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Quantification of absolute myocardial perfusion in patients with coronary artery disease: comparison between cardiovascular magnetic resonance and positron emission tomography

OBJECTIVES: The aim of this study was to compare fully quantitative cardiovascular magnetic resonance (CMR) and positron emission tomography (PET) myocardial perfusion and myocardial perfusion reserve (MPR) measurements in patients with coronary artery disease (CAD).BACKGROUND: Absolute quantification of myocardial perfusion and MPR with PET have proven diagnostic and prognostic roles in patients

A fully automatic algorithm for assessing T2* and its certainty value for accurate cardiac and liver iron load determination

Quantification of myocardial and liver iron load has become a mainstay of guiding therapy in thalassaemia patients. However, current quantification methods are user dependent for data-point exclusion before curve fitting, and do not report the T2* certainty. Recently, an automatic inline maximum likelihood estimate (MLE) method with k-space Rician noise correction was validated against the referen

Imaging Non-Local Magnetization Dynamics

Many fundamental processes in magnetism take place on a nanometer length and sub-picosecond time scale. An important example of such phenomena in magnetism is ultrafast, spin-polarized transport of laser-excited hot electrons, which is now being recognized as playing a crucial role for novel spintronic devices and for optically induced magnetic switching. Recent experimental examples include the d

Automatic T2* determination for quantification of iron load in heart and liver : a comparison between automatic inline Maximum Likelihood Estimate and the truncation and offset methods

PURPOSE: To validate ironload T2* by automatic inline Maximum Likelihood Estimate (MLE) with k-space Rician noise correction, against the manual and automated truncation, as well as offset methods, in phantoms and in heart and liver in patients.METHODS: Twenty-five patients and an iron-oxide phantom were scanned at 1.5T using 2 multi-echo gradient-echo sequences. All parameters were identical (vox

Carbon and nitrogen stable isotope values in freshwater, brackish and marine fish bone collagen from Mesolithic and Neolithic sites in central and northern Europe

The aim of this research is to examine the isotopic characterisation of archaeological fish species as it relates to freshwater, brackish and marine environments, trophic level and migration patterns, and to determine intraspecies variation within and between fish populations in different locations within central and northern Europe. Carbon and nitrogen stable isotope analysis was undertaken on co

Improvement of whole-cell transamination with Saccharomyces cerevisiae using metabolic engineering and cell pre-adaptation

Background: Whole-cell biocatalysis based on metabolically active baker's yeast with engineered transamination activity can be used to generate molecules carrying a chiral amine moiety. A prerequisite is though to express efficient ω-transaminases and to reach sufficient intracellular precursor levels. Results: Herein, the efficiency of three different ω-transaminases originating from Capsicum chi

Experimental methods and modeling techniques for description of cell population heterogeneity

With the continuous development, in the last decades, of analytical techniques providing complex information at single cell level, the study of cell heterogeneity has been the focus of several research projects within analytical biotechnology. Nonetheless, the complex interplay between environmental changes and cellular responses is yet not fully understood, and the integration of this new knowled

Assessing vector navigation in long-distance migrating birds

Birds migrating between distant locations regularly perform long continuous flights lasting several days. What compass mechanism they use is still a mystery. Here, we use a novel approach, applying an individual-based model, taking compass mechanisms based on celestial and geomagnetic information and wind into account simultaneously, to investigate what compass mechanism likely is used during long

Visual navigation in nocturnal insects

Despite their tiny eyes and brains, nocturnal insects have evolved a remarkable capacity to visually navigate at night. Whereas some use moonlight or the stars as celestial compass cues to maintain a straight-line course, others use visual landmarks to navigate to and from their nest. These impressive abilities rely on highly sensitive compound eyes and specialized visual processing strategies in

Incorporating Affective Aspects into Pedagogy

Human-Computer Interaction (HCI) is an umbrella domain for many areas of study. This paper will look at those topics of HCI known as affective aspects. Affective aspects investigate emotional responses that the user communicates, both verbally and physically, when working with a computer including before and after the work is done. This paper examines the question of improving pedagogy and curricu

Solving large instances of the RSA problem in flexgrid elastic optical networks

We present an optimization procedure that mixes advanced large-scale optimization methods and heuristics to solve large instances (with over 1.7 million integer variables) of the routing and spectrum allocation (RSA) problem - a basic optimization problem in flexgrid elastic optical networks. We formulate the problem as a mixed-integer program for which we develop a branch-and-price algorithm enha

Acoustofluidic harvesting of microalgae on a single chip

We present an on-chip acoustofluidic platform for harvesting a target microalgal species from a heterogeneous population of cells and particles based on their size, density, and compressibility in a rapid, non-invasive, energy-efficient, continuously running, and automated manner. For our proof-of-principle demonstration, we use Euglena gracilis as a target species. Specifically, we show the simul

Bats may eat diurnal flies that rest on wind turbines

Bats are currently killed in large numbers at wind turbines worldwide, but the ultimate reason why this happens remains poorly understood. One hypothesis is that bats visit wind turbines to feed on insects exposed at the turbine towers. We used single molecule next generation DNA sequencing to identify stomach contents of 18 bats of four species (Pipistrellus pygmaeus, Nyctalus noctula, Eptesicus

Microsieving in municipal wastewater treatment : Chemically enhanced primary and tertiary treatment

Municipal wastewater treatment plants are constantly forced to make improvements. The main objectives are to reduce energy consumption, to increase the treatment capacity and to improve the effluent water quality. Microsieves in combination with chemical pretreatment can potentially fulfil these objectives. In this work, experiments were mainly conducted at the large pilot scale, and supplementaryMunicipal wastewater treatment plants are constantly forced to make improvements. The main objectives are to reduce energy consumption, to increase the treatment capacity and to improve the effluent water quality. Microsieves in combination with chemical pretreatment can potentially fulfil these objectives. In this work, experiments were mainly conducted at the large pilot scale, and supplementary