NORA - Norwegian Open Research Archives
Not a member yet
344281 research outputs found
Sort by
IgG protection status for humoral immune response to MMR vaccine among the Norwegian population of children and method assessment of MMR-Multi-Plex Immunoassay
No full textBackground and aim: In order to prevent sudden outbreaks of serious disease, immune response to vaccines should be monitored to investigate the overall status of protection in a given population as well as identifying susceptible groups or individuals with a reduced or a negative response. The measles -mumps -rubella (MMR) vaccine is a live-attenuated combined vaccine used for the prevention of measles, mumps, and rubella. The main purpose of this study was to investigate the status of protection against measles, mumps, and rubella among the Norwegian population of children using IgG antibody concentrations as an indicator for humoral immune response to the MMR vaccine. An additional goal was to perform method assessment of MMR Multi-Plex Immunoassay by investigating intra-assay precision and interoperator reproducibility of IgG measurements.
The study population and method: The study population were a part of The Norwegian Mother, Father and Child Cohort study (MoBa) including 306 children between the ages of 7 and 14. The collection of experimental material was performed by the Norwegian Environmental Biobank (NEB) during 2016-2017. The plasma IgG against measles, mumps, and rubella pathogen antigens were analysed using MMR Multi-Plex Immunoassay. Following IgG “protective levels” were set for each antigen: measles; >200 mIU/ml, mumps; >500 AU/ml, and rubella; >10 IU/ml, where concentrations below these thresholds were considered as “unprotected”. The intra-assay precision assessment was performed by the investigation of CV% values, and inter-operator reproducibility assessment was accomplished with the help of scatter plots, Lin’s Concordance Correlation Coefficient analysis, Bland-Altman plots, and reanalysis of plasma samples.
Results: The majority of IgG antibody concentrations were above ‘protective level’ for all three antigens (measles: 97.1%, mumps: 63.1%, rubella: 89.2%). Overall, 2.3% of the children had IgG antibody concentrations below ‘protective level’ for all the three antigens. Notably, the proportion of ‘unprotected’ children varied for the three pathogens with lowest protection rates for mumps (36.9% below protection limit) while only 2.9% and 10.8% were ‘unprotected’ for measles and rubella respectively. The intra-assay precision results showed high precision with low mean CV% values of duplicates for all the three antigens (measles: 3.9%, mumps: 3.0% and rubella: 3.5%). The assessment of inter-operator reproducibility showed an overall high agreement between operators for IgG levels measured against all three pathogens.
Conclusion: According to obtained results, the MMR Multi-Plex Immunoassay revealed a good intra-assay precision for the measurement of IgG levels against measles, mumps, and rubella. The results indicate an overall high degree of IgG antibody protection against measles, mumps, and rubella within the study population, which further indicates a substantial MMR vaccine effectiveness and heard immunity. However, a larger proportion of children were unprotected against mumps in comparison to measles and rubella indicating a possible need for booster vaccines or advances in vaccine technology against mumps
Urban agriculture for food secure cities? : the case of Cuba
No full textDuring the last decades, urban and peri-urban agriculture initiatives have emerged in cities across the world as a response to increased urbanization, climate change, and food insecurity. In the case of Cuba, the rise of urban agriculture started as a response to the crisis that occurred after the fall of the Soviet Union. Due to food shortage and a failing agricultural sector the Cuban people, a population consisting of mostly urban settlers, implemented an urban food production system. This case is often represented as a success story in which urban agriculture saved Cuba in a time of crisis. Therefore, the objective of this thesis is to assess how urban agriculture has contributed to food security in Cuba. To do this, I will analyze food security outcomes using a six-dimensional framework (availability, access, utilization, stability, agency, and sustainability). The findings are based on a desk study of secondary sources. The paper concludes that although urban agriculture is an important element of the Cuban agricultural sector and certainly contributed to the increase in food security Cuba has experienced since the 1990s, the contribution should not be overestimated. Urban agriculture has diversified production in the agricultural sector through increased production of fruits and vegetables, but challenges related to poor soil quality, access to land, instability, and the organization within the sector continue to create obstacles for urban farmers. Urban agriculture is not the only reason Cuba has experienced improved food security but acts as an important supplement to food imports and rural agriculture
Better coding for learning speech representations
No full textI denne oppgaven er muligheten for å bruke Non-autoregressive Predictive Coding (NPC) til å lære talerepresentasjoner undersøkt. NPC er en selv-overvåket dyp-læringsmetode som, i motsetning til andre vanlige selv-overvåkede metoder, ikke er autoregressiv og kan derfor bli trent raskere. Tre ulike NPC-modeller er trent. En engelsk, en norsk og en adapsjonsmodell trent til norsk med den engelske modellen som en basis.
Undersøkelser av de lerte representasjonene viser at de er på et subfonemisk nivå og mange ulike vektorer brukes for å representere ulike stadier av et fonem. Ulike talere har noe overlapp i bruke represenasjoner for de samme fonemer, men de er ikke helt ulike.
Testing av de lærte representasjonene med en fonemgjenkjenner viser at, i disse eksperimentene, NPC karakteristikkene ikke var i stand til å prestere bedre enn Mel Frequency Cepstral Coefficients (MFCC), hverken den engelske-, den norske- eller adapsjonsmodellen. Adapsjosmodellen klarte å prestere bedre enn den norske modellen og det kan bety at adapsjonstrening kan vere et nyttig hjelpemiddel for talerepresentasjoner i språk med små taledatabaser
Porteføljeforvaltning med forsterkningslæring
No full textOppgaven tar for seg porteføljeforvaltning gjennom anvendelsen av forsterkningslæring. Denne maskinlæringsprosessen skal løse problemstillinger tilknyttet porteføljeforvaltning ved å benytte en handelsagent som lærer gjennom sekvensielle beslutningsprosesser. Agenten skal lære i et fremstilt miljø som representer finansmarkedet. Det benyttes en modellfri forsterkningslæring som tillater agenten å gjennomføre beslutninger fordelt i tidstrinn og samtidig lære optimal handlingsstrategi. Handelssystemet fremstilles gjennom kombinasjonen av finansielle matematiske formuleringer og forsterkningslæringsalgoritmer. Oppgaven anvender forsterkningslæringsalgoritmen Deep Deterministic Policy Gradient som en del av systemet. Tilnærmingen til læringsprosessen er at agenten skal "prøve og feile" for å skape problemløsning. For at dette skal være mulig er det etablert et minne i systemet. På denne måten kan agenten huske hvilke beslutninger som er gjennomført og lære av disse ved neste situasjon. For å undersøke effektene av algoritmen kontrolleres resultater gjennom back-testing på historisk data. Resultatene blir sammenlignet med markedsindeksen Dow Jones, tilhørende børsnoterte fond (DIA) og en mean-variance porteføljestrategi for å undersøke ytelsen av forsterkningslæringsagenten. Denne simuleringen av handel sjekker porteføljens robusthet, lønnsomhet og risikosensitivitet. Undersøkelsene viser lovende resultater som tyder på at forsterkningslæring har egenskapene til å skape vellykkede handelsstrategier
Hvem er rektor? En kvalitativ studie av rektor sin livshistorie i lys av Bourdieu
No full textSkolen er som et av samfunnets viktigste institusjoner under et konstant krysspress når det gjelder ivaretagelse av elevers læringsutbytte, sosial trivsel og mestring, og ikke minst resultat – og økonomistyring. Samtidig er det en forventning av at disse praksiser ikke konkurrerer, men heller forutsetter og utfyller hverandre. Skolens organisasjon og ledelse opplever jevnlig store endringsperioder og iverksettelse av nye reformer. I takt med dette, rettes det en økende forventning til skoleleders kunnskap og kompetanse både på forvaltningsnivå, innen pedagogiskledelse og menneskefag. Organisering og ledelse i utdanningsinstitusjoner krever godt samspill og gode sjonglører. Hvem er det som mestrer og håndterer en såpass krevende lederrolle og funksjon over tid?
Denne masteroppgaven i erfaringsbasert spesialpedagogikk, handler om livshistoriene til tre rektorer, deres erindringer og beretninger fra sine liv, fra den spede begynnelse i barndom og oppvekst, ungdomstid og utdanningsbane, hendelser og opplevelser som i ulike former har ført frem til å bli skoleleder. Gjennom deres livshistorier har formålet vært å bli bedre kjent med mennesket bak funksjonen Rektor. Jeg har sett på objektive livsvilkår og miljøstrukturer, som kan ha ligget til grunn for utvikling av lederidentitet. Med dette som utgangspunkt er overordnet problemstilling «Hvem er rektor? En kvalitativ studie av rektor sin livshistorie i lys av Bourdieu.
Deres fortellinger er analysert og fortolket i lys av Bourdieu sine begreper om habitus, kapital og felt, som sammenholdes med teori innen livshistorieforskning og skoleledelse. For å få satt fortellingene inn i en større samfunnsvitenskapelig forståelse, er funn studert i lys av de historiske, sosiale og kulturelle kontekster som livshistoriene står seg sammen med.
Gjennom forskningen mener jeg å ha funnet sterke indikasjoner på arvet og akkumulert kulturell og sosial kapital.
Nøkkelord: livshistorieforskning, rektor, Bourdieu, habitus, kapital og fel
A New Correlation Coefficient for T-Spherical Fuzzy Sets and Its Application in Multicriteria Decision-Making and Pattern Recognition
No full textThe goal of this paper is to design a new correlation coefficient for -spherical fuzzy sets (TSFSs), which can accurately measure the nature of correlation (i.e., positive and negative) as well as the degree of relationship between TSFS. In order to formulate our proposed idea, we had taken inspiration from the statistical concept of the correlation coefficient. While doing so, we firstly introduce the variance and covariance of two TSFS and then constructed our scheme using these two newly defined notions. The numerical value of our proposed correlation coefficient lies within the interval , as it should be from a statistical point of view, whereas the existing methods cannot measure the negative correlation between TSFS, as their numerical value falls within the interval , which is not reasonable both statistically and intuitively. This aspect has also been thoroughly demonstrated using some numerical examples. The comparison results witnessed the dominance and upper hand of our proposed method over the existing definitions, with reliable and better results. In order to demonstrate the feasibility, usefulness, and practical application, we applied our proposed scheme to solve technical and scientific problems of multicriteria decision-making and pattern recognition. The numerical results show that our proposed scheme is practically suitable, technically applicable, and intuitively reasonable
Design and Implementation of Mechatronics Home Lab for Undergraduate Mechatronics Teaching
No full textThe field of mechatronics is a multidisciplinary field of engineering, where the combination of physical components and theory from several engineering fields is applied to build complex machines. Mechatronics education is an active learning process through practical laboratory exercises and problem-based learning. This paper presents the design and implementation of a mechatronics home lab to support undergraduate mechatronics teaching. The purpose is to support theoretical teaching in mechatronics with a low-cost, 3D-printable platform where the students can experiment and practice instrumentation and control theory with a practical problem-based approach. Five projects were introduced for experiment implementation of the developed home lab. Throughout these experiments, it is intended to facilitate the understanding of theories and concepts in mechatronics, and enhance the ability to design and implementation of experiments, the collection and analysis of data, and the conducting of simulation in MATLAB
Randomized controlled light intervention in an occupational setting and the effects on stress and work performance
No full textBackground: Coping with stress is crucial for the individual to retain a healthy work-life balance, work satisfaction and work performance. Light has powerful effects on mood, sleep, and the circadian biorhythms, and disruption of circadian biorhythms is associated with several diseases. Here we examine the relationship between positive stress and work performance, and if outdoor light exposure positively affects both stress and work performance.
Methods: We performed randomized controlled trial with light intervention with 18 subjects in a call center, and we assessed various parameters of work performance and stress.
Results: We identified positive correlation between some of the stress parameters and work performance parameters, including a positive correlation between work performance parameters and the affect part of the stress experience. We did not find such correlation with the perceived stress part or the circadian vulnerability part of the stress experience, nor with the stress arousal response. The light intervention did not positively affect the different stress parameters or work performance parameters.
Conclusions: Our studies constitute an important first pilot with regards to finding relationships between occupational stress and employee-level performance. We tested an intervention with outdoor lunchtime light exposure as a simple measure that can be easily adapted in work environments if supported by data. Hence, although our light intervention data did not confirm the partially beneficial effects of light exposure from our initial exploratory studies (Hypothesis #1), further studies of this exiting relationship is warranted, building on the suggested framework. A bigger size of the study population and a longer duration of the studies would be recommended for future studies
Do health professionals’ attitudes towards alcohol use matter for alcohol prevention efforts? Results from the WIRUS-OHS study
No full textBACKGROUND: Use of alcohol is a major public health issue, representing the 7th largest burden of disease in the world. Workplaces offer a unique arena for health initiatives addressing alcohol use, where occupational health services (OHS) personnel play an important role. However, we do not know if the extent of such initiatives may be influenced by personal drinking attitudes among OHS personnel. Thus, the aim of the study was to explore how drinking attitudes among OHS personnel were associated wit their frequency of working with alcohol-related cases and with their views on alcohol prevention activities in the OHS. METHODS: The WIRUS project included a cross-sectional survey of attitudes and practices among OHS personnel (n=325) employed by Norwegian OHS services (n=69), who informed about sociodemographics and professional characteristics, drinking attitudes, frequency of cases with alcohol-related issues, and perceptions toward the role of the OHS in primary, secondary, and tertiary prevention activities. Measures of associations were examined with linear and logistic regression models. RESULTS: Drinking attitudes were unrelated to the frequency of working with alcohol-related cases. Physicians, psychologists, and nurses had higher frequency of working with alcohol-related cases, compared to those with other professional backgrounds (β=0.46, p=0.01). Drinking attitudes were also unrelated to attitudes towards primary/secondary/tertiary prevention activities in OHS, while female OHS personnel were more positive towards increased primary alcohol prevention in the OHS (OR:1.82, p<0.05). Only marginal portions (1%-3%) of the variance in attitudes towards alcohol prevention activities in the OHS were accounted for by the models. CONCLUSION: This study did not find evidence of associations between OHS personnel's drinking attitudes and their practices towards alcohol prevention activities. The lack of association between OHS personnel's attitudes towards alcohol use and their attitudes and practices relating to alcohol prevention in the workplace might point towards professionalism, as personal attitudes appear not to interfere with their priorities and professional mission. Given the small amount of outcome variance explained by the tested models, other variables should be used in future studies
