| 1. |
- George, T. S., et al.
(författare)
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Organic phosphorus in the terrestrial environment : a perspective on the state of the art and future priorities
- 2018
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Ingår i: Plant and Soil. - : Springer Netherlands. - 0032-079X .- 1573-5036. ; 427:1-2, s. 191-208
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Tidskriftsartikel (refereegranskat)abstract
- Background: The dynamics of phosphorus (P) in the environment is important for regulating nutrient cycles in natural and managed ecosystems and an integral part in assessing biological resilience against environmental change. Organic P (P-o) compounds play key roles in biological and ecosystems function in the terrestrial environment being critical to cell function, growth and reproduction.Scope: We asked a group of experts to consider the global issues associated with P-o in the terrestrial environment, methodological strengths and weaknesses, benefits to be gained from understanding the P-o cycle, and to set priorities for P-o research.Conclusions: We identified seven key opportunities for P-o research including: the need for integrated, quality controlled and functionally based methodologies; assessment of stoichiometry with other elements in organic matter; understanding the dynamics of P-o in natural and managed systems; the role of microorganisms in controlling P-o cycles; the implications of nanoparticles in the environment and the need for better modelling and communication of the research. Each priority is discussed and a statement of intent for the P-o research community is made that highlights there are key contributions to be made toward understanding biogeochemical cycles, dynamics and function of natural ecosystems and the management of agricultural systems.
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| 2. |
- Braud, N., et al.
(författare)
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Cleaning and tailoring the Pt3Sn(111) surface for surface experiments
- 2023
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Ingår i: Surface Science. - : Elsevier. - 0039-6028 .- 1879-2758. ; 732
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Tidskriftsartikel (refereegranskat)abstract
- The cleaning process of the bimetallic Pt3Sn(111) surface has been studied by means of low-energy electron microscopy (LEEM), microspot low-energy electron diffraction (mu.-LEED), and X-ray photoemission electron microscopy (XPEEM). Different cleaning procedures, performed under ultra-high vacuum conditions (UHV), including sputtering with argon ions and repeated cycles of annealing up to 1500 K were investigated. In this work, we show that a clean Pt3Sn(111) surface of high structural quality with a sharp and brilliant (2 x 2) bulk reconstruction in LEED as well as a perfectly smooth surface with terraces of micron size can be achieved by sputtering, annealing at very high temperatures, followed by a subsequent slow (0.09 K/s) and careful cooling procedure. Additionally, we show the possibility of tailoring the Sn concentration in the topmost layers of Pt3Sn(111) as a function of annealing temperature and subsequent cooling rate. Structural changes of the surface are induced by Sn segregation combined with a surface order-disorder transition at 1340 K. Moreover, two new surface reconstructions depending on the cooling rate are reported.
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| 3. |
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| 4. |
- Duraj, F, et al.
(författare)
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Tarmtransplantation
- 1998
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Ingår i: Läkartidningen. ; 28, s. 3172-
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 5. |
- Bui, Christine L, et al.
(författare)
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Validation of acute liver injury cases in a population-based cohort study of oral antimicrobial users
- 2014
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Ingår i: Current Drug Safety. - : Bentham Science Publishers Ltd.. - 1574-8863 .- 2212-3911. ; 9:1, s. 23-28
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Tidskriftsartikel (refereegranskat)abstract
- We conducted a cohort study of acute, noninfectious liver injury among oral antimicrobial users. Potential cases were identified in the HealthCore Integrated Research Database (HIRD(SM)) population between July 1, 2001, and March 31, 2009, using ICD-9-CM codes primarily for acute and subacute necrosis of the liver, hepatic coma, and unspecified hepatitis.Liver test results were used to confirm case status according to published criteria. Two physician reviewers experienced in studying acute liver injury (blinded to study drug exposures) evaluated data abstracted from hospital and emergency department records to validate potential cases. Of 715 potential cases having claims associated with any of the primary screening codes, 312 (44%) were valid cases, 108 (15%) were not cases, and 295 (41%) were of uncertain status (records inadequate for validation). Among potential cases with adequate medical records, the PPV for presence of any of the primary codes was 74% (95% CI, 70%-78%). The highest PPV for a single code was for acute and subacute necrosis of the liver (84%; 95% CI, 77%-90%).Evaluation of cases of noninfectious liver injury using hospital and emergency department medical records continues to represent the preferred approach in studies using insurance claims data.
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| 6. |
- Kaye, James A, et al.
(författare)
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Risk of acute liver injury associated with the use of moxifloxacin and other oral antimicrobials : a retrospective, population-based cohort study
- 2014
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Ingår i: Pharmacotherapy. - : Wiley. - 0277-0008 .- 1875-9114. ; 34:4, s. 336-349
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Tidskriftsartikel (refereegranskat)abstract
- STUDY OBJECTIVE: To estimate the incidence and relative risk of a hospitalization or emergency visit for noninfectious liver injury in users of eight oral antimicrobials-amoxicillin, amoxicillin-clavulanic acid, clarithromycin, cefuroxime, doxycycline, levofloxacin, moxifloxacin, telithromycin-compared with nonusers of these antimicrobials.DESIGN: Retrospective, observational cohort study with a nested case-control analysis.DATA SOURCE: HealthCore Integrated Research Database.PATIENTS: Adults with continuous health plan enrollment for at least 6 months before study entry who had a new dispensing of a study antimicrobial between July 1, 2001, and March 31, 2009. Cases had diagnoses indicating noninfectious liver injury during follow-up. To control for potentially confounding risk factors, 10 controls at risk for liver injury during follow-up were matched to each case by age, sex, and event date (liver injury date of the case), and analyses were adjusted for medical history, concomitant drugs, and health care service use.MEASUREMENTS AND MAIN RESULTS: Two physician reviewers (blind to exposure) validated the cases. Among 1.3 million antimicrobial users, we identified 607 cases of liver injury, including 82 cases of severe hepatocellular injury and 11 cases of liver failure. Liver injury incidence in nonusers of study antimicrobials was 35/100,000 person-years (95% confidence interval [CI] 29-42/100,000 person-years). For valid cases, the adjusted relative risk among current users of multiple antimicrobials was 3.2 (95% CI 1.6-6.7). Levofloxacin had the highest relative risk for current single use (3.2, 95% CI 1.8-5.8). Relative risks were also elevated for amoxicillin-clavulanic acid (2.5, 95% CI 1.3-5.0), doxycycline (2.5, 95% CI 1.2-5.2), moxifloxacin (2.3, 95% CI 1.1-4.7), and amoxicillin (2.3, 95% CI 1.1-4.7).CONCLUSION: The results support a comparatively high adjusted relative risk of liver injury among patients exposed concurrently to multiple antimicrobials and modest elevations in the risk for several antimicrobials used alone; however, we found little evidence of any strong effect of commonly used antimicrobials on the risk of liver injury.
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| 8. |
- Sheldrake, Merlin, et al.
(författare)
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Arbuscular mycorrhizal fungal community composition is altered by long-term litter removal but not litter addition in a lowland tropical forest
- 2017
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Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 214:1, s. 455-467
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Tidskriftsartikel (refereegranskat)abstract
- Tropical forest productivity is sustained by the cycling of nutrients through decomposing organic matter. Arbuscular mycorrhizal (AM) fungi play a key role in the nutrition of tropical trees, yet there has been little experimental investigation into the role of AM fungi in nutrient cycling via decomposing organic material in tropical forests. We evaluated the responses of AM fungi in a long-term leaf litter addition and removal experiment in a tropical forest in Panama. We described AM fungal communities using 454-pyrosequencing, quantified the proportion of root length colonised by AM fungi using microscopy, and estimated AM fungal biomass using a lipid biomarker. AM fungal community composition was altered by litter removal but not litter addition. Root colonisation was substantially greater in the superficial organic layer compared with the mineral soil. Overall colonisation was lower in the litter removal treatment, which lacked an organic layer. There was no effect of litter manipulation on the concentration of the AM fungal lipid biomarker in the mineral soil. We hypothesise that reductions in organic matter brought about by litter removal may lead to AM fungi obtaining nutrients from recalcitrant organic or mineral sources in the soil, besides increasing fungal competition for progressively limited resources.
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