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This study investigates the size and power properties of three multivariate tests for autocorrelation, namely portmanteau test, Lagrange multiplier (LM) test and Rao F-test, in the stable and unstable vector autoregressive (VAR) models, with and without autoregressive conditional heteroscedasticity (ARCH) using Monte Carlo experiments. Many combinations of parameters are used in the simulations to

The time-dependent traveling salesman problem (TDTSP) is a variant of TSP with time-dependent edge costs. We study some restrictions of TDTSP where the number of edge cost changes are limited. We find competitive ratios for online versions of TDTSP. From these we derive polynomial time approximation algorithms for graphs with edge costs one and two. In addition, we present an approximation algorit

We investigate the light emission from dipolar emitters located within nanoparticle antennas. It is found that the enormous emission enhancement can reach nearly a million fold. For multinanoparticle antennas, the polarization of the emissions strongly depends on the geometry of the antennas, the emitted wavelengths, and the dielectric functions of surrounding media. It is shown that a polarizatio

Molecular imprinting is a versatile technique providing functional materials able to recognize and in some cases respond to biological and chemical agents of interest. In contrast to biological antibodies, the best known receptors derived from biological combinatorial processes, molecularly imprinted polymers (MIPs) are obtained by template-directed synthesis. Thus, molecular imprinting can more p

Prevention of incorporation of dUTP into DNA is essential for maintenance of the genetic information. Prompt and specific removal of dUTP from the nucleotide pool, as expedited by the ubiquitous enzyme dUTPase, is therefore required for full viability in most biological systems. Conserved structural features perpetuate specificity in choice of substrate, which is crucial as hydrolysis of the struc

Background: Electrocardiogram-derived grades of ischemia at the time of patient presentation with acute myocardial infarction have proved useful in predicting the salvageability by reperfusion therapy, final infarct size, severity of left ventricular dysfunction, and short- and long-term prognosis. Subjects and Methods: The Sclarovsky-Birnbaum Ischemia Grading System based on the relation between

Screen-printing technology for electrode fabrication enables construction of amperometric devices suitable for combination of several enzyme electrodes. To develop a biosensor array for characterisation of wastewaters, tyrosinase and horseradish peroxidase (HRP) or cholinesterase-modified electrodes were combined on the same array. The behaviour of the tyrosinase-modified electrode in the presence

A mathematical model for the hindered diffusion and competitive adsorption of two proteins in an agarose gel has been developed. In a simulation program the model has been used to study the competing and displacement effects on a single bead for lysozyme and bovine serum albumin (BSA) bound to the ligand Cibacron Blue in agarose gel. The model takes into account hindered diffusion described by the

The present communication considers possibilities of how to improve surveillance programs for sexually transmitted infections and some conditions not yet included among the 'established' sexually transmitted infections. An extended list of sexually transmitted infection agents is proposed for monitoring and a syndrome-based surveillance program for what and when to screen pregnant women is discuss

This paper provides an overview of the state-of- the-art radio propagation and channel models for wireless multiple-input multiple-output (MIMO) systems. We distinguish between physical models and analytical models and discuss popular examples from both model types. Physical models focus on the double-directional propagation mechanisms between the location of transmitter and receiver without takin

In the era of proteomics, glycomics and ultimately metabolomics, with constantly increasing knowledge regarding the human biosystem, the number of specialized therapeutic agents which will be developed against different diseases is predicted to be on the upswing. An increasing portion of these new drugs will, according to recent predictions (Labrou, 2003), be of proteinaceous origin produced accor

Popular Abstract in Swedish Katalys är en nyckelteknik inom kemisk industri och spelar en förvånansvärt viktig roll i vårt moderna samhälle. Många av de produkter och kemikalier som används i vårt dagliga liv produceras faktiskt med hjälp av katalysatorer. En annan mycket viktig tillämpning är att avlägsna giftiga ämnen från fordonsavgaser. Det mest fantastiska är att en katalysator snabbar på ochThis PhD thesis reports on investigations of the atomic scale structure of model catalysts relevant for the catalytic oxidation of CO and methane over Pd, and NOx reduction over silver-alumina, important reactions in automotive catalysts. By using complementary experimental techniques such as X-ray Photoelectron Spectroscopy, High Pressure X-ray Photoelectron Spectroscopy, Surface X-ray Diffractio

In communication systems, all service control nodes, such as for example Web sites or mobile switching centers, can be modeled as a server system with one or more servers processing the incoming requests. To avoid overload at the service node some type of admission control mechanism is usually implemented to guarantee good performance also during high traffic loads. In this paper we investigate, f

The electrical output of low concentration systems with standard pv cells is heavily impaired by non uniform irradiation distribution on the cells. In order to design new concentrators that improve the system efficiency by homogenizing the light, a new method of evaluation has been developed. It is based on simulations, and generates an estimated annual output. The method consists of three steps,

Popular Abstract in Swedish Vibrationsskador i händerna utgör idag ett stort yrkesmedicinskt problem. Långvarig exponering av handhållna vibrerande verktyg kan leda till ett hand-arm vibrationssyndrom (HAVS) som är en kronisk åkomma. Vibrationsskadan kan vara irreversibel och är progressiv om vibrationsexponeringen fortsätter. Många arbetare utsätts dagligen för hand-arm vibrationer. Elva procent Workers exposed to hand-held vibrating machines may risk developing a hand-arm vibration syndrome (HAVS), a condition which can cause chronic impairment and disability. The aims of this thesis were 1) to obtain deeper insight and further knowledge of HAVS and the consequences for hand function, and aspects of quality of life (QoL); 2) to investigate the usefulness of clinical assessments in diagno