| 1. |
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| 2. |
- Lawrenson, Kate, et al.
(författare)
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Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus
- 2016
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 × 10-20), ER-negative BC (P=1.1 × 10-13), BRCA1-associated BC (P=7.7 × 10-16) and triple negative BC (P-diff=2 × 10-5). Genotype-gene expression associations are identified for candidate target genes ANKLE1 (P=2 × 10-3) and ABHD8 (P<2 × 10-3). Chromosome conformation capture identifies interactions between four candidate SNPs and ABHD8, and luciferase assays indicate six risk alleles increased transactivation of the ADHD8 promoter. Targeted deletion of a region containing risk SNP rs56069439 in a putative enhancer induces ANKLE1 downregulation; and mRNA stability assays indicate functional effects for an ANKLE1 3′-UTR SNP. Altogether, these data suggest that multiple SNPs at 19p13 regulate ABHD8 and perhaps ANKLE1 expression, and indicate common mechanisms underlying breast and ovarian cancer risk.
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| 3. |
- Abend, Sven, et al.
(författare)
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Terrestrial very-long-baseline atom interferometry : Workshop summary
- 2024
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Ingår i: AVS Quantum Science. - : American Institute of Physics (AIP). - 2639-0213. ; 6:2
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Forskningsöversikt (refereegranskat)abstract
- This document presents a summary of the 2023 Terrestrial Very-Long-Baseline Atom Interferometry Workshop hosted by CERN. The workshop brought together experts from around the world to discuss the exciting developments in large-scale atom interferometer (AI) prototypes and their potential for detecting ultralight dark matter and gravitational waves. The primary objective of the workshop was to lay the groundwork for an international TVLBAI proto-collaboration. This collaboration aims to unite researchers from different institutions to strategize and secure funding for terrestrial large-scale AI projects. The ultimate goal is to create a roadmap detailing the design and technology choices for one or more kilometer--scale detectors, which will be operational in the mid-2030s. The key sections of this report present the physics case and technical challenges, together with a comprehensive overview of the discussions at the workshop together with the main conclusions.
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| 4. |
- Aoyagi, Satoka, et al.
(författare)
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Peptide structural analysis using continuous Ar cluster and C60 ion beams
- 2013
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Ingår i: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 405:21, s. 6621-6628
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Tidskriftsartikel (refereegranskat)abstract
- A novel application of time-of-flight secondary ion mass spectrometry (ToF-SIMS) with continuous Ar cluster beams to peptide analysis was investigated. In order to evaluate peptide structures, it is necessary to detect fragment ions related to multiple neighbouring amino acid residues. It is, however, difficult to detect these using conventional ToF-SIMS primary ion beams such as Bi cluster beams. Recently, C60 and Ar cluster ion beams have been introduced to ToF-SIMS as primary ion beams and are expected to generate larger secondary ions than conventional ones. In this study, two sets of model peptides have been studied: (des-Tyr)-Leuenkephalin and (des-Tyr)-Met-enkephalin (molecular weights are approximately 400 Da), and [Asn1 Val5]-angiotensin II and [Val5]-angiotensin I (molecular weights are approximately 1,000 Da) in order to evaluate the usefulness of the large cluster ion beams for peptide structural analysis. As a result, by using the Ar cluster beams, peptide molecular ions and large fragment ions, which are not easily detected using conventional ToF-SIMS primary ion beams such as Bi3+, are clearly detected. Since the large fragment ions indicating amino acid sequences of the peptides are detected by the large cluster beams, it is suggested that the Ar cluster and C60 ion beams are useful for peptide structural analysis.
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| 5. |
- Bassan, Paul, et al.
(författare)
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The inherent problem of transflection-mode infrared spectroscopic microscopy and the ramifications for biomedical single point and imaging applications.
- 2013
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Ingår i: The Analyst. - : Royal Society of Chemistry (RSC). - 1364-5528 .- 0003-2654. ; 138:1, s. 144-57
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Tidskriftsartikel (refereegranskat)abstract
- Transflection-mode FTIR spectroscopy has become a popular method of measuring spectra from biomedical and other samples due to the relative low cost of substrates compared to transmission windows, and a higher absorbance due to a double pass through the same sample approximately doubling the effective path length. In this publication we state an optical description of samples on multilayer low-e reflective substrates. Using this model we are able to explain in detail the so-called electric-field standing wave effect and rationalise the non-linear change in absorbance with sample thickness. The ramifications of this non-linear change, for imaging and classification systems, where a model is built from tissue sectioned at a particular thickness and compared with tissue of a different thickness are discussed. We show that spectra can be distorted such that classification fails leading to inaccurate tissue segmentation which may have subsequent implications for disease diagnostics applications.
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| 6. |
- Couch, Fergus J., et al.
(författare)
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Identification of four novel susceptibility loci for oestrogen receptor negative breast cancer
- 2016
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Ingår i: Nature Communications. - : NATURE PUBLISHING GROUP. - 2041-1723. ; 7:11375, s. 1-13
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Tidskriftsartikel (refereegranskat)abstract
- Common variants in 94 loci have been associated with breast cancer including 15 loci with genome-wide significant associations (P<5 x 10(-8)) with oestrogen receptor (ER)-negative breast cancer and BRCA1-associated breast cancer risk. In this study, to identify new ER-negative susceptibility loci, we performed a meta-analysis of 11 genome-wide association studies (GWAS) consisting of 4,939 ER-negative cases and 14,352 controls, combined with 7,333 ER-negative cases and 42,468 controls and 15,252 BRCA1 mutation carriers genotyped on the iCOGS array. We identify four previously unidentified loci including two loci at 13q22 near KLF5, a 2p23.2 locus near WDR43 and a 2q33 locus near PPIL3 that display genome-wide significant associations with ER-negative breast cancer. In addition, 19 known breast cancer risk loci have genome-wide significant associations and 40 had moderate associations (P<0.05) with ER-negative disease. Using functional and eQTL studies we implicate TRMT61B and WDR43 at 2p23.2 and PPIL3 at 2q33 in ER-negative breast cancer aetiology. All ER-negative loci combined account for similar to 11% of familial relative risk for ER-negative disease and may contribute to improved ER-negative and BRCA1 breast cancer risk prediction.
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| 7. |
- Dorschel, Boris, et al.
(författare)
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The International Bathymetric Chart of the Southern Ocean Version 2
- 2022
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Ingår i: Scientific Data. - : Springer Science and Business Media LLC. - 2052-4463. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- The Southern Ocean surrounding Antarctica is a region that is key to a range of climatic and oceanographic processes with worldwide effects, and is characterised by high biological productivity and biodiversity. Since 2013, the International Bathymetric Chart of the Southern Ocean (IBCSO) has represented the most comprehensive compilation of bathymetry for the Southern Ocean south of 60 degrees S. Recently, the IBCSO Project has combined its efforts with the Nippon Foundation - GEBCO Seabed 2030 Project supporting the goal of mapping the world's oceans by 2030. New datasets initiated a second version of IBCSO (IBCSO v2). This version extends to 50 degrees S (covering approximately 2.4 times the area of seafloor of the previous version) including the gateways of the Antarctic Circumpolar Current and the Antarctic circumpolar frontal systems. Due to increased (multibeam) data coverage, IBCSO v2 significantly improves the overall representation of the Southern Ocean seafloor and resolves many submarine landforms in more detail. This makes IBCSO v2 the most authoritative seafloor map of the area south of 50 degrees S.
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| 8. |
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| 9. |
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| 10. |
- Fletcher, John, 1978, et al.
(författare)
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ToF-SIMS Studies of Sulfuric Acid Hydrate Films
- 2004
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Ingår i: Journal of Physical Chemistry B. - 1520-5207 .- 1520-6106. ; 108:19, s. 5960-5966
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Tidskriftsartikel (refereegranskat)abstract
- A variety of sulfuric acid hydrate films, formed by the co-deposition of SO3 and H2O on a cooled substrate, have been analyzed using time-of-flight secondary ion mass spectrometry (ToF-SIMS). The films were produced using procedures developed in recent infrared spectroscopic studies. Spectra have been shown to consist of a series of identifiable fragments, the change in intensities of which can be related to changes in temperature and the relative abundance of H2O during the deposition of the film under UHV conditions. Depth profiling of the films shows clear evidence of separate surface species on some films and supports the existence of surface molecular hydrates over a stable bulk hydrate film
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| 11. |
- Fletcher, John, 1978, et al.
(författare)
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Uncovering new challenges in bio-analysis with ToF-SIMS
- 2008
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Ingår i: Applied Surface Science. - : Elsevier BV. - 0169-4332. ; 255:4, s. 1264-1270
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Konferensbidrag (refereegranskat)abstract
- The introduction of cluster ion beams for routine SIMS analysis has greatly improved the prospects for characterising biological samples. The ultimate quality of the secondary ion image remains limited by the efficiency of the primary beam. Without overcoming the low ionisation probabilities associated with SIMS, the highest lateral resolution available for molecular imaging becomes limited by the statistical probability of any ions being generated from the area of the pixel. C(60)(+) primary ions are currently the most efficient available for routine analysis but although commercial systems have been demonstrated to produce spot sizes under 200 nm, focusing the beam produced in such electron impact sources results in rather low ion currents. The time scale for such high lateral resolution analysis can become impractical on conventional time-of-flight instruments. Molecular depth pro. ling capability has been revealed using SF(5)(+) and C(60)(+) ion beams and recent work has advanced the technique by combining the pro. ling and imaging abilities of these high efficiency projectiles to generate 3D molecular maps of biological systems. In this paper we discuss the challenges associated with 2D and 3D bio-analysis with emphasis on how instrumental advances aid such investigations yet demonstrating the obstacles that need to be overcome using a range of model and real world biological samples. We discuss complications with the biological matrix, challenges in manipulating and visualising the data and look at how instrumental advantages might aid the routine generation of these 3D molecular maps. (C) 2008 Elsevier B. V. All rights reserved.
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| 12. |
- Haidet-Phillips, Amanda M, et al.
(författare)
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Gene Profiling of Human Induced Pluripotent Stem Cell-Derived Astrocyte Progenitors Following Spinal Cord Engraftment.
- 2014
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Ingår i: Stem cells translational medicine. - : Oxford University Press (OUP). - 2157-6580 .- 2157-6564. ; 3:5, s. 575-585
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Tidskriftsartikel (refereegranskat)abstract
- The generation of human induced pluripotent stem cells (hiPSCs) represents an exciting advancement with promise for stem cell transplantation therapies as well as for neurological disease modeling. Based on the emerging roles for astrocytes in neurological disorders, we investigated whether hiPSC-derived astrocyte progenitors could be engrafted to the rodent spinal cord and how the characteristics of these cells changed between in vitro culture and after transplantation to the in vivo spinal cord environment. Our results show that human embryonic stem cell- and hiPSC-derived astrocyte progenitors survive long-term after spinal cord engraftment and differentiate to astrocytes in vivo with few cells from other lineages present. Gene profiling of the transplanted cells demonstrates the astrocyte progenitors continue to mature in vivo and upregulate a variety of astrocyte-specific genes. Given this mature astrocyte gene profile, this work highlights hiPSCs as a tool to investigate disease-related astrocyte biology using in vivo disease modeling with significant implications for human neurological diseases currently lacking animal models.
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| 13. |
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| 14. |
- Hirao, Yuki, et al.
(författare)
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OGLE-2017-BLG-0406 : Spitzer Microlens Parallax Reveals Saturn-mass Planet Orbiting M-dwarf Host in the Inner Galactic Disk
- 2020
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Ingår i: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 160:2
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Tidskriftsartikel (refereegranskat)abstract
- We report the discovery and analysis of the planetary microlensing event OGLE-2017-BLG-0406, which was observed both from the ground and by the Spitzer satellite in a solar orbit. At high magnification, the anomaly in the light curve was densely observed by ground-based-survey and follow-up groups, and it was found to be explained by a planetary lens with a planet/host mass ratio of q = 7.0 x 10(-4) from the light-curve modeling. The ground-only and Spitzer-only data each provide very strong one-dimensional (1D) constraints on the 2D microlens parallax vector pi(E). When combined, these yield a precise measurement of pi(E) and of the masses of the host M-host = 0.56 +/- 0.07 M-circle dot and planet M-planet = 0.41 +/- 0.05 M-Jup. The system lies at a distance D-L = 5.2 +/- 0.5 kpc from the Sun toward the Galactic bulge, and the host is more likely to be a disk population star according to the kinematics of the lens. The projected separation of the planet from the host is a(perpendicular to) = 3.5 +/- 0.3 au (i.e., just over twice the snow line). The Galactic-disk kinematics are established in part from a precise measurement of the source proper motion based on OGLE-IV data. By contrast, the Gaia proper-motion measurement of the source suffers from a catastrophic 10 sigma error.
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| 15. |
- Kotze, Helen L., et al.
(författare)
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ToF-SIMS as a tool for metabolic profiling small biomolecules in cancer systems
- 2013
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Ingår i: Surface and Interface Analysis. - 1096-9918 .- 0142-2421. ; 45:1, s. 277-281
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Tidskriftsartikel (refereegranskat)abstract
- Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is emerging as a tool for studying the metabolism of disease. ToF-SIMS enables chemical specificity in addition to high spatial resolution imaging of biological samples from cells to tissue. Here, ToF-SIMS has been used to investigate the metabolic regulation of hypoxia-induced chemoresistance to doxorubicin treatment using multicellular tumour spheroids. Imaging principal component analysis (PCA) was used as a tool to identify the regions of chemistry present within the image that differ as a result of drug treatment. A series of metabolite ToF-SIMS spectra were acquired, which were used to identify quasi-molecular ions and fragments correlated to the PCA loading plots. Metabolite patterns have been identified as potential biomarkers of hypoxia-induced chemoresistance.
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| 16. |
- Moore, Jimmy D., et al.
(författare)
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Peak picking as a pre-processing technique for imaging time of flight secondary ion mass spectrometry
- 2013
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Ingår i: Surface and Interface Analysis. - 0142-2421 .- 1096-9918. ; 45:1, s. 461-465
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Tidskriftsartikel (refereegranskat)abstract
- High surface sensitivity and lateral resolution imaging make time-of-flight secondary ion mass spectrometry (ToF-SIMS) a unique and powerful tool for biological analysis. However, with the leaps forward made in the capabilities of the ToF-SIMS instrumentation, the data being recorded from these instruments has dramatically increased. Unfortunately, with these large, often complex, datasets, a bottleneck appears in their processing and interpretation. Here, an application of peak picking is described and applied to ToF-SIMS images allowing for large compression of data, noise removal and improved contrast, while retaining a high percentage of the original signal. Peak picking is performed to locate peaks within ToF-SIMS data. By using this information, signal arising from the same distribution can be summed and overlapping signals separated. As a result, the data size and complexity can be dramatically reduced. This method also acts as an effective noise filter, discarding unwanted noise from the data set. Peak picking and separation are evaluated against the conventional methods of mass binning and manually selecting regions of a peak to image on a model data set.
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| 17. |
- Nakano, Shusuke, et al.
(författare)
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Evaluation of biomolecular distributions in rat brain tissues by means of ToF-SIMS using a continuous beam of Ar clusters
- 2016
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Ingår i: Biointerphases. - : American Vacuum Society. - 1559-4106 .- 1934-8630. ; 11:2
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Tidskriftsartikel (refereegranskat)abstract
- Time-of-flight secondary ion mass spectrometry (ToF-SIMS) provides detailed chemical structure information and high spatial resolutionimages. Therefore, ToF-SIMS is useful for studying biological phenomena such as ischemia. In this study, in order to evaluate cerebral microinfarction, the distribution of biomolecules generated by ischemia was measured with ToF-SIMS. ToF-SIMS data sets were analyzed by means of multivariate analysis for interpreting complex samples containing unknown information and to obtain biomolecular mapping indicated by fragment ions from the target biomolecules. Using conventional ToF-SIMS (primary ion source: Bi cluster ion), it is difficult to detect secondary ions beyond approximately 1000 u. Moreover, the intensity of secondary ions related to biomolecules is not always high enough for imaging because of low concentration even if the masses are lower than 1000 u. However, for the observation of biomolecular distributions in tissues, it is important to detect low amounts of biological molecules from a particular area of tissue. Rat braintissue samples were measured with ToF-SIMS (J105, Ionoptika, Ltd., Chandlers Ford, UK), using a continuous beam of Ar clusters as a primary ion source. ToF-SIMS with Ar clusters efficiently detects secondary ions related to biomolecules and larger molecules. Molecules detected by ToF-SIMS were examined by analyzing ToF-SIMS data using multivariate analysis. Microspheres (45μm diameter) were injected into the rat unilateral internal carotid artery (MS rat) to cause cerebral microinfarction. The rat brain was sliced and then measured with ToF-SIMS. The brain samples of a normal rat and the MS rat were examined to find specific secondary ions related to important biomolecules, and then the difference between them was investigated. Finally, specific secondary ions were found around vessels incorporating microspheres in the MS rat. The results suggest that important biomolecules related to cerebral microinfarction can be detected by ToF-SIMS.
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| 18. |
- Sampson, Joshua N., et al.
(författare)
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Analysis of Heritability and Shared Heritability Based on Genome-Wide Association Studies for 13 Cancer Types
- 2015
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press (OUP). - 0027-8874 .- 1460-2105. ; 107:12
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Tidskriftsartikel (refereegranskat)abstract
- Background: Studies of related individuals have consistently demonstrated notable familial aggregation of cancer. We aim to estimate the heritability and genetic correlation attributable to the additive effects of common single-nucleotide polymorphisms (SNPs) for cancer at 13 anatomical sites. Methods: Between 2007 and 2014, the US National Cancer Institute has generated data from genome-wide association studies (GWAS) for 49 492 cancer case patients and 34 131 control patients. We apply novel mixed model methodology (GCTA) to this GWAS data to estimate the heritability of individual cancers, as well as the proportion of heritability attributable to cigarette smoking in smoking-related cancers, and the genetic correlation between pairs of cancers. Results: GWAS heritability was statistically significant at nearly all sites, with the estimates of array-based heritability, h(l)(2), on the liability threshold (LT) scale ranging from 0.05 to 0.38. Estimating the combined heritability of multiple smoking characteristics, we calculate that at least 24% (95% confidence interval [CI] = 14% to 37%) and 7% (95% CI = 4% to 11%) of the heritability for lung and bladder cancer, respectively, can be attributed to genetic determinants of smoking. Most pairs of cancers studied did not show evidence of strong genetic correlation. We found only four pairs of cancers with marginally statistically significant correlations, specifically kidney and testes (rho = 0.73, SE = 0.28), diffuse large B-cell lymphoma (DLBCL) and pediatric osteosarcoma (rho = 0.53, SE = 0.21), DLBCL and chronic lymphocytic leukemia (CLL) (rho = 0.51, SE = 0.18), and bladder and lung (rho = 0.35, SE = 0.14). Correlation analysis also indicates that the genetic architecture of lung cancer differs between a smoking population of European ancestry and a nonsmoking Asian population, allowing for the possibility that the genetic etiology for the same disease can vary by population and environmental exposures. Conclusion: Our results provide important insights into the genetic architecture of cancers and suggest new avenues for investigation.
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| 19. |
- Schrijver, Lieske H, et al.
(författare)
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Oral contraceptive use and ovarian cancer risk for BRCA1/2 mutation carriers : an international cohort study
- 2021
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Ingår i: American Journal of Obstetrics and Gynecology. - : Elsevier BV. - 1097-6868 .- 0002-9378. ; 225:1, s. 1-51
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Ovarian cancer risk in BRCA1 and BRCA2 mutation carriers has been shown to decrease with longer duration of oral contraceptive preparations (OCPs) use. While the effects of OCPs in the general population are well established (∼50% reduction), the estimated risk reduction in mutation carriers is much less precise due to potential bias and small sample sizes. In addition, only a few studies have examined the associations between duration of use, time since last use, starting age, and calendar year of start with risk of ovarian cancer.OBJECTIVE(S): To investigate in more detail the associations between various characteristics of OCP use and risk of ovarian cancer, to provide health care providers and carriers with better risk estimates.STUDY DESIGN: In this international retrospective study, ovarian cancer risk associations were assessed using OCP data on 3,989 BRCA1 and 2,445 BRCA2 mutation carriers. Age-dependent weighted Cox regression analyses were stratified by study and birth cohort and included breast cancer diagnosis as covariate. To minimize survival bias, analyses were left-truncated at 5 years before baseline questionnaire. Separate analysis were conducted for each of the aspects of OCP use and in a multivariate analysis including all these aspects. In addition, the analysis of duration of OCP use was stratified by recency of use.RESULTS: OCPs were less often used by mutation carriers who were diagnosed with ovarian cancer (Ever use: BRCA1 58.6%, BRCA2 53.5%) than by unaffected carriers (Ever use: BRCA1 88.9%, BRCA2 80.7%. The median duration of use was 7 years for both BRCA1 and BRCA2 carriers who developed ovarian cancer, and 9 and 8 years for ovarian cancer unaffected BRCA1 and BRCA2 carriers, respectively. For BRCA1 mutation carriers univariate analyses showed that both a longer duration of OCP use and more recent use of OCPs were inversely associated with risk of ovarian cancer. However, in multivariate analyses including duration of use, age at first use and time since last use, duration of use proved to be the prominent protective factor (compared with <5 years, 5-9 years HR=0.67;95%CI 0.40-1.12, 10+ years HR=0.37;95%CI 0.19-0.73; ptrend=0.008). The inverse association between duration of use and ovarian cancer risk persisted for more than 15 years (Duration of ≥10 years; BRCA1: <15 years since last use: HR=0.24 95%CI 0.14-0.43, 15+ years since last use: HR 0.56 95%CI 0.18-0.59). Univariate results for BRCA2 mutation carriers were similar, but due to limit sample size inconclusive.CONCLUSION: For BRCA1 mutation carriers, a longer duration of OCP use is associated with a greater reduction of ovarian cancer risk and the protection is long term.
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| 20. |
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| 21. |
- Tian, Hua, et al.
(författare)
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Spatiotemporal lipid profiling during early embryo development of Xenopus laevis using dynamic Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) Imaging
- 2014
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Ingår i: Journal of Lipid Research. - 0022-2275 .- 1539-7262. ; Epub ahead of print
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Tidskriftsartikel (refereegranskat)abstract
- Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) imaging has been used for the direct analysis of single intact Xenopus laevis (X. laevis) embryo surfaces, locating multiple lipids during fertilisation and the early embryo development stages with sub-cellular lateral resolution (~4 Microns). The method avoids the complicated sample preparation for lipid analysis of the embryos, which requires selective chemical extraction of a pool of samples and chromatographic separation, while preserving the spatial distribution of biological species. The results show ToF-SIMS is capable of profiling multiple components (e.g., glycerophosphocholine, sphingomyelin, cholesterol, vitamin E, diacylglycerol, triacylglycerol) in a single X. laevis embryo. We observe lipid remodelling during fertilisation and early embryo development via time course sampling. The study also reveals the lipid distribution on the gametes fusion site. The methodology used in the study opens the possibility of studying developmental biology using high resolution imaging MS and of understanding the functional role of the biological molecules.
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| 22. |
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| 23. |
- Vaidyanathan, Seetharaman, et al.
(författare)
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Exploratory analysis of TOF-SIMS data from biological surfaces
- 2008
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Ingår i: Applied Surface Science. - : Elsevier BV. - 0169-4332. ; 255:4, s. 1599-1602
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Konferensbidrag (refereegranskat)abstract
- The application of multivariate analytical tools enables simplification of TOF-SIMS datasets so that useful information can be extracted from complex spectra and images, especially those that do not give readily interpretable results. There is however a challenge in understanding the outputs from such analyses. The problem is complicated when analysing images, given the additional dimensions in the dataset. Here we demonstrate how the application of simple pre-processing routines can enable the interpretation of TOF-SIMS spectra and images. For the spectral data, TOF-SIMS spectra used to discriminate bacterial isolates associated with urinary tract infection were studied. Using different criteria for picking peaks before carrying out PC-DFA enabled identification of the discriminatory information with greater certainty. For the image data, an air-dried salt stressed bacterial sample, discussed in another paper by us in this issue, was studied. Exploration of the image datasets with and without normalisation prior to multivariate analysis by PCA or MAF resulted in different regions of the image being highlighted by the techniques. (C) 2008 Elsevier B. V. All rights reserved.
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| 24. |
- Aad, G., et al.
(författare)
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- 2012
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swepub:Mat__t (refereegranskat)
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| 25. |
- Niemi, MEK, et al.
(författare)
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- 2021
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swepub:Mat__t
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