Publications by authors named "Hopp T"

The isotopic compositions of samples returned from Cb-type asteroid Ryugu and Ivuna-type (CI) chondrites are distinct from other carbonaceous chondrites, which has led to the suggestion that Ryugu/CI chondrites formed in a different region of the accretion disk, possibly around the orbits of Uranus and Neptune. We show that, like for Fe, Ryugu and CI chondrites also have indistinguishable Ni isotope anomalies, which differ from those of other carbonaceous chondrites. We propose that this unique Fe and Ni isotopic composition reflects different accretion efficiencies of small FeNi metal grains among the carbonaceous chondrite parent bodies.

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The Moon has a tenuous atmosphere produced by space weathering. The short-lived nature of the atoms surrounding the Moon necessitates continuous replenishment from lunar regolith through mechanisms such as micrometeorite impacts, ion sputtering, and photon-stimulated desorption. Despite advances, previous remote sensing and space mission data have not conclusively disentangled the contributions of these processes.

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Prior work on the relationship between general social media use and political knowledge has yielded mixed findings. One recent meta-analysis on the topic concluded that the literature, when assessed as a whole, fails to indicate a direct and statistically identifiable between relationship general social media use and political knowledge. Considering these findings, the present work sought to assess the extent to which general social media use might be conditionall related to political knowledge.

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Background: A typical problem in the registration of MRI and X-ray mammography is the nonlinear deformation applied to the breast during mammography. We have developed a method for virtual deformation of the breast using a biomechanical model automatically constructed from MRI. The virtual deformation is applied in two steps: unloaded state estimation and compression simulation.

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Ultrasound tomography (USCT) is a promising imaging modality, mainly aiming at early diagnosis of breast cancer. It provides three-dimensional, reproducible images of higher quality than conventional ultrasound methods and additionally offers quantitative information on tissue properties. This chapter provides an introduction to the background and history of USCT, followed by an overview of image reconstruction algorithms and system design.

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This report describes proteolytic fragmentation and clearance of bovine lactoferrin (bLF) upon intravaginal administration in premenopausal women. Tablet formulations (MTbLF) containing 300 mg of bLF progressed through three phases: Pre-Dissolution, Dissolution, and Washout, over a 30-h time course. Tablets dissolved slowly, replenishing intact 80 kDa bLF in vaginal fluid (VF) as proteolysis occurred.

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. The image reconstruction of ultrasound computed tomography is computationally expensive with conventional iterative methods. The fully learned direct deep learning reconstruction is promising to speed up image reconstruction significantly.

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Little is known about the origin of the spectral diversity of asteroids and what it says about conditions in the protoplanetary disk. Here, we show that samples returned from Cb-type asteroid Ryugu have Fe isotopic anomalies indistinguishable from Ivuna-type (CI) chondrites, which are distinct from all other carbonaceous chondrites. Iron isotopes, therefore, demonstrate that Ryugu and CI chondrites formed in a reservoir that was different from the source regions of other carbonaceous asteroids.

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Industry-specific safety climate scales that measure safety status have been published, however, nothing specific to biological laboratories has ever been established. This study aimed to develop and validate a biosafety climate (BSCL) scale unique for research professionals (RPs) and biosafety professionals (BPs) at teaching and research biological laboratories affiliated to public universities in the United States. BSCL scale was developed from literature review.

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When bovine lactoferrin (bLF) contacts human vaginal fluid (VF) it is subjected to proteolytic degradation. This report describes fragmentation patterns of bLF dosed vaginally in clinical trials or incubated ex vivo with VF. A consensus pattern of fragments was observed in samples from different women.

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Chondrites display isotopic variations for moderately volatile elements, the origin of which is uncertain and could have involved evaporation/condensation processes in the protoplanetary disk, incomplete mixing of the products of stellar nucleosynthesis, or aqueous alteration on parent bodies. Here, we report high-precision K and Rb isotopic data of carbonaceous chondrites, providing new insights into the cause of these isotopic variations. We find that the K and Rb isotopic compositions of carbonaceous chondrites correlate with their abundance depletions, the fractions of matrix material, and previously measured Te and Zn isotopic compositions.

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Image reconstruction of ultrasound computed tomography based on the wave equation is able to show much more structural details than simpler ray-based image reconstruction methods. However, to invert the wave-based forward model is computationally demanding. To address this problem, we develop an efficient fully learned image reconstruction method based on a convolutional neural network.

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Understanding the circumstances of the undeclared 2017 nuclear release of ruthenium that led to widespread detections of the radioisotope Ru in the Eurasian region, and whether it derives from a civilian or military source, is of major importance for society and future improvements in nuclear safety. Until now, the released nuclear material has merely been studied by analyzing short-lived radioisotopes. Here, we report precise measurements of the stable isotopic composition of ruthenium captured in air filters before, during, and after the nuclear release, and find that the ruthenium collected during the period of the 2017 nuclear release has a non-natural isotopic composition.

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This study explored the relationship between interdependent self-construal, video game self-efficacy, massively multiplayer online role-playing game (MMORPG) community involvement, and self-reported learning outcomes. The results suggested that self-efficacy and interdependent self-construal were positive and significant predictors of MMORPG community involvement. For its part, MMORPG community involvement was a positive predictor of self-reported learning in both focused and incidental forms.

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Purpose: 4D co-registration of X-ray- and MR-mammograms (XM and MM) is a new method of image fusion. The present study aims to evaluate its clinical feasibility, radiological accuracy, and potential clinical value.

Methods: XM and MM of 25 patients were co-registered.

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Ultrasound Computer Tomography (USCT) is a promising breast imaging modality under development. Comparison to a standard method like mammography is essential for further development. Due to significant differences in image dimensionality and compression state of the breast, correlating USCT images and X-ray mammograms is challenging.

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A promising candidate for imaging of breast cancer is ultrasound computer tomography (USCT). The main advantages of a USCT system are simultaneous recording of reproducible reflection, attenuation and speed of sound volumes, high image quality, and fast data acquisition. The here presented 3D USCT prototype realizes for the first time the full potential of such a device.

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Due to their different physical origin, X-ray mammography and Magnetic Resonance Imaging (MRI) provide complementary diagnostic information. However, the correlation of their images is challenging due to differences in dimensionality, patient positioning and compression state of the breast. Our automated registration takes over part of the correlation task.

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Purpose: Breast cancer is the most common cancer among women. The established screening method to detect breast cancer is X-ray mammography. Additionally, MRI is used for diagnosis in clinical routine.

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Rationale And Objectives: To evaluate the semi-automatic image registration accuracy of X-ray-mammography (XR-M) with high-resolution high-field (3.0T) MR-mammography (MR-M) in an initial pilot study.

Material And Methods: MR-M was acquired on a high-field clinical scanner at 3.

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Estrogen receptor alpha (ERalpha) is highly regulated through multiple mechanisms including cell signaling, posttranslational modifications, and protein-protein interactions. We have previously identified a K303R ERalpha mutation within the hinge region of ERalpha. This mutation results in an altered posttranslational regulation and increased in vitro growth in the presence of low estrogen concentrations.

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We identified a somatic mutation in estrogen receptor-alpha (ERalpha) in breast cancer causing a lysine to arginine transition (K303R) resulting in hypersensitivity to estrogen, altered associations with coactivators and corepressors and altered posttranslational modifications of ERalpha. We have developed a transgenic mouse expressing the K303R mutant ERalpha under control of the mouse mammary tumor virus (MMTV) promoter. At 4 months of age, K303R ERalpha transgenic animals demonstrate precocious alveolar budding compared with wild-type ERalpha transgenic mice or nontransgenic littermates.

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Background: Much of the research on cognitive pharmaceutical services has focused on understanding or changing community pharmacist behaviour, with few studies focusing on the pharmacy as the unit of analysis or considering the whole profession as an organisation.

Objectives: To investigate practice change and identify facilitators of this process in community pharmacy, with specific focus on the implementation of cognitive pharmaceutical services (CPS) and related programs.

Methods: Thirty-six in-depth, semistructured interviews were conducted with participants from 2 groups, community pharmacies and pharmacy "strategists," in Australia.

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