic review was to summarize evidence for the effectiveness and structure of exercise programs on functional aerobic capacity (ability to perform activities of daily living that require sustained aerobic metabolism) in patients with hip and knee osteoarthritis. A computerized search was made of seven databases. Effect sizes (ES) and 95% confidence intervals (CI) were calculated, and the heterogeneity of the studies was assessed using Cochran's Q statistic applied to the ES means. The 20 studies that satisfied the inclusion criteria were selected for analysis. These studies were grouped into five categories according to the characteristics of the exercise program: land-based interventions (strength programs, tai chi, aerobic programs, mixed exercise programs) and aquatic intervention (hydrotherapy). The functional aerobic capacity improved in tai chi programs (ES=0.66; 95% CI, 0.23-1.09), aerobic programs (ES=0.90; 95% CI, 0.70-1.10), and mixed programs (ES=0.47; 95% CI, -0.38-0.39). The conclusions were: (i) despite recommendations for the use of exercise programs for aerobic fitness in patients with hip and knee osteoarthritis, few randomized clinical trials have been conducted; (ii) the structure of the exercise programs (program content and duration, and session frequency and duration) is very heterogeneous; (iii) overall, exercise programs based on tai chi, aerobic, and mixed exercise seem to give better results than hydrotherapy programs, but without the differences being altogether clear.

  7. Strength and Aerobic Exercises Improve Spatial Memory in Aging Rats Through Stimulating Distinct Neuroplasticity Mechanisms.

    Science.gov (United States)

    Vilela, Thais Ceresér; Muller, Alexandre Pastoris; Damiani, Adriani Paganini; Macan, Tamires Pavei; da Silva, Sabrina; Canteiro, Paula Bortoluzzi; de Sena Casagrande, Alisson; Pedroso, Giulia Dos Santos; Nesi, Renata Tiscoski; de Andrade, Vanessa Moraes; de Pinho, Ricardo Aurino

    2016-11-22

    Aging is associated with impaired cognition and memory and increased susceptibility to neurodegenerative disorders. Physical exercise is neuroprotective; however, the major evidence of this effect involves studies of only aerobic training in young animals. The benefits of other exercise protocols such as strength training in aged animals remains unknown. Here, we investigated the effect of aerobic and strength training on spatial memory and hippocampal plasticity in aging rats. Aging Wistar rats performed aerobic or strength training for 50 min 3 to 4 days/week for 8 weeks. Spatial memory and neurotrophic and glutamatergic signaling in the hippocampus of aged rats were evaluated after aerobic or strength training. Both aerobic and strength training improved cognition during the performance of a spatial memory task. Remarkably, the improvement in spatial memory was accompanied by an increase in synaptic plasticity proteins within the hippocampus after exercise training, with some differences in the intracellular functions of those proteins between the two exercise protocols. Moreover, neurotrophic signaling (CREB, BDNF, and the P75(NTR) receptor) increased after training for both exercise protocols, and aerobic exercise specifically increased glutamatergic proteins (NMDA receptor and PSD-95). We also observed a decrease in DNA damage after aerobic training. In contrast, strength training increased levels of PKCα and the proinflammatory factors TNF-α and IL-1β. Overall, our results show that both aerobic and strength training improved spatial memory in aging rats through inducing distinct molecular mechanisms of neuroplasticity. Our findings extend the idea that exercise protocols can be used to improve cognition during aging.

  8. Effects of aerobic exercise on hematologic indices of women with rheumatoid arthritis: A randomized clinical trial

    OpenAIRE

    2016-01-01

    Background: To investigate the effects of moderate aerobic exercise on the hemoglobin, hematocrit, and red blood cell (RBC) mass of women with rheumatoid arthritis (RA). Materials and Methods: This randomized clinical trial was conducted at the Specialized Clinic of Physical Medicine and Rehabilitation, Al-Zahra Hospital of Isfahan, during a 4-month period in 2014. We included patients with RA who did not have any malignancy and hematologic disorder. Two groups — one group receiving aerobic t...

  9. Effect of low-impact aerobic dance on the functional fitness of elderly women.

    Science.gov (United States)

    Hopkins, D R; Murrah, B; Hoeger, W W; Rhodes, R C

    1990-04-01

    To determine the effect of low-impact aerobic dance on sedentary elderly women (N = 53), functional fitness was measured by items from the proposed American Alliance of Health, Physical Education, Recreation, and Dance (AAHPERD) fitness test for older adults. After 12-weeks of low-impact aerobic dance, the group improved significantly on all functional fitness components except motor control/coordination, including cardiorespiratory endurance, strength/endurance, body agility, flexibility, body fat, and balance.

  10. Low intensity ultrasound stimulates biological activity of aerobic activated sludge

    Institute of Scientific and Technical Information of China (English)

    LIU Hong; YAN Yixin; WANG Wenyan; YU Yongyong

    2007-01-01

    This work aims to explore a procedure to improve biological wastewater treatment efficiency using low intensity ultrasound.The aerobic activated sludge from a municipal wastewater treatment plant was used as the experimental material.Oxygen uptake rate(OUR)of the activated sludge (AS)was determined to indicate the changes of AS activity stimulated by ultrasound at 35 kHZ for 0-40 min with ultrasonic intensities of 0-1.2 W/cm2.The highest OUR was observed at the ultrasonic intensity of 0.3 W/cm2 and an irradiation period of 10 min;more than 15% increase was achieved immediately after sonication.More significantly,the AS activity stimulated by ultrasound could last 24 h after sonication,and the AS activity achieved its peak value within 8 h after sonication.or nearly 100% higher than the initial level after sonication.Therefore,to improve the wastewater treatment efficiency of bioreactors,ultrasound with an intensity of 0.3 W/cm2 could be employed to irradiate a part of the AS in the bioreactor for 10 min every 8 h.

  11. Halophilic (aerobic) bacterial growth rate of mangrove ecosystem.

    Science.gov (United States)

    Khan, A Saleem; Ali, M Sheik; Baig, I Juned Ahmed

    2009-09-01

    Mangroves are woody specialized trees of tropics and are valuable flora contributing to economical, ecological, scientific and cultural resources. They thrive in salty environments like coastal regions and are aid towards disaster management facing the onslaught of giant waves such as Tsunami. Analysis of mangrove soil on the banks of the Adyar river behind the Theosophical society campus, Adyar, Chennai, India, gave a startling revelation of microorganisms that can tolerate different salinity ranges. Previous studies in Pichavaram delta, have reported bacterial isolates such as nitrogen fixing bacteria, halophiles and several others. However their efficiency in the growth of mangrove forest has been studied to a lesser extent. The present study has been designed and formulated to estimate halophilic (aerobic) bacterial load from mangroves soil sample based on depth and salinity of the soil and further the efficiency if any of these isolates in the growth of mangroves. Results have been correlated and a cohesive conclusion reached for further intensive research. This study throws light on the ecology of the bacterial population in the coastal marine environment inhabited bymangroves and its possible role in disaster mitigation.

  12. Aerobic exercise reduces blood pressure in resistant hypertension.

    Science.gov (United States)

    Dimeo, Fernando; Pagonas, Nikolaos; Seibert, Felix; Arndt, Robert; Zidek, Walter; Westhoff, Timm H

    2012-09-01

    Regular physical exercise is broadly recommended by current European and American hypertension guidelines. It remains elusive, however, whether exercise leads to a reduction of blood pressure in resistant hypertension as well. The present randomized controlled trial examines the cardiovascular effects of aerobic exercise on resistant hypertension. Resistant hypertension was defined as a blood pressure ≥140/90 mm Hg in spite of 3 antihypertensive agents or a blood pressure controlled by ≥4 antihypertensive agents. Fifty subjects with resistant hypertension were randomly assigned to participate or not to participate in an 8- to 12-week treadmill exercise program (target lactate, 2.0±0.5 mmol/L). Blood pressure was assessed by 24-hour monitoring. Arterial compliance and cardiac index were measured by pulse wave analysis. The training program was well tolerated by all of the patients. Exercise significantly decreased systolic and diastolic daytime ambulatory blood pressure by 6±12 and 3±7 mm Hg, respectively (P=0.03 each). Regular exercise reduced blood pressure on exertion and increased physical performance as assessed by maximal oxygen uptake and lactate curves. Arterial compliance and cardiac index remained unchanged. Physical exercise is able to decrease blood pressure even in subjects with low responsiveness to medical treatment. It should be included in the therapeutic approach to resistant hypertension.

  13. Effects of long-term aerobic exercise on EPOC.

    Science.gov (United States)

    LeCheminant, J D; Jacobsen, D J; Bailey, B W; Mayo, M S; Hill, J O; Smith, B K; Donnelly, J E

    2008-01-01

    This study sought to determine the influence of 16 months of progressive aerobic exercise on excess postexercise oxygen consumption (EPOC) and the extent EPOC contributed to weight management. Twenty-five overweight/obese women and 16 overweight/obese men participated in a 16-month exercise program (moderate-intensity treadmill walking) that progressed across the first 26 weeks to 5 days.wk(-1), 45 min.session(-1), and 75% HRR. Three-hour EPOC was measured at baseline, 9 months, and 16 months by indirect calorimetry in response to an exercise session (treadmill walking), in which energy expenditure (EE) was estimated from the participant's previous 10 exercise sessions. For women, EPOC was 7.5 +/- 4.9, 9.6 +/- 7.6, and 6.5 +/- 6.5 L at baseline, 9 months, and 16 months, respectively (p > 0.05). For men, EPOC increased from baseline (11.8 +/- 6.8 L) to 9 months (13.5 +/- 8.6 L) (p EPOC was correlated with change in EE at 9 months (r = 0.65; p EPOC in overweight/obese men but not women. Change in volume of exercise likely explained the increase in energy expenditure during EPOC in men. EPOC contributed modestly to EE compared to the exercise itself.

  14. Excess postexercise oxygen consumption after aerobic exercise training.

    Science.gov (United States)

    Sedlock, Darlene A; Lee, Man-Gyoon; Flynn, Michael G; Park, Kyung-Shin; Kamimori, Gary H

    2010-08-01

    Literature examining the effects of aerobic exercise training on excess postexercise oxygen consumption (EPOC) is sparse. In this study, 9 male participants (19-32 yr) trained (EX) for 12 wk, and 10 in a control group (CON) maintained normal activity. VO(2max), rectal temperature (T(re)), epinephrine, norepinephrine, free fatty acids (FFA), insulin, glucose, blood lactate (BLA), and EPOC were measured before (PRE) and after (POST) the intervention. EPOC at PRE was measured for 120 min after 30 min of treadmill running at 70% VO(2max). EX completed 2 EPOC trials at POST, i.e., at the same absolute (ABS) and relative (REL) intensity; 1 EPOC test for CON served as both the ABS and REL trial because no significant change in VO(2max) was noted. During the ABS trial, total EPOC decreased significantly (p EPOC during the REL trial; however, epinephrine was significantly lower, and norepinephrine and FFA, significantly higher, at endexercise after training. Results indicate that EPOC varies as a function of relative rather than absolute metabolic stress and that training improves the efficiency of metabolic regulation during recovery from exercise. Mechanisms for the decreased magnitude of EPOC in the ABS trial include decreases in BLA, T(re), and perhaps epinephrine-mediated hepatic glucose production and insulin-mediated glucose uptake.

  15. Genomics of aerobic cellulose utilization systems in actinobacteria.

    Directory of Open Access Journals (Sweden)

    Iain Anderson

    Full Text Available Cellulose degrading enzymes have important functions in the biotechnology industry, including the production of biofuels from lignocellulosic biomass. Anaerobes including Clostridium species organize cellulases and other glycosyl hydrolases into large complexes known as cellulosomes. In contrast, aerobic actinobacteria utilize systems comprised of independently acting enzymes, often with carbohydrate binding domains. Numerous actinobacterial genomes have become available through the Genomic Encyclopedia of Bacteria and Archaea (GEBA project. We identified putative cellulose-degrading enzymes belonging to families GH5, GH6, GH8, GH9, GH12, GH48, and GH51 in the genomes of eleven members of the actinobacteria. The eleven organisms were tested in several assays for cellulose degradation, and eight of the organisms showed evidence of cellulase activity. The three with the highest cellulase activity were Actinosynnema mirum, Cellulomonas flavigena, and Xylanimonas cellulosilytica. Cellobiose is known to induce cellulolytic enzymes in the model organism Thermobifida fusca, but only Nocardiopsis dassonvillei showed higher cellulolytic activity in the presence of cellobiose. In T. fusca, cellulases and a putative cellobiose ABC transporter are regulated by the transcriptional regulator CelR. Nine organisms appear to use the CelR site or a closely related binding site to regulate an ABC transporter. In some, CelR also regulates cellulases, while cellulases are controlled by different regulatory sites in three organisms. Mining of genome data for cellulose degradative enzymes followed by experimental verification successfully identified several actinobacteria species which were not previously known to degrade cellulose as cellulolytic organisms.

  16. AEROBIC BACTERIOLOGY OF CHRONIC SUPPURATIVE OTITIS MEDIA: OUR EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Mahesh V .

    2015-08-01

    Full Text Available Chronic Suppurative Otitis Media (CSOM is a condition of the middle ear that is characterized by persistent or recurrent discharge through a chronic perforation of the tympanic membrane from the middle ear cleft. Untreated cases of Chronic Suppurative Oti tis Media can result in a broad range of complications like mastoiditis, labyrinthitis, facial nerve paralysis and serious intracranial complications. In this study an attempt is made to know the aerobic bacteriology of Chronic Suppurative Otitis Media, wi th antimicrobial susceptibility testing of the bacterial isolates. The present prospective study was carried out on 50 patients presenting with Chronic Suppurative Otitis Media between January 2014 to December 2014 in the department of E.N.T, Basaveshwara Medical College Hospital and Research Centre, Chitradurga. The most common bacteria in Chronic Suppurative Otitis Media in this study was Pseudomonas aeruginosa (62% followed by Staphylococcus aureus (22%. Gentamicin was the most sensitive (100% antibio tic against Pseudomonas aeruginosa followed by Amikacin (96.77%. Ceftriaxone and Gentamicin were the most sensitive (100% antibiotic against Staphylococcus aureus followed by Amikacin (90.9%

  17. Physicochemical treatments of anionic surfactants wastewater: Effect on aerobic biodegradability.

    Science.gov (United States)

    Aloui, Fathi; Kchaou, Sonia; Sayadi, Sami

    2009-05-15

    The effect of different physicochemical treatments on the aerobic biodegradability of an industrial wastewater resulting from a cosmetic industry has been investigated. This industrial wastewater contains 11423 and 3148mgL(-1) of chemical oxygen demand (COD) and anionic surfactants, respectively. The concentration of COD and anionic surfactants were followed throughout the diverse physicochemical treatments and biodegradation experiments. Different pretreatments of this industrial wastewater using chemical flocculation process with lime and aluminium sulphate (alum), and also advanced oxidation process (electro-coagulation (Fe and Al) and electro-Fenton) led to important COD and anionic surfactants removals. The best results were obtained using electro-Fenton process, exceeding 98 and 80% of anionic surfactants and COD removals, respectively. The biological treatment by an isolated strain Citrobacter braakii of the surfactant wastewater, as well as the pretreated wastewater by the various physicochemical processes used in this study showed that the best results were obtained with electro-Fenton pretreated wastewater. The characterization of the treated surfactant wastewater by the integrated process (electro-coagulation or electro-Fenton)-biological showed that it respects Tunisian discharge standards.

  18. Aerobic cyanide degradation by bacterial isolates from cassava factory wastewater.

    Science.gov (United States)

    Kandasamy, Sujatha; Dananjeyan, Balachandar; Krishnamurthy, Kumar; Benckiser, Gero

    2015-01-01

    Ten bacterial strains that utilize cyanide (CN) as a nitrogen source were isolated from cassava factory wastewater after enrichment in a liquid media containing sodium cyanide (1 mM) and glucose (0.2% w/v). The strains could tolerate and grow in cyanide concentrations of up to 5 mM. Increased cyanide levels in the media caused an extension of lag phase in the bacterial growth indicating that they need some period of acclimatisation. The rate of cyanide removal by the strains depends on the initial cyanide and glucose concentrations. When initial cyanide and glucose concentrations were increased up to 5 mM, cyanide removal rate increased up to 63 and 61 per cent by Bacillus pumilus and Pseudomonas putida. Metabolic products such as ammonia and formate were detected in culture supernatants, suggesting a direct hydrolytic pathway without an intermediate formamide. The study clearly demonstrates the potential of aerobic treatment with cyanide degrading bacteria for cyanide removal in cassava factory wastewaters.

  19. Volatile dimethyl polonium produced by aerobic marine microorganisms.

    Science.gov (United States)

    Bahrou, Andrew S; Ollivier, Patrick R L; Hanson, Thomas E; Tessier, Emmanuel; Amouroux, David; Church, Thomas M

    2012-10-16

    The production of volatile polonium (Po(v)), a naturally occurring radioactive element, by pure cultures of aerobic marine tellurite-resistant microorganisms was investigated. Rhodotorula mucilaginosa, a carotogenic yeast, and a Bacillus sp. strain, a Gram-positive bacterium, generated approximately one and 2 orders of magnitude, respectively, greater amounts of Po(v) compared to the other organisms tested. Gas chromatography-inductively coupled plasma-mass spectrometry (GC-ICP-MS) analysis identified dimethyl polonide (DMPo) as the predominant volatile Po compound in culture headspace of the yeast. This species assignment is based on the exact relation between GC retention times and boiling points of this and other Group VI B analogues (S, Se, and Te). The extent of the biotic Po(v) production correlates exponentially with elevated particulate Po (Po(p)): dissolved Po (Po(aq)) ratios in the cultures, consistent with efficient Po bioaccumulation. Further experimentation demonstrated that some abiotic Po(v) generation is possible. However, high-level Po(v) generation in these cultures is predominantly biotic.

  20. Aerobic biodegradation of propylene glycol by soil bacteria.

    Science.gov (United States)

    Toscano, Giuseppe; Cavalca, Lucia; Letizia Colarieti, M; Scelza, Rosalia; Scotti, Riccardo; Rao, Maria A; Andreoni, Vincenza; Ciccazzo, Sonia; Greco, Guido

    2013-09-01

    Propylene glycol (PG) is a main component of aircraft deicing fluids and its extensive use in Northern airports is a source of soil and groundwater contamination. Bacterial consortia able to grow on PG as sole carbon and energy source were selected from soil samples taken along the runways of Oslo Airport Gardermoen site (Norway). DGGE analysis of enrichment cultures showed that PG-degrading populations were mainly composed by Pseudomonas species, although Bacteroidetes were found, as well. Nineteen bacterial strains, able to grow on PG as sole carbon and energy source, were isolated and identified as different Pseudomonas species. Maximum specific growth rate of mixed cultures in the absence of nutrient limitation was 0.014 h(-1) at 4 °C. Substrate C:N:P molar ratios calculated on the basis of measured growth yields are in good agreement with the suggested values for biostimulation reported in literature. Therefore, the addition of nutrients is suggested as a suitable technique to sustain PG aerobic degradation at the maximum rate by autochthonous microorganisms of unsaturated soil profile.

  1. Effect of Beetroot Juice Supplementation on Aerobic Response during Swimming

    Directory of Open Access Journals (Sweden)

    Marco Pinna

    2014-01-01

    Full Text Available The beneficial effects of beetroot juice supplementation (BJS have been tested during cycling, walking, and running. The purpose of the present study was to investigate whether BJS can also improve performance in swimmers. Fourteen moderately trained male master swimmers were recruited and underwent two incremental swimming tests randomly assigned in a pool during which workload, oxygen uptake (VO2, carbon dioxide production (VCO2, pulmonary ventilation (VE, and aerobic energy cost (AEC of swimming were measured. One was a control swimming test (CSW and the other a swimming test after six days of BJS (0.5l/day organic beetroot juice containing about 5.5 mmol of NO3−. Results show that workload at anaerobic threshold was significantly increased by BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS test respectively. Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5 during the SW test vs. 1.7 ± 0.3 kcal·kg−1·h−1 during the BJS test. The other variables lacked a statistically significant effect with BJS. The present investigation provides evidence that BJS positively affects performance of swimmers as it reduces the AEC and increases the workload at anaerobic threshold.

  2. Evaluation of an aerobic submerged filter packed with volcanic scoria.

    Science.gov (United States)

    Morgan-Sagastume, J M; Noyola, A

    2008-05-01

    An aerobic submerged filter (ASF) using volcanic scoria stones as packing media was evaluated. The wastewater used was a mixture of sewage with sugar to obtain organic matter concentrations between 28 and 3230 mg CODt/L, hydraulic rates up to 2.88 m3/m2 d and organic loading rates between 0.45 and 9.4 kg CODt/m3 d. The system removed 80% of CODt as average for organic loading rates between 0.45 and 3 kg CODt/m3 d and 54% at the higher rate (9.4 kg CODt/m3 d). It was not necessary to backwash the filters, a negligible pressure drop and a good biomass attachment in the volcanic scoria stones was observed. Nitrification and organic matter biodegradation were carried out simultaneously with a nitrate production of 90% up to 1.7kgCODt/m3 d. Tracer studies revealed a completed mixed hydraulic pattern which was not affected by the presence of biomass.

  3. Anaerobic growth of a "strict aerobe" (Bacillus subtilis).

    Science.gov (United States)

    Nakano, M M; Zuber, P

    1998-01-01

    There was a long-held belief that the gram-positive soil bacterium Bacillus subtilis is a strict aerobe. But recent studies have shown that B. subtilis will grow anaerobically, either by using nitrate or nitrite as a terminal electron acceptor, or by fermentation. How B. subtilis alters its metabolic activity according to the availability of oxygen and alternative electron acceptors is but one focus of study. A two-component signal transduction system composed of a sensor kinase, ResE, and a response regulator, ResD, occupies an early stage in the regulatory pathway governing anaerobic respiration. One of the essential roles of ResD and ResE in anaerobic gene regulation is induction of fnr transcription upon oxygen limitation. FNR is a transcriptional activator for anaerobically induced genes, including those for respiratory nitrate reductase, narGHJI.B. subtilis has two distinct nitrate reductases, one for the assimilation of nitrate nitrogen and the other for nitrate respiration. In contrast, one nitrite reductase functions both in nitrite nitrogen assimilation and nitrite respiration. Unlike many anaerobes, which use pyruvate formate lyase, B. subtilis can carry out fermentation in the absence of external electron acceptors wherein pyruvate dehydrogenase is utilized to metabolize pyruvate.

  4. Protons and pleomorphs: aerobic hydrogen production in Azotobacters.

    Science.gov (United States)

    Noar, Jesse D; Bruno-Bárcena, José M

    2016-02-01

    As obligate aerobic soil organisms, the ability of Azotobacter species to fix nitrogen is unusual given that the nitrogenase complex requires a reduced cellular environment. Molecular hydrogen is an unavoidable byproduct of the reduction of dinitrogen; at least one molecule of H2 is produced for each molecule of N2 fixed. This could be considered a fault in nitrogenase efficiency, essentially a waste of energy and reducing equivalents. Wild-type Azotobacter captures this hydrogen and oxidizes it with its membrane-bound uptake hydrogenase complex. Strains lacking an active hydrogenase complex have been investigated for their hydrogen production capacities. What is the role of H2 in the energy metabolism of nitrogen-fixing Azotobacter? Is hydrogen production involved in Azotobacter species' protection from or tolerance to oxygen, or vice versa? What yields of hydrogen can be expected from hydrogen-evolving strains? Can the yield of hydrogen be controlled or increased by changing genetic, environmental, or physiological conditions? We will address these questions in the following mini-review.

  5. The upper limit of aerobic power in humans.

    Science.gov (United States)

    Burtscher, Martin; Nachbauer, Werner; Wilber, Randall

    2011-10-01

    Data on the upper limit of aerobic power in humans are scarce. Thus, here we demonstrate extraordinarily high V'O(2)max and submaximal exercise performance in a young elite cross country skier (22 years, 170 cm, 63 kg; hemoglobin: 16.8 g/dL) who was evaluated before winning an Olympic gold medal. The test was performed during progressive roller-ski exercise on an outdoor uphill track (7-10% incline). The athlete demonstrated a V'O(2)max of 90.6 mL/min/kg (45 s average; 26 METs; 5.7 L/min). But even more impressive than V'O(2)max was his ability to exercise at a V'O(2) of 65 mL/min/kg (71.4% V'O(2)max) at a lactate level of 1.6 mmol/L. At the self-selected maximal lactate steady state he consumed 78 mLO(2)/min/kg (85.7% V'O(2)max) with a corresponding lactate level of 4.4 mmol/L. These values rank among the highest ever demonstrated in human beings.

  6. The training effects of dance aerobics: A review with an emphasis on the perspectives of investigations.

    Science.gov (United States)

    Zaletel, Petra; Gabrilo, Goran; Perić, Mia

    2013-05-01

    The training effects of contemporary aerobics programmes (hi lo, dance aerobics, step aerobics, aqua aerobics etc.) have been frequently investigated. However, we found no recent paper which reviewed aerobic programmes with regard to their training effectiveness, characteristics of the subjects involved, variables of interest and experimental design. In this paper we summarise the findings of more than 40 studies published in the 2000-2011 period that investigated the training effects of different forms of contemporary aerobics. In this review, the studies are grouped according to their characteristics (sample of subjects, variables of interest, study design, effects, etc.). Around 80% of the investigations dealt with females, with adults being most commonly observed. In the majority of investigations, the authors studied different variables at the same time (morphological anthropometric, motor, cardiovascular, biochemical indices, etc.). In recent studies a trend toward a psychological status examination is evident. In most instances positive training effects on motor-endurance and varsity of physiological variables are declared throughout a training period of 8 to 12 weeks. However, the positive changes in anaerobic endurance are not evidenced. Knowing the tendency of the overall increase of certain psychological disorders in population (including depression) there are indications that future, potentially highly interesting studies will deal with the psychological status of adults and older subjects.

  7. Relationships among traits of aerobic and anaerobic swimming performance in individual European sea bass Dicentrarchus labrax.

    Science.gov (United States)

    Marras, Stefano; Killen, Shaun S; Domenici, Paolo; Claireaux, Guy; McKenzie, David J

    2013-01-01

    Teleost fishes exhibit wide and temporally stable inter-individual variation in a suite of aerobic and anaerobic locomotor traits. One mechanism that could allow such variation to persist within populations is the presence of tradeoffs between aerobic and anaerobic performance, such that individuals with a high capacity for one type of performance have a reduced capacity for the other. We investigated this possibility in European seabass Dicentrarchuslabrax, each measured for a battery of indicators of maximum locomotor performance. Aerobic traits comprised active metabolic rate, aerobic scope for activity, maximum aerobic swimming speed, and stride length, using a constant acceleration test. Anaerobic traits comprised maximum speed during an escape response, maximum sprint speed, and maximum anaerobic burst speed during constant acceleration. The data provided evidence of significant variation in performance among individuals, but there was no evidence of any trade-offs among any traits of aerobic versus anaerobic swimming performance. Furthermore, the anaerobic traits were not correlated significantly among each other, despite relying on the same muscular structures. Thus, the variation observed may reflect trade-offs with other morphological, physiological or behavioural traits.

  8. Characteristics of a Novel Aerobic Denitrifying Bacterium, Enterobacter cloacae Strain HNR.

    Science.gov (United States)

    Guo, Long-Jie; Zhao, Bin; An, Qiang; Tian, Meng

    2016-03-01

    A novel aerobic denitrifier strain HNR, isolated from activated sludge, was identified as Enterobacter cloacae by16S rRNA sequencing analysis. Glucose was considered as the most favorable C-source for strain HNR. The logistic equation well described the bacterial growth, yielding a maximum growth rate (μmax) of 0.283 h(-1) with an initial NO3 (-)-N concentration of 110 mg/L. Almost all NO3 (-)-N was removed aerobically within 30 h with an average removal rate of 4.58 mg N L(-1) h(-1). Nitrogen balance analysis revealed that proximately 70.8 % of NO3 (-)-N was removed as gas products and only 20.7 % was transformed into biomass. GC-MS result indicates that N2 was the end product of aerobic denitrification. The enzyme activities of nitrate reductase and nitrite reductase, which are related to the process of aerobic denitrification, were 0.0688 and 0.0054 U/mg protein, respectively. Thus, the aerobic denitrification of reducing NO3 (-) to N2 by strain HNR was demonstrated. The optimal conditions for nitrate removal were C/N ratio 13, pH value 8, shaking speed 127 rpm and temperature 30 °C. These findings show that E. cloacae strain HNR has a potential application on wastewater treatment to achieve nitrate removal under aerobic conditions.

  9. Relationships among traits of aerobic and anaerobic swimming performance in individual European sea bass Dicentrarchus labrax.

    Directory of Open Access Journals (Sweden)

    Stefano Marras

    Full Text Available Teleost fishes exhibit wide and temporally stable inter-individual variation in a suite of aerobic and anaerobic locomotor traits. One mechanism that could allow such variation to persist within populations is the presence of tradeoffs between aerobic and anaerobic performance, such that individuals with a high capacity for one type of performance have a reduced capacity for the other. We investigated this possibility in European seabass Dicentrarchuslabrax, each measured for a battery of indicators of maximum locomotor performance. Aerobic traits comprised active metabolic rate, aerobic scope for activity, maximum aerobic swimming speed, and stride length, using a constant acceleration test. Anaerobic traits comprised maximum speed during an escape response, maximum sprint speed, and maximum anaerobic burst speed during constant acceleration. The data provided evidence of significant variation in performance among individuals, but there was no evidence of any trade-offs among any traits of aerobic versus anaerobic swimming performance. Furthermore, the anaerobic traits were not correlated significantly among each other, despite relying on the same muscular structures. Thus, the variation observed may reflect trade-offs with other morphological, physiological or behavioural traits.

  10. Optimizing intramuscular adaptations to aerobic exercise: effects of carbohydrate restriction and protein supplementation on mitochondrial biogenesis.

    Science.gov (United States)

    Margolis, Lee M; Pasiakos, Stefan M

    2013-11-01

    Mitochondrial biogenesis is a critical metabolic adaptation to aerobic exercise training that results in enhanced mitochondrial size, content, number, and activity. Recent evidence has shown that dietary manipulation can further enhance mitochondrial adaptations to aerobic exercise training, which may delay skeletal muscle fatigue and enhance exercise performance. Specifically, studies have demonstrated that combining carbohydrate restriction (endogenous and exogenous) with a single bout of aerobic exercise potentiates the beneficial effects of exercise on markers of mitochondrial biogenesis. Additionally, studies have demonstrated that high-quality protein supplementation enhances anabolic skeletal muscle intracellular signaling and mitochondrial protein synthesis following a single bout of aerobic exercise. Mitochondrial biogenesis is stimulated by complex intracellular signaling pathways that appear to be primarily regulated by 5'AMP-activated protein kinase and p38 mitogen-activated protein kinase mediated through proliferator-activated γ receptor co-activator 1 α activation, resulting in increased mitochondrial DNA expression and enhanced skeletal muscle oxidative capacity. However, the mechanisms by which concomitant carbohydrate restriction and dietary protein supplementation modulates mitochondrial adaptations to aerobic exercise training remains unclear. This review summarizes intracellular regulation of mitochondrial biogenesis and the effects of carbohydrate restriction and protein supplementation on mitochondrial adaptations to aerobic exercise.

  11. EFFECT OF HIGH & LOW INTENSITIES OF AEROBIC EXERCISE ON PHYSICAL FITNESS INDEX

    Directory of Open Access Journals (Sweden)

    Madhusudhan

    2015-06-01

    Full Text Available BACKGROUND: Aerobic exercise reduces body fat and improves weight control, increases HDL&Vo2 max. Also improves PFI (physical fitness index which is defined as ability to carry out daily tasks with vigour and alertness without undue fatigue. Though aerobic exercise is found to improve physical fitness, the relative merits of different intensities of aerobi c exercise in improving physical fitness is still uncertain. AIM: The present study was conducted to know the Effect of High & low intensity aerobic training on physical fitness index. MATERIALS & METHODS : 80 sedentary men (18 - 40 years were randomized in to 2 equal groups (High Intensity & low intensity group . The High [80% HR max] & Low intensity [50 % HR max] groups underwent aerobic exercise training using Bicycle ergo meter (COSCO at 900kpm & 540kpm, for 15mins/day & 30mins/day respectively, 5days a week, for a period of 14weeks. Physical fitness index of each subject was recorded by Modified Harvard step test before & after intervention. RESULTS : After 14 weeks of aerobic training both the exercise groups had improvement in PFI, but high intensity gr oup had a significant (p<0.05 improvement in PFI (97.18 - 101.14 than low intensity group (98.12 - 100.6. CONCLUSION : High intensity aerobic exercise is effective in improving physical fitness.

  12. Influence of aeration intensity on mature aerobic granules in sequencing batch reactor.

    Science.gov (United States)

    Gao, Da-Wen; Liu, Lin; Liang, Hong

    2013-05-01

    Aeration intensity is well known as an important factor in the formation of aerobic granules. In this research, two identical lab-scale sequencing batch reactors with aeration intensity of 0.8 (R1) and 0.2 m(3)/h (R2) were operated to investigate the characteristics and kinetics of matured aerobic granules. Results showed that both aeration intensity conditions induced granulation, but they showed different effects on the characteristics of aerobic granules. Compared with the low aeration intensity (R2), the aerobic granules under the higher aeration intensity (R1) had better physical characteristics and settling ability. However, the observed biomass yield (Y obs) in R1 [0.673 kg mixed liquor volatile suspended solids (MLVSS)/kg chemical oxygen demand (COD)] was lower than R2 (0.749 kg MLVSS/kg COD). In addition, the maximum specific COD removal rates (q max) and apparent half rate constant (K) of mature aerobic granular sludge under the two aeration intensities were at a similar level. Therefore, the matured aerobic granule system does not require to be operated in a higher aeration intensity, which will reduce the energy consumption.

  13. Nitrogen removal by Providencia rettgeri strain YL with heterotrophic nitrification and aerobic denitrification.

    Science.gov (United States)

    Ye, Jun; Zhao, Bin; An, Qiang; Huang, Yuan-Sheng

    2016-09-01

    Providencia rettgeri strain YL shows the capability of nitrogen removal under sole aerobic conditions. By using isotope ratio mass spectrometry, (15)N-labelled N2O and N2 were detected in aerobic batch cultures containing [Formula: see text], [Formula: see text] or [Formula: see text]. Strain YL converted [Formula: see text], [Formula: see text] and [Formula: see text] to produce more N2O than N2 in the presence of [Formula: see text]. An (15)N isotope tracing experiment confirmed that the nitrogen removal pathway of strain YL was heterotrophic nitrification-aerobic denitrification. The optimal treatment conditions for nitrogen removal were pH of 8, C/N ratio of 12, temperature of 25°C and shaking speed of 105 rpm. A continuous aerobic bioreactor inoculated with strain YL was developed. With an influent [Formula: see text] concentration of 90-200 mg/L, the [Formula: see text] removal efficiency ranged from 80% to 97% and the total nitrogen removal efficiency ranged from 72% to 95%. The nitrogen balance in the continuous bioreactor revealed that approximately 35-52% of influent [Formula: see text] was denitrified aerobically to form gaseous nitrogen. These findings show that the P. rettgeri strain YL has potential application in wastewater treatment for nitrogen removal under sole aerobic conditions.

  14. COD fractions of leachate from aerobic and anaerobic pilot scale landfill reactors

    Energy Technology Data Exchange (ETDEWEB)

    Bilgili, M. Sinan [Yildiz Technical University, Environmental Engineering Department, 34349 Besiktas, Istanbul (Turkey)], E-mail: mbilgili@yildiz.edu.tr; Demir, Ahmet [Yildiz Technical University, Environmental Engineering Department, 34349 Besiktas, Istanbul (Turkey)], E-mail: ahmetd@yildiz.edu.tr; Akkaya, Ebru [Yildiz Technical University, Environmental Engineering Department, 34349 Besiktas, Istanbul (Turkey)], E-mail: ekoca@yildiz.edu.tr; Ozkaya, Bestamin [Yildiz Technical University, Environmental Engineering Department, 34349 Besiktas, Istanbul (Turkey)], E-mail: bozkaya@yildiz.edu.tr

    2008-10-01

    One of the most important problems with designing and maintaining a landfill is managing leachate that generated when water passes through the waste. In this study, leachate samples taken from aerobic and anaerobic landfill reactors operated with and without leachate recirculation are investigated in terms of biodegradable and non-biodegradable fractions of COD. The operation time is 600 days for anaerobic reactors and 250 days for aerobic reactors. Results of this study show that while the values of soluble inert COD to total COD in the leachate of aerobic landfill with leachate recirculation and aerobic dry reactors are determined around 40%, this rate was found around 30% in the leachate of anaerobic landfill with leachate recirculation and traditional landfill reactors. The reason for this difference is that the aerobic reactors generated much more microbial products. Because of this condition, it can be concluded that total inert COD/total COD ratios of the aerobic reactors were 60%, whereas those of anaerobic reactors were 50%. This study is important for modeling, design, and operation of landfill leachate treatment systems and determination of discharge limits.

  15. The impact of nanoparticles on aerobic degradation of municipal solid waste.

    Science.gov (United States)

    Yazici Guvenc, Senem; Alan, Burcu; Adar, Elanur; Bilgili, Mehmet Sinan

    2017-04-01

    The amount of nanoparticles released from industrial and consumer products has increased rapidly in the last decade. These products may enter landfills directly or indirectly after the end of their useful life. In order to determine the impact of TiO2 and Ag nanoparticles on aerobic landfilling processes, municipal solid waste was loaded to three pilot-scale aerobic landfill bioreactors (80 cm diameter and 350 cm height) and exposed to TiO2 (AT) and Ag (AA) nanoparticles at total concentrations of 100 mg kg(-1) of solid waste. Aerobic landfill bioreactors were operated under the conditions about 0.03 L min(-1) kg(-1) aeration rate for 250 days, during which the leachate, solid waste, and gas characteristics were measured. The results indicate that there was no significant difference in the leachate characteristics, gas constituents, solid quality parameters, and temperature variations, which are the most important indicators of landfill operations, and overall aerobic degradation performance between the reactors containing TiO2 and Ag nanoparticles, and control (AC) reactor. The data also indicate that the pH levels, ionic strength, and the complex formation capacity of nanoparticles with Cl(-) ions can reduce the toxicity effects of nanoparticles on aerobic degradation processes. The results suggest that TiO2 and Ag nanoparticles at concentrations of 100 mg kg(-1) of solid waste do not have significant impacts on aerobic biological processes and waste management systems.

  16. The degradability of biodegradable plastics in aerobic and anaerobic waste landfill model reactors.

    Science.gov (United States)

    Ishigaki, Tomonori; Sugano, Wataru; Nakanishi, Akane; Tateda, Masafumi; Ike, Michihiko; Fujita, Masanori

    2004-01-01

    Degradabilities of four kinds of commercial biodegradable plastics (BPs), polyhydroxybutyrate and hydroxyvalerate (PHBV) plastic, polycaprolactone plastic (PCL), blend of starch and polyvinyl alcohol (SPVA) plastic and cellulose acetate (CA) plastic were investigated in waste landfill model reactors that were operated as anaerobically and aerobically. The application of forced aeration to the landfill reactor for supplying aerobic condition could potentially stimulate polymer-degrading microorganisms. However, the individual degradation behavior of BPs under the aerobic condition was completely different. PCL, a chemically synthesized BP, showed film breakage under the both conditions, which may have contributed to a reduction in the waste volume regardless of aerobic or anaerobic conditions. Effective degradation of PHBV plastic was observed in the aerobic condition, though insufficient degradation was observed in the anaerobic condition. But the aeration did not contribute much to accelerate the volume reduction of SPVA plastic and CA plastic. It could be said that the recalcitrant portions of the plastics such as polyvinyl alcohol in SPVA plastic and the highly substituted CA in CA plastic prevented the BP from degradation. These results indicated existence of the great variations in the degradability of BPs in aerobic and anaerobic waste landfills, and suggest that suitable technologies for managing the waste landfill must be combined with utilization of BPs in order to enhance the reduction of waste volume in landfill sites.

  17. Effect of Aerobic Exercise Training on Chinese Population with Mild to Moderate Depression in Hong Kong

    Directory of Open Access Journals (Sweden)

    Cassandra W. H. Ho

    2014-01-01

    Full Text Available Background. Exercise has been suggested to be a viable treatment for depression. This study investigates the effect of supervised aerobic exercise training on depressive symptoms and physical performance among Chinese patients with mild to moderate depression in early in-patient phase. Methods. A randomized repeated measure and assessor-blinded study design was used. Subjects in aerobic exercise group received 30 minutes of aerobic training, five days a week for 3 weeks. Depressive symptoms (MADRS and C-BDI and domains in physical performance were assessed at baseline and program end. Results. Subjects in aerobic exercise group showed a more significant reduction in depressive scores (MADRS as compared to control (between-group mean difference = 10.08 ± 9.41; P=0.026 after 3 weeks training. The exercise group also demonstrated a significant improvement in flexibility (between-group mean difference = 4.4 ± 6.13; P=0.02. Limitations. There was lack of longitudinal followup to examine the long-term effect of aerobic exercise on patients with depression. Conclusions. Aerobic exercise in addition to pharmacological intervention can have a synergistic effect in reducing depressive symptoms and increasing flexibility among Chinese population with mild to moderate depression. Early introduction of exercise training in in-patient phase can help to bridge the gap of therapeutic latency of antidepressants during its nonresponse period.

  18. Degradation of municipal solid waste in simulated landfill bioreactors under aerobic conditions.

    Science.gov (United States)

    Slezak, Radoslaw; Krzystek, Liliana; Ledakowicz, Stanislaw

    2015-09-01

    In this study the municipal solid waste degradation processes in simulated landfill bioreactors under aerobic and anaerobic conditions is investigated. The effect of waste aeration on the dynamics of the aerobic degradation processes in lysimeters as well as during anaerobic processes after completion of aeration is presented. The results are compared with the anaerobic degradation process to determine the stabilization stage of waste in both experimental modes. The experiments in aerobic lysimeters were carried out at small aeration rate (4.41⋅10(-3)lmin(-1)kg(-1)) and for two recirculation rates (24.9 and 1.58lm(-3)d(-1)). The change of leachate and formed gases composition showed that the application of even a small aeration rate favored the degradation of organic matter. The amount of CO2 and CH4 released from anaerobic lysimeter was about 5 times lower than that from the aerobic lysimeters. Better stabilization of the waste was obtained in the aerobic lysimeter with small recirculation, from which the amount of CO2 produced was larger by about 19% in comparison with that from the aerobic lysimeter with large leachate recirculation.

  19. Interaction between serum BDNF and aerobic fitness predicts recognition memory in healthy young adults.

    Science.gov (United States)

    Whiteman, Andrew S; Young, Daniel E; He, Xuemei; Chen, Tai C; Wagenaar, Robert C; Stern, Chantal E; Schon, Karin

    2014-02-01

    Convergent evidence from human and non-human animal studies suggests aerobic exercise and increased aerobic capacity may be beneficial for brain health and cognition. It is thought growth factors may mediate this putative relationship, particularly by augmenting plasticity mechanisms in the hippocampus, a brain region critical for learning and memory. Among these factors, glucocorticoids, brain derived neurotrophic factor (BDNF), insulin-like growth factor-1 (IGF-1), and vascular endothelial growth factor (VEGF), hormones that have considerable and diverse physiological importance, are thought to effect normal and exercise-induced hippocampal plasticity. Despite these predictions, relatively few published human studies have tested hypotheses that relate exercise and fitness to the hippocampus, and none have considered the potential links to all of these hormonal components. Here we present cross-sectional data from a study of recognition memory; serum BDNF, cortisol, IGF-1, and VEGF levels; and aerobic capacity in healthy young adults. We measured circulating levels of these hormones together with performance on a recognition memory task, and a standard graded treadmill test of aerobic fitness. Regression analyses demonstrated BDNF and aerobic fitness predict recognition memory in an interactive manner. In addition, IGF-1 was positively associated with aerobic fitness, but not with recognition memory. Our results may suggest an exercise adaptation-related change in the BDNF dose-response curve that relates to hippocampal memory.

  20. A new ventilatory threshold equation for aerobically trained men and women.

    Science.gov (United States)

    Malek, Moh H; Coburn, Jared W

    2009-04-01

    The purposes of the present study were to (i) modify previously published ventilatory threshold (VT) equations using the constant error (CE) values for aerobically trained individuals from a recent study; (ii) cross-validate the modified equations to determine their accuracy for estimating VT in aerobically trained individuals; (iii) derive a new non-exercise based equation for estimating VT in aerobically trained individuals if the modified equations are found to be inaccurate; and (iv) cross-validate the new VT equation using the Predicted REsidual Sum of Squares (PRESS) statistic and an independent sample of aerobically trained individuals. Two hundred and eight (n = 208) aerobically trained men and women (mean +/- SD: age = 38.8 +/- 10.4 year) performed a maximal incremental test on a cycle ergometer to determine the observed VT. The predicted VT values from seven published equations were compared with the observed VT by examining the CE, standard error of estimate, validity coefficient (r), and total error (TE). Cross-validation of the modified equations resulted in high %TE values. Therefore, a new VT equation was derived. Cross-validation of this equation on an independent sample of 72 subjects resulted in a low %TE value. The new model is recommended over previous models for estimating VT in aerobically trained individuals.

  1. Parallel pathways of ethoxylated alcohol biodegradation under aerobic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Zembrzuska, Joanna, E-mail: Joanna.Zembrzuska@put.poznan.pl; Budnik, Irena, E-mail: Irena.Budnik@gmail.com; Lukaszewski, Zenon, E-mail: zenon.lukaszewski@put.poznan.pl

    2016-07-01

    Non-ionic surfactants (NS) are a major component of the surfactant flux discharged into surface water, and alcohol ethoxylates (AE) are the major component of this flux. Therefore, biodegradation pathways of AE deserve more thorough investigation. The aim of this work was to investigate the stages of biodegradation of homogeneous oxyethylated dodecanol C{sub 12}E{sub 9} having 9 oxyethylene subunits, under aerobic conditions. Enterobacter strain Z3 bacteria were chosen as biodegrading organisms under conditions with C{sub 12}E{sub 9} as the sole source of organic carbon. Bacterial consortia of river water were used in a parallel test as an inoculum for comparison. The LC-MS technique was used to identify the products of biodegradation. Liquid-liquid extraction with ethyl acetate was selected for the isolation of C{sub 12}E{sub 9} and metabolites from the biodegradation broth. The LC-MS/MS technique operating in the multiple reaction monitoring (MRM) mode was used for quantitative determination of C{sub 12}E{sub 9}, C{sub 12}E{sub 8}, C{sub 12}E{sub 7} and C{sub 12}E{sub 6}. Apart from the substrate, the homologues C{sub 12}E{sub 8}, C{sub 12}E{sub 7} and C{sub 12}E{sub 6}, being metabolites of C{sub 12}E{sub 9} biodegradation by shortening of the oxyethylene chain, as well as intermediate metabolites having a carboxyl end group in the oxyethylene chain (C{sub 12}E{sub 8}COOH, C{sub 12}E{sub 7}COOH, C{sub 12}E{sub 6}COOH and C{sub 12}E{sub 5}COOH), were identified. Poly(ethylene glycols) (E) having 9, 8 and 7 oxyethylene subunits were also identified, indicating parallel central fission of C{sub 12}E{sub 9} and its metabolites. Similar results were obtained with river water as inoculum. It is concluded that AE, under aerobic conditions, are biodegraded via two parallel pathways: by central fission with the formation of PEG, and by Ω-oxidation of the oxyethylene chain with the formation of carboxylated AE and subsequent shortening of the oxyethylene chain by a

  2. Aerobic Methane Generation From Plants (AMP)? Yes, Mostly!

    Science.gov (United States)

    Whiticar, M. J.; Ednie, A. C.

    2007-12-01

    In 2006, Keppler et al. (K) published an intriguing and revolutionary idea that aerobic methane is produced in plants (AMP) and released to the atmosphere. Their initial scaling calculations estimated the amount of AMP fluxing from living plants to range from 62-236 Tg/y and 1-7 Tg/y for plant litter. Houweling et al. (2006) (H) refined this flux to ca. 85 Tg/y PIH and 125 Tg/y present day. More recently, Dueck et al. (2007) (D) challenged the claim of AMP from intact plants. Their experiments cited "...No evidence for substantial aerobic methane emission by terrestrial plants..." (max. 0.4 ng/g h-1). Due to the significance of AMP in understanding present and palaeo-atmospheric budgets (e.g., Whiticar and Schaefer, 2007), we conducted a wide range of experiments to confirm or refute the existence and magnitude of AMP. For explanation, experiments of K were time-series batch samples measured by gas chromatography on purged and ambient samples, whereas D used continuous-flow cuvettes and measured by optical PAS with time series single injections. Our longer-term experiments with corn, wheat, tomato, red cedar, chestnut, moss and lichen (3-97 h, 32 °C) used a plant chamber, flow-through system with a GYRO, an optical spectrometer that enables continuous 1 Hz CH4 measurements with a precision of ca. 1 ppbv. We conducted over 100 chamber experiments on sterilized and non-sterilized (Cs-137 radiation) samples of: 1) intact living plants (IP), 2) fresh leaves (FL) and 3) dried leaves (DL); under both 1) high and 2) low light conditions (HL, LL), and with 1) ambient CH4 (AM, ca. 1.92 ppmv) and 2) purged methane (PM, 10 and 96 ppbv) levels. Our results demonstrate that IP-AMs have CH4 flux rates of 0.74-3.48 ng/g h-1. In contrast, IP-PMs show intense CH4 uptake rates of -28.5 to -57.9 ng/g h-1 (substantially different than K's reported emissions of 12-370 ng/g h-1 values). Our FL-AM-LL have CH4 flux rates of 0.36-2.05 ng/g h-1, whereas FL-AM-HL have significant CH4

  3. Comparison of two field tests to estimate maximum aerobic speed.

    Science.gov (United States)

    Berthoin, S; Gerbeaux, M; Turpin, E; Guerrin, F; Lensel-Corbeil, G; Vandendorpe, F

    1994-08-01

    The measurement of maximal aerobic speed (MAS) and the prediction of maximal oxygen uptake (VO2 max) by means of field tests were carried out on 17 students studying physical education. The subjects underwent a continuous multi-stage track test (Léger and Boucher, 1980), shuttle test (Léger et al., 1984) and VO2 max measurement on a treadmill. The VO2 max values estimated using the track test (56.8 +/- 5.8 ml kg-1 min-1) were not significantly different from the values measured in the treadmill test (56.8 +/- 7.1 ml kg-1 min-1), but were higher than those estimated using the shuttle test (51.1 +/- 5.9 ml kg-1 min-1). The maximal nature of the tests was checked by measurement of heart rate and lactate concentration, taken within 2 min post-test. The means of the MAS observed in the track test (15.8 +/- 1.9 km h-1) and in the treadmill test (15.9 +/- 2.6 km h-1) were not significantly different (P > 0.10). The mean of the shuttle test MAS (13.1 +/- 1 km h-1) was significantly lower (P < 0.01) than those of the other tests. However, the MAS of the shuttle test and track test are linked. The equation for linear regression between MAS values in these two tests is MAStrack = 1.81 x MASshuttle -7.86 (r = 0.91), allowing estimation of one of these MAS values when the other is known. Thus these values may be used within diversified training.

  4. The influence of childhood aerobic fitness on learning and memory.

    Directory of Open Access Journals (Sweden)

    Lauren B Raine

    Full Text Available INTRODUCTION: There is a growing trend of inactivity among children, which may not only result in poorer physical health, but also poorer cognitive health. Previous research has shown that lower fitness has been related to decreased cognitive function for tasks requiring perception, memory, and cognitive control as well as lower academic achievement. PURPOSE: To investigate the relationship between aerobic fitness, learning, and memory on a task that involved remembering names and locations on a fictitious map. Different learning strategies and recall procedures were employed to better understand fitness effects on learning novel material. METHODS: Forty-eight 9-10 year old children (n = 24 high fit; HF and n = 24 low fit; LF performed a task requiring them to learn the names of specific regions on a map, under two learning conditions in which they only studied (SO versus a condition in which they were tested during study (TS. The retention day occurred one day after initial learning and involved two different recall conditions: free recall and cued recall. RESULTS: There were no differences in performance at initial learning between higher fit and lower fit participants. However, during the retention session higher fit children outperformed lower fit children, particularly when the initial learning strategy involved relatively poor recall performance (i.e., study only versus test-study strategy. CONCLUSIONS: We interpret these novel data to suggest that fitness can boost learning and memory of children and that these fitness-associated performance benefits are largest in conditions in which initial learning is the most challenging. Such data have important implications for both educational practice and policy.

  5. Aerobic Microbial Skin Flora in Jeddah City, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Rajaa M. Milyani

    2001-12-01

    Full Text Available The aerobic microbial skin flora of 40 healthy subjects living in Jeddah city (Saudi Arabia was determined. Two age groups: children and adults; including males and females were investigated. Seven sites were studied: forehead, axilla, chest, groin, leg, toe web and anterior nares. The skin was sampled by rubbing the chosen site with a surfactant substance (Tween 80 moistened cotton swab which was dipped back in the surfactant container and the resulted suspension was agitated for one minute. Thirty three microbial species were isolated from the seven sites of the study group, in which Acinetobacter baumannii, Acinetobacter lwoffii, corynebacterium species and Staphylococcus (Staph. aureus dominated among children (30% each. The most other prevalent isolates recovered were Alkaligenes species, Bacillus species, Chryseomonas luteola, Staph. epidermidis, Enterococcus faecalis and Staph. hominis (27.5% each. Organisms including Candida albicans, Enterobacter agglomerans, Escherichia coli, Flavobacterium meningosepticum, Klebsiella oxytoca, Micrococcus luteus, Micrococcus roseus, Micrococcus varians, Micrococcus species, Burkholderia cepacia, Stenotrophomonas maltophilia, Pseudomonas paucimobilis, Pseudomonas fluorescence, Pseudomonas species, Staph. capitis, Staph. cohnii, Staph. saprophyticus, Staph. simulans, Staph. warneri, Staph. xylosus, viridans-type streptococcus and yeasts were also found in different percentage. Higher isolation rates of Acinetobacter lwoffii, Staph. aureus, Alkaligenes species, Corynebacterium species, Chryseomonas luteola, Enterobacter agglomerans, Staph. epidermidis and other coagulase negative Staphylococci were noted in children from the seven sites. However, Chryseomonas luteola, and Pseudomonas species, were found only in the groin area among males. Otherwise, no significant differences were recorded in the isolation rates from each site separately in relation to age and sex. The role of the isolated microorganisms

  6. Aerobic degradation and photolysis of tylosin in water and soil.

    Science.gov (United States)

    Hu, Dingfei; Coats, Joel R

    2007-05-01

    Veterinary antibiotics enter the environment through the application of organic fertilizers to cropland. In this study, the aerobic degradation of tylosin, a widely used antibiotic in the production of livestock and poultry, was conducted in water and in soil in an effort to further investigate its environmental fate. Tylosin is a macrolide antibiotic, which consists of four factors (A, B, C, D). Water and soil were sampled at selected times and analyzed for tylosin and its degradation products by high-performance liquid chromatography (HPLC), with product identification confirmed by HPLC-mass spectrometry. Tylosin A is degraded with a half-life of 200 d in the light in water, and the total loss of tylosin A in the dark is 6% of the initial spiked amount during the experimental period. Tylosin C and D are relatively stable except in ultrapure water in the light. Slight increases of tylosin B after two months and formation of two photoreaction isomers of tylosin A were observed under exposure to light. However, tylosin probably would degrade faster if the experimental containers did not prevent ultraviolet transmission. In soil, tylosin A has a dissipation half-life of 7 d, and tylosin D is slightly more stable, with a dissipation half-life of 8 d in unsterilized and sterilized soil. Sorption and abiotic degradation are the major factors influencing the loss of tylosin in the environment, and no biotic degradation was observed at the test concentration either in pond water or in an agronomic soil, as determined by comparing dissipation profiles in sterilized and unsterilized conditions.

  7. A single bout of aerobic exercise promotes motor cortical neuroplasticity.

    Science.gov (United States)

    McDonnell, Michelle N; Buckley, Jonathan D; Opie, George M; Ridding, Michael C; Semmler, John G

    2013-05-01

    Regular physical activity is associated with enhanced plasticity in the motor cortex, but the effect of a single session of aerobic exercise on neuroplasticity is unknown. The aim of this study was to compare corticospinal excitability and plasticity in the upper limb cortical representation following a single session of lower limb cycling at either low or moderate intensity, or a control condition. We recruited 25 healthy adults to take part in three experimental sessions. Cortical excitability was examined using transcranial magnetic stimulation to elicit motor-evoked potentials in the right first dorsal interosseus muscle. Levels of serum brain-derived neurotrophic factor and cortisol were assessed throughout the experiments. Following baseline testing, participants cycled on a stationary bike at a workload equivalent to 57% (low intensity, 30 min) or 77% age-predicted maximal heart rate (moderate intensity, 15 min), or a seated control condition. Neuroplasticity within the primary motor cortex was then examined using a continuous theta burst stimulation (cTBS) paradigm. We found that exercise did not alter cortical excitability. Following cTBS, there was a transient inhibition of first dorsal interosseus motor-evoked potentials during control and low-intensity conditions, but this was only significantly different following the low-intensity state. Moderate-intensity exercise alone increased serum cortisol levels, but brain-derived neurotrophic factor levels did not increase across any condition. In summary, low-intensity cycling promoted the neuroplastic response to cTBS within the motor cortex of healthy adults. These findings suggest that light exercise has the potential to enhance the effectiveness of motor learning or recovery following brain damage.

  8. Process Improvements: Aerobic Food Waste Composting at ISF Academy

    Science.gov (United States)

    Lau, Y. K.

    2015-12-01

    ISF Academy, a school with 1500 students in Hong Kong, installed an aerobic food waste composting system in November of 2013. The system has been operational for over seven months; we will be making improvements to the system to ensure the continued operational viability and quality of the compost. As a school we are committed to reducing our carbon footprint and the amount of waste we send to the local landfill. Over an academic year we produce approximately 27 metric tons of food waste. Our system processes the food waste to compost in 14 days and the compost is used by our primary school students in a organic farming project.There are two areas of improvement: a) if the composting system becomes anaerobic, there is an odor problem that is noticed by the school community; we will be testing the use of a bio-filter to eliminate the odor problem and, b) we will be working with an equipment vendor from Australia to install an improved grease trap system. The grease and oil that is collected will be sold to a local company here in Hong Kong that processes used cooking oil for making biofuels. This system will include a two stage filtration system and a heated vessel for separating the oil from the waste water.The third project will be to evaluate biodegradable cutlery for the compositing in the system. Currently, we use a significant quantity of non-biodegradable cutlery that is then thrown away after one use. Several local HK companies are selling biodegradable cutlery, but we need to evaluate the different products to determine which ones will work with our composting system. The food waste composting project at ISF Academy demonstrates the commitment of the school community to a greener environment for HK, the above listed projects will improve the operation of the system.

  9. Comparison of dry medium culture plates for mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet products.

    Science.gov (United States)

    Park, Junghyun; Kim, Myunghee

    2013-12-01

    This study was performed to compare the performance of Sanita-Kun dry medium culture plate with those of traditional culture medium and Petrifilm dry medium culture plate for the enumeration of the mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet. Mesophilic aerobic bacteria were comparatively evaluated in milk, ice cream, ham, and codfish fillet using Sanita-Kun aerobic count (SAC), Petrifilm aerobic count (PAC), and traditional plate count agar (PCA) media. According to the results, all methods showed high correlations of 0.989~1.000 and no significant differences were observed for enumerating the mesophilic aerobic bacteria in the tested food products. SAC method was easier to perform and count colonies efficiently as compared to the PCA and PAC methods. Therefore, we concluded that the SAC method offers an acceptable alternative to the PCA and PAC methods for counting the mesophilic aerobic bacteria in milk, ice cream, ham, and codfish fillet products.

  10. Does aerobic exercise increase 24-hour ambulatory blood pressure among workers with high occupational physical activity? - A RCT

    DEFF Research Database (Denmark)

    Korshøj, Mette; Krause, Niklas; Clays, Els

    2017-01-01

    .9–3.8). Cleaners with high aerobic workload exhibited particularly high 24-hour ABP increases: systolic 6.0 mm Hg (95% CI 2.4–9.6), and diastolic 3.8 mm Hg (95% CI 1.3–6.4). CONCLUSION Aerobic exercise increased 24-hour ABP among cleaners. This adverse effect raises questions about the safety and intended benefits......OBJECTIVE High occupational physical activity (OPA) increases cardiovascular risk and aerobic exercise has been recommended for reducing this risk. This paper investigates the effects of an aerobic exercise intervention on 24-hour ambulatory blood pressure (ABP) among cleaners with high OPA....... METHODS Hundred and sixteen cleaners between 18 and 65 years were randomized. During the 4-month intervention period, the aerobic exercise group (AE) (n = 57) performed worksite aerobic exercise (2 × 30 minutes/week), while the reference group (REF) (n = 59) attended lectures. Between-group differences...

  11. Aerobic capacity and disease activity in children, adolescents and young adults with juvenile idiopathic arthritis (JIA

    Directory of Open Access Journals (Sweden)

    van Pelt Philomine A

    2012-08-01

    Full Text Available Abstract Background As patients with juvenile idiopathic arthritis (JIA progress into adulthood, long-term outcome is determined by disease activity, physical and psychosocial development. Decreased aerobic capacity may play a critical role in health-related outcomes in JIA, since it has been linked with cardiovascular morbidity and mortality in late adulthood. The objectives of the current study are to examine the aerobic capacity and its relation to parameters of disease activity in children, adolescents and young adults with JIA. Methods Sixty-three patients with JIA (aged 10–27 years were cross sectional studied regarding their aerobic capacity and correlations were made to demographic, disease-related variables, and medication utilization. in a cross-sectional study group of 63 patients of all subtypes. Patients were divided in three age groups, 10–13 years; 14–17 years and 18–27 years. Results Reduced aerobic capacity is found in clinical remission as well as active disease in all subtypes and all age groups. Aerobic capacity is more impaired in active disease shown by DAS 28, JADAS 27, ESR and serum thrombocyte counts. Lower haemoglobin has a negative impact. Long-term used medication including methotrexate and corticosteroids didn’t influence outcome. There is no association with current sports participation. Conclusion Reduced aerobic capacity is present in adolescents and young adults with JIA, both in active disease and in patients with remission. Measures of aerobic capacity may serve as important outcome measure in JIA.

  12. Dynamics Associated with Prolonged Ensiling and Aerobic Deterioration of Total Mixed Ration Silage Containing Whole Crop Corn

    OpenAIRE

    Wang, Huili; Ning, Tingting; Hao, Wei; Zheng, Mingli; Xu, Chuncheng

    2016-01-01

    This study investigated the dynamics associated with prolonged ensiling and aerobic deterioration of whole crop corn (WCC) silages and total mixed ration (TMR) silages containing WCC (C-TMR silages) to clarify the differences that account for the enhanced aerobic stability of TMR silages. Laboratory-scale barrel silos were randomly opened after 7, 14, 28, and 56 d of ensiling and were subjected to analyses of fermentation quality, microbial and temperature dynamics during aerobic exposure. WC...

  13. The Acute Effects of a Single Bout of Moderate-intensity Aerobic Exercise on Cognitive Functions in Healthy Adult Males

    OpenAIRE

    Nanda, Bijli; Balde, Jagruti; Manjunatha, S.

    2013-01-01

    Introduction: Single acute bouts of moderately-intense aerobic exercise like walking have been found to improve cognitive control of attention in children, but some studies have reported no improvement in cognitive flexibility following acute aerobic exercise. Submaximal aerobic exercise performed for 60 minutes facilitated specific aspects of information processing in adults but extended exercises leading to dehydration compromised both information processing and memory functions. Improvemen...

  14. Aerobic interval exercise with an eccentric contraction induces muscular hypertrophy and augmentation of muscular strength in rats

    OpenAIRE

    Tsumiyama, Wakako; Oki, Sadaaki; Takamiya, Naomi; Umei, Namiko; Shimizu, Michele Eisemann; Ono, Takeya; Otsuka, Akira

    2015-01-01

    [Purpose] The purpose of this study was to examine whether an aerobic interval exercise using an eccentric contraction would result in skeletal muscular hypertrophy and augmentation of muscular strength in rats. [Subjects and Methods] Twenty-one female Wistar rats were used in this study. The rats were randomly divided into three groups. The control group performed no exercise. The aerobic endurance exercise group ran for 90 min. The aerobic interval exercise group ran for a total of 90 minut...

  15. Two-stage anaerobic and post-aerobic mesophilic digestion of sewage sludge: Analysis of process performance and hygienization potential.

    Science.gov (United States)

    Tomei, M Concetta; Mosca Angelucci, Domenica; Levantesi, Caterina

    2016-03-01

    Sequential anaerobic-aerobic digestion has been demonstrated to be effective for enhanced sludge stabilization, in terms of increased solid reduction and improvement of sludge dewaterability. In this study, we propose a modified version of the sequential anaerobic-aerobic digestion process by operating the aerobic step under mesophilic conditions (T=37 °C), in order to improve the aerobic degradation kinetics of soluble and particulate chemical oxygen demand (COD). Process performance has been assessed in terms of "classical parameters" such as volatile solids (VS) removal, biogas production, COD removal, nitrogen species, and polysaccharide and protein fate. The aerobic step was operated under intermittent aeration to achieve nitrogen removal. Aerobic mesophilic conditions consistently increased VS removal, providing 32% additional removal vs. 20% at 20 °C. Similar results were obtained for nitrogen removal, increasing from 64% up to 99% at the higher temperature. Improved sludge dewaterability was also observed with a capillary suction time decrease of ~50% during the mesophilic aerobic step. This finding may be attributable to the decreased protein content in the aerobic digested sludge. The post-aerobic digestion exerted a positive effect on the reduction of microbial indicators while no consistent improvement of hygienization related to the increased temperature was observed. The techno-economic analysis of the proposed digestion layout showed a net cost saving for sludge disposal estimated in the range of 28-35% in comparison to the single-phase anaerobic digestion.

  16. Changes of the sweet taste sensitivity due to aerobic physical exercise

    Directory of Open Access Journals (Sweden)

    Ni Luh Putu Ayu Wardhani

    2011-03-01

    Full Text Available Background: Sweet taste is a pleasant sensation. Sweet taste is mostly consumed and fancied by many people. Physiologically, glucose is body's source of energy, but if over used it can be affected to the body's metabolism. This can be worsen if the person's not doing a healthy lifestyle. One way to implement a healthy lifestyle is by doing physical exercises. Purpose: The aim of this study was to determine changes in sensory sensitivity of sweet taste due to aerobic physical exercise. Methods: This study was conducted on subjects aged 20 to 30 years. The subjects did aerobic exercise using 80% load of MHR. The measurement sensitivity of the senses of the sweet taste was done for three times before the subject take aerobic physical exercise, four weeks after doing aerobic physical exercise, and eight weeks after doing aerobic physical exercise. Results: There was significant difference towards sensitivity of sweet taste sense before doing aerobic physical exercise, 4 week after doing the aerobic physical exercise, and 8 week after doing aerobic physical exercise. Conclusion: Aerobic physical exercise during eight weeks increase sweet taste sensitivity.Latar belakang: Rasa manis memberikan sensasi yang menyenangkan. Rasa manis merupakan jenis rasa yang paling banyak dikonsumsi dan disukai oleh sekelompok orang. Secara fisiologis, glukosa bisa berperan sebagai sumber energi, namun apabila dikonsumsi secara berlebihan dapat menimbulkan efek patologis. Hal ini dihubungkan dengan individu yang mempunyai gaya hidup yang tidak sehat. Salah satu cara yang bisa dilakukan untuk membiasakan gaya hidup sehat adalah dengan latihan fisik (olah raga. Tujuan: Penelitian ini bertujuan untuk membuktikan adanya perubahan sensitivitas indera kecap rasa manis setelah melakukan latihan fisik aerobik. Metode: Penelitian ini melibatkan subyek laki-laki, berusia 20–30 tahun. Subjek melakukan latihan fisik aerobik dengan intensitas sebesar 80% maximal heart rate

  17. Time of day has no effect on maximal aerobic and peak power

    Directory of Open Access Journals (Sweden)

    Sesboüé B

    2011-08-01

    Full Text Available N Bessot1,3, S Moussay1,2, B Dufour1,2, D Davenne1,2, B Sesboüé1,3, A Gauthier1,21Inserm, ERI27, Caen, France; 2University Caen, Caen, France; 3CHRU Caen, Explorations Fonctionnelles, Caen, FranceBackground: The aim of this study was to explore the effect of time of day on peak power reached during an exercise test and maximal aerobic power achieved when the subject reached maximal oxygen uptake.Methods: Fifteen male competitive endurance cyclists performed a standardized maximal incremental exercise test at 06:00 hours and 18:00 hours. The test began with a 5-minute warmup period at a workload of 150 W. The work rate was then increased by incremental steps of 30 W per minute until the respiratory exchange ratio reached 1.00. Thereafter, workload was increased in steps of 15 W per minute until exhaustion was reached.Results: No significant diurnal variation was detected in physiological parameters (maximal oxygen uptake and maximal heart rate or biomechanical parameters (maximal aerobic power, peak power.Conclusion: Circadian variations classically reported in competitive aerobic performances could be due to fluctuations in maximal aerobic endurance and/or improvement in gestural efficiency (pattern of muscle activity, effective force production, and kinematics.Keywords: chronobiology, maximal aerobic power, peak power, maximal oxygen uptake, maximal incremental test

  18. Biotransformation of nonylphenol ethoxylates during sewage treatment under anaerobic and aerobic conditions

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Biotransformation of nonylphenol ethoxylates (NPEOs) during continuous anaerobic sewage treatment was compared with the aerobic treatment of sewage spiked with 23 μmol/L technical NPEOs over a period of 90 d. Immediate degradation of NPEOs was observed under both anaerobic and aerobic conditions, indicating that the enzymes and bacteria required for NPEO degradation existed abundantly in both aerobic and anaerobic sludge. Both treatments achieved high removal (>92%) of the spiked NPEO9 mixture.Liquid chromatography-mass spectrometry (LC-MS) analysis showed that short-chain NPEOs (NPEO1-NPEO3) accumulated in anaerobic (2.01-2.56 μmol/L) and aerobic (1.62-2.03 μmol/L) effluents, with nonylphenol (NP) (0.24-0.31 μmol/L) as another group of metabolites in the anaerobic effluent, and nonylphenoxy carboxylates (NPECs) (2.79-3.30 μmol/L) in the aerobic effluent. Significant accumulation of NP in the anaerobic sludge and NPEO1-3 in the sludge of two reactors was observed. These results indicated that it was difficult to control these harmful metabolites in the conventional treatment processes. Denaturing gradient gel electrophoresis profiles of sludge samples support the speculation that the NPEO degradation bacteria might be the dominant indigenous species.

  19. Isolation and characterization of medically important aerobic actinomycetes in soil of iran (2006 - 2007).

    Science.gov (United States)

    Aghamirian, Mohammad Reza; Ghiasian, Seyed Amir

    2009-01-01

    The aerobic actinomycetes are a large group of soil-inhabiting bacteria that occur worldwide. Some of them are the main cause of two important diseases, nocardiosis and actinomycetoma. To identify the prevalence and geographic distribution of aerobic actinomycetes in soil of Qazvin province, a study was carried out during 2006-2007. In this study, the incidence and diversity of medically important aerobic actinomycetes was determined in 300 soil samples of different parts of Qazvin. The suspensions of superficial soil samples were prepared by adding of normal saline, streptomycin and chloramphenicol and the supernatants were cultured on brain-heart infusion agar and Sabouraud's dextrose agar contain cycloheximide. The isolated microorganisms were examined by Gram and acid-fast stains and were identified biochemically and morphologically. Of 96 aerobic actinomycetes isolates identified, Actinomadura madurae and Streptomyces somaliensis were the most frequently isolated species each representing 19.8% of isolates, followed by Nocardia asteroides (15.6%), N. otitidiscaviarum (9.4%), N. brasiliensis (7.3%), A. peletieri, S. griseus, and Nocardia spp. (each 5.2%), and N. transvalensis, Nocardiopsis dassonvillei, Actinomadura spp. and Streptomyces spp. (each 3.1%). To the best of our knowledge, this is the first report on epidemiological investigation of medically important aerobic actinomycetes in soil samples from Iran. In recent years, mycetoma and nocardiosis have been increasingly reported in Iran. The results showed that medically important actinomycetes occur in the environment of Iran and soil could be potential source of actinomycotic infections.

  20. Higher circulating leukocytes in women with PCOS is reversed by aerobic exercise.

    Science.gov (United States)

    Covington, Jeffrey D; Tam, Charmaine S; Pasarica, Magdalena; Redman, Leanne M

    2016-05-01

    Polycystic ovary syndrome (PCOS) is characterized by insulin resistance, elevated circulating leukocytes, and hypothesized to have higher adipose tissue inflammation. Aerobic exercise reduces circulating leukocytes and improves insulin sensitivity in obese individuals, but the effect of exercise on inflammation in PCOS is not known. We investigated circulating leukocytes, insulin sensitivity by euglycemic-hyperinsulinemic clamp, serum pro- and anti-inflammatory markers (hsCRP, TNF-α, total and high molecular weight adiponectin), and abdominal subcutaneous adipose tissue (SAT) gene expression of proinflammatory markers in 8 PCOS women and 8 obese control females matched for BMI. Additionally, in a prospective study, the 8 women with PCOS underwent a 16-week aerobic exercise regimen with the same measures performed post-intervention. Compared to controls, white blood cell counts (WBC) were 30% higher (p = 0.04) and circulating total adiponectin levels were 150% lower (p = 0.03) in women with PCOS at baseline/pre-exercise conditions. SAT gene expression of macrophage migration inhibitory factor (MIF, p aerobic exercise, insulin sensitivity improved (p exercise-induced change in WBC and circulating neutrophils correlated inversely with changes in glucose disposal rate (r = -0.73, p = 0.03; and r = -0.82, p = 0.01, respectively). Aerobic exercise reduced serum leptin (p aerobic exercise and is associated with improvements in insulin sensitivity.

  1. Effect of Aerobic Exercise Training on Blood Pressure in Indians: Systematic Review

    Directory of Open Access Journals (Sweden)

    Sonu Punia

    2016-01-01

    Full Text Available Introduction. High blood pressure (BP is one of the most important modifiable risk factors for cardiovascular diseases, which accounts for one in every eight deaths worldwide. It has been predicted that, by 2020, there would be 111% increase in cardiovascular deaths in India. Aerobic exercise in the form of brisk walking, jogging, running, and cycling would result in reduction in BP. Many meta-analytical studies from western world confirm this. However, there is no such review from Indian subcontinent. Objective. Our objective is to systematically review and report the articles from India in aerobic exercise on blood pressure. Methodology. Study was done in March 2016 in Google Scholar using search terms “Aerobic exercise” AND “Training” AND “Blood pressure” AND “India.” This search produced 3210 titles. Results. 24 articles were identified for this review based on inclusion and exclusion criteria. Total of 1107 subjects participated with median of 25 subjects. Studies vary in duration from +3 weeks to 12 months with each session lasting 15–60 minutes and frequency varies from 3 to 8 times/week. The results suggest that there was mean reduction of −05.00 mmHg in SBP and −03.09 mmHg in DBP after aerobic training. Conclusion. Aerobic training reduces the blood pressure in Indians.

  2. Influence of Aerobic Training and Combinations of Interventions on Cognition and Neuroplasticity after Stroke.

    Science.gov (United States)

    Constans, Annabelle; Pin-Barre, Caroline; Temprado, Jean-Jacques; Decherchi, Patrick; Laurin, Jérôme

    2016-01-01

    Stroke often aggravated age-related cognitive impairments that strongly affect several aspects of quality of life. However, few studies are, to date, focused on rehabilitation strategies that could improve cognition. Among possible interventions, aerobic training is well known to enhance cardiovascular and motor functions but may also induce beneficial effects on cognitive functions. To assess the effectiveness of aerobic training on cognition, it seems necessary to know whether training promotes the neuroplasticity in brain areas involved in cognitive functions. In the present review, we first explore in both human and animal how aerobic training could improve cognition after stroke by highlighting the neuroplasticity mechanisms. Then, we address the potential effect of combinations between aerobic training with other interventions, including resistance exercises and pharmacological treatments. In addition, we postulate that classic recommendations for aerobic training need to be reconsidered to target both cognition and motor recovery because the current guidelines are only focused on cardiovascular and motor recovery. Finally, methodological limitations of training programs and cognitive function assessment are also developed in this review to clarify their effectiveness in stroke patients.

  3. Combination of ozonation with conventional aerobic oxidation for distillery wastewater treatment.

    Science.gov (United States)

    Sangave, Preeti C; Gogate, Parag R; Pandit, Aniruddha B

    2007-05-01

    Laboratory-scale experiments were conducted in order to investigate the effect of ozone as pre-aerobic treatment and post-aerobic treatment for the treatment of the distillery wastewater. The degradation of the pollutants present in distillery spent wash was carried out by ozonation, aerobic biological degradation processes alone and by using the combinations of these two processes to investigate the synergism between the two modes of wastewater treatment and with the aim of reducing the overall treatment costs. Pollutant removal efficiency was followed by means of global parameters directly related to the concentration of organic compounds in those effluents: chemical oxygen demand (COD) and the color removal efficiency in terms of absorbance of the sample at 254 nm. Ozone was found to be effective in bringing down the COD (up to 27%) during the pretreatment step itself. In the combined process, pretreatment of the effluent led to enhanced rates of subsequent biological oxidation step, almost 2.5 times increase in the initial oxidation rate has been observed. Post-aerobic treatment with ozone led to further removal of COD along with the complete discoloration of the effluent. The integrated process (ozone-aerobic oxidation-ozone) achieved approximately 79% COD reduction along with discoloration of the effluent sample as compared to 34.9% COD reduction for non-ozonated sample, over a similar treatment period.

  4. Bacterial community composition and abundance in leachate of semi-aerobic and anaerobic landfills

    Institute of Scientific and Technical Information of China (English)

    Wei Zhang; Bo Yue; Qi Wang; Zechun Huang; Qifei Huang; Zengqiang Zhang

    2011-01-01

    The abundance and phylogenetic composition of bacterial community in leachate of semi-aerobic and anaerobic landfill were compared through real-time polymerase chain reaction and denaturing gradient gel electrophoresis.In semi-aerobic landfill scenario,the bacterial 16S rRNA copy numbers in leachate had no significant reduction from initial stage to stable period.In the scenario of anaerobic landfill,the largest bacterial 16S rRNA gene copy number was found in leachate at initial stage,but it reduced significantly at stable period.Moreover,methane-oxidizing bacteria population in stable period was lower than that in initial period in both two landfill processes.However,semi-aerobic landfill leachate had more methanotrophic bacteria populations than that in the anaerobic one.Furthermore,according to the sequences and phylogenetic analysis,obvious difference could be detected in bacterial community composition in different scenarios.Proteobacteria and bacteroidetes took up a dominantly higher proportion in semi-aerobic landfill leachate.To summarize up,different landfill methods and its landfill ages had crucial impacts on bacterial abundance and composition in leachate of semi-aerobic and anaerobic landfills.

  5. Effects of extracellular polymer substances on aerobic granulation in sequencing batch reactors

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-ping; LIU Li-li; YAO Jie; SUN Li-xin; CAI Wei-min

    2009-01-01

    The effects of extracellular polymeric substances (EPS) on aerobic granulation in sequencing batch reactors (SBR) were investigated by evaluating the EPS content, and the relationship between EPS composition and surface properties of glucose-fed aerobic granules. The results show that aerobic granular sludge contains more EPS than seed sludge, and it is about 47 mg/gMLSS. Corresponding to the changes of EPS, the surface charge of microorganisms in granules increases from -0. 732 to -0. 845 meq/gMLSS, whereas the hydrophobicry changes significantly from 48.46% to 73. 16%. It is obviously that changes of EPS in sludge alter the negative surface charge and hydrophobieity of microorganisms in granules, enhance the polymeric interaction and promote the aerobic granulation. Moreover, EPS can serve as carbon and energy reserves in granulation, thus the growth between the interior and exterior bacteria is balanced, and the integrality of granules is maintained.SEM observation of the granules exhibits that EPS in granules are ropy ; by mixing with bacteria, compact matrix structure can be formed. The distribution of EPS in granules profiles the importance of EPS storage. It can be concluded that EPS play a crucial role in aerobic granulation.

  6. Biodegradation of p-cresol by aerobic granules in sequencing batch reactor

    Institute of Scientific and Technical Information of China (English)

    Farrukh Basheer; I.H.Farooqi

    2012-01-01

    The cultivation of aerobic granules in sequencing batch reactor for the biodegradation of p-cresol was studied.The reactor was started with 100 mg/L of p-cresol.Aerobic granules first appeared within one month of start up.The granules were large and strong and had a compact structure.The diameter of stable granules was in the range of 1-5 mm.The integrity coefficient and granules density was found to be 96% and 1046 kg/m3,respectively.The settling velocity of granules was found to be in the range of 2×10-2-6×10-2 m/sec.The aerobic granules were able to degrade p-cresol upto 800 mg/L at a removal efficiency of 88%.Specific p-cresol degradation rate in aerobic granules followed Haldane model for substrate inhibition.High specific p-cresol degradation rate up to 0.96 g pcresol/(g VSS.day) were sustained upto p-cresol concentration of 400 mg/L.Higher removal efficiency,good settling characteristics of aerobic granules,makes sequencing batch reactor suitable for enhancing the microorganism potential for biodegradation of inhibitory compounds.

  7. Nonmicrobial aerobic methane emission from poplar shoot cultures under low-light conditions.

    Science.gov (United States)

    Brüggemann, Nicolas; Meier, Rudolf; Steigner, Dominik; Zimmer, Ina; Louis, Sandrine; Schnitzler, Jörg-Peter

    2009-06-01

    The aerobic formation of methane in plants has been reported previously, but has been questioned by a number of researchers. Recently, isotopic evidence demonstrated that ultraviolet irradiation and heating lead to photochemical or thermal aerobic methane formation mainly from plant pectin in the absence of microbial methane production. However, the origin of aerobic methane formation from plant material observed under low temperature and low-light/dark conditions is still unclear. Here we show that Grey poplar (Populus × canescens, syn. Populus tremula × Populus alba) plants derived from cell cultures under sterile conditions released 13C-labeled methane under low-light conditions after feeding the plants with 13CO2. Molecular biological analysis proved the absence of any microbial contamination with known methanogenic microorganisms and ruled out the possibility that methane emission from our poplar shoot cultures under aerobic low-light/dark and ambient temperature conditions could be of microbial origin. The CH4 release rates in our experiment were in the range of 0.16-0.7 ng g-1 DW h-1, adding evidence to the growing opinion that the quantitative role of aerobic methane emissions from plants in the global methane budget, at least from cold temperate or boreal regions, is only of minor importance.

  8. Investigating the nitrification and denitrification kinetics under aerobic and anaerobic conditions by Paracoccus denitrificans ISTOD1.

    Science.gov (United States)

    Medhi, Kristina; Singhal, Anjali; Chauhan, D K; Thakur, Indu Shekhar

    2017-03-16

    Municipal wastewater contains multiple nitrogen contaminants such as ammonia, nitrate and nitrite. Two heterotrophic nitrifier and aerobic denitrifiers, bacterial isolates ISTOD1 and ISTVD1 were isolated from domestic wastewater. On the basis of removal efficiency of ammonia, nitrate and nitrite under both aerobic and anaerobic conditions, ISTOD1 was selected and identified as Paracoccus denitrificans. Aerobically, NH4(+)-N had maximum specific nitrogen removal rate (Rxi) of 7.6g/gDCW/h and anaerobically, NO3(-)N showed Rxi of 2.5*10(-1)g/g DCW/h. Monod equation described the bioprocess kinetic coefficients, µmax and Ks, obtained by regression. Error functions were calculated to validate the Monod equation experimental data. Aerobic NO3(-)N showed the highest YW of 0.372mg DCW/mg NO3(-)N among the five conditions. ISTOD1 serves as a potential candidate for treating nitrogen rich wastewater using simultaneous nitrification and aerobic denitrification. It can be used in bioaugmentation studies under varied condition.

  9. Postural Balance Following Aerobic Fatigue Tests: A Longitudinal Study Among Young Athletes.

    Science.gov (United States)

    Steinberg, Nili; Eliakim, Alon; Zaav, Aviva; Pantanowitz, Michal; Halumi, Monder; Eisenstein, Tamir; Meckel, Yoav; Nemet, Dan

    2016-01-01

    General fatigue can cause aggravation of postural balance, with increased risk for injuries. The present longitudinal study aimed to evaluate the postural balance of young athletes following field aerobic tests throughout 1 year of training. Thirty children from a sports center in Nazareth, participating in a 3 times/week training program (specific to basketball, soccer, or athletic training), were assessed. Postural balance parameters were taken before, immediately after, and 10 min after a 20 m shuttle-run aerobic test, at 3 time points during 1 training year (Start/Y, Mid/Y, and End/Y). Fitness improved at the Mid/Y and End/Y compared to Start/Y. Postural balance significantly deteriorated immediately after the aerobic test and improved significantly in the 10-min testing in all 3 time points, with significant deterioration in the End/Y compared with the Start/Y. In conclusions, postural balance deteriorates immediately after aerobic exercises, and at the end of the year. To better practice drills related to postural balance and possibly to prevent injuries, it is best for young athletes to properly rest immediately following aerobic exercises and to practice postural balance mainly at the beginning and at the middle of the training year.

  10. Simultaneous anaerobic-aerobic biodegradation of halogenated phenolic compound under oxygen-limited conditions

    Institute of Scientific and Technical Information of China (English)

    CHEN Yuan-cai; LAN Hui-xia; ZHAN Huai-yu; FU Shi-yu

    2005-01-01

    The successful application of co-immobilized aerobic-anaerobic biomaes under limited aeration in wastewater treatment systems would eliminate the problems associated with the intermediates mono-chlorophenol(MCP) and di-chlorophenol(DCP) accumulations. With low initial pentachlorophenol(PCP) concentration, all PCP could be completely removed under oxygen-limited strict anaerobic conditions,and the removal efficiencies with different initial haedspace oxygen percentage(IHOP) were not obviously different from each other. While at high initial PCP concentration, under strictly anaerobic conditions PCP and their intermediates were clearly higher than that under other conditions, and produced obvious accumulation, the highest PCP reduction was achieved by the system receiving 30 IHOP, oxygen-limited system also exhibited lower residual TOC concentration and lower concentration of metabolic intermediates MCP and DCP. These results suggested that under strictly anaerobic condition the reductive dechlorination of low chlorinated compounde became rate limiting in the reductive dechlorination pathway, less chlorinated compounds be more amenable to aerobic degradation, and the aerobes of outer layers could function under limited oxygen. The co-immobilized aerobic-anaerobic biomass for methanogeneeis under limited-aeration for chlorophenol degradation might be an attractive and efficient altemative for the sequential anaerobic/aerobic system to achieve mineralization of a broad range of recalcitrance highly chlorinated organics and low final TOC concentrations.

  11. Beneifcial mechanisms of aerobic exercise on hepatic lipid metabolism in non-alcoholic fatty liver disease

    Institute of Scientific and Technical Information of China (English)

    Rui Guo; Emily C Liong; Kwok Fai So; Man-Lung Fung; George L Tipoe

    2015-01-01

    BACKGROUND:Non-alcoholic fatty liver disease (NAFLD) refers to any fatty liver disease that is not due to excessive use of alcohol. NAFLD probably results from abnormal hepatic lipid metabolism and insulin resistance. Aerobic exercise is shown to improve NAFLD. This review aimed to evaluate the molecular mechanisms involved in the beneifcial effects of aerobic exercise on NAFLD. DATA SOURCE:We searched articles in English on the role of aerobic exercise in NAFLD therapy in PubMed. RESULTS:The mechanisms of chronic aerobic exercise in regulating the outcome of NAFLD include: (i) reducing in-trahepatic fat content by down-regulating sterol regulatory element-binding protein-1c and up-regulating peroxisome proliferator-activated receptorγ expression levels; (ii) decreas-ing hepatic oxidative stress through modulating the reactive oxygen species, and enhancing antioxidant enzymes such as catalase and glutathione peroxidase; (iii) ameliorating hepatic inlfammation via the inhibition of pro-inlfammatory media-tors such as tumor necrosis factor-alpha and interleukin-1 beta; (iv) attenuating mitochondrial dependent apoptosis by reducing cytochrome C released from the mitochondria to the cytosol; and (v) inducing hepato-protective autophagy. CONCLUSION:Aerobic exercise, via different mechanisms, signiifcantly decreases the fat content of the liver and improves the outcomes of patients with NAFLD.

  12. The Effect of 8 weeks aerobic exercise and yoga on primary dismenorrhea

    Directory of Open Access Journals (Sweden)

    T Siahpour

    2013-10-01

    Full Text Available Abstract Background & aim: Dysmenorrhea, menstrual cramps without physical pain is a common complaint in gynecology. The aim of this study was to investigate the effect of aerobic training on primary Dysmenorrhea in a period of 8 weeks. Materials & Methods: In the present clinical-trial study, 60 non-athlete girls with primary Dysmenorrhea were randomly divided into three groups: aerobic training, yoga and control groups. Based on the visual analog scale of pain intensity, pain duration and amount of analgesics administered was assessed before and after the period of primary Dysmenorrhea using a questionnaire. In this eight-week exercise program, the aerobic exercises group for 60 minutes in three weeks and yoga exercises group in three sessions per week for 60 minutes, the yoga breathing techniques, exercises, asana and relaxation techniques were performed. There was no intervention in the control group. Data were analyzed by Wilcoxon, Kruskal-Wallis and Mann Whitney (p0.05. There was a significant decrease in the analgesic consumption in the yoga group compared to the exercise group (p<0/05. Conclusion: Both aerobic and yoga are effective in the treatment of primary Dysmenorrhea, but yoga has a greater reduction property on drug dosage. Key words: primary dysmenorrhea, aerobic exercise, yoga exercise, female student

  13. Removal of Organic Micropollutants by Aerobic Activated Sludge

    KAUST Repository

    Wang, Nan

    2013-06-01

    The study examined the removal mechanism of non-acclimated and acclimated aerobic activated sludge for 29 target organic micropollutants (OMPs) at low concentration. The selection of the target OMPs represents a wide range of physical-chemical properties such as hydrophobicity, charge state as well as a diverse range of classes, including pharmaceuticals, personal care products and household chemicals. The removal mechanisms of OMPs include adsorption, biodegradation, hydrolysis, and vaporization. Adsorption and biodegradation were found to be the main routes for OMPs removal for all target OMPs. Target OMPs responded to the two dominant removal routes in different ways: (1) complete adsorption, (2) strong biodegradation and weak adsorption, (3) medium biodegradation and adsorption, and (4) weak sorption and weak biodegradatio. Kinetic study showed that adsorption of atenolol, mathylparaben and propylparaben well followed first-order model (R2: 0.939 to 0.999) with the rate constants ranging from 0.519-7.092 h-1. For biodegradation kinetics, it was found that benzafibrate, bisphenol A, diclofenac, gemfibrozil, ibuprofen, caffeine and DEET followed zero-order model (K0:1.15E-4 to 0.0142 μg/Lh-1, R2: 0.991 to 0.999), while TCEP, naproxen, dipehydramine, oxybenzone and sulfamethoxazole followed first-order model (K1:1.96E-4 to 0.101 h-1, R2: 0.912 to 0.996). 4 Inhibition by sodium azide (NaN3)and high temperature sterilization was compared, and it was found that high temperature sterilization will damage cells and change the sludge charge state. For the OMPs adaptation removal study, it was found that some of OMPs effluent concentration decreased, which may be due to the slow adaptation of the sludge or the increase of certain bacteria culture; some increased due to chromic toxicity of the chemicals; most of the OMPs had stable effluent concentration trend, it was explained that some of the OMPs were too difficutl to remove while other showed strong quick adaptation

  14. Communal microaerophilic-aerobic biodegradation of Amaranth by novel NAR-2 bacterial consortium.

    Science.gov (United States)

    Chan, Giek Far; Rashid, Noor Aini Abdul; Chua, Lee Suan; Ab llah, Norzarini; Nasiri, Rozita; Ikubar, Mohamed Roslan Mohamad

    2012-02-01

    A novel bacterial consortium, NAR-2 which consists of Citrobacter freundii A1, Enterococcus casseliflavus C1 and Enterobacter cloacae L17 was investigated for biodegradation of Amaranth azo dye under sequential microaerophilic-aerobic condition. The NAR-2 bacterial consortium with E. casseliflavus C1 as the dominant strain enhanced the decolorization process resulting in reduction of Amaranth in 30 min. Further aerobic biodegradation, which was dominated by C. freundii A1 and E. cloacae L17, allowed biotransformation of azo reduction intermediates and mineralization via metabolic pathways including benzoyl-CoA, protocatechuate, salicylate, gentisate, catechol and cinnamic acid. The presence of autoxidation products which could be metabolized to 2-oxopentenoate was elucidated. The biodegradation mechanism of Amaranth by NAR-2 bacterial consortium was predicted to follow the steps of azo reduction, deamination, desulfonation and aromatic ring cleavage. This is for the first time the comprehensive microaerophilic-aerobic biotransformation pathways of Amaranth dye intermediates by bacterial consortium are being proposed.

  15. Effect of an aerobic training program as complementary therapy in patients with moderate depression.

    Science.gov (United States)

    de la Cerda, Pablo; Cervelló, Eduardo; Cocca, Armando; Viciana, Jesús

    2011-06-01

    The aim of this study was to assess the effects of an aerobic training program as complementary therapy in patients suffering from moderate depression. 82 female patients weredivided into a group that received traditional pharmacotherapy (Fluoxetine 20 mg) and a group that received pharmacotherapy plus an aerobic training program. This program was carried out for eight consecutive weeks, three days per week, and included gymnastics, dancing, and walking. Depressive symptoms were measured with the Beck Depression Inventory and the ICD-10 Guide for Depression Diagnosis, both administered before and after treatments. The results confirm the effectiveness of the aerobic training program as a complementary therapy to diminish depressive symptoms in patients suffering from moderate depression.

  16. Increased lactate threshold after five weeks of treadmill aerobic training in rats.

    Science.gov (United States)

    Brito Vieira, W H; Halsberghe, M J E; Schwantes, M L B; Perez, S E A; Baldissera, V; Prestes, J; Prestes, P; Farias, D L; Parizotto, N A

    2014-05-01

    The aim of the present study was to analyse the lactate threshold (LT) changes in rats submitted to an aerobic treadmill-training programme. Twenty-five Wistar rats were divided into two groups: a sedentary control group (CG), and a trained group (TG) submitted to an aerobic training during 5 weeks. All the animals were submitted to an incremental treadmill exercise test in order to determine LT. There was an increase in the maximum running speed in the TG (from 32.25 ± 1.27 to 47.75 ± 3.13 m.min-1 - p = 0.001), and running speed at LT (from 26.21 ± 1.15 to 35.30 ± 2.24 m.min-1 - p = 0.004), a part from the reduction in blood lactate at LT. LT can be determined in rats, and aerobic training induced positive oxidative physiological adaptations in the animals.

  17. Effect of aerobic exercise and raloxifene combination therapy on senile osteoporosis.

    Science.gov (United States)

    Zhao, Chengjin; Hou, Haibing; Chen, Yutao; Lv, Kai

    2016-06-01

    [Purpose] This study assessed the effects of combined application of raloxifene and aerobic exercise on senile osteoporosis. [Subjects and Methods] A total of 70 elderly patients with osteoporosis, who treated at our hospital between April 2013 and August 2014, were divided into equal-sized observation and control groups. The control group was administered raloxifene, whereas the observation group received raloxifene treatment plus aerobic exercise. [Results] Outpatient outcomes were considered dependent variables. After treatment, the two groups differed significantly in terms of lumbar spine (L2-L4) and proximal femoral bone mineral density. The urine pyridine/creatinine ratio decreased significantly and serum calcitonin level increased significantly in the observation group. These differences were statistically significant. [Conclusion] Raloxifene combined with aerobic exercise therapy significantly improves bone density and promotes bone formation in patients with senile osteoporosis.

  18. [Self-aggregation property of bacterial alginates extracted from aerobic granules].

    Science.gov (United States)

    Lin, Yue-Mei; Wang, Lin

    2008-05-01

    To explore bacterial alginates role in aerobic granules' formation, the alginate was extracted from aerobic granules and identified. Its aggregation property in 50 mg x L(-1) CaCl2 solution was investigated by the atomic force microscopy (AFM). Bacterial alginates amounted to 35.1% +/- 1.9% of granules' dry mass. With the concentration increased from 10 mg x L(-1) to 500 mg x L(-1) in 50 mg x L(-1) CaCl2, the extracted alginates tended to form ordered aggregations, with the shape changed from randomly distributed globules, to rod-like and flower-shaped aggregations, and finally to weblike networks due to their supramolecular self-assembly property. The three dimensional alginate-metal gel is the structural polymer of aerobic granules, and the alginates-Ca2+ gel formation plays an important role in granules' formation and structure stabilization.

  19. Factors affecting biological denitrifying dephosphatation in anaerobic/anoxic/aerobic sequencing batch reactor

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This study was conducted to verify and discuss the denitrifying dephosphatation under different levels of nitrate concentration and retention time of anoxic/aerobic process in a Sequencing Batch Reactor ( SBR ).The results of tests demonstrated that there were two kinds of phosphorus-accumulating organisms (PAOs) in the biological excess phosphorus removal (BEPR) system. One was non-DNPAOs that could only use oxygen as terminal electron acceptors, the other was denitrifying PAOs (DNPAOs) that could use both nitrate and oxygen as terminal electron acceptors. Phosphorus uptake efficiency could be attained under anoxic period ranging from 28.7%-96.7% in an anacrobic/anoxic/aerobic system. Experimental results showed that nitrate concentration and retention time of anoxic/aerobic process were the key factors affecting the course of denitrifying dephosphatation.

  20. Biodegradation of triclosan and formation of methyl-triclosan in activated sludge under aerobic conditions

    DEFF Research Database (Denmark)

    Chen, Xijuan; Nielsen, Jeppe Lund; Furgal, Karolina;

    2011-01-01

    Triclosan is an antimicrobial agent which is widely used in household and personal care products. Widespread use of this compound has led to the elevated concentrations of triclosan in wastewater, wastewater treatment plants (WWTPs) and receiving waters. Removal of triclosan and formation...... of triclosan- methyl was investigated in activated sludge from a standard activated sludge WWTP equipped with enhanced biological phosphorus removal. The removal was found to occur mainly under aerobic conditions while under anoxic (nitrate reducing) and anaerobic conditions rather low removal rates were...... determined. In a laboratory-scale activated sludge reactor 75% of the triclosan was removed under aerobic conditions within 150 h, while no removal was observed under anaerobic or anoxic conditions. One percent of the triclosan was converted to triclosan-methyl under aerobic conditions, less under anoxic...