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Unitary partitioning in general constraint preserving DAE integrators

A number of numerical algorithms have been developed for various special classes of DAEs. This paper describes a new variable step size, constraint preserving integrator for general non-linear fully implicit higher index DAEs. Numerical implementation issues are discussed. Numerical examples illustrate the effectiveness of the new method.

Synthesis and characterization of molybdenum oxo complexes of two tripodal ligands: reactivity studies of a functional model for molybdenum oxotransferases

Reaction of the tetradentate ligand N-(2-hydroxybenzyl)-N, N-bis(2-pyridylmethyl) amine (L - OH) with MoO2Cl2 in methanol in the presence of NaOMe and PF6- results in the formation of [MoO2(L - O)] PF6. Similarly, the reaction of N-(2-mercaptobenzyl)- N,N-bis(2-pyridylmethyl) amine (L -SH) with MoO2(acac)(2) leads to the formation of [MoO2(L - S)](+). The dioxo-molybdenum complex [MoO2(L - O)](+)

Preservation of a functional nigrostriatal dopamine pathway by GDNF in the intrastriatal 6-OHDA lesion model depends on the site of administration of the trophic factor

Here we studied whether glial cell line-derived neurotrophic factor (GDNF), given as a single bolus injection before an intrastriatal 6-hydroxydopamine (6-OHDA) lesion, can protect the nigrostriatal dopamine neurons against the toxin-induced damage and preserve normal motor functions in the lesioned animals. GDNF or vehicle was injected in the striatum (25 microg), substantia nigra (25 microg) or

Long-term trends of inorganic chlorine from ground-based infrared solar spectra: Past increases and evidence for stabilization

Long-term time series of hydrogen chloride (HCl) and chlorine nitrate (ClONO2) total column abundances has been retrieved from high spectral resolution ground-based solar absorption spectra recorded with infrared Fourier transform spectrometers at nine NDSC (Network for the Detection of Stratospheric Change) sites in both Northern and Southern Hemispheres. The data sets span up to 24 years and mos

Classification of fungi by means of pyrolysis-gas chromatography pattern recognition

SUMMARY Repetitive samples of three strains of the moujd Penicillium were subjected to pyrolysis-gas chromatography (Py-GC). From the chromatograms, 26 peak heights were used in a subsequent SIMCA pattern recognition analysis. This data analysis gives a marked improvement in the classification of the samples (100% correct, 85% unique) in comparison with the traditional analysis based on the averag

Prolonging the system lifetime and equalising the energy for heterogeneous sensor networks using RETT protocol

In some Wireless Sensor Network (WSN) deployments, nodes may be used for different purposes (sensing, data pre-processing, actuation, etc.). Even if such a network is organised into clusters, this creates heterogeneity in terms of energy capability, which needs to be managed and balanced in order to ensure proper sensing capability with maximised lifespan. In this paper, we present Routing based o

RETT-gen: A globally efficient routing protocol for wireless sensor networks by equalising sensor energy and avoiding energy holes

Wireless sensor networks are composed of a large number of sensor nodes with limited energy resources. Once deployed, the sensor nodes are usually inaccessible to the user, and thus replacement of the energy resource is not feasible. Hence, energy efficiency is a key design issue that needs to be enhanced in order to improve the life span of the entire network. Several routing protocols have been

Distribution of PG-M/versican variants in human tissues and de novo expression of isoform V3 upon endothelial cell activation, migration, and neoangiogenesis in vitro

We have carried out a comprehensive molecular mapping of PG-M/versican isoforms V0-V3 in adult human tissues and have specifically investigated how the expression of these isoforms is regulated in endothelial cells in vitro. A survey of 21 representative tissues highlighted a prevalence of V1 mRNA, demonstrated that the relative frequency of expression was V1>V2>V3greater than or equal toV2; and s

Visual navigation in desert ants Cataglyphis fortis: are snapshots coupled to a celestial system of reference?

Central-place foraging insects such as desert ants of the genus Cataglyphis use both path integration and landmarks to navigate during foraging excursions. The use of landmark information and a celestial system of reference for nest location was investigated by training desert ants returning from an artificial feeder to find the nest at one of four alternative positions located asymmetrically insi

Collisions and close encounters involving massive main-sequence stars

We study close encounters involving massive main-sequence stars and the evolution of the exotic products of these encounters as common-envelope systems or possible hypernova progenitors. We show that parabolic encounters between low- and high-mass stars and between two high-mass stars with small periastrons result in mergers on time-scales of a few tens of stellar free-fall times (a few tens of ho

Non-genomic effects of androgens on isolated human vascular and nonvascular penile erectile tissue

OBJECTIVES To evaluate non-genomic effects of testosterone and dihydrotestosterone (DHT) on isolated human cavernosal arteries (HCA) and corpus cavernosum (HCC) using organ-bath studies and radio-immunoassays (RIA), as non-genomic effects of androgens are reported for vascular smooth musculature and there is evidence that the relaxant response involves a modulation of cyclic nucleotide tissue leve

Low-dose GH improves exercise capacity in adults with GH deficiency: effects of a 22-month placebo-controlled, crossover trial

Fifty-five patients with adult-onset GH deficiency (mean age, 49 years) were enrolled in a placebo-controlled, crossover study to investigate the effects of GH therapy on exercise capacity, body composition, and quality of life QOL). GH and placebo were administered for 9 months each, separated, by a 4-month washout period. GH therapy was individually dosed to obtain an IGF-I concentration within

Granule targeting of soluble tumor necrosis factor (TNF) receptor expressed during granulopoietic maturation in murine bone marrow cells.

In this experiment, we explored the potential of secretory lysosomes of hematopoietic cells to act as vehicles for immunomodulatory protein delivery at an inflammation site. We investigated whether exogenous soluble TNF-receptor 1 (sTNFR1) could be expressed in primary hematopoietic progenitor cells and become targeted for storage and secretion during granulopoietic differentiation. An sTNFR1 cons

Study of flame stabilization in a swirling combustor using a new flamelet formulation

The dynamics in a swirl-stabilized flame is studied using large eddy simulation (LES). We account for the effect of turbulence on the flame through a model based on a filtered flamelet technique. The model provides a consistent and robust reaction-diffusion expression for simulating the correct propagation of premixed flames. The filtered flamelet formulation has been implemented into a high-order

Elastic properties of the lung and the chest wall in young and adult healthy pigs

Understanding of the elastic pressure/volume (Pel/V) curve is still limited in health and disease. The aim of the present study was to elucidate the Pel/V curve and elastance of the respiratory system (ERS) lung (EL) and chest wall (ECW) in healthy pigs. Six young (20.8 kg) and seven adult (58.9 kg), anaesthetized, paralysed and ventilated pigs were studied. Pel/V curves were recorded at zero end-

Less small-bowel injury with lumiracoxib compared with naproxen plus omeprazole

Background & Aims: The selective cyclooxygenase-2 inhibitor lumiracoxib has been shown to reduce endoscopically detected ulcers and ulcer complications in the upper gastrointestinal tract compared with nonselective nonsteroidal anti-inflammatory drugs. We investigated whether lumiracoxib would reduce small-bowel injury compared with naproxen plus omeprazole. Methods: Healthy volunteers were ra