Sökresultat

Popular Abstract in Swedish Traditionellt sett har man tänkt sig att gradvisa förändringar i yttre miljöfaktorer leder till lika gradvisa ekosystemförändringar, men vi vet nu att ekosystem som utsätts för mänsklig påverkan eller klimatförändringar kan reagera kraftigt och abrupt genom att ett ekologiskt tröskelvärde överskrids varvid en förändring sker från en stabil ekologisk situation till en anRegime shifts in lake ecosystems can occur in response to both abrupt and continuous climate change, and the imprints they leave in palaeolimnological records allow us to investigate and better understand patterns and processes governing ecological changes on geological time scales. This thesis aims at investigating palaeolimnological records of regime shifts in lakes during the Holocene to explor

1. The massive growth of large, toxic cyanobacteria in eutrophic waters has traditionally been explained by their evolution of defences to herbivorous zooplankton. These conclusions come mostly from studies using the large-bodied cladoceran Daphnia as a grazer model. In contrast, very little is known about the effects of other zooplankters such as copepods and small cladocerans that, unlike Daphni

The limiting accuracy for measuring the location of an optical image is set by diffraction and photon noise, i.e., by the dual wave-particle nature of light. A theoretical expression for the limiting accuracy is derived under idealized conditions and generalized to take into account more realistic circumstances, such as additive noise and finite pixel size. Its application is discussed in relation

The chemical composition and dissociation behaviour of water adsorbed on clean and oxygen pre-covered Pd{111} was studied using high-resolution time-resolved and temperature-programmed X-ray photoelectron spectroscopy. We find that water remains intact at all temperatures up to desorption on the clean surface and at high oxygen coverage(0.69 ML) when a surface oxide is formed. The highest desorpti

This paper presents the Development Policy Evaluation Model (DEVPEM), a new simulation model which captures four critical aspects of rural economies in developing countries: (1) the role of the household as both a producer and a consumer of food crops; (2) high transaction costs of participating in markets; (3) market linkages among heterogeneous rural producers and consumers; (4) the imperfect co

Abstract in UndeterminedThe work presented in this article aims to investigate a PV/T hybrid solar window on a system level. A PV/T hybrid is an absorber on which solar cells have been laminated. The solar window is a PV/T hybrid collector with tiltable insulated reflectors integrated into a window. It simultaneously replaces thermal collectors, PV-modules and sunshade. The building integration lo

he immune response is able to control cytomegalovirus infection in most subjects. However, in some patient groups the virus is not well contained resulting in disease and severe morbidity. The development of efficacious vaccines is therefore a high priority. Antibodies may contribute to protection against disease caused by CMV but the most efficient targets for protective humoral immunity are not

Low-dimensional electronic systems in thermoelectrics have the potential to achieve high thermal-to-electric energy conversion efficiency. A key measure of performance is the efficiency when the device is operated under maximum power conditions. Here we study the efficiency at maximum power, in the absence of phonon-mediated heat flow, of three low-dimensional, thermoelectric systems: a zero-dimen

Background: Irritable bowel syndrome (IBS) and gastrointestinal (GI) dysmotility disorders have a similar clinical picture, although dysmotility disorders require the attention of a specialist. Patients with primary Sjogren's syndrome (pSS) have also been described to suffer from IBS-like symptoms. No objective marker is available to distinguish between the patients. A visual analogue scale has be

Background: The objective was to identify separate cognitive domains in the standard assessment tools (MMSE, ADAS-Cog) and analyze the process of decline within domains during three years in Alzheimer's disease (AD) patients with donepezil treatment. Method: AD patients (n = 421) were recruited from a clinical multi-centre study program in Sweden. Patients were assessed every six months during thr

Melanocortin receptor accessory proteins (MRAPs) modulate signaling of melanocortin receptors in vitro. To investigate the physiological role of brain-expressed melanocortin 2 receptor accessory protein 2 (MRAP2), we characterized mice with whole-body and brain-specific targeted deletion of Mrap2, both of which develop severe obesity at a young age. Mrap2 interacts directly with melanocortin 4 rec

Objective. To explore the influences of discrete positive and negative emotions on cooperation in the context of a social dilemma game. Design. Two controlled studies were undertaken. In Study 1, 69 participants were randomly assigned to an essay emotion manipulation task designed to induce either guilt, joy or no strong emotion. In Study 2, 95 participants were randomly assigned to one of the sam

The intrinsic properties of vertical InAs nanowire (NW) capacitors are investigated. The band structure is simulated using a Schrödinger-Poisson solver, taking the conduction band nonparabolicity into account. This is combined with a distributed RC model to simulate the current-voltage characteristics. It is found that the influence from the nonparabolicity is substantial for devices with a small

The suppressor of cytokine signaling (SOCS) family of proteins are well known negative regulators of cytokine receptors signaling consisting of eight structurally similar proteins, SOCS1-7 and CIS. A key feature of this family of proteins is the presence of two structural motifs: a centrally located SH2 domain and a SOCS box in the C-terminus. The SOCS box mediates the interaction with the Elongin

The ALICE Collaboration at the LHC reports measurement of the inclusive production cross section of electrons from semi-leptonic decays of beauty hadrons with rapidity |y| < 0.8 and transverse momentum 1 < p(T)< 10 GeV/c, in pp collisions at root s = 2.76 TeV. Electrons not originating from semi-electronic decay of beauty hadrons are suppressed using the impact parameter of the corresponding track

BACKGROUND: Understanding the role that urologic disease plays within central Haiti could lead to the development of sustainable and regionally appropriate urologic care. We aim to document the prevalence of urologic surgical disease presenting for treatment in central Haiti. METHODS: The present study is based on a retrospective review of surgical case logs at five Partners in Health and Zanmi La

Chronic neural interfaces that are both structurally and functionally stable inside the brain over long time periods and that have minimal effects on the physiological conditions of the neural tissue to be studied hold great promise to become invaluable research and clinical tool in the near future. In this chapter, I will briefly review the state of the art of neural interfaces and the concepts b

Time-dependent changes in the surface properties of coated papers were studied as the evolution of surface hydrophobicity of laboratory and commercially coated papers. We measured the apparent contact angles on the papers during several weeks post-production. Hydrophobicity upon aging increased for all samples made from traditional coating colors on mechanical base stock and on base stock made fro