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Comparison of the chemical properties of iron and cobalt porphyrins and corrins.

Density functional calculations have been used to compare various geometric, electronic and functional properties of iron and cobalt porphyrin (Por) and corrin (Cor) species. The investigation is focussed on octahedral MII/III complexes (where M is the metal) with two axial imidazole ligands (as a model of b and c type cytochromes) or with one imidazole and one methyl ligand (as a model of methylc

The diffusion of water vapour through pulp and paper

The diffusion of water vapour through pulp and paper was investigated experimentally in a diffusion cell. The diffusion cell consisted of two chambers differing in relative humidity. Any given sample was placed as a barrier between the two chambers. Two pulp qualities and eleven paper grades were included in the investigation. The diffusivities measured ranged from 2.1-10(-8) m2/s to 5.4.10(-6) m2

Molecularly imprinted polymers in capillary electrochromatography: Recent developments and future trends.

The developments in molecularly imprinted polymer (MIP)-based capillary electrochromatography (CEC) achieved during the past years are reviewed in this article. The MIP is prepared using a templated polymerization reaction and results in a material with a high selectivity towards a predetermined target. The selectivity of the MIP is comparable to that of the biological antibodies, however, the MIP

Thin layers of GaInP, GaP and GaAsP in metalorganic vapour phase epitaxy-grown resonant tunnelling diodes

We have studied the epitaxial growth and electrical performance of Al-free, GaAs-based, resonant tunnelling diodes (RTDs) including thin barriers of GaInP, GO, or GaAsxP1-x. n-Type tunnelling diodes have been fabricated and the symmetry in the current-voltage (I-V) characteristics, as well as the peak-to-valley ratios, are found to be sensitive probes for the inter-face quality in the heterostruct

Diagnosis of acute promyelocytic leukaemia by RT-PCR: detection of PML-RARA and RARA-PML fusion transcripts

Acute promyelocytic leukaemia (APL; AML M3) is identified by a unique t(15;17) translocation which fuses the PML gene to the retinoic acid receptor alpha gene (RARA). Reverse transcription coupled with the polymerase chain reaction (RT-PCR) has been used to develop a diagnostic test for APL based on the PML-RARA fusion message. Separate PCR assays were designed to amplify either PML-RARA (15q+ der

Regional assessment of the temporal trends in soil acidification in Southern Sweden, using the safe model

The dynamic soil acidification model SAFE was applied to 44 forested sites in Skåne, southern Sweden, using available Swedish databases on present soil status, vegetation and deposition. Time series of deposition were derived for each site from present deposition in a generalized fashion by dividing deposition into different classes and scaling with deposition trends from the literature. This stud

Electronic Doppler effect in resonant Auger decay of CO molecules upon excitation near a shake-up Pi resonance

We present an experimental observation of the electronic Doppler effect in resonant Auger spectra upon core excitation slightly above the carbon K edge of the CO molecule. Thus the electronic Doppler effect has been identified in above-threshold excitation, and in a transition of Pi symmetry. Ab initio calculations of the potential energy curves of the relevant states of CO and the wave packet tec

Primer: history and examination in the assessment of musculoskeletal problems

Musculoskeletal problems are very common, and clinical assessment is central to their appropriate management; however, many clinicians are not sufficiently competent to carry out this assessment. A standardized approach to the clinical assessment of a musculoskeletal problem is, therefore, necessary, whether the patient is presenting to primary care, rheumatology or orthopedics. Such a standardize

The influence of predator regime on reproductive traits in Gammarus pulex populations

Selection on traits conferring reduced predation may be opposed by selection on other traits associated with reproduction. Here, we examined the hypothesis that traits associated with reproduction in Gammarus pulex are driven by predation. We studied G. pulex originating from ponds with two different kinds of predator regimes: (1) ponds with fish-often large, non-gap-limited predators and (2) pond

Application of antisense transformation of a barley chitinase in studies of arbuscule formation by a mycorrhizal fungus

Barley (Hordeum vulgare L.) plants of two commercial cultivars were transformed with sense and antisense constructs of a chitinase class II gene in order to develop a transformation system for this gene in barley. Transformation of embryos with the two antisense constructs resulted in ten regenerated plants, while no plants could be obtained using the sense construct. The presence of the inserted

Tumor necrosis factor (TNF)-mediated activation of the p55 TNF receptor negatively regulates maintenance of cycling reconstituting human hematopoietic stem cells

Hematopoietic stem cell (HSC) fate decisions between self-renewal and commitment toward differentiation are tightly regulated in vivo. Recent developments in HSC culture and improvements of human HSC assays have facilitated studies of these processes in vitro. Through such studies stimulatory cytokines critically involved in HSC maintenance in vivo have been demonstrated to also promote HSC self-r

Some attacks on the Bit-search generator

The bit-search generator (BSG) was proposed in 2004 and can be seen as a variant of the shrinking and self-shrinking generators. It has the advantage that it works at rate 1/3 using only one LFSR and some selection logic. We present various attacks on the BSG based on the fact that the output sequence can be uniquely defined by the differential of the input sequence. By knowing only a small part o

The MSX1 homeobox transcription factor is a downstream target of PHOX2B and activates the Delta-Notch pathway in neuroblastoma

Neuroblastoma is an embryonal tumour of the peripheral sympathetic nervous system (SNS). One of the master regulator genes for peripheral SNS differentiation, the homeobox transcription factor PHOX2B, is mutated in familiar and sporadic neuroblastomas. Here we report that inducible expression of PHOX2B in the neuroblastoma cell line SJNB-8 down-regulates MSX1, a homeobox gene important for embryon

The menopause revisited

The continuing growth of female life expectancy has resulted in a marked increase of women in years beyond the menopause. Women can nowadays expect to live one-third of their lives in a potential hormonal deficiency state. Women over 50 comprise 17% of the total population of any country in the modern western world. Any decision regarding their health issues will have a great impact on our limited

Energy Simulations for Glazed Office Buildings in Sweden

Highly glazed buildings are designed by architects to be airy, light and transparent with more access to daylight. Their energy efficiency, however, has become questioned. Therefore, energy simulations of single skin office buildings in Sweden were carried out, using a dynamic energy simulation tool. In order to study the impact of glass on the energy use during the occupation stage, office buildi

Association of HLA-DQ5 and HLA-DR1 with sensitization to organic acidanhydrides

Background Organic acid anhydrides are low molecular weight industrial chemicals, able to cause rhinoconjunctivitis and asthma associated with specific IgE against hapten-carrier protein conjugate. Only a proportion of exposed workers develop IgE-associated allergy to acid anhydrides. Objective We determined whether genetic susceptibility, in particular, HLA Class II alleles may be a risk factor.

A new strychnos alkaloid from Strychnos scheffleri

A phytochemical investigation of the stem bark of Strychnos scheffleri resulted in the isolation of a new strychnos alkaloid N-a-deacetylmalagashine (1) together with the known derivative malagashine (2). Elucidation of the structures was based mainly on ID and 2D NMR and MS studies and by comparison with related compounds.