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Constrained Mechanical Systems in Descriptor form: Identification, Simulation and Control

The subject of constrained controlled mechanical (“mechatronic”) systems in descriptor form is a field of current research in mechanical engineering, control theory and applied mathematics. It is essentially based on the progress in numerical mathematics on the solution of differential-algebraic equations, cf. [1–3] and on the developments in control theory on singular (or descriptor) systems, cf.

The foldable "Ottenby" walk-in trap: a handy and efficient wader trap for expedition conditions.

We describe the history, construction, and use of a portable walk-in wader trap (i.e., modified Ottenby trap) designed to be used in field expedition conditions. It is rectangular-shaped, 120 x 41 x 32 cm when operational, weighs between 1.5 and 2 kg (depending on materials used) and can be folded flat for easy transportation. It consists of several metal frames filled with fishing net, and has a

Platination of the siRNA sense-strand modulates both efficacy and selectivity in vitro

The use of short interfering RNAs (siRNA) for selective suppression of protein production has rapidly become a commonly used technique for transient modulation of protein levels. In the present paper, we investigate whether introduction of platinated bases in the sense strand can be used to modulate the efficacy of siRNAs. Four different siRNAs were studied, all targeting the initial AU-rich 3' UT

Detection and prevention of hepatitis C in dialysis patients and renal transplant recipients. A long-term follow up (1989-january 1997)

Background. Hepatitis C is frequent problem in dialysis wards. Design. A long time (1989-97) follow up of hepatitis C virus (HCV) infection in a Swedish nephrology unit was performed with anti-HCV screening, confirmatory antibody tests, viral RNA detection and molecular characterization. Case histories were reviewed with focus, onset of infection, liver morbidity and mortality. Results. In October

Relationship of airway responsiveness to agents causing bronchoconstriction and cough in sensitized guinea-pigs

The relationship between airway responsiveness to bronchoconstrictor- and cough-inducing stimuli has been examined in Ascaris suum-sensitized conscious guinea-pigs. Guinea-pigs were sensitized to Ascaris suum [4000 PNU and 100 mg Al(OH)3 i.p. on days 1 and 7] and then challenged with aerosolized antigen on days 21, 28 and 35. At day 35, antigen-exposure produced an early bronchoconstrictor respons

Deletion of a lectin gene does not affect the phenotype of the nematode-trapping fungus Arthrobotrys oligospora

A number of filamentous fungi are known to produce high levels of saline-soluble and low-molecular-mass lectins. The function of these proteins are not clear but it has been proposed that they are involved in storage of nutrients, development, recognition of other organisms, and defense reactions. A gene encoding such a lectin (AOL) was deleted in the nematode-trapping fungus Arthrobotrys oligospo

Safe Reference Following on the Inverted Pendulum

This work discusses methods to obtain reference following on unstable systems. The task is critical; introduction of refernce signal might cause instability in some cases. It is thus interesting to develop strategies that offer acceptable reference following, but also guarantees stability. In practice similiar problems arises in flight control systems for unstable fighter aircrafts. Experimental v

Packaging demands in the food service industry

The European food service market was estimated, in 1999, to be worth US$293 billion with high profit margins and a growth rate of 2.75%. Future demand for value-added products and high levels of customization will stress the issue of keeping profit margins in the food service industry. Packaging is a critical issue, because it adheres to the product throughout the entire food service supply chain.

Comparison of atrial signal extraction algorithms in 12-lead ECGs with atrial fibrillation

Analysis of atrial rhythm is important in the treatment and management of patients with atrial fibrillation. Several algorithms exist for extracting the atrial signal from the electrocardiogram (ECG) in atrial fibrillation, but there are few reports on how well these techniques are able to recover the atrial signal. We assessed and compared three algorithms for extracting the atria] signal from th