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Metal chelate affinity precipitation: purification of (His)6-tagged lactate dehydrogenase using poly(vinylimidazole-co-N-isopropylacrylamide)copolymers

Affinity precipitation is a highly selective bioseparation method, which has been successfully used in the purification of various enzymes/proteins. The separation of (His)6-tagged lactate dehydrogenase ((His)6-LDH) was carried through affinity precipitation technique using thermoresponsive copolymer poly(vinylimidazole-co-N-isopropyl-acrylamide) (poly(VI-NIPAM)). Nearly quantitative recovery of (

High frequency characterization of a GaInAs/InP electronic waveguide T-branch switch

We report comprehensive microwave measurements on a T-branch switch; a GaInAs/InP electron waveguide based structure. The study includes a small signal model of the device where limitations of high frequency operation are discussed. An example of large signal operation where the nonlinearity of the device is exploited by operating the T-branch switch as a frequency multiplier is demonstrated.

Theoretical and experimental evaluation of phase-dispersion effects caused by brain motion in diffusion and perfusion MR imaging

We investigated intravoxel phase dispersion caused by pulsatile brain motion in diffusion spin-echo pulse sequences. Mathematical models were used to describe the spatial and temporal velocity distributions of human brain motion. The spatial distribution of brain-tissue velocity introduces a phase spread over one voxel, leading to signal loss. This signal loss was estimated theoretically, and effe

Shaping Stable Periodic Motions of Inertia Wheel Pendulum: Theory And Experiment

We consider an underactuated two-link robot called the inertia wheel pendulum. The system consists of a free planar rotational pendulum and a symmetric disk attached to its end, which is directly controlled by a DC-motor. The goal is to create stable oscillations of the pendulum, which is not directly actuated. We exploit a recently proposed feedback-control design strategy based on motion plannin

Titanium-hydrogen peroxide interaction: model studies of the influence of the inflammatory response on titanium implants

In vitro studies of titanium and TiO2 as well as other metals were carried out to investigate the role of these metals in the inflammatory response through the Fenton reaction. The TiOOH matrix formed traps the superoxide radical, so that no or very small amounts of free hydroxyl radicals are produced. Ellipsometry and spin trapping with spectrophotometry and electron spin resonance (ESR) were use

Development of an H-TDMA for long-term unattended measurement of the hygroscopic properties of atmospheric aerosol particles

A new hygroscopic tandem differential mobility analyzer (H-TDMA) has been constructed at Lund University within the frameworks of the EU FP6 Infrastructure Project EUSAAR (www.eusaar.org). The aim of this coordinated H-TDMA development is to design and evaluate a new generation of H-TDMAs that are capable of conducting long term measurements of the hygroscopic growth and state of mixing of sub-mic

Do coupling exciton and oscillation of electron-hole pair exist in neutral and charged pi-dimeric quinquethiophenes?

Optical physical properties of neutral and charged quinquethiophene monomer, and neutral and cationic pi-dimeric quinquethiophenes were investigated with density functional theory as well as the two dimensional (2D) site (transition density matrix) and three dimensional (3D) cube (transition density and charge difference density) representations, stimulated by the recent experimental report [T. Sa

Spreading Dynamics of a Functionalized Polymer Latex.

Functionalized polymer nanoparticles are used as binders for inorganic materials in everyday technologies such as paper and coatings. However, the functionalization can give rise to two opposing effects: It can promote adhesion via specific interactions to the substrate, but a high degree of functionalization can also hamper spreading on substrates. Here, we studied the spreading kinetics of indiv

Cerebral changes after injury to the median nerve: A long-term follow up

Injury to the peripheral nerves in the upper extremity results in changes in the nerve, and at multiple sites throughout the central nervous system (CNS). We studied the long-term effects of an injury to the median nerve in the forearm with a focus on changes in the CNS. Four patients with isolated injuries of the median nerve in their 20s were examined a mean of 14 years after the injury. Cortica

Effects on blood pressure in patients with refractory angina pectoris after enhanced external counterpulsation

Objective. Enhanced external counterpulsation (EECP) is a non-invasive technique that has been shown to reduce the frequency and severity of angina pectoris. Little is known how EECP affects the blood pressure. Methods. 153 patients with refractory angina were treated with either EECP or retained on their pharmacological treatment (reference group). Systolic blood pressure (SBP), diastolic blood p

Rates of visual field progression in clinical glaucoma care.

Purpose: To investigate rates of visual field progression and factors associated with progression rate in open-angle glaucoma in clinical glaucoma care. Methods: We performed a retrospective chart review of all patients with manifest primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (PEXG) followed ≥ 5 years with ≥5 SITA Standard fields. Exclusion criteria were minimal. Demographic

Thermopower as a tool to investigate many-body effects in quantum systems

Measuring the thermopower of a confined quantum system reveals important information about its excitation spectrum. Our simulations show how this kind of transport spectroscopy is able to extract a clear signal for the onset of Wigner localization in a nanowire segment. This demonstrates that thermopower measurements provide a tool for investigating complex many-body quantum effects, which is less

Acinar ventilation heterogeneity in COPD relates to diffusion capacity, resistance and reactance.

The aim of this study was to investigate heterogenic ventilation in the acinar (Sacin) and conductive (Scond) airways of patients with varying chronic obstructive pulmonary disease (COPD) severity and how these relates to advanced lung function parameters, primarily measured by impulse oscillometry (IOS). A secondary aim was to investigate the effects of a short acting beta2-agonist and a muscarin

A methodology for estimating risks associated with landslides of contaminated soil into rivers.

Urban areas adjacent to surface water are exposed to soil movements such as erosion and slope failures (landslides). A landslide is a potential mechanism for mobilisation and spreading of pollutants. This mechanism is in general not included in environmental risk assessments for contaminated sites, and the consequences associated with contamination in the soil are typically not considered in lands

Single injections of apoA-I acutely improve in vivo glucose tolerance in insulin-resistant mice.

Apolipoprotein A-I (apoA-I), the main protein constituent of HDL, has a central role in the reverse cholesterol-transport pathway, which together with the anti-inflammatory properties of apoA-I/HDL provide cardioprotection. Recent findings of direct stimulation of glucose uptake in muscle by apoA-I/HDL suggest that altered apoA-I and HDL functionality may be a contributing factor to the developmen

Phylogeography of the freshwater raphidophyte Gonyostomum semen confirms a recent expansion in northern Europe by a single haplotype

Gonyostmum semen is a freshwater raphidophyte that has increased in occurrence and abundance in several countries in northern Europe since the 1980s. More recently, the species has expanded rapidly also in north-eastern Europe, and it is frequently referred to as invasive. To better understand the species history, we have explored the phylogeography of G. semen using strains from northern Europe,