| 1. |
- Huang, Jing-Jia, 1990-
(författare)
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Surface-Controlled Chemical Vapor Deposition of Silicon Carbide
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Polycrystalline cubic silicon carbide, 3C-SiC, has long been investigated in the field of hard coating materials. The typical synthesis method for 3C-SiC coatings is thermal chemical vapor deposition (CVD) using either multicomponent precursors, e.g. methyltrichlorosilane, or a combination of single component precursors, e.g. silane and propane. In this thesis, the fabrication of polycrystalline SiC coatings has been explored from the new aspects on the basis of thermal CVD utilizing silicon tetrachloride (SiCl4) and various hydrocarbons, i.e. toluene (C7H8), methane (CH4) and ethylene (C2H4) as the precursors. The goal of this thesis is to control the surface chemistry in the SiCl4-based SiC CVD and has been accomplished by the following three different approaches: In the first approach to control the surface chemistry of SiC CVD, the difference in the adsorption energy of aromatic and aliphatic hydrocarbons on different SiC crystal planes was utilized. Under identical deposition conditions, a highly <111>-oriented 3C-SiC coating was deposited using C7H8 as the carbon precursor, whereas using CH4 resulted in a randomly oriented 3C-SiC. The results from quantum chemical calculation showed that the active film forming carbon species, i.e. C6H6 in the C7H8 process and CH3 in both C7H8 and CH4 processes, behaved differently when they adsorbed on the 3C-SiC (111) and (110) planes. CH3 is strongly chemisorbed on both planes, while C6H6 is chemisorbed on the (111) plane, but only physiosorbed on the other. The significant difference in the adsorption energy of CH3 and C6H6 on the (111) and (110) planes therefore explains the resulting highly <111>-oriented 3C-SiC from the C7H8 process. Furthermore, the ability to deposit 3C-SiC coatings with alternating highly <111>- and randomly oriented layers by merely switching the carbon precursor between C7H8 and CH4 or C2H4 in a single CVD deposition has further proven that the effect of aromatic hydrocarbons on the preferred growth orientation of 3C-SiC was controlled primarily by the surface chemistry. The second approach to the surface-controlled SiC CVD was based on the reduction of surface reaction probability (β) for conformal film growth via low-temperature, low-pressure CVD, which was originally proposed by Abelson and Girolami. Their strategies in reducing β, including lowering the temperature and increasing the precursor partial pressure, were successfully adapted to the SiC CVD growth using SiCl4 and C2H4 as the precursors in this thesis, where an elevated temperature and a moderate pressure were used. Moreover, the addition of Cl species as a growth inhibitor to the process further reduced the β, leading to a superconformal SiC growth. The third approach employed in this thesis for the SiC growth was pulsed CVD. Instead of a continuous and simultaneous SiCl4 and C2H4 flow, the precursors were pulsed alternately into the chamber with each precursor pulse being separated by a H2 purge. In this precursor delivery mode, the gas phase reactions between SiCl4 and C2H4 were avoided and hence the SiC growth was mostly controlled by the surface chemistry. Altering the pulse durations of the precursors led to a variation of growth per cycle (GPC), which was explained by a two-step mechanism. During the SiCl4 pulse, a thin layer of Si is deposited, which is carburized by carbon species produced during the C2H4 pulse. Additionally, the separation of precursor pulses should lead to a large increase in the surface coverage of Cl species, further enhancing the inhibition effect and resulting in a superconformal SiC growth. By using this approach, superconformal SiC coatings were achieved at temperatures where conventional CVD only yielded nonconformal SiC coatings. The observed decline in coating conformality with an elongated purge implied that more surface Cl species were replaced by H during the H2 purge and consequently the inhibition effect was diminished.
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| 2. |
- Masterton, George, 1978-
(författare)
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Objective Chance : A Study in the Lewisian Tradition
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation explores the notion of objective chance as reasonable degree of belief given what might loosely be called our ultimate evidence. The goal is to develop a notion of objective chance that is broadly Humean: where chance ascriptions are construed as projected, De Dicto, physical modalities. It builds, in large part, on the work of David Lewis on objective chance and the metaphysics of indeterminism. It is argued that Lewis and the sciences take objective chance to measure the degree to which a proposition/sentence is physically determined true. These measures of determinacy are analysed in the Lewisian manner as a special kind of credence, an analysis justified by Lewis’ Principal Principle. This analysis faces several problems: the Principal Principle may not be generally applicable due to vicious circularities, chances so conceived may be incompatible with Humean supervenience, and the analysis itself may be uninformative. This dissertation addresses each of these concerns in turn. It proposes a novel trivial chance solution to the first problem and then extends this to solve the second problem, often referred to as the Bug. The aim of this text with respect to the Bug is not to provide a novel cure, but to increase our understanding of the Bug and why the standard medicine is the best on offer. Toward the end of the dissertation the informativity of the analysis is increased by an in depth study of the analysans. This study culminates in moving from Lewis’ objectified credences to credence conditional on an indexical as the analysans for objective chance.
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| 3. |
- Shakeri Yekta, Sepehr, 1982-
(författare)
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Chemical Speciation of Sulfur and Metals in Biogas Reactors : Implications for Cobalt and Nickel Bio-uptake Processes
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A balanced supply of micronutrients, including metals such as iron (Fe), cobalt (Co), and nickel (Ni), is required for the efficient and stable production of biogas. During biogas formation, the uptake of micronutrient metals by microorganisms is controlled by a complex network of biological and chemical reactions, in which reduced sulfur (S) compounds play a central role. This thesis addresses the interrelationship between the overall chemical speciation of S, Fe, Co, and Ni in relation to the metals bio-uptake processes. Laboratory continuous stirred tank biogas reactors (CSTBR) treating S-rich grain stillage, as well as a number full-scale CSTBRs treating sewage sludge and various combinations of organic wastes, termed co-digestion, were considered. Sulfur speciation was evaluated using acid volatile sulfide (AVS) extraction and S X-ray absorption near edge structure (XANES). The chemical speciation of Fe, Co, and Ni was evaluated through the determination of aqueous metals and metal fractions pertaining to solid phases, as well as kinetic and thermodynamic analyses (chemical speciation modelling). The relative Fe to S content in biogas reactors, which in practice is regulated through the addition of Fe for the purpose of sulfide removal or prior to the anaerobic digestion of sewage sludge, is identified as a critical factor for the chemical speciation and bio-uptake of metals. In the reactors treating sewage sludge, the quantity of Fe exceeds that of S, inducing Fe(II)-dominated conditions under anaerobic conditions, while sulfide dominates in the co-digestion and laboratory reactors due to an excess of S over Fe. Under sulfide-dominated conditions, chemical speciation of the metals is regulated by hydrogen sulfide and the formation of metal sulfide precipitates, which in turn restrict the availability of metals for microorganisms. However, despite the limitations set by sulfide, aqueous concentrations of different Co and Ni species were shown to be sufficient to support metal acquisition by the microorganisms under sulfidic conditions. Comparatively, the concentrations of free metal ions and labile metal-phosphate and -carbonate complexes in aqueous phase, which directly participate in bio-uptake processes, are higher under Fe-dominated conditions. This results in an enhanced metal adsorption on cell surfaces and faster bio-uptake rates. It is therefore suggested that the chemical speciation and potential bioavailability of metals may be controlled through adjustments of the influent Fe concentration in relation to S content. The results also indicated that the pool of metal sulfides in the biogas reactors could be regarded as a source of metals for microbial activities. Thus, the recovery and utilisation of this fraction of metals may be considered as a measure with which to minimise the metal dosing concentrations to CSTBRs.
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| 4. |
- Giri, Suvendu, 1988-
(författare)
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New horizons in string theory : bubble babble in search of darkness
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- It was discovered nearly two decades ago that we live in an accelerating universe that is dominated by dark energy. Understanding the origin of such an energy has turned out to be a very difficult open question in physics, and calls on the need for a fundamental theory like string theory. However, despite decades-long effort, string theory has proven incredibly resilient to a satisfactory construction of dark energy within its framework.In the first part of this thesis and the included papers, we examine this problem and propose two possible solutions. The first is a construction within the framework of M-theory, the eleven dimensional cousin of string theory. Using only well-understood geometric ingredients and higher-derivative corrections to eleven dimensional supergravity, we present a new class of four dimensional vacua that contain dark energy. In the process, we also construct a new class of non-supersymmetric Minkowski vacua that were previously not known. Our second idea is a novel proposal that our universe could be embedded on the surface of an enormous spherical bubble that is expanding in a five dimensional anti de Sitter spacetime. The bubble is made of branes in string theory and its expansion is driven by the difference in the cosmological constants across it. We argued that such a construction arises naturally in string theory, and showed how four dimensional gravity arises in such a universe. We further showed that four dimensional matter and radiation arise from quantities that are innately five dimensional.Another challenging problem in physics concerns the nature of black holes – the presence of an event horizon in particular. This poses a paradox between well understood physical principles, and requires a fundamental theory for its resolution. Towards this goal, we constructed a novel class of horizonless objects that mimics black holes, and proposed these objects as an alternative end point of gravitational collapse. Subsequently, we constructed slowly rotating versions of these "black shells" and proposed an observational signature that could distinguish them from black holes in cosmological experiments. This is discussed in the second part of the thesis and in the included papers.
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| 5. |
- Johansson, Niklas, 1978-
(författare)
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Making Maps and Keeping Logs : Quantum Gravity from Classical Viewpoints
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis explores three different aspects of quantum gravity. First we study D3-brane black holes in Calabi-Yau compactifications of type IIB string theory. Using the OSV conjecture and a relation between topological strings and matrix models we show that some black holes have a matrix model description. This is the case if the attractor mechanism fixes the internal geometry to a conifold at the black hole horizon. We also consider black holes in a flux compactification and compare the effects of the black holes and fluxes on the internal geometry. We find that the fluxes dominate. Second, we study the scalar potential of type IIB flux compactifications. We demonstrate that monodromies of the internal geometry imply as a general feature the existence of long series of continuously connected minima. This allows for the embedding of scenarios such as chain inflation and resonance tunneling into string theory. The concept of monodromies is also extended to include geometric transitions: passing to a different Calabi-Yau topology, performing its monodromies and then returning to the original space allows for novel transformations. All constructions are performed explicitly, using both analytical and numerical techniques, in the mirror quintic Calabi-Yau. Third, we study cosmological topologically massive gravity at the chiral point, a prime candidate for quantization of gravity in three dimensions. The prospects of this scenario depend crucially of the stability of the theory. We demonstrate the presence of a negative energy bulk mode that grows logarithmically toward the AdS boundary. The AdS isometry generators have non-unitary matrix representations like in logarithmic CFT, and we propose that the CFT dual for this theory is logarithmic. In a complementing canonical analysis we also demonstrate the existence of this bulk degree of freedom, and we present consistent boundary conditions encompassing the new mode.
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| 6. |
- Larfors, Magdalena, 1978-
(författare)
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Pierced, Wrapped and Torn : Aspects of String Theory Compactifications
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- An outstanding problem in physics is to find a unified framework for quantum mechanics and general relativity. This is required for a better understanding of black holes and the early cosmology of the universe. String theory provides such a unification. In this thesis, we study aspects of compactifications of type IIB string theory. In the first part of the thesis, we study four-dimensional black holes consisting of D3-branes wrapping cycles in the compact dimensions. We discuss the correspondence between these black holes, topological string theory and matrix models. We then study the influence of black holes on the stability of flux compactifications. In the second part of the thesis, we turn to investigations of the type IIB landscape, i.e. the collection of stable and metastable vacua obtained from flux compactifications on conformal Calabi-Yau manifolds. We show that monodromies are important for the topographic structure of the landscape. In particular we find that there are long series of continuously connected vacua in the complex structure moduli space of the internal manifold. We also use geometric transitions to connect the moduli spaces of different manifolds, and create longer series of vacua. Finally, we investigate the stability of string theory vacua by constructing semiclassical instantons. These results have implications for the population of the landscape by eternal inflation.
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| 7. |
- Palm, Anna, 1969-
(författare)
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Studies on routine inquiry about violence victimization and alcohol consumption in youth clinics
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Objectives: Violence victimization is common in youth, and the association between victimization and ill-health is well established. Youth is also the period when alcohol risk drinking is most prevalent. At youth clinics in Västernorrland, Sweden, a randomized controlled intervention was conducted examining health outcomes and risk drinking after implementing routine inquiry about violence victimization and alcohol consumption.Methods: Participants in the intervention group underwent routine inquiry about violence victimization and alcohol consumption. Victimized participants received empowering strategies and were offered further counseling. Risk drinkers received motivational interviewing (MI). All participants answered questionnaires about sociodemography and health at baseline, at 3 months and at 12 months. Of 1,445 eligible young women, 1,051 (73%) participated, with 54% of them completing the 12-month follow-up. Males were excluded from the quantitative analysis owing to the low number of male participants. Fifteen research interviews examining the experience of routine inquiry were conducted.Results: Violence-victimized young women reported more ill health than non-victimized women did. This was especially evident for those who had been multiply victimized. There were no differences in health outcomes between the baseline and the 12-month follow-up for the intervention group and for the control group. Of the victimized women in the intervention group, 14% wanted and received further counseling. There was a significant decrease in risk drinking from baseline to follow-up, but no differences between the MI group and the controls. There was a large intra-individual mobility in the young women’s drinking behavior.In interviews, the participants described how questions about violence had helped them to process prior victimization. For some, this initiated changes such as leaving a destructive relationship or starting therapy. The participants considered risk drinking in terms of consequences and did not find unit-based guidelines useful.Conclusion: Violence victimization, especially multiple victimization, was strongly associated with ill health in young women. Routine inquiry about violence and subsequent follow-up led to a high degree of disclosure but did not improve self-reported health. However, victimized participants described talking about prior victimization as very helpful. Participants viewed risk drinking in terms of consequences rather than in quantity or frequency of alcohol, which may render unit-based drinking guidelines less useful when addressing risk drinking in youth.
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| 8. |
- Vargas, Sergio C., 1989-
(författare)
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Vacua in String Theory : de Sitter Space and Stability in Flux Compactifications
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Our understanding of cosmology has evolved radically in the last decades. Current models demand the presence of dark energy in our universe and the most favored candidate behind this component is a small positive cosmological constant that characterizes a de Sitter (dS) spacetime. Simultaneously, theoretical physicists have stood up to the challenge of building a consistent theory of quantum gravity and string theory has raised as a strong contender.In this thesis we present some explorations within supergravity, a low energy limit of string theory, studying non-supersymmetric vacua, its stability, and the possibility of finding dS.We study the landscape of flux compactifications to produce dS with non-geometric fluxes. We find precise analytic procedures to find perturbatively stable dS near supersymmetric and no-scale Minkowski in a potential derived from type IIB compactifications. We also provide analytical evidence of naked singularities being produced in supergravity backgrounds after the introduction of anti-Dp-branes, at both vanishing and finite temperature.In order to study the problem of semi-classical stability, we explore compactifications with anti-de Sitter as external space. We argue that truncations to closed-string-sector excitations of non-supersymmetric theories may be non-perturbatively protected by the existence of globally defined fake-superpotentials if they are perturbatively stable, a reasoning that goes in line with the standard positive energy theorems.We find that non-supersymmetric solutions tend to manifest modes with masses under the Breitenlohner-Freedman bound once the open-string-sector is explored while supersymmetric solutions remain stable. We see this as a hint in the nature of the instabilities predicted by the weak gravity conjecture.
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| 9. |
- Blom, Helena, 1970-
(författare)
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Violence exposure among Swedish youth
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- BackgroundViolence is a global public health problem and violence among youth is a matter of high priority. Adolescence and young adulthood are important periods for the foundation of future health. Youth victimization may have serious health consequences, making it important to address the occurrence and socio-medical context for possible interventions against violence.AimsTo analyze prevalence, risk patterns and gender differences in emotional, physical, sexual, and multiple-violence victimizations and the associations between violence victimization and sexual ill health, sexual risk behaviors and mental health in Swedish youth.MethodsA cross sectional study using two samples, a national sample from nine youth health centers in Sweden and a population-based sample from a middle-sized Swedish city. The questionnaire included standardized instruments addressing violence exposure (NorAQ), socio-demographics, mental and sexual ill-health and sexual risk behaviors, alcohol and substance use. Proportions and crude and adjusted odds ratios with a 95% CI were calculated.ResultsA total of 2,250 young women and 920 men, aged 15-23, answered the questionnaire at the youth health centers. In upper secondary school, 1,658 women and 1,589 men, aged 15-22, answered the questionnaire.High prevalence rates with gendered differences both in rates and in co-occurrence of different types of violence were found. Women were more often exposed to emotional violence and sexual violence than men, while men were more often physically victimized. For both women and men, violence victimization before the age of 15 was strongly associated with all types of violence victimizations during the past year.Strong associations were found between multiple-violence victimization and poor mental health in both genders. Among the sexually experienced students, consistent associations between lifetime multiple-violence victimization and various sexual ill-health and sexual risk behaviors were found in both genders, except for non-contraceptive use.ConclusionsHigh prevalence of violence victimization in youth and strong associations between victimization, especially multiple victimization, and poor mental and sexual health were found. This needs to be recognized and addressed in social and medical settings.
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| 10. |
- Domert, Daniel, 1977-
(författare)
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Explorations of University Physics in Abstract Contexts : From de Sitter Space to Learning Space
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This is a thesis which contributes to research in two different fields: theoretical physics and physics education research. The common link between these two research areas is that both involve explorations of abstract physics and mathematical representations, but from different perspectives.The first part of this thesis is situated in theoretical physics. Here a cosmological scenario is explored where a de Sitter phase is replaced with a phase described with a scale factor a(t) ~ tq, where 1/3<1. This scenario could be viewed as an inflationary toy model, and is shown to open up the possibility of an information paradox. This potential paradox is resolved even in the worst case scenario by showing that the time scales involved for such a paradox to occur is of the order of magnitude of the recurrence time for the de Sitter space.The second part of this thesis is situated in physics education research. A number of learning situations that are experienced as abstract by students are explored: probability in one dimensional quantum tunnelling; the mindsets that students adopt towards understanding physics equations used in typical teaching scenarios; and what students focus on when presented with physics equations. The results for the quantum scattering study are four phenomenographic categories of description, for the mind sets study, six epistemological components of mindsets and for the focus on physics equations study, three foci creating five levels of increasing complexity of ways of experiencing physics equations. Pedagogical implications of these results are discussed.
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| 11. |
- Olsson, Martin, 1977-
(författare)
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String Theory at the Horizon : Quantum Aspects of Black Holes and Cosmology
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- String theory is a unified framework for general relativity and quantum mechanics, thus being a theory of quantum gravity. In this thesis we discuss various aspects of quantum gravity for particular systems, having in common the existence of horizons. The main motivation is that one major challenge in theoretical physics today is in trying to understanding how time dependent backgrounds, with its resulting horizons and space-like singularities, should be described in a controlled way. One such system of particular importance is our own universe.We begin by discussing the information puzzle in de Sitter space and consequences thereof. A typical time-scale is encountered, which we interpreted as setting the thermalization time for the system. Then the question of closed time-like curves is discussed in the combined setting where we have a rotating black hole in a Gödel-like universe. This gives a unified picture of what previously was considered as independent systems. The last three projects concerns $c=1$ matrix models and their applications. First in relation to the RR-charged two dimensional type 0A black hole. We calculate the ground state energy on both sides of the duality and find a perfect agreement. Finally, we relate the 0A model at self-dual radius to the topological string on the conifold. We find that an intriguing factorization of the theory previously observed for the topological string is also present in the 0A matrix model.
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| 12. |
- Panizo Pérez, Daniel
(författare)
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Blowing Bubbles from String Theory
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Since the discovery of the accelerated expansion of the universe at the end of the nineties, physicists have tried to describe this cosmological behaviour from theories that are complete in the ultraviolet regime, i.e. theories that are well defined at arbitrarily high energies. The most fundamental property that any proposed model must reproduce is that of a de Sitter space in the lower-dimensional description. In other words, an accelerated expanding four-dimensional cosmology driven by an unknown energy dubbed as dark energy.String theory seems to be the most promising candidate for a theory of quantum gravity, as it naturally accommodates the graviton, the quantum propagator of gravity and fulfills all the requirements to be an ultraviolet-complete theory. However, despite all the efforts of recent decades, no lower-dimensional effective field theory description with the desired positive cosmological constant has yet been obtained. This suspicious conspiracy has motivated the physics community to take a different approach; to investigate what criteria lower-dimensional effective field theories of gauge fields coupled to gravity should satisfy to be derived from string theory rather than aiming to derive four-dimensional effective field theories directly from string theory. One of the most striking conclusions that can be drawn from these criteria is that four-dimensional de Sitter cosmology may belong to the swampland, the set of effective field theories that cannot be obtained from string theory.In the first part of this monograph we will review both classical and quantum approaches to four-dimensional cosmology and then introduce the main aspects and issues faced by the aforementioned string cosmology constructions. The second part of this thesis presents an alternative and novel realisation of a four-dimensional expanding cosmology from string theory. This low-dimensional universe rides a three-dimensional brane that mediates the decay between two different five-dimensional and non-supersymmetric anti-de Sitter vacua. This proposal, known as the Dark Bubble model, turns into advantages some of the liabilities found within the swampland programme, granting an innovative way of realising dark energy from string theory. In this work, we will discuss the top-down construction of the Dark Bubble model from ten-dimensional supergravity, the higher-dimensional origin of four-dimensional dark energy and the new intrinsic hierarchy of energy scales that emerges from this stringy construction. Furthermore, we will also show how four-dimensional matter, radiation and both gravitational and electromagnetic waves will arise naturally from features of the higher-dimensional spacetime.
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| 13. |
- Rajan, Peter, 1974-
(författare)
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Spin-offs from Stretching a Point : Strings, Branes and Higher Spin
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- String theory has proved to be a valuable theoretical laboratory for probing gravity and gauge theory in a unified framework. In this thesis some of the exciting spin-offs of string theory such as branes and higher spin are studied. After a review of the basics of string theory the four papers of the thesis are discussed. In the first paper we support the equivalence between two descriptions of non-commutative open strings by calculating scattering amplitudes in both approaches. The second paper gives a physical interpretation of the fact that Ramond-Ramond charge in string theory on SU(2) is only defined modulo an integer. In the third paper we calculate contributions to the stress-energy tensor of higher-spin theory in four dimensional AdS space, and in the last paper of the thesis we compare the free energy of the two dimesional type 0A extremal blackhole and find agreement with the corresponding quantity in a deformed matrix model.
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| 14. |
- Stenlund, Karin, 1950-
(författare)
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Läsning på mellanstadiet : En studie med fokus på elevers läsförmåga
- 2011
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This study describes the reading ability of 26 middle school students, and the ways in which their reading development is supported in two different classrooms. In order to scrutinize results of students at different reading levels, three focus students were selected.This thesis has four aims. One is to use tests to examine the students’ reading ability as regards their decoding skills and reading comprehension as well as to study other cognitive skills related to reading ability. Another is to describe the students’ reading ability and attitudes towards reading from their own as well as their teachers’ perspectives. A third aim is to analyze how the results of different parts of the study are related to one another. The fourth and final aim is to analyze the classroom activities with a special focus on how reading ability is supported.The study combines quantitative analyses of the students’ reading ability with qualitative analyses of classroom activities. The quantitative sections of the study include various reading tests as well as the teachers’ assessment of the students’ reading development and their answers to selected questions in a student questionnaire concerning their view on reading.The results reveal that several of these students haven´t automated their decoding ability in Grade 4, but that nevertheless most of the students attain their grade level in a reading comprehension test in Grade 4 as well as the goals of a national reading test in Grade 5. However, most of the questions in these two tests require answers that can be explicitly found in the text and do not require any deeper reading comprehension such as inference making for instance. The results also show that these students are unable to assess whether reading is easy for them, but can assess their own reading ability if the purpose is to compare their reading skills with their classmates. The classroom observations indicate that despite quite extensive text work in the classrooms, students who need to develop their decoding abilities receive little support, and that although classroom work focusing on text comprehension is quite frequent, this does not often include deeper levels such as inference making.
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