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Elliptically polarised soft X-rays produced using a local bump in MAX II characterisation of the degree of polarisation

MAX-lab has introduced a local perturbation to the electron orbit of the MAX II storage ring, providing users at the SX700 monochromator beam line, D1011, with elliptically polarised soft X-rays. This is achieved by using corrector magnets to send the electron orbit on an ascending or descending trajectory through the dipole magnet source. This simple "bump" approach has many advantages over and a

Ion-Ion Correlation and Charge Reversal at Titrating Solid Interfaces

Confronting grand canonical titration Monte Carlo simulations (MC) with recently published titration and charge reversal (CR) experiments on silica surfaces by Dove and Craven (Dove, P. M.; Craven, C. M. Geochim. Cosmochim. Acta 2005, 69, 4963-4970) and van der Heyden et al. (van der Heyden, F. H. J.; Stein, D.; Besteman, K.; Lemay, S. G.; Dekker, C. Phys. Rev. Lett. 2006, 96, 224502), we show tha

Characteristics of cardiac arrest and resuscitation by age group: an analysis from the Swedish Cardiac Arrest Registry

Aim: The objective of this study was to describe patients who experienced an out-of-hospital cardiac arrest (OHCA) by age group. Methods: All patients who suffered from an OHCA between 1990 and 2005 and are included in the Swedish Cardiac Arrest Registry (n = 40,503) were classified into the following age groups: neonates, younger than 1 year; young children, between 1 and 4 years; older children,

Density estimation for the Metropolis-Hastings algorithm

Kernel density estimation is an important tool in visualizing posterior densities from Markov chain Monte Carlo output. It is well known that when smooth transition densities exist, the asymptotic properties of the estimator agree with those for independent data. In this paper, we show that because of the rejection step of the Metropolis-Hastings algorithm, this is no longer true and the asymptoti

Surface complexation of DNA with insoluble monolayers. Influence of divalent counterions

DNA interacts with insoluble monolayers made of cationic amphiphiles as well as with monolayers of zwitterionic lipids in the presence of divalent ions. Binding to dioctadecyldimethylammonium bromide (DODAB) or distearoyl-sn-glycero-3-phosphocholine (DSPC) monolayers in the presence of calcium is accompanied by monolayer expansion. For the positively charged DODAB monolayer, this causes a decrease

Early Holocene terrestrial climatic variability along a North Atlantic Island transect: palaeoceanographic implications

A synthesis of the early Holocene climatic development in the North Atlantic region is presented, based on three previously published lake records from southern Greenland (Lake N14), Iceland (Lake Torfadalsvatn) and the Faroe Islands (Lake Lykkjuvotn). The interval 11500-8500 cal BP has been divided into five phases with respect to the inferred strength of the North Atlantic Current (NAC) and Irmi

Characterization of behavioral and neurodegenerative changes following partial lesions of the nigrostriatal dopamine system induced by intrastriatal 6-hydroxydopamine in the rat

Partial lesions of the nigrostriatal dopamine system have been investigated with respect to their ability to induce consistent long-lasting deficits in movement initiation and skilled forelimb use. In eight different lesion groups 6-hydroxydopamine (6-OHDA) was injected at one, two, three, or four sites into the lateral sector of the right striatum, in a total dose of 20-30 microgram. Impairments

Thermostable carbohydrate-binding modules in affinity chromatography

Affinity chromatography is routinely used mostly on a preparative scale to isolate different biomolecules such as proteins and carbohydrates. To this end a variety of proteins is in common use as ligands. To extend the arsenal of binders intended for separation of carbohydrates, we have explored the use of carbohydratebinding modules (CBM) in affinity chromatography. The thermostable protein CBM4-

Hidden Markov model-based packet loss concealment for voice over IP

As voice over IP proliferates, packet loss concealment (PLC) at the receiver has emerged as an important factor in determining voice quality of service. Through the use of heuristic variations of signal and parameter repetition and overlap-add interpolation to handle packet loss, conventional PLC systems largely ignore the dynamics of the statistical evolution of the speech signal, possibly leadin

Decision Support for the Initial Triage of Patients with Acute Myocardial Infarction

Objectives: To develop an automated tool for the analysis of electrocardiograms (ECG) with respect to changes that make the patient a candidate for reperfusion therapy. An additional aim was to assess the influence of the tool on the ECG classifications of three interns. Methods and Results: An artificial neural network was trained to interpret ECGs regarding changes making the patient a candi

The meaning of psychosocial occupational therapy in a life-story perspective. A long-term follow-up of three cases.

This study is a long-term follow-up in narrative form of three former psychiatric patients who had been discharged eight to nine years earlier from an outpatient occupational therapy programme. The purpose of the study was to gain an understanding about the participants' views about the period of therapy from a long-term perspective and of how the outcome of therapy could be understood within the

Long-term temporal trends in cardiovascular and metabolic risk factors

OBJECTIVES: Metabolic factors such as obesity, hypertension, dyslipidemia and hyperglycemia have consistently been associated with increased risk of cardiovascular disease. There is also growing evidence that these factors are linked to cancer incidence and mortality. The aim of this study was to investigate long-term trends in major metabolic risk factors in three large cohorts. MATERIALS AND MET

Experimental evidence for sub-3-fs charge transfer from an aromatic adsorbate to a semiconductor

The ultrafast timescale of electron transfer processes is crucial to their role in many biological systems and technological devices. In dye-sensitized solar cells(1-4), the electron transfer from photoexcited dye molecules to nanostructured semiconductor substrates needs to be sufficiently fast to compete effectively against loss processes and thus achieve high solar energy conversion efficiencie

Shikimic acid production by a modified strain of E-coli (W3110.shik1) under phosphate-limited and carbon-limited conditions

Shikimic acid is one of several industrially interesting chiral starting materials formed in the aromatic amino acid pathway of plants and microorganisms. In this study, the physiology of a shikimic acid producing strain of Escherichia coli (derived from W31 10) deleted in aroL (shikimic acid kinase II gene), was compared to that of a corresponding control strain W31 10) under carbonand phosphate-

Colloid Adsorption onto Responsive Membranes.

The adsorption of colloids with varying sizes and charges onto a surface carrying both negative and positive charges representing a membrane has been investigated by using a simple model employing Monte Carlo simulations. The membrane is made of positive and negative charges (headgroups) that are allowed to move along the membrane, simulating the translational diffusion of the lipids, and are also