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"Det är i alla fall mitt barn!" : En studie om att vara missbrukare och mamma skild från barn

The purpose of this study is to let a group of addicted mothers who live separated from their children voice their thoughts and experiences through in-depth interviews made in the early 90's. From a perspective of experience of life we look at their living conditions, their everyday life, their experiences of pregnancy, their life with the children, and their life after the separation. What does i

A Comparative Evaluation of Human Motion Planning Policies

A recently proposed approach to human intention estimation in goal-oriented motion is further improved in this paper. The main features of the approach are the fact that the unicycle model has been rewritten with the natural coordinate as the independent variable, avoiding the explicit dependence from the walking velocity and lowering the number of input variables to one, the proposal of a novel c

A biological approach to salinized soil amelioration in arid Northwest China – Saline water irrigated trees and shrubs on saline sodic soil

A field experiment was carried out to explore the possibilities of planting halophytes on salt-affected land with saline water irrigation. The changes in the salinity of the soil profile, the survival rate and growth conditions as well as the salt tolerance were investigated over a five-year period after the planting of halophyte shrubs and arbours. The results show that halophytes can assimilate

Soil moisture variation and water consumption of spring wheat and their effects on crop yield under drip irrigation

A field study for the arid northwest China has been conducted to find water-saving strategies of drip irrigation for dense-planted crops. The annual water consumption for optimal growth was 420 mm, of which soil evaporation was 27% and the foliage transpiration 73%. A relationship between soil water consumption and the irrigation amount, crop yield and water use efficiency were established. It was

Influence of Quantum Interference on the Thermoelectric Properties of Molecular Junctions

Molecular junctions offer unique opportunities for controlling charge transport on the atomic scale and for studying energy conversion. For example, quantum interference effects in molecular junctions have been proposed as an avenue for highly efficient thermoelectric power conversion at room temperature. Toward this goal, we investigated the effect of quantum interference on the thermoelectric pr

Characterizing gravitational instability in turbulent multicomponent galactic discs

Gravitational instabilities play an important role in galaxy evolution and in shaping the interstellar medium (ISM). The ISM is observed to be highly turbulent, meaning that observables like the gas surface density and velocity dispersion depend on the size of the region over which they are measured. In this work, we investigate, using simulations of Milky Way-like disc galaxies with a resolution

Galaxies that shine : Radiation-hydrodynamical simulations of disc galaxies

Radiation feedback is typically implemented using subgrid recipes in hydrodynamical simulations of galaxies. Very little work has so far been performed using radiation-hydrodynamics (RHD), and there is no consensus on the importance of radiation feedback in galaxy evolution. We present RHD simulations of isolated galaxy discs of different masses with a resolution of 18 pc. Besides accounting for s

Environmental regulation of cloud and star formation in galactic bars

The strong time-dependence of the dynamics of galactic bars yields a complex and rapidly evolving distribution of dense gas and star forming regions. Although bars mainly host regions void of any star formation activity, their extremities can gather the physical conditions for the formation of molecular complexes and mini-starbursts. Using a sub-parsec resolution hydrodynamical simulation of a Mil

Larson's scaling laws, and the gravitational instability of clumpy discs at high redshift

Gravitational instabilities play a primary role in shaping the clumpy structure and powering the star formation activity of gas-rich high-redshift galaxies. Here, we analyse the stability of such systems, focusing on the size and mass ranges of unstable regions in the disc. Our analysis takes into account the mass-size and linewidth-size scaling relations observed in molecular gas, originally disc

The Smith Cloud and its dark matter halo : Survival of a galactic disc passage

Under conservative assumptions about the Galaxy, the derived velocity of the Smith Cloud indicates that it will have undergone at least one passage of the Galactic disc. Using hydrodynamicsimulations, we examine the present-day structure of the Smith Cloud and find that a dark matter supported cloud is able to reproduce the observed present-day neutral hydrogen mass, column density distribution an

The AGORA high-resolution galaxy simulations comparison project

We introduce the Assembling Galaxies Of Resolved Anatomy (AGORA) project, a comprehensive numerical study of well-resolved galaxies within the ΛCDM cosmology. Cosmological hydrodynamic simulations with force resolutions of 100 proper pc or better will be run with a variety of code platforms to follow the hierarchical growth, star formation history, morphological transformation, and the cycle of ba

Large-scale galactic turbulence : Can self-gravity drive the observed H i velocity dispersions?

Observations of turbulent velocity dispersions in the H i component of galactic discs show a characteristic floor in galaxies with low star formation rates and within individual galaxies the dispersion profiles decline with radius. We carry out several high-resolution adaptive mesh simulations of gaseous discs embedded within dark matter haloes to explore the roles of cooling, star formation, feed

A systematic look at the effects of radiative feedback on disc galaxy formation

Galaxy formation models and simulations rely on various feedback mechanisms to reproduce the observed baryonic scaling relations and galaxy morphologies. Although dwarf galaxy and giant elliptical properties can be explained using feedback from supernova and active galactic nuclei, Milky Way-sized galaxies still represent a challenge to current theories of galaxy formation. In this paper, we explo

Simulations of disk galaxies with cosmic ray driven galactic winds

We present results from high-resolution hydrodynamic simulations of isolated Small Magellanic Cloud (SMC)- and Milky-Way-sized galaxies that include a model for feedback from galactic cosmic rays (CRs). We find that CRs are naturally able to drive winds with mass loading factors of up to ∼10 in dwarf systems. The scaling of the mass loading factor with circular velocity between the two simulated s

The formation of disc galaxies in a ΛCDM universe

We study the formation of disc galaxies in a fully cosmological framework using adaptive mesh refinement simulations. We perform an extensive parameter study of the main subgrid processes that control how gas is converted into stars and the coupled effect of supernovae feedback. We argue that previous attempts to form disc galaxies have been unsuccessful because of the universal adoption of strong

Resolving mixing in smoothed particle hydrodynamics

Standard formulations of smoothed particle hydrodynamics (SPH) are unable to resolve mixing at fluid boundaries. We use an error and stability analysis of the generalized SPH equations of motion to prove that this is due to two distinct problems. The first is a leading order error in the momentum equation. This should decrease with an increasing neighbour number, but does not because numerical ins

A dark matter disc in the milky way

Dark matter direct detection experiments need to know the local phase space density of dark matter fdm(r,v,t) in order to derive dark matter particle properties. To date, calculations for fdm(r,v,t) have been based on simulations that model the dark matter alone. Here we include the influence of the baryonic matter. We find that a star/gas disc at high redshift (z∼1) causes merging satellites to b

Systematic uncertainties in the determination of the local dark matter density

A precise determination of the local dark matter density and an accurate control over the corresponding uncertainties are of paramount importance for dark matter (DM) searches. Using very recent high-resolution numerical simulations of a Milky Way like object, we study the systematic uncertainties that affect the determination of the local dark matter density based on dynamical measurements in the

A Toomre-like stability criterion for the clumpy and turbulent interstellar medium

We explore the gravitational instability of clumpy and turbulent gas discs, taking into account the Larson-type scaling laws observed in giant molecular clouds (GMCs) and H i, as well as more general scaling relations. This degree of freedom is of special interest in view of the coming high-z interstellar medium surveys and is thus potentially important for understanding the dynamical effects of t

Discreteness effects in ACDM simulations : A wavelet-statistical view

The effects of particle discreteness in N-body ACDM simulations are still an intensively debated issue. In this paper we explore such effects, taking into account the scatter caused by the randomness of the initial conditions and focusing on the statistical properties of the cosmological density field. For this purpose, we run large sets of ACDM simulations and analyze them using a wide variety of