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Preparation of molecularly imprinted polymers in supercritical carbon dioxide

Molecularly imprinted polymer nanoparticles were prepared in supercritical carbon dioxide using a noncovalent imprinting approach. In the present work, propranolol was used as a model template, methacrylic acid as a functional monomer, and divinylbenzene as a crosslinker. Under a high dilution condition, the heterogeneous polymerization resulted in discrete crosslinked polymer nanoparticles. Compa

Spectral Data for Ta II with Application to the Tantalum Abundance in chi Lupi

Tantalum spectra, emitted from a hollow cathode, have been recorded with a Fourier transform spectrometer in the region 2000–5000 Ů The observed hyperfine patterns of Ta II have been analyzed, yielding center-of-gravity wavelengths for 199 lines and hyperfine constants for 38 even and 97 odd levels of Ta II. Improved energy level values have been derived. The laboratory data have been used for a s

Monte Carlo based verification of a beam model used in a treatment planning system

Modern treatment planning systems (TPSs) usually separate the dose modelling into a beam modelling phase, describing the beam exiting the accelerator, followed by a subsequent dose calculation in the patient. The aim of this work is to use the Monte Carlo code system EGSnrc to study the modelling of head scatter as well as the transmission through multi-leaf collimator (MLC) and diaphragms in the

Large particles are responsible for elevated bacterial marker levels in school air upon occupation

Muramic acid (Mur) is found in bacterial peptidoglycan ( PG) whereas 3-hydroxy fatty acids (3-OH FAs) are found in Gram-negative bacterial lipopolysaccharide (LPS). Thus Mur and 3-OH FAs serve as markers to assess bacterial levels in indoor air. An initial survey, in a school, demonstrated that the levels of dust, PG and LPS (pmol m(-3)) were each much higher in occupied rooms than in the same roo

MRI in acute transverse myelopathy

The MRI examinations of seven patients with acute transverse myelopathy (ATM) were analysed. The patients were examined 2-5 times during the course of their disease with short and long TR/TE spin-echo sequences in the sagittal projection. A previous history of autoimmune disorder and/or signs of infection at the onset of ATM were present in all cases. Cerebrospinal fluid analysis showed local synt

Using narrative analysis to understand the combined use of complementary therapies and bio-medically oriented health care

Rather than using different therapies in isolation, many cancer patients use different therapies in a complementary fashion. Little research to date has given attention to individuals' experiences of the combined use of biomedically oriented health care (BHC) and complementary and alternative therapies (CATs). Therefore, this paper examines one individual's negotiation between complementary self-c

Temporary cyst formation in phytoplankton: a response to allelopathic competitors?

Competition among phytoplankton for limiting resources may involve direct or indirect interactions. A direct interaction of competitors is the release of chemicals that inhibit other species, a process known as allelopathy. Here, we investigated the allelopathic effect of three toxic microalgae species (Alexandrium tamarense, Karenia mikimotoi and Chrysochromulina polylepis) on a natural populatio

Soil microbial activity in eleven Swedish coniferous forests in relation to site fertility and nitrogen fertilization

The effect of forest fertilization on soil microbial activity and biomass was studied in 11 coniferous forests with different site fertility. Soil microbial activity was measured as respiration rate and the microbial biomass was estimated using ATP content and substrate-induced respiration rate (SIR). At all sites, except those with the highest site fertility, the microbial activity and biomass we

Clonal derivation and characterization of human embryonic stem cell lines

Human embryonic stem cells (hESC) are isolated as clusters of cells from the inner cell mass of blastocysts and thus should formally be considered as heterogeneous cell populations. Homogenous hESC cultures can be obtained through subcloning. Here, we report the clonal derivation and characterization of two new hESC lines from the parental cell line SA002 and the previously clonally derived cell l

A Polar Cannabinoid from Cannabis sativa var. Carma

The aerial parts of Cannabis saliva var. Carma afforded a novel polar cannabinoid whose structure was established as rac-6',7'-dihydro,6',7'-dihydroxycannabigerol (carmagerol, 1) on the basis of spectroscopic data and semisynthesis from cannabigerol (2a). The dihydroxylation of the omega-double bond was detrimental to the anti-bacterial activity.

Forward jet production at HERA

Measurements in the low Bjorken-x region of deep inelastic electron-proton scattering events, containing a jet of high transverse momentum close to the flight direction of the proton, offer high sensitivity to BFKL-like dynamics. The results of recent measurements at HERA by the H1 and ZEUS experiments are presented.

Concurrent gain of 17q and the MYC oncogene in a medullomyoblastoma

Medullomyoblastoma (MMB) is a rare cerebellar childhood tumor containing both myoblastic and primitive neuroectodermal components. Similar to the scenario in classical medulloblastoma, which contains the primitive neuroectodermal component only, gain of sequences from the long arm of chromosome 17 (17q) and gain of the MYC gene in 8q have been implicated in the pathogenesis of MMB. Because karyoty

Long-term exposure of mouse pancreatic islets to oleate or palmitate results in reduced glucose-induced somatostatin and oversecretion of glucagon

Aims/hypothesis Long-term exposure to NEFAs leads to inhibition of glucose-induced insulin secretion. We tested whether the release of somatostatin and glucagon, the two other major islet hormones, is also affected. Methods Mouse pancreatic islets were cultured for 72 h at 4.5 or 15 mmol/l glucose with or without 0.5 mmol/l oleate or palmitate. The release of glucagon and somatostatin during subse

Synthesis of 2-pyridone-fused 2,2 '-bipyridine derivatives. An unexpectedly complex solid state structure of 3,6-dimethyl-9H-4,5,9-triazaphenanthren-10-one

2- Pyridone- fused 2,2'- bipyridine derivatives 1a and 1b were synthesised. X- Ray diffraction analysis of 1b revealed a highly complex solid state structure with a disordered molecule imbedded in a channel structure formed by a centrosymmetric lattice of hexagonally packed, hydrogen bonded columns. The columns are assembled from three symmetry independent molecules. Dimerisation of the self- comp

Metabolic activity of Glomus intraradices in Arum- and Paris-type arbuscular mycorrhizal colonization

Colonization of two plant species by Glomus intraradices was studied to investigate the two morphological types (Arum and Paris), their symbiotic interfaces and metabolic activities. Root pieces and sections were stained to observe the colonization and metabolic activity of all mycorrhizal structures. There were no growth responses observed in the plants caused by mycorrhizal symbiosis. The two mo

Cylinder air/fuel ratio estimation using net heat release data

An estimation model which uses the net heat release profile for estimating the cylinder air/fuel ratio of a spark ignition engine is developed. The net heat release profile is computed from the cylinder pressure trace and quantifies the conversion of chemical energy of the reactants in the charge into thermal energy. The net heat release profile does not take heat- or mass transfer into account. C

Team care. Traditions and new trends

lMajor changes have occurred in the care of patients with rheumatic diseases over the past decades. Most of these changes have focused on new pharmacological and surgical procedures and methods. However, for different reasons, few of these methods are available to many patients around the world, and thus other forms of care are still needed. For optimal benefit to patients, all aspects of care sho