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Beyond graphene : Electrochemical sensors and biosensors for biomarkers detection

Graphene's success has stimulated great interest and research in the synthesis and characterization of graphene-like 2D materials, single and few-atom-thick layers of van der Waals materials, which show fascinating and technologically useful properties. This review presents an overview of recent electrochemical sensors and biosensors based on graphene and on graphene-like 2D materials for biomarke

Dimerization of Terminal Domains in Spiders Silk Proteins Is Controlled by Electrostatic Anisotropy and Modulated by Hydrophobic Patches

The well-tuned spinning technology from spiders has attracted many researchers with the promise of producing high-performance, biocompatible, and yet biodegradable fibers. So far, the intricate chemistry and rheology of spinning have eluded us. A breakthrough was achieved recently, when the 3D structures of the N and C terminal domains of spider dragline silk were resolved and their pH-induced dim

Observation-based estimates of fossil fuel-derived CO2 emissions in the Netherlands using Δ14C, CO and 222Radon

Surface emissions of CO2 from fossil fuel combustion (ΦFFCO2) are estimated for the Netherlands for the period of May 2006-June 2009 using ambient atmospheric observations taken at station Lutjewad in the Netherlands (6°21'E, 53°24'N, 1 m. a.s.l.). Measurements of Δ14C on 2-weekly integrations of CO2 and CO mixing ratios are combined to construct a quasi-continuous proxy record (FFCO2*) from which

CO2, δo2/N2 and APO: Observations from the Lutjewad, Mace Head and F3 platform flask sampling network

We report results from our atmospheric flask sampling network for three European sites: Lutjewad in the Netherlands, Mace Head in Ireland and the North Sea F3 platform. The air samples from these stations are analyzed for their CO2 and O2 concentrations. In this paper we present the CO2 and O2 data series from these sites between 1998 and 2009, as well as the atmospheric potential oxygen (APO). Th

High resolution modeling of CO2 over Europe: Implications for representation errors of satellite retrievals

Satellite retrievals for column CO2 with better spatial and temporal sampling are expected to improve the current surface flux estimates of CO2 via inverse techniques. However, the spatial scale mismatch between remotely sensed CO2 and current generation inverse models can induce representation errors, which can cause systematic biases in flux estimates. This study is focused on estimating these r

Wine ethanol 14C as a tracer for fossil fuel CO2 emissions in Europe : Measurements and model comparison

14C (radiocarbon) in atmospheric CO2 is the most direct tracer for the presence of fossil-fuel-derived CO2 (CO2-ff). We demonstrate the measurement of wine ethanol as a way to determine the relative regional atmospheric CO2-ff concentration compared to a background site ("regional CO2-ff excess") for specific harvest years. The carbon in wine ethanol is directly back traceable to the atmospheric C

Modeling atmospheric CO2 concentration profiles and fluxes above sloping terrain at a boreal site

CO2 fluxes and concentrations were simulated in the planetary boundary layer above subarctic hilly terrain using a three dimensional model. The model solves the transport equations in the local scale and includes a vegetation sub-model. A WMO/GAW background concentration measurement site and an ecosystem flux measurement site are located inside the modeled region at a hilltop and above a mixed bor

Spatial and temporal variability of land CO2 fluxes estimated with remote sensing and analysis data over western Eurasia

The Eurosiberian Carbonflux project was designed to address the feasibility of inferring the regional carbon balance over Europe and Siberia from a hierarchy of models and atmospheric CO2 measurements over the continent. Such atmospheric CO2 concentrations results from the combination of connective boundary layer dynamics, synoptic events, large-scale transport of CO2, and regional surface fluxes

European CO2 fluxes from atmospheric inversions using regional and global transport models

Approximately half of human-induced carbon dioxide (CO2) emissions are taken up by the land and ocean, and the rest stays in the atmosphere, increasing the global concentration and acting as a major greenhouse-gas (GHG) climate-forcing element. Although GHG mitigation is now in the political arena, the exact spatial distribution of the land sink is not well known. In this paper, an estimation of m

The baltic sea experiment baltex : A brief overview and some selected results of the authors

The mechanisms responsible for the transfer of energy and water within the climate system are under worldwide investigation within the framework of the Global Energy and Water Cycle Experiment (GEWEX) to improve the predictability of natural and man-made climate changes at short and long ranges and their impact on water resources. Five continental-scale experiments have been established within GEW

On the validation of the atmospheric model REMO with ISCCP data and precipitation measurements using simple statistics

The regional atmospheric model REMO is used to study the energy and water exchange between surface and atmosphere over the Baltic Sea and its catchment area. As a prerequisite for such studies, the model has to be validated. A major part of such a validation is the comparison of simulation results with observational data. In this study the DX product of the International Cloud Climatology Project

Unpacking resource mobilisation by incumbents for biorefineries: The role of micro-level factors for technological innovation system weaknesses

This paper unpacks resource mobilisation for biorefineries by studying investment decisions of incumbent pulp and paper firms in Sweden and Finland. The analysis highlights that the limited adoption of biorefinery technologies can be attributed to both insufficient abilities (lack of needed competencies and partnerships) and interests (preference for improving existing technologies) by pulp and pa

High Performance LNAs and Mixers for Direct Conversion Receivers in BiCMOS and CMOS Technologies

The trend in cellular chipset design today is to incorporate support for a larger number of frequency bands for each new chipset generation. If the chipset also supports receiver diversity two low noise amplifiers (LNAs) are required for each frequency band. This is however associated with an increase of off-chip components, i.e. matching components for the LNA inputs, as well as complex routing o

Antifungal activities of extracts produced by liquid fermentations of Chilean Stereum species against Botrytis cinerea (grey mould agent)

Extracts obtained from liquid mycelial fermentations of Chilean species of the Stereum genus showed antifungal activity against Botrytis cinerea. Thirty-six strains were evaluated in vivo and in vitro assays, 25 belonging to Stereum hirsutum (Sh) and 11 to Stereum rameale (Sr). Two types of extracts were obtained: EtOAc-extract (liquid phase) and MeOH-extract (mycelial phase). Plate diffusion assa

A European aerosol phenomenology-5 : Climatology of black carbon optical properties at 9 regional background sites across Europe

A reliable assessment of the optical properties of atmospheric black carbon is of crucial importance for an accurate estimation of radiative forcing. In this study we investigated the spatio-temporal variability of the mass absorption cross-section (MAC) of atmospheric black carbon, defined as light absorption coefficient (σap) divided by elemental carbon mass concentration (mEC). σap and mEC have

A European aerosol phenomenology -4 : Harmonized concentrations of carbonaceous aerosol at 10 regional background sites across Europe

Although particulate organic and elemental carbon (OC and EC) are important constituents of the suspended atmospheric particulate matter (PM), measurements of OC and EC are much less common and more uncertain than measurements of e.g. the ionic components of PM. In the framework of atmospheric research infrastructures supported by the European Union, actions have been undertaken to determine and m

Thoracic magnetic resonance venography using Gadofosveset in patients with venous pathology-A comparative study of image quality and inter-rater variability

BACKGROUND: High-quality non-invasive imaging of the deep venous system in the thorax is challenging, but nevertheless required for diagnosis of vascular pathology as well as for patient selection and preoperative planning for endovascular procedures.PURPOSE: To compare the diagnostic quality of Gadofosveset-enhanced thoracic magnetic resonance venography, seven consecutive patients with suspected

Treatment of mesenteric vein thrombosis with transjugular mechanical thrombectomy and subsequent simultaneous arterial and venous thrombolysis

Mesenteric vein thrombosis may induce intestinal ischemia and gangrene. In severe cases, it is necessary to restore venous outflow from the small intestine rapidly. We describe a severe case of mesenteric vein thrombosis that was resolved successfully by mechanical thrombectomy from a transjugular approach followed by selective simultaneous venous and arterial thrombolysis via the superior mesente

FDG-accumulating atherosclerotic plaques identified with 18F-FDG-PET/CT in 141 patients

PURPOSE: The aim of this study was to describe the prevalence of atherosclerotic plaques based on [(18)F]-fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in a large population characterized by high risk of cardiovascular disease.PROCEDURES: One hundred forty-one patients referred to our department for FDG-PET/CT for suspected lung cancer were re-evaluated for a

Time-to-time correlation of high-risk atherosclerotic lesions identified with [(18)F]-FDG-PET/CT

OBJECTIVE: It has been shown that [(18)F]-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) can identify macrophage-rich high-risk atherosclerotic plaques in animal models as well as in patients with atherosclerotic plaques in the carotid arteries. The development of inflamed macrophage-rich plaques over time is not well known. This study was performed to determine t