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  1. Article: Patterns of Restricted and Repetitive Behaviors in Toddlers and Young Children with Autism Spectrum Disorder.

    Song, Da-Yea / Kim, Dabin / Lee, Hannah J / Bong, Guiyoung / Han, Jae Hyun / Yoo, Hee Jeong

    Soa--ch'ongsonyon chongsin uihak = Journal of child & adolescent psychiatry

    2022  Volume 33, Issue 2, Page(s) 35–40

    Abstract: Objectives: Restricted and repetitive behaviors (RRBs) are a core symptom in the diagnosis of autism spectrum disorder (ASD). The complexity of behavioral patterns has called for the creation of phenotypically homogeneous subgroups among individuals ... ...

    Abstract Objectives: Restricted and repetitive behaviors (RRBs) are a core symptom in the diagnosis of autism spectrum disorder (ASD). The complexity of behavioral patterns has called for the creation of phenotypically homogeneous subgroups among individuals with ASD. The purpose of this study was 1) to investigate the different types of RRBs and 2) to explore whether subgroups created by RRBs would show unique levels of functioning in toddlers and young children with ASD.
    Methods: A total of 313 children with ASD, aged 12-42 months were included in the analysis. The Autism Diagnostic Interview-Revised was used to obtain information on the different types of RRBs by grouping 15 items into six categories. The Vineland Adaptive Behaviors Scale, a parent-reported questionnaire, was used to measure adaptive functioning. A portion of the children were analyzed separately for verbal-related RRBs based on their expressive language level. Two-step cluster analysis using RRB groups as features was used to create subgroups. Analysis of covariance while covarying for age and language was performed to explore the clinical characteristics of each cluster group.
    Results: Sensory-related RRBs were the most prevalent, followed by circumscribed interests, interest in objects, resistance to change, and repetitive body movements. A subset of the children was analyzed separately to explore verbal-related RRBs. Four cluster groups were created based on reported RRBs, with multiple RRBs demonstrating significant delays in adaptive functioning.
    Conclusion: Heterogeneity of RRBs emerges at a young age. The different patterns of RRBs can be used as valuable information to determine developmental trajectories with better implications for treatment approaches.
    Language English
    Publishing date 2022-01-01
    Publishing country Korea (South)
    Document type Journal Article
    ZDB-ID 3035377-4
    ISSN 2233-9183 ; 1225-729X
    ISSN (online) 2233-9183
    ISSN 1225-729X
    DOI 10.5765/jkacap.220001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Low-density gel dosimeter for measurement of the electron return effect in an MR-linac.

    McDonald, Brigid A / Lee, Hannah J / Ibbott, Geoffrey S

    Physics in medicine and biology

    2019  Volume 64, Issue 20, Page(s) 205016

    Abstract: Radiation therapy in the presence of a strong magnetic field is known to cause regions of enhanced and reduced dose at interfaces of materials with varying densities, in a phenomenon known as the electron return effect (ERE). In this study, a novel low- ... ...

    Abstract Radiation therapy in the presence of a strong magnetic field is known to cause regions of enhanced and reduced dose at interfaces of materials with varying densities, in a phenomenon known as the electron return effect (ERE). In this study, a novel low-density gel dosimeter was developed to simulate lung tissue and was used to measure the ERE at the lung-soft tissue interface. Low-density gel dosimeters were developed with Fricke xylenol orange gelatin (FXG) and ferrous oxide xylenol orange (FOX) gels mixed with polystyrene foam beads of various sizes. The gels were characterized based on CT number, MR signal intensity, and uniformity. All low-density gels had CT numbers roughly equivalent to lung tissue. The optimal lung-equivalent gel formulation was determined to be FXG with  <1 mm polystyrene beads due to the higher signal intensity of FXG compared to FOX and the higher uniformity with the small beads. Dose response curves were generated for the optimal low-density gel and conventional FXG. The change in spin-lattice relaxation rate (R1) before and after irradiation was linear with dose for both gels. Next, phantoms consisting of concentric cylinders with low-density and conventional FXG were created to simulate the lung-soft tissue interface. The phantoms were irradiated in a conventional linear accelerator (linac) and in a linac combined with a 1.5 T magnetic resonance imaging (MRI) unit (MR-linac) to measure the effects of the magnetic field on the dose distribution. Hot and cold spots were observed in the dose distribution at the boundaries between the gels for the phantom irradiated in the MR-linac but not the conventional linac, consistent with the ERE.
    MeSH term(s) Electrons ; Ferrous Compounds/chemistry ; Gels/chemistry ; Gels/radiation effects ; Humans ; Lung/diagnostic imaging ; Magnetic Resonance Imaging/methods ; Particle Accelerators ; Phantoms, Imaging ; Phenols/chemistry ; Radiation Dosimeters/standards ; Radiometry/methods ; Radiotherapy/instrumentation ; Radiotherapy/methods ; Radiotherapy Planning, Computer-Assisted/instrumentation ; Radiotherapy Planning, Computer-Assisted/methods ; Sulfoxides/chemistry
    Chemical Substances Ferrous Compounds ; Gels ; Phenols ; Sulfoxides ; ferrous oxide (G7036X8B5H) ; xylenol orange (S2VDY878QD)
    Language English
    Publishing date 2019-10-16
    Publishing country England
    Document type Journal Article
    ZDB-ID 208857-5
    ISSN 1361-6560 ; 0031-9155
    ISSN (online) 1361-6560
    ISSN 0031-9155
    DOI 10.1088/1361-6560/ab4321
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  3. Article ; Online: AAPM Task Group 334: A guidance document to using radiotherapy immobilization devices and accessories in an MR environment.

    Hobson, Maritza A / Hu, Yanle / Caldwell, Barrett / Cohen, Gil'ad N / Glide-Hurst, Carri / Huang, Long / Jackson, Paul D / Jang, Sunyoung / Langner, Ulrich / Lee, Hannah J / Levesque, Ives R / Narayanan, Sreeram / Park, Justin C / Steffen, John / Wu, Q Jackie / Zhou, Yong

    Medical physics

    2024  

    Abstract: Use of magnetic resonance (MR) imaging in radiation therapy has increased substantially in recent years as more radiotherapy centers are having MR simulators installed, requesting more time on clinical diagnostic MR systems, or even treating with ... ...

    Abstract Use of magnetic resonance (MR) imaging in radiation therapy has increased substantially in recent years as more radiotherapy centers are having MR simulators installed, requesting more time on clinical diagnostic MR systems, or even treating with combination MR linear accelerator (MR-linac) systems. With this increased use, to ensure the most accurate integration of images into radiotherapy (RT), RT immobilization devices and accessories must be able to be used safely in the MR environment and produce minimal perturbations. The determination of the safety profile and considerations often falls to the medical physicist or other support staff members who at a minimum should be a Level 2 personnel as per the ACR. The purpose of this guidance document will be to help guide the user in making determinations on MR Safety labeling (i.e., MR Safe, Conditional, or Unsafe) including standard testing, and verification of image quality, when using RT immobilization devices and accessories in an MR environment.
    Language English
    Publishing date 2024-04-22
    Publishing country United States
    Document type Journal Article
    ZDB-ID 188780-4
    ISSN 2473-4209 ; 0094-2405
    ISSN (online) 2473-4209
    ISSN 0094-2405
    DOI 10.1002/mp.17061
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Real-time volumetric relative dosimetry for magnetic resonance-image-guided radiation therapy (MR-IGRT).

    Lee, Hannah J / Kadbi, Mo / Bosco, Gary / Ibbott, Geoffrey S

    Physics in medicine and biology

    2018  Volume 63, Issue 4, Page(s) 45021

    Abstract: The integration of magnetic resonance imaging (MRI) with linear accelerators (linac) has enabled the use of 3D MR-visible gel dosimeters for real-time verification of volumetric dose distributions. Several iron-based radiochromic 3D gels were created in- ... ...

    Abstract The integration of magnetic resonance imaging (MRI) with linear accelerators (linac) has enabled the use of 3D MR-visible gel dosimeters for real-time verification of volumetric dose distributions. Several iron-based radiochromic 3D gels were created in-house then imaged and irradiated in a pre-clinical 1.5 T-7 MV MR-Linac. MR images were acquired using a range of balanced-fast field echo (b-FFE) sequences during irradiation to assess the contrast and dose response in irradiated regions and to minimize the presence of MR artifacts. Out of four radiochromic 3D gel formulations, the FOX 3D gel was found to provide superior MR contrast in the irradiated regions. The FOX gels responded linearly with respect to real-time dose and the signal remained stable post-irradiation for at least 20 min. The response of the FOX gel also was found to be unaffected by the radiofrequency and gradient fields created by the b-FFE sequence during irradiation. A reusable version of the FOX gel was used for b-FFE sequence optimization to reduce artifacts by increasing the number of averages at the expense of temporal resolution. Regardless of the real-time MR sequence used, the FOX 3D gels responded linearly to dose with minimal magnetic field effects due to the strong 1.5 T field or gradient fields present during imaging. These gels can easily be made in-house using non-reusable and reusable formulations depending on the needs of the clinic, and the results of this study encourage further applications of 3D gels for MR-IGRT applications.
    MeSH term(s) Humans ; Magnetic Resonance Imaging/instrumentation ; Magnetic Resonance Imaging/methods ; Particle Accelerators ; Radiation Dosimeters ; Radiometry/methods ; Radiotherapy Dosage ; Radiotherapy, Image-Guided/instrumentation ; Radiotherapy, Image-Guided/methods
    Language English
    Publishing date 2018-02-20
    Publishing country England
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 208857-5
    ISSN 1361-6560 ; 0031-9155
    ISSN (online) 1361-6560
    ISSN 0031-9155
    DOI 10.1088/1361-6560/aaac22
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Iron-based radiochromic systems for UV dosimetry applications.

    Lee, Hannah J / Alqathami, Mamdooh / Blencowe, Anton / Ibbott, Geoffrey

    Physics in medicine and biology

    2018  Volume 63, Issue 2, Page(s) 25010

    Abstract: Phototherapy treatment using ultraviolet (UV) A and B light sources has long existed as a treatment option for various skin conditions. Quality control for phototherapy treatment recommended by the British Association of Dermatologists and British ... ...

    Abstract Phototherapy treatment using ultraviolet (UV) A and B light sources has long existed as a treatment option for various skin conditions. Quality control for phototherapy treatment recommended by the British Association of Dermatologists and British Photodermatology Group generally focused on instrumentation-based dosimetry measurements. The purpose of this study was to present an alternative, easily prepared dosimeter system for the measurement of UV dose and as a simple quality assurance technique for phototherapy treatments. Five different UVA-sensitive radiochromic dosimeter formulations were investigated and responded with a measurable and visible optical change both in solution and in gel form. Iron(III) reduction reaction formulations were found to be more sensitive to UVA compared to iron(II) oxidation formulations. One iron(III) reduction formulation was found to be especially promising due to its sensitivity to UVA dose, ease of production, and linear response up to a saturation point.
    MeSH term(s) Dose-Response Relationship, Radiation ; Film Dosimetry/instrumentation ; Film Dosimetry/methods ; Gels/chemistry ; Humans ; Image Processing, Computer-Assisted ; Iron/chemistry ; Phototherapy ; Ultraviolet Rays
    Chemical Substances Gels ; Iron (E1UOL152H7)
    Language English
    Publishing date 2018-01-09
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 208857-5
    ISSN 1361-6560 ; 0031-9155
    ISSN (online) 1361-6560
    ISSN 0031-9155
    DOI 10.1088/1361-6560/aa9a64
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Simultaneous motion monitoring and truth-in-delivery analysis imaging framework for MR-guided radiotherapy.

    Mickevicius, Nikolai J / Chen, Xinfeng / Boyd, Zachary / Lee, Hannah J / Ibbott, Geoffrey S / Paulson, Eric S

    Physics in medicine and biology

    2018  Volume 63, Issue 23, Page(s) 235014

    Abstract: Intrafraction motion (i.e. motion occurring during a treatment session) can play a pivotal role in the success of abdominal and thoracic radiation therapy. Hybrid magnetic resonance-guided radiotherapy (MR-gRT) systems have the potential to control for ... ...

    Abstract Intrafraction motion (i.e. motion occurring during a treatment session) can play a pivotal role in the success of abdominal and thoracic radiation therapy. Hybrid magnetic resonance-guided radiotherapy (MR-gRT) systems have the potential to control for intrafraction motion. Recently, we introduced an MRI sequence capable of acquiring real-time cine imaging in two orthogonal planes (SOPI). We extend SOPI here to permit dynamic updating of slice positions in one-plane while keeping the other plane position fixed. In this implementation, cine images from the static plane are used for motion monitoring and as image navigators to sort stepped images in the other plane, producing dynamic 4D image volumes for use in dose reconstruction. A custom 3D-printed target, designed to mimic the pancreas and duodenum and filled with radiochromic FXG gel, was interfaced to the dynamic motion phantom. 4D-SOPI was acquired in a dynamic motion phantom driven by an actual patient respiratory waveform displaying amplitude/frequency variations and drifting and in a healthy volunteer. Unique 4D-MRI epochs were reconstructed from a time series of phantom motion. Dose from a static 4 cm  ×  15 cm field was calculated on each 4D respiratory phase bin and epoch image, scaled by the time spent in each bin, and then rigidly accumulated. The phantom was then positioned on an Elekta MR-Linac and irradiated while moving. Following irradiation, actual dose deposited to the FXG gel was determined by applying a R
    MeSH term(s) Algorithms ; Calibration ; Healthy Volunteers ; Humans ; Image Processing, Computer-Assisted ; Imaging, Three-Dimensional/methods ; Magnetic Resonance Imaging ; Motion ; Phantoms, Imaging ; Radiotherapy, Image-Guided/methods ; Reproducibility of Results ; Respiration ; X-Ray Film
    Language English
    Publishing date 2018-11-26
    Publishing country England
    Document type Journal Article
    ZDB-ID 208857-5
    ISSN 1361-6560 ; 0031-9155
    ISSN (online) 1361-6560
    ISSN 0031-9155
    DOI 10.1088/1361-6560/aaec91
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  7. Article ; Online: Obesity-associated biomarkers and executive function in children.

    Miller, Alison L / Lee, Hannah J / Lumeng, Julie C

    Pediatric research

    2014  Volume 77, Issue 1-2, Page(s) 143–147

    Abstract: There is a growing focus on links between obesity and cognitive decline in adulthood, including Alzheimer's disease. It is also increasingly recognized that obesity in youth is associated with poorer cognitive function, specifically executive functioning ...

    Abstract There is a growing focus on links between obesity and cognitive decline in adulthood, including Alzheimer's disease. It is also increasingly recognized that obesity in youth is associated with poorer cognitive function, specifically executive functioning skills such as inhibitory control and working memory, which are critical for academic achievement. Emerging literature provides evidence for possible biological mechanisms driven by obesity; obesity-associated biomarkers such as adipokines, obesity-associated inflammatory cytokines, and obesity-associated gut hormones have been associated with learning, memory, and general cognitive function. To date, examination of obesity-associated biology with brain function has primarily occurred in animal models. The few studies examining such biologically mediated pathways in adult humans have corroborated the animal data, but this body of work has gone relatively unrecognized by the pediatric literature. Despite the fact that differences in these biomarkers have been found in association with obesity in children, the possibility that obesity-related biology could affect brain development in children has not been actively considered. We review obesity-associated biomarkers that have shown associations with neurocognitive skills, specifically executive functioning skills, which have far-reaching implications for child development. Understanding such gut-brain associations early in the lifespan may yield unique intervention implications.
    MeSH term(s) Adipokines/metabolism ; Biomarkers/metabolism ; Brain/growth & development ; Brain/metabolism ; Child ; Child Development/physiology ; Cytokines/metabolism ; Executive Function/physiology ; Humans ; Leptin/metabolism ; Obesity/metabolism
    Chemical Substances Adipokines ; Biomarkers ; Cytokines ; Leptin
    Language English
    Publishing date 2014-10-13
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Review
    ZDB-ID 4411-8
    ISSN 1530-0447 ; 0031-3998
    ISSN (online) 1530-0447
    ISSN 0031-3998
    DOI 10.1038/pr.2014.158
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  8. Article ; Online: Investigation of magnetic field effects on the dose-response of 3D dosimeters for magnetic resonance - image guided radiation therapy applications.

    Lee, Hannah J / Roed, Yvonne / Venkataraman, Sara / Carroll, Mitchell / Ibbott, Geoffrey S

    Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology

    2017  Volume 125, Issue 3, Page(s) 426–432

    Abstract: Background and purpose: The strong magnetic field of integrated magnetic resonance imaging (MRI) and radiation treatment systems influences secondary electrons resulting in changes in dose deposition in three dimensions. To fill the need for volumetric ... ...

    Abstract Background and purpose: The strong magnetic field of integrated magnetic resonance imaging (MRI) and radiation treatment systems influences secondary electrons resulting in changes in dose deposition in three dimensions. To fill the need for volumetric dose quality assurance, we investigated the effects of strong magnetic fields on 3D dosimeters for MR-image-guided radiation therapy (MR-IGRT) applications.
    Material and methods: There are currently three main categories of 3D dosimeters, and the following were used in this study: radiochromic plastic (PRESAGE®), radiochromic gel (FOX), and polymer gel (BANG™). For the purposes of batch consistency, an electromagnet was used for same-day irradiations with and without a strong magnetic field (B
    Results: For PRESAGE®, the percent difference in optical signal with and without B
    Conclusions: The percent differences in responses with and without strong magnetic fields were minimal for all three 3D dosimeter systems. These 3D dosimeters therefore can be applied to MR-IGRT without requiring a correction factor.
    MeSH term(s) Dose-Response Relationship, Radiation ; Humans ; Magnetic Fields ; Magnetic Resonance Imaging/methods ; Radiation Dosimeters ; Radiotherapy, Image-Guided/methods
    Language English
    Publishing date 2017
    Publishing country Ireland
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 605646-5
    ISSN 1879-0887 ; 0167-8140
    ISSN (online) 1879-0887
    ISSN 0167-8140
    DOI 10.1016/j.radonc.2017.08.027
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  9. Article ; Online: Low-income women's conceptualizations of emotional- and stress-eating.

    Hayman, Lenwood W / Lee, Hannah J / Miller, Alison L / Lumeng, Julie C

    Appetite

    2014  Volume 83, Page(s) 269–276

    Abstract: Emotional- and stress-eating have been proposed as risk factors for obesity. However, the way that individuals conceptualize these behaviors is not well understood and no studies have employed a qualitative approach. We sought to understand how women ... ...

    Abstract Emotional- and stress-eating have been proposed as risk factors for obesity. However, the way that individuals conceptualize these behaviors is not well understood and no studies have employed a qualitative approach. We sought to understand how women conceptualize emotional- and stress-eating. Sixty-one low-income women from South-central Michigan with young children (ages 2-5 years) participated in either a focus group or individual semi-structured interview during which they were asked about their conceptualizations of eating behaviors among adults and children. Responses were transcribed and the constant comparative method was used to identify themes. Identified themes included that emotional- and stress-eating are viewed as uncommon, severe, pitiable behaviors that reflect a lack of self-control and are highly stigmatized; that when these behaviors occurred among children, the behaviors resulted from neglect or even abuse; and that bored-eating is viewed as distinct from emotional- or stress-eating and is a common and humorous behavior with which participants readily self-identified. Future research and interventions should seek to develop more detailed conceptualizations of these behaviors to improve measurement, destigmatize emotional- and stress-eating and potentially capitalize on the strong identification with bored-eating by targeting this behavior for interventions.
    MeSH term(s) Adolescent ; Adult ; Boredom ; Child Abuse/psychology ; Community Health Centers ; Feeding and Eating Disorders/etiology ; Feeding and Eating Disorders/physiopathology ; Feeding and Eating Disorders/psychology ; Feeding and Eating Disorders of Childhood/etiology ; Feeding and Eating Disorders of Childhood/physiopathology ; Feeding and Eating Disorders of Childhood/psychology ; Female ; Focus Groups ; Health Knowledge, Attitudes, Practice ; Humans ; Maternal Behavior ; Michigan ; Middle Aged ; Models, Psychological ; Poverty ; Severity of Illness Index ; Social Stigma ; Spouse Abuse/psychology ; Stress, Physiological ; Stress, Psychological/etiology ; Stress, Psychological/physiopathology ; Young Adult
    Language English
    Publishing date 2014-09-11
    Publishing country England
    Document type Journal Article ; Multicenter Study ; Research Support, N.I.H., Extramural
    ZDB-ID 1461347-5
    ISSN 1095-8304 ; 0195-6663
    ISSN (online) 1095-8304
    ISSN 0195-6663
    DOI 10.1016/j.appet.2014.09.005
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  10. Article: Simulated Clinical Skills for Veterinary Students Supplement Limited Animal and Clinical Resources in Developing Countries.

    Seddon, Jennifer M / Vo, An Thi Tra / Kempster, Samantha R / Lee, Hannah J / Nguyen, Toan Tat / Munce, Katherine / Bianco, Alexander Del / Chakitdee, Vithaya / Quang, Thong / Shapter, Frances M

    Journal of veterinary medical education

    2020  Volume 47, Issue s1, Page(s) 92–98

    Abstract: As part of an OIE Veterinary Education Twinning Project linking The University of Queensland, Australia and Nong Lam University, Vietnam, the limited access to animal and clinical resources was identified as an impediment to high quality veterinary ... ...

    Abstract As part of an OIE Veterinary Education Twinning Project linking The University of Queensland, Australia and Nong Lam University, Vietnam, the limited access to animal and clinical resources was identified as an impediment to high quality veterinary education at Nong Lam University. However, student focused, simulated learning spaces, which have been widely adopted in veterinary training, are a cost-effective opportunity to provide initial clinical skills to students in countries where resourcing is constrained. In clinical skills training facilities, students use models and simulators to practice their clinical skills to develop the confidence, competence and muscle memory to enter the clinical phase of their training. While high-fidelity veterinary simulators and models are expensive, effective models for foundational clinical skills development can be built in-house for students to practice their skills authentically. This article outlines the cost effective establishment of a veterinary clinical skills training facility at Nong Lam University.
    MeSH term(s) Animals ; Australia ; Clinical Competence ; Developing Countries ; Education, Veterinary ; Humans ; Students
    Language English
    Publishing date 2020-11-18
    Publishing country Canada
    Document type Journal Article
    ISSN 0748-321X
    ISSN 0748-321X
    DOI 10.3138/jvme-2019-0112
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