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A new method for quantification of image distortion due to pile-up in scintillation cameras

Characterization of the count-rate performance of scintillation cameras should include not only the specification of count losses. At high count rates, there is also an image distortion due to the mispositioning of pile-up events. In this paper a simple and clinically relevant procedure to quantify this distortion is presented. The images of a square uniform technetium-99m phantom at high and low

Effects of propofol on ipecacuanha-induced nausea and vomiting

BACKGROUND: The purpose of this study was to evaluate if propofol has 5-HT3 antagonistic effects. Ipecacuanha is known to release serotonin (5-HT) in the gastrointestinal tract and therefore ipecacuanha syrup was used to induce nausea and vomiting. The 5-HT3 antagonist ondansetron was used as a control substance. METHOD: Ten healthy male volunteers (20-37 years) were studied on three occasions and

Long-term treatment with inhaled budesonide in persons with mild chronic obstructive pulmonary disease who continue smoking. European Respiratory Society Study on Chronic Obstructive Pulmonary Disease

BACKGROUND: Although patients with chronic obstructive pulmonary disease (COPD) should stop smoking, some do not. In a double-blind, placebo-controlled study, we evaluated the effect of the inhaled glucocorticoid budesonide in patients with mild COPD who continued smoking. After a six-month run-in period, we randomly assigned 1277 subjects (mean age, 52 years; mean forced expiratory volume in one

Separation of hemicellulosic oligomers from steam-treated spruce wood using gel filtration

Interest in the use of renewable raw materials for the production of various compounds that can replace fossil-based products is steadily increasing. In this study, the extraction and separation of hemicellulosic oligomers from spruce, to be used for the production of polymers such as hydrogels, was investigated. The focus of the study was on gel filtration of the solution from steam treatment of

Rapid lymphocyte reconstitution of unconditioned immunodeficient mice with non-self-renewing multipotent hematopoietic progenitors

The replacement of abnormal hematopoietic stem cells (HSCs) with normal transplanted HSCs can correct a wide range of hematologic disorders. Here, we provide evidence that transplantation of more differentiated progenitor cells can be used to more rapidly correct lymphoid deficiencies in unconditioned immunocompromised mice. Transplantation of flk2+ multipotent progenitors led to robust B and T ce

Heat extraction of corn fiber hemicellulose

Water-soluble hemicellulose was extracted from corn fiber with microwave-assisted heat treatment. The effects of treatment temperature and initial pH of the aqueous extraction media were investigated regarding hemicellulose recovery and molecular mass of the isolated polysaccharides. In treatments carried out at neutral pH (simple water extraction), it has been demonstrated that hemicellulose reco

Influence of plasmons on terahertz conductivity measurements

Time-domain terahertz spectroscopy allows measuring the complex conductivity spectrum of materials at frequencies on the order of 1 THz. Typically, terahertz (THz) studies produce conductivity spectra that are different from those predicted by the classical Drude model, especially in nanostructured materials. We claim that plasmon resonances in particles that are small compared to the THz waveleng

Dyslipoproteinemic changes in borderline hypertension

The present study examined plasma lipoprotein, lipoprotein lipase, hepatic lipase, and insulin levels in men with borderline hypertension (diastolic blood pressure 85 to 94 mm Hg) compared with age-matched normotensive control subjects (diastolic blood pressure less than or equal to 80 mm Hg, n = 75 + 75). High-density lipoprotein (HDL) subclasses were determined in a subset (n = 45 + 45). While t

Membrane cleaning - a case study in a sulphite pulp mill bleach plant

A study was performed. to evaluate the cleaning and operation of the ultrafiltration plant at the Nymolla paper mill in southern Sweden Laboratory tests were carried out in order to find out what the fouling layer consists of and to find the most appropriate cleaning procedure Production data were analysed to establish if the membranes are cleaned unnecessarily often The fouling in the plant is ma

The influence of the thermosiphon effect on the thermal response test

The issue of natural and forced groundwater movements, and its effect on the performance of ground heat exchangers is of great importance for the design and sizing of borehole thermal energy systems (BTESs). In Scandinavia groundwater filled boreholes in hard rock are commonly used. In such boreholes one or more intersecting fractures provide a path for groundwater flow between the borehole and th

The Janus role of c-Jun: Cell death versus survival and regeneration of neonatal sympathetic and sensory neurons

We investigated the functional outcome of c-Jun activation in sympathetic and sensory neurons of neonatal rat superior cervical ganglion (SCG) and dorsal root ganglion (DRG), respectively. Distinctly different roles of c-Jun activation have been suggested for these two types of neurons. In dissociated sympathetic neurons, c-Jun has been demonstrated to promote apoptosis, whereas in sensory neurons

Prey vulnerability to a gape-size limited predator: behavioural and morphological impacts on northern pike piscivory

The northern pike (Esox lucius) is a selective and important predator in lake ecosystems. Prey size in pike is limited by pike gape size, which is a linear function of pike body length. Here we show that the absolute gape-size limit in pike is greater than previously considered, and that maximum ingestible prey size is limited by prey body depth. Further, we experimentally show that pike prefer sh

Plasma Homocysteine Is Elevated in Elderly Patients with Memory Complaints and Vascular Disease.

Background: There is an association between elevated plasma total homocysteine (tHcy) and vascular disease in elderly patients suffering from organic and non-organic mental disease. The main objective of the present study was to investigate the relationship between plasma tHcy concentration and vascular disease in elderly patients with memory complaints. Methods: In 108 patients with memory compla

Development of the mesencephalic dopaminergic neuron system is compromised in the absence of neurogenin 2.

Neurogenin 2 (Ngn2) is a proneural gene involved in neuronal differentiation and subtype specification in various regions of the nervous system. In the ventral midbrain, Ngn2 is expressed in a spatiotemporal pattern that correlates with the generation of mesencephalic dopaminergic (mesDA) neurons. We show here that lack of Ngn2 impairs the development of mesDA neurons, such that less than half of

Modes of adherence of Helicobacter pylori to gastric surface epithelium in gastroduodenal disease: A possible sequence of events leading to internalisation

We have investigated various modes of adherence of Helicobacter pylori to the human gastric epithelium, using transmission electron microscopy, in biopsies from nine patients with peptic ulcer disease and from four patients with chronic active gastritis. H. pylori was demonstrated in abundance in all cases within the surface mucous layer. In all ulcer- and in one out of four gastritis patients H.

Surface Deposition and Phase Behavior of Oppositely Charged Polyion/Surfactant Ion Complexes. 1. Cationic Guar versus Cationic Hydroxyethylcellulose in Mixtures with Anionic Surfactants

Mixtures of cationic guar (cat-guar) or cationic hydroxyethylcellulose (cat-HEC) with the anionic surfactants sodium dodecyl sulfate or sodium lauryl ether-3 sulfate have been investigated by a wide range of complementary techniques (phase studies, turbidity measurements, dynamic light scattering, gel-swelling experiments, and in situ null ellipsometry), with the following objectives in mind: (1)

Sequential GC/MS analysis of sialic acids, monosaccharides, and amino acids of glycoproteins on a single sample as heptafluorobutyrate derivatives

A GUMS procedure was developed for the analysis of all major constituents of glycoproteins. The rationale for this approach is that by using GC/MS analysis of the constituents as heptafluorobutyrate derivatives, it was possible to quantitatively determine the sialic acid, monosaccharide, fatty acids (when present), and the amino acid composition with the sample remaining in the same reaction vesse