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Maskinisk darwinism: teknikens naturhistoria hos Samuel Butler och Gilles Deleuze

This paper provides perspectives on the development of an idea of the machine as a living being in the 20th century by looking at the relationship between the writings of Samuel Butler and Gilles Deleuze concerning the evolution of machines as an extension of—and in competition with—the human organism. Ultimately, Butler and Deleuze both describe a mechanical or “machinic" vitalism and evolutionis

Persistent organic pollutants (POP) in a benthic omnivore - A comparison between lake and stream crayfish populations

We investigated the accumulation of PCB and DDT in crayfish populations in 10 streams in southern Sweden. The results were compared with an earlier study on crayfish in lakes from the same area. We found that the concentration of pollutants in crayfish did not differ between the two types of systems. Variation in body burden was higher in stream living crayfish probably because of the higher influ

Anderson localization of a weakly interacting one-dimensional Bose gas

We consider the phase coherent transport of a quasi-one-dimensional beam of Bose-Einstein condensed particles through a disordered potential of length L. Among the possible different types of flow we identified [T. Paul, P. Schlagheck, P. Leboeuf, and N. Pavloff, Phys. Rev. Lett. 98, 210602 (2007)], we focus here on the supersonic stationary regime where Anderson localization exists. We generalize

Impact of low-dose prednisolone on bone synthesis and resorption in early rheumatoid arthritis: experiences from a two-year randomized study

Introduction Patients with rheumatoid arthritis (RA) have an increased frequency of osteoporosis, mainly because of increased bone resorption. Reduction of disease activity is suggested to reduce bone remodelling. It might also be possible that prednisolone treatment could cause this effect because prednisolone has been shown to arrest the development of joint destruction in early RA. Therefore, w

Mechanical Behavior of a Supported Lipid Bilayer under External Shear Forces.

Shear forces from a pressure-driven bulk flow in a microfluidic channel can be used to induce and control the motion of a supported lipid bilayer (SLB) formed on the walls of the channel. We here present a theoretical model that relates the experimentally observed drift velocities of an egg yolk phosphatidylcholine (egg PC) SLB to the hydrodynamic drag force from the bulk flow, the intermonolayer

BIRADS classification in breast tomosynthesis compared to mammography and ultrasonography

This paper presents the Malmo Breast tomosynthesis project The tomosynthesis equipment is described as well as the patient selection and image acquisition. Special fucus is given to one of the studies of the project, which is a comparison of the diagnostic performance between breast tomosynthesis (BT), digital mammography (DM) and ultrasonography (US): tumor classification according to the BIRADS

An imaging system for monitoring receptive field dynamics

The paper describes a computerized method, termed receptive field imaging (RFI), for the rapid mapping of multiple receptive fields and their respective sensitivity distributions. RFI uses random stimulation of multiple sites, in combination with an averaging procedure, to extract the relative contribution from each of the stimulated sites. Automated multi-electrode stimulation and recording, with

An explicit spatial model of yeast microcolony growth

Here we present a single-cell-based model of cell-cell interactions in a growing yeast colony. We examine the influence of multiple factors on the colony morphology and switch to a foraging growth behavior. We find that the cell-growth inhibition by neighboring cells along with polar division growth patterns are the most significant factors driving the exploratory behavior of a colony.

Co-firing - A strategy for bioenergy in Poland?

Biomass provides the largest reduction of carbon dioxide (CO2) emission when it replaces coal, which is the dominating fuel in heat and electricity production in Poland. One means of replacing coal with biomass is to co-fire biofuels in an existing coal-fired boiler. This paper presents an analysis of the strengths and weaknesses of co-firing biofuels in Poland with respect to technical, environme

An analysis of momentum and contrarian anomalies using an orthogonal portfolio approach

We use a latent factor approach to investigate if the momentum and contrarian profits, observed in the US stock market, should be considered as risk premiums or have nonrisk-based explanations. The model is also employed as a benchmark to assess the explanatory power of the traditional asset-pricing models in this context. Our findings show that the profits of the long-run contrarian strategy are

Exocrine pancreatic secretion in pigs fed sow's milk and milk replacer, and its relationship to growth performance

The objective of this study was to quantify and compare the effects of sow’s milk and 2 milk replacer diets (containing clotting or nonclotting protein sources) on exocrine pancreatic secretion, plasma cholecystokinin, and immunoreactive cationic trypsin in pigs. In addition, the relationship between exocrine pancreatic secretion and growth in milk-fed pigs was studied. In a changeover experiment,

Establishing a model of seasonal allergic rhinitis and demonstrating dose-response to a topical glucocorticosteroid

Background: Symptoms of seasonal allergic rhinitis may vary greatly. Hence, for research purposes, there is a need for disease-like models of allergic rhinitis. In a preliminary study, involving 7 days' challenge with allergen, promising symptom consistency was obtained and dose-response to a glucocorticosteroid could, in part, be demonstrated. Objective: To establish this model of seasonal allerg

Biocatalytic polyester acrylation-process optimization and enzyme stability.

An OH-functional polyester has been acrylated via transesterification of ethyl acrylate, catalyzed by Candida antarctica lipase B (CalB) in two different preparations: Novozym(R) 435 and immobilized on Accurel(R) MP1000. The batch process resulted in incomplete acrylation as well as severe degradation of the polyester. A high degree of acrylation was achieved by optimization through the applicatio

Development of microformat imaging microplate and membrane immunoenzyme assays of the herbicide atrazine

A microformat imaging technique in combination with registration of chemiluminescence by a charge-coupled device, CCD camera, were applied for the detection of the herbicide atrazine by two immunoenzyme assay formats - microplate and membrane assays. For the microplate (ELISA) case the detection limit was 95 pg mL(-1), giving a 9.5-fold enhancement in comparison with a traditional colorimetric ass

Epigenetic differences arise during the lifetime of monozygotic twins

Monozygous twins share a common genotype. However, most monozygotic twin pairs are not identical; several types of phenotypic discordance may be observed, such as differences in susceptibilities to disease and a wide range of anthropomorphic features. There are several possible explanations for these observations, but one is the existence of epigenetic differences. To address this issue, we examin

Sex-related differences in the associations between hyperleptinemia, insulin resistance and dysfibrinolysis

The adipocyte-derived hormone leptin is associated with insulin resistance and reduced fibrinolytic status - or dysfibrinolysis - in humans. As leptin associates differentially to the development of cardiovascular disease and diabetes in men and women, we hypothesized that leptin and insulin sensitivity are related to dysfibrinolysis in a sex-dependent manner. Thirty-two men and 40 women were recr

Modulation of immune responses in newborn and adult mice by interferon

Interferon was found to have both suppressive and enhancing effects on the antibody response in newborn and adult mice. Evidence was obtained that these effects are primarily evoked during the initial steps controlling cell proliferation. Stimulation of thymus and spleen cells with a T-cell mitogen was enhanced by low doses and suppressed by high doses of interferon. Treatment of parental spleen c

Reversible changes on computed tomography scans of the brain during induction therapy for acute lymphoblastic leukemia in children

Children with acute lymphoblastic leukemia (ALL) have been shown to develop changes on computed tomography (CT) scans of the brain. These changes are seen both during and after therapy. Some of the results have been contradictory. Nine children with ALL were examined by CT of the brain during induction therapy. All children showed normal CT scans on the day of diagnosis. One month later all had di

Constructing librarians’ information literacy expertise in the domain of nursing

This article investigates negotiations of librarians’ expertise in relation to information literacy at the micro-level, specifically in the domain of nursing education. A qualitative empirical framework is employed. The study draws on 18 semi-structured interviews, 16 with Swedish nursing students, one with a librarian and one with a nursing professor. Three themes on librarians’ expertise emerge