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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

XUV digital in-line holography using high-order harmonics

Abstract in Undetermined A step towards a successful implementation of time-resolved digital in-line holography with extreme ultraviolet (XUV) radiation is presented. Ultra-short XUV pulses are produced as high-order harmonics of a femtosecond laser and a Schwarzschild objective is used to focus harmonic radiation at 38 nm and to produce a strongly divergent reference beam for holographic recordin

Impact of microbial-feeding animals on total soil activity and nitrogen dynamics - a soil microcosm experiment

Abstract in UndeterminedThe long-term impact of microbial-feeding animals on microbial populations was studied in microcosms containing pine seedlings growing in a gamma sterilized humus-sand mixture. Organism communities of diverse complexity were introduced into the microcosms. The two main experimental series contained microorganisms only and microorganisms and microorganism-feeding nematodes,

Gelatinization of cassava, potato and wheat starches in supercritical carbon dioxide

The gelatinization of cassava, potato and wheat starches in supercritical carbon dioxide was investigated using light microscope. The starch was placed in a stainless steel chamber at atmospheric pressure and high CO2 pressures, 8 and 30 MPa as well as at 8 MPa N-2 and the gelatinization degree observed by light microscopy. The results showed that both pressure and supercritical fluid affected the

Epidemiology of childhood injuries in Reykjavik 1974-1991

OBJECTIVE: To determine and analyse the incidence of childhood injuries in Reykjavik 1974-1991. DESIGN: Descriptive, retrospective study. SETTING: Reykjavik City district with a mean number of 88700 inhabitants, of which 23.4% were children under 15 years of age. SUBJECTS: All children 0-14 years old who came to the emergency department at Reykjavik City Hospital because of an injury. MAIN OUTCOME

A digitally controlled PLL for digital SOCs

A fully integrated digitally controlled PLL used as a clock multiplying circuit is designed and fabricated. The PLL has no off-chip components and it is made from standard cells found in most digital standard cell libraries. It is therefore portable between processes as an IP-block. Using a 0.35 μm standard CMOS process and a 3.0 V supply, the PLL has a frequency range of 152 MHz to 366 MHz and oc

Diastolic blood pressure and area of residence: multilevel versus ecological analysis of social inequity

STUDY OBJECTIVES---To study geographical differences in diastolic blood pressure and the influence of the social environment (census percentage of people with low educational achievement) on individual diastolic blood pressure level, after controlling for individual age and educational achievement. To compare the results of multilevel and ecological analyses. DESIGN---Cross sectional analysis perf

Defect-free InP nanowires grown in [001] direction on InP(001)

We report on [001] InP nanowires grown by metalorganic vapor phase epitaxy directly on (001) InP substrates. Characterization by scanning electron microscopy and transmission electron microscopy reveals wires with nearly square cross sections and a perfect zinc-blende crystalline structure that is free of stacking faults. Photoluminescence measurements of single [001] nanowires exhibit a narrow an

Novel room-temperature functional analogue and digital nanoelectronic circuits based on three-terminal ballistic junctions and planar quantum-wire transistors

Three-Terminal ballistic junctions (TBJs) and planar quantum-wire transistors (QWTs) are emerging nanoelectronic devices with various novel electrical properties. In this work, we realize novel nanoelectronic analogue and digital circuits with TBJs and planar QWTs made on In0.75Ga0.25As/InP two-dimensional electron gas (2DEG) material. First we show that a single TBJ can work as a frequency mixer

CXCL16/SR-PSOX is an interferon-gamma-regulated chemokine and scavenger receptor expressed in atherosclerotic lesions

OBJECTIVE: Atherosclerosis is an inflammatory disease. Several chemokines are important for monocyte/macrophage and T-cell recruitment to the lesion. CXCL16 is a recently discovered chemokine that is expressed in soluble and transmembrane forms, ligates CXCR6 chemokine receptor, and guides migration of activated Th1 and Tc1 cells. It is identical to scavenger receptor SR-PSOX, which mediates uptak

Ultrafiltration of colloidal dispersions - A theoretical model of the concentration polarization phenomena

A general thermodynamic model of the concentration polarization phenomena of colloidal particles at a membrane surface is presented. The model is based on the balance between a thermodynamic force, due to the osmotic pressure gradient, and a frictional force, due to the fluid flow around each particle. A cell model description is used to model the concentration dependence of the thermodynamic forc

The neuropeptides vasoactive intestinal polypeptide, peptide histidine isoleucine and neuropeptide Y modulate [3H]noradrenaline release from sympathetic nerves in the choroid plexus

The neurotransmitter peptides vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine (PHI) and neuropeptide Y (NPY) are located in nerve fibers supplying the pig choroid plexus, which receives an abundant sympathetic innervation. We characterized the release of [3H]noradrenaline ([3H]NA) from this tissue elicited by electrical field stimulation and studied the effects of the above-m