120 research outputs found

    Mangrove trees affect the community structure and distribution of anammox bacteria at an anthropogenic-polluted mangrove in the Pearl River Delta reflected by 16S rRNA and hydrazine oxidoreductase (HZO) encoding gene analyses

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    Anaerobic ammonium oxidizing (anammox) bacterial community structures were investigated in surface (1–2 cm) and lower (20–21 cm) layers of mangrove sediments at sites located immediately to the mangrove trees (S0), 10 m (S1) and 1000 m (S2) away from mangrove trees in a polluted area of the Pearl River Delta. At S0, both 16S rRNA and hydrazine oxidoreductase (HZO) encoding genes of anammox bacteria showed high diversity in lower layer sediments, but they were not detectable in lower layer sediments in mangrove forest. S1 and S2 shared similar anammox bacteria communities in both surface and lower layers, which were quite different from that of S0. At all three locations, higher richness of anammox bacteria was detected in the surface layer than the lower layer; 16S rRNA genes revealed anammox bacteria were composed by four phylogenetic clusters affiliated with the “Scalindua” genus, and one group related to the potential anammox bacteria; while the hzo genes showed that in addition to sequences related to the “Scalindua”, sequences affiliated with genera of “Kuenenia”, “Brocadia”, and “Jettenia” were also detected in mangrove sediments. Furthermore, hzo gene abundances decreased from 36.5 × 104 to 11.0 × 104 copies/gram dry sediment in lower layer sediments while increased from below detection limit to 31.5 × 104 copies/gram dry sediment in lower layer sediments from S0 to S2. The results indicated that anammox bacteria communities might be strongly influenced by mangrove trees. In addition, the correlation analysis showed the redox potential and the molar ratio of ammonium to nitrite in sediments might be important factors affecting the diversity and distribution of anammox bacteria in mangrove sediments

    Spatial distribution and abundances of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in mangrove sediments

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    We investigated the diversity, spatial distribution, and abundances of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in sediment samples of different depths collected from a transect with different distances to mangrove forest in the territories of Hong Kong. Both the archaeal and bacterial amoA genes (encoding ammonia monooxygenase subunit A) from all samples supported distinct phylogenetic groups, indicating the presences of niche-specific AOA and AOB in mangrove sediments. The higher AOB abundances than AOA in mangrove sediments, especially in the vicinity of the mangrove trees, might indicate the more important role of AOB on nitrification. The spatial distribution showed that AOA had higher diversity and abundance in the surface layer sediments near the mangrove trees (0 and 10 m) but lower away from the mangrove trees (1,000 m), and communities of AOA could be clustered into surface and bottom sediment layer groups. In contrast, AOB showed a reverse distributed pattern, and its communities were grouped by the distances between sites and mangrove trees, indicating mangrove trees might have different influences on AOA and AOB community structures. Furthermore, the strong correlations among archaeal and bacterial amoA gene abundances and their ratio with NH4+, salinity, and pH of sediments indicated that these environmental factors have strong influences on AOA and AOB distributions in mangrove sediments. In addition, AOA diversity and abundances were significantly correlated with hzo gene abundances, which encodes the key enzyme for transformation of hydrazine into N2 in anaerobic ammonium-oxidizing (anammox) bacteria, indicating AOA and anammox bacteria may interact with each other or they are influenced by the same controlling factors, such as NH4+. The results provide a better understanding on using mangrove wetlands as biological treatment systems for removal of nutrients

    Phylogeography and Genetic Variation of Triatoma dimidiata, the Main Chagas Disease Vector in Central America, and Its Position within the Genus Triatoma

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    Chagas disease is a serious parasitic disease of Latin America. Human contamination in poor rural or periurban areas is mainly attributed to haematophagous triatomine insects. Triatoma includes important vector species, as T. dimidiata in Central and Meso-America. DNA sequences, phylogenetic methods and genetic variation analyses are combined in a large interpopulational approach to investigate T. dimidiata and its closest relatives within Triatoma. The phylogeography of Triatoma indicates two colonization lineages northward and southward of the Panama isthmus during ancient periods, with T. dimidiata presenting a large genetic variability related to evolutionary divergences from a Mexican-Guatemalan origin. One clade remained confined to Yucatan, Chiapas, Guatemala and Honduras, with extant descendants deserving species status: T. sp. aff. dimidiata. The second clade gave rise to four subspecies: T. d. dimidiata in Guatemala and Mexico (Chiapas) up to Honduras, Nicaragua, Providencia island, and introduced into Ecuador; T. d. capitata in Panama and Colombia; T. d. maculipennis in Mexico and Guatemala; and T. d. hegneri in Cozumel island. This taxa distinction may facilitate the understanding of the diversity of vectors formerly included under T. dimidiata, their different transmission capacities and the disease epidemiology. Triatoma dimidiata will offer more problems for control than T. infestans in Uruguay, Chile and Brazil, although populations in Ecuador are appropriate targets for insecticide-spraying

    A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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    Meeting abstrac

    Measurement of the WZ production cross section in pp collisions at root s=13 Tev

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    Relative Modification of Prompt psi(2S) and J/psi Yields from pp to PbPb Collisions at root(S)(NN)=5.02 TeV

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    Peer reviewe

    Plant Growth-Promoting Microbes from Herbal Vermicompost

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    Overreliance on chemical pesticides and fertilizers has resulted in problems including safety risks, outbreaks of secondary pests normally held in check by natural enemies, insecticide resistance, environmental contamination, and decrease in biodiversity. The increasing costs and negative effects of pesticides and fertilizers necessitate the idea of biological options of crop protection and production. This includes the use of animal manure, crop residues, microbial inoculum, and composts. They provide natural nutrition, reduce the use of inorganic fertilizers, develop biodiversity, increase soil biological activity, maintain soil physical properties, and improve environmental health

    National identity predicts public health support during a global pandemic

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    Understanding collective behaviour is an important aspect of managing the pandemic response. Here the authors show in a large global study that participants that reported identifying more strongly with their nation reported greater engagement in public health behaviours and support for public health policies in the context of the pandemic.Changing collective behaviour and supporting non-pharmaceutical interventions is an important component in mitigating virus transmission during a pandemic. In a large international collaboration (Study 1, N = 49,968 across 67 countries), we investigated self-reported factors associated with public health behaviours (e.g., spatial distancing and stricter hygiene) and endorsed public policy interventions (e.g., closing bars and restaurants) during the early stage of the COVID-19 pandemic (April-May 2020). Respondents who reported identifying more strongly with their nation consistently reported greater engagement in public health behaviours and support for public health policies. Results were similar for representative and non-representative national samples. Study 2 (N = 42 countries) conceptually replicated the central finding using aggregate indices of national identity (obtained using the World Values Survey) and a measure of actual behaviour change during the pandemic (obtained from Google mobility reports). Higher levels of national identification prior to the pandemic predicted lower mobility during the early stage of the pandemic (r = -0.40). We discuss the potential implications of links between national identity, leadership, and public health for managing COVID-19 and future pandemics

    Measurement of the CKM angle Îł\gamma using B0→DK∗0B^0 \rightarrow D K^{*0} with D→KS0π+π−D \rightarrow K^0_S \pi^+ \pi^- decays

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    A model-dependent amplitude analysis of the decay B0→D(KS0π+π−)K∗0B^0\rightarrow D(K^0_S\pi^+\pi^-) K^{*0} is performed using proton-proton collision data corresponding to an integrated luminosity of 3.0fb−1^{-1}, recorded at s=7\sqrt{s}=7 and 8TeV8 TeV by the LHCb experiment. The CP violation observables x±x_{\pm} and y±y_{\pm}, sensitive to the CKM angle Îł\gamma, are measured to be \begin{eqnarray*} x_- &=& -0.15 \pm 0.14 \pm 0.03 \pm 0.01, y_- &=& 0.25 \pm 0.15 \pm 0.06 \pm 0.01, x_+ &=& 0.05 \pm 0.24 \pm 0.04 \pm 0.01, y_+ &=& -0.65^{+0.24}_{-0.23} \pm 0.08 \pm 0.01, \end{eqnarray*} where the first uncertainties are statistical, the second systematic and the third arise from the uncertainty on the D→KS0π+π−D\rightarrow K^0_S \pi^+\pi^- amplitude model. These are the most precise measurements of these observables. They correspond to Îł=(80−22+21)∘\gamma=(80^{+21}_{-22})^{\circ} and rB0=0.39±0.13r_{B^0}=0.39\pm0.13, where rB0r_{B^0} is the magnitude of the ratio of the suppressed and favoured B0→DK+π−B^0\rightarrow D K^+ \pi^- decay amplitudes, in a KπK\pi mass region of ±50MeV\pm50 MeV around the K∗(892)0K^*(892)^0 mass and for an absolute value of the cosine of the K∗0K^{*0} decay angle larger than 0.40.4.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-007.htm
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