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Hollow-fibre supported liquid membrane extraction for determination of fluoxetine and norfluoxetine concentration at ultra trace level in sewage samples

In this study, a method was developed for determining the concentration of the pharmaceutical fluoxetine and its metabolite, norfluoxetine, in sewage water samples. Sample preparation was performed by hollow-fibre supported liquid membrane (HF-SLM) extraction with final analysis using liquid chromatography with UV detection. Several parameters were studied including type of organic solvent, sample

A new lower Cambrian eodiscoid trilobite fauna from Swedish Lapland and its implications for intercontinental correlation

A lower Cambrian eodiscoid trilobite fauna and an associated holmiid trilobite, Holmia sp., are described from a bioclastic limestone at the top of the Tornetr¨ask Formation in the Luob´akti section, south of Lake Tornetr¨ask, northern Sweden. Other associated polymerid trilobites include Orodes? lapponica and Strenuaeva inflata. The precise age of the trilobite fauna cannot be determined, but its

Fifteen years of climate change manipulations alter soil microbial communities in a subarctic heath ecosystem

Soil microbial biomass in arctic heaths has been shown to be largely unaffected by treatments simulating climate change with temperature, nutrient and light manipulations. Here, we demonstrate that more than 10 years is needed for development of significant responses, and that changes in microbial biomass are accompanied with strong alterations in microbial community composition. In contrast to sl

In vivo absorption spectroscopy of tumor sensitizers with femtosecond white light

A system based on a femtosecond white-light continuum and a streak camera was used for recordings of the in vivo absorption spectra of the tumor-seeking agent disulphonated aluminum phthalocyanine. Measurements for different drug doses were performed on tumor tissue (muscle-implanted adenocarcinoma) and normal muscle tissue in rats. It was found that the shape of the spectrum is tissue dependent.

The Earthshine Telescope Project

The Earthshine telescope project is a collaborative effort between Lund Observatory (LO) in Sweden and The Institute of Meteorology in Demark (DMI) with the purpose of constructing one or more robotic telescopes to record the albedo of the Earth over a long time. The objective is to measure long-term development of the global cloud coverage and reflectivity for climate modeling. A 1% change in the

Assessment of in vivo MR imaging compared to physical sections in vitro--a quantitative study of brain volumes using stereology

The object of the present study was to compare stereological estimates of brain volumes obtained in vivo by magnetic resonance imaging (MRI) to corresponding volumes from physical sections in vitro. Brains of ten domestic pigs were imaged using a 3-T scanner. The volumes of different brain compartments were obtained from MR images by two observers and from physical sections using the Cavalieri est

Epithelial cells purified from choroid plexus have receptors for vasoactive intestinal polypeptide

Using the choroid plexus from pig a method has been developed to purify the epithelial cells from the underlying vascularized connective tissue stroma. An epithelial cell fraction was obtained that showed a purity of at least 95%, as determined by light microscopic analysis. The epithelial cells were investigated for the presence of binding sites for the neurotransmitter peptide, vasoactive intest

Behavior Modeling by Neural Networks

Modeling of human and animal behavior is of interest for a number of diagnostic purposes. Convolutional neural networks offer a constructive approach allowing learning on a limited number of examples. Chaotic tendencies make that learning is not always successful. The paper looks into a number of applications to find the reason for this anomaly and identifies the need for behavioral references to

Analysis of optothermionic refrigeration based on semiconductor heterojunction

We have examined the theory of optothermionic refrigeration combining the ideas of laser cooling and thermionic cooling [Mal'shukov and Chao, Phys. Rev. Lett. 86, 5570 (2001)] and its estimation on thermal energy extraction by using self-consistent calculations with the drift-diffusion model in this paper. Both the Auger and the Shockley-Read-Hall dissipation processes are considered. For GaAs/AlG

Pollen-tube growth rates in Collinsia heterophylla (Plantaginaceae): one-donor crosses reveal heritability but no effect on sporophytic-offspring fitness

Evolutionary change in response to natural selection will occur only if a trait confers a selective advantage and there is heritable variation. Positive connections between pollen traits and fitness have been found, but few studies of heritability have been conducted, and they have yielded conflicting results. To understand better the evolutionary significance of pollen competition and its potenti

The Bronze Age landscape of the Bjare peninsula, southern Sweden, and its relationship to burial mounds

Palaeoecological analyses from a small fen deposit, combined with pollen analysis from buried soil profiles under prehistoric burial mounds, have been used to investigate the timing and vegetation change associated with the Holocene development of a cultural landscape in southern Sweden. Traditional pollen analysis is complemented with plant macrofossil analysis and soil pollen analysis from withi

Association of Biomarkers With Pre-Radiographically Defined and Radiographically Defined Knee Osteoarthritis in a Population-Based Study

Objective. To evaluate 10 biomarkers in magnetic resonance imaging (M RI)-determined, pre-radiographically defined osteoarthritis (pre-ROA) and radiographically defined OA (ROA) in a population-based cohort of subjects with symptomatic knee pain. Methods. Two hundred one white subjects with knee pain, ages 40-79 years, were classified into OA subgroups according to MRI-based cartilage (MRC) scores

Geographical distribution of allozyme variation in relation to post-glacial history in Carex digitata, a widespread European woodland sedge

Aim To investigate the distribution, and broad-scale geographical patterns, of variation, in the widespread boreo-nemoral woodland herb Carex digitata throughout its native European range. To interpret the revealed geographical pattern of variation in terms of glacial survival, post-glacial migration and inter-regional gene-flow. Location The whole of Europe divided into twenty-five geographical r

Effects of oxygen-sulfur substitution on glycosaminoglycan-priming naphthoxylosides.

Three series of sulfur-containing analogs to the selectively antiproliferative 2-(6-hydroxynaphthyl) β-d-xylopyranoside were synthesized and their biological properties investigated. A short, general route to hydroxynaphthyl disulfides from dihydroxynaphthalenes was developed to utilize the disulfide bond as a sulfur-selective protecting group to enable the orthogonal protection of hydroxyls and t

Molecular properties of the Goodpasture epitope

Goodpasture disease fulfils all criteria for a classical autoimmune disease, where autoantibodies targeted against the non-collagenous domain of the alpha3-chain of collagen IV initiates an inflammatory destruction of the basement membrane in kidney glomeruli and lung alveoli. This leads to a rapidly progressive glomerulonephritis and severe pulmonary hemorrhage. Previous studies have indicated a

Radiative lifetimes of doubly ionized terbium

Radiative lifetimes of two short-lived levels (i.e. 4f(8) (F-7(6))6p(1/2) (6,1/2)(11/2,13/2)) in Tb II are measured by time-resolved laser-induced fluorescence (LIF) technique with a two-step excitation process. Free Tb III ions are produced in a laser-induced plasma. Lifetime values are evaluated with a deconvolution procedure of the time-resolved fluorescence signal with the temporal shape of se

Viral Vector Mediated Overexpression of Human alpha-Synuclein in the Nigrostriatal Dopaminergic Neurons: A New Model for Parkinson's Disease.

Parkinson’s disease is predominantly a dopamine deficiency syndrome, which is produced in the brain by the loss of cells located in a small area in the ventral midbrain called the substantia nigra. Complete unilateral dopamine lesions, based on the administration of toxic substances (ie, 6-hydroxy-dopamine in rats and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in mice and primates) have been ext