374 research outputs found
Age, modifiable risk factors, and mortality. : A 42 years prospective follow-up study in a general population.
No full textRisikoforebygging er en viktig del av alt helsearbeid, men det meste av evidens med hensyn på forebyggende helsearbeid er fremkommet ved studier utført på middelaldrende befolkningsgrupper med ulik ekstern validitet, med variabel oppfølgingstid, og med overvekt av menn. Modifiserbare risikofaktorer har potensielt ulik innvirkning i ulike aldersgrupper, i ulike faser av en lengre oppfølgingstid og med hensyn på forskjellige endepunkter (dødelighet: total og årsaksspesifikk).
Målsetning: å studere forskjeller og likheter i effekten av livsstilsrelaterte risikofaktorer (særlig kroppsmasseindeks, fysisk aktivitet og lungefunksjon) på total dødelighet og årsaksspesifikk dødelighet som følge av hjerneslag og koronar hjertesykdom i ulike aldersgrupper av menn og kvinner i en generell norsk befolkning med 42 års oppfølgingstid. Materiale og metode: 6811 tilfeldig utvalgte menn og kvinner i alderen 20-79 og bosatt i Bergen i 1964 ble invitert til en utvidet helseundersøkelse etter Blodtrykksundersøkelsene. 5653 personer møtte frem til undersøkelsen der 208 kliniske og selvrapporterte variabler ble registrert. Datamaterialet ble koblet mot Levekårsundersøkelsene i 1970-80-90 og 2000, Dødsårsaksregisteret (2005) og Folkeregisteret (2007). Cox-regresjon ble brukt for å studere sammenhengen mellom utvalgte variabler og dødelighet.
Resultater: Kroppsmasseindeks er assosiert til overdødelighet i yngre aldersgrupper, men er tilsynelatende inverst assosiert til dødelighet i eldre aldersgrupper, selv etter justering for multiple variabler og i subgruppeanalyser av de friskeste i utvalget. Fysisk aktivitet er minst like sterkt assosiert til overlevelse blant de eldre som i de yngre aldersgruppene, i motsetning til de fleste andre kjente risikofaktorer som har avtakende styrke i sin assosiasjon til død med økende alder. Lungefunksjon er inverst assosiert til risiko for dødelig hjerneslag. Validiteten av hjerneslag og koronar hjertesykdom registret som tilgrunnliggende dødsårsak i Dødsårsaksregisteret i perioden 1965-2005 er tilfredsstillende for bruk i epidemiologisk forskningsarbeid.
Konklusjon: Livsstil har implikasjoner for overlevelse i alle aldersgrupper. Fysisk aktivitet, kroppsmasseindeks og lungefunksjon er viktige livsstilsrelaterte prediktorer for god helse og økt overlevelse også blant gamle
Migration of 137 CS from air to soil and plants in the Gulsvik area, Norway after the Chernobyl reactor accident.
No full textA migration of 137 Cs from air to soil and vegetation after the Chernobyl accident is studied using the concentrations measured in the Gulsvik area in Norway. The major part of the 137 Cs from soil to plants through their root system is not a rapid process. Only a few per cent of the deposition can be traced in plants. This seems to suggest that as far as 137 Cs is concerned, an effect of the Chernobyl releases is not an acute but a long-term phenomenon. The 137 Cs accumulation in soils is rather high but does not result in 137 Cs levels in plants and diet higher than acceptable in Norway
Spirometry reference equations for central European populations from school age to old age.
No full textSpirometry reference values are important for the interpretation of spirometry results. Reference values should be updated regularly, derived from a population as similar to the population for which they are to be used and span across all ages. Such spirometry reference equations are currently lacking for central European populations. To develop spirometry reference equations for central European populations between 8 and 90 years of age. We used data collected between January 1993 and December 2010 from a central European population. The data was modelled using "Generalized Additive Models for Location, Scale and Shape" (GAMLSS). The spirometry reference equations were derived from 118'891 individuals consisting of 60'624 (51%) females and 58'267 (49%) males. Altogether, there were 18'211 (15.3%) children under the age of 18 years. We developed spirometry reference equations for a central European population between 8 and 90 years of age that can be implemented in a wide range of clinical settings
Prognostic factors of asthma severity: a 9-year international prospective cohort study
No full textTo access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldBACKGROUND: The natural history of asthma severity is poorly known. OBJECTIVE: To investigate prognostic factors of asthma severity. METHODS: All current patients with asthma identified in 1991 to 1993 in the European Community Respiratory Health Survey were followed up, and their severity was assessed in 2002 by using the Global Initiative for Asthma categorization (n = 856). Asthma severity (remittent, intermittent, mild, moderate, severe) was related to potential determinants evaluated at baseline and during the follow-up by a multinomial logistic model, using the intermittent group as the reference category for relative risk ratios (RRRs). RESULTS: Asthma severity measured at baseline was a determinant of a patient's severity at the end of the follow-up. At baseline, severe persistent had a poorer FEV1% predicted, a poorer symptom control, higher IgE levels (RRR, 2.06; 95% CI, 1.38-3.06), and a higher prevalence of chronic cough/mucus hypersecretion (RRR, 4.90; 95% CI, 2.18-11.02) than patients with intermittent asthma. Moderate persistent showed the same prognostic factors as severe persistent, even if the associations were weaker. Mild persistent had a distribution of prognostic factors that was similar to patients with intermittent asthma, although the former showed a poorer symptom control than the latter. Remission mainly occurred in patients with less severe asthma and was negatively associated with a change in body mass index (RRR, 0.86; 95% CI, 0.75-0.97). Allergic rhinitis, smoking, and respiratory infections in childhood were not associated with asthma severity. CONCLUSION: Patients with moderate and severe persistent asthma are characterized by early deterioration of lung function. High IgE levels and persistent cough/mucus hypersecretion are strong markers of moderate/severe asthma, which seems to be a different phenotype from mild persistent or intermittent asthma. CLINICAL IMPLICATIONS: Our results suggest that the evolution of asthma severity is to a large extent predictable
Bronchitic symptoms and their relation to FEV1 in Italy, Sweden and Norway
No full textWithin the EU BioMed 1 concerted action on the epidemiology of chronic obstructive pulmonary disease (COPD), a comparison was made in a pooled database from Italy, Sweden and Norway, of smoking habits, symptoms common in COPD, their relation to forced expiratory volume in one second (FEV1), and risk factors for COPD. COPD in these analyses has been defined following the British Thoracic Society's guidelines (i.e. FEV1/vital capacity (VC) <70% and FEV1 <80% of predicted values (% pred)), and by using a more severe disease criterion defined as FEV1/VC <60%, and FEV1 <60% pred. The pooled data were from the Italian Po River Delta Study II performed in 1988-1991, the Obstructive Lung Disease in Northern Sweden Study I (1985-1987), and the study performed in the city of Bergen and its surroundings in Hordaland, Western Norway in 1985-1986. The proportion of male smokers was 42% in the Italian, 34% in the Swedish, and 33% in the Norwegian samples. The corresponding figures for females were 30% in Sweden, 25% in Italy, and 23% in Norway. The prevalence of any wheeze was 28% in the Norwegian versus 21% in both the Italian and the Swedish samples. The prevalence of sputum production was 20% both in Norway and Sweden, while it was 16% in Italy. All symptoms were strongly smoking dependent. The relation between lung function impairment and respiratory symptoms was also strongly dependent on age. Among young symptomatic subjects, the lung function was only slightly affected. In symptomatic subjects >60 yrs, the mean FEV1 was 76-81% pred among Norwegian males. The corresponding values were 83-84% in Sweden, and 79-88% in Italy. Among females, a similar lung function impairment was found, but the variation of the mean FEV1 values was large. Risk factors for chronic obstructive pulmonary disease were calculated by multiple logistic regression analysis. The dominating risk factor was age followed by smoking. Smoking yielded an odds ratio of 3.6 for chronic obstructive pulmonary disease, defined according to the British Thoracic Society's guidelines, while the odds ratio for smoking as a risk for the more severe chronic obstructive pulmonary disease was 5.3. Country and sex had no significant influence. However, for the more severe chronic obstructive pulmonary disease, living in Norway was associated with an odds ratio of 1.8, and living in Sweden with an odds ratio of 1.5 compared with living in Italy
Quality-of-life and asthma-severity in general population asthmatics: results of the ECRHS II study
No full textBACKGROUND: Health-related quality-of-life (HRQL) has been poorly studied in large samples of asthmatics from the general population. HRQL and its relationship to asthma-severity were assessed among 900 asthmatics enrolled in the European Community Respiratory Health Survey. METHODS: Among asthmatics, 864 completed the short form-36 (SF-36) questionnaire and 477 also completed the Asthma Quality-of-life Questionnaire (AQLQ). A 4-class asthma-severity scale, combining clinical items, forced expiratory volume in 1 s and the level of treatment and the different asthma-severity components (each of the clinical items and hospitalization) were studied in relation to HRQL. RESULTS: Mean SF-36 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores (45.5 and 48.8 respectively) were lower than expected in a general population. The mean total AQLQ score was 5.8. The AQLQ score and to a lesser extent the PCS score were significantly related to the 4-class asthma-severity scale, although the risk of having a lower HRQL score did not vary proportionally across the levels of severity. Asthma-severity had no impact on the MCS score. Asthma attack frequency and hospitalization were associated with both total AQLQ and PCS scores, whereas nocturnal symptoms and lung function were more strongly related to the AQLQ and PCS score respectively. CONCLUSION: In population-based asthmatics, the specific AQLQ questionnaire, and also to a lesser extent the generic SF-36 questionnaire, were sensitive to asthma-severity. Frequencies of asthma attacks, of nocturnal symptoms and hospitalization for asthma have independent impact on HRQL
KNOWLEDGE REGARDING MOTHER-TO-CHILD-TRANSMISSION OF HIV AND BREASTFEEDING PRACTISES IN A POPULATION OF WOMEN WITH A KNOWN HIV-STATUS
No full textThe aim of this study was to assess the knowledge on mother-to-child-transmission (MTCT) of HIV, describe what advice pregnant women receive concerning these issues and investigate breastfeeding practises and infant feeding patterns in general. During six weeks in 2004, a structured interview was carried out among 41 women in Moshi, Tanzania. 11 women were HIV-infected.
90% of the women were aware of MTCT, and 80% knew of the role breastfeeding has in vertical transmission. There was a strong correlation between a higher level of knowledge and increasing age and marital status. When it comes to advice on infant feeding, 100% of the HIV-positive and about half of the non-infected women had received guidance on the topic. The vast majority of women who had been informed on infant feeding, were encouraged to breastfeed exclusively, regardless of their HIV-status.
While 92,7% of the women did breastfeed, only 22% performed exclusive breastfeeding. HIV-positive mothers and mothers of young babies were more likely to breastfeed exclusively. The HIV-infected women stated that fear of revealing their HIV-status was a main reason to why they continued to breastfeed. This is also an important explanation to why exclusive breastfeeding is considered more acceptable and feasible than replacement feeding.
75% of the HIV-positive women did partly succeed in following the recommendations set by WHO concerning infant feeding. This means that they either breastfed exclusively for the first few months or that they abstained from breastfeeding and provided milk substitutes and weaning food for their children in stead
Asthma Among Young Adults in a General Population. Occupational Hazards, Indoor Environment and Diet, 1993
No full textThe aim of the project was to map out the occurrence of asthma in a general population of young adults in Bergen and its relation to vocational position, indoor climate and diet. The project also included a study where one compared the occurrence and variation of asthma prevalence among young people in Hordaland with the results in 15 other European countries. The hypothesis for the project was that vocational position, indoor climate and diets are in causal connection with variable air current obstruction in Norway. One has therefore aimed at registering such effect variables as air way symptoms, lung infection and usage of medication, as well as registering expositional variables such as smoking habits, vocational exposition, diets, house, indoor climate and allergies. It was a cross sectional study where the effect of expositional levels was followed up in longitudinal studies. Phase one consisted of a questionnaire among 4300 persons, in the second phase 1200 persons were called inn for clinical observations and face-to-face interviewing. The sample consists of a random sample of men and women in the age 20-44 years who are living in Bergen pr. 1. October 1991. The sample was drawn by Sentralkontoret for folkeregistrering. Phase one: gross sample 4300, net sample 3450. Phase two: gross sample 1200, net sample 903
Genetics of chronic obstructive pulmonary disease: a case–control study in Bergen, Norway
No full textBattery Management System for a low-cost ROV
No full textA combination of advanced State-of-charge (SoC), State-of-Health (SoH) and State-of-Power (SoP) estimation techniques have been combined into a novel scheme to ensure safe and efficient operation of a battery pack.
A battery model was chosen based on literature review and identified requirements for a BMS for a remotely-operated-vehicle (ROV) application. This revealed that a 2RC equivalent-electric-circuit (EEC) model provides the required level of accuracy, complexity of implementation and computational cost. Laboratory experiments where performed on a fresh cell in order to extract the parameters of the model. The relationship between open-circuit-voltage (OCV) and SoC was found by curve-fitting a custom function to the voltage data and measured SoC. A highly accurate OCV-SoC function v_{oc}(soc) is found to be crucial to ensure converge to correct SoC and open-circuit voltage, as it is the foundation of the model. The RC parameters is found through nonlinear greybox modelling using the Levenberg-Marquard algorithm. The model has problems fitting the data to 1RC model, so an extra RC-cicrcuit was added. The estimation results showed the parameters expected dependency on SoC. The effect of including this dependency and thereof also complexity was however not found necessary as the RMSE of output voltage only decreased 3.2mV.
The obtained battery model with the respective parameters showed good performance for cell measurement data obtained in the lab experiments. In order to maintain this performance for different operating conditions, a comparative study on different versions of Joint Extended Kalman Filters (JEKF) was performed.
All of the proposed JEKF's performed well in terms of SoC estimation, even for biased current measurements, decreasing total capacity and noise voltage measurements. For SoH estimation through total capacity estimation, a seperate Kalman filter running only at the end of a discharge cycle is suggested. This might be justified because of the operational profile of the ROV which utilize close to full SoC range.
Since total capacity is such a slowly varying process, there is no reason to estimate it every second.
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A novel approach of using SoP as a model-predictive control law saturating maximum power of the battery has been explored. While the accuracy of the SoP estimates are not validated, the concept shows great potential and should be implemented regardless of the choice of SoC/SoH observer
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