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  • 1251.
    Adler, Jeremy
    et al.
    Stockholm University, Faculty of Science, Wenner-Gren Institute for Experimental Biology.
    Pagakis,, S
    Parmryd, Ingela
    Stockholm University, Faculty of Science, Wenner-Gren Institute for Experimental Biology.
    Replicate based noise corrected correlation (RBNCC) for accurate measurements of colocalisation.2007Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    Adler. J., Pagakis, S. and Parmryd, I. Replicate based noise corrected correlation (RBNCC) for accurate measurements of colocalisation. The Nordic confocal and advanced microscopy meeting. Fiskebäckskil, Sweden, March 2007

  • 1252.
    Adler, Jeremy
    et al.
    Stockholm University, Faculty of Science, Wenner-Gren Institute for Experimental Biology.
    Pagakis,, S
    Parmryd, Ingela
    Stockholm University, Faculty of Science, Wenner-Gren Institute for Experimental Biology.
    Replicate Based Noise Corrected Correlation (RBNCC) for accurate measurements of colocalization2007Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    Adler, J., Pagakis, S. and Parmryd, I. Replicate Based Noise Corrected Correlation (RBNCC) for accurate measurements of colocalization. The 7th International ELMI Meeting on Advanced Light Microscopy, York, UK, April 2007

  • 1253.
    Adler, Jeremy
    et al.
    Stockholm University, Faculty of Science, Wenner-Gren Institute for Experimental Biology.
    Parmryd, Ingela
    Stockholm University, Faculty of Science, Wenner-Gren Institute for Experimental Biology.
    In support of the Pearson correlation coefficient.2007In: J Microsc, ISSN 0022-2720, Vol. 227, no Pt 1, p. 83; author reply 84-5Article in journal (Refereed)
  • 1254.
    Adler, Jeremy
    et al.
    Stockholm University, Faculty of Science, Wenner-Gren Institute for Experimental Biology.
    Parmryd, Ingela
    Stockholm University, Faculty of Science, Wenner-Gren Institute for Experimental Biology.
    Making accurate measurement of colocalization by correcting for image noise.2007Conference paper (Other (popular science, discussion, etc.))
    Abstract [en]

    Making accurate measurement of colocalization by correcting for image noise. The 51st Biophysical Society Annual Meeting in Baltimore, USA, March 2007

  • 1255.
    Adler, Jeremy
    et al.
    Stockholm University, Faculty of Science, The Wenner-Gren Institute , Cell Biology.
    Parmryd, Ingela
    Stockholm University, Faculty of Science, The Wenner-Gren Institute , Cell Biology.
    Plasma membrane topology and membrane models2009Conference paper (Other academic)
  • 1256.
    Adler, Jeremy
    et al.
    Stockholm University, Faculty of Science, The Wenner-Gren Institute .
    Parmryd, Ingela
    Stockholm University, Faculty of Science, The Wenner-Gren Institute .
    Quantifying Colocalization by Correlation: The Pearson Correlation Coefficient is Superior to the Mander's Overlap Coefficient2010In: CYTOMETRY PART A, ISSN 1552-4922, Vol. 77A, no 8, p. 733-742Article in journal (Refereed)
    Abstract [en]

    The Pearson correlation coefficient (PCC) and the Mander's overlap coefficient (MOC) are used to quantify the degree of colocalization between fluorophores. The MOC was introduced to overcome perceived problems with the PCC. The two coefficients are mathematically similar, differing in the use of either the absolute intensities (MOC) or of the deviation from the mean (PCC). A range of correlated datasets, which extend to the limits of the PCC, only evoked a limited response from the MOC. The PCC is unaffected by changes to the offset while the MOC increases when the offset is positive. Both coefficients are independent of gain. The MOC is a confusing hybrid measurement, that combines correlation with a heavily weighted form of co-occurrence, favors high intensity combinations, downplays combinations in which either or both intensities are low and ignores blank pixels. The PCC only measures correlation. A surprising finding was that the addition of a second uncorrelated population can substantially increase the measured correlation, demonstrating the importance of excluding background pixels. Overall, since the MOC is unresponsive to substantial changes in the data and is hard to interpret, it is neither an alternative to nor a useful substitute for the PCC. The MOC is not suitable for making measurements of colocalization either by correlation or co-occurrence.

  • 1257.
    Adler, Jeremy
    et al.
    Stockholm University, Faculty of Science, The Wenner-Gren Institute, Cell Biology.
    Shevchuk, A
    Novak, P
    Korchev, Y
    Parmryd, I
    Stockholm University, Faculty of Science, The Wenner-Gren Institute, Cell Biology.
    Single Particle Tracking in 2D Produces Gibberish: A Solution2009Conference paper (Other academic)
  • 1258.
    Adler, Maja
    Stockholm University, Faculty of Law, Department of Law.
    Otillbörliga medel: i gränslandet mellan människohandel och koppleri2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 1259. Adler, Niclas
    et al.
    Glassér, Charlotte
    af Klinteberg, Britt
    Stockholm University, Faculty of Social Sciences, Department of Psychology. Centre for Health Equity Studies (CHESS).
    A collaborative research effort to bridge boundaries and support deviant youths in contemporary welfare systems.2005In: European Management Review, ISSN 1740-4754, Vol. 2, no 1, p. 88-99Article in journal (Refereed)
    Abstract [en]

    This paper analyzes the challenges of introducing new approaches to the care of deviant youths in contemporary welfare systems. The specific study of early intervention programs within the area of psychosocial disturbances will be used to explore the interplay between emerging research results and the introduction of new approaches in different functionally specialized welfare carrying organizations. This paper is based on a collaborative research effort between researchers from education, psychology, psychiatry, sociology, economics and business administration and key actors from schools, police, criminal care, social security administrations, municipal health care and municipal politicians and administrative managers. The paper demonstrates that successful introduction of new coping strategies necessitates significant efforts to support the bridging of boundaries, the challenging of legacies and the learning from evidence to change established structures.

  • 1260.
    Adler, Peter
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Studier av geomorfologi på Mani, Peloponnesos, Grekland2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Mani peninsula in the south of Peloponnesos, Greece, is situated only 50 km from the subduction zone of the Hellenic arc. The active, tectonic processes taking place influence the geomorphology of the area. Through the use of remote sensing, analysis of a Digital Terrain Model and a five-day fieldwork study, certain areas of the southern peninsula’s geomorphology were examined for this project including recent processes that create landforms to date. Among those, chemical weathering and tectonics dominate. Also relict landforms were studied to get a greater understanding of the area. Fieldwork resulted in the discovery of two fields of rocks in one of the capes, which most likely were created before the cape underwent uplift to its current level. Also, a conglomerate superimposition of limestone in one of the bays showed indication that great mass movements took place when the surface was lower than today. A pediment is located on the west side of the Sagia Mountain. The asymmetry is probably due to a combination of tectonics and sea level changes.

  • 1261. Adler, Ruth E.
    et al.
    Polyak, Leonid
    Ortiz, Joseph D.
    Kaufman, Darrell S.
    Channell, James E. T.
    Xuan, Chuang
    Grottoli, Andrea G.
    Sellen, Emma
    Stockholm University, Faculty of Science, Department of Geology and Geochemistry.
    Crawford, Kevin A.
    Sediment record from the western Arctic Ocean with an improved Late Quaternary age resolution: HOTRAX core HLY0503-8JPC, Mendeleev Ridge2009In: Global and Planetary Change, ISSN 0921-8181, E-ISSN 1872-6364, Vol. 68, no 02-jan, p. 18-29Article in journal (Refereed)
    Abstract [en]

    Sediment core HLY0503-8JPC raised by the HOTRAX'05 expedition from the Mendeleev Ridge was analyzed for multiple lithological, paleontological. and stable-isotopic proxies to reconstruct paleoceanographic conditions in the western Arctic Ocean during the Late Quaternary. The core, extensively sampled in the upper 5 m, reveals pronounced changes in sedimentary environments during the ca. 250 kyr interval encompassing Marine Isotopic Stages (MIS) 1 to 7. An estimated average resolution of 500 yr/sample, at least for the last glacial cycle including the last interglacial, provides more detail than seen in other sedimentary records from the western Arctic Ocean. The age control is provided by C-14 and amino acid racemization measurements on planktonic foraminifers and correlations with the stratigraphy developed for the central Lomonosov Ridge and with glacial events at the Eurasian Arctic margin. Cyclic variations in lithology combined with foraminiferal abundance and stable-isotopic composition indicate profound changes in hydrographic and depositional environments between interglacial-type and glacial-type periods apparently reflecting a combination of 100-kyr and precessional time scales. This periodicity is complicated by abrupt iceberg- and/or meltwater-discharge events with variable (Laurentide vs. Eurasian) provenance. The proxy record from the interval identified as the last interglacial (MIS 5e), which may aid in understanding the future state of the Arctic Ocean, indicates low ice conditions and possibly enhanced stratification of the water column.

  • 1262.
    Adler, Samuel
    Stockholm University, Faculty of Humanities, Department of English.
    Counterfactuality, Determinism and Free Will in Thomas Hardy’s Tess of the D’Urbervilles, The Mayor of Casterbridge and The Return of the Native.2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis explores the themes of counterfactuality, determinism and free will in Thomas Hardy’s novels Tess of the D’Urbervilles, The Return of the Native and The Mayor of Casterbridge. The aim is to show how some literary strategies create a sensation that the characters are trying to diverge from an anticipated destiny, and how these measures contribute to the impression that the characters possess free will. In other words, Hardy’s literary devices create the notion that the characters are confined but paradoxically they appear independent. The tragic fate and the tragic past of the characters are the two main literary strategies which are investigated in order to show how the characters are confined by the plot, which influences the reader’s perception of the characters. The tragic fate of the character is expressed through the numerous coincidences, the characters’ choices and actions as well as the way the order of events is presented in the narrative. The tragic past is expressed through a history that is assigned to the character or by the events that the character experiences as part of the narrative. Highlighting these literary devices allows for a reading where many of these events have the ability to spark a counterfactual thought in the reader’s mind, an imagined possibility of how a causal chain could have developed differently. I claim that the moment the reader begins to construct a different possible outcome of the plot the feeling that the character has free will is strengthened. This is due to two separate, but related reasons. Firstly, a variety of possible plotlines, caused by counterfactual thinking, strengthens the image of a character with the choice to follow another causal line of events. Secondly. by claiming that the characters take part in creating their fate we are in a way making them responsible for their actions. 

  • 1263.
    Adlercreutz, Martin
    et al.
    Stockholm University, Faculty of Humanities, Department of Media Studies, JMK.
    Enhager, Douglas
    Stockholm University, Faculty of Humanities, Department of Media Studies, JMK.
    Här är vinnarna och förlorarna på nya spellagen2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 1264.
    Adler-Karlsson, Gunnar
    Stockholm University, Faculty of Social Sciences.
    Western economic warfare 1947-1967: a case study in foreign economic policy1968Doctoral thesis, monograph (Other academic)
  • 1265.
    Adlertz, Josefin
    Stockholm University, Faculty of Law, Department of Law.
    Underinstansernas bedömning i nödvärnsfrågor: särskilt beträffande användning av vapen vid försvarsvåld2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 1266.
    Adlerz, Linda
    Stockholm University, Faculty of Science, Department of Neurochemistry.
    Processing of the amyloid precursor protein and its paralogues amyloid precursor-like proteins 1 and 22007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Alzheimer’s disease (AD) is a neurodegenerative disorder which is histopathologically characterised by amyloid plaques and neurofibrillary tangles. Amyloid plaques consist of the amyloid β-peptide (Aβ) that can form aggregates in the brain. Aβ is generated from the amyloid precursor protein (APP) through proteolytic cleavage. APP belongs to a conserved protein family that also includes the two paralogues, APP-like proteins 1 and 2 (APLP1 and APLP2). Despite the immense amount of research on APP, motivated by its implication in AD, the function of this protein family has not yet been determined. In this thesis, we have studied the expression and proteolytic processing of the APP protein family. Our results are consistent with previous findings that suggest a role for APP during neuronal development. Treatment of cells with retinoic acid (RA) resulted in increased synthesis. In addition, we observed that RA treatment shifted the processing of APP from the amyloidogenic to the non-amyloidogenic pathway. The proteins in the APP family have been hard to distinguish both with respect to function and proteolytic processing. However, for development of new drugs with APP processing enzymes as targets this is of great importance. Our studies suggest similarities, but also differences in the mechanism regulating the processing of the different paralogues. We found that brain-derived neurotrophic factor (BDNF) had different impact on the members of the APP family. Most interestingly, we also found that the mechanism behind the increased processing in response to IGF-1 was not identical between the homologous proteins. In summary, our results indicate that in terms of regulation APLP1 and APLP2 differ more from each other than from APP. Our studies open up the possibility of finding means to selectively block Aβ production without interfering with the processing and function of the paralogous proteins.

  • 1267.
    Adlerz, Linda
    et al.
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Beckman, Marie
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Holback, Sofia
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Tehranian, Roya
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Cortés Toro, Veronica
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Iverfeldt, Kerstin
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Accumulation of the amyloid precursor-like protein APLP2 and reduction of APLP1 in retinoic acid-differentiated human neuroblastoma cells upon curcumin-induced neurite retraction2003In: Brain Research. Molecular Brain Research, ISSN 0169-328X, E-ISSN 1872-6941, Vol. 119, no 1, p. 62-72Article in journal (Refereed)
    Abstract [en]

    Amyloid precursor protein (APP) belongs to a conserved gene family, also including the amyloid precursor-like proteins, APLP1 and APLP2. The function of these three proteins is not yet fully understood. One of the proposed roles of APP is to promote neurite outgrowth. The aim of this study was to investigate the regulation of the expression levels of APP family members during neurite outgrowth. We observed that retinoic acid (RA)-induced neuronal differentiation of human SH-SY5Y cells resulted in increased expression of APP, APLP1 and APLP2. We also examined the effect of the NFκB, AP-1 and c-Jun N-terminal kinase inhibitor curcumin (diferuloylmethane) on the RA-induced expression levels of these proteins. We found that treatment with curcumin counteracted the RA-induced mRNA expression of all APP family members. In addition, we observed that curcumin treatment resulted in neurite retraction without any effect on cell viability. Surprisingly, curcumin had differential effects on the APLP protein levels in RA-differentiated cells. RA-induced APLP1 protein expression was blocked by curcumin, while the APLP2 protein levels were further increased. APP protein levels were not affected by curcumin treatment. We propose that the sustained levels of APP and the elevated levels of APLP2, in spite of the reduced mRNA expression, are due to altered proteolytic processing of these proteins. Furthermore, our results suggest that APLP1 does not undergo the same type of regulated processing as APP and APLP2.

  • 1268.
    Adlerz, Linda
    et al.
    Stockholm University, Faculty of Science, Department of Neurochemistry.
    Holback, Sofia
    Stockholm University, Faculty of Science, Department of Neurochemistry.
    Multhaup, Gerd
    Iverfeldt, Kerstin
    Stockholm University, Faculty of Science, Department of Neurochemistry.
    IGF-1-induced Processing of the Amyloid Precursor Protein Family Is Mediated by Different Signaling Pathways2007In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 282, no 14, p. 10203-10209Article in journal (Refereed)
    Abstract [en]

    The mammalian amyloid precursor protein (APP) protein family consists of the APP and the amyloid precursor-like proteins 1 and 2 (APLP1 and APLP2). The neurotoxic amyloid beta-peptide (Abeta) originates from APP, which is the only member of this protein family implicated in Alzheimer disease. However, the three homologous proteins have been proposed to be processed in similar ways and to have essential and overlapping functions. Therefore, it is also important to take into account the effects on the processing and function of the APP-like proteins in the development of therapeutic drugs aimed at decreasing the production of Abeta. Insulin and insulin-like growth factor-1 (IGF-1) have been shown to regulate APP processing and the levels of Abeta in the brain. In the present study, we show that IGF-1 increases alpha-secretase processing of endogenous APP and also increases ectodomain shedding of APLP1 and APLP2 in human SH-SY5Y neuroblastoma cells. We also investigated the role of different IGF-1-induced signaling pathways, using specific inhibitors for phosphatidylinositol 3-kinase and mitogen-activated protein kinase (MAPK). Our results indicate that phosphatidylinositol 3-kinase is involved in ectodomain shedding of APP and APLP1, but not APLP2, and that MAPK is involved only in the ectodomain shedding of APLP1.

  • 1269.
    Adlerz, Linda
    et al.
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Soomets, Ursel
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology. University of Tartu, Estonia.
    Holmlund, Linda
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Virland, Saade
    Langel, Ülo
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Iverfeldt, Kerstin
    Stockholm University, Faculty of Science, Department of Neurochemistry and Neurotoxicology.
    Down-regulation of amyloid precursor protein by peptide nucleic acid oligomer in cultured rat primary neurons and astrocytes2003In: Neuroscience Letters, ISSN 0304-3940, E-ISSN 1872-7972, Vol. 336, no 1, p. 55-59Article in journal (Refereed)
    Abstract [en]

    The amyloid precursor protein (APP) and its proteolytic cleavage products, the amyloid P peptides, have been implicated as a cause of Alzheimer's disease. Peptide nucleic acids (PNA), the DNA mimics, have been shown to block the expression of specific proteins at both transcriptional and translational levels. Generally, the cellular uptake of PNA is low. However, recent studies have indicated that the effect of unmodified antisense PNA uptake is more pronounced in nervous tissue. In this study we have shown that biotinylated PNA directed to the initiator codon region of the APP mRNA (-4 - +11) was taken up into the cytoplasm of primary rat cerebellar granule cells and cortical astrocytes, using fluorescence and confocal microscopy studies. Uptake of PNA was faster in neurons than in astrocytes. Western blotting analysis showed that APP was strongly down-regulated in both neurons and astrocytes. Thus, unmodified PNA can be used for studies on the function of APP in neurons and astrocytes.

  • 1270.
    Adnyani, Desak Putu Deni Putri
    Stockholm University, Faculty of Social Sciences, Department of Education.
    Professional Development for Pre-service Teacher: A Case Study of Professional Development Program for Pre-service Teacher in State University in Central Indonesia2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The present study was a case study which aimed at exploring pre-service teachers’ perceptions of PPG-SM3T program for their professional development. PPG-SM3T program is a professional development program for pre-service teacher in Indonesia. Research design of this study was quantitative design and used convenience sampling. The sample was 60 pre-service teachers who graduated from PPG-SM3T program in a state university in central Indonesia. Instrument used to collect data for the present study was questionnaire and analysis consisted of Principal Component Analysis, Reliability test, and Exploratory Data Analysis were done in order to analyse the data. From the results of analysis, it was found that generally pre-service teachers who took PPG-SM3T program in the mentioned university response positively toward the program. It was found to be very effective for most of them as a preparation to be professional teachers. Workshop and field teaching practice were two features in the program that particularly helpful to prepare them to be professional teacher. However, it was also found that more supervision is needed for pre-service teacher during the program as well as non-teaching activities. Some specific cases also need to be considered for future improvement.

  • 1271. Adolfson, Malin
    et al.
    Laseen, Stefan
    Linde, Jesper
    Svensson, Lars E. O.
    Stockholm University, Faculty of Social Sciences, Institute for International Economic Studies. Stockholm School of Economics, Sweden; NBER, United States.
    Monetary policy trade-offs in an estimated open-economy DSGE model2014In: Journal of Economic Dynamics and Control, ISSN 0165-1889, E-ISSN 1879-1743, Vol. 42, p. 33-49Article in journal (Refereed)
    Abstract [en]

    This paper studies the trade-offs between stabilizing CPI inflation and alternative measures of the output gap in Ramses, the Riksbank's estimated dynamic stochastic general equilibrium (DSGE) model of a small open economy. Our main finding is that the trade-off between stabilizing CPI inflation and the output gap strongly depends on which concept of potential output in the output gap between output and potential output is used in the loss function. If potential output is defined as a smooth trend this trade-off is much more pronounced compared to the case when potential output is defined as the output level that would prevail if prices and wages were flexible.

  • 1272. Adolfson, Malin
    et al.
    Laseen, Stefan
    Linde, Jesper
    Villani, Mattias
    Stockholm University, Faculty of Social Sciences, Department of Statistics.
    Bayesian estimation of an open economy DSGE model with incomplete pass-through2007In: Journal of International Economics, ISSN 0022-1996, E-ISSN 1873-0353, Vol. 72, no 2, p. 481-511Article in journal (Refereed)
    Abstract [en]

    In this paper, we develop a dynamic stochastic general equilibrium (DSGE) model for an open economy, and estimate it on Euro area data using Bayesian estimation techniques. The model incorporates several open economy features, as well as a number of nominal and real frictions that have proven to be important for the empirical fit of closed economy models. The paper offers: i) a theoretical development of the standard DSGE model into an open economy setting, ii) Bayesian estimation of the model, including assessments of the relative importance of various shocks and frictions for explaining the dynamic development of an open economy, and iii) an evaluation of the model's empirical properties using standard validation methods.

  • 1273. Adolfson, Malin
    et al.
    Laseen, Stefan
    Linde, Jesper
    Villani, Mattias
    Stockholm University, Faculty of Social Sciences, Department of Statistics.
    Empirical properties of closed- and open-economy DSGE models of the Euro area2008In: Macroeconomic dynamics (Print), ISSN 1365-1005, E-ISSN 1469-8056, Vol. 12, p. 2-19Article in journal (Refereed)
    Abstract [en]

    In this paper, we compare the empirical proper-ties of closed- and open-economy DSGE models estimated on Euro area data. The comparison is made along several dimensions; we examine the models in terms of their marginal likelihoods, forecasting performance, variance decompositions, and their transmission mechanisms of monetary policy.

  • 1274. Adolfson, Malin
    et al.
    Laséen, Stefan
    Lindé, Jesper
    Svensson, Lars E. O.
    Stockholm University, Faculty of Social Sciences, Institute for International Economic Studies.
    Optimal Money Policy in an Operational Medium-Sized DSGE Model2011In: Journal of Money, Credit and Banking, ISSN 0022-2879, E-ISSN 1538-4616, Vol. 43, p. 1287-1331Article in journal (Refereed)
    Abstract [en]

    We show how to construct optimal policy projections in Ramses, the Riksbank's open-economy medium-sized dynamic stochastic general equilibrium model for forecasting and policy analysis. Bayesian estimation of the parameters of the model indicates that they are relatively invariant to alternative policy assumptions and supports our view that the model parameters may be regarded as unaffected by the monetary policy specification. We discuss how monetary policy, and in particular the choice of output gap measure, affects the transmission of shocks. Finally, we use the model to assess the recent Great Recession in the world economy and how its impact on the economic development in Sweden depends on the conduct of monetary policy. This provides an illustration on how Rames incoporates large international spillover effects.

  • 1275. Adolfson, Malin
    et al.
    Linde, Jesper
    Villani, Mattias
    Stockholm University, Faculty of Social Sciences, Department of Statistics.
    Bayesian analysis of DSGE models: Some comments2007In: Econometric Reviews, ISSN 0747-4938, E-ISSN 1532-4168, Vol. 26, no 2-4, p. 173-185Article in journal (Refereed)
    Abstract [en]

    Sungbae An and Frank Schorfheide have provided an excellent review of the main elements of Bayesian inference in Dynamic Stochastic General Equilibrium (DSGE) models. Bayesian methods have, for reasons clearly outlined in the paper a very natural role to flay in DSGE analysis, and the appeal of the Bayesian paradigm is indeed strongly evidenced by the flood of empirical applications in the area over the last couple of years. We expect their paper to be the natural starting point for applied economists interested in learning about Bayesian techniques for analyzing DSGE models, and as such the paper is likely to have a strong influence on what will be considered best practice for estimating DSGE models. The authors have, for good reasons, chosen a stylized six-equation model to present the methodology. We shall use here the large-scale model in Adolfson et al. (2005), henceforth ALLV, to illustrate a few econometric problems which we have found to be especially important as the size of the model increases. The model in ALLV is an open economy extension of the closed economy model in Christiano et al. (2005). It consists of 25 log-linearized equations, which can be written as a state space representation With 60 state variables, many of them unobserved. Fifteen observed unfiltered time series are used to estimate 51 structural parameters. An additional complication compared to the model in An and Schorfheide's paper is that some of the coefficients in the measurement equation are non-linear functions of the structural parameters. The model is currently the main vehicle for policy analysis at Sveriges Riksbank (Central Bank of Sweden) and similar models are being developed in many other policy institutions, which testifies to the model's practical relevance. The version considered here is estimated on Euro area data over the period 1980Q1-2002Q4. We refer to ALLV for details.

  • 1276. Adolfson, Malin
    et al.
    Linde, Jesper
    Villani, Mattias
    Stockholm University, Faculty of Social Sciences, Department of Statistics.
    Forecasting performance of an open economy DSGE model2007In: Econometric Reviews, ISSN 0747-4938, E-ISSN 1532-4168, Vol. 26, no 04-feb, p. 289-328Article in journal (Refereed)
    Abstract [en]

    This paper analyzes the forecasting performance of an open economy dynamic stochastic general equilibrium (DSGE) model, estimated with Bayesian methods, for the Euro area during 1994Q1-2002Q4. We compare the DSGE model and a few variants of this model to various reduced form forecasting models such as vector autoregressions (VARs) and vector error correction models (VECM), estimated both by maximum likelihood and, two different Bayesian approaches, and traditional benchmark models, e.g., the random. walk. The accuracy of point forecasts, interval forecasts and the predictive distribution as a whole are assessed in, an out-of-sample rolling event evaluation using several univariate and multivariate measures. The results show that the open economy DSGE model compares well with more empirical models and thus that the tension between, rigor and fit in older generations of DSGE models is no longer present. We also critically examine the role of Bayesian model probabilities and other frequently used low-dimensional summaries, e.g., the log determinant statistic, as measures of overall forecasting performance.

  • 1277. Adolfsson Boman, Marianne
    et al.
    Eriksson, Inger
    Stockholm University, Faculty of Social Sciences, Department of Education.
    Hverven, Mona
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Jansson, Anders
    Stockholm University, Faculty of Social Sciences, Department of Special Education.
    Tambour, Torbjörn
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Att introducera likhetstecken i ett algebraiskt sammanhang för elever i årskurs 12013In: Forskning om undervisning och lärande, ISSN 2000-9674, E-ISSN 2001-6131, no 10, p. 29-49Article in journal (Refereed)
    Abstract [sv]

    Artikeln bygger på data från forsknings- och utvecklingsprojektet (FoU) ”Utveckling av matematiskt tänkande – expanderande uppgifter i nybörjarundervisningen” där lärare från Skärsätra skola tillsammans med forskare från Stockholms universitet genomförde ett undervisningsexperiment i syfte att introducera algebra i nybörjarundervisningen.

  • 1278. Adolfsson, E
    et al.
    Shen, Z
    Stockholm University.
    Densification of zirconia-hydroxyapatite ceramics without phase changes2006In: Bioceramics 18 PTS 1 and PTS 2, Vol. 309-311, p. 1141-1144Article in journal (Refereed)
  • 1279.
    Adolfsson, Emma
    Stockholm University, Faculty of Humanities, Department of Language Education.
    Barn, skriftspråk och skola: Fyra lärare i förskoleklass och årskurs 1 berättar om sitt arbete med barns literacyutveckling.2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna uppsats syftar till att belysa och diskutera lärares didaktiska val i arbetet med barns literacyutveckling i förskoleklass respektive årskurs 1. Som grund ligger ett sociokulturellt perspektiv på lärande samt forskning om barns literacyutveckling, och med utgångspunkt i detta samt i min studie har didaktiska val i arbetet med barns literacyutveckling kunnat belysas och diskuteras.

    Inför min studie ställde jag mig den vida forskningsfrågan: Hur arbetar ett par lärare i förskoleklass respektive årskurs 1 i två olika skolor för att befrämja barns literacyutveckling och vilka skäl anger de till detta? Studien bygger på kvalitativa intervjuer med och observationer av fyra olika lärare från två olika skolor, som alla är eller nyligen varit verksamma i förskoleklass eller årskurs 1. I analysen av lärarnas tankar kring arbetet med barns literacyutveckling har olika kategorier vuxit fram, där den mest övergripande, som genomsyrar hela analysen och diskussionen, kom att bli huruvida arbetet med barns literacyutveckling sker i för barnen meningsfulla sammanhang eller ej.

    I min studie framkom det att lärarna delvis arbetar enligt traditionell behavioristisk teori och ett syntetiskt synsätt, men också enligt en modernare sociokulturell teori och ett analytiskt synsätt. Att utgå från en meningsfull helhet, som läsning med meningsinnehåll, eget skrivande samt samtal och lek/dramatisering, och att i detta jobba med de viktiga beståndsdelarna, det vill säga bokstav ljudförhållandet, lyfts fram i detta arbete. Något annat som lyfts fram är hur lärarna individualiserar så att arbetet med barnens literacyutveckling ska bli meningsfullt för eleverna, samt hur de ser på förskoleklassens och årskurs 1:s roll i mötet med eleverna.

  • 1280.
    Adolfsson, Erik
    Stockholm University.
    Phase Stability and Preparations of Oxide-Apatite Composites1999Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the preparation of bioactive composites containing hydroxyapatite, Ca5(PO4)3(OH), and an oxide it has been a problem to prevent the hydroxyapatite from decomposing in the sintering process. This is because H2O is evolved when hydroxyapatite is heated, implying that the occupied OH- positions in hydroxyapatite structure are partly replaced by vacancies and O2- ions. The thermal stability of hydroxyapatite was found to depend on the fraction of vacancies and O2- ions present. The decomposition of the hydroxyapatite is initiated when a critical fraction of the OH- ions has been lost, and it is not specifically related to the temperature applied or atmosphere used. The decomposition temperature of hydroxyapatite and fluoride-containing apatite, Ca5(PO4)3(OH)1-xFx, in the presence of alumina has been studied and found to increase with increasing x value in Ca5(PO4)3(OH)1-xFx. By combining this observation with thermogravimetric studies of hydroxyapatite and Ca5(PO4)3OH1-xFxsamples, it was concluded that the decomposition of hydroxyapatite in the presence of alumina can be described by the following reactions:

    Ca5(PO4)3(OH) --> Ca5(PO4)3(OH)1-xOx/2 + x/2 H20

    2 Ca5(PO4)3(OH)1-xOx/2+ Al2O3 --> 3 Ca3(PO4)2 + CaAl2O4 + (1-x) H2O

    With the use of a closed system for sintering the aluminañapatite composites, the loss of water can be reduced. The equilibrium in the first reaction will then be shifted to the left, and the second reaction will not occur. This implies that a higher sintering temperature can be used to densify an aluminañhydroxyapatite composite. Accordingly, composites of alumina and zirconia, respectively, with hydroxyapatite could be hot isostatically pressed (HIPed) in a closed system at 1200oC and at a pressure of 160 MPa without any detectable decomposition of the hydroxyapatite. Another way to avoid excess formation of vacancies is to replace some of the OH-ions with F-. This implies that the equilibrium in the first reaction given above is shifted to the left, thus improving the thermal stability of the apatite.

    The main result of this thesis work is a more detailed understanding of the reaction between the oxide and hydroxyapatite, which has made it possible to prepare densified oxide-hydroxyapatite composites without decomposition of the hydroxyapatite phase.

  • 1281. Adolfsson, Erik
    et al.
    Shen, Zhijian
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Effects of granule density on strength and granule related defects in zirconia2012In: Journal of the European Ceramic Society, ISSN 0955-2219, E-ISSN 1873-619X, Vol. 32, no 11, p. 2653-2659Article in journal (Refereed)
    Abstract [en]

    A suspension of zirconia powder (TZ3YSE) with a solids loading of 50 vol% was prepared by ball milling. Binders were added and some of the suspension was diluted to 40, 30 and 20 vol% before freeze granulation was performed. A spray dried material (TZ3YSEB) was used as a reference. The pore size distribution of the different granules was evaluated and from the microstructure it was shown that inhomogeneities were present in both the freeze granulated as well as in the spray dried granules. In addition, the density, microstructure as well as the strength of sintered materials prepared from the granules were studied. The results showed that a high green density or sintered density was not sufficient in order to achieve a high strength material. It was further shown that the strength was significantly influenced by the granule density and not by the inhomogeneities found in the granules.

  • 1282.
    Adolfsson, Hans
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Alkene and Imino Reductions by Organocatalysis2008In: Modern Reduction Methods, Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim , 2008, p. 341-361Chapter in book (Refereed)
  • 1283.
    Adolfsson, Hans
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Product Class 2: Epoxides (Oxiranes): Synthesis from Alkenes by Metal-Mediated Oxidation2008In: Houben-Weyl Methods of Molecular Transformations: Compounds with One Saturated Carbon-Heteroatom Bond, Georg Thieme Verlag KG, Stuttgart , 2008, p. 227-276Chapter in book (Refereed)
  • 1284.
    Adolfsson, Hans
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Transition metal-catalyzed epoxidation of alkenes2010In: Modern Oxidation Methods / [ed] Jan-Erling Bäckvall, Weinheim: Wiley-VCH Verlag GmbH & Co. KGaA , 2010, 2, p. 37-84Chapter in book (Other academic)
  • 1285.
    Adolfsson, Herbert
    Stockholm University, Faculty of Humanities.
    Liber epistularum Guidonis de Basochis: edidit et adnotationibus instruxit1969Doctoral thesis, monograph (Other academic)
  • 1286.
    Adolfsson, Johanna
    Stockholm University, Faculty of Social Sciences, Department of Human Geography.
    The Power of the Palestinian Landscape: An exploratory study of the functions of power using aerial image interpretation2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Palestinian region is changing rapidly, with both economic and cultural consequences. One way of approaching this very political process is thru the concept of landscape. By viewing the region as a multiprocessual, dynamic landscape the analysis allows for a holistic read where historical and contemporary projections, interpretations and notions of power are fused. This thesis draws on the scholarly fields of humanistic landscape research and aerial image interpretation as well as theories of orientalism and power. A case study of two regions of the West Bank is performed; interviews and observations provide localized knowledge that is then used in open-access image interpretation. By performing image interpretations this thesis explores the power embedded in mapping and the possible inclinations the development towards open-access geospatial analytic tools could have on the functions of power in the Palestinian landscape. By investigating the spatial configuration of the Palestinian landscape and tracing its roots this thesis finds four major themes that are particularly pivotal in the processual change of the Palestinian landscape: the Israeli/Palestinian time-space, the blurring of the conflict, the dynamics of the frontier region and the orientalist gaze. 

  • 1287.
    Adolfsson, Magnus
    et al.
    Stockholm University, Faculty of Social Sciences, School of Business.
    Escriche Bjare, Mikael
    Stockholm University, Faculty of Social Sciences, School of Business.
    Lindström, Stefan
    Stockholm University, Faculty of Social Sciences, School of Business.
    Aktiv förvaltning: En studie av Sverigefonder och deras performance2001Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studien undersöker fondförvaltares aktivitetsgrad och deras avgifterna i förhållande till fondernas performance. Många förvaltare marknadsför sina fonder som aktivt förvaltade, men uppvisar ett resultat i vår undersökning som lämnar utrymme för diskussion.

  • 1288.
    Adolfsson, Magnus
    et al.
    Stockholm University, Faculty of Social Sciences, School of Business.
    Kjernsvik, Johan
    Stockholm University, Faculty of Social Sciences, School of Business.
    Realoptioner: - i teori och praktik2003Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 1289.
    Adolfsson, Maria
    Stockholm University, Faculty of Humanities, Department of Ethnology, History of Religions and Gender Studies.
    Fäderneslandets kännedom: om svenska ortsbeskrivningsprojekt och ämbetsmäns folklivsskildringar under 1700- och 1800-talet2000Doctoral thesis, monograph (Other academic)
    Abstract [en]

    During the period c. 1720-1900 a large quantity of descriptions of rural areas in Sweden were set down on paper. Some 700 local descriptions were printed at the time or have appeared in print during the twentieth century. The most common geographical unit for local descriptions is the parish. As a rule the author was a public servant, and the clergy in particular were industrious local descriptive writers.

    In part the aim of this thesis is to present the Swedish local description projects and local descriptive literature as a phenomenon of the eighteenth and nineteenth centuries. A further aim is to investigate the way the folklife descriptions which come into most of the local descriptions are constituted for the period c. 1750-1850.

    The local descriptions which form the main object of analysis and discussion in the thesis comprise contemporary delineations which came into being in order to achieve an economic-topographical description of the country, where agriculture and the individual economy of the common man were the focus of attention. These descriptions to a certain extent define the problems the authors associate with the economic life of the countryside and way of life of the population.

    Local descriptions constitute a particular category of geographical delineation and have either come into being on the author's own initiative, in reply to a particular institution or the questionnaire of a particular person, or as an academic dissertation. The authors of local descriptions are in most cases connected with the area they describe. The work was mainly carried out by voluntary effort.

    The idea of the need for a national and methodically organised inventorying of resources associated with the physical environment was the most important reason for undertaking local description projects. These Swedish local descriptions were one of several important cornerstones in the endeavours of the State to increase the population, income from taxes, and welfare in general. Local descriptions constituted materialised visions of optimism for growth, and a better and happier future for the country and its inhabitants, in the modern Sweden which was beginning to emerge in the mid-eighteenth century. Another overall aim was to improve the moral status of the peasantry and promote in them a moral and virtuous way of life. The enlightenment of the common man thereby became a didactic matter, touched on in many local descriptions. This process was not unique to Sweden; corresponding efforts took place in a whole host of other European countries.

    The selection of sixty or so local descriptions studied in this thesis are characterised to a great extent by dualistic tendencies on the part of the public servants in their writings about, and interpretations of, peasant character and the state of the agricultural economy. Descriptions of the noble and exemplary true Swedish peasant faithful to his king, hospitable and honest are combined with descriptions of those same people's immodest consumption of spirits, lack of foresight, inclination to the "superstitious", and pernicious love of material things. In actual fact local descriptive writings consisted of an encounter: on the one side between more abstract and political discourses which contained thoughts of an ideal social organisation and the true nature of a population; while on the other side were the everyday experiences of separate writers vis a vis the qualities and situations of the local peasant population, compiled from their position as objectively observing public servants.

  • 1290.
    Adolfsson, Maya
    Stockholm University, Faculty of Law, Department of Law.
    Våldtäkten - socialt legal men formellt olaglig: en radikalfeministisk analys av sexualstraffrättens förmåga att avhjälpa förtryckande könsmaktsstrukturer2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 1291.
    Adolfsson, Sylwia
    Stockholm University, Faculty of Social Sciences, Department of Human Geography.
    Cykel som en del av den hållbara stadsutvecklingen- En studie om upplevelsen av cykling i Stockholm.2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Främjande av hållbar mobilitet och hållbara transportmedel har under de senaste åren varit ett mål för många länder och städer runt om i världen.  I dagsläget är transporter och transportsystem i bl.a. Stockholm Stad inte hållbara och bidrar till miljöproblem därför finns det ett eftersträvan att fler ska välja cykel som ett transportmedel. Cykel är ett billigt transportmedel i jämförelse med andra och den ger inga upphov till utsläpp. Men främjandet av cykling gynnar inte endast miljön, det bidrar också till ett mer jämställt samhälle. Forskning visar att det finns en potential för att andelen resor med cykel ska öka, trots det är andelen resor med cykel fortfarande mycket färre än med andra transportslag. En faktor som hindrar människor att cykla kan vara den upplevda otryggheten. För att främjandet av de hållbara transportmedel, sådana som cykel ska bli framgångsrik är det viktigt att undersöka var och i vilka situationer som cyklisterna upplever otrygghet, samt vilka åtgärder behövs för att minska otryggheten. Dessa frågor besvaras huvudsakligen med hjälp av enkätundersökning, observation och kompletterande intervjuer. Resultatet för denna studie visar att cyklisterna upplever otrygghet främst på grund av bristande infrastruktur men också brist på hänsyn och samspel bland trafikanter. Det visar sig även att för att minska otryggheten krävs mer än att bara förbättra samt bygga ut cykelinfrastrukturen. Åtgärderna måste även ge förutsättningar för förändring i beteendet bland de olika trafikantgrupper. 

  • 1292.
    Adolfsson, Tomas
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Ledin, Mikael
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    ”Terapi är något man måste göra hela tiden”: Hur psykoterapiklienter i KBT och PDT integrerar och använder sig av erfarenheter från terapin i sin vardag2007Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    I psykoterapidebatten finns två läger, som hävdar gemensamma respektive specifika faktorers betydelse för utfallet i psykoterapi. I forskningen finns brist på studier som lyfter fram klientens subjektiva upplevelse av terapins nytta. Uppsatsens syfte var att undersöka hur psykoterapiklienter integrerar och använder erfarenheter från terapin i sin vardag, samt vilka faktorer som har underlättat terapiprocessen. Tretton klienter som genomgått psykodynamisk terapi (PDT) eller kognitiv beteendeterapi (KBT) intervjuades. Data analyserades tematiskt och sammanställdes som fyra idealtyper. Resultaten visade att gruppen PDT-klienters breda problemformuleringar utvecklades via förändrade tankemönster till konkreta användningsområden. KBT-klienternas avgränsade problemformulering utvecklades via bemästrande av avgränsat problem till generaliserad användning av strategier. Viktiga gemensamma inslag i terapiprocessen var insikt, förmåga att se sig själv utifrån och möjlighet eller vilja till konkret applicering av nya erfarenheter. Underlättande faktorer var klientens beredskap och aktiva deltagande, i kombination med förtroende för terapeuten och tro på terapimodellen. Användning som alternativt utfallsmått diskuteras, liksom resultatens implikationer för terapeutisk verksamhet och synen på utvärdering av psykoterapi.

  • 1293.
    Adolfsson-Erici,
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Allmyr,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Antibakteriellt behandlade konsumentprodukter - källa till exponering av människa och miljö2007Report (Other (popular science, discussion, etc.))
  • 1294.
    Adolfsson-Erici,
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Allmyr,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Andersson, H.
    Glynn, A.
    Sources of triclosan exposure to humans2007In: SETAC News: May 20-24, 2007Conference paper (Other (popular science, discussion, etc.))
  • 1295.
    Adolfsson-Erici,
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Alsberg,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Magnér,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Gunnarsson, L.
    Larsson, D.G.J.
    Pharmacuticals in fish bile2007In: SNMM: March 12-14 2007, 2007Conference paper (Other (popular science, discussion, etc.))
  • 1296.
    Adolfsson-Erici,
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Alsberg,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Magnér,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Gunnarsson, L.
    Larsson, D.G.J.
    Tracing pharmaceutical residues from humans to fish2007In: SETAC News: May 20-24, 2007Conference paper (Other (popular science, discussion, etc.))
  • 1297.
    Adolfsson-Erici, M.
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Pettersson, M.
    Parkkonen, J.
    Sturve, J.
    Triclosan, a commonly used bactericide found in human milk and in the aquatic environment in Sweden2002In: Chemosphere, ISSN 0366-7111, Vol. 46, no 9-10, p. 1485-1489Article in journal (Refereed)
  • 1298.
    Adolfsson-Erici, Margaretha
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Fish bile in environmental analysis2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This work explores the usefulness of fish bile analysis in combination with biomarkers for identifying and evaluating new environmental contaminants in the aquatic environment. It illustrates how bile analysis can be used together with biomarkers to assess the causes of estrogenic effects, to identify chemicals in the aquatic environment that are taken up by fish, and to monitor environmental exposure.

    In a first application, fish exposed to sewage treatment plant effluent were studied. Elevated levels of vitellogenin in the exposed fish demonstrated that estrogenic effects occurred. Several estrogen disrupting substances were identified in the fish bile, and analysis of water samples confirmed that these substances were present in the effluent. The synthetic estrogen 17a-ethinylestradiol, which is known to be present in sewage treatment plant effluent, was shown for the first time to be taken up by fish. Considering the reported potencies of the detected substances, it was concluded that 17a-ethinylestradiol was the major contributor to the estrogenic effects.

    Chemical analysis of bile was used to identify rubber additives that were released from tires immersed in water. The bile of rainbow trout held in the water contained high levels of metabolites of PAHs and aromatic nitrogen compounds. Several biomarkers were also measured in the exposed fish, and EROD induction and oxidative stress were observed. Based on the bile analysis observations together with knowledge of toxicological mechanisms, it was postulated that the EROD induction was due to the PAHs, while aromatic nitrogen compounds caused the oxidative stress.

    Resin acids in fish bile proved to be a good indicator of exposure in a chronic long-term study of rainbow trout exposed to effluent from a total chlorine free (TCF) pulp mill. Elevated levels of GST (gluthatione-S-transferase) and GR (gluthatione reductase) activity, and the presence of DNA adducts after a two month recovery period, indicated that compounds in the pulp mill effluents have persistent effects. In addition to characterising the exposure of the fish to the effluent, the analysis of the resin acids in the bile provided evidence of accidents in the pulp mill that the existing process monitoring system had not detected.

    Resin acids in bile were also found to be a valuable indicator of exposure to pulp mill effluents for eelpout living in the Baltic Sea. A correlation between resin acid levels in bile and skewed sex ratios provided an important link in the chain of evidence that substances in the pulp mill effluents cause male bias of the eelpout embryos.

    A particularly good example of the potential of bile analysis was the identification of a previously unknown environmental contaminant. A large peak was observed in the bile extracts of fish that had been exposed to sewage treatment plant effluent. This peak was identified as triclosan, which demonstrated its presence in sewage treatment plant effluent. Other work went on to show that it is a common contaminant of the aquatic environment. The ability of fish to concentrate contaminant metabolites in bile to levels very much higher than in the environment, and the comparatively low levels of analytic interferences, make bile a particularly attractive matrix to search for new, unknown organic pollutants

  • 1299.
    Adolfsson-Erici, Margaretha
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Åkerman, Gun
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Jahnke, Annika
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Mayer, Philipp
    McLachlan, Michael S.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    A flow-through passive dosing system for continuously supplying aqueous solutions of hydrophobic chemicals to bioconcentration and aquatic toxicity tests2012In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 86, no 6, p. 593-599Article in journal (Refereed)
    Abstract [en]

    A continuous supply of water with defined stable concentrations of hydrophobic chemicals is a requirement in a range of laboratory tests such as the OECD 305 protocol for determining the bioconcentration factor in fish. Satisfying this requirement continues to be a challenge, particularly for hydrophobic chemicals. Here we present a novel solution based on equilibrium passive dosing. It employs a commercially available unit consisting of similar to 16000 polydimethylsiloxane (PDMS) tubes connected to two manifolds. The chemicals are loaded into the unit by repeatedly perfusing it with a methanol solution of the substances that is progressively diluted with water. Thereafter the unit is perfused with water and the chemicals partition from the unit into the water. The system was tested with nine chemicals with logK(ow) ranging from 4.1 to 6.3. The aqueous concentrations generated were shown to be largely independent of the water flow rate, and the unit to unit reproducibility was within a factor of similar to 2. In continuous flow experiments the aqueous concentrations of most of the study chemicals remained constant over 8 d. A model was assembled that allows prediction of the operating characteristics of the system from the logKow or PDMS/water partition coefficient of the chemical. The system is a simple, safe, predictable and flexible tool that generates stable aqueous concentrations of hydrophobic chemicals.

  • 1300.
    Adolfsson-Erici, Margaretha
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Åkerman, Gun
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    McLachlan, Michael S.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Internal Benchmarking Improves Precision and Reduces Animal Requirements for Determination of Fish Bioconcentration Factors2012In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, no 15, p. 8205-8211Article in journal (Refereed)
    Abstract [en]

    The enactment of new chemical regulations has generated a large need for the measurement of the fish bioconcentration factor (BCF). Past experience shows that the BCF determination lacks precision, requires large numbers of fish, and is costly. A new protocol was tested that shortens the experiment from up to 12 weeks for existing protocols to 2 weeks and reduces the number of fish by a factor of 5, while introducing internal benchmarking for the BCF determination. Rainbow trout were simultaneously exposed to 11 chemicals. The BCFs were quantified using one of the test chemicals, musk xylene, as a benchmark. These were compared with BCFs measured in a parallel experiment based on the OECD 305 guideline. The agreement was <20% for five chemicals and between 20%-25% for two further, while two chemicals lay outside the BCF operating window of the experiment and one was lost due to analytical difficulties. This agreement is better than that observed in a BCF Gold Standard Database. Internal benchmarking allows the improvement of the precision of BCF determination in parallel to large reduction in costs and fish requirements.

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