Sökresultat

Holocene summer temperature reconstructions from northern Europe based on sedimentary pollen records suggest an onset of peak summer warmth around 9,000 years ago. However, pollen-based temperature reconstructions are largely driven by changes in the proportions of tree taxa, and thus the early-Holocene warming signal may be delayed due to the geographical disequilibrium between climate and tree p

The concentrations of terrestrially derived dissolved organic carbon have been increasing throughout northern aquatic ecosystems in recent decades, but whether these shifts have an impact on aquatic carbon emissions at the continental scale depends on the potential for this terrestrial carbon to be converted into carbon dioxide. Here, via the analysis of hundreds of boreal lakes, rivers and wetlan

The adsorption of Ni, Co, Mn, Ti, and Zr at the (root 2 x root 2)R45 degrees-reconstructed Fe3O4(001) surface was studied by scanning tunneling microscopy, x-ray and ultraviolet photoelectron spectroscopy, low-energy electron diffraction (LEED), and density functional theory (DFT). Following deposition at room temperature, metals are either adsorbed as isolated adatoms or fill the subsurface catio

The selective inhibition (SI) technique has been widely used to resolve fungal and bacterial biomass. By studying bacterial growth (leucine/thymidine incorporation) and respiration simultaneously, this study demonstrates that the inhibitors the SI technique is based on do not efficiently or specifically resolve fungal and bacterial contributions to respiration. At concentrations that completely in

Lakes import organic carbon in the form of dissolved humic substances and other terrigenous compounds. This allochthonous organic carbon is consumed by heterotrophic bacteria, with significant consequences for the biostructure and energy pathways of freshwater ecosystems.

We present a simple and robust technique to retrieve the phase of ultrashort laser pulses, based on a chirped mirror and glass wedges compressor. It uses the compression system itself as a diagnostic tool, thereby making unnecessary the use of complementary diagnostic tools. We used this technique to compress and characterize 7.1 fs laser pulses from an ultrafast laser oscillator. (C)2011 Optical

Inspired by the works of Michel Foucault and Erling Sandmo, this article explores contemporary discourses of military violence against civilians from a genealogical perspective. The purpose is to shed light on the historicity of certain structures of knowledge, thoughts, politics and ethics that are fundamental for the ways in which military violence against civilians is put into words, interprete

Abstract Health studies have repeatedly used air temperature (Ta), sometimes adjusted for humidity, when analyzing the impact of weather on mortality. The aim of this study is to highlight the importance of mean radiant temperature (Tmrt) and its impact on heat related mortality. Tmrt is an essential meteorological parameter that influences the thermal comfort (heat load) of humans. It is useful w

A low-diversity Early Jurassic flora preserved in floodbasin siltstones of the Marburg Subgroup at Inverleigh Quarry in the Clarence-Moreton Basin, eastern Australia, is dominated by Allocladus helgei Jansson sp. nov., a conifer with denticulate leaves tentatively attributed to Araucariaceae. The assemblage also includes Rintoulia variabilis and Caytoniales, (Caytonia cucullata McLoughlin sp. nov.

Using fluorescence super-resolution microscopy we studied simultaneous spectral, spatial localization, and blinking behavior of individual 1D J-aggregates. Excitons migrating 100 nm are funneled to a trap appearing as an additional red-shifted blinking fluorescence band. We propose that the trap is a Frenkel exciton state formed much below the main exciton band edge due to an environmentally induc

The cross section for ep -> eb (b) over barX in photoproduction is measured with the H1 detector at the ep-collider HERA. The decay channel b (b) over bar -> eeX' is selected by identifying the semi-electronic decays of the b-quarks. The total production cross section is measured in the kinematic range given by the photon virtuality Q(2) <= 1 GeV2, the inelasticity 0.05 <= y <= 0.65 and the pseudo

Global climate change increases heat loads in urban areas causing health and productivity risks for millions of people. Inhabitants in tropical and subtropical urban areas are at especial risk due to high population density, already high temperatures, and temperature increases due to climate change. Air conditioning is growing rapidly, especially in South and South-East Asia due to income growth a

Authors such as Dryzek, Gough and Meadowcroft have indicated that social-democratic welfare states could be in a better position to deal with development of the ‘green’ or ‘eco’state, and the intersection of social and environmental policies, than conservative or liberal welfare regimes (synergy hypothesis). However, this hypothesis has as yet not been examined in comparative empirical research. B

Sexual conflict has been proposed to be a mediator of speciation but recent theoretical work, as well as empirical studies, suggests that sexual conflict may also be able to prevent speciation and to preserve genetic polymorphism within a species. Here, we develop a population genetic model and study the effects of sexual conflict in a polymorphic population. The morphs mate assortatively based on

Conditions experienced during embryonic development can have lasting effects, even carrying across generations. Most evidence for transgenerational effects comes from studies of female mammals, with much less known about egg-laying organisms or paternally-mediated effects. Here we show that offspring sex can be affected by the incubation temperature its father experiences years earlier. We incubat

Abstract in Undetermined Background: The performance of glaucoma diagnostic systems could be conceivably improved by the integration of functional and structural test measurements that provide relevant and complementary information for reaching a diagnosis. The purpose of this study was to investigate the performance of data fusion methods and techniques for simple combination of Standard Automate

Popular Abstract in Swedish Alzheimers sjukdom (eng. Alzheimer’s disease, AD) är den vanligaste orsaken till de- mens. Demens innebär en permanent sänkning av intellektuella förmågor som påverkar individen påtagligt i vardagen. Förekomsten av demenssjukdomar ökar betydligt efter 65 års ålder. AD är en långsamt progredierande sjukdom, som oftast börjar med försämrat närminne. Redan idag är AD en beBackground: Alzheimer’s disease (AD) is the most common cause of dementia. In order to have effect of future disease-modifying therapies for AD, the disease must be identified early, before the patients have developed dementia. Many patients with Mild Cognitive Impairment (MCI) have prodromal AD, but other causes for the syndrome are common. No diagnostic method can identify AD in patients with MC

A resonant enhancement of the water-(1)H relaxation rate at three distinct frequencies in the range 0.5-3MHz has been observed in a variety of aqueous biological systems. These so-called quadrupole (Q) peaks have been linked to a dipolar flip-flop polarization transfer from (1)H nuclei to rapidly relaxing amide (14)N nuclei in rotationally immobilized proteins. While the Q-peak frequencies conform