Standardiserte konstruksjonselementer av fiberarmert polymer for vegbru : Design og dimensjonering av elementer for standardisering og bruk i vegbruer

Masteroppgave bygg BYG500 - Universitetet i Agder 2017This thesis is addressing the possibility for use of fiber reinforced polymers (FRP) in bridge constructions in Norway. The aim is to design an FRP section that can perform as both structural support and decking on the bridge, in a similar way as often is done with concrete. The advances of using FRP composites is that it is possible to make the bridge sections a lot lighter, and consequently possible to fabricate them in remote locations and transport them to the construction site. This will make the time necessary for construction on site a lot shorter in cases where old bridges need replacement. To make FRP-composite bridges economically feasible it is necessary to make a section that can be reproduced many times over, as much of the cost of a composite section is in the making of formwork. Making a standardized section will hopefully also bring down the time and cost of engineering the bridge. In this thesis, the focus is on a standardized section that can be used on bridges up to 10 meters in span. In Norway, there are 18 199 bridges, and approximately 10 000 of these are under 10 meters, which means that there is a lot to be gained from standardizing with these constraints. In FRP composites, low elasticity modulus (Young’s modulus) [1] gives problems with deflection long before the loads are high enough to give problems with strength. This is opposite of what is the case with materials as concrete and steel were strength of the material often becomes a problem before the maximum deflection. In a stiffness based design of a bridge, the deflection requirement is given by The Norwegian Public Roads Administration (NPRA), who is the governing authority on the construction and building of bridges in Norway. Through their manuals, they give requirements for how a bridge shall behave under different circumstances. The N400 manual[2] is the most specific for bridge construction, and specifies that a bridge should maximum deflect L/350. In the case of a 10-meter bridge that gives a deflection of maximum 28,6 millimeters. Using finite element analysis and application of theory as well as material data from laboratory testing, this thesis will try to fulfill this requirement. The conclusion of this thesis is that it is possible to produce a standardized composite element consisting of several identical items glued together for use as bridge decking together with edge beams. This bridge construction is very light weight, in fact so light that adding asphalt will triple its weight. It is a wish from the NPRA to make standardized alternatives in different materials to see which is the most efficient in terms of execution time and price. FRP composites is a lighter alternative so that transport from fabrication and storage, out to the mounting site is a lot easier to execute than for heavier material as concrete and steel. It is also easier to maintain, as there is no steel beams, reinforcing steel or steel bearings in the bridge that can corrode

Tickborne Encephalitis Virus, Norway and Denmark

Serum from 2 Norwegians with tickborne encephalitis (TBE) (1 of whom was infected in Denmark) and 810 Norwegian ticks were tested for TBE virus (TBEV) RNA by reverse transcription–polymerase chain reaction. Sequencing and phylogenetic analysis were performed. This is the first genome detection of TBEV in serum from Norwegian patients

Enhancement of cranial nerves in Lyme neuroborreliosis: incidence and correlation with clinical symptoms and prognosis

Purpose Symptoms of cranial neuritis are a common presentation of Lyme neuroborreliosis (LNB). Imaging studies are scarce and report contradictory low prevalence of enhancement compared to clinical studies of cranial neuropathy. We hypothesized that MRI enhancement of cranial nerves in LNB is underreported, and aimed to assess the prevalence and clinical impact of cranial nerve enhancement in early LNB. Methods In this prospective, longitudinal cohort study, 69 patients with acute LNB were examined with MRI of the brain. Enhancement of cranial nerves III–XII was rated. MRI enhancement was correlated to clinical fndings of neuropathy in the acute phase and after 6 months. Results Thirty-nine of 69 patients (57%) had pathological cranial nerve enhancement. Facial and oculomotor nerves were most frequently afected. There was a strong correlation between enhancement in the distal internal auditory canal and parotid segments of the facial nerve and degree of facial palsy (gamma=0.95, p<.01, and gamma=0.93, p<.01), despite that 19/37 nerves with mild-moderate enhancement in the distal internal auditory canal segment showed no clinically evident palsy. Oculomotor and abducens nerve enhancement did not correlate with eye movement palsy (gamma=1.00 and 0.97, p=.31 for both). Sixteen of 17 patients with oculomotor and/or abducens nerve enhancement had no evident eye movement palsy. Conclusions MRI cranial nerve enhancement is common in LNB patients, but it can be clinically occult. Facial and oculomotor nerves are most often afected. Enhancement of the facial nerve distal internal auditory canal and parotid segments correlate with degree of facial palsy.publishedVersio

Enhancement of cranial nerves in Lyme neuroborreliosis: incidence and correlation with clinical symptoms and prognosis

Purpose Symptoms of cranial neuritis are a common presentation of Lyme neuroborreliosis (LNB). Imaging studies are scarce and report contradictory low prevalence of enhancement compared to clinical studies of cranial neuropathy. We hypothesized that MRI enhancement of cranial nerves in LNB is underreported, and aimed to assess the prevalence and clinical impact of cranial nerve enhancement in early LNB. Methods In this prospective, longitudinal cohort study, 69 patients with acute LNB were examined with MRI of the brain. Enhancement of cranial nerves III–XII was rated. MRI enhancement was correlated to clinical findings of neuropathy in the acute phase and after 6 months. Results Thirty-nine of 69 patients (57%) had pathological cranial nerve enhancement. Facial and oculomotor nerves were most frequently affected. There was a strong correlation between enhancement in the distal internal auditory canal and parotid segments of the facial nerve and degree of facial palsy (gamma = 0.95, p < .01, and gamma = 0.93, p < .01), despite that 19/37 nerves with mild-moderate enhancement in the distal internal auditory canal segment showed no clinically evident palsy. Oculomotor and abducens nerve enhancement did not correlate with eye movement palsy (gamma = 1.00 and 0.97, p = .31 for both). Sixteen of 17 patients with oculomotor and/or abducens nerve enhancement had no evident eye movement palsy. Conclusions MRI cranial nerve enhancement is common in LNB patients, but it can be clinically occult. Facial and oculomotor nerves are most often affected. Enhancement of the facial nerve distal internal auditory canal and parotid segments correlate with degree of facial palsy.publishedVersio

Six versus 2 weeks treatment with doxycycline in European Lyme neuroborreliosis: a multicentre, noninferiority, double-blinded, randomised and placebocontrolled trial

Background There is limited evidence regarding optimal duration of antibiotic treatment in neuroborreliosis. We aimed to compare efficacy and safety of oral doxycycline for 2 and 6 weeks in European Lyme neuroborreliosis (LNB). Methods The trial had a randomised, double-blinded, placebo-controlled, non-inferiority design. Patients with LNB were recruited from eight Norwegian hospitals and randomised to doxycycline 200 mg once daily for 2 weeks, followed by 4 weeks of placebo, or doxycycline 200 mg once daily for 6 weeks. The primary endpoint was clinical improvement as measured by difference in a Composite Clinical Score (0–64 points) from baseline to 6 months. The non-inferiority margin was predetermined to 0.5 points. Results One hundred and twenty-one patients were included. Fifty-two treated for 2 weeks and 53 for 6 weeks were included in the intention-to-treat analyses, and 52 and 51 in per-protocol analysis. Mean difference in clinical improvement between the groups was 0.06, 95% CI −1.2 to 1.2, p=0.99 in the intention-to-treat population, and −0.4, 95% CI −1.4 to 0.7, p=0.51 in the per-protocol population and non-inferiority could not be established. There were no treatment failures and no serious adverse events. The groups did not differ in secondary outcomes including clinical scores at 10 weeks and 12 months, cerebrospinal fluid data and patient-reported outcome measures. Patients receiving 6 weeks doxycycline reported slightly more side effects in week 5. Conclusion Our results strongly indicate that there are no benefits of doxycycline treatment beyond 2 weeks in European LNB.publishedVersio

Assessment of cognitive function, structural brain changes and fatigue 6 months after treatment of neuroborreliosis

publishedVersionPaid Open Acces

Genetic epidemiology of amyotrophic lateral sclerosis in Norway - a 2-year population based study

Background: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that affects motor neurons. In Europe, disease-causing genetic variants have been identified in 40-70% of familial ALS patients and approximately in 5% of sporadic ALS patients. In Norway, the contribution of genetic variants to ALS has not yet been studied. In light of the potential development of personalized medicine, knowledge of genetic causes of ALS in a population is becoming increasingly important. The present study provides clinical and genetic data on familial and sporadic ALS patients in a Norwegian population-based cohort. Methods: Blood samples and clinical information from ALS patients were obtained at all 17 neurological departments throughout Norway during a 2-year period. Genetic analysis of the samples involved expansion analysis of C9orf72 and exome sequencing targeting 30 known ALS-linked genes. The variants were classified using genotype-phenotype correlations and bioinformatics tools. Results: A total of 279 ALS patients were included in the study. Of these, 11.5% had one or several family members affected with ALS, whereas 88.5% had no known family history of ALS. A genetic cause of ALS was identified in 31 individuals (11.1%), among which 18 (58.1%) were familial and 13 (41.9%) were sporadic. The most common genetic cause was the C9orf72 expansion (6.8%), which was identified in 8 familial and 11 sporadic ALS patients. Pathogenic or likely pathogenic variants of SOD1 and TBK1 were identified in 10 familial and 2 sporadic cases. C9orf72 expansions dominated in patients from the Northern and Central regions, whereas SOD1 variants dominated in patients from the South-Eastern region. Conclusion: In the present study, we identified several pathogenic gene variants in both familial and sporadic ALS patients. Restricting genetic analysis to only familial cases would miss more than 40 percent of those with a disease-causing genetic variant, indicating the need for genetic analysis in sporadic cases as well.publishedVersio

The movement of five wrasse species (Labridae) on the Norwegian west coast.

During the 1980`s it was discovered that fishes from the wrasse family (Labridae) along the Norwegian coast could be utilized as cleaner fish for controlling sea-lice infestations in commercial fish farming. Since this discovery, the demand for wild-caught wrasse has generated a large and profitable fishery. And subsequently, knowledge regarding the biology and ecology of temperate wrasses is needed to manage a sustainable fishery. In this thesis, I analyzed movements of the five wrasse species using mark-recapture data collected over five periods in 2017 and 2018 on three islands outside Huftarøy in Austevoll municipality in western Norway. A total of 8454 wrasses were tagged, and 839 were recaptured. The five species of wrasse found at the study location; Corkwing (Crenilabrus melops), goldsinny (Ctenolabrus rupestris), ballan wrasse (Labrus bergylta), rock cook (Centrolabrus exoletus) and cuckoo wrasse (Labrus mixtus). Horizontal movement made by individuals from these species was obtained by calculating the distance between observations. Life-history traits and environmental factors were then used in order to explain movement patterns. In this thesis, I found that the five species of wrasse moved locally with little horizontal movement. This was reinforced by the lack of observations of movement between the three islands. Corkwing wrasse was found to have moved longer distances with larger body size, and the island and habitat where captured had an effect on the distance traveled. Goldsinny wrasse was found to move shorter distances than corkwing, and the island where captured influenced horizontal movement. Factors influencing the recapture probability was found to mirror factors influencing movement, and the time of year influenced the probability of being recaptured. Local island populations of territorial fishes such as the wrasses in this study are particularly vulnerable to overexploitation and would likely struggle to recover. The movement patterns observed for corkwing make this species especially susceptible to sex-selective harvesting, which can have a negative impact on population productivity. The way fishes move is directly linked with the probability of being harvested. In order to protect small local populations of temperate wrasses, further research on wrasse movement should be carried out with different techniques such as acoustic or radio telemetry in order to get a more detailed understanding of the movement patterns of the five species of wrasse found along the Norwegian coast

Risk factors for a non-favourable outcome after treated European Neuroborreliosis

Aim: To identify risk factors for a non-favourable long term outcome with respect to Health Related Quality of Life (HRQoL) and fatigue after treated Lyme Neuroborreliosis (LNB). Methods: We followed 50 LNB patients, and assessed outcome by the self-report questionnaires Short Form-36 (SF-36) and Fatigue Severity Scale (FSS) 30 months after treatment. We analyzed associations between these outcomes and demographical, clinical and laboratory data by univariate analyses and linear regression. Clinical status was assessed by a composite score based on subjective complaints and objective findings. Results: Pre-treatment symptom duration > 6 weeks (B=-10.2, P=0.002) and non-complete recovery at 12 months (B=-5.6, P=0.033) were associated with lower scores in the SF-36 domain Physical Component Summary (R2=0.59). Non-complete recovery at 4 months was associated with lower scores in the SF-36 domain Mental Component Summary (B=-8.9, P=0.01 (R2= 0.37)). Pre-treatment symptom duration > 6 weeks (B=1.3, P= 0.028), high scores on the composite clinical score pre-treatment (B=0.1, P=0.019) and non-complete recovery at 12 months (B=1.7, P=0.001) were associated with higher FSS scores (R2=0.70). No laboratory test results were associated with these outcomes. Conclusions: Delayed treatment start, more symptoms and findings before and non-complete recovery at 4 and 12 months after treatment seem to predict a non-favourable outcome regarding HRQoL and fatigue 30 months after treated LNB. Age, gender, educational level involvement of the central nervous system pre-treatment, coexisting diseases and cerebrospinal fluid findings before treatment and during follow-up, were not long term HRQoL and fatigue