789 research outputs found
Isolation and Characterization of Bacillus sp BZ-001H Capable of Biodegrading Formaldehyde at High Concentration
No full textA formaldehyde-degrading bacterium named BZ-001H was isolated from activated sludge while searching for an efficient strain of bacteria for bioaugmentation during treatment of high-concentration formaldehyde wastewater. It was identified as Bacillus sp. by cell and colony morphologies, biochemical properties, and 16S rDNA sequence analysis. Further study showed that BZ-001H retained its activity with respect to formaldehyde degradation when the pH range was 5-10, temperature range was 5-45 degrees C, and initial formaldehyde concentration was 4,000-20,000mg/L. BZ-001H exhibited highest removal efficiency and growth rate at pH 7, temperature of 30 degrees C, and 8,000mg/L of formaldehyde. Moreover, formic acid and methanol were intermediate products. In addition, formaldehyde removal rate was slightly effected by initial substrate concentration, but it was decreased with impact of formaldehyde concentration and intermediate products in the early 9h. This bacterium might reveal potential with regard to biological formaldehyde treatment in real formaldehyde wastewater due to its strong tolerance to various physicochemical conditions. Overall, this article enriched the study of the biodegradation of high concentration of toxic and refractory organic substrate
Singular values of two-parameter families λ((bz−1)/z)μ and λ(z/(bz−1))η
No full textAbstractThe singular values of two kinds of two-parameter families of functions (i) fλ,μ(z)=λ((bz−1)/z)μ and fλ,μ(0)=λ(lnb)μ, μ>0, (ii) gλ,η(z)=λ(z/(bz−1))η and gλ,η(0)=λ/(lnb)η, η>0; λ∈ℝ∖{0}, z∈ℂ, b>0, b≠1 are described. It is shown that all the critical values of fλ,μ(z) and gλ,η(z) lie interior and exterior of the disk centered at origin and having radii |λ(lnb)μ| and |λ/(lnb)η| respectively. Further, it is proved that both the functions fλ,μ(z) and gλ,η(z) have infinitely many singular values for all b>0, b≠1
Biodegradation of phenanthrene by Pseudomonas sp BZ-3, isolated from crude oil contaminated soil
No full textA phenanthrene (PHE) degrading bacterium strain BZ-3 was isolated from the crude oil contaminated soil in Binzhou, China. The isolate was identified as Pseudomonas sp. BZ-3 on the basis of 16S rRNA gene sequence. Various experiments were conducted to investigate the effect of pH, salinity and PHE concentration on the degradation efficiency of PHE. The degradation efficiency and degradation metabolites of PHE were detected by using GC-MS and HPLC-MS analyses. The strain BZ-3 could degrade 75% of PHE at an initial concentration of 50 mg/L under 20 g/L salinity in 7 days. PHE degradation kinetics was estimated in a first-order degradation rate model and the rate coefficient was calculated as 0.108 d(-1). On the basis of the identified degradation metabolites, the strain BZ-3 could degrade PHE in the salicylate metabolic pathway. In a mixture system consisting of PHE and other PAHs including naphthalene (NA), anthracene (ANTH), and pyrene (PYR), the strain BZ-3 showed an efficiently degradation capability. Further study showed that the strain BZ-3 could also use NA, ANTH, PYR, xylene, 1-hydroxy-2-naphthoic acid, and hexane as the sole carbon and energy source, but did not grow on nitrobenzene-containing medium. (C) 2014 Elsevier Ltd. All rights reserved.A phenanthrene (PHE) degrading bacterium strain BZ-3 was isolated from the crude oil contaminated soil in Binzhou, China. The isolate was identified as Pseudomonas sp. BZ-3 on the basis of 16S rRNA gene sequence. Various experiments were conducted to investigate the effect of pH, salinity and PHE concentration on the degradation efficiency of PHE. The degradation efficiency and degradation metabolites of PHE were detected by using GC-MS and HPLC-MS analyses. The strain BZ-3 could degrade 75% of PHE at an initial concentration of 50 mg/L under 20 g/L salinity in 7 days. PHE degradation kinetics was estimated in a first-order degradation rate model and the rate coefficient was calculated as 0.108 d(-1). On the basis of the identified degradation metabolites, the strain BZ-3 could degrade PHE in the salicylate metabolic pathway. In a mixture system consisting of PHE and other PAHs including naphthalene (NA), anthracene (ANTH), and pyrene (PYR), the strain BZ-3 showed an efficiently degradation capability. Further study showed that the strain BZ-3 could also use NA, ANTH, PYR, xylene, 1-hydroxy-2-naphthoic acid, and hexane as the sole carbon and energy source, but did not grow on nitrobenzene-containing medium. (C) 2014 Elsevier Ltd. All rights reserved
The Influence of a Pharmaceutical Intermediate on BZ Oscillating Reaction
No full textAbstract: Because there are cyclical phenomenons in lives so that the influence of the medicine on oscillating reaction is becoming a hotspot.The author prepares a pharmaceutical intermediate. It is 2,6-dihydroxy-4-methylpyrimidine.In this paper the influence of the pharmaceutical intermediate on BZ oscillation system have been studied at different temperature and different concentration. For instance, dropping the concentration of 0.01mol/Lpharmaceutical intermediate before and after, apparent activation energy E and E’ of the systems are 68094J/mol and 71786J/mol.Higher temperature and higher concentration,oscillating cycles and amplitude are lower.</jats:p
On Ideals Annihilating the Toral Class of BP<sub>*</sub>((<i>BZ/P<sup>K</sup>)<sup>N</sup></i>)
No full textAbstractA sequence of ideals Ik,n ⊆ BP* is introduced, with the property: Ik,n ⊆ Ann(γk,n), where γk,n is the toral class of the Brown-Peterson homology of the n-fold product BZ/pk × ··· × BZ/pk. These ideals seem to play an interesting and yet unclear role in understanding Ann(γk,n). They are defined by using the formal group law of the Brown-Peterson spectrum BP, and some of their elementary properties are established. By using classical theorems of Landweber and of Ravenel-Wilson, the author computes the radicals of Ik,n and Ann(γk,n), and discusses a few examples.</jats:p
Interplanetary magnetic field rotations followed from L1 to the ground : the response of the Earth's magnetosphere as seen by multi-spacecraft and ground-based observations
Get PDFA study of the interaction of solar wind magnetic field rotations with the Earth's magnetosphere is performed. For this event there is, for the first time, a full coverage over the dayside magnetosphere with multiple (multi)spacecraft missions from dawn to dusk, combined with ground magnetometers, radar and an auroral camera, this gives a unique coverage of the response of the Earth's magnetosphere. After a long period of southward IMF Bz and high dynamic pressure of the solar wind, the Earth's magnetosphere is eroded and compressed and reacts quickly to the turning of the magnetic field. We use data from the solar wind monitors ACE and Wind and from magnetospheric missions Cluster, THEMIS, DoubleStar and Geotail to investigate the behaviour of the magnetic rotations as they move through the bow shock and magnetosheath. The response of the magnetosphere is investigated through ground magnetometers and auroral keograms. It is found that the solar wind magnetic field drapes over the magnetopause, while still co-moving with the plasma flow at the flanks. The magnetopause reacts quickly to IMF Bz changes, setting up field aligned currents, poleward moving aurorae and strong ionospheric convection. Timing of the structures between the solar wind, magnetosheath and the ground shows that the advection time of the structures, using the solar wind velocity, correlates well with the timing differences between the spacecraft. The reaction time of the magnetopause and the ionospheric current systems to changes in the magnetosheath Bz seem to be almost immediate, allowing for the advection of the structure measured by the spacecraft closest to the magnetopause
Tell us our story: Understanding 'religion and violence' in multiple contexts of learning
No full textThis article raises the question about how definitions of religion and violence can be understood as links to the context in which they are formulated. The focus is on the context of academic learning. Understanding a definition as a micro-narrative that reflects the cultural 'archive', the author uses two academic contexts (i.e. Utrecht, The Netherlands and Jakarta, Indonesia) to show how religion and violence are differently understood. These differences are taken as significant information for understanding how the topic of 'religion and violence' is related to cultural understandings of the place of religion in society. The question is raised how 'narrative learning' can help as a strategy to raise awareness about the preconditioning of (academic) definitions of 'religion and violence'
Comparison of Gd-Bz-TTDA, Gd-EOB-DTPA, and Gd-BOPTA for dynamic MR imaging of the liver in rat models
No full textAbstractTo evaluate the competitive potential of a new lipophilic paramagnetic complex, Gd-Bz-TTDA [4-benzyl-3,6,10-tri (carboxymethyl)-3,6,10-triazado-decanedioic acid] compared with two other commercially available MR hepatobiliary contrast agents, gadobenate dimeglumine (Gd-BOPTA) and gadoxetic acid (Gd-EOB-DTPA), dynamic MR imaging studies were performed on normal and hepatocellular carcinoma (HCC) rat models using a 1.5-Tesla MR scanner. The results indicate that normal rats that were injected with 0.1 mmol/kg Gd-Bz-TTDA showed significantly more intense and persistent liver enhancement than those that were injected with the same dose of Gd-EOB-DTPA or Gd-BOPTA. All of these agents showed similar enhancement patterns in the implanted HCC. The liver-lesion contrast-to-noise ratios were higher and more persistent in rats that were injected with Gd-Bz-TTDA. These results indicate that Gd-Bz-TTDA is comparable with the commercially available hepatobiliary agents, Gd-EOB-DTPA and Gd-BOPTA, and can result in more intense and prolonged liver enhancement while still providing better liver-lesion discrimination. These results warrant further large-scale studies
Different morphologies of self-assembled nanofibers fabricated with amphiphilic low-molecular-weight azopyridinium salts
No full textSelf-assembled nanofibers with different morphologies were successfully fabricated using amphiphilic low-molecular-weight (LMW) azopyridinium compounds having hydrophobic substituents on benzene groups. The possible driving force and self-assembly principles in nanofiber formation processes were proposed based on measurements of X-ray diffraction (XRD), UV-vis absorption spectra and polarizing optical microscopy (POM). The complicated stackings between azopyridinium salts which were constructed by three aromatic units in azopyridinium molecules, i.e. the stackings between benzene groups (Bz-Bz), pyridine groups (Py-Py) and those of benzene with pyridine groups (Bz-Py), mainly acted as the driving force for formation of LMW-AzPy nanofibers. The changed steric hindrance and hydrophobic properties of substituents on benzene groups resulted in the two aggregation types, head-tail and head-head-tail-tail, of LMW-AzPy molecules. In these cases, the head and tail are hydrophilic and hydrophobic parts of LMW-AzPys molecules, respectively. The analyses and understanding of the driving force and aggregation types of LMW-AzPy nanofibers provides references for fabrication of supramolecularly self-assembled nanofibers with controllable behaviours.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000326056600143&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Chemistry, MultidisciplinarySCI(E)EI4ARTICLE4422155-22159
Origination of Ds elements from Ac elements in maize: characterization of Ac derivatives from bz-m39(Ac)
No full textThe maize genome contains a large number of both DNA transposons and retrotransposons. It is already known that retrotransposons are located in the highly methylated intergenic regions where recombination does not take place. However, DNA transposons are located in the eukaryotic regions of the maize genome, where they are able to interact with the host genes. It has been recently known that two transposable elements in direct orientation in the same chromosome may recombine occasionally with each other, which leads to the deletion of the intervening fragment. Based on this fact, it would be interesting to find out whether two elements in different homologues are able to recombine at meiosis. A series of Ac derivatives that originated de novo from bz-m39 (Ac) have been generated previously by Dr Dooner's lab. Some of these Ds derivatives appear to be large ([greater than] 4kb) based on Southern blots. It may be possible to recombine two Ds elements with non-overlapping deletions to reconstruct a 4565-bp Ac element. Hence these derivatives' exact sequence composition needs to be defined. In this research project, I characterized 23 Ac-derivatives, and the results indicate that most of these derivatives are composed of fragmented transposon structures. Some of them are Ds elements with or without filler DNA; some of them are single-ended fractured Ac (fAc) elements with either 5' or 3' missing ends, yet not transposed, which have not been reported before, indicating that Ac may undergo not only internal deletions but also terminal deletions that are sometimes accompanied by deletion of its flanking sequence. Microhomology, which is the main mechanism to explain the non-homologous end-joining repair of deletions in Ac, was discovered at the deletion junctions of most of these derivatives. The next step is to select suitable derivatives to carry out the recombination experiment by crossing and measuring the frequency of meiotic recombination within the transposable element (TE) in bz, which will be compared then to recombination in bz. Here, I present the molecular analysis of these 23 derivatives.M.S.Includes bibliographical references (p. 44-46)
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