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  1. Article: [Rezension von: McPherson, Michael S., ..., Keeping college affordable]

    Hansen, W. L / McPherson, Michael S

    Journal of economic literature 31 ,2, S. 906-907

    1993  

    Author's details W. Lee Hansen
    Keywords 40;49
    Language English
    Publisher Assoc
    Publishing place Nashville, Tenn
    Document type Article
    ZDB-ID 3076-4 ; 2010159-4
    ISSN 0022-0515
    ISSN 0022-0515
    Database ECONomics Information System

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  2. Book ; Online: Trace element composition of IODP Site 304-U1309 and 305-U1309 (Table A2), supplementary data to: Godard, Marguerite; Awaji, S; Hansen, H; Hellebrand, Eric; Brunelli, D; Johnson, K; Yamasaki, T; Maeda, Jinichiro; Abratis, Michael; Christie, David M; Kato, Yasuhiro; Mariet, C; Rosner, Martin (2009): Geochemistry of a long in-situ section of intrusive slow-spread oceanic lithosphere: Results from IODP Site U1309 (Atlantis Massif, 30?N Mid-Atlantic-Ridge). Earth and Planetary Science Letters, 279(1-2), 110-122

    Godard, Marguerite / Abratis, Michael / Awaji, S / Brunelli, D / Hansen, H / Hellebrand, Eric / Johnson, K / Maeda, Jinichiro / Yamasaki, T / al., et

    2009  

    Abstract: IODP Site U1309 was drilled at Atlantis Massif, an oceanic core complex, at 30?N on the Mid-Atlantic Ridge (MAR). We present the results of a bulk rock geochemical study (major and trace elements) carried out on 228 samples representative of the ... ...

    Abstract IODP Site U1309 was drilled at Atlantis Massif, an oceanic core complex, at 30?N on the Mid-Atlantic Ridge (MAR). We present the results of a bulk rock geochemical study (major and trace elements) carried out on 228 samples representative of the different lithologies sampled at this location.
    Over 96% of Hole U1309D is made up of gabbroic rocks. Diabases and basalts cross-cut the upper part of the section; they have depleted MORB compositions similar to basalts sampled at MAR 30?N. Relics of mantle were recovered at shallow depth. Mantle peridotites show petrographic and geochemical evidence of extensive melt-rock interactions. Gabbroic rocks comprise: olivine-rich troctolites (> 70% modal olivine) and troctolites having high Mg# (82-89), high Ni (up to 2300 ppm) and depleted trace element compositions (Yb 0.06-0.8 ppm); olivine gabbros and gabbros (including gabbronorites) with Mg# of 60-86 and low trace element contents (Yb 0.125-2.5 ppm); and oxide gabbros and leucocratic dykes with low Mg# (< 50), low Ni (~65 ppm) and high trace element contents (Yb up to 26 ppm). Troctolites and gabbros are amongst the most primitive and depleted oceanic gabbroic rocks. The main geochemical characteristics of Site U1309 gabbroic rocks are consistent with a formation as a cumulate sequence after a common parental MORB melt, although (lack of systematic) downhole variations indicate that the gabbroic series were built by multiple magma injections. In detail, textural and geochemical variations in olivine-rich troctolites and gabbronorites suggest chemical interaction (assimilation?) between the parental melt and the intruded lithosphere.
    Site U1309 gabbroic rocks do not represent the complementary magmatic product of 30?N volcanics, although they sample the same mantle source. The bulk trace element composition of Site U1309 gabbroic rocks is similar to primitive MORB melt compositions; this implies that there was no large scale removal of melts from this gabbro section. The occurrence of such a large magmatic sequence implies that a high magmatic activity is associated with the formation of Atlantis Massif. Our results suggest that almost all melts feeding this magmatic system stays trapped into the intruded lithosphere.
    Language English
    Dates of publication 2009-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1016/j.epsl.2008.12.034
    DOI 10.1594/PANGAEA.723697
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  3. Article ; Online: A Path Towards Clinical Adaptation of Accelerated MRI.

    Yao, Michael S / Hansen, Michael S

    Proceedings of machine learning research

    2023  Volume 193, Page(s) 489–511

    Abstract: Accelerated MRI reconstructs images of clinical anatomies from sparsely sampled signal data to reduce patient scan times. While recent works have leveraged deep learning to accomplish this task, such approaches have often only been explored in simulated ... ...

    Abstract Accelerated MRI reconstructs images of clinical anatomies from sparsely sampled signal data to reduce patient scan times. While recent works have leveraged deep learning to accomplish this task, such approaches have often only been explored in simulated environments where there is no signal corruption or resource limitations. In this work, we explore augmentations to neural network MRI image reconstructors to enhance their clinical relevancy. Namely, we propose a ConvNet model for detecting sources of image artifacts that achieves a classifier
    Language English
    Publishing date 2023-02-27
    Publishing country United States
    Document type Journal Article
    ISSN 2640-3498
    ISSN (online) 2640-3498
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Book ; Online ; E-Book: The lake charr salvelinus namaycush

    Hansen, Michael J.

    biology, ecology, distribution, and management

    (Fish & Fisheries Series ; 39)

    2021  

    Abstract: ... in previously glaciated regions of northern continental U.S., Alaska, and Canada that often support important ...

    Author's details edited by Michael J. Hansen, 3 others
    Series title Fish & Fisheries Series ; 39
    Abstract The lake charr Salvelinus namaycush is a ubiquitous member of cold-water lake ecosystems in previously glaciated regions of northern continental U.S., Alaska, and Canada that often support important commercial, recreational, and subsistence fisheries. The lake charr differs from other charrs by its large size, longevity, iteroparity, top-predator specialization, reduced sexual dimorphism, prevalence of lacustrine spawning, and use of deepwater habitat. The species is remarkably variable in phenotype, physiology, and life history, some of which is reflected in its ecology and genetics, with as many as four morphs or ecotypes co-occurring in a single lake. The lake charr is often the top predator in these systems, but is highly adaptable trophically, and is frequently planktivorous in small lakes. The lake charr by their name highlights their common habitat, lakes both large and small, but often frequents rivers and occasionally moves into the Arctic Ocean. Movement and behaviour of lake charr are motivated by access to cool, well-oxygenated water, foraging opportunities, predator avoidance, and reproduction. Owing to their broad distribution and trophic level, the lake charr serves as a sentinel of anthropogenic change. This volume will provide an up-to-date summary of what is currently known about lake charr from distribution to genetics to physiology to ecology. The book provides a compilation and synthesis of available information on the lake charr, beginning with an updated distribution and a revised treatment of the paleoecology of the species. Understanding of ecological and genetic diversity and movement and behaviour of the species has advanced remarkably since the last major synthesis on the species over 40 years ago. Mid-sections of the book provide detailed accounts of the biology and life history of the species, and later sections are devoted to threats to conservation and fishery management practices used to ensure sustainability. A new standard lake charr-specific terminology is also presented. The book will be a valuable reference text for biologists around the world, ecologists, and fishery managers, and of interest to the angling public.
    Keywords Aquatic ecology ; Biotic communities ; Truites (Peixos) ; Ecologia aquàtica ; Biocenosis
    Subject code 577.6
    Language English
    Size 1 online resource (XXXVII, 497 p. 107 illus., 71 illus. in color.)
    Edition 1st ed. 2021.
    Publisher Springer
    Publishing place Cham, Switzerland
    Document type Book ; Online ; E-Book
    Remark Zugriff für angemeldete ZB MED-Nutzerinnen und -Nutzer
    ISBN 3-030-62259-2 ; 3-030-62258-4 ; 978-3-030-62259-6 ; 978-3-030-62258-9
    DOI 10.1007/978-3-030-62259-6
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  5. Article: Evaluating injuries and illnesses that occurred during the Yukon Quest International sled dog race, 2018-2020.

    Hattendorf, Jenna C / Davis, Michael S / Hansen, Cristina M

    Frontiers in veterinary science

    2024  Volume 11, Page(s) 1356061

    Abstract: Introduction: The purpose of this study was to evaluate medical record data from the 2018-2020 Yukon Quest International Sled Dog race to examine injury patterns and risk factors for dogs competing in multi-day ultra-endurance events. Specifically, we ... ...

    Abstract Introduction: The purpose of this study was to evaluate medical record data from the 2018-2020 Yukon Quest International Sled Dog race to examine injury patterns and risk factors for dogs competing in multi-day ultra-endurance events. Specifically, we summarized injuries and illnesses that resulted in canine athletes being removed ("dropped") from competition, and in orthopedic injuries diagnosed in both dropped and finished dogs.
    Methods: The records of 989 dogs that started the race were examined, but only records from dogs in teams that went on to finish the race were included, for a total of 711 records.
    Results and discussion: Three hundred and sixty five dogs (51.3%) were noted to have at least one abnormal finding in their veterinary medical record during the race. Orthopedic injuries were most common, and 291 injuries were ultimately diagnosed in 234 dogs (32.9%). Ultimately, 206 dogs (29%) were dropped from competition, for any reason. The most common reasons for dropping dogs were orthopedic injuries (156 dogs; 188 injuries), gastrointestinal illness (22 dogs), and cardiorespiratory disease (7 dogs). Most orthopedic injuries in dropped dogs occurred in the thoracic limb (
    Language English
    Publishing date 2024-02-27
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2834243-4
    ISSN 2297-1769
    ISSN 2297-1769
    DOI 10.3389/fvets.2024.1356061
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Giant Cell Arteritis Confirmed by 2-[

    Brittain, Jane M / Hansen, Michael S / Hamann, Steffen

    Ophthalmology

    2023  Volume 131, Issue 3, Page(s) 392

    MeSH term(s) Humans ; Giant Cell Arteritis/diagnostic imaging ; Fluorodeoxyglucose F18 ; Positron Emission Tomography Computed Tomography ; Biopsy
    Chemical Substances Fluorodeoxyglucose F18 (0Z5B2CJX4D)
    Language English
    Publishing date 2023-06-26
    Publishing country United States
    Document type Journal Article
    ZDB-ID 392083-5
    ISSN 1549-4713 ; 0161-6420
    ISSN (online) 1549-4713
    ISSN 0161-6420
    DOI 10.1016/j.ophtha.2023.05.031
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Book ; Online: A Path Towards Clinical Adaptation of Accelerated MRI

    Yao, Michael S. / Hansen, Michael S.

    2022  

    Abstract: Accelerated MRI reconstructs images of clinical anatomies from sparsely sampled signal data to reduce patient scan times. While recent works have leveraged deep learning to accomplish this task, such approaches have often only been explored in simulated ... ...

    Abstract Accelerated MRI reconstructs images of clinical anatomies from sparsely sampled signal data to reduce patient scan times. While recent works have leveraged deep learning to accomplish this task, such approaches have often only been explored in simulated environments where there is no signal corruption or resource limitations. In this work, we explore augmentations to neural network MRI image reconstructors to enhance their clinical relevancy. Namely, we propose a ConvNet model for detecting sources of image artifacts that achieves a classifier $F_2$ score of 79.1%. We also demonstrate that training reconstructors on MR signal data with variable acceleration factors can improve their average performance during a clinical patient scan by up to 2%. We offer a loss function to overcome catastrophic forgetting when models learn to reconstruct MR images of multiple anatomies and orientations. Finally, we propose a method for using simulated phantom data to pre-train reconstructors in situations with limited clinically acquired datasets and compute capabilities. Our results provide a potential path forward for clinical adaptation of accelerated MRI.

    Comment: Accepted to ML4H 2022
    Keywords Electrical Engineering and Systems Science - Image and Video Processing ; Computer Science - Computer Vision and Pattern Recognition ; Computer Science - Machine Learning
    Subject code 006
    Publishing date 2022-08-26
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Repeatability of deuterium metabolic imaging of healthy volunteers at 3 T.

    Bøgh, Nikolaj / Vaeggemose, Michael / Schulte, Rolf F / Hansen, Esben S S / Laustsen, Christoffer

    European radiology experimental

    2024  Volume 8, Issue 1, Page(s) 44

    Abstract: Background: Magnetic resonance (MR) imaging of deuterated glucose, termed deuterium metabolic imaging (DMI), is emerging as a biomarker of pathway-specific glucose metabolism in tumors. DMI is being studied as a useful marker of treatment response in a ... ...

    Abstract Background: Magnetic resonance (MR) imaging of deuterated glucose, termed deuterium metabolic imaging (DMI), is emerging as a biomarker of pathway-specific glucose metabolism in tumors. DMI is being studied as a useful marker of treatment response in a scan-rescan scenario. This study aims to evaluate the repeatability of brain DMI.
    Methods: A repeatability study was performed in healthy volunteers from December 2022 to March 2023. The participants consumed 75 g of [6,6'-
    Results: Six male participants were recruited, aged 34 ± 6.5 years (mean ± standard deviation). There was 42 ± 2.7 days between sessions. Whole-brain levels of glutamine + glutamate, lactate, and glucose increased to 3.22 ± 0.4 mM, 1.55 ± 0.3 mM, and 3 ± 0.7 mM, respectively. The best signal-to-noise ratio and repeatability was obtained at the 120-min timepoint. Here, the within-subject whole-brain CoVs were -10% for all metabolites, while the between-subject CoVs were -20%.
    Conclusions: DMI of glucose and its downstream metabolites is feasible and repeatable on a clinical 3 T system.
    Trial registration: ClinicalTrials.gov, NCT05402566 , registered the 25th of May 2022.
    Relevance statement: Brain deuterium metabolic imaging of healthy volunteers is repeatable and feasible at clinical field strengths, enabling the study of shifts in tumor metabolism associated with treatment response.
    Key points: • Deuterium metabolic imaging is an emerging tumor biomarker with unknown repeatability.  • The repeatability of deuterium metabolic imaging is on par with FDG-PET.  • The study of deuterium metabolic imaging in clinical populations is feasible.
    MeSH term(s) Humans ; Male ; Deuterium ; Glucose/metabolism ; Glutamates ; Glutamine ; Healthy Volunteers ; Lactates ; Adult
    Chemical Substances Deuterium (AR09D82C7G) ; Glucose (IY9XDZ35W2) ; Glutamates ; Glutamine (0RH81L854J) ; Lactates
    Language English
    Publishing date 2024-03-13
    Publishing country England
    Document type Clinical Study ; Journal Article
    ISSN 2509-9280
    ISSN (online) 2509-9280
    DOI 10.1186/s41747-024-00426-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: A systematic analysis of regression models for protein engineering.

    Michael, Richard / Kæstel-Hansen, Jacob / Mørch Groth, Peter / Bartels, Simon / Salomon, Jesper / Tian, Pengfei / Hatzakis, Nikos S / Boomsma, Wouter

    PLoS computational biology

    2024  Volume 20, Issue 5, Page(s) e1012061

    Abstract: To optimize proteins for particular traits holds great promise for industrial and pharmaceutical purposes. Machine Learning is increasingly applied in this field to predict properties of proteins, thereby guiding the experimental optimization process. A ... ...

    Abstract To optimize proteins for particular traits holds great promise for industrial and pharmaceutical purposes. Machine Learning is increasingly applied in this field to predict properties of proteins, thereby guiding the experimental optimization process. A natural question is: How much progress are we making with such predictions, and how important is the choice of regressor and representation? In this paper, we demonstrate that different assessment criteria for regressor performance can lead to dramatically different conclusions, depending on the choice of metric, and how one defines generalization. We highlight the fundamental issues of sample bias in typical regression scenarios and how this can lead to misleading conclusions about regressor performance. Finally, we make the case for the importance of calibrated uncertainty in this domain.
    Language English
    Publishing date 2024-05-03
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2193340-6
    ISSN 1553-7358 ; 1553-734X
    ISSN (online) 1553-7358
    ISSN 1553-734X
    DOI 10.1371/journal.pcbi.1012061
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Informal Family Care Partner Well-Being Is Diminished in End-Stage Liver Disease.

    Hansen, Lissi / Chang, Michael F / Hiatt, Shirin / Dieckmann, Nathan F / Lee, Christopher S

    Nursing research

    2024  

    Abstract: Background: Chronic liver disease is a significant global neglected public health problem. End-stage liver disease is associated with substantial symptom complexity, disability, and care needs that require assistance from informal family care partners. ... ...

    Abstract Background: Chronic liver disease is a significant global neglected public health problem. End-stage liver disease is associated with substantial symptom complexity, disability, and care needs that require assistance from informal family care partners. Research on these care partners' caregiver burden or strain, symptoms, and quality of life is sparse and has not focused on these variables as co-occurring or in the context of the quality of the relationship care partners have with the patients.
    Objectives: The purpose of this study was to provide a collective presentation of patterns and determinants of well-being as measured by caregiver strain, depression, sleep, and quality of life in a cohort of informal family care partners for adult outpatients with end-stage liver disease.
    Methods: Care partners (age > 18 years) were recruited from two liver clinics within two tertiary health care systems and invited to complete a cross-sectional survey. They completed the Multidimensional Caregiver Strain Index, Patient Health Questionnaire, Pittsburgh Sleep Quality Index, Short Form Health Survey, and Mutuality Scale. Descriptive statistics and latent class mixture modeling were used to analyze these data.
    Results: The sample was predominantly female and White. The well-being of care partners was diminished. Three distinct classes of well-being were identified: mildly diminished (53.2%), moderately diminished (39.0%), and severely diminished (7.8%). Those at greater risk of worse well-being were younger, spouses, and had poorer relationship quality with the patients.
    Discussion: To improve the well-being of care partners in moderately and severely diminished classes, assessing and addressing caregiver strain and co-occurring symptoms is essential. Addressing this strain and symptoms has the potential to maintain or optimize care partners' ability to provide care to patients. Future researchers should include longitudinal and dyadic studies to examine how patients' disease progression and symptoms may affect family care partners well-being and vice versa.
    Language English
    Publishing date 2024-03-25
    Publishing country United States
    Document type Journal Article
    ZDB-ID 80332-7
    ISSN 1538-9847 ; 0029-6562
    ISSN (online) 1538-9847
    ISSN 0029-6562
    DOI 10.1097/NNR.0000000000000740
    Database MEDical Literature Analysis and Retrieval System OnLINE

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