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Single hollow fiber SLM extraction of polyamines followed by tosyl chloride derivatization and HPLC determination

Determination of polyamines in biological fluids possesses medical diagnostic relevance. Despite the vast panel of analytical methods developed for polyamines they are not applied in routine clinical usage, mainly due to the time and labor consuming sample preparation step and complicated derivatization. procedures. Thus, new simpler methods are needed. This paper describes a single hollow fiber S

New aspects of voltage-gated calcium channel regulation in pancreatic beta-cells - Relevance for insulin release and type 2 diabetes

Popular Abstract in German Spannungsgesteuerte Kalziumkanäle haben eine große Bedeutung in vielen elektrisch erregbaren Zellen, wie z.B. in Nervenzellen und pankreatischen beta-Zellen. Hier werden sie folgendermaßen aktiviert: In der Nahrung enthaltener Traubenzucker (Glukose) wird nach einer Mahlzeit über den Blutstrom im Körper verteilt und in die beta-Zellen über Glukosetransporter aufgenommen.Voltage-gated Ca2+ channels are essential transducers of cellular signals in many electrically excitable cells. In the pancreatic beta-cell they mediate controlled Ca2+ influx, which is the final trigger for Ca2+ dependent release (exocytosis) of the blood glucose lowering hormone insulin. Several subtypes of voltage-gated Ca2+ channels are known and the L-type has been found to be the main contri

On the Origins of Core-Electron Chemical Shifts of Small Biomolecules in Aqueous Solution: Insights from Photoemission and ab Initio Calculations of Glycine(aq)

The local electronic structure of glycine in neutral, basic, and acidic aqueous solution is studied experimentally by X-ray photoelectron spectroscopy and theoretically by molecular dynamics simulations accompanied by first-principle electronic structure and spectrum calculations. Measured and computed nitrogen and carbon is binding energies are assigned to different local atomic environments, whi

Determination of rate constants for the uptake process involving SO2 and an aerosol particle. A quantum mechanics/molecular mechanics and quantum statistical investigation

We present a combined quantum mechanics/molecular mechanics and quantum statistical investigation of the interactions between a Molecule (SO2) and an aerosol particle including rate constants for the uptake process. A coupled cluster/molecular mechanics method including explicit polarization is used along with a quantum statistical method for calculating sticking coefficients. The importance of th

An underestimated role of precipitation frequency in regulating summer soil moisture

Soil moisture induced droughts are expected to become more frequent under future global climate change. Precipitation has been previously assumed to be mainly responsible for variability in summer soil moisture. However, little is known about the impacts of precipitation frequency on summer soil moisture, either interannually or spatially. To better understand the temporal and spatial drivers of s

In-plane visibility of lesions using breast tomosynthesis and digital mammography

Purpose: The purpose of this work was to evaluate the visibility of simulated lesions in 2D digital mammography (DM) and breast tomosynthesis (BT) images of patients. Methods: Images of the same women were acquired on both a DM system (Mammomat Novation, Siemens Healthcare, Erlangen, Germany) and a BT prototype system adapted from the same type of DM system. Using the geometrical properties of the

Strength Design Methods for Laminated Glass

In this thesis, methods for efficiently determining stresses in laminated glass structures are developed and tested. The laminated glass structures comprise both bolted and adhesive joints. A recently developed finite element is suggested to be suitable for the modeling of laminated glass structures. The element is implemented and tested. It is proven by means of a simple test example that the ele

Life Satisfaction and the Oldest-Old. Results from the longitudinal population study "Good Aging in Skåne".

The overall aim of this thesis was to study life satisfaction (LS) and factors associated to LS in the group aged 78 and above. As an aid in interpreting the findings, Baltes’ and Baltes’ theory of selective optimisation with compensation (SOC) was used. All four studies included the same studypopulation who were followed for three years in the study Good Aging in Skåne, a national, randomized, po

Dynamic Multi-Objective Optimization of Batch Chromatographic Separation Processes

This contribution presents a novel offline dynamic multi-objective optimization framework for high-pressure liquid chromatographic (HPLC) processes in batch elution mode. The framework allows for optimization of general elution trajectories parametrized with piecewise constant control signals. It is based on a simultaneous method where both the control and state variables are fully discretized in

Extremum seeking of dynamical systems via gradient descent and stochastic approximation methods

This paper examines the use of gradient based methods for extremum seeking control of possibly infinite-dimensional dynamic nonlinear systems with general attractors within a periodic sampled-data framework. First, discrete-time gradient descent method is considered and semi-global practical asymptotic stability with respect to an ultimate bound is shown. Next, under the more complicated setting w

Underwater working times in two groups of traditional apnea divers in Asia: the Ama and the Bajau

(Schagatay E, Lodin-Sundstrom A. Abrahamsson E. Underwater working times in two groups of traditional apnea divers in Asia: the Ama and the Bajau. Diving and Hyperbaric Medicine. 2011;41(1):27-30.) Introduction: Traditional apnea diving for sea harvesting for a living continues in some communities in Asia, the outcome being dependent on the total underwater working time. We studied dive and surfac

Nitrogen leaching and ectomycorrhizal nitrogen retention capacity in a Norway spruce forest fertilized with nitrogen and phosphorus

To estimate the production of external ectomycorrhizal mycelia (EMM) in Norway spruce forests with varying nitrogen (N) and phosphorus (P) levels, and to relate this to the N retention capacity of ectomycorrhizal fungi (EMF) and N leaching. Seasonal changes in EMF production (in ingrowth mesh bags) and soil water N (in suction lysimeters) were analyzed after fertilization with N or N combined with

The Professional Landscape: The Historical Development of Professions in Sweden

This special issue of Professions & Professionalism seeks to explain the transition of occupations from non-professions to professions and the conditions and causes that generate professions (i.e., the bases of professionalization). Empirically, we use the histories of the Swedish professions, positing that these histories have several close similarities (and, of course, differences) with thos

Variation of strain in granular GaAs:MnAs layers

Granular GaAs(MnAs) layers with different Mn concentration and various layer thickness were grown by MBE method and subjected to annealing at 500A degrees C under ambient and enhanced hydrostatic pressure. Distinct influence of hydrostatic pressure applied during annealing on strain state of layers as well as on hexagonal MnAs inclusions was found. Pressure induced strain of inclusions is related

Glioma Cell Proliferation Controlled by ERK Activity-Dependent Surface Expression of PDGFRA.

Increased PDGFRA signaling is an essential pathogenic factor in many subtypes of gliomas. In this context the cell surface expression of PDGFRA is an important determinant of ligand sensing in the glioma microenvironment. However, the regulation of spatial distribution of PDGFRA in glioma cells remains poorly characterized. Here, we report that cell surface PDGFRA expression in gliomas is negative

Rare Events in Remote Dark-Field Spectroscopy: An Ecological Case Study of Insects

In this paper, a novel detection scheme for the monitoring of insect ecosystems is presented. Our method is based on the remote acquisition of passive sunlight scattering by two insect species. Procedures to identify rare events in remote dark-field spectroscopy are explained. We further demonstrate how to reduce the spectral representation, and how to discriminate between sexes, using a hierarchi

Nuclear Intonation in Swedish : Evidence from Experimental-Phonetic Studies and a Comparison with German

This thesis investigates Swedish intonation patterns and their interaction with word accent realisation in various pragmatic conditions, using German as a reference language. The point of departure is the wide-spread assumption that Swedish, as a language with a tonal word accent distinction, has a considerably smaller repertoire of nuclear intonation contours than German and other so-called inton

Continuing high early death rate in acute promyelocytic leukemia: a population-based report from the Swedish Adult Acute Leukemia Registry

Our knowledge about acute promyelocytic leukemia (APL) patients is mainly based on data from clinical trials, whereas population-based information is scarce. We studied APL patients diagnosed between 1997 and 2006 in the population-based Swedish Adult Acute Leukemia Registry. Of a total of 3897 acute leukemia cases, 3205 (82%) had non-APL acute myeloid leukemia (AML) and 105 (2.7%) had APL. The in