Publications by authors named "Dennis Nelson"

Background: Robust approaches to quantify tumor heterogeneity are needed to provide early decision support for precise individualized therapy.

Purpose: To conduct a technical exploration of longitudinal changes in tumor heterogeneity patterns on dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI) and FDG positron emission tomography / computed tomography (PET/CT), and their association to radiation therapy (RT) response in cervical cancer.

Study Type: Prospective observational study with longitudinal MRI and PET/CT pre-RT, early-RT (2 weeks), and mid-RT (5 weeks).

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Purpose: To determine the extent of variations in computing standardized uptake value (SUV) by body weight (SUV(BW)) among different software packages and to propose a Digital Imaging and Communications in Medicine (DICOM) reference test object to ensure the standardization of SUV computation between medical image viewing workstations.

Materials And Methods: Research ethics board approval was not necessary because this study only evaluated images of a phantom. A synthetic set of positron emission tomographic (PET)/computed tomographic (CT) image data, called a digital reference object (DRO), with known SUV was created.

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Aquifer storage and recovery (ASR) can provide a means of storing water for irrigation in agricultural areas where water availability is limited. A concern, however, is that the injected water may lead to a degradation of groundwater quality. In many agricultural areas, nitrate is a limiting factor.

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Purpose: To determine the efficacy of a Gamma Knife stereotactic radiosurgery (SRS) boost to areas of high risk determined by magnetic resonance spectroscopy (MRS) functional imaging in addition to standard radiotherapy for patients with glioblastoma (GBM).

Methods And Materials: Thirty-five patients in this prospective Phase II trial underwent surgical resection or biopsy for a GBM followed by SRS directed toward areas of MRS-determined high biological activity within 2 cm of the postoperative enhancing surgical bed. The MRS regions were determined by identifying those voxels within the postoperative T2 magnetic resonance imaging volume that contained an elevated choline/N-acetylaspartate ratio in excess of 2:1.

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The ultrastructural morphology of the mouthparts of the glassy-winged sharpshooter, Homalodisca coagulata, and method of plant penetration was examined using light microscopy, scanning electron microscopy, and transmission electron microscopy methods. The gross morphology of the labrum, labium, and stylet fascicle was consistent with what has been described for other plant-sucking homopterans. The ultrastructural examination of the mouthparts revealed unique details that have previously gone unreported.

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The primary objective of this overview is to apprise clinical urologists and oncologists of the current state of fused multimodality imaging of prostate cancer, which can be applied to optimize treatment by ensuring that a patient's disease is characterized as well as current imaging technology permits. The focus of this study is the monoclonal antibody capromab pendetide, which targets prostate specific membrane antigen (PSMA), a type II membrane glycoprotein strongly associated with prostate cancer. Identifying where capromab pendetide uptake occurs can be done accurately if this functional imaging modality is combined with a modality that provides anatomic detail, such as computed tomography (CT) or magnetic resonance imaging (MRI).

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Within their gall, larvae of the goldenrod gall fly (Eurosta solidaginis) experience severe desiccating conditions as well as highly variable thermal conditions and extreme cold during winter. Through the autumn and early winter, field-collected larvae acquired markedly enhanced resistance to desiccation and freezing. At the same time, they increased their cuticular surface hydrocarbons.

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The viviparous cockroach Diploptera punctata carries a wax-coated batch of embryos in a brood sac. When the embryos are expelled into saline, flakes of wax from the surface of the embryos float to the surface. In contrast, embryos of the ovoviviparous species such as Rhyparobia maderae are not nourished by the mother during embryogenesis and do not have a copious waxy coating.

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The adult dustywing, Semidalis flinti Meinander (Neuroptera: Coniopterygidae), begins producing circular-shaped waxy particles after eclosion. The waxy material, which forms the particles, is extruded from individual pores found in clusters on the abdomen. Pores also are present in two rows of three pores on the frontalis and two pores on the first segment of each antennae.

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Hydrocarbons were the major lipid class extracted by hexane from the vitelline membrane surface of dechorionated eggs of the house fly, Musca domestica, the New World screwworm, Cochliomyia hominivorax, the secondary screwworm, Cochliomyia macellaria, the green bottle fly, Phaenicia sericata, the sheep blow fly, Lucilia cuprina and the Mexican fruit fly, Anastrepha ludens. The length of time the embryos must be exposed to hexane with or without a small amount of alcohol in order to attain permeability was species-dependant. Long-chain n-alkanes comprised the major lipid class removed from vitelline membranes of all species except A.

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Hydrocarbons were the major lipid class on the cuticular surface of adults, nymphs, and eggs of the sunflower beetle, Zygogramma exclamationis, characterized by gas chromatography-mass spectrometry. Minor amounts of wax ester from 40 to 48 carbon atoms in size were only detected in larvae. The hydrocarbons ranged in size from 23 carbons (tricosene) to 56 carbons (trimethyltripentacontane) and were largely methylalkanes.

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The major components of the egg hydrocarbons were dimethylalkanes (40%) and trimethylalkanes (24%) in which the first methyl branch was on carbon 2. The major dimethylalkanes were an approximately 2:1 mixture of 2,10- and 2,6-dimethyloctacosanes in females and eggs. The major trimethylalkanes were a mixture of 2,10,16- and 2,10,18-trimethyloctacosanes.

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The adult beetles Aphthona lacertosa and Aphthona nigriscutis, used as biocontrol agents for leafy spurge, had a complex mixture of hydrocarbons on their cuticular surface consisting of alkanes, methylalkanes, alkenes and alkadienes as determined by gas chromatography-mass spectrometry. A trace amount of wax esters were present. In both species, the hydrocarbons were the major cuticular lipid class and the gas chromatographic profiles of the total hydrocarbons were similar.

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