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Seismic data contain information about elastic properties and the structural patterns of the subsurface. However, before we get an image of the subsurface, seismic data goes through many processing steps that consist of applying theory of wave propagation and mathematical and statistical signal processing. In this thesis, we have investigated breakthroughs within artificial intelligence for seismic wavefield reconstruction. In the first paper, we developed a method that is suited for marine collection where one can utilize similarities between acquisition domains to train the machine learning model. In the second paper, we utilize methodology from image inpainting combined with inverse theory to fit the reconstruction problem in the offset domain, within an unsupervised deep learning framework. In the final paper, we illustrate how one can demigrate field data to generate suitable training data for interpolation and regularization of offset classes. This synthesized training data can then be used to create the prediction models. In all three papers, we have documented an improvement compared to existing "state-of-the-art" methods from the industry.

The validity of the Brink-Axel hypothesis, which is especially important for numerous astrophysical calculations, is addressed for 116,120,124Sn below the neutron separation energy by means of three independent experimental methods. The $\gamma$-ray strength functions (GSFs) extracted from primary $\gamma$-decay spectra following charged-particle reactions with the Oslo method and with the Shape method demonstrate excellent agreement with those deduced from forward-angle inelastic proton scattering at relativistic beam energies. In addition, the GSFs are shown to be independent of excitation energies and spins of the initial and final states. The results provide a critical test of the generalized Brink-Axel hypothesis in heavy nuclei, demonstrating its applicability in the energy region of the pygmy dipole resonance., Comment: 6 pages, 4 figures, Phys. Rev. Lett. (in press)

An intact and dynamic microtubule cytoskeleton is crucial for the development, differentiation, and maintenance of the mammalian cortex. Variants in a host of structural microtubulin-associated proteins have been identified to cause a wide spectrum of malformations of cortical development and alterations of microtubule dynamics have been recognized to cause or contribute to progressive neurodegenerative disorders. TBCD is one of the five tubulin-specific chaperones and is required for reversible assembly of the α-/β-tubulin heterodimer. Recently, variants in TBCD, and one other tubulin-specific chaperone, TBCE, have been identified in patients with distinct progressive encephalopathy with a seemingly broad clinical spectrum. Here, we report the clinical, neuroradiological, and neuropathological features in eight patients originating from the Faroe Islands, who presented with an early onset, progressive encephalopathy with features of primary neurodegeneration, and a homogenous clinical course. These patients were homozygous for a TBCD missense variant c.[3099C>G]; p.(Asn1033Lys), which we show has a high carrier frequency in the Faroese population (2.6%). The patients had similar age of onset as the previously reported patients (n = 24), but much shorter survival, which could be caused by either differences in supportive treatment, or alternatively, that shorter survival is intrinsic to the Faroese phenotype. We present a detailed description of the neuropathology and MR imaging characteristics of a subset of these patients, adding insight into the phenotype of TBCD-related encephalopathy. The finding of a Faroese founder variant will allow targeted genetic diagnostics in patients of Faroese descent as well as improved genetic counseling and testing of at-risk couples.

BACKGROUND: Discrimination between recurrent glioblastoma and therapy-related changes with conventional magnetic resonance imaging (MRI) is challenging. There is increasing evidence for the clinical value of positron emission tomography (PET) with O-(2-18F-fluoroethyl)-L-tyrosine (FET) in addition to MRI in cases of ambiguous findings in the setting of posttreatment care. The diagnostic accuracy, however, varies among the published studies and is influenced by the composition of the population with different glioma subtypes/grades, lack of histological confirmation, and differences in data processing. Herein, we evaluated the diagnostic accuracy of FET PET scans in glioblastoma patients. MATERIAL AND METHODS: One hundred thirty-seven consecutive patients who had undergone 150 FET PET were reviewed retrospectively. Inclusion criteria were 1) histologically-proven glioblastoma; 2) previous surgery followed by oncological treatment consisting of standard radiochemotherapy or - if at second recurrence - chemotherapy; 3) unexplained constant or increasing contrast-enhancing (CE) lesions on T1, or non-CE lesions on T2 FLAIR MRI later than 6 months after radiotherapy, where the differentiation between disease recurrence or therapy-related changes was uncertain; 4) FET PET for supplementary evaluation; 5) a histological evaluation following surgery less than 3 months after FET PET, or MRI follow-up. FET PET scans were performed as 20-minute static PET/CT acquisitions and evaluated co-registered to T1 post-contrast MRI with measurement of maximum and mean tumor-to-brain ratios (TBR(max,) TBR(mean)). Receiver operating characteristics (ROC) analysis was used to determine the optimal threshold of FET parameters. The prognostic influence of FET parameters on overall survival (OS) was investigated with the Cox proportional hazards model. RESULTS: The median time interval from radiotherapy until the radiological progression was 13 months. One hundred twenty-six PET scans demonstrated FET uptake of varying intensity. Surgical interventions were performed following 88 PET scans, while 62 PET scans were evaluated by clinical or MRI follow-up, resulting in 131 glioblastoma recurrences and 19 therapy-related changes. ROC analysis yielded the thresholds of 2.0 for TBR(max) and 1.8 for TBR(mean) for differentiation between recurrent disease and therapy-related changes with the best performance of TBR(max) with a sensitivity of 96% and a specificity of 100% (p < 0.0001). Using this threshold, 145 of 150 PET scans of glioblastoma recurrence or therapy-related changes were accurately classified. Multivariate survival analysis showed that TBR(max) > 2.0 predicted independently a shorter OS in patients, who did not undergo subsequent therapy following PET (p = 0.002). CONCLUSION: FET PET is a powerful noninvasive tool to distinguish recurrent glioblastoma from therapy-related changes.

Nervous system development is highly dependent on the function of microtubules, which are assembled from tubulin heterodimers containing several α- and β-tubulin isotypes encoded by separate genes. A spectrum of neurological disorders with malformations of the central nervous system has recently been associated with missense mutations in this group of genes. Here, we report two patients, monozygotic twins, carrying a de novo 0.32 Mb deletion of chromosome 16q24.3 including the TUBB3 gene. The patients presented with global developmental delay, mild facial dysmorphism, secondary microcephaly, and mild spastic diplegia. Cerebral magnetic resonance imaging of the patients did not reveal cortical malformations, malformations of the corticospinal tracts, basal ganglia, corpus callosum, or optic nerves. This observation is in contrast to the group of neurological disorders that are associated with heterozygous missense mutations in genes encoding different neuronal α- and β-tubulin isotypes, termed tubulinopathies. On the background of current knowledge regarding the function and genotype–phenotype correlations of mutations in the neuronal tubulin isotypes, the clinical and diagnostic findings in these patients are discussed. To our knowledge, this is the first report of patients with a de novo deletion of the TUBB3 gene. The lack of cortical or other cerebral malformations supports the current hypothesis that TUBB3-related tubulinopathies are caused by altered protein function. © 2015 Wiley Periodicals, Inc.

This paper presents the results from a series of physical modeling and three-dimensional finite 9 element (FE) analyses, which examined the uniaxial vertical capacity of suction caissons for 10 offshore wind turbines. The experiments were carried out in quartz sand and involved monotonic 11 application of vertical load. It was found that the drained capacity of suction caissons is 12 dependent on embedment ratio. On the other hand, predictions from conventional semi-empirical 13 depth factors were found to somewhat underestimate when applied to rough foundations. On the 14 basis of the tests and FE analyses, new expressions for depth factor of shallow foundations have 15 been validated for embedment ratios (aspect ratios) up to unity, calibrating the fitting parameters 16 by employing data from a range of soil profiles.

Bucket foundations, which are large cylindrical structures that are open at the base and closed at the top, recently have attracted much attention in offshore projects. To demonstrate the relationship between the vertical bearing capacity of a bucket foundation relative to the corresponding capacity of the circular plate, several loading tests on small-scale bucket and surface foundations were performed at Aalborg University. In the current research, the modified vertical bearing capacity of circular surface footings was investigated with the reduced friction angle. A linear relationship with reasonable accuracy was found between the relative density and the reduced friction angle.

The purpose of this master thesis is to develop data-driven mathematical models to “simulate” an equipment lifecycle over a period of time to reveal the associated effects like survival curve and hazard rate. The failure frequency or the hazard rate is input to a cost/benefit analysis with cost of failure and cost of maintenance to find the optimal maintenance interval. Furthermore a baseline preventive maintenance program made with Reliability Centred Maintenance methodology is compared with the PM-program optimized with use of the data-driven methodology. The model is tested and used with a sample size of 100, random sampled over a period of 10 years and uses OREDA failure mode dataset with Mean failure rates as input. Survival Analysis is developed with use of Lifelines resulting into estimated survival (reliability) function with and the Kaplan Meier estimate and estimated Hazard rate with the Nelson Aalen estimate. The study shows potentials of cost savings using data-driven modelling; however the most beneficial is that the data-driven modelling results into a decision basis for cost/benefit analysis for optimizing maintenance. Decision basis support like chance of asset survival for a given time interval, MTTF (Mean Time To Failure) and hazard rate. Last but not least recommendations for further work are discussed.

6 pages; International audience; Isomeric states in 253No have been investigated by conversion-electron and gamma-ray spectroscopy with the GABRIELA detection system. The 31 micro second isomer reported more than 30 years ago is found to decay to the ground state of 253No by the emission of a 167 keV M2 transition. The spin and parity of this low-lying isomeric state are established to be 5/2+. The presence of another longer-lived isomeric state is also discussed.

A series of comprehensive research and development projects has validated the novel concept of the bucket foundation as an alternative to piled foundations, and bucket foundations are rapidly becoming a viable option for offshore wind farms and marginal fields.Within the last decade, experimental studies have indicated the possibility of defining foundation response using plasticity theory. Results of multiple loading tests addressing the effect of embedment on the strain-hardening behavior of shallow bucket foundations under combined loading are reported. The kinematic mechanisms accompanying pre-failure are presented. It is argued that the drained capacity of offshore bucket foundations and the ratio of plastic increments are largely influenced by embedment depth and the preload ratio V/Vpeak.

In the project IRMA-EU (IRMA: integrated resonant accelerometer microsystem for automotive applications), a project sponsored by the European Commision under ESPRIT, SensoNor and project partners Autoliv and SINTEF are developing a resonant-structure two-chip accelerometer silicon microsystem for automotive applications, the SA30 Crash Sensor for front impacts, with range ± 50g. The project is focusing on the development of key process technologies, product designs and manufacture of functional prototypes. The IRMA project is coordinated with other activities performed by the partners to cover all aspects of research and technology development as well as establishment of high-volume production capabilities needed for successful product innovation of this new generation of crash sensors. The sensing principle is an acceleration-sensitive resonant structure, with an ASIC for resonance control and signal conditioning. Prototypes in silicon of both the sensor chip and the ASIC chip have confirmed the feasibility of the concept. Ramp up to high-volume production will be started as soon as fully functional microsystems are demonstrated.

A new concept with respect to offshore wind turbines, the bucket foundation, is known in the oil and gas industry, although the load conditions for wind turbines are significantly different. An extensive number of loading tests with small-scale bucket foundations subjected to combined loading were carried out in the geotechnical laboratory at Aalborg University in Aalborg, Denmark. Tests were performed on buckets of various sizes, embedment ratios, and load paths on saturated dense Aalborg University Sand No. 1. The experimental results were used to evaluate the behavior of the bucket foundations in accordance with the macromodel approach. An expression to describe the combined capacity of bucket foundations was developed by calibrating the failure criteria for bucket foundations.

Photoneutron cross sections were measured for ${}^{94}$Mo, ${}^{95}$Mo, ${}^{96}$Mo, ${}^{97}$Mo, ${}^{98}$Mo, and ${}^{100}$Mo near the neutron threshold with quasi-monochromatic laser-Compton scattering $\ensuremath{\gamma}$ rays. The photoneutron data were analyzed with the Skyrme Hartree-Fock-Bogoliubov (HFB) plus quasiparticle random phase approximation (QRPA) model and the axially symmetric-deformed Gogny HFB plus QRPA model of $E1$ $\ensuremath{\gamma}$-ray strength. Combining the $\ensuremath{\gamma}$-ray strength function constrained by the present photoneutron data with either the nuclear resonance fluorescence data or the updated Oslo data to supplement the data below the neutron threshold, a thorough analysis of the reverse $(n,\ensuremath{\gamma})$ cross sections is made whenever measurements are available. The Oslo data and the corresponding uncertainties are updated based on the latest results of the $s$-wave neutron spacing and the average radiative width determined in particular for ${}^{96}$Mo. Finally, radiative neutron capture cross sections for two radioactive nuclei, ${}^{93}$Mo and ${}^{99}$Mo, are deduced with the $\ensuremath{\gamma}$-ray strength function method.

The level densities and $\ensuremath{\gamma}$-ray strength functions of ${}^{105,106,111,112}$Cd have been extracted from particle-$\ensuremath{\gamma}$ coincidence data using the Oslo method. The level densities are in very good agreement with known levels at low excitation energy. The $\ensuremath{\gamma}$-ray strength functions display no strong enhancement for low $\ensuremath{\gamma}$ energies. However, more low-energy strength is apparent for ${}^{105,106}$Cd than for ${}^{111,112}$Cd. For $\ensuremath{\gamma}$ energies above $\ensuremath{\approx}$4 MeV, there is evidence for some extra strength, similar to what has been previously observed for the Sn isotopes. The origin of this extra strength is unclear; it might be due to $E1$ and $M1$ transitions originating from neutron skin oscillations or the spin-flip resonance, respectively.

Primary γ-ray spectra for a wide excitation-energy range have been extracted for 44Ti from particle-γ coincidence data of the 46Ti(p,tγ)44Ti reaction. These spectra reveal information on the γ-decay pattern of the nucleus and may be used to extract the level density and radiative strength function applying the Oslo method. Models of the level density and radiative strength function are used as input for cross-section calculations of the 40Ca(α,γ)44Ti reaction. Acceptable models should reproduce data on the 40Ca(α,γ)44Ti reaction cross section as well as the measured primary γ-ray spectra. This is only achieved when a coherent normalization of the slope of the level density and radiative strength function is performed. Thus, the overall shape of the experimental primary γ-ray spectra puts a constraint on the input models for the rate calculations. © 2012 American Physical Society.

AIM: Assessment of amino acid transport using PET tracers such as [18F]-fluor-ethyl-thyrosine (FET) is a valuable supplement to routine contrast enhanced structural MRI in the initial and follow up evaluations of patients with brain tumors. MRI blood volume (BV) imaging using dynamic susceptibility contrast (DSC) has also been shown to give important information about tumor angiogenesis. The aim of the study was to investigate the feasibility of simultaneous imaging of structural MRI, angiogenic activity (BV DSC), and metabolic activity (FET) in a short single session using an integrated PET/MRI scanner. METHODS AND MATERIALS: Twenty-five scans were obtained in 22 referred brain tumor patients. A 20 min static simultaneous PET/MRI (Siemens mMR) acquisition 20 min. p.i. of 200 MBq FET was performed. The MRI protocol included axial FLAIR and post-contrast T1 MPRAGE. For BV imaging the contrast agent (0.1-0.2 ml/kg, Gadovist 1 mmol/ml) was administered using a power injector and BV maps were calculated using dedicated software. Metabolically active tumor volume (FET-vol) was defined in tissue as activity > 1.6 x background activity (B), and metabolic activity, Tmax/B, as maximal tumor activity/B. A low-dose CT scan was obtained for attenuation correction. RESULTS: The PET/MRI scans were well-accepted by patients. Fourteen had high grade glioma (glioblastoma n = 9, oligodendroglioma III n = 4, astrocytoma III n = 1), 7 patients had low grade glioma (ganglioglioma =1, brain stem glioma n = 1, astrocytoma II n = 1, pontine glioma, oligodendroglioma n = 2, unspecified n = 1) and one patients has brain metastasis (malignant melanoma). Five patients had been exposed to anti-angiogenetic chemotherapy (Bevacizumab + irinotecan). Median tumor volume was 1.6 ml (range 0-138 ml). Areas with visually increased BV were observed in 15 of 18 scans with metabolically active tumor tissue. Scans with increased BV had significantly larger median FET-vol (4.1 ml vs 0 ml, p < 0.0005) and median Tmax/B (2.5 vs 1.4, p < 0.005) compared to those with without increased BV. Excluding scans without metabolically active tumor tissue, neither FET-vol nor Tmax/B was different. There was a high variability in the regional signals observed using FLAIR, FET PET, BV, and post-contrast T1, and poor spatial congruence between FET and BV. The fraction of scans with and without increased BV was not related to tumor grade or exposure to Bevacizumab. CONCLUSION: In the clinical management of brain tumors a simultaneous and comprehensive evaluation of structure, metabolism and blood volume is feasible in a short single session FET PET/MRI DSC scan yielding complementary high quality information. This modality may provide valuable insight into tumor biology and increase the overall diagnostic quality, decrease clinical decision time, and increase acceptance of PET imaging with patients and treating clinicians in clinical management and in trials.

A low-energy enhancement of the $\ensuremath{\gamma}$-ray strength function in several light and medium-mass nuclei has been observed recently in $^{3}\mathrm{He}$-induced reactions. The effect of this enhancement on $(n,\ensuremath{\gamma}$) cross sections is investigated for stable and unstable neutron-rich Fe, Mo, and Cd isotopes. Our results indicate that the radiative neutron capture cross sections may increase considerably due to the low-energy enhancement when approaching the neutron drip line. This could have non-negligible consequences on r-process nucleosynthesis calculations.

Denne oppgaven tar for seg deler av Zygmunt Baumans tidlige forfatterskap, hovedsakelig i perioden 1966 – 1976. Oppgaven vil vise at man hos Bauman kan finne en interesse for samfunnsvitenskapene og sosiologiens kulturelle betydning, og da spesielt deres betydning for historiske endringsprosesser. Hans utgangspunkt kan skisseres som følger: På linje med all øvrig institusjonalisert intellektuell virksomhet, har vitenskapene om menneske og samfunn alltid visse praktiske konsekvenser. I følge Bauman bidrar de kort sagt til å forme historiske, kulturelle og sosiale betingelser for menneskelige liv. Det er imidlertid ikke gitt en gang for alle hvilke praktiske innvirkninger vitenskapene kan ha, og heller ikke hvilke innvirkninger de bør ha. Foreliggende oppgave belyser hvordan Bauman besvarer slike og lignende spørsmål i hans mest sentrale arbeider fra perioden. Samtidig knytter den Baumans perspektiver opp til andre tenkere og teoretikere, i første rekke av marxistisk orientering.

An isomeric state in {sup 255}Lr with a half-life of t{sub 1/2} = 1.4(1) ms and E{sub x}>720-keV has been observed for the first time using the GABRIELA setup at the focal plane of the VASSILISSA separator. Based on its K-forbiddeness, the configuration of the state is most probably formed by coupling the valence proton to a two quasiparticle neutron excitation. Possible three quasiparticle configurations are discussed.

BACKGROUND: Bevacizumab, a monoclonal antibody targeting vascular endothelial growth factor A (VEGF-A) has shown activity in the treatment of recurrent malignant glioma. Predictive markers and prognostic models are required in order to individualize treatment for grade 3 glioma patients. The primary endpoint of this study was to identify predictive biomarkers associated with response to bevacizumab therapy. The secondary endpoint was to identify prognostic factors associated with progression-free survival (PFS) and overall survival (OS). METHODS: A total of 62 consecutive, recurrent grade 3 glioma patients were administered bevacizumab and irinotecan between December 2005 and November 2014 according to a previously published clinical protocol. A wide range of clinical, histopathological and molecular factors were screened for significant correlation (p < 0.05) with response and survival endpoints using logistic and Cox regression, respectively. Potentially predictive biomarkers were subjected to multivariate analysis. The landmark method was employed for analysis of survival by response. RESULTS: Twenty-two of 57 evaluable patients (38.6 %) demonstrated a response at the time of their best response MRI (RANO criteria). Responders had significantly prolonged OS (p = 0.007) and trended toward longer PFS (p = 0.067) as compared to non-responders (OS: 12.4 vs 4.3 months, PFS: 5.6 vs 3.2 months). A favorable WHO performance status (PS) and absence of necrosis were significantly more common in responders than non-responders. Multivariate analysis also identified a poor PS as the only prognostic factor for PFS, while an unfavorable PS and immunohistochemical p53 accumulation were prognostic of reduced OS. CONCLUSIONS: A poor baseline PS and the presence of necrosis were negatively associated with response to bevacizumab. An unfavorable PS and p53 positivity are prognostic of worse outcome in this patient population.

Excited states in {sup 249}Fm were populated via the {alpha} decay of {sup 253}No and the subsequent decay was observed with the GABRIELA detection system installed at the focal plane of the VASSILISSA recoil separator. The energies, spins, and parities of these states could be established through combined {alpha},{gamma}, and conversion-electron spectroscopy. The first members of the ground-state rotational band were identified. Their excitation energies as well as the observation of a cross-over E2 transition confirm the assignment of 7/2{sup +}624 for the ground state of {sup 249}Fm. Two excited states were also observed and their decay properties suggest that they correspond to the particle excitation 9/2{sup -}734 and hole excitation 5/2{sup +}622. The analysis suggests that the 279-keV transition de-exciting the 9/2{sup -} state has anomalous E1 conversion coefficients.

Level densities for $^{93\ensuremath{-}98}\mathrm{Mo}$ have been extracted using the ($^{3}\mathrm{He}$,$\ensuremath{\alpha}\ensuremath{\gamma}$) and ($^{3}\mathrm{He}$,$^{3}\mathrm{He}$${}^{'}\ensuremath{\gamma}$) reactions. From the level densities thermodynamical quantities such as temperature and heat capacity can be deduced. Data have been analyzed by utilizing both the microcanonical and the canonical ensemble. Structures in the microcanonical temperature are consistent with the breaking of nucleon Cooper pairs. The $\mathsf{S}$ shape of the heat capacity curves found within the canonical ensemble is interpreted as consistent with a pairing phase transition with a critical temperature for the quenching of pairing correlations at ${T}_{c}~0.7\ensuremath{-}1.0$MeV.

The bucket foundation is a new type of foundation, which has been developed over the past 3 years and today it is used for a Vestas V90-3.0 MW offshore wind turbine as a prototype. Ibsen et al.(2003). The bucket foundation is believed to have great potential in the future offshore wind parks as the wind turbines are getting larger and more effective. The behaviour of bucket foundations located in saturated dense sand has been investigated by use of model tests. One of the methods to predict the response of a full size bucket foundation is the Finite Element Method, FEM. This method has been used to back calculate the response of the model tests in the laboratory. It has been shown that a three-dimensional Finite Element model is a useful method to predict the behaviour of bucket foundations for offshore wind turbines installed in saturated sand. The bucket foundation is a new type of foundation, which has been developed over the past 3 years and today it is used for a Vestas V90-3.0 MW offshore wind turbine as a prototype. Ibsen et al.(2003). The bucket foundation is believed to have great potential in the future offshore wind parks as the wind turbines are getting larger and more effective. The behaviour of bucket foundations located in saturated dense sand has been investigated by use of model tests. One of the methods to predict the response of a full size bucket foundation is the Finite Element Method, FEM. This method has been used to back calculate the response of the model tests in the laboratory. It has been shown that a three-dimensional Finite Element model is a useful method to predict the behaviour of bucket foundations for offshore wind turbines installed in saturated sand.

An unexpected enhancement in the γ-strength function for E≤ 3MeV for Ti, Sc, V, Fe, and Mo nuclei close to the valley of stability has been discovered at the Oslo Cyclotron Laboratory. Provided that this enhancement is present also in very neutron-rich nuclei, it could give an increase in the neutron-capture rates up to two orders of magnitude. However, it is still an open question whether this structure persists when approaching the neutron drip line.