46 results on '"Steenackers M"'
Search Results
2. The Use of Bulked Segregant Analysis to Identify AFLP™ Molecular Markers Closely Linked to Melampsora Larici-Populina Resistance in Populus
- Author
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Cervera, M.-T., GusmãO, J., Steenackers, M., Storme, V., Broeck, A. Vanden, Van Montagu, M., Boerjan, W., Ahuja, M. Raj, editor, Boerjan, Wout, editor, and Neale, David B., editor
- Published
- 1996
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3. Diseases of poplars and willows.
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Ostry, M., primary, Ramstedt, M., additional, Newcombe, G., additional, and Steenackers, M., additional
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- 2014
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4. Es nog steeds bedreigd door Aziatische schimmel
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Sioen, G., Verschelde, P., Haeck, A. de, Roskams, P., Steenackers, M., Cuyper, B. de, Sioen, G., Verschelde, P., Haeck, A. de, Roskams, P., Steenackers, M., and Cuyper, B. de
- Abstract
Het gaat niet goed met de gezondheidstoestand van de es (Fraxinus excelsior L.). Een tiental jaren geleden bemerkten bosbeheerders op verschillende plaatsen in Vlaanderen sterfte van jonge essenaanplantingen. In Bosrevue 39 verscheen een artikel met een beschrijving van de essenziekte (Roskams & De Haeck, 2012). De schimmel kreeg toen de naam Hymenoscyphus pseudoalbidus maar was beter bekend onder de naam van de ongeslachtelijke vorm Chalara fraxinea. De herkomst van de ziekteverwekkende schimmel was nog onduidelijk. De gevolgen van de ziekte waren wel opvallend, zeker voor jonge boompjes.
- Published
- 2021
5. Multifunctional SiC Surfaces
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Schoell, S.J., primary, Oliveros, A., additional, Steenackers, M., additional, Saddow, S.E., additional, and Sharp, I.D., additional
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- 2012
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6. Identification of AFLP molecular markers for resistance against Melampsora larici-populina in Populus
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Cervera, M. T., Gusmão, J., Steenackers, M., Peleman, J., Storme, V., Vanden Broeck, A., Van Montagu, M., and Boerjan, W.
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- 1996
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7. PCR-based detection of the causal agent of watermark disease in willows (Salix spp.)
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Hauben, L., Steenackers, M., and Swings, J.
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Polymerase chain reaction -- Usage ,Pathogenic microorganisms -- Research ,Willows -- Research ,Biological sciences - Abstract
A study was conducted to analyze the polymerase chain detection (PCR) detection of the watermark disease pathogen in the vascular fluid of willows. Decimal Brenneria salicis suspension dilutions were determined in phosphate-buffered saline to obtain the sensitivity of PCR detection. Vascular fluid was then utilized to evaluate the efficiency of PCR in plant material. Moreover, dilutions were used for PCR and placed on a GYCA medium.
- Published
- 1998
8. The Use of Bulked Segregant Analysis to Identify AFLP™ Molecular Markers Closely Linked to Melampsora Larici-Populina Resistance in Populus
- Author
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Cervera, M.-T., primary, GusmãO, J., additional, Steenackers, M., additional, Storme, V., additional, Broeck, A. Vanden, additional, Van Montagu, M., additional, and Boerjan, W., additional
- Published
- 1996
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9. Aanpassing herkomstgebiedafbakening voor boom- en struiksoorten in Vlaanderen
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Mijnsbrugge, K. Vander, Steenackers, M., Smet, L. De, Mijnsbrugge, K. Vander, Steenackers, M., and Smet, L. De
- Published
- 2017
10. Observing the Sun with micro-interferometric devices: a didactic experiment
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Defrère, D, Absil, O, Hanot, C, Riaud, P, Magette, A, Marion, L, Wertz, O, Finet, F, Steenackers, M, Habraken, S, Surdej, A, Surdej, J, Arnold, L, Le Coroller, H, and Surdej, J
- Abstract
keywords: optical interferometry, delay-lines, sparse apertures, beam combiners, fringe tracking, laser telemetry, heterodyne interferometry, image reconstruction, nulling interferometry adsurl: https://ui.adsabs.harvard.edu/abs/2014ipco.conf...87D adsnote: Provided by the SAO/NASA Astrophysics Data System ispartof: pages:87-92 ispartof: Improving the Performances of Current Optical Interferometers & Future Designs pages:87-92 ispartof: Improving the performances of current optical interferometers & future designs location:Observatoire de Haute Provence, France status: published
- Published
- 2014
11. CREATING A CAPABILITY BUILDING PROGRAM BASED ON PATIENT COMMUNITY'S ACTUAL NEEDS AND PRIORITIES: THE SJÖGREN EUROPE EXPERIENCE.
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Antonopoulou, K., Vieira, A., Bouillot, C., Koelewijn-Tukker, J., Oosterbaan, M., Steenackers, M., and Gousset, V. Lopez
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- 2023
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12. Chapter 3 - Multifunctional SiC Surfaces: From Passivation to Biofunctionalization
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Schoell, S.J., Oliveros, A., Steenackers, M., Saddow, S.E., and Sharp, I.D.
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- 2012
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13. Nanostructured polymer brushes and protein density gradients on diamond by carbon templating
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Hutter, N.A., Steenackers, M., Reitinger, A., Williams, O.A., Garrido, J.A., Jordan, R., and Publica
- Abstract
Micro- and nanostructured polymer brushes on diamond can be directly prepared by carbon templating and amplification of the latent structures by photografting of a broad variety of vinyl monomers such as styrenes, acrylates and methacrylates. Even template structures with lateral dimensions as small as 5 nm can be selectively amplified and defined polymer brush gradients of a variety of functional polymers are realizable by this technique. Furthermore, conjugation with a model protein (GFP) results in protein density gradients of high loading and improved chemical stability. The effective functionalization of chemically and biologically inert diamond surfaces with stable functional polymer brushes, the possibility of structuring by the carbon templating technique and the direct biofunctionalization are crucial steps for the development of diamond based biosensors.
- Published
- 2011
14. Microstructured poly(2-oxazoline) bottle-brush brushes on nanocrystalline diamond
- Author
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Hutter, N.A., Reitinger, A., Zhang, N., Steenackers, M., Williams, O.A., Garrido, J.A., Jordan, R., and Publica
- Abstract
We report on the preparation of microstructured poly(2-oxazoline) bottle-brush brushes (BBBs) on nanocrystalline diamond (NCD). Structuring of NCD was performed by photolithography and plasma treatment to result in a patterned NCD surface with oxidized and hydrogenated areas. Self-initiated photografting and photopolymerization (SIPGP) of 2-isopropenyl-2-oxazoline (IPOx) resulted in selective grafting of poly(2-isopropenyl-2-oxazoline) (PIPOx) polymer brushes only at the oxidized NCD areas. Structured PIPOx brushes were converted by methyl triflate into the polyelectrolyte brush macroinitiator for the living cationic ring-opening polymerization (LCROP) of 2-oxazolines. The LCROP was performed with 2-ethyl-2-oxazoline (EtOx) as well as 2-(carbazolyl)ethyl-2-oxazoline (CarbOx) as monomers, resulting in structured bottle-brush brushes (BBB) with different pendant side chains and functionalities. FT-IR spectroscopy, fluorescence microscopy, and AFM measurements indicated a high side chain grafting density as well as quantitative and selective reactions. Poly(2-oxazoline) BBBs containing hole conducting carbazole moieties on NCD as electrode material may open the way to advanced amperometric biosensing systems.
- Published
- 2010
15. Wat gaat er mis met onze populieren?
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Michiels, B., Roskams, P., Steenackers, M., Slycken, J. van, Michiels, B., Roskams, P., Steenackers, M., and Slycken, J. van
- Abstract
Heel wat populierenbosjes stonden er in 2003 niet zo florissant bij. We gaan in deze bijdrage dieper in op de oorzaken en mogelijke oplossingen.
- Published
- 2004
16. Differential host-pathogen interactions among clones of poplar and strains of Xanthomonas populi pv. populi
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Nesme, Xavier, Steenackers, M., Steenackers, V., Picard, C., Ridé, S., Ridé, M., ProdInra, Migration, Unité de recherche Pathologie végétale et phytobactériologie, and Institut National de la Recherche Agronomique (INRA)
- Subjects
[SDV] Life Sciences [q-bio] ,[SDV]Life Sciences [q-bio] ,PEUPLIER ,RESISTANCE - Published
- 1994
17. Monitoring of endophytic Brenneria salicis in willow and its relation to watermark disease
- Author
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Maes, M., primary, Baeyen, S., additional, De Croo, H., additional, De Smet, K., additional, and Steenackers, M., additional
- Published
- 2002
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18. Fine Mapping and Identification of Nucleotide Binding Site/Leucine-Rich Repeat Sequences at the MER Locus in Populus deltoides ‘S9-2’
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Zhang, J., primary, Steenackers, M., additional, Storme, V., additional, Neyrinck, S., additional, Van Montagu, M., additional, Gerats, T., additional, and Boerjan, W., additional
- Published
- 2001
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19. Poplar diseases, consequences on growth and wood quality
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Steenackers, J., primary, Steenackers, M., additional, Steenackers, V., additional, and Stevens, M., additional
- Published
- 1996
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20. Exchange of genetic material
- Author
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Steenackers, V., primary, Hall, R., additional, Steenackers, M., additional, and Smets, P., additional
- Published
- 1992
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21. Collection and distribution of poplar species, hybrids and clones
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Steenackers, V., primary, Strobl, S., additional, and Steenackers, M., additional
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- 1990
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22. Cell-specific and conditional expression of caffeoyl-coenzyme A-3-O-methyltransferase in poplar.
- Author
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Chen, C, Meyermans, H, Burggraeve, B, De Rycke, R M, Inoue, K, De Vleesschauwer, V, Steenackers, M, Van Montagu, M C, Engler, G J, and Boerjan, W A
- Abstract
Caffeoyl coenzyme A-3-O-methyltransferase (CCoAOMT) plays an important role in lignin biosynthesis and is encoded by two genes in poplar (Populus trichocarpa). Here, we describe the expression pattern conferred by the two CCoAOMT promoters when fused to the gus-coding sequence in transgenic poplar (Populus tremula x Populus alba). Both genes were expressed similarly in xylem and differentially in phloem. In xylem, expression was preferentially observed in vessels and contact rays, whereas expression was barely detectable in storage rays and fibers, suggesting different routes to monolignol biosynthesis in the different xylem types. Furthermore, after wounding, fungal infection, and bending, the expression of both genes was induced concomitantly with de novo lignin deposition. Importantly, upon bending and leaning of the stem, the cell-specific expression pattern was lost, and both genes were expressed in all cell types of the xylem. CCoAOMT promoter activity correlated well with the presence of the CCoAOMT protein, as shown by immunolocalization. These expression data may explain, at least in part, the heterogeneity in lignin composition that is observed between cell types and upon different environmental conditions.
- Published
- 2000
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23. Differentiation between Xanthomonas campestris pv. graminis (ISPP List 1980), pv. phleipratensis (ISPP List 1980) emend., pv. poae Egli and Schmidt 1982 and pv. arrhenatheri Egli and Schmidt 1982, by Numerical Analysis of Phenotypic Features and Protein Gel Electrophoregrams
- Author
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Mooter, M., primary, Steenackers, M., additional, Maertens, C., additional, Gosselé, F., additional, Vos, P., additional, Swings, J., additional, Kersters, K., additional, and Ley, J., additional
- Published
- 1987
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24. The Development and Content Validation of the Sjögren's Related Quality of Life Instrument (SRQoL).
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Marvel J, Gargon E, Howse C, Chohan A, Mayhew M, Kenney G, Stone L, Fisher BA, Steenackers M, Williamson N, Perella C, and Goswami P
- Abstract
Introduction: Several clinical outcome assessment (COA) instruments assess Sjögren's disease (Sjögren's) symptoms, but do not provide comprehensive assessment of the health-related quality of life (HRQoL) impact of Sjögren's. This study aimed to develop a patient-reported outcome (PRO) instrument for the assessment of HRQoL, intended for use in clinical trials and clinical practice in the assessment of treatment benefit., Methods: Review of study sponsor proprietary data and qualitative interviews informed the development of a conceptual model, the Sjögren's Related Quality of Life (SRQoL) and patient global impression of severity (PGI-S) and change (PGI-C) items. Combined concept elicitation and cognitive debriefing interviews with patients with Sjögren's explored their HRQoL impact experience and content validity of the SRQoL and PGI items., Results: Twenty participants were interviewed about their Sjögren's experience. Following inductive analysis of interviews, concepts were categorized into eight domains: emotional well-being (e.g., worry and stress; n = 20/20; 100%), sleep (e.g., daytime sleepiness and waking up during the night; n = 20/20; 100%), activities of daily living (e.g., difficulty looking at screens and difficulty driving; n = 20/20; 100%), cognition (e.g., concentration difficulties and word finding difficulties; n = 19/20; 95.0%), physical functioning (e.g., difficulty walking and difficulty exercising; n = 19/20; 95.0%), social and family functioning (e.g., dependent on others and relationship difficulties; n = 17/20; 85.0%), work (n = 15/20; 75.0%), and sexual functioning (n = 12/20; 60.0%). SRQoL and PGI items, instructions, response options, and recall period were well understood and relevant to participants., Conclusions: The SRQoL is a new PRO instrument to assess Sjögren's impact on HRQoL, developed in accordance with regulatory guidance. This study provides considerable insight into the patient experience of Sjögren's and evidence to support the content validity of the SRQoL. Future research should evaluate the psychometric properties of the SRQoL to support its use in clinical trials and clinical practice and further validate its use as an assessment of treatment benefit., Competing Interests: Declarations Conflict of Interest Jessica Marvel is an employee of Novartis Services Inc. Monia Steenackers, Chiara Perella, and Pushpendra Goswami are employees and shareholders of Novartis AG. Gayle Kenney was an employee and shareholder of Novartis AG at the time of this research. Elizabeth Gargon, Chloe Howse, Aishwarya Chohan, and Megan Mayhew are employees of Adelphi Values Ltd, a health outcomes agency who were paid by Novartis to conduct the research described in this manuscript. Nicola Williamson was an employee of Adelphi Values at the time of research and is now an employee and shareholder of UCB. Linda Stone has been a patient advocate representing Sjögren’s for Novartis and Servier. Benjamin Fisher has undertaken consultancy for Novartis, BMS, Servier, Galapagos, Roche, UCB, Sanofi, Janssen, Otsuka, Amgen, and AstraZeneca, and has received research funding from Janssen, Servier, Galapagos, Celgene, Novartis, and AstraZeneca. Ethical Approval Ethical approval and oversight was provided by Salus Institutional Review Board in the USA and Reading Independent Ethics Committee in the UK. Approval notices (protocol number NO9433A) were received in December 2022. The study was performed and developed in accordance with the Declaration of Helsinki and its later amendments in line with Good Clinical Practice guidelines. All subjects provided informed consent to participate in the study. Data Availability The datasets generated during and/or analyzed during the current study are not publicly available to protect participant confidentiality., (© 2024. The Author(s).)
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- 2024
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25. Epidemiology of Sjögren's: A Systematic Literature Review.
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Thurtle E, Grosjean A, Steenackers M, Strege K, Barcelos G, and Goswami P
- Abstract
Introduction: Primary Sjögren's is a multi-system autoimmune disease affecting patients' physical, mental, and emotional wellbeing. The epidemiology of Sjögren's is not well understood, and up-to-date epidemiological evidence is needed to improve knowledge and awareness of Sjögren's among patients and healthcare professionals, and to ascertain the global burden of disease. The objective of this research was to conduct a de novo systematic literature review (SLR) to identify and synthesise evidence on global epidemiology of primary Sjögren's., Methods: This SLR was conducted in May 2021 by searching MEDLINE and Embase databases, relevant conference proceedings, websites of registries, and health technology assessment agencies and databases. Publications were systematically screened for English language articles reporting on the incidence, prevalence, age at symptom onset, and age at diagnosis for people with primary Sjögren's., Results: Of 3510 records identified, 68 publications were included, representing 62 unique studies. Studies reported on age at symptom onset (16/62; 25.8%) and age at diagnosis (43/62; 69.4%) more frequently than incidence (7/62; 11.3%) and prevalence (9/62; 14.5%). Primary Sjögren's was found to have the highest incidence and prevalence in females and in older age groups (incidence: ≥65 years; prevalence: ≥75 years). Average age at onset and diagnosis of primary Sjögren's ranged between 34-57 years and 40-67 years, respectively., Conclusions: This SLR identified a paucity of incidence and prevalence data for primary Sjögren's, highlighting a need for further epidemiological studies. The global Sjögren's community must work together to follow the defined classification criteria of primary Sjögren's and reporting guidelines for incidence and prevalence data to allow for meaningful epidemiological comparisons across studies, settings, and countries., (© 2023. The Author(s).)
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- 2024
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26. Patient Experience of Sjögren's Disease and its Multifaceted Impact on Patients' Lives.
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Perella C, Steenackers M, Robbins B, Stone L, Gervais R, Schmidt T, and Goswami P
- Abstract
Introduction: The symptoms associated with Sjögren's disease (Sjögren's) are well-documented from the physician's perspective. However, from the patient's perspective, there is limited information on symptoms and their impact on health-related quality of life (HRQoL). This study aimed to provide an expanded understanding of patients' experience of Sjögren's and how symptoms impact HRQoL using a novel multi-method social media listening (SML) approach., Methods: A total of 26,950 social media posts with relevant content on Sjögren's posted by social media users from the USA, Canada, Australia, UK, France, Germany, Italy, Spain and China were analysed using an artificial intelligence natural language processing tool to explore patient conversations. Symptoms by level of impact on patients were characterised based on 'commonness' and 'bothersomeness'. Applied concept association analysis was used to assess relationships between symptom domains and impact domains. A qualitative framework was applied to explore words and phrases patients use to describe symptoms and their impacts., Results: Five of the identified symptom domains were very impactful: Pain; Dry Mouth and Throat; Fatigue, Energy and Sleep; Emotional Balance; and Dry Eye. The symptom domains Pain and Dry Mouth and Throat were the most common, while those of Emotional Balance and Fatigue, Energy and Sleep were the most bothersome. Symptom domains most closely associated with four HRQoL impact domains were Fatigue, Energy and Sleep, Dry Mouth and Throat and Dry Eye with Daily Functioning; Fatigue, Energy and Sleep with Financial Health; Emotional Balance with Psychological Wellbeing and Gynaecological Issues with Social Wellbeing., Conclusion: The results of this SML study show that Sjögren's affects diverse aspects of patients' lives, with symptoms extending beyond dry eyes and mouth and impacting daily living and functioning. Because symptoms may affect patients differently, these results highlight the importance of measuring impact on HRQoL to assess patient outcomes and treatment options in routine clinical practice and clinical trials., (© 2023. The Author(s).)
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- 2023
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27. Field and saccharification performances of poplars severely downregulated in CAD1.
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De Meester B, Van Acker R, Wouters M, Traversari S, Steenackers M, Neukermans J, Van Breusegem F, Déjardin A, Pilate G, and Boerjan W
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- Alcohol Oxidoreductases, Biomass, Lignin, Populus genetics
- Abstract
Lignin is one of the main factors causing lignocellulosic biomass recalcitrance to enzymatic hydrolysis. Glasshouse-grown poplars severely downregulated for CINNAMYL ALCOHOL DEHYDROGENASE 1 (CAD1), the enzyme catalysing the last step in the monolignol-specific branch of lignin biosynthesis, have increased saccharification yields and normal growth. Here, we assess the performance of these hpCAD poplars in the field under short rotation coppice culture for two consecutive rotations of 1 yr and 3 yr. While 1-yr-old hpCAD wood had 10% less lignin, 3-yr-old hpCAD wood had wild-type lignin levels. Because of their altered cell wall composition, including elevated levels of cinnamaldehydes, both 1-yr-old and 3-yr-old hpCAD wood showed enhanced saccharification yields upon harsh alkaline pretreatments (up to +85% and +77%, respectively). In contrast with previous field trials with poplars less severely downregulated for CINNAMYL ALCOHOL DEHYDROGENASE (CAD), the hpCAD poplars displayed leaning phenotypes, early bud set, early flowering and yield penalties. Moreover, hpCAD wood had enlarged vessels, decreased wood density and reduced relative and free water contents. Our data show that the phenotypes of CAD-deficient poplars are strongly dependent on the environment and underpin the importance of field trials in translating basic research towards applications., (© 2022 The Authors. New Phytologist © 2022 New Phytologist Foundation.)
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- 2022
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28. Canditate metabolites for ash dieback tolerance in Fraxinus excelsior.
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Nemesio-Gorriz M, Menezes RC, Paetz C, Hammerbacher A, Steenackers M, Schamp K, Höfte M, Svatoš A, Gershenzon J, and Douglas GC
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- Europe, Plant Diseases, Ascomycota, Fraxinus genetics
- Abstract
Ash dieback, a forest epidemic caused by the invasive fungus Hymenoscyphus fraxineus, threatens ash trees throughout Europe. Within Fraxinus excelsior populations, a small proportion of genotypes show a low susceptibility to the pathogen. We compared the metabolomes from a cohort of low-susceptibility ash genotypes with a cohort of high-susceptibility ash genotypes. This revealed two significantly different chemotypes. A total of 64 candidate metabolites associated with reduced or increased susceptibility in the chemical families secoiridoids, coumarins, flavonoids, phenylethanoids, and lignans. Increased levels of two coumarins, fraxetin and esculetin, were strongly associated with reduced susceptibility to ash dieback. Both coumarins inhibited the growth of H. fraxineus in vitro when supplied at physiological concentrations, thereby validating their role as markers for low susceptibility to ash dieback. Similarly, fungal growth inhibition was observed when the methanolic bark extract of low-susceptibility ash genotypes was supplied. Our findings indicate the presence of constitutive chemical defense barriers against ash dieback in ash., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2020
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29. Transgenerational effects in asexually reproduced offspring of Populus.
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Dewan S, De Frenne P, Vanden Broeck A, Steenackers M, Vander Mijnsbrugge K, and Verheyen K
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- Amplified Fragment Length Polymorphism Analysis, Climate Change, DNA Methylation, Genome, Plant, Genotype, Photoperiod, Reproduction, Reproduction, Asexual, Seasons, Temperature, Adaptation, Biological, Epigenomics, Populus physiology
- Abstract
The response of trees to a changing climate can be affected by transgenerational phenotypic plasticity, i.e. phenotypic variation that is conserved and transferred to the offspring. Transgenerational plasticity that is influenced by epigenetics (heritable changes in gene function that do not result from changes in DNA sequence) during both sexual and asexual reproduction are of major relevance for adaptation of plants to climate change. To understand the transgenerational effects on the responses of vegetatively propagated poplar (Populus deltoides and P. trichocarpa) ramets (cuttings) to a changing environment, we tested whether the temperature and photoperiod experienced by the mother trees (genets) persistently affects the phenology of the cuttings grown in a common environment. We weekly monitored the bud phenology of the cuttings collected from the parent trees that have been growing across Europe along a >2100 km latitudinal gradient for at least 18 years. In addition, we asked whether there was variation in DNA methylation as measured by Methylation Sensitive Amplified Fragment Length Polymorphism (MSAPs) in the clones due to the different environmental conditions experienced by the parent trees. Our results indicate a transgenerational effect on bud phenology in the asexually reproduced offspring (vegetative cuttings). The temperatures experienced by the parent tree clones (from different geographic regions) altered the bud flush of the cuttings in the common garden. However, no significant epigenetic variation was detected in the cuttings of the parent trees within single genotypes growing under different climates. In sum, our results show that trees have the potential to respond to rapid climate change but the mechanism behind these changes needs to be further investigated by more powerful molecular methods like whole-genome bisulphite sequencing techniques., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2018
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30. Variability in DNA Methylation and Generational Plasticity in the Lombardy Poplar, a Single Genotype Worldwide Distributed Since the Eighteenth Century.
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Vanden Broeck A, Cox K, Brys R, Castiglione S, Cicatelli A, Guarino F, Heinze B, Steenackers M, and Vander Mijnsbrugge K
- Abstract
In the absence of genetic diversity, plants rely on the capacity of phenotypic plasticity to cope with shifts in environmental conditions. Understanding the mechanisms behind phenotypic plasticity and how local phenotypic adjustments are transferred to clonal offspring, will provide insight into its ecological and evolutionary significance. Epigenetic changes have recently been proposed to play a crucial role in rapid environmental adaptation. While the contribution of epigenetic changes to phenotypic plasticity has been extensively studied in sexual reproducing model organisms, little work has been done on vegetative generations of asexual reproducing plant species. We studied the variability of DNA methylation and bud set phenology of the Lombardy poplar ( Populus nigra cv. Italica Duroi), a cultivated tree representing a single genotype worldwide distributed since the eighteenth century. Bud set observations and CpG methyl polymorphisms were studied on vegetative offspring resulting from cuttings grown for one season in a common glasshouse environment. The cuttings were collected from 60 adult Lombardy poplars growing in different environments. The physiological condition of the cuttings was determined by measuring weight and nutrient condition. Methylation sensitive amplified polymorphisms were used to obtain global patterns of DNA methylation. Using logistic regression models, we investigated correlations among epigenotype, bud phenology, and the climate at the home site of the donor trees, while accounting for physiological effects. We found significant epigenetic variation as well as significant variation in bud phenology, in the absence of genetic variation. Remarkably, phenology of bud set observed at the end of the growing season in the common environment was significantly correlated with climate variables at the home site of the mother trees, specifically the average temperature of January and monthly potential evapotranspiration. Although we could not directly detect significant effects of epigenetic variation on phenology, our results suggest that, in the Lombardy poplar, epigenetic marks contribute to the variation of phenotypic response that can be transferred onto asexually reproduced offspring resulting in locally adapted ecotypes. This contributes to the growing evidence that epigenetic-based transgenerational inheritance might be relevant for adaptation and evolution in contrasting or rapidly changing environments.
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- 2018
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31. Variance, Genetic Control, and Spatial Phenotypic Plasticity of Morphological and Phenological Traits in Prunus spinosa and Its Large Fruited Forms ( P. x fruticans ).
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Vander Mijnsbrugge K, Turcsán A, Depypere L, and Steenackers M
- Abstract
Prunus spinosa is a highly esteemed shrub in forest and landscape plantings. Shrubs with larger organs occur often and are considered either as large fruited forms of P. spinosa or as P. x fruticans , involving a hybridization process with the ancient cultivated P. insititia (crop-to-wild gene flow). As climate change may augment hybridization processes in the future, a hybrid origin is important to detect. In addition, studying crop-to-wild gene flow can give insights in putative consequences for the wild populations. We studied the P. spinosa - P. x fruticans group, focusing on morphology and phenology in three experimental plantations. Two plantings harbored cuttings of P. spinosa (clone plantations). A third plantation comprised of a half-sib offspring from a population with both P. spinosa and P. x fruticans (family plantation). Several results point to a hybridization process as the origin of P. x fruticans . The clone plantation revealed endocarp traits to be more genetically controlled than fruit size, while this was the opposite in the family plantation, suggesting the control of fruit size being derived from the putative P. insititia parent. Bud burst, flower opening, and leaf fall were genetically controlled in the clone plantation, whereas in the family plantation intrafamily variability was remarkably large for the bud burst and leaf fall, but not for the flower opening. This suggests there is a reduced genetic control for the first two phenophases, possibly caused by historic hybridization events. Pubescence on the long shoot leaves in the family plantation deviated from the short shoot leaves on the same plants and from long and short shoot leaves in the clone plantation, suggesting again a P. insititia origin. Finally, we quantified spatial phenotypic plasticity, indicating how P. spinosa may react in a changing environment. In contrast to the bud burst and leaf fall, flower opening did not demonstrate plasticity. The fruit size was diminished at the growth site with the shortest growing season while interestingly, the leaf width was enlarged. Leaf size traits appeared more plastic on the long shoots compared to the short shoots, although partitioning of variance did not display a lesser genetic control.
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- 2016
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32. Adaptive mechanisms and genomic plasticity for drought tolerance identified in European black poplar (Populus nigra L.).
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Viger M, Smith HK, Cohen D, Dewoody J, Trewin H, Steenackers M, Bastien C, and Taylor G
- Subjects
- Biomass, Down-Regulation, France, Gene Expression, Gene Expression Regulation, Plant, Genome, Plant, Italy, Plant Leaves growth & development, Plant Stomata, Plant Transpiration, Populus growth & development, Spain, Stress, Physiological, Trees, Adaptation, Physiological, Droughts, Genes, Plant, Genotype, Phenotype, Populus genetics, Water
- Abstract
Summer droughts are likely to increase in frequency and intensity across Europe, yet long-lived trees may have a limited ability to tolerate drought. It is therefore critical that we improve our understanding of phenotypic plasticity to drought in natural populations for ecologically and economically important trees such as Populus nigra L. A common garden experiment was conducted using ∼500 wild P. nigra trees, collected from 11 river populations across Europe. Phenotypic variation was found across the collection, with southern genotypes from Spain and France characterized by small leaves and limited biomass production. To examine the relationship between phenotypic variation and drought tolerance, six genotypes with contrasting leaf morphologies were subjected to a water deficit experiment. 'North eastern' genotypes were collected at wet sites and responded to water deficit with reduced biomass growth, slow stomatal closure and reduced water use efficiency (WUE) assessed by Δ(13)C. In contrast, 'southern' genotypes originating from arid sites showed rapid stomatal closure, improved WUE and limited leaf loss. Transcriptome analyses of a genotype from Spain (Sp2, originating from an arid site) and another from northern Italy (Ita, originating from a wet site) revealed dramatic differences in gene expression response to water deficit. Transcripts controlling leaf development and stomatal patterning, including SPCH, ANT, ER, AS1, AS2, PHB, CLV1, ERL1-3 and TMM, were down-regulated in Ita but not in Sp2 in response to drought., (© The Author 2016. Published by Oxford University Press.)
- Published
- 2016
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33. Repeated Summer Drought and Re-watering during the First Growing Year of Oak (Quercus petraea) Delay Autumn Senescence and Bud Burst in the Following Spring.
- Author
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Vander Mijnsbrugge K, Turcsán A, Maes J, Duchêne N, Meeus S, Steppe K, and Steenackers M
- Abstract
Climate change predicts harsher summer droughts for mid-latitudes in Europe. To enhance our understanding of the putative impacts on forest regeneration, we studied the response of oak seedlings (Quercus petraea) to water deficit. Potted seedlings originating from three locally sourced provenances were subjected to two successive drought periods during the first growing season each followed by a plentiful re-watering. Here, we describe survival and phenological responses after the second drought treatment, applying general linear mixed modeling. From the 441 drought treated seedlings 189 subsisted with higher chances of survival among smaller plants and among single plants per pot compared to doubles. Remarkably, survival was independent of the provenance, although relatively more plants had died off in two provenances compared to the third one with mean plant height being higher in one provenance and standard deviation of plant height being higher in the other. Timing of leaf senescence was clearly delayed after the severe drought treatment followed by re-watering, with two seedlings per pot showing a lesser retardation compared to single plants. This delay can be interpreted as a compensation time in which plants recover before entering the subsequent developmental process of leaf senescence, although it renders seedlings more vulnerable to early autumn frosts because of the delayed hardening of the shoots. Onset of bud flush in the subsequent spring still showed a significant but small delay in the drought treated group, independent of the number of seedlings per pot, and can be considered as an after effect of the delayed senescence. In both phenological models significant differences among the three provenances were detected independent from the treatment. The only provenance that is believed to be local of origin, displayed the earliest leaf senescence and the latest flushing, suggesting an adaptation to the local maritime climate. This provenance also displayed the highest standard deviation of plant height, which can be interpreted as an adaptation to variable and unpredictable weather conditions, favoring smaller plants in drought-prone summers and higher plants in more normal growing seasons.
- Published
- 2016
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34. Polymer brushes on graphene.
- Author
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Steenackers M, Gigler AM, Zhang N, Deubel F, Seifert M, Hess LH, Lim CH, Loh KP, Garrido JA, Jordan R, Stutzmann M, and Sharp ID
- Subjects
- Copper chemistry, Microscopy, Atomic Force, Surface Properties, Graphite chemistry, Photochemical Processes, Polymerization, Styrene chemistry
- Abstract
A critical bottleneck for the widespread use of single layer graphene is the absence of a facile method of chemical modification which does not diminish the outstanding properties of the two-dimensional sp(2) network. Here, we report on the direct chemical modification of graphene by photopolymerization with styrene. We demonstrate that photopolymerization occurs at existing defect sites and that there is no detectable disruption of the basal plane conjugation of graphene. This method thus offers a route to define graphene functionality without degrading its electronic properties. Furthermore, we show that photopolymerization with styrene results in self-organized intercalative growth and delamination of few layer graphene. Under these reaction conditions, we find that a range of other vinyl monomers exhibits no reactivity with graphene. However, we demonstrate an alternative route by which the surface reactivity can be precisely tuned, and these monomers can be locally grafted via electron-beam-induced carbon deposition on the graphene surface.
- Published
- 2011
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35. Patterned polymer carpets.
- Author
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Amin I, Steenackers M, Zhang N, Schubel R, Beyer A, Gölzhäuser A, and Jordan R
- Subjects
- Microscopy, Atomic Force, Nanostructures chemistry, Nanostructures ultrastructure, Nanotechnology, Polyvinyls chemistry, Surface Properties, Polymers chemistry
- Abstract
For the development of polymer carpets as active devices for micro- and nanotechnology, a control of the polymer carpet morphology and especially control of the stimulus responsive polymer brush is needed. Here, we report on the first example for the fabrication of patterned polymer carpets. On a two-dimensional framework of fully crosslinked and chemically patterned nanosheets, polymer brushes of styrene and 4-vinyl pyridine were grafted by self-initiated surface photopolymerization and photografting (SIPGP). It was found that polymer grafting by SIPGP occurred over the entire nanosheets but with a preferred grafting on the amino functionalized nanosheet areas. This results in continuous polymer carpets with an intact nanosheet framework but with amplification of the chemical patterning into a three dimensional topography of the grafted polymer brush. In the case of negative patterned nanosheets, the patterned carpet could be prepared as freestanding ultrathin membranes. Furthermore, swelling experiments with poly(4-vinyl pyridine) carpets showed that the patterns induces a directional buckling of the flexible polymer carpet. This may open the possibility of the development of micro- or nanoactuator devices with anisotropic responds upon environmental changes., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2011
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36. Bud set in poplar--genetic dissection of a complex trait in natural and hybrid populations.
- Author
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Rohde A, Storme V, Jorge V, Gaudet M, Vitacolonna N, Fabbrini F, Ruttink T, Zaina G, Marron N, Dillen S, Steenackers M, Sabatti M, Morgante M, Boerjan W, and Bastien C
- Subjects
- Genetic Variation, Genome, Plant, Hybridization, Genetic, Phenotype, Populus growth & development, Principal Component Analysis, Quantitative Trait Loci, Seasons, Populus genetics
- Abstract
• The seasonal timing of growth events is crucial to tree distribution and conservation. The seasonal growth cycle is strongly adapted to the local climate that is changing because of global warming. We studied bud set as one cornerstone of the seasonal growth cycle in an integrative approach. • Bud set was dissected at the phenotypic level into several components, and phenotypic components with most genetic variation were identified. While phenotypic variation resided in the timing of growth cessation, and even so more in the duration from growth cessation to bud set, the timing of growth cessation had a stronger genetic component in both natural and hybrid populations. • Quantitative trait loci (QTL) were identified for the most discriminative phenotypic bud-set components across four poplar pedigrees. The QTL from different pedigrees were recurrently detected in six regions of the poplar genome. • These regions of 1.83-4.25 Mbp in size, containing between 202 and 394 genes, form the basis for further molecular-genetic dissection of bud set., (© The Authors (2010). Journal compilation © New Phytologist Trust (2010).)
- Published
- 2011
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37. Polymer carpets.
- Author
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Amin I, Steenackers M, Zhang N, Beyer A, Zhang X, Pirzer T, Hugel T, Jordan R, and Gölzhäuser A
- Subjects
- Microscopy, Atomic Force, Nanostructures ultrastructure, Nanotechnology, Nanostructures chemistry, Polymers chemistry
- Abstract
The fabrication of defined polymer objects of reduced dimensions such as polymer-coated nanoparticles (zero-dimensional (0D)), cylindrical brushes (1D), and polymer membranes (2D), is currently the subject of intense research. In particular, ultrathin polymer membranes with high aspect ratios are being discussed as novel materials for miniaturized sensors because they would provide extraordinary sensitivity and dynamic range when sufficient mechanical stability can be combined with flexibility and chemical functionality. Unlike current approaches that rely on crosslinking of polymer layers for stabilization, this report presents the preparation of a new class of polymer material, so-called "polymer carpets," a freestanding polymer brush grown by surface-initiated polymerization on a crosslinked 1-nm-thick monolayer. The solid-supported, as well as freestanding, polymer carpets are found to be mechanically robust and to react instantaneously and reversibly to external stimuli by buckling. The carpet mechanics and the dramatic changes of the film properties (optical, wetting) upon chemical stimuli are investigated in detail as they allow the development of completely new integrated micro-/nanotechnology devices.
- Published
- 2010
- Full Text
- View/download PDF
38. Microstructured poly(2-oxazoline) bottle-brush brushes on nanocrystalline diamond.
- Author
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Hutter NA, Reitinger A, Zhang N, Steenackers M, Williams OA, Garrido JA, and Jordan R
- Abstract
We report on the preparation of microstructured poly(2-oxazoline) bottle-brush brushes (BBBs) on nanocrystalline diamond (NCD). Structuring of NCD was performed by photolithography and plasma treatment to result in a patterned NCD surface with oxidized and hydrogenated areas. Self-initiated photografting and photopolymerization (SIPGP) of 2-isopropenyl-2-oxazoline (IPOx) resulted in selective grafting of poly(2-isopropenyl-2-oxazoline) (PIPOx) polymer brushes only at the oxidized NCD areas. Structured PIPOx brushes were converted by methyl triflate into the polyelectrolyte brush macroinitiator for the living cationic ring-opening polymerization (LCROP) of 2-oxazolines. The LCROP was performed with 2-ethyl-2-oxazoline (EtOx) as well as 2-(carbazolyl)ethyl-2-oxazoline (CarbOx) as monomers, resulting in structured bottle-brush brushes (BBB) with different pendant side chains and functionalities. FT-IR spectroscopy, fluorescence microscopy, and AFM measurements indicated a high side chain grafting density as well as quantitative and selective reactions. Poly(2-oxazoline) BBBs containing hole conducting carbazole moieties on NCD as electrode material may open the way to advanced amperometric biosensing systems.
- Published
- 2010
- Full Text
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39. Structured and gradient polymer brushes from biphenylthiol self-assembled monolayers by self-initiated photografting and photopolymerization (SIPGP).
- Author
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Steenackers M, Küller A, Stoycheva S, Grunze M, and Jordan R
- Abstract
The self-initiated photografting and photopolymerization (SIPGP) of styrene, methyl methacrylate, and tert-butyl methacrylate on structured self-assembled monolayers (SAMs) of electron beam cross-linked omega-functionalized biphenylthiols SAMs on gold was investigated. Polymer brushes with defined thickness can be prepared on crosslinked benzyl-, phenyl-, hydroxyl-, and amino-functionalized SAMs, whereas non-cross-linked SAM regions desorb from the surface during the SIPGP process. By the preparation of brush gradients on different functionalized SAMs, it was demonstrated that the resulting polymer brush layer thickness is determined by the locally applied electron beam dosage. Defined micro-nanostructured polymer brush patterns can be prepared down to a size of 50 nm. Finally, it was shown that polymer brushes obtained by the SIPGP process have a branched architecture.
- Published
- 2009
- Full Text
- View/download PDF
40. Structured polymer grafts on diamond.
- Author
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Steenackers M, Lud SQ, Niedermeier M, Bruno P, Gruen DM, Feulner P, Stutzmann M, Garrido JA, and Jordan R
- Subjects
- Crystallization, Microscopy, Atomic Force, Molecular Structure, Surface Properties, Diamond chemistry, Polymers chemistry
- Abstract
In this work, a facile method for the preparation of structured and functional polymer grafts on diamond surfaces is described. Uniform poly(styrene) (PS) grafts with a thickness of approximately 110 nm were created directly onto oxidized ultrananocrystalline diamond (UNCD) surfaces by the self-initiated photografting and photopolymerization of bulk styrene with UV irradiation. The stable covalent bonding of the PS grafts allows polymer analogue reactions with drastic reaction conditions without noticeable detachment of the polymer coating. Thus, various functionalities, such as nitro, sulfonic, and aminomethyl groups have been successfully incorporated to the polymer grafts. Furthermore, the reactivity contrast between hydrogenated and oxidized UNCD surfaces allows for the preparation of structured polymer grafts. Finally, we have demonstrated the good reactivity and accessibility of the incorporated pendant functional groups.
- Published
- 2007
- Full Text
- View/download PDF
41. Morphology control of structured polymer brushes.
- Author
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Steenackers M, Küller A, Ballav N, Zharnikov M, Grunze M, and Jordan R
- Subjects
- Electrons, Microscopy, Atomic Force, Polystyrenes chemistry, Nanostructures chemistry, Polymers chemistry
- Abstract
The surface-initiated photopolymerization (SIPP) of vinyl monomers on structured self-assembled monolayers, as defined by two-dimensional (2D) initiator templates for polymer growth, is investigated. The 2D templates are prepared by electron-beam chemical lithography (EBCL) of 4'-nitro-4-mercaptobiphenyl (NBT) and chemical conversion to an asymmetric azo initiator (4'-azomethylmalonodinitrile-1,1'-biphenyl-4-thiol). Ex situ kinetic studies of the SIPP process reveal a linear increase in the thickness of the polymer layer with the irradiation/polymerization time. The effect of the applied electron dosage during the EBCL process upon the final thickness of the polymer layer is also studied. The correlation between the electron-induced conversion of the 4'-nitro to the 4'-amino group and the layer thickness of the resulting polymer brush indicates that the polymer-brush grafting density can be directly controlled by the EBCL process. NBT-based template arrays are used for the combinatorial study of the influence of the lateral structure size and the irradiation dosage on the morphology of the resulting polymer-brush layer. Analysis of the array topography reveals the dependence of the thickness of the dry polymer layer on both electron dosage and structure size. This unique combination of EBCL as a lithographic technique to locally manipulate the surface chemistry and SIPP to amplify the created differences allows the preparation of defined polymer-brush layers of controlled morphologies.
- Published
- 2007
- Full Text
- View/download PDF
42. Nanostructured polymer brushes.
- Author
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Schmelmer U, Paul A, Küller A, Steenackers M, Ulman A, Grunze M, Gölzhäuser A, and Jordan R
- Subjects
- Macromolecular Substances chemistry, Materials Testing, Molecular Conformation, Particle Size, Surface Properties, Crystallization methods, Nanostructures chemistry, Nanostructures ultrastructure, Nanotechnology methods, Polystyrenes chemistry
- Abstract
Nanopatterned polymer brushes with sub-50-nm resolution were prepared by a combination of electron-beam chemical lithography (EBCL) of self-assembled monolayers (SAMs) and surface-initiated photopolymerization (SIPP). As a further development of our previous work, selective EBCL was performed with a highly focused electron beam and not via a mask, to region-selectively convert a SAM of 4'-nitro-1,1'-biphenyl-4-thiol to defined areas of crosslinked 4'-amino-1,1'-biphenyl-4-thiol. These "written" structures were then used to prepare surface-bonded, asymmetric, azo initiator sites of 4'-azomethylmalonodinitrile-1,1'-biphenyl-4-thiol. In the presence of bulk styrene, SIPP amplified the primary structures of line widths from 500 to 10 nm to polystyrene structures of line widths 530 nm down to approximately 45 nm at a brush height of 10 or 7 nm, respectively, as measured by scanning electron microscopy and atomic force microscopy (AFM). The relative position of individual structures was within a tolerance of a few nanometers, as verified by AFM. At line-to-line spacings down to 50-70 nm, individual polymer brush structures are still observable. Below this threshold, neighboring structures merge due to chain overlap.
- Published
- 2007
- Full Text
- View/download PDF
43. Chemical grafting of biphenyl self-assembled monolayers on ultrananocrystalline diamond.
- Author
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Lud SQ, Steenackers M, Jordan R, Bruno P, Gruen DM, Feulner P, Garrido JA, and Stutzmann M
- Abstract
We have investigated the formation of self-assembled monolayers (SAMs) of 4'-nitro-1,1-biphenyl-4-diazonium tetrafluoroborate (NBD) onto ultrananocrystalline diamond (UNCD) thin films. In contrast to the common approach to modify diamond and diamond-like substrates by electrografting, the SAM was formed from the saturated solution of NBD in acetonitrile by pure chemical grafting. Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), and near edge X-ray absorption fine structure spectroscopy (NEXAFS) have been used to verify the direct covalent attachment of the 4'-nitro-1,1-biphenyl (NB) SAM on the diamond substrate via stable C-C bonds and to estimate the monolayer packing density. The results confirm the presence of a very stable, homogeneous and dense monolayer. Additionally, the terminal nitro group of the NB SAM can be readily converted into an amino group by X-ray irradiation as well as electrochemistry. This opens the possibility of in situ electrochemical modification as well as the creation of chemical patterns (chemical lithography) in the SAM on UNCD substrates and enables a variety of consecutive chemical functionalization for sensing and molecular electronics applications.
- Published
- 2006
- Full Text
- View/download PDF
44. Genetical metabolomics of flavonoid biosynthesis in Populus: a case study.
- Author
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Morreel K, Goeminne G, Storme V, Sterck L, Ralph J, Coppieters W, Breyne P, Steenackers M, Georges M, Messens E, and Boerjan W
- Subjects
- Chromatography, High Pressure Liquid methods, Chromosome Mapping methods, Computational Biology methods, Flavonoids chemistry, Flavonoids genetics, Genes, Plant, Lod Score, Populus chemistry, Flavonoids biosynthesis, Populus genetics, Populus metabolism, Quantitative Trait Loci
- Abstract
Genetical metabolomics [metabolite profiling combined with quantitative trait locus (QTL) analysis] has been proposed as a new tool to identify loci that control metabolite abundances. This concept was evaluated in a case study with the model tree Populus. Using HPLC, the peak abundances were analyzed of 15 closely related flavonoids present in apical tissues of two full-sib poplar families, Populus deltoides cv. S9-2 x P. nigra cv. Ghoy and P. deltoides cv. S9-2 x P. trichocarpa cv. V24, and correlation and QTL analysis were used to detect flux control points in flavonoid biosynthesis. Four robust metabolite quantitative trait loci (mQTL), associated with rate-limiting steps in flavonoid biosynthesis, were mapped. Each mQTL was involved in the flux control to one or two flavonoids. Based on the identities of the affected metabolites and the flavonoid pathway structure, a tentative function was assigned to three of these mQTL, and the corresponding candidate genes were mapped. The data indicate that the combination of metabolite profiling with QTL analysis is a valuable tool to identify control points in a complex metabolic pathway of closely related compounds.
- Published
- 2006
- Full Text
- View/download PDF
45. Identification of genes involved in vertical rust resistance in poplar.
- Author
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Maertens I, Breyne P, Steenackers M, and Gheysen G
- Subjects
- Crosses, Genetic, Genetic Variation, Plant Diseases, Populus growth & development, Immunity, Innate genetics, Populus genetics
- Published
- 2004
46. Phylogenetic position of phytopathogens within the Enterobacteriaceae.
- Author
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Hauben L, Moore ER, Vauterin L, Steenackers M, Mergaert J, Verdonck L, and Swings J
- Subjects
- Bacterial Typing Techniques, Base Composition, Base Sequence, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal chemistry, DNA, Ribosomal genetics, Molecular Sequence Data, RNA, Bacterial genetics, RNA, Ribosomal, 16S genetics, Species Specificity, Enterobacteriaceae classification, Enterobacteriaceae genetics, Phylogeny, Plant Diseases microbiology
- Abstract
The almost complete 16S rDNA sequences of twenty nine plant-associated strains, representing species of the genera Erwinia, Pantoea and Enterobacter were determined and compared with those of other members of the Enterobacteriaceae. The species of the genus Erwinia may be divided into three phylogenetic groups. Cluster I represents the true erwinias and comprises E. amylovora, E. mallotivora, E. persicinus, E. psidii, E. rhapontici and E. tracheiphila. We propose to unite the species of cluster II, E. carotovora subsp. atroseptica, E. carotovora subsp. betavasculorum, E. carotovora subsp. carotovora, E. carotovora subsp. odorifera, E. carotovora subsp. wasabiae, E. cacticida, E. chrysanthemi and E. cypripedii in the genus Pectobacterium respectively as P. carotovorum subsp. atrosepticum comb. nov., P. carotovorum subsp. betavasculorum comb. nov., P. carotovorum subsp. carotovorum comb. nov., P. carotovorum subsp. odoriferum comb. nov., P. carotovorum subsp. wasabiae comb. nov., P. cacticidum comb. nov., P. chrysanthemi and P. cypripedii. The species E. alni, E. nigrifluens, E. paradisiaca, E. quercina, E. rubrifaciens and E. salicis, comprising cluster III, are being classified into a new genus Brenneria gen. nov. respectively as B. alni comb. nov., B. nigrifluens comb. nov., B. paradisiaca comb. nov., B. quercina comb. nov., B. rubrifaciens comb. nov. and B. salicis comb. nov. The species of the genus Pantoea, included in this study, form a monophyletic unit (cluster IV), closely related with Erwinia, whereas the three phytopathogenic species of the genus Enterobacter are scattered among the genera Citrobacter and Klebsiella.
- Published
- 1998
- Full Text
- View/download PDF
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