| 1. |
- Feuerbacher, Michael, et al.
(författare)
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The Samson phase, β-Mg2Al3, revisited
- 2007
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Ingår i: Zeitschrift fur Kristallographie. - : Walter de Gruyter GmbH. - 0044-2968. ; 222:6, s. 259-288
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Forskningsöversikt (refereegranskat)abstract
- The Al-Mg phase diagram has been reinvestigated in the vicinity of the stability range of the Samson phase, β-Mg2Al3 (cF1168). For the composition Mg38.5Al61.5, this cubic phase, space group Fd3̄m (no 227), a = 28.242(1) Å, V = 22526(2) Å3, undergoes at 214°C a first-order phase transition to rhombohedral β′-Mg2Al3, (hR293), a = 19.968(1) Å, c = 48.9114(8) Å, V = 16889(2) Å3, (i.e. 22519 Å3 for the equivalent cubic unit cell) space group R3m (no 160), a subgroup of index four of Fd3̄m. The structure of the β-phase has been redetermined at ambient temperature as well as in situ at 400°C. It essentially agrees with Samson's model, even in most of the many partially occupied and split positions. The structure of β′-Mg 2Al3 is closely related to that of the β-phase. Its atomic sites can be derived from those of the β-phase by group-theoretical considerations. The main difference between the two structures is that all atomic sites are fully occupied in case of the β′-phase. The reciprocal space, Bragg as well as diffuse scattering, has been explored as function of temperature and the β- to β′-phase transition was studied in detail. The microstructures of both phases have been analyzed by electron microscopy and X-ray topography showing them highly defective. Finally, the thermal expansion coefficients and elastic parameters have been determined. Their values are somewhere in between those of Al and Mg.
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| 2. |
- Harlid, Sophia, 1978-, et al.
(författare)
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Risk‐predictive and diagnostic biomarkers for colorectal cancer : a systematic review of studies using pre‐diagnostic blood samples collected in prospective cohorts and screening settings
- 2021
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Ingår i: Cancers. - : MDPI. - 2072-6694. ; 13:17
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Forskningsöversikt (refereegranskat)abstract
- This systematic review summarizes the evidence for blood‐based colorectal cancer biomarkers from studies conducted in pre‐diagnostic, asymptomatic settings. Of 1372 studies initially identified, the final selection included 30 studies from prospective cohorts and 23 studies from general screening settings. Overall, the investigations had high quality but considerable variability in data analysis and presentation of results, and few biomarkers demonstrated a clinically relevant discriminatory ability. One of the most promising biomarkers was the anti‐p53 antibody, with consistent findings in one screening cohort and in the 3–4 years prior to diagnosis in two prospective cohort studies. Proteins were the most common type of biomarker assessed, particularly carcinoembryonic antigen (CEA) and C‐reactive protein (CRP), with modest results. Other potentially promising biomarkers included proteins, such as AREG, MIC‐1/GDF15, LRG1 and FGF‐21, metabolites and/or metabolite profiles, non‐coding RNAs and DNA methylation, as well as re‐purposed routine lab tests, such as ferritin and the triglyceride–glucose index. Biomarker panels generally achieved higher discriminatory performance than single markers. In conclusion, this systematic review highlighted anti‐p53 antibodies as a promising blood‐based biomarker for use in colorectal cancer screening panels, together with other specific proteins. It also underscores the need for validation of promising biomarkers in independent pre‐diagnostic settings.
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