| 1. |
- Dahlin, T., et al.
(författare)
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Geoelectrical resistivity monitoring for localizing gas at Landfills
- 2009
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Ingår i: Near Surface 2009 : 15th European Meeting of Environmental and Engineering Geophysics - 15th European Meeting of Environmental and Engineering Geophysics. - 9073781728 - 9789073781726
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Konferensbidrag (refereegranskat)abstract
- In order to assess the potential of electrical resistivity for imaging gas migration at landfills, two relatively well-known sites - one bioreactor landfill and a conventional landfill - have been monitored successively. A three-dimensional resistivity image could be constructed every two hour on both sites. Meteorological parameters were monitored at the same time, with one measurement taken every hour. Methane concentration was measured in the air at several occasions, the pore pressure was monitored at two locations and some relative estimations of moisture in the top layer were made at the second site. The results show imperfect but interesting correlations between the different parameters and give a hint of how the method could be refined. The resistivity depends on several parameters, but the areas where the resistivity is most variable seem to be clearly related to higher gas emissions.
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| 2. |
- Börjesson, Stefan, 1979-, et al.
(författare)
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Detection of an IMI-2 carbapenemase-producing Enterobacter asburiae at a Swedish feed mill
- 2022
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Ingår i: Frontiers in Microbiology. - : Frontiers Media S.A.. - 1664-302X. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Occurrence of multidrug resistant Enterobacteriaceae in livestock is of concern as they can spread to humans. A potential introduction route for these bacteria to livestock could be animal feed. We therefore wanted to identify if Escherichia spp., Enterobacter spp., Klebsiella spp., or Raoutella spp. with transferable resistance to extended spectrum cephalosporins, carbapenems or colistin could be detected in the environment at feed mills in Sweden. A second aim was to compare detected isolates to previous described isolates from humans and animals in Sweden to establish relatedness which could indicate a potential transmission between sectors and feed mills as a source for antibiotic resistant bacteria. However, no isolates with transferable resistance to extended-cephalosporins or colistin could be identified, but one isolate belonging to the Enterobacter cloacae complex was shown to be carbapenem-resistant and showing carbapenemase-activity. Based on sequencing by both short-read Illumina and long-read Oxford Nanopore MinIon technologies it was shown that this isolate was an E. asburiae carrying a bla IMI-2 gene on a 216 Kbp plasmid, designated pSB89A/IMI-2, and contained the plasmid replicons IncFII, IncFIB, and a third replicon showing highest similarity to the IncFII(Yp). In addition, the plasmid contained genes for various functions such as plasmid segregation and stability, plasmid transfer and arsenical transport, but no additional antibiotic resistance genes. This isolate and the pSB89A/IMI-2 was compared to three human clinical isolates positive for bla IMI-2 available from the Swedish antibiotic monitoring program Swedres. It was shown that one of the human isolates carried a plasmid similar with regards to gene content to the pSB89A/IMI-2 except for the plasmid transfer system, but that the order of genes was different. The pSB89A/IMI-2 did however share the same transfer system as the bla IMI-2 carrying plasmids from the other two human isolates. The pSB89A/IMI-2 was also compared to previously published plasmids carrying bla IMI-2, but no identical plasmids could be identified. However, most shared part of the plasmid transfer system and DNA replication genes, and the bla IMI-2 gene was located next the transcription regulator imiR. The IS3-family insertion element downstream of imiR in the pSB89A was also related to the IS elements in other bla IMI-carrying plasmids.
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| 3. |
- Lindsjö, Martin, et al.
(författare)
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Novel Compounds Sn14In10P22I8 and Sn14In10P21.2I8 with Clathrate-I Structure: Synthesis and Crystal and Electronic Structure
- 2001
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Ingår i: Journal of Solid State Chemistry. - : Elsevier BV. - 0022-4596 .- 1095-726X. ; 161:2, s. 232-242
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Tidskriftsartikel (refereegranskat)abstract
- Two new supramolecular pnictidehalides Sn10In14P22I8 (I) anti Sn14In10P21.2I8 (II) have been synthesized using a standard ampoule technique. Both compounds possess the clathrate I type of structure. I crystallizes in the cubic space group Pm (3) over barn (No. 223) with the unit cell parameter a = 11.0450(7) (Z = 1) while II reveals a complicated superstructure (space group P4(2)/m (No. 84), a = 24.745(3) Angstrom, c = 11.067(1) Angstrom, Z = 5) resulting from the partial ordering of vacancies at phosphorus sites. The crystal structures have been solved based on single-crystal X-ray diffraction data sets (omega -2 theta) scans, least-squares refinement against F-2) to R = 0.0376 (Sn10In14P22I8) and R = 0.0569 (Sn14In10P21.2I8). In both structures metal anti phosphorus atoms form a cationic clathrate I framework hosting iodine atoms in the cavities. The composition of both phases complies with the Zintl-Klemm formalism which justifies the existence of vacancies in the structure of II. The Sn-119 Mossbauer spectroscopy data together with the results of the band structure calculations suggest that the electron density on tin atoms is reduced in favor of bands, which lie just below the Fermi level and must define electronic properties of the compounds in question. The differences in the crystal and electronic structures of the cationic tin clathrates are discussed.
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