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AS3MT-mediated tolerance to arsenic evolved by multiple independent horizontal gene transfers from bacteria to eukaryotes

Organisms have evolved the ability to tolerate toxic substances in their environments, often by producing metabolic enzymes that efficiently detoxify the toxicant. Inorganic arsenic is one of the most toxic and carcinogenic substances in the environment, but many organisms, including humans, metabolise inorganic arsenic to less toxic metabolites. This multistep process produces mono-, di-, and tri

Practical Evaluation of a Novel Multivariable Relay Autotuner with Short and Efficient Excitation

In this paper we propose an autotuning method that combines a setup for decentralized relay autotuning of two-input two-output systems with an identification method that uses short experiments to estimate up to second-ordertime-delayed systems. A small modification of the experiment gives better low-frequency excitation and improved models. The method is successfully demonstrated in simulations an

Wash-in and wash-out of sevoflurane in a test-lung model : A comparison between Aisys and FLOW-i

Background: Modern anaesthesia workstations are reassuringly tight and are equipped with effective gas monitoring, thus providing good opportunities for low/minimal flow anaesthesia. A prerequisite for effective low flow anaesthesia is the possibility to rapidly increase and decrease gas concentrations in the circle system, thereby controlling the depth of anaesthesia. Methods: We studied the wash

Short and Robust Experiments in Relay Autotuners

This paper demonstrates how second-order time-delayed models adequate for PID controller synthesis can be identified from significantly shorter relay experiments, than used in previous publications to obtain first-order time-delayed models. Apart from having good noise robustness properties, the proposed method explicitly addresses non-stationary initial states of the dynamics to be identified, an

Neck-Related Physical Function, Self-Efficacy, and Coping Strategies in Patients With Cervical Radiculopathy : A Randomized Clinical Trial of Postoperative Physiotherapy

Objective: The purpose of this study was to compare postoperative rehabilitation with structured physiotherapy to the standard approach in patients with cervical radiculopathy (CR) in a prospective randomized study at 6 months follow-up based on measures of neck-related physical function, self-efficacy, and coping strategies. Methods: Patients with persistent CR and scheduled for surgery (N = 202)

Device-Aided Treatment Strategies in Advanced Parkinson's Disease

With peroral levodopa treatment, a majority of patients develop motor fluctuations and dyskinesia already within a few years of therapy. Device-aided Parkinson (PD) therapies refer to deep brain stimulation (DBS), levodopa-carbidopa intestinal gel infusion (LCIG), and subcutaneous infusion of the dopamine agonist apomorphine and represent effective strategies counteracting motor fluctuations and d

Source deghosting

Marine seismic data are distorted by ghosts as waves propagating upwards reflect downwards from the sea surface. Ghosts appear both on the source-side as well as on the receiver-side. However, whereas the receiver-side ghost problem has been studied in detail and many different solutions have been proposed and implemented commercially, the source-side ghost problem has remained largely "unsolved"

Aperiodic wavefield signal apparition : De-aliased simultaneous source separation

In wavefield signal apparition, acquisition with periodic variations in source activation parameters shifts all or part of a signal cone out to, e.g., the Nyquist wavenumber, enabling perfect separation of simultaneous-source (sim-source) data below a certain temporal frequency. Cyclic convolution in the spatial frequency domain is used to generalise the signal apparition concept to the case of ap

The structure-tensor analysis for optimal microseismic data partial stack

Microseismic monitoring of hydrofrac is an actively developing technology utilizing various acquizition arrays. In this paper we consider processing of microseismic data recorded by specific surface network geometry-patch arrays (far separated local receiver groups). The project aim is to produce an optimal partial stacking of the data within patches for improving a signal to noise ratio for micro

Brand Theories : Perspectives on Brands and Branding

Brand Theories offers a multifaceted understanding of brands and branding. The purpose of the book is to provide the reader with a more advanced knowledge, by treating brands and branding from three differrent perspectives: a brand management perspective, a consumer perspective, and a critical perspective.By allow readers to shift perspectives, the book offers the unique opportunity to analyze and

Retinal Glial (Müller) Cells : Sensing and responding to tissue stretch

Purpose. To test whether Müller glial cells sense, and respond to, mechanical tension in the retina. Methods. A device was designed to stretch the retina at right angles to its surface, across retinal layers. Pieces of retina were mounted between two hollow tubes, and uniaxial force was applied to the tissue using a micrometer-stepping motor. Müller cells were selectively stained with the fluoresc

Inheritance of acquired behaviour adaptations and brain gene expression in chickens

Background: Environmental challenges may affect both the exposed individuals and their offspring. We investigated possible adaptive aspects of such cross-generation transmissions, and hypothesized that chronic unpredictable food access would cause chickens to show a more conservative feeding strategy and to be more dominant, and that these adaptations would be transmitted to the offspring. Methodo