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Bioenergy will be one of the most important renewable energy sources in the conversion from fossil fuels to bio-based products. Short rotation coppice Salix could be a key player in this conversion since Salix has rapid growth, positive energy balance, easy to manage cultivation system with vegetative propagation of plant material and multiple harvests from the same plantation. The aim of the present paper is to provide an overview of the main challenges and key issues in willow genetic improvement toward sustainable biofuel value chains. Primarily based on results from the research project "Optimized Utilization of Salix" (OPTUS), the influence of Salix wood quality on the potential for biofuel use is discussed, followed by issues related to the conversion of Salix biomass into liquid and gaseous transportation fuels. Thereafter, the studies address genotypic influence on soil carbon sequestration in Salix plantations, as well as on soil carbon dynamics and climate change impacts. Finally, the opportunities for plant breeding are discussed using willow as a resource for sustainable biofuel production. Substantial phenotypic and genotypic variation was reported for different wood quality traits important in biological (i.e., enzymatic and anaerobic) and thermochemical conversion processes, which is a prerequisite for plant breeding. Furthermore, different Salix genotypes can affect soil carbon sequestration variably, and life cycle assessment illustrates that these differences can result in different climate mitigation potential depending on genotype. Thus, the potential of Salix plantations for sustainable biomass production and its conversion into biofuels is shown. Large genetic variation in various wood and biomass traits, important for different conversion processes and carbon sequestration, provides opportunities to enhance the sustainability of the production system via plant breeding. This includes new breeding targets in addition to traditional targets for high yield to improve biomass quality and carbon sequestration potential.

Cerebral cavernous malformation (CCM) is a neurovascular disease that results in various neurological symptoms. Thrombi have been reported in surgically resected CCM patient biopsies, but the molecular signatures of these thrombi remain elusive. Here, we investigated the kinetics of thrombi formation in CCM and how thrombi affect the vasculature and contribute to cerebral hypoxia. We used RNA sequencing to investigate the transcriptome of mouse brain endothelial cells with an inducible endothelial-specific Ccm3 knock-out (Ccm3-iECKO). We found that Ccm3-deficient brain endothelial cells had a higher expression of genes related to the coagulation cascade and hypoxia when compared with wild-type brain endothelial cells. Immunofluorescent assays identified key molecular signatures of thrombi such as fibrin, von Willebrand factor, and activated platelets in Ccm3-iECKO mice and human CCM biopsies. Notably, we identified polyhedrocytes in Ccm3-iECKO mice and human CCM biopsies and report it for the first time. We also found that the parenchyma surrounding CCM lesions is hypoxic and that more thrombi correlate with higher levels of hypoxia. We created an in vitro model to study CCM pathology and found that human brain endothelial cells deficient for CCM3 expressed elevated levels of plasminogen activator inhibitor-1 and had a redistribution of von Willebrand factor. With transcriptomics, comprehensive imaging, and an in vitro CCM preclinical model, this study provides experimental evidence that genes and proteins related to the coagulation cascade affect the brain vasculature and promote neurological side effects such as hypoxia in CCMs. This study supports the concept that antithrombotic therapy may be beneficial for patients with CCM.

A host of physical and environmental factors may influence fungal decay including the wood substrate, temperature, moisture, oxygen, light, pH, and nitrogen. Understanding the effects of these factors on fungal decay is important for the effective utilization of wood decay fungi in biotechnological processes and for understanding the role of these organisms in global carbon cycling. The ascomycete Xylaria hypoxylon causes white rot of hardwoods, but remains relatively under-characterized. In this investigation, the decay capability of this fungus was studied using beech, hornbeam, oak and pine. Although Xylaria species are considered as causing white rot decay, Type II soft rot erosion was observed on hornbeam, Type I soft rot cavities were noted on beech, simultaneous rot was found on oak and selective rot on pine. Results indicated that both wood species and cell wall chemistry affected morphological decay patterns illustrating the relationships between fungal enzymatic capacity and wood cell wall structure/chemistry.

Salix (willow) is a well-known coppice plant that has been used as a source for bioenergy for decades. With recent developments in changing from a fossil-based to a circular bioeconomy, greater interest has been orientated towards willow as a potential source of biomass for transport biofuels. This has created increasing interest for breeding strategies to produce interesting genotypic and phenotypic traits in different willow varieties. In the present study, 326 genetically distinct clones and several commercial varieties of S. viminalis were analyzed using complementary approaches including density, chemical, image, histochemical, and morphometric analyses. A systematic approach was adopted whereby the basal regions of harvested stems were separated and used in all studies to aid comparisons. Density analyses were performed on all clone individuals, and from the results, 20 individual plants representing 19 clones were selected for the more in-depth analyses (chemical, image analysis, histochemical, and morphometric). The absolute dry density of the clones selected varied between ca. 300 and 660 kg/m3 with less variation seen in the commercial S. viminalis varieties (ca. 450–520 kg/m3). Selected clones for chemical analysis showed the largest variation in glucose (47.3–60.1%; i.e., cellulose) and total sugar content, which ranged between ca. 61 and 77% and only ca. 16 and 22% for lignin. Image analyses of entire basal stem sections showed presence of tension wood in variable amounts (ca. 7–39%) with characteristic G-fibers containing cellulose-rich and non-lignified gelatinous layers. Several of the clones showing prominent tension wood also showed high glucose and total sugar content as well as low lignin levels. A morphometric approach using an optical fiber analyzer (OFA) for analyzing 1000 s (minimum 100,000 particles) of macerated fibers was evaluated as a convenient tool for determining the presence of tension wood in stem samples. Statistical analyses showed that for S. viminalis stems of the same density and thickness, the OFA approach could separate tension wood fibers from normal wood fibers by length but not fiber width. Results emphasized considerable variability between the clones in the physical and chemical approaches adopted, but that a common aspect for all clones was the occurrence of tension wood. Since tension wood with G-fibers and cellulose-rich G-layers represents an increased source of readily available non-recalcitrant cellulose for biofuels, S. viminalis breeding programs should be orientated towards determining factors for its enhancement.

The characterization of a radiological scene is a major issue in many fields, such as nuclear safety and security, Decommissioning & Dismantling or in the medical field. Such an analysis consists in answering two main questions. On the one hand, what radioelements are present in the scene and in what quantities? On the other hand, where are these radio-emitting sources located? The systems designed to answer these questions use the information carried by the X and gamma photons from these radioactive sources, hence the name "gamma camera" for these systems. Their performances naturally depend on those of the instrument, but also on the performances of the processing algorithms applied to the data acquired by the instrument. In the framework of this thesis, I study the development of a gamma camera, based on the Caliste technology, a CdTe detector for high-energy photons, which results from more than fifteen years of development, initially for applications in astrophysical observation. The spectrometric and imaging performances of this detector are a world reference in the field of CdTe detectors, hence the relevance of its application for gamma cameras. More specifically, my thesis work explores three axes. First, through a detailed modelling of the detector, I analyse the spectrometric data from Caliste in order to understand how they carry the information of the nature and quantity of radioelements. This modelling and this analysis allow me to develop new and original spectrometric data processing algorithms, based on deep learning methods and Bayesian convolutional neural networks, in order to answer the question of identification and quantification of radioelements while providing an estimation of the uncertainty of the results. In a second step, I study the use of coded mask imaging methods with Caliste, and in particular, the algorithms for locating radioactive sources. I show the application and the limits for the reconstruction provided by the algorithms usually used for this problem and then I demonstrate the potential of deep learning algorithms to overcome these limits. Finally, I analyse the problem of localization of radioactive hot spots by Compton imaging, through processing algorithms adapted to Caliste detectors, by comparing the performances of methods resulting from the state of the art to new methods that I develop. Throughout this thesis work, I develop my algorithms from simulation data in order to transpose these methods to other detection systems. Then, I take care to test them on data acquired with Caliste detectors, in order to obtain an evaluation of their performances, faithful to real conditions and in order to confront these algorithms with the hazards of the measurements, not taken into account in the simulations; La caractérisation d’une scène radiologique est un enjeu majeur dans de nombreux domaines, comme la sûreté et la sécurité nucléaire, les problématiques d’assainissement-démantèlement ou encore dans le domaine médical. Une telle analyse consiste à répondre à deux questions principales. D’une part, quels sont les radioéléments présents dans la scène et en quelles quantités ? D’autre part, où se situent ces sources radio-émettrices ? Les systèmes conçus pour répondre à ces questions utilisent l’information portée par les photons X et gamma issus de ces sources radioactives, d’où le nom de « caméra gamma » donné à ces systèmes. Leurs performances dépendent naturellement de celles de l’instrument utilisé, mais aussi des performances des algorithmes de traitement appliqués aux données acquises par l’instrument. Dans le cadre de cette thèse, j’étudie le développement d’un système de caméra gamma, basé sur la technologie Caliste, détecteur CdTe de photons de haute-énergie, issu de plus de quinze années de développement, initialement pour des applications en observation astrophysique. Les performances spectrométriques et en imagerie de ce détecteur sont une référence mondiale dans le domaine des détecteurs CdTe, d’où la pertinence de son application pour des caméras gamma. Plus spécifiquement, mon travail de thèse s’articule en trois axes. Dans un premier temps, à travers une modélisation détaillée du détecteur, j’analyse les données spectrométriques issues de Caliste afin de comprendre comment l’information de la nature et de la quantité des radioéléments sont inscrites dans ces données. Cette modélisation et cette analyse me permettent de mettre en place des algorithmes de traitement des données spectrométriques nouveaux et originaux, basés sur les méthodes de deep learning et de réseaux de neurones convolutifs bayésiens, dans le but de répondre à la question de l’identification et de la quantification des radioéléments tout en apportant une estimation de l’incertitude sur les résultats. Dans un second temps, j’étudie l’utilisation des méthodes d’imagerie à masque codé avec le détecteur Caliste, et en particulier, les algorithmes de localisation des sources radioactives. Je montre l’application et les limites des algorithmes de reconstruction habituellement utilisés pour cette problématique puis je démontre le potentiel des algorithmes de deep learning pour surpasser ces limites. Enfin, je m’intéresse à la problématique de la localisation de points chauds radioactifs par imagerie Compton, à travers des algorithmes de traitement adaptés au détecteur Caliste, en comparant les performances des méthodes issues de l’état de l’art à de nouvelles méthodes que je mets en place. Au long de ce travail de thèse, j’effectue les développements de mes algorithmes à partir de données issues de simulation de sorte à pouvoir transposer ces méthodes à d’autres systèmes de détection. Je prends ensuite le soin de les tester sur des données acquises avec le détecteur Caliste, afin d’obtenir une évaluation de leurs performances, fidèle aux conditions réelles et afin d’être confronté aux aléas des mesures, non pris en compte dans les simulations.

Denna rapport innehåller resultat från den fjärde besiktningen av olika trä-, plast- och kompositmaterial exponerade sedan 2013 (några material sedan 2014 och 2016) i två bryggor vid Sibbarps badplats i Malmö strax norr om Øresundsbron. Tanken med att exponera materialen i denna miljö är att relativt snabbt får besked om vilka material som ser ut att klara sig bäst och uppfylla Malmö Stads gatukontors krav på utseende, hållbarhet och funktion i en utsatt miljö. Försöket har, trots att det pågått under en förhållandevis kort tid, givit värdefull information om olika materials egenskaper och lämplighet för användning utomhus i utsatta miljöer med hänsyn till fuktpåverkan och angrepp av biologiska skadegörare, men även med hänsyn till mekaniska och utseendemässiga aspekter. Samtliga trämaterial har snabbt blivit gråa, medan plast- och kompositmaterialen ännu efter ca 77 månaders exponering i stort sett har kvar sin ursprungsfärg. Samtliga trämaterial och trä-plastkompositer har i varierande grad fått påväxt av missfärgande svamp, alger och i några fall även av lavar. Materialen av återvunnen plast har i stort sett klarat sig utan påväxt. Rötskador har efter ca 77 månader observerats på samtliga plankor impregnerade med Organowood. Huruvida rötskadorna beror på dålig impregnering med undermålig inträngning och/eller upptagning av kiselprodukt eller på dålig rötskyddseffekt eller på en kombination av de båda har inte med säkerhet kunnat fastställas. Rötskador har även observerats på plankor av Sioo-behandlad gotländsk furukärnved, där angrepp uppkommit i kvarsittande splintved, ek och robinia. Små begynnande angrepp runt skruvskallar observerades efter ca 40 månader i jättetuja (Western red cedar) och roble, möjligen orsakad av kemisk nedbrytning, s k ”nail sickness”. De mekaniska egenskaperna skiljer sig en hel del mellan materialen. Sprickbildning och uppfläkning av virkesytan, särskilt på kantsidor, kan i värsta fall orsaka skador på framför allt bara fötter. Ek och robinia har visat sig särskilt utsatta för ogynnsam sprickbildning. Samtliga trämaterial med rillad yta har också utsatts för viss sprickbildning i rillorna. För bryggor, gångdäck och altaner, där folk ofta vistas barfota avrådes därför för användning av material, inklusive rillat, som ger upphov till stor sprickbildning.

Titanium (oxo-) alkoxide phosphonate complexes were synthesized using different titanium precursors and tert-butylphosphonic acid (tBPA) as molecular models for interaction between phosphonates and titania surfaces and to investigate the solution stability of these species. Reflux of titanium(IV) ethoxide ortitanium(IV)(diisopropoxide)bis(2,4-pentadionate) withtert-butylphosphonic acid in toluene–ethanolmixture or acetone yielded seven titanium alkoxide phosphonate complexes; [Ti5(m3-O)(m2-O)-(m-HOEt)2(m-OEt)3(m2-OEt)(m3-tBPA)3(m3-HtBPA)(m2-tBPA)2(m2-HtBPA)]$3EtOH,1, [Ti4O(m-OEt)5(m2-OEt)7-(m3-tBPA)],2,[Ti4(m2-O)2(m-OEt)2(m-HOEt)2(m2-tPBA)2(m2-HtPBA)6]$4EtOH,3,[Ti4(m2-O)2(m-OEt)2(m-HOEt)2-(m2-tPBA)2(m2-HtPBA)6]$2EtOH,4,[Ti6(m2-O)(m3-O)2(m2-OEt)5(m-OEt)6(m3-tBPA)3(m3-HtBPA)],5,[Ti4(m-iOPr)4(acac)4(m2-tBPA)4],6 and [Ti5(m4-O)(m2-O)3(m2-OEt)4(m-OEt)6(m-HOEt)(m3-tBPA)]2,7. The binding mode of tBPAtothetitanium oxo-core were either double or triple bridging or a combination of the two. No monodentate or chelating coordination was observed.31P NMR spectrometry of dissolved single crystals indicates that 1 and 5 retain their solid-state structures in solution, the latter even on moderate heating, while 6 and 7 dissolved into several other forms. The complexes were found to be sensitive towards hydrolysis, proceeding in a topotacticfashion with densification of the material into plates and lamellae resulting finally in “core–shell”nanoparticles with a crystalline core (anatase) and an amorphous outer shell upon contact with water at room temperature as observed by HRTEM and AFM analyses.31P NMR data supported degradation after addition of water to solutions of the complexes. Hydrolysis under different conditions affords complex oxide structures of different morphologies.

This study evaluated the potential of biochar impregnated with Fe3+ or Ca2+, or mixed with Polonite®, as a filter material for removal of phosphate (PO4-P) from wastewater in onsite wastewater treatment systems (OWTS). Four treatments with biochar were investigated: unimpregnated biochar (UBC), biochar impregnated with iron Fe3+ (FBC), biochar impregnated with calcium oxide (CBC), and biochar mixed with Polonite® (PBC). In a batch experiment using phosphate solution at concentrations 0.5, 3.3, 6.5, 13, and 26 mg PO4-P L–1, adsorption of PO4-P in the different treatments was modeled using Langmuir and Freundlich isotherms. Column filters (5 diameter × 55 cm height) packed with UBC, FBC, CBC, and PBC were then furnished with raw wastewater over 148 weeks. During this experiment, adsorption of PO4-P was investigated in response to increasing hydraulic loading rate (HLR; 56, 74, and 112 L m–2 day–1) and increasing phosphate loading rate (PLR; 195, 324, 653, and 1715 mg PO4-P m–2 day–1). Among the materials, FBC had the highest maximum adsorption capacity (Qm) based on Langmuir isotherms (3.21 ± 0.01 mg g–1). FBC and CBC showed robust performance with increasing HLR, while increasing PLR increased the amount of PO4-P retained in all filters. After 148 weeks of operation, removal of PO4-P (averaged over the last 18 weeks of operation) was 13 ± 16% for UBC, 40 ± 20% for CBC, 88 ± 12% for FBC, and 30 ± 18% for PBC. The PO4-P amount retained in filters over the 148 weeks was 84.75, 221.75, 358.38, and 152.36 g m–2 in UBC, CBC, FBC, and PBC, respectively. The adsorption capacity of the filters after 148 weeks was 1.50, 4.02, 6.41, and 2.75 mg g–1 for UBC, CBC, FBC, and PBC, respectively. The adsorption capacity values and breakthrough curves showed that low concentrations (i.e.