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Search Results: 1 - 10 of 2874 matches for " Terje Gr?ntoft "
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Performance Evaluation for Museum Enclosures. Measurement, Modelling and Mitigation of Pollutant Impact on Objects in Museum Enclosures
Terje Grntoft
E-Preservation Science , 2012,
Abstract: Results of measurement and modelling of pollutant gases inside and outside 11 enclosures used to protect exhibited objects in 10 European museums are presented. Monthly average values for ozone, nitrogen dioxide, formic and acetic acid, temperature and relative humidity inside the enclosures, and yearly average values for the pollutants inside and outside the enclosures are presented for each enclosure. An available pollution impact model was adapted to the use with enclosures. Model calculations are presented for the expected change in concentrations of the oxidizing: ozone and nitrogen dioxide, and acidic: acetic and formic acid, pollutants depending on possible change in the ventilation rate of the enclosures and on inclusion of active carbon absorber to reduce the concentrations. The modelling results are presented as the ‘impact concentration’ of the pollutants by weighing the measured concentrations with their respective recommended levels. In several of the enclosures a clear correlation was observed between temperature and/or relative humidity and the concentration of acetic and formic acid. The modelling showed that all of the enclosures protected against air pollutants, but that only one of the 11 enclosures satisfied the recommended level. The recommended level could be reached for all the enclosures by reducing the ventilation or including active carbon absorber to cover the floor area.
DERIVATION OF A MODEL FOR THE CALCULATION OF IMPACT LOADS OF AIR POLLUTANTS TO PAINTINGS IN MICROCLIMATE FRAMES
Terje Grntoft
E-Preservation Science , 2010,
Abstract: The derivation of a model to evaluate the potential impactof gaseous pollutants on paintings installed in microclimateframes (mc-frames), and some examples of modellingresults, is presented. The model can be used to study howbasic design properties of microclimate frames, such astheir air exchange rate, their volume and/or the inclusion ofabsorbers can affect the pollution fluxes to paintings insidethe frames. The modelling indicated that a magnitudeincrease in air exchange rate from a low level of ~1 d-1can significantly increase the impact of infiltrating pollutants,but will give only a small reduction in the potential impactof the small molecular weight organic acids (i.e. acetic andformic acid) that are emitted inside the frames. The reasonfor this is the small amount of pollutant removed by eachsingle air exchange, as compared to the large internalemission and deposition fluxes of these gases.
AIR QUALITY ASSESSMENT IN CULTURAL HERITAGE INSTITUTIONS USING EWO DOSIMETERS
Susana Lopez-Aparicio,Terje Grntoft,Elin Dahlin
E-Preservation Science , 2010,
Abstract: Since its development, the Early Warning dosimeter forOrganic materials (EWO dosimeter) has been used as botha research and general measurement tool for the evaluationof indoor air quality for preser vation of cultural heritageartefacts. The EWO dosimeter measures the integrateddegradation impact of the environment, comparable to thatobserved on organic materials due to the synergisticeffects of gases (NO2 and O3) and climate (temperature /RH, UV-light).Measurements of impacts of air pollution on EWO dosimeterswere performed in different cultural heritage locationsas part of EU projects, other types of international projectsand as a service to individual institutions. In this study, theindoor air quality in different microenvironments or locationsis assessed based on the results obtained by EWOdosimetry. Correlation between the type of location and thedosimeter results has been obser ved. Indoor locations inhighly polluted cities showed higher dosimeter responsethan more rural locations probably due to more infiltrationof outdoor generated pollutants such as NO2 and O3. In contrast,measurements performed inside enclosures (e.g.showcases / microclimate frames) showed low response ofthe dosimeter and hence low photo-oxidizing effects.
MEASUREMENT OF ORGANIC AND INORGANIC POLLUTANTS IN MICROCLIMATE FRAMES FOR PAINTINGS
Susana López-Aparicio,Terje Grntoft,Marianne Odlyha,Elin Dahlin
E-Preservation Science , 2010,
Abstract: Recent studies have shown that indoor environment inmuseums can pose a risk to cultural heritage objectsdue to adverse effects. Cur rent practice is movingtowards protection of artwor ks such as paintings byplacing them into microclimate fr ames (mc-frames).However, little is known about the effects of enclosingpaintings in such a way. Pollutants can enter mc-framesfrom outside the frame (e.g. NOx) or they can be originatedfrom materials within the frame (e.g. volatileorganic compounds). In this study, pollutant concentrationsof organic (VOCs, acetic and for mic acid,formaldehyde) and inor ganic compounds (NO2, SO2 andO3) were measured for the fir st time both inside and outside15 mc-frames. The results showed that the concentrationof inorganic gases is lower inside the mc-framesthan outside. In contrast, higher concentrations ofpotentially aggressive or ganic compounds, such asacetic and formic acid, toluene, α-pinene, p- and mxylenes,limonene and 3-carene, were measured insidethan outside the frames.
Effects of Air Pollution on Materials and Cultural Heritage: ICP Materials Celebrates 25 Years of Research
Johan Tidblad,Vladimir Kucera,Martin Ferm,Katerina Kreislova,Stefan Brüggerhoff,Stefan Doytchinov,Augusto Screpanti,Terje Grntoft,Tim Yates,Daniel de la Fuente,Ott Roots,Tiziana Lombardo,Stefan Simon,Markus Faller,Lech Kwiatkowski,Joanna Kobus,Costas Varotsos,Chris Tzanis,Linda Krage,Manfred Schreiner,Michael Melcher,Ivan Grancharov,Nadya Karmanova
International Journal of Corrosion , 2012, DOI: 10.1155/2012/496321
Abstract: An overview is given of all results from the International Co-operative Programme on Effects on Materials including Historic and Cultural Monuments (ICP Materials), which was launched in 1985. Since then, about twenty different materials have been exposed repeatedly in a network of test sites consisting of more than twenty sites with an extensive environmental characterisation and more than sixty official reports have been issued. Recent results on trends in corrosion, soiling, and pollution show that corrosion of carbon steel, zinc, and limestone is today substantially lower than 25 years ago, but while corrosion of carbon steel has decreased until today, corrosion of zinc and limestone has remained more or less constant since the turn of the century. Unique data are given on measured HNO3 concentrations from 2002-2003, 2005-2006, and 2008-2009, and the relative average decrease was about the same from 2002-2003 to 2005-2006 as it was from 2005-2006 to 2008-2009. 1. Introduction ICP Materials or “the International Co-operative Programme on Effects on Materials including Historic and Cultural Monuments” was launched in 1985 and had its first Task Force Meeting in March 10-11, 1986, Watford, United Kingdom. Since then, more than sixty reports in the official report series have been issued [1–66]. The history of ICP Materials [67] begins, however, with the history of the Convention on Long-range Transboundary Air Pollution (CLRTAP, LRTAP Convention or simply “the Convention”). In 1979, the Member States of the United Nations Economic Commission for Europe (UNECE) adopted the Convention as a response to acid rain, brought on by contamination of the air, killing forests and lakes even in remote places far from industrial facilities [68]. The Convention has been extended by eight protocols that identify specific measures to be taken by their 51 Parties to cut their emissions of air pollutants [69]. Worth mentioning in this context are the 1985 Protocol on the Reduction of Sulphur Emissions or their Transboundary Fluxes by at least 30 per cent, the 1994 Protocol on Further Reduction of Sulphur Emissions, and the 1999 Protocol to Abate Acidification, Eutrophication and Ground-level Ozone. The last of these is also named the “Gothenburg Protocol” or the “multipollutants/multi-effects protocol”. Already in 1980, Vladimir Kucera was approached by UNECE with a request to provide a short summary of the state of knowledge concerning the effects of sulphur compounds on materials. The reason for selecting Sweden was most likely due to Sweden’s well-received case study
The effects of human disturbance on the activity of wild reindeer in different physical condition
Terje Skogland,Beate Gr?van
Rangifer , 1988,
Abstract: We compared two Norwegian wild reindeer herds, Knutsho in excellent physical condition and Hardangervidda in poor physical condition, before and during disturbance by human hunters in order to test whether physical condition effected foraging strategy under stress. Both herds were being regularly hunted (man had been a natural predator on reindeer since prehistoric time). The well-fed Knutsho animals were ca. 30% larger at the start of the hunting season in late August. Before exposure they foraged less and walked more, i.e. were more selective than the Hardangervidda animals which were in energetically lower condition and foraged significantly more and spent less time moving between habitat patches and less time standing. After exposure to hunters disturbed Knutsho animals aggregated into significantly larger groups than before hunting and stood alert more, while Hardangervidda animals spent the same minimum amount of time foraging but moved significantly more and spent almost no time standing. The frequency of disturbance was not significantly different between the two herds and their speeds of movement after disturbances were similar. The hunter kill success rate was also similar in the two areas. The energetic costs, measured as relative body weight loss during the hunting season, was higher for the initially less well-fed Hardangervidda animals, and higher for both herds compared to that from a less disturbed herd (Forelhogna). We hypothezise that while standing still and alert in aggregated groups is risky, it is still more risky to move, but potentially more rewarding if a better habitat could be found. More well-fed Knutsho animals, which aggregated and stood still, conserved allready stored energy, compatible with a time minimizer risk aversive strategy. The Hardangervidda animals which were in poorer condition increased travelling time to an extent that suggested a risky nutrient miximizer strategy in the phase of stress. Effekter av menneskelige forstyrrelser p aktiviteten til villrein i forskjellig fysisk kondisjon. in Norwegian / Sammendrag: For teste om fysisk kondisjon innvirket p beitestrategien, sammenlignet vi to norske vill-reinflokker, Knutsh i utmerket fysisk kondisjon og Hardangervidda i d rlig fysisk kondisjon f r og etter forstyrrelser av jegere. Begge flokker er regelmessig jaktet p (menneske har v rt naturlig predator p rein siden f rhistorisk tid). De veln rte rein p Knutsh var 30% tyngre enn sine artsfeller p Hardangervidda ved starten av jaktsesongen sent i august. F r jakten beitet de mindre og gikk mer, d.v.s. var
Uptake and Organ Distribution of Feed Introduced Plasmid DNA in Growing or Pregnant Rats  [PDF]
Idun M. Gr?nsberg, Lise Nordg?rd, Kristin Fenton, Beate Hegge, Kaare M. Nielsen, Susan Bardocz, Arpad Pusztai, Terje Traavik
Food and Nutrition Sciences (FNS) , 2011, DOI: 10.4236/fns.2011.24053
Abstract: Fragments of DNA present in food and feed are taken up by the gastrointestinal tract (GIT) of mammals. The extent of uptake varies according to organism, study design and DNA source. This study explores the hypothesis that actively growing, as well as pregnant rats, are more likely to take up DNA from the GIT than mature animals due to the high demand for nutrients for tissue and organ development. Plasmid DNA (pDNA) was added to standard feed for growing, and pregnant rats. The young rats received one pDNA (50 μg) containing meal by gavage. Blood, organ and tissue samples were harvested at 2 h to 3 days post feeding (p.f). The pregnant females were fed pellets containing pDNA (100 μg) daily, starting at day 5 after established pregnancy. Females and foeti were killed at days 7 and 14 of gestation, and pups at the time of weaning. Genomic DNA was analyzed by PCR followed by Southern blot and real-time PCR. A 201 bp target sequence was detected in mesenteric lymph nodes, spleen, liver and pancreas from growing rats 2 h p.f. At 6 h, target DNA was detectable in the kidneys, and at three days p.f. in the liver. Target DNA was not detected in samples from pregnant rats, their foeti or pups. In conclusion, low level of feed introduced DNA could be transiently detected in organs of young, growing rats. However, indications of increased DNA uptake levels in the GIT of growing rats were not found.
The Influence of Optimistic Expectations and Negative Life Events on Somatic Symptoms among Adolescents: A One-Year Prospective Study  [PDF]
Terje Arnfinn Murberg
Psychology (PSYCH) , 2012, DOI: 10.4236/psych.2012.32018
Abstract: This study prospectively examined the main effect of optimism on subsequent somatic symptomatology as well as optimism as moderating factors in the link between negative life events and somatic symptoms in a sample of 198 (111 females, 87 males) students in a Norwegian senior high school. Results from the longitudinal multivariate analyses, indicated that the scores for optimism and negative life events were significantly associated with scores of somatic symptoms at time-point two (T2). Moreover, a significant Optimism × Negative life events interaction was found in predicting somatic symptoms. Implications of these findings are discussed.
The alpha-2A adrenoceptor agonist guanfacine improves sustained attention and reduces overactivity and impulsiveness in an animal model of Attention-Deficit/Hyperactivity Disorder (ADHD)
Terje Sagvolden
Behavioral and Brain Functions , 2006, DOI: 10.1186/1744-9081-2-41
Abstract: The present study tested behavioral effects of guanfacine at doses of 0.075, 0.15, 0.30 and 0.60 mg base/kg i.p. in both male SHRs and their controls, the Wistar Kyoto rat (WKY). ADHD-like behavior was tested with a visual discrimination task measuring overactivity, impulsiveness and inattentiveness.The striking impulsiveness, overactivity, and reduced sustained attention during baseline conditions in the SHR improved by treatment with guanfacine. The most pronounced improvement in SHR behavior was seen following the two highest doses (0.3 and 0.6 mg/kg) of guanfacine when SHR behaviors virtually normalized. The positive effects of the drug were most marked towards the end of the session.The results indicate that guanfacine improved poor noradrenergic modulation of neuronal circuits that involve the frontal lobes in an animal model of ADHD. The present results support the beneficial effects of guanfacine on ADHD behavior reported clinically and experimentally in primate models of frontal function. It is likely that guanfacine improved prefrontal functions in the SHR. It cannot be concluded, however, that the effects of the drug are mediated solely by norepinephrine.Attention-deficit/hyperactivity disorder (ADHD) is currently defined as a cognitive developmental disorder where all clinical criteria are behavioral [1]. Overactivity, impulsiveness, and inattentiveness are presently regarded as the main clinical symptoms.There have been many attempts to explain the origins of ADHD symptoms. A dual-process model [2-5] suggests that less efficient reinforcement processes and deficient extinction of previously reinforced behavior are fundamental to the problems described as response inhibition [6] and poor executive functions [7].ADHD is highly heritable and the genetic and neurobiological causes are likely to reside in brain catecholaminergic systems (for a review see [4]). Most likely, ADHD symptoms are associated with dysregulation of dopaminergic and noradrenergic modu
Impulsiveness, overactivity, and poorer sustained attention improve by chronic treatment with low doses of l-amphetamine in an animal model of Attention-Deficit/Hyperactivity Disorder (ADHD)
Terje Sagvolden
Behavioral and Brain Functions , 2011, DOI: 10.1186/1744-9081-7-6
Abstract: The present study tested the behavioral effects of 0.75 and 2.2 mg l-amphetamine base/kg i.p. in male SHRs and their controls, the Wistar Kyoto rat (WKY). ADHD-like behavior was tested with a visual discrimination task measuring overactivity, impulsiveness and inattentiveness.The striking impulsiveness, overactivity, and poorer sustained attention seen during baseline conditions in the SHR were improved by chronic treatment with l-amphetamine. The dose-response curves were, however, different for the different behaviors. Most significantly, the 0.75 mg/kg dose of l-amphetamine improved sustained attention without reducing overactivity and impulsiveness. The 2.2 mg/kg dose improved sustained attention as well as reduced SHR overactivity and impulsiveness.The effects of l-amphetamine to reduce the behavioral symptoms of ADHD in the SHR were maintained over the 14 days of daily dosing with no evidence of tolerance developing.Attention-deficit/hyperactivity disorder (ADHD) is currently defined as a cognitive developmental disorder where all clinical criteria are behavioral [1]. Overactivity, impulsiveness, and inattentiveness are presently regarded as the main clinical symptoms.There have been many attempts to explain the origins of ADHD symptoms. A dual-process theory [2-5] suggests that less efficient reinforcement processes and deficient extinction of previously reinforced behavior may explain behavioral changes often described as response disinhibition [6] or poor executive functioning [7].ADHD is highly heritable and the genetic and neurobiological causes are likely to reside in brain catecholamines (for a review see [4]). Most likely, ADHD symptoms are associated with reduced post-synaptic efficacy of dopaminergic and noradrenergic modulation of neuronal circuits that involve the frontal lobes [8,9]. Imaging of striatal neuronal networks indicates reduced dopamine efficacy in ADHD [10]. Further, noradrenergic systems are involved in attention processes and prime p
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