Journal articles: 'XFM'

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Maric, Vesna D., Marija M. Bozic, Andja M. Cirkovic, Sanja Dj Stankovic, Ivan S. Marjanovic, and Anita D. Grgurevic. "Serum heparan sulfate and chondroitin sulfate concentrations in patients with newly diagnosed exfoliative glaucoma." PeerJ 7 (May 23, 2019): e6920. http://dx.doi.org/10.7717/peerj.6920.

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Background Exfoliative glaucoma (XFG) is typically classified as a high-pressure type of secondary open-angle glaucoma that develops as a consequence of exfoliation syndrome (XFS). Exfoliation syndrome is an age-related, generalized disorder of the extracellular matrix characterized by production and progressive accumulation of a fibrillar exfoliation material (XFM) in intra- and extraocular tissues. Exfoliation material represents complex glycoprotein/proteoglycan structure composed of a protein core surrounded by glycosaminoglycans such as heparan sulfate (HS) and chondroitin sulfate (CS). The purpose of the present study was to investigate HS and CS concentrations in serum samples of patients with newly diagnosed XFG and compare the obtained values with those pertaining to newly diagnosed primary open-angle glaucoma (POAG), normal controls (NC) and subjects with XFS. Methods This case–control study involved 165 subjects, including patients with newly diagnosed XFG, patients with newly diagnosed POAG, subjects with XFS and age- and sex-matched NC. The study was conducted at the Glaucoma Department of Clinic for Eye Diseases, Clinical Centre of Serbia, as the referral center for glaucoma in Serbia. Results The mean age in the XFG, POAG, XFS and NC groups was 73.3 ± 9.0, 66.3 ± 7.8, 75.5 ± 7.0 and 73.5 ± 9.5 years, respectively, XFG vs. POAG, p < 0.001. Mean serum HS concentrations in the XFG, POAG, NC and XFS groups were 3,189.0 ± 1,473.8 ng/mL, 2,091.5 ± 940.9 ng/mL, 2,543.1 ± 1,397.3 ng/mL and 2,658.2 ± 1,426.8 ng/mL respectively, XFG vs. POAG, p = 0.001 and XFG vs. NC, p = 0.032. Mean serum CS concentrations in the XFG, POAG, NC and XFS group were 43.9 ± 20.7 ng/mL, 38.5 ± 22.0 ng/mL, 35.8 ± 16.4 ng/mL and 43.3 ± 21.8 ng/mL, respectively, XFG vs. NC, p = 0.041. Conclusions Our findings revealed greater HS and CS concentrations in XFG patients and XFS subjects compared to those without XFM. Implications of HS and CS in the pathophysiology of XFS and glaucoma should be studied further. Serum is easily accessible and should thus be explored as rich sources of potential biomarkers. Further research should aim to identify XFG biomarkers that could be utilized in routine blood analysis tests, aiding in timely disease diagnosis.

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Di Genova, Dario, Kippy J. Lewis, and Jonathan E. Oliver. "Natural Infection of Southern Highbush Blueberry (Vaccinium corymbosum Interspecific Hybrids) by Xylella fastidiosa subsp. fastidiosa." Plant Disease 104, no. 10 (October 2020): 2598–605. http://dx.doi.org/10.1094/pdis-11-19-2477-re.

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Xylella fastidiosa (Xf) is an emerging insect-vectored, xylem-limited bacterium that can cause disease on several economically important fruit and tree crops including almond, blueberry, citrus, grapevine, peach, and pecan. On blueberry, Xf causes bacterial leaf scorch (BLS), which is prevalent in the southeastern United States. This disease, previously reported to be caused by Xf subsp. multiplex (Xfm), can result in rapid plant decline and death of southern highbush (SHB) blueberry cultivars. In 2017, a survey of blueberry plantings in southern Georgia (U.S.A.) confirmed the presence of Xf-infected plants in eight of nine sites examined, and seven isolates were cultured from infected plants. Genetic characterization of these isolates through single-locus and multilocus sequence analysis revealed that three isolates from two sites belonged to Xf subsp. fastidiosa (Xff), with significant similarity to isolates from grapevine. After these three isolates were artificially inoculated onto greenhouse-grown SHB blueberries (cv. ‘Rebel’), symptoms typical of BLS developed, and Xff infection was confirmed through genetic characterization and reisolation of the bacterium to fulfill Koch’s postulates. Because all previously reported Xf isolates from blueberry have been characterized as Xfm, this is the first time that isolation of Xff has been reported from naturally infected blueberry plantings. The potential impact of Xff isolates on disease management in blueberry requires further exploration. Furthermore, given that isolates from both Xfm and Xff were obtained within a single naturally infected blueberry planting, blueberry in southern Georgia may provide opportunities for intersubspecific recombination between Xff and Xfm isolates.

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Suhaib, Syed M., Deepak A. Mathaikutty, Sandeep K. Shukla, and David Berner. "XFM." ACM Transactions on Design Automation of Electronic Systems 10, no. 4 (October 2005): 589–609. http://dx.doi.org/10.1145/1109118.1109120.

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Yue, Xi Qing, Xin Li, Jun Rui Wu, and Miao Zhang. "Isolation and Identification of Lactobacillus from Naturally Fermented Sauerkraut Juices in Xifeng." Advanced Materials Research 726-731 (August 2013): 147–50. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.147.

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Four suspected Lactobacillus strains (XF1,XF2.XF3 and XF4) were isolated from one naturally fermented sauerkraut juice collected from Xifeng,Liaoning Province. By gram staining and catalase activity experiments,Two strains (XF1 and XF4) were retained.The strains were identified by 16S rDNA sequence analysis.The results showed that XF1 and XF4 were both identified as Lactobacillus curvatus.

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Ma, Ning, Xin Li, Hong-bin Wang, Li Gao, and Jian-hua Xiao. "Effects of tiletamine-xylazine-tramadol combination and its specific antagonist on AMPK in the brain of rats." Journal of Veterinary Research 63, no. 2 (June 1, 2019): 285–92. http://dx.doi.org/10.2478/jvetres-2019-0027.

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AbstractIntroduction:Tiletamine-xylazine-tramadol (XFM) has few side effects and can provide good sedation and analgesia. Adenosine 5’-monophosphate-activated protein kinase (AMPK) can attenuate trigeminal neuralgia. The study aimed to investigate the effects of XFM and its specific antagonist on AMPK in different regions of the brain.Material and Methods:A model of XFM in the rat was established. A total of 72 Sprague Dawley (SD) rats were randomly divided into three equally sized groups: XFM anaesthesia (M group), antagonist (W group), and XFM with antagonist interactive groups (MW group). Eighteen SD rats were in the control group and were injected intraperitoneally with saline (C group). The rats were sacrificed and the cerebral cortex, cerebellum, hippocampus, thalamus, and brain stem were immediately separated, in order to detect AMPKα mRNA expression by quantitative PCR.Results:XFM was able to increase the mRNA expression of AMPKα1 and AMPKα2 in all brain regions, and the antagonist caused the opposite effect, although the effects of XFM could not be completely reversed in some areas.Conclusion:XFM can influence the expression of AMPK in the central nervous system of the rat, which can provide a reference for the future development of anaesthetics for animals.

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Jones, Michael W. M., Peter M. Kopittke, Lachlan Casey, Juliane Reinhardt, F. Pax C. Blamey, and Antony van der Ent. "Assessing radiation dose limits for X-ray fluorescence microscopy analysis of plant specimens." Annals of Botany 125, no. 4 (November 28, 2019): 599–610. http://dx.doi.org/10.1093/aob/mcz195.

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Abstract Background and Aims X-ray fluorescence microscopy (XFM) is a powerful technique to elucidate the distribution of elements within plants. However, accumulated radiation exposure during analysis can lead to structural damage and experimental artefacts including elemental redistribution. To date, acceptable dose limits have not been systematically established for hydrated plant specimens. Methods Here we systematically explore acceptable dose rate limits for investigating fresh sunflower (Helianthus annuus) leaf and root samples and investigate the time–dose damage in leaves attached to live plants. Key Results We find that dose limits in fresh roots and leaves are comparatively low (4.1 kGy), based on localized disintegration of structures and element-specific redistribution. In contrast, frozen-hydrated samples did not incur any apparent damage even at doses as high as 587 kGy. Furthermore, we find that for living plants subjected to XFM measurement in vivo and grown for a further 9 d before being reimaged with XFM, the leaves display elemental redistribution at doses as low as 0.9 kGy and they continue to develop bleaching and necrosis in the days after exposure. Conclusions The suggested radiation dose limits for studies using XFM to examine plants are important for the increasing number of plant scientists undertaking multidimensional measurements such as tomography and repeated imaging using XFM.

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Jones, Michael W. M., Nicholas W. Phillips, Grant A. van Riessen, Brian Abbey, David J. Vine, Youssef S. G. Nashed, Stephen T. Mudie, et al. "Simultaneous X-ray fluorescence and scanning X-ray diffraction microscopy at the Australian Synchrotron XFM beamline." Journal of Synchrotron Radiation 23, no. 5 (August 11, 2016): 1151–57. http://dx.doi.org/10.1107/s1600577516011917.

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Owing to its extreme sensitivity, quantitative mapping of elemental distributionsviaX-ray fluorescence microscopy (XFM) has become a key microanalytical technique. The recent realisation of scanning X-ray diffraction microscopy (SXDM) meanwhile provides an avenue for quantitative super-resolved ultra-structural visualization. The similarity of their experimental geometries indicates excellent prospects for simultaneous acquisition. Here, in both step- and fly-scanning modes, robust, simultaneous XFM-SXDM is demonstrated.

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Naim, Fatima, Karina Khambatta, Lilian M. V. P. Sanglard, Georgina Sauzier, Juliane Reinhardt, David J. Paterson, Ayalsew Zerihun, Mark J. Hackett, and Mark R. Gibberd. "Synchrotron X-ray fluorescence microscopy-enabled elemental mapping illuminates the ‘battle for nutrients’ between plant and pathogen." Journal of Experimental Botany 72, no. 7 (January 13, 2021): 2757–68. http://dx.doi.org/10.1093/jxb/erab005.

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Abstract Metal homeostasis is integral to normal plant growth and development. During plant–pathogen interactions, the host and pathogen compete for the same nutrients, potentially impacting nutritional homeostasis. Our knowledge of outcome of the interaction in terms of metal homeostasis is still limited. Here, we employed the X-ray fluorescence microscopy (XFM) beamline at the Australian Synchrotron to visualize and analyse the fate of nutrients in wheat leaves infected with Pyrenophora tritici-repentis, a necrotrophic fungal pathogen. We sought to (i) evaluate the utility of XFM for sub-micron mapping of essential mineral nutrients and (ii) examine the spatiotemporal impact of a pathogen on nutrient distribution in leaves. XFM maps of K, Ca, Fe, Cu, Mn, and Zn revealed substantial hyperaccumulation within, and depletion around, the infected region relative to uninfected control samples. Fungal mycelia were visualized as thread-like structures in the Cu and Zn maps. The hyperaccumulation of Mn in the lesion and localized depletion in asymptomatic tissue surrounding the lesion was unexpected. Similarly, Ca accumulated at the periphery of the symptomatic region and as microaccumulations aligning with fungal mycelia. Collectively, our results highlight that XFM imaging provides the capability for high-resolution mapping of elements to probe nutrient distribution in hydrated diseased leaves in situ.

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Waliullah, Sumyya, Dario Di Genova, Jonathan E. Oliver, and Md Emran Ali. "Development of a CAPS Marker and a LAMP Assay for Rapid Detection of Xylella fastidiosa Subsp. multiplex and Differentiation from X. fastidiosa Subsp. fastidiosa on Blueberry." International Journal of Molecular Sciences 23, no. 4 (February 9, 2022): 1937. http://dx.doi.org/10.3390/ijms23041937.

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Bacterial leaf scorch (BLS), caused by Xylella fastidiosa (Xf), is a prevalent disease of blueberries in the southeastern United States. Initially, this disease was reported to be caused by X. fastidiosa subsp. multiplex (Xfm). However, a recent survey revealed the presence of another subspecies, X. fastidiosa subsp. fastidiosa (Xff), within naturally infected blueberry plantings in Georgia. Since knowledge regarding the origins of isolates causing Xf outbreaks can impact management recommendations, a routine method for identifying the pathogen at the subspecies level can be beneficial. Several detection strategies are available to identify Xf infection at the subspecies level. However, none of these have been developed for the routine and rapid differentiation of the blueberry-infecting Xf subspecies. Here, we developed two separate straightforward and rapid detection techniques, a cleaved amplified polymorphic sequence (CAPS) marker, and a loop-mediated isothermal amplification (LAMP) assay, targeting the RNA polymerase sigma-70 factor (rpoD) gene sequence of Xfm to discriminate between the two Xf subspecies infecting blueberry. With the CAPS marker, specific detection of Xfm isolates was possible from pure cultures, inoculated greenhouse-grown plant samples, and field infected blueberry samples by restriction digestion of the rpoD gene PCR product (amplified with primers RST31 and RST33) using the BtsI enzyme. The LAMP assay allowed for specific real-time amplification of a 204-bp portion of the XfmrpoD gene from both pure bacterial cultures and infected plant material using the Genie® III system, a result further affirmed by gel electrophoresis and SYBR™ Green I DNA staining for visual observation. These detection strategies have the potential to greatly aid existing diagnostic methods for determining the distribution and prevalence of these Xf subspecies causing bacterial leaf scorch (BLS) in blueberries in the southeastern United States.

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Schmollinger, Stefan, Si Chen, Daniela Strenkert, Colleen Hui, Martina Ralle, and Sabeeha S. Merchant. "Single-cell visualization and quantification of trace metals in Chlamydomonas lysosome-related organelles." Proceedings of the National Academy of Sciences 118, no. 16 (April 16, 2021): e2026811118. http://dx.doi.org/10.1073/pnas.2026811118.

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The acidocalcisome is an acidic organelle in the cytosol of eukaryotes, defined by its low pH and high calcium and polyphosphate content. It is visualized as an electron-dense object by transmission electron microscopy (TEM) or described with mass spectrometry (MS)–based imaging techniques or multimodal X-ray fluorescence microscopy (XFM) based on its unique elemental composition. Compared with MS-based imaging techniques, XFM offers the additional advantage of absolute quantification of trace metal content, since sectioning of the cell is not required and metabolic states can be preserved rapidly by either vitrification or chemical fixation. We employed XFM in Chlamydomonas reinhardtii to determine single-cell and organelle trace metal quotas within algal cells in situations of trace metal overaccumulation (Fe and Cu). We found up to 70% of the cellular Cu and 80% of Fe sequestered in acidocalcisomes in these conditions and identified two distinct populations of acidocalcisomes, defined by their unique trace elemental makeup. We utilized the vtc1 mutant, defective in polyphosphate synthesis and failing to accumulate Ca, to show that Fe sequestration is not dependent on either. Finally, quantitation of the Fe and Cu contents of individual cells and compartments via XFM, over a range of cellular metal quotas created by nutritional and genetic perturbations, indicated excellent correlation with bulk data from corresponding cell cultures, establishing a framework to distinguish the nutritional status of single cells.

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Genoud, Sian, Michael W. M. Jones, Benjamin Guy Trist, Junjing Deng, Si Chen, Dominic James Hare, and Kay L. Double. "Simultaneous structural and elemental nano-imaging of human brain tissue." Chemical Science 11, no. 33 (2020): 8919–27. http://dx.doi.org/10.1039/d0sc02844d.

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Grubman, A., S. A. James, J. James, C. Duncan, I. Volitakis, J. L. Hickey, P. J. Crouch, et al. "X-ray fluorescence imaging reveals subcellular biometal disturbances in a childhood neurodegenerative disorder." Chem. Sci. 5, no. 6 (2014): 2503–16. http://dx.doi.org/10.1039/c4sc00316k.

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Luan, Bao, Timo Friedrich, Jiali Zhai, Victor A. Streltsov, Benjamin W. Lindsey, Jan Kaslin, Martin D. de Jonge, Jin Zhu, Timothy C. Hughes, and Xiaojuan Hao. "A library of AuNPs modified by RAFT polymers of different charge and chain length: high throughput synthesis and synchrotron XFM imaging using a zebrafish larvae model." RSC Advances 6, no. 28 (2016): 23550–63. http://dx.doi.org/10.1039/c6ra02801b.

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Howard, Daryl L., Martin D. de Jonge, Nader Afshar, Chris G. Ryan, Robin Kirkham, Juliane Reinhardt, Cameron M. Kewish, et al. "The XFM beamline at the Australian Synchrotron." Journal of Synchrotron Radiation 27, no. 5 (August 19, 2020): 1447–58. http://dx.doi.org/10.1107/s1600577520010152.

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The X-ray fluorescence microscopy (XFM) beamline is an in-vacuum undulator-based X-ray fluorescence (XRF) microprobe beamline at the 3 GeV Australian Synchrotron. The beamline delivers hard X-rays in the 4–27 keV energy range, permitting K emission to Cd and L and M emission for all other heavier elements. With a practical low-energy detection cut-off of approximately 1.5 keV, low-Z detection is constrained to Si, with Al detectable under favourable circumstances. The beamline has two scanning stations: a Kirkpatrick–Baez mirror microprobe, which produces a focal spot of 2 µm × 2 µm FWHM, and a large-area scanning `milliprobe', which has the beam size defined by slits. Energy-dispersive detector systems include the Maia 384, Vortex-EM and Vortex-ME3 for XRF measurement, and the EIGER2 X 1 Mpixel array detector for scanning X-ray diffraction microscopy measurements. The beamline uses event-mode data acquisition that eliminates detector system time overheads, and motion control overheads are significantly reduced through the application of an efficient raster scanning algorithm. The minimal overheads, in conjunction with short dwell times per pixel, have allowed XFM to establish techniques such as full spectroscopic XANES fluorescence imaging, XRF tomography, fly scanning ptychography and high-definition XRF imaging over large areas. XFM provides diverse analysis capabilities in the fields of medicine, biology, geology, materials science and cultural heritage. This paper discusses the beamline status, scientific showcases and future upgrades.

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Chen, Si, Ruben Omar Lastra, Tatjana Paunesku, Olga Antipova, Luxi Li, Junjing Deng, Yanqi Luo, et al. "Development of Multi-Scale X-ray Fluorescence Tomography for Examination of Nanocomposite-Treated Biological Samples." Cancers 13, no. 17 (September 6, 2021): 4497. http://dx.doi.org/10.3390/cancers13174497.

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Research in cancer nanotechnology is entering its third decade, and the need to study interactions between nanomaterials and cells remains urgent. Heterogeneity of nanoparticle uptake by different cells and subcellular compartments represent the greatest obstacles to a full understanding of the entire spectrum of nanomaterials’ effects. In this work, we used flow cytometry to evaluate changes in cell cycle associated with non-targeted nanocomposite uptake by individual cells and cell populations. Analogous single cell and cell population changes in nanocomposite uptake were explored by X-ray fluorescence microscopy (XFM). Very few nanoparticles are visible by optical imaging without labeling, but labeling increases nanoparticle complexity and the risk of modified cellular uptake. XFM can be used to evaluate heterogeneity of nanocomposite uptake by directly imaging the metal atoms present in the metal-oxide nanocomposites under investigation. While XFM mapping has been performed iteratively in 2D with the same sample at different resolutions, this study is the first example of serial tomographic imaging at two different resolutions. A cluster of cells exposed to non-targeted nanocomposites was imaged with a micron-sized beam in 3D. Next, the sample was sectioned for immunohistochemistry as well as a high resolution “zoomed in” X-ray fluorescence (XRF) tomography with 80 nm beam spot size. Multiscale XRF tomography will revolutionize our ability to explore cell-to-cell differences in nanomaterial uptake.

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Ciccotosto, Giuseppe D., Simon A. James, Matteo Altissimo, David Paterson, Stefan Vogt, Barry Lai, Martin D. de Jonge, Daryl L. Howard, Ashley I. Bush, and Roberto Cappai. "Quantitation and localization of intracellular redox active metals by X-ray fluorescence microscopy in cortical neurons derived from APP and APLP2 knockout tissue." Metallomics 6, no. 10 (2014): 1894–904. http://dx.doi.org/10.1039/c4mt00176a.

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The intracellular metal concentration and distribution for Cu, Zn, Fe and Ca were determined by X-ray fluorescence microscopy (XFM) in cultured cortical neurons and were found to be altered in mice lacking APP and APLP2 expression.

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Doolette, Casey L., Daryl L. Howard, Nader Afshar, Cameron M. Kewish, David J. Paterson, Jianyin Huang, Stefan Wagner, et al. "Tandem Probe Analysis Mode for Synchrotron XFM: Doubling Throughput Capacity." Analytical Chemistry 94, no. 11 (March 11, 2022): 4584–93. http://dx.doi.org/10.1021/acs.analchem.1c04255.

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Clavijo-Coppens, Fernando, Nicolas Ginet, Sophie Cesbron, Martial Briand, Marie-Agnès Jacques, and Mireille Ansaldi. "Novel Virulent Bacteriophages Infecting Mediterranean Isolates of the Plant Pest Xylella fastidiosa and Xanthomonas albilineans." Viruses 13, no. 5 (April 21, 2021): 725. http://dx.doi.org/10.3390/v13050725.

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Xylella fastidiosa (Xf) is a plant pathogen causing significant losses in agriculture worldwide. Originating from America, this bacterium caused recent epidemics in southern Europe and is thus considered an emerging pathogen. As the European regulations do not authorize antibiotic treatment in plants, alternative treatments are urgently needed to control the spread of the pathogen and eventually to cure infected crops. One such alternative is the use of phage therapy, developed more than 100 years ago to cure human dysentery and nowadays adapted to agriculture. The first step towards phage therapy is the isolation of the appropriate bacteriophages. With this goal, we searched for phages able to infect Xf strains that are endemic in the Mediterranean area. However, as Xf is truly a fastidious organism, we chose the phylogenetically closest and relatively fast-growing organism X. albineans as a surrogate host for the isolation step. Our results showed the isolation from various sources and preliminary characterization of several phages active on different Xf strains, namely, from the fastidiosa (Xff), multiplex (Xfm), and pauca (Xfp) subspecies, as well as on X. albilineans. We sequenced their genomes, described their genomic features, and provided a phylogeny analysis that allowed us to propose new taxonomic elements. Among the 14 genomes sequenced, we could identify two new phage species, belonging to two new genera of the Caudoviricetes order, namely, Usmevirus (Podoviridae family) and Subavirus (Siphoviridae family). Interestingly, no specific phages could be isolated from infected plant samples, whereas one was isolated from vector insects captured in a contaminated area, and several from surface and sewage waters from the Marseille area.

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Barnes, Stephen J., David Paterson, Teresa Ubide, Louise E. Schoneveld, Chris Ryan, and Margaux Le Vaillant. "Imaging trace-element zoning in pyroxenes using synchrotron XRF mapping with the Maia detector array: Benefit of low-incident energy." American Mineralogist 105, no. 1 (January 1, 2020): 136–40. http://dx.doi.org/10.2138/am-2020-7228.

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Abstract Trace-element zoning in igneous phenocrysts and cumulus phases is an informative record of magmatic evolution. The advent of microbeam X-ray fluorescence (XRF) mapping has allowed rapid chemical imaging of samples at thin section to decimeter scale, revealing such zoning patterns. Mapping with synchrotron radiation using multidetector arrays has proved especially effective, allowing entire thin sections to be imaged at micrometer-scale resolution in a matter of hours. The resolution of subtle minor element zoning, particularly in first-row transition metals, is greatly enhanced in synchrotron X-ray fluorescence microscopy (XFM) images by scanning with input beam energy below the FeKα line. In the examples shown here, from a phenocryst rich trachybasalt from Mt Etna (Italy) and from a Ni-Cu-PGE ore-bearing intrusion at Norilsk (Siberia), the zoning patterns revealed in this way record aspects of the crystallization history that are not readily evident from XFM images collected using higher incident energies and that cannot be obtained at comparable spatial resolutions by any other methods within reasonable scan times. This approach has considerable potential as a geochemical tool for investigating magmatic processes and is also likely to be applicable in a wide variety of other fields.

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Ganshina, Elena Alexandrovna, Vladimir Valentinovich Garshin, Ilya Mikhailovich Pripechenkov, Sergey Alexandrovich Ivkov, Alexander Victorovich Sitnikov, and Evelina Pavlovna Domashevskaya. "Effect of Phase Transformations of a Metal Component on the Magneto-Optical Properties of Thin-Films Nanocomposites (CoFeZr)x (MgF2)100−x." Nanomaterials 11, no. 7 (June 24, 2021): 1666. http://dx.doi.org/10.3390/nano11071666.

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The results of complex studies of structural-phase transformations and magneto-optical properties of nanocomposites (CoFeZr)x (MgF2)100−x depending on the metal alloy content in the dielectric matrix are presented. Nanocomposites were deposited by ion-beam sputtering onto glass and glass-ceramic substrate. By studying the spectral and field dependences of the transversal Kerr effect (TKE), it was found that the transition of nanocomposites from superparamagnetic to the ferromagnetic state occurs in the region of xfm~30 at%, that corresponds to the onset the formation of ferromagnetic nanocrystals CoFeZr with hexagonal syngony in amorphous dielectric matrix of MgF2. With an increase of concentrations of the metal alloy for x > xfm, the features associated with structural transitions in magnetic granules are revealed in the TKE spectra. Comparison of the spectral and concentration dependences of TKE for nanocomposites on the glass and glass-ceramics substrates showed that the strongest differences occur in the region of the phase structural transition of CoFeZr nanocrystals from a hexagonal to a body-centered cubic structure at x = 38 at.% on the glass substrates and at x = 46 at.% on glass-ceramics substrates, due to different diffusion rates and different size of metal nanocrystals on amorphous glass substrates and more rough polycrystalline glass-ceramics substrates.

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Pascolo, Lorella, Alessandra Gianoncelli, Clara Rizzardi, Martin de Jonge, Daryl Howard, David Paterson, Francesca Cammisuli, et al. "Focused X-Ray Histological Analyses to Reveal Asbestos Fibers and Bodies in Lungs and Pleura of Asbestos-Exposed Subjects." Microscopy and Microanalysis 22, no. 5 (September 13, 2016): 1062–71. http://dx.doi.org/10.1017/s1431927616011685.

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AbstractAsbestos bodies are the histological hallmarks of asbestos exposure. Both conventional and advanced techniques are used to evaluate abundance and composition in histological samples. We previously reported the possibility of using synchrotron X-ray fluorescence microscopy (XFM) for analyzing the chemical composition of asbestos bodies directly in lung tissue samples. Here we applied a high-performance synchrotron X-ray fluorescence (XRF) set-up that could allow new protocols for fast monitoring of the occurrence of asbestos bodies in large histological sections, improving investigation of the related chemical changes. A combination of synchrotron X-ray transmission and fluorescence microscopy techniques at different energies at three distinct synchrotrons was used to characterize asbestos in paraffinated lung tissues. The fast chemical imaging of the XFM beamline (Australian Synchrotron) demonstrates that asbestos bodies can be rapidly and efficiently identified as co-localization of high calcium and iron, the most abundant elements of these formations inside tissues (Fe up to 10% w/w; Ca up to 1%). By following iron presence, we were also able to hint at small asbestos fibers in pleural spaces. XRF at lower energy and at higher spatial resolution was afterwards performed to better define small fibers. These analyses may predispose for future protocols to be set with laboratory instruments.

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de Silva, Ranil, Luis F. Gutiérrez, Amish N. Raval, Elliot R. McVeigh, Cengizhan Ozturk, and Robert J. Lederman. "X-Ray Fused With Magnetic Resonance Imaging (XFM) to Target Endomyocardial Injections." Circulation 114, no. 22 (November 28, 2006): 2342–50. http://dx.doi.org/10.1161/circulationaha.105.598524.

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Liu, Shi Qian, Dong Dong Qu, Stuart D. McDonald, and Kazuhiro Nogita. "The Interaction of Sn-Ga Alloys and Au Coated Cu Substrates." Solid State Phenomena 273 (April 2018): 3–8. http://dx.doi.org/10.4028/www.scientific.net/ssp.273.3.

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Ga and Ga-based alloys appear to be promising materials for low temperature soldering in microelectronics. This research involved an analysis of the joint interfaces that resulted from reactions between a eutectic Ga-Sn alloy and Au coated Cu substrates at both room temperature and 100°C. At both temperatures the intermetallic CuGa2 accounted for the majority of the interfacial microstructure. This study has shown the possibility of using eutectic Ga-Sn alloys in low temperature soldering applications, as well as the advantages of Synchrotron XFM techniques in characterising trace element distributions in solder joints.

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Paul, Adrian L. D., Vidiro Gei, Sandrine Isnard, Bruno Fogliani, Guillaume Echevarria, Peter D. Erskine, Tanguy Jaffré, Jérôme Munzinger, and Antony van der Ent. "Nickel hyperaccumulation in New Caledonian Hybanthus (Violaceae) and occurrence of nickel-rich phloem in Hybanthus austrocaledonicus." Annals of Botany 126, no. 5 (June 24, 2020): 905–14. http://dx.doi.org/10.1093/aob/mcaa112.

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Abstract Background and Aims Hybanthus austrocaledonicus (Violaceae) is a nickel (Ni) hyperaccumulator endemic to New Caledonia. One of the specimens stored at the local herbarium had a strip of bark with a remarkably green phloem tissue attached to the sheet containing over 4 wt% Ni. This study aimed to collect field samples from the original H. austrocaledonicus locality to confirm the nature of the green ‘nickel-rich phloem’ in this taxon and to systematically assess the occurrence of Ni hyperaccumulation in H. austrocaledonicus and Hybanthus caledonicus populations. Methods X-ray fluorescence spectroscopy scanning of all collections of the genus Hybanthus (236 specimens) was undertaken at the Herbarium of New Caledonia to reveal incidences of Ni accumulation in populations of H. austrocaledonicus and H. caledonicus. In parallel, micro-analytical investigations were performed via synchrotron X-ray fluorescence microscopy (XFM) and scanning electron microscopy with X-ray microanalysis (SEM-EDS). Key Results The extensive scanning demonstrated that Ni hyperaccumulation is not a characteristic common to all populations in the endemic Hybanthus species. Synchrotron XFM revealed that Ni was exclusively concentrated in the epidermal cells of the leaf blade and petiole, conforming with the majority of (tropical) Ni hyperaccumulator plants studied to date. SEM-EDS of freeze-dried and frozen-hydrated samples revealed the presence of dense solid deposits in the phloem bundles that contained >8 wt% nickel. Conclusions The occurrence of extremely Ni-rich green phloem tissues appears to be a characteristic feature of tropical Ni hyperaccumulator plants.

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Naghi, Monia, Siraj Uddin, and Falleh Al-Solamy. "Warped product submanifolds of Kenmotsu manifolds with slant fiber." Filomat 32, no. 6 (2018): 2115–26. http://dx.doi.org/10.2298/fil1806115n.

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Recently, wehave discussed the warped product pseudo-slant submanifolds of the typeM?xfM? of Kenmotsu manifolds. In this paper, we study other type of warped product pseudo-slant submanifolds by reversing these two factors in Kenmotsu manifolds. The existence of such warped product immersions is proved by a characterization. Also, we provide an example of warped product pseudo-slant submanifolds. Finally, we establish a sharp estimation such as ||h||2?2pcos2?(||??(ln f)||2-1) for the squared norm of the second fundamental form khk2, in terms of the warping function f, where ??(ln f) is the gradient vector of the function ln f. The equality case is also discussed.

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Lehtolainen, A., J. Huovelin, S. Korpela, E. Kilpua, H. Andersson, D. Giurisato, J. Lehti, et al. "SUNSTORM 1/X-ray Flux Monitor for CubeSats (XFM-CS): Instrument characterization and first results." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 1035 (July 2022): 166865. http://dx.doi.org/10.1016/j.nima.2022.166865.

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McCutcheon, Jenine, Luke D. Nothdurft, Gregory E. Webb, Jeremiah Shuster, Linda Nothdurft, David Paterson, and Gordon Southam. "Building biogenic beachrock: Visualizing microbially-mediated carbonate cement precipitation using XFM and a strontium tracer." Chemical Geology 465 (August 2017): 21–34. http://dx.doi.org/10.1016/j.chemgeo.2017.05.019.

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Cumberland, Susan A., Katy Evans, Grant Douglas, Martin de Jonge, Louise Fisher, Daryl Howard, and John W. Moreau. "Characterisation of uranium-pyrite associations within organic-rich Eocene sediments using EM, XFM-µXANES and µXRD." Ore Geology Reviews 133 (June 2021): 104051. http://dx.doi.org/10.1016/j.oregeorev.2021.104051.

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Ticchi, G., M. Venturelli, G. Utica, M. Carminati, G. Borghi, N. Zorzi, G. Falkenberg, and C. Fiorini. "Optimization of Solid Angle and Count Rate Capability of an X-ray Detector with Backscattering Geometry." Journal of Physics: Conference Series 2380, no. 1 (December 1, 2022): 012099. http://dx.doi.org/10.1088/1742-6596/2380/1/012099.

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Abstract We study here an optimized geometry for an X-ray detector with hole in the center, as key component for ASCANIO: an innovative 16-channels SDD based spectrometer specifically designed for X-ray fluorescence microscopy (XFM) imaging in synchrotron beamlines. The detector will feature a backscattering geometry with a tilted SDD layout achieving 1 sr solid angle at 8 mm sample distance and a potential Output Count Rate higher than 20 Mcps. The 1 mm thick SDD provides 65 % absorption efficiency at 20 keV while preserving a good energy resolution better than 150 eV thanks to a dedicated cooling system and a low noise front-end electronics. In this paper, the optimization of the detector geometry, in terms of solid angle vs sample distance and maximization of the Output Count Rate introducing a tilting of the SDD units, is discussed.

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Refaat, Tamer, Derek West, Samar Elachy, Vamsi Parimi, Jasmine May, Kathleen R. Harris, Andrew C. Larson, Reed A. Omary, Tatjana Paunesku, and Gayle Woloschak. "The study of in vivo acute effect of two different delivery modalities of iron oxide core with titanium dioxide shell nanoparticles in rabbits liver tumor." Journal of Clinical Oncology 31, no. 15_suppl (May 20, 2013): e22204-e22204. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.e22204.

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e22204 Background: To compare intravenous (IV) versus fluoroscopy-guided transarterial intra-catheter (IC) delivery of iron oxide core with titanium dioxide shell nanoparticles (NPs) in vivo in VX2 model of liver cancer in rabbits and detect the NPs distribution and effect of NPs presence on the target tumor and other rabbit’s organs. Methods: After obtaining the IACUC approval, liver tumors were obtained by implantation of tumor tissue obtained from a hind limb VX2 tumor of donor rabbits. NPs were delivered either IV or IC. After rabbit termination, 2 hours post NPs injection, tumor, liver, kidney, lung and spleen were harvested, split in half and a part of it was frozen while the remainder was formalin fixed and paraffin embedded. To assess the NPs distribution in 2D we stained 5um thick paraffin tissue sections using Dopamine-Biotin-DHS histochemical (HC) staining followed by Nanozoomer microscopy analysis. H and E staining, TUNEL assay and Ki67 immunohistochemistry were also done. X-ray Fluorescence Microscopy (XFM) was used to quantify the NPs. Frozen tissue was used for bulk NPs concentration analysis using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Results: This study included ten rabbits; 3 rabbits had IV NPs injections, 3 had IC NPs injection, 2 control and 2 donors. ICP-MS analysis showed statistically significant higher NPs concentration in tumors of IC arm vs. IV arm (p= 0.0356), while there was higher concentration of NPs in liver (p=0.00077) and spleen (p = 0.01356) of IV vs. IC arms but no difference in kidneys or lungs. These findings were consistent with results from HC and XFM analyses. HC 2D analysis of NPs distribution showed that the RES have taken up the NPs non-specifically. There were no statistically significant differences between the treatment groups regarding the Ki67 proliferation or the TUNEL apoptosis indices or when control rabbits were compared to NPs treated rabbits. Conclusions: Both IV and IC NPs injection are feasible modalities for delivering NPs to tumors with acceptable acute systemic effects and comparable tumor effect. IV delivery increased sequestration of the NPs by RES and their accumulation in spleen and liver.

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Li, Xiaoyan, Jie He, and Jian Sun. "LOXL1 gene polymorphisms are associated with exfoliation syndrome/exfoliation glaucoma risk: An updated meta-analysis." PLOS ONE 16, no. 4 (April 28, 2021): e0250772. http://dx.doi.org/10.1371/journal.pone.0250772.

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Background Single nucleotide polymorphisms (SNPs) in the gene encoding LOXL1 are risk factors for exfoliation syndrome and exfoliation glaucoma. This meta-analysis comprehensively investigated the association between LOXL1 gene polymorphisms (rs1048661, rs3825942, and rs2165241) and the risk of exfoliation syndrome/exfoliation glaucoma (XFS)/(XFG). Methods All eligible case-control studies, published before August 17, 2020, were searched on Medline (Ovid), PubMed, CNKI, EMBASE, and Wanfang databases. Results In total, 5022 cases and 8962 controls were included in this meta-analysis. Significant associations between LOXL1 gene polymorphisms and XFS/XFG risk was observed in the disease types-based subgroups. In addition, in the subgroup analysis of ethnicity, positive associations between LOXL1 gene polymorphisms (rs1048661, rs3825942, and rs2165241) and XFS/XFG risk were found in Caucasians. Furthermore, rs1048661 and rs3825942 polymorphisms were related to XFS/ XFG risk in Asians; however, no significant association was observed between the LOXL1 gene rs2165241 polymorphism and XFS/XFG risk in Asians. In addition, rs1048661 and rs3825942 correlated with XFS/XFG susceptibility in Africans. Conclusions Our results implicate LOXL1 gene polymorphisms as XFS/XFG risk factors, especially in Caucasians.

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Ramsay, Stuart C., Nathan Cassidy, Martin D. de Jonge, Daryl L. Howard, David Paterson, and Natkunam Ketheesan. "Examination of trafficking of phagocytosed colloid particles in neutrophils using synchrotron-based X-ray fluorescence microscopy (XFM)." Journal of Biological Physics 37, no. 4 (August 26, 2011): 493–506. http://dx.doi.org/10.1007/s10867-011-9233-9.

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Ma, Yi-Nu, Ting-Yu Xie, and Xue-Yi Chen. "Multiple Gene Polymorphisms Associated with Exfoliation Syndrome in the Uygur Population." Journal of Ophthalmology 2019 (May 2, 2019): 1–8. http://dx.doi.org/10.1155/2019/9687823.

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Background. Our previous data suggested that three single-nucleotide polymorphisms (SNPs), rs1048661, rs3825942, and rs2165241, of the lysyl oxidase-like 1 gene (LOXL1) are significantly associated with exfoliation syndrome (XFS) and exfoliation glaucoma (XFG). The following study investigated other SNPs that potentially effect XFS/XFG. Methods. A total of 216 Uygur patients diagnosed with XFS/XFG, and 297 Uygur volunteers were admitted to the First Affiliated Hospital at Xinjiang Medical University between January 2015 and October 2017. Blood samples were collected by venipuncture. Alleles and genotypes of LOXL1, TBC1D21, ATXN2, APOE, CLU, AFAP1, TXNRD2, CACNA1A, ABCA1, GAS7, and CNTNAP2 were analyzed by direct sequencing. Results. The allele G of rs41435250 of LOXL1 was a risk allele for XFS/XFG (P<0.001), whereas the allele G of rs893818 of LOXL1 was a protective allele for XFS/XFG (P<0.001). After adjusting all data for age and gender, the following results were obtained: the frequency of genotype CC for rs7137828 of ATXN2 was significantly higher in XFS/XFG patients than in controls (P=0.027), while no significance was found with reference to the frequency of genotype TT. The frequency of genotype GG for rs893818 of LOXL1 (P<0.001) and the frequency of genotype AA were both significantly higher in XFS/XFG groups compared to the control group (P<0.001). In addition, the frequency of genotype TT for rs41435250 of LOXL1 was higher in XFS/XFG patients than in controls (P=0.003), while no significant difference was found with reference to the frequency of genotype GG after adjusting for age and gender. In addition, the haplotypes G-A/T-G/G-G for rs41435250 and rs893818 were significantly associated with XFS/G. Conclusions. With reference to LOXL1, the rs41435250 resulted as a risk factor and rs893818 as a protective factor for XFS/XFG in the Uygur populations. Meanwhile, the rs16958445 of TBC1D21 and the rs7137828 of ATXN2 have also shown to be associated with pathogenesis of XFS/XFG.

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Paulson, Chase, Samuel C. Thomas, Orlando Gonzalez, Samuel Taylor, Cole Swiston, Jennifer S. Herrick, Lori McCoy, et al. "Exfoliation Syndrome in Baja Verapaz Guatemala: A Cross-Sectional Study and Review of the Literature." Journal of Clinical Medicine 11, no. 7 (March 24, 2022): 1795. http://dx.doi.org/10.3390/jcm11071795.

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There are little epidemiologic data on exfoliation syndrome (XFS) or exfoliation glaucoma (XFG) in Guatemala, especially in the underserved Baja Verapaz region. This observational study assessing XFS/XFG and demographic factors of this region aims to better understand unique exogenous and endogenous risk factors associated with XFS/XFG in Guatemala. During Moran Eye Center’s global outreach medical eye camps from 2016–2017, 181 patients age 15 years and older presented for complete eye exams. These individuals were screened for eye disease and evaluated for possible surgical interventions that could occur during the camps to improve eyesight. During the dilated exams, XFS was noted as missing or present. Of those 181, 10 had insufficient data and 18 lacked a definitive diagnosis of XFS or XFG, resulting in 153 evaluable patients; 46 XFS and 9 XFG were identified. Age, gender, hometown, ancestry (languages spoken by parents and grandparents), past medical history, family medical history, and occupational data (only 2017 trip) were obtained for each patient. The most common occupations of these individuals were farming and housekeeping. Higher rates of XFS/XFG were noted in individuals of rural compared to urban settings and Mayan speaking people compared with Spanish speakers. Based on this subset of patients, with various ocular pathologies being evaluated during medical eye outreach camps, the prevalence of XFS/XFG appeared to be 36%, a high prevalence compared to other world populations. Location and higher altitude, along with a farming occupation, may contribute to XFS development and subsequent progression to XFG. To our knowledge, this is the largest study looking at the epidemiology of XFS/XFG in the Baja Verapaz region of Guatemala for those over the age of 15 years seeking eye exams and interventions.

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Toptan, Müslüm, and Ali Simsek. "Evaluation of the Effect of Duration on Retinal Nerve Fiber Layer Thickness and Choroidal Thickness in Exfoliation Syndrome and Exfoliative Glaucoma." Diagnostics 13, no. 2 (January 14, 2023): 314. http://dx.doi.org/10.3390/diagnostics13020314.

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Aims: To compare retinal nerve fiber layer (RNFL) thickness and choroidal thickness in patients with exfoliation syndrome (XFS) and exfoliative glaucoma (XFG) for 1–5 years or 6–10 years compared to healthy volunteers. Methods and Material: Seventy-eight eyes of 78 patients with XFG, 78 eyes of 78 patients with XFS, and 83 eyes of 83 healthy individuals were included in this prospective study. SD-OCT data for choroid thickness and RNFL were recorded. Results: RNFL thickness was statistically significantly lower in eyes with XFG and XFS than in the control group (p < 0.001). Macular choroidal thickness decreased significantly in the XFG group compared to the XFS and control groups (p < 0.001). No significant difference was observed between the XFS and control groups (p > 0.05). In terms of choroidal and RNFL thicknesses by years in XFG and XFS patients, values were lower in the patients diagnosed 6–10 years previously than in those diagnosed 1–5 years previously. However, the difference was not statistically significant (p > 0.05). Conclusions: Thinning of both choroidal and RNLF thickness in XFG and XFS patients may mean that PEX material is an important risk factor for the progression of XFS to XFG. In addition, thinner choroid and RNLF thickness in the 6–10 years groups show the effect of PEX material and the importance of time.

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Patil, Ayesha, Cole Swiston, Ryan T. Wallace, Chase Paulson, Matthew E. Conley, Lori McCoy, Craig Chaya, and Barbara Wirostko. "Exfoliation Syndrome and Exfoliation Glaucoma in the Navajo Nation." Vision 6, no. 4 (October 3, 2022): 61. http://dx.doi.org/10.3390/vision6040061.

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(1) Background: Exfoliation syndrome (XFS) is a common cause of secondary open angle glaucoma. In 1971, Faulkner et al. estimated the prevalence of XFS among 50 Navajo Nation residents as 38%. Given that XFS can cause irreversible blindness secondary to glaucoma (XFG), this study aims to identify the current prevalence of XFS among Navajo Nation residents within the Four Corners region of the U.S. (2) Methods: A retrospective chart review was conducted from 2016 to 2021 for patients aged 18 and older. All patients with XFS or XFG diagnosed by slit lamp exam were identified through chart review. (3) Results: Of the 1152 patient charts available for review, eight patients (11 eyes) were diagnosed with XFS with three patients (4 eyes) demonstrating concomitant XFG. Within this XFS population, 50% of the patients identified as male, with a mean age of 73 years. The overall prevalence of XFS was 0.7% and the overall prevalence of XFG was found to be 0.26%. The rate of XFG among patients with XFS was 37.5%. (4) Conclusion: Compared to Faulkner’s study of Navajo Nation residents in 1971, our findings show a considerably lower prevalence of XFS at 0.7%. We present the largest study to date of XFS among this population.

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Weekley, Claire M., Anu Shanu, Jade B. Aitken, Stefan Vogt, Paul K. Witting, and Hugh H. Harris. "XAS and XFM studies of selenium and copper speciation and distribution in the kidneys of selenite-supplemented rats." Metallomics 6, no. 9 (2014): 1602–15. http://dx.doi.org/10.1039/c4mt00088a.

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Zelinka, Samuel L., Sophie-Charlotte Gleber, Stefan Vogt, Gabriela M. Rodríguez López, and Joseph E. Jakes. "Threshold for ion movements in wood cell walls below fiber saturation observed by X-ray fluorescence microscopy (XFM)." Holzforschung 69, no. 4 (May 1, 2015): 441–48. http://dx.doi.org/10.1515/hf-2014-0138.

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Abstract Diffusion of chemicals and ions through the wood cell wall plays an important role in wood damage mechanisms. In the present work, free diffusion of ions through wood secondary walls and middle lamellae has been investigated as a function of moisture content (MC) and anatomical direction. Various ions (K, Cl, Zn, Cu) were injected into selected regions of 2 μm thick wood sections with a microinjector and then the ion distribution was mapped by means of X-ray fluorescence microscopy with submicron spatial resolution. The MC of the wood was controlled in situ by means of climatic chamber with controlled relative humidity (RH). For all ions investigated, there was a threshold RH below which the concentration profiles did not change. The threshold RH depended upon ionic species, cell wall layer, and wood anatomical orientation. Above the threshold RH, differences in mobility among ions were observed and the mobility depended upon anatomical direction and cell wall layer. These observations support a recently proposed percolation model of electrical conduction in wood. The results contribute to understanding the mechanisms of fungal decay and fastener corrosion that occur below the fiber saturation point.

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Fu, Y., N. Azene, T. Ehtiati, A. Flammang, J. Guerhing, W. Gilson, J. A. Cook, et al. "X-ray fused magnetic resonance imaging (XFM) for intrapericardial delivery of x-ray–visible human mesenchymal stem cells." Journal of Vascular and Interventional Radiology 23, no. 8 (August 2012): 1115. http://dx.doi.org/10.1016/j.jvir.2012.05.024.

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George, Ashvin K., Merdim Sonmez, Robert J. Lederman, and Anthony Z. Faranesh. "Robust automatic rigid registration of MRI and X-ray using external fiducial markers for XFM-guided interventional procedures." Medical Physics 38, no. 1 (December 16, 2010): 125–41. http://dx.doi.org/10.1118/1.3523621.

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Hues, Steven M., Richard J. Colton, Ernst Meyer, and Hans-Joachim Güntherodt. "Scanning Probe Microscopy of Thin Films." MRS Bulletin 18, no. 1 (January 1993): 41–49. http://dx.doi.org/10.1557/s088376940004344x.

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Atomic force microscopy (AFM) was invented in 1986 by Binnig, Quate, and Gerber as “a new type of microscope capable of investigating surfaces of insulators on an atomic scale.” Stemming from developments in scanning tunneling microscopy (STM), it became possible to image insulators, organic and biological molecules, salts, glasses, and metal oxides — some under a variety of conditions, e.g., ambient pressure, in aqueous or cryogenic liquids, etc. In 1987, Mate and co-workers introduced a new application for AFM where atomic-scale frictional forces could be measured. Likewise, in 1989, Burnham and Colton used the AFM to measure the surface forces and nano-mechanical properties of materials. Today, there are many examples of using AFM as a high-resolution profilometer, surface force probe, and nanoindentor. Several new imaging techniques have been introduced; each depending on the type of force measured, e.g., magnetic, electrostatic, and capacitative. Because of the diverse nature of the field and instrumentation, the names “scanned probe microscopy” and “XFM” (where X stands for the force being measured, e.g., MFM is magnetic force microscopy) have been adopted.

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Jones, Michael W. M., Grant A. van Riessen, Nicholas W. Phillips, Christoph E. Schrank, Gerard N. Hinsley, Nader Afshar, Juliane Reinhardt, Martin D. de Jonge, and Cameron M. Kewish. "High-speed free-run ptychography at the Australian Synchrotron." Journal of Synchrotron Radiation 29, no. 2 (January 17, 2022): 480–87. http://dx.doi.org/10.1107/s1600577521012856.

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Over the last decade ptychography has progressed rapidly from a specialist ultramicroscopy technique into a mature method accessible to non-expert users. However, to improve scientific value ptychography data must reconstruct reliably, with high image quality and at no cost to other correlative methods. Presented here is the implementation of high-speed ptychography used at the Australian Synchrotron on the XFM beamline, which includes a free-run data collection mode where dead time is eliminated and the scan time is optimized. It is shown that free-run data collection is viable for fast and high-quality ptychography by demonstrating extremely high data rate acquisition covering areas up to 352 000 µm2 at up to 140 µm2 s−1, with 13× spatial resolution enhancement compared with the beam size. With these improvements, ptychography at velocities up to 250 µm s−1 is approaching speeds compatible with fast-scanning X-ray fluorescence microscopy. The combination of these methods provides morphological context for elemental and chemical information, enabling unique scientific outcomes.

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Foucher, Alexandre, Nicholas Marcella, Anna Plonka, Anatoly Frenkel, and Eric Stach. "Using in situ electron energy-loss spectroscopy (EELS) and X-ray fluorescence microscopy (XFM) to characterize Co-Pt nanoparticles." Microscopy and Microanalysis 27, S1 (July 30, 2021): 2108–9. http://dx.doi.org/10.1017/s1431927621007613.

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Haddad, Marie Reine, Martina Ralle, David J. Vine, Patricia M. Zerfas, and Stephen G. Kaler. "356. High-Resolution X-Ray Fluorescence Microscopy (XFM) Indicates Enhanced Brain Copper Delivery in AAV9-Treated Menkes Disease Mice." Molecular Therapy 24 (May 2016): S142—S143. http://dx.doi.org/10.1016/s1525-0016(16)33165-3.

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Wedding, Jason L., Barry Lai, Stefan Vogt, and Hugh H. Harris. "Investigation into the intracellular fates, speciation and mode of action of selenium-containing neuroprotective agents using XAS and XFM." Biochimica et Biophysica Acta (BBA) - General Subjects 1862, no. 11 (November 2018): 2393–404. http://dx.doi.org/10.1016/j.bbagen.2018.03.031.

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Saatcioglu, F., D. J. Perry, D. S. Pasco, and J. B. Fagan. "Multiple DNA-binding factors interact with overlapping specificities at the aryl hydrocarbon response element of the cytochrome P450IA1 gene." Molecular and Cellular Biology 10, no. 12 (December 1990): 6408–16. http://dx.doi.org/10.1128/mcb.10.12.6408-6416.1990.

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Three nuclear factors, the Ah receptor, XF1, and XF2, bind sequence specifically to the Ah response elements or xenobiotic response elements (XREs) of the cytochrome P450IA1 (P450c) gene. The interactions of these factors with the Ah response element XRE1 were compared by three independent methods, methylation interference footprinting, orthophenanthroline-Cu+ footprinting, and mobility shift competition experiments, using a series of synthetic oligonucleotides with systematic alterations in the XRE core sequence. These studies established the following (i) all three factors interact sequence specifically with the core sequence of XRE1; (ii) the pattern of contacts made with this sequence by the Ah receptor are different from those made by XF1 and XF2; and (iii) although XF1 and XF2 can be distinguished by the mobility shift assay, the sequence specificities of their interactions with XRE1 are indistinguishable. Further characterization revealed the following additional differences among these three factors: (i) XF1 and XF2 could be extracted from nuclei under conditions quite different from those required for extraction of the Ah receptor; (ii) XF1 and XF2 were present in the nuclei of untreated cells and did not respond to polycyclic compounds, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and beta-napthoflavone, while nuclear Ah receptor was undetectable in untreated cells and rapidly increased in response to TCDD; (iii) inhibition of protein synthesis did not affect the TCDD-induced appearance of the Ah receptor but substantially decreased the constitutive activities of XF1 and XF2, suggesting that the Ah receptor must be present in untreated cells in an inactive form that can be rapidly activated by polycyclic compounds, while the constitutive expression of XF1 and XF2 depends on the continued synthesis of a relatively unstable protein; (iv) the receptor-deficient and nuclear translocation-defective mutants of the hepatoma cell line Hepa1, which are known to lack nuclear Ah receptor, expressed normal levels of XF1 and XF2, suggesting that the former factor is genetically distinct from the latter two; and (v) a divalent metal ion, probably Zn2+, is known to be an essential cofactor for the Ah receptor but was not required for the DNA-binding activities of XF1 and XF2. Together, these findings indicate that the Ah receptor is distinct from XF1 and XF2, while the latter two activities may be related. Because the DNA-binding domains of these three factors overlap substantially, their binding to XREs is probably mutually exclusive, which suggests that the interplay of these factors at Ah response elements may be important to the regulation of CYP1A1 gene transcription. The results of preliminary transfection experiments with constructs harboring XREs upstream of the chloramphenicol acetyltransferase gene driven by a minimal simian virus 40 promoter are presented that are consistent with this hypothesis.

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Saatcioglu, F., D. J. Perry, D. S. Pasco, and J. B. Fagan. "Multiple DNA-binding factors interact with overlapping specificities at the aryl hydrocarbon response element of the cytochrome P450IA1 gene." Molecular and Cellular Biology 10, no. 12 (December 1990): 6408–16. http://dx.doi.org/10.1128/mcb.10.12.6408.

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Three nuclear factors, the Ah receptor, XF1, and XF2, bind sequence specifically to the Ah response elements or xenobiotic response elements (XREs) of the cytochrome P450IA1 (P450c) gene. The interactions of these factors with the Ah response element XRE1 were compared by three independent methods, methylation interference footprinting, orthophenanthroline-Cu+ footprinting, and mobility shift competition experiments, using a series of synthetic oligonucleotides with systematic alterations in the XRE core sequence. These studies established the following (i) all three factors interact sequence specifically with the core sequence of XRE1; (ii) the pattern of contacts made with this sequence by the Ah receptor are different from those made by XF1 and XF2; and (iii) although XF1 and XF2 can be distinguished by the mobility shift assay, the sequence specificities of their interactions with XRE1 are indistinguishable. Further characterization revealed the following additional differences among these three factors: (i) XF1 and XF2 could be extracted from nuclei under conditions quite different from those required for extraction of the Ah receptor; (ii) XF1 and XF2 were present in the nuclei of untreated cells and did not respond to polycyclic compounds, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and beta-napthoflavone, while nuclear Ah receptor was undetectable in untreated cells and rapidly increased in response to TCDD; (iii) inhibition of protein synthesis did not affect the TCDD-induced appearance of the Ah receptor but substantially decreased the constitutive activities of XF1 and XF2, suggesting that the Ah receptor must be present in untreated cells in an inactive form that can be rapidly activated by polycyclic compounds, while the constitutive expression of XF1 and XF2 depends on the continued synthesis of a relatively unstable protein; (iv) the receptor-deficient and nuclear translocation-defective mutants of the hepatoma cell line Hepa1, which are known to lack nuclear Ah receptor, expressed normal levels of XF1 and XF2, suggesting that the former factor is genetically distinct from the latter two; and (v) a divalent metal ion, probably Zn2+, is known to be an essential cofactor for the Ah receptor but was not required for the DNA-binding activities of XF1 and XF2. Together, these findings indicate that the Ah receptor is distinct from XF1 and XF2, while the latter two activities may be related. Because the DNA-binding domains of these three factors overlap substantially, their binding to XREs is probably mutually exclusive, which suggests that the interplay of these factors at Ah response elements may be important to the regulation of CYP1A1 gene transcription. The results of preliminary transfection experiments with constructs harboring XREs upstream of the chloramphenicol acetyltransferase gene driven by a minimal simian virus 40 promoter are presented that are consistent with this hypothesis.

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Dimmock, Matthew Richard, Martin Daly de Jonge, Daryl Lloyd Howard, Simon Alexander James, Robin Kirkham, David Maurice Paganin, David John Paterson, Gary Ruben, Chris Gregory Ryan, and Jeremy Michael Cooney Brown. "Validation of aGeant4model of the X-ray fluorescence microprobe at the Australian Synchrotron." Journal of Synchrotron Radiation 22, no. 2 (February 14, 2015): 354–65. http://dx.doi.org/10.1107/s1600577515000223.

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AGeant4Monte Carlo simulation of the X-ray fluorescence microprobe (XFM) end-station at the Australian Synchrotron has been developed. The simulation is required for optimization of the scan configuration and reconstruction algorithms. As part of the simulation process, a Gaussian beam model was developed. Experimental validation of this simulation has tested the efficacy for use of the low-energy physics models inGeant4for this synchrotron-based technique. The observed spectral distributions calculated in the 384 pixel Maia detector, positioned in the standard back-scatter configuration, were compared with those obtained from experiments performed at three incident X-ray beam energies: 18.5, 11.0 and 6.8 keV. The reduced χ-squared (\chi^{2}_{\rm{red}}) was calculated for the scatter and fluorescence regions of the spectra and demonstrates that the simulations successfully reproduce the scatter distributions. Discrepancies were shown to occur in the multiple-scatter tail of the Compton continuum. The model was shown to be particularly sensitive to the impurities present in the beryllium window of the Maia detector and their concentrations were optimized to improve the \chi^{2}_{\rm{red}} parameterization in the low-energy fluorescence regions of the spectra.

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Janicijevic, Katarina, Sanja Kocic, Sladjana Pajovic, Nemanja Zdravkovic, Tatjana Sarenac-Vulovic, and Mirjana Janicijevic-Petrovic. "The importance of developing atherosclerosis in pseudoexfoliation glaucoma." Vojnosanitetski pregled 74, no. 1 (2017): 8–12. http://dx.doi.org/10.2298/vsp150320058j.

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Background/Aim. Pseudoexfoliation syndrome (XPS) is an age-related systemic disorder characterized by increased production and accumulation of elastic microfibrillar material in different tissues of the body: skin, connective tissue portions of visceral organs, periphery blood vessels and the eye, as well. The aim of our study was to determine the significance of atherosclerotic changes in the carotid arteries in the development of XFS and pseudoexfoliation glaucoma (XFG). Methods. The study included 120 patients ? 40 patients per each of the three defined groups: XFS group, XFG group and age- and sex-matched control subjects (control group) without XFG. Blood samples were collected from the patients before cataract surgery. Serum levels of total cholesterol, low-density lipoprotein ? LDL, high density lipoprotein ? HDL and triglycerides were analyzed by standard laboratory techniques. Standard ultrasonography of the carotid blood vessels was performed in all the participants. Results. Lipid?s profile was disturbed in the patients with XFS and XFG with statistical significance p control group (p < 0.01). Systolic and diastolic pressure was elevated in the patients with XFS and XFG (p < 0.01). Resistance index was increased in the patients with XFG (p < 0.01). Intima-media thickness was prolonged in patients with XFG (p < 0.01). Conclusion. A disturbed lipid profile with elevated resistancy index and intima-media thickness and increased systolic and diastolic pressure were compulsory findings in patients with developed XFG. So, these factors could be considered as risk. It seems to be difficult to inhibit the process of pseudoexfolation production in the whole body, but it appears that with proper therapy (antihypertnesive, cardiotoncs, etc.) and adequate nourishing, the process of XFG development could be interrupted.

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Fu, Y., N. Azene, T. Ehtiati, A. Flammang, J. Guerhing, W. Gilson, J. A. Cook, et al. "Abstract No. 428: X-ray fused magnetic resonance imaging (XFM) for intrapericardial delivery of X-ray-visible human mesenchymal stem cells." Journal of Vascular and Interventional Radiology 23, no. 3 (March 2012): S170. http://dx.doi.org/10.1016/j.jvir.2012.01.025.

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Journal articles on the topic 'XFM'

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