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Correction for Residual Effects of B1+ Inhomogeniety on MT Saturation in FLASH-Based Multi-Parameter Mapping of the Brain

Maps of the MT-saturation as derived in FLASH-based multi-parameter mapping (MPM) are largely corrected for effects of flip angle inhomogeneity. Here, we present a heuristic model for residual effects of B1+ that is rooted in the dynamics of macromolecule saturation. Model parameters were validated for brain tissues by variation of the MT-pulse flip angle in an established MPM protocol. White and

Description and calibration of the ISO tapping machine in numerical impact sound predictive tools

One of the challenges in wooden constructions is to be able to achieve a good acoustic insulation especially in the low frequency range. The prediction of acoustic performance of wooden buildings before erection becomes important and reliable predictive tools are in great need. To that end, the first question that arises is how to accurately model the excitation source which generates the structur

OSL PROPERTIES IN VARIOUS FORMS OF KCl AND NaCl SAMPLES AFTER EXPOSURE TO IONIZING RADIATION

The aim of this work was to investigate the optically-stimulated luminescence (OSL) properties of potassium chloride (KCl) and its potential use in radiation dosimetry. The optimal condition for OSL readout with blue light stimulation were designated using a commercially available Risø TL/OSL reader. KCl was studied in three sample forms: crystals, powder and pellets. The following OSL characteris

Introducing the concept of the isodose for optimisation of decontamination activities in a radioactive fallout scenario

In the recovery phase after a radioactive release incident, it is important to be able to focus decontamination operations on the areas that contribute most to the radiation dose. Monte Carlo simulations were applied to determine the shielding effect of a building against radiation from various directions, also giving information on the dose contributions at various locations inside the building f

Modeling walking on a lightweight wooden floor

The most common sound insulation problem for lightweight timber structures is impact sounds from people walking. This is especially apparent in the low frequency range, due to differences in weight, stiffness, density and repartitioning as compared to more traditional materials. As lightweight timber structures increase their market share, the understanding of their behaviour and the ability to pr

Excretion Rate and Distribution Volumes in Common Marmoset Monkeys After Slow and Fast Injection of Gadobutrol

Common marmoset monkeys (Callithrix jacchus) are increasingly used in models of neurodegenerative diseases. Serial measurements of gadolinium excretion were performed using the dual flip angle method to map R1 on three animals in the wrist coil of a 3T whole-body system. R1 values were analyzed in a ROI in the straight sinus and fitted with a single compartment model. Slow injection of 0.3 mmol Ga

Twenty-first century remote sensing technologies are revolutionizing the study of tropical forests

The fields of tropical biology and conservation face significant transformations due to rapid technological developments in remote sensing. Other fields (e.g. Archeology) are experiencing this momentous change even more rapidly. In this article, we review some of the challenges that the fields of tropical biology and conservation face during the first quarter of the twenty-first century from the p

Quantifying changes on forest succession in a dry tropical forest using angular-hyperspectral remote sensing

The tropical dry forest (TDF) is one the most threatened ecosystems in South America, existing on a landscape with different levels of ecological succession. Among satellites dedicated to Earth observation and monitoring ecosystem succession, CHRIS/PROBA is the only satellite that presents quasi-simultaneous multi-angular pointing and hyperspectral imaging. These two characteristics permit the stu

Monitoring Flooding Damages in Vegetation Caused by Mining Activities Using Optical Remote Sensing

Ground removal during the mineral extraction in mine galleries provokes permanent changes in ground compacting during mine exploitation and after mine closure. In extreme cases, the loss of cohesion in ground layer over mines causes surface subsidence and eventually the emergence of flooded areas on the surface. Mining companies are obligated to the surveillance and mending of damages caused by th

Target detection of mine-related flooded areas using AISA-eagle data

The present research is developed in the frame of the R&D project GMES4Mining, which aims to support particular tasks within the different phases of a mining life cycle [1]. During the exploitation and after the closure of the mine, environmental and civil impacts may happen, due to changes in the compacting properties of the soil related to mining activities. In this paper, we focus in the em

Multi-Temporal Monitoring Of Ecological Succession In Tropical Dry Forests Using Angular-Hyperspectral Data (Chris/Proba)

The tropical dry forest is the largest and most threatened ecosystem in Latin America. Remote sensing can effectively contribute to the surveillance of conservation measurements and laws through the monitoring of natural protected areas, at the required temporal and spatial scales. CHRIS/PROBA is the only satellite that presents quasi-simultaneous multi-angular pointing and hyperspectral spectrosc

Light–dependent effects of zinc protoporphyrin IX on endothelium–dependent relaxation resistant to NoM–nitro–L–arginine

Acetylcholine (ACh) induces an Nω–nitro–L–arginine (L–NOARG)–resistant relaxation and hyperpolarization in the rat isolated hepatic artery. The possibility that carbon monoxide (CO) produced by haem oxygenase (HO) is an endogenous mediator of this response was investigated. Exogenously applied CO evoked a concentration–dependent relaxation, and the CO ‘scavenger’ oxyhaemoglobin (10μM) reduced the

The endothelium mediates a nitric oxide‐independent hyperpolarization and relaxation in the rat hepatic artery

The rat hepatic artery responds to acetylcholine (ACh) with an endothelium‐dependent relaxation, which is unaffected by nitric oxide (NO) synthase and cyclooxygenase inhibition. The purpose of this study was to investigate whether the NO‐independent relaxation is caused by hyperpolarization of the smooth muscle cells. In vessels with endothelium ACh induced a hyperpolarization in the presence of 0

Effects of ω‐conotoxin on adrenergic, cholinergic and NANC neurotransmission in the rabbit urethra and detrusor

The effects of ω‐conotoxin GVIA (an inhibitor of N‐type voltage‐operated calcium channels; VOCCs) were compared on adrenergic, cholinergic and non‐adrenergic, non‐cholinergic (NANC) responses induced by electrical field stimulation (EFS) in the rabbit urethra and detrusor. EFS induced a relaxation in urethral smooth muscle and lamina propria precontracted by arginine vasopressin (AVP). The relaxat