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https://www.readbyqxmd.com/read/28529251/image-quality-and-clinical-usefulness-of-ray-summation-image-reconstructed-from-ct-data-compared-with-digital-radiography
#1
Shogo Suzuki, Katsuhiro Ichikawa, Shigeru Tamaki
Ray-summation (raysum) images reconstructed from computed tomography (CT) volume data resemble digital radiography (DR) images. Therefore, they have a potential to be used instead of DR images.The aim of this study was to compare the physical image quality evaluated by signal-difference-to-noise ratio (SDNR) and clinical usefulness between raysum and DR images. We employed an oval water phantom simulating adult abdomen for image quality measurement. Raysum images were reconstructed from CT volume data using an assumed x-ray quality of 70 keV...
2017: Nihon Hoshasen Gijutsu Gakkai Zasshi
https://www.readbyqxmd.com/read/28522252/optical-quality-of-rotationally-symmetrical-contact-lenses-derived-from-their-power-profiles
#2
Antonio J Del Águila-Carrasco, Daniel Monsálvez-Romín, Eleni Papadatou
PURPOSE: To present a methodology for evaluating the optical quality of rotationally symmetrical contact lenses (CLs) from a single power profile. METHODS: Simulated rotationally symmetrical power profiles corresponding to different CLs designs (monofocal, two-zone center-near bifocal, and four-zone center-distance bifocal) were used to calculate the wavefront error profile by means of numerical integration. Then, each lens wavefront error profile was spun around the center to obtain the lens wavefront error surface...
May 15, 2017: Contact Lens & Anterior Eye: the Journal of the British Contact Lens Association
https://www.readbyqxmd.com/read/28522170/optimization-of-the-alpha-image-reconstruction-an-iterative-ct-image-reconstruction-with-well-defined-image-quality-metrics
#3
Sergej Lebedev, Stefan Sawall, Michael Knaup, Marc Kachelrieß
PURPOSE: Optimization of the AIR-algorithm for improved convergence and performance. METHODS: The AIR method is an iterative algorithm for CT image reconstruction. As a result of its linearity with respect to the basis images, the AIR algorithm possesses well defined, regular image quality metrics, e.g. point spread function (PSF) or modulation transfer function (MTF), unlike other iterative reconstruction algorithms. The AIR algorithm computes weighting images α to blend between a set of basis images that preferably have mutually exclusive properties, e...
May 15, 2017: Zeitschrift Für Medizinische Physik
https://www.readbyqxmd.com/read/28511564/head-and-neck-effective-dose-and-quantitative-assessment-of-image-quality-a-study-to-compare-cone-beam-ct-and-multislice-spiral-ct
#4
Cosimo Nardi, Cinzia Talamonti, Stefania Pallotta, Paola Saletti, Linda Calistri, Cesare Cordopatri, Stefano Colagrande
OBJECTIVES: To evaluate the effective dose and image quality of horizontal Cone Beam CT (CBCT) in comparison with Multislice Spiral CT (MSCT) in head, cervical spine, ear and dental arches scans. METHODS: Head and neck Alderson-Rando phantom equipped with seventy-four thermoluminescence dosimeters was exposed according to five different scans in CBCT and four different scans in MSCT. Spatial and contrast resolution, in terms of Modulation Transfer Function (MTF) and Contrast-to-Noise Ratio (CNR), were measured to obtain a quantitative assessment of image quality...
May 16, 2017: Dento Maxillo Facial Radiology
https://www.readbyqxmd.com/read/28507149/identification-of-xaf1-mt2a-mutual-antagonism-as-a-molecular-switch-in-cell-fate-decisions-under-stressful-conditions
#5
Cheol-Hee Shin, Min-Goo Lee, Jikhyon Han, Seong-In Jeong, Byung-Kyu Ryu, Sung-Gil Chi
XIAP-associated factor 1 (XAF1) is a tumor suppressor that is commonly inactivated in multiple human neoplasms. However, the molecular mechanism underlying its proapoptotic function remains largely undefined. Here, we report that XAF1 induction by heavy metals triggers an apoptotic switch of stress response by destabilizing metallothionein 2A (MT2A). XAF1 directly interacts with MT2A and facilitates its lysosomal degradation, resulting in the elevation of the free intercellular zinc level and subsequent activation of p53 and inactivation of XIAP...
May 15, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28505304/phytoplasma-conserved-phyllogen-proteins-induce-phyllody-across-the-plantae-by-degrading-floral-mads-domain-proteins
#6
Yugo Kitazawa, Nozomu Iwabuchi, Misako Himeno, Momoka Sasano, Hiroaki Koinuma, Takamichi Nijo, Tatsuya Tomomitsu, Tetsuya Yoshida, Yukari Okano, Nobuyuki Yoshikawa, Kensaku Maejima, Kenro Oshima, Shigetou Namba
ABCE-class MADS domain transcription factors (MTFs) are key regulators of floral organ development in angiosperms. Aberrant expression of these genes can result in abnormal floral traits such as phyllody. Phyllogen is a virulence factor conserved in phytoplasmas, plant pathogenic bacteria of the class Mollicutes. It triggers phyllody in Arabidopsis thaliana by inducing degradation of A- and E-class MTFs. However, it is still unknown whether phyllogen can induce phyllody in plants other than A. thaliana, although phytoplasma-associated phyllody symptoms are observed in a broad range of angiosperms...
May 15, 2017: Journal of Experimental Botany
https://www.readbyqxmd.com/read/28474251/hip-fractures-in-young-adults-a-retrospective-cross-sectional-study-of-characteristics-injury-mechanism-risk-factors-complications-and-follow-up
#7
Michael T Wang, Sarah H Yao, Phillip Wong, Anne Trinh, Peter R Ebeling, Ton Tran, Frances Milat, Nora Mutalima
This study characterises risk factors, complications and follow-up of minimal trauma hip fractures in young adults, adding to limited information examining the management framework. This group have severe systemic disease and significant risk of post-operative complications and subsequent fractures. Improved medical referral pathways enable management of osteoporosis and comorbid diseases. AIMS: There is a paucity of literature examining minimal trauma hip fractures in young adults, despite extensive management guidelines for older patients...
December 2017: Archives of Osteoporosis
https://www.readbyqxmd.com/read/28450446/how-question-types-reveal-student-thinking-an-experimental-comparison-of-multiple-true-false-and-free-response-formats
#8
Joanna K Hubbard, Macy A Potts, Brian A Couch
Assessments represent an important component of undergraduate courses because they affect how students interact with course content and gauge student achievement of course objectives. To make decisions on assessment design, instructors must understand the affordances and limitations of available question formats. Here, we use a crossover experimental design to identify differences in how multiple-true-false (MTF) and free-response (FR) exam questions reveal student thinking regarding specific conceptions. We report that correct response rates correlate across the two formats but that a higher percentage of students provide correct responses for MTF questions...
2017: CBE Life Sciences Education
https://www.readbyqxmd.com/read/28444524/in-vitro-optical-quality-of-monofocal-aspheric-toric-intraocular-lenses-effect-of-cylindrical-power
#9
Teresa Ferrer-Blasco, Alberto Domínguez-Vicent, Santiago García-Lázaro, María Amparo Diez, José F Alfonso, José J Esteve-Taboada
PURPOSE: To assess the in vitro optical quality of monofocal aspheric toric intraocular lenses (IOLs) as a function of the cylindrical power. METHODS: The in vitro optical quality of the AcrySof IQ Toric IOLs SN6AT2, SN6AT3, SN6AT4, SN6AT5 and SN6AT6 (Alcon Laboratories Inc., Forth Worth, TX, USA) was assessed with an instrument conceived for measuring Zernike's coefficients at 3.0- and 5.0-mm apertures. As a reference, the aspheric monofocal lens AcrySof IQ Aspheric SN60WF (Alcon Laboratories Inc...
April 25, 2017: International Ophthalmology
https://www.readbyqxmd.com/read/28437735/detective-quantum-efficiency-dqe-in-pet-scanners-a-simulation-study
#10
George E Karpetas, Christos M Michail, George P Fountos, Nektarios I Kalyvas, Ioannis G Valais, Ioannis S Kandarakis, George S Panayiotakis
The aim of the present study is to introduce the detective quantum efficiency (DQE) for the image quality assessment of positron emission tomography (PET) scanners. For this purpose, a thin layer chromatography (TLC) plane source was simulated using a previously validated, scanner and source geometry, Monte Carlo (MC) model. The model was developed with the Geant4 application for tomographic emission (GATE) MC package and reconstructed images obtained with the software for tomographic image reconstruction (STIR), with cluster computing...
April 12, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/28425220/associations-between-the-transsexual-voice-questionnaire-tvq-mtf-and-self-report-of-voice-femininity-and-acoustic-voice-measures
#11
Georgia Dacakis, Jennifer Oates, Jacinta Douglas
BACKGROUND: The Transsexual Voice Questionnaire (TVQ(MtF) ) was designed to capture the voice-related perceptions of individuals whose gender identity as female is the opposite of their birth-assigned gender (MtF women). Evaluation of the psychometric properties of the TVQ(MtF) is ongoing. AIMS: To investigate associations between TVQ(MtF) scores and (1) self-perceptions of voice femininity and (2) acoustic parameters of voice pitch and voice quality in order to evaluate further the validity of the TVQ(MtF) ...
April 19, 2017: International Journal of Language & Communication Disorders
https://www.readbyqxmd.com/read/28421153/breast-cancer-suspicion-in-a-transgender-male-to-female-patient-on-hormone-replacement-therapy-presenting-with-right-breast-mass-breast-cancer-risk-assessment-and-presentation-of-a-rare-lesion
#12
Krystina Tongson, Victoria Konovalova, Naveen Dhawan, Steffi Sharma, Jaya Bahl, Mohammad Masri
There has been an increasing use of hormonal therapy among male-to-female (MtF) transgender individuals. This long-term hormone replacement therapy (HRT) renders MtF individuals a unique patient subgroup in terms of breast cancer risk. This case describes a MtF transgender who presented with a breast lesion concerning for malignancy following hormonal replacement therapy. The patient additionally had a strong family history of breast cancer. Final pathology revealed lobular hyperplasia in the setting of gynecomastia and pseudoangiomatous stromal hyperplasia (PASH)...
2017: Case Reports in Oncological Medicine
https://www.readbyqxmd.com/read/28418775/research-101-an-initiative-to-encourage-and-facilitate-quality-resident-research-in-a-military-setting
#13
Kathryn E Marshall, Tanisha L Hammill
Objective Describe and evaluate a structured research program initiated at a tertiary Department of Defense (DOD) Medical Training Facility (MTF) to encourage and facilitate the conduct of research investigations, specifically among residents and junior or inexperienced investigators, but applicable for all DOD otolaryngology (ENT) and audiology providers. Methods A new comprehensive program was deployed in the ENT clinic at Madigan Army Medical Center (MAMC) to help improve the research program. Identified gaps in research methods and regulatory training were incorporated into the existing graduate medical education program along with structured mentorship between residents and senior staff...
April 1, 2017: Otolaryngology—Head and Neck Surgery
https://www.readbyqxmd.com/read/28407769/geographic-variation-within-the-military-health-system
#14
Linda Kimsey, Samuel Olaiya, Chad Smith, Andrew Hoburg, Stuart R Lipsitz, Tracey Koehlmoos, Louis L Nguyen, Joel S Weissman
BACKGROUND: This study seeks to quantify variation in healthcare utilization and per capita costs using system-defined geographic regions based on enrollee residence within the Military Health System (MHS). METHODS: Data for fiscal years 2007 - 2010 were obtained from the Military Health System under a data sharing agreement with the Defense Health Agency (DHA). DHA manages all aspects of the Department of Defense Military Health System, including TRICARE. Adjusted rates were calculated for per capita costs and for two procedures with high interest to the MHS- back surgery and Cesarean sections for TRICARE Prime and Plus enrollees...
April 13, 2017: BMC Health Services Research
https://www.readbyqxmd.com/read/28406501/culture-dependent-enumeration-methods-failed-to-simultaneously-detect-disinfectant-injured-and-genetically-modified-escherichia-coli-in-drinking-water
#15
Jing Li, Lu Liu, Dong Yang, Wei-Li Liu, Zhi-Qiang Shen, Hong-Mei Qu, Zhi-Gang Qiu, Ai-Ming Hou, Da-Ning Wang, Chen-Shi Ding, Jun-Wen Li, Jian-Hua Guo, Min Jin
Underestimation of Escherichia coli in drinking water, an indicator microorganism of sanitary risk, may result in potential risks of waterborne diseases. However, the detection of disinfectant-injured or genetically modified (GM) E. coli has been largely overlooked so far. To evaluate the accuracy of culture-dependent enumeration with regard to disinfectant-injured and GM E. coli, chlorine- or ozone-injured wild-type (WT) and GM E. coli were prepared and characterized. Then, water samples contaminated with these E...
April 13, 2017: Environmental Science. Processes & Impacts
https://www.readbyqxmd.com/read/28366591/quality-of-life-and-patient-satisfaction-following-male-to-female-sex-reassignment-surgery
#16
Nikolaos A Papadopulos, Jean-Daniel Lellé, Dmitry Zavlin, Peter Herschbach, Gerhard Henrich, Laszlo Kovacs, Benjamin Ehrenberger, Anna-Katharina Kluger, Hans-Guenther Machens, Juergen Schaff
BACKGROUND: Surveys on quality of life (QOL) of male-to-female (MTF) transsexuals have found low QOL scores before and increased satisfaction scores after sex-reassignment surgery (SRS). To our knowledge, many of them lack standardized questionnaires and comparisons with normative data to evaluate different vaginoplasty techniques. AIM: To analyze patient satisfaction and QOL after SRS. METHODS: Forty-seven patients participated in this study...
March 30, 2017: Journal of Sexual Medicine
https://www.readbyqxmd.com/read/28362638/task-driven-optimization-of-ct-tube-current-modulation-and-regularization-in-model-based-iterative-reconstruction
#17
Grace J Gang, Jeffrey H Siewerdsen, J Webster Stayman
Tube current modulation (TCM) is routinely adopted on diagnostic CT scanners for dose reduction. Conventional TCM strategies are generally designed for filtered-backprojection (FBP) reconstruction to satisfy simple image quality requirements based on noise. This work investigates TCM designs for model-based iterative reconstruction (MBIR) to achieve optimal imaging performance as determined by a task-based image quality metric. Additionally, regularization is an important aspect of MBIR that is jointly optimized with TCM, and includes both the regularization strength that controls overall smoothness as well as directional weights that permits control of the isotropy/anisotropy of the local noise and resolution properties...
March 31, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28332875/the-biologic-basis-of-transgender-identity-2d-4d-finger-length-ratios-implicate-a-role-for-prenatal-androgen-activity
#18
Matthew Leinung, Christina Wu
Objective The biologic basis for gender identity is unknown. Research has shown that the ratio of the length of the second and fourth digits (2D:4D) in mammals is influenced by gender in utero, but data on 2D:4D ratios in transgender individuals are scarce and contradictory. We sought an association with 2D:4D ratio and gender identity in our transgender clinic population in Albany, NY. Methods We prospectively recruited 118 transgender subjects undergoing hormonal therapy (50 female to male (FTM) and 68 male to female (MTF) for finger length measurement...
March 23, 2017: Endocrine Practice
https://www.readbyqxmd.com/read/28323803/patient-response-to-an-integrated-orthotic-and-rehabilitation-initiative-for-traumatic-injuries-the-prioriti-mtf-study
#19
Joseph R Hsu, Johnny G Owens, Jennifer DeSanto, John R Fergason, Kevin M Kuhn, Benjamin K Potter, Daniel J Stinner, Robert G Sheu, Sandra L Waggoner, Jason M Wilken, Yanjie Huang, Daniel O Scharfstein, Ellen J MacKenzie
Although limb salvage is now possible for many high-energy open fractures and crush injuries to the distal tibia, ankle, hindfoot, and midfoot, orthotic options are limited. The Intrepid Dynamic Exoskeletal Orthosis (IDEO) is a custom, energy-storing carbon fiber orthosis developed for trauma patients undergoing limb salvage. The IDEO differs from other orthoses in that it allows patients with ankle weakness to have more normal ankle biomechanics and increased ankle power. This article describes the design of a study to evaluate the effectiveness of the IDEO when delivered together with a high-intensity, sports medicine-based approach to rehabilitation...
April 2017: Journal of Orthopaedic Trauma
https://www.readbyqxmd.com/read/28297454/evaluation-of-cassette-based-digital-radiography-detectors-using-standardized-image-quality-metrics-aapm-tg-150-draft-image-detector-tests
#20
Guang Li, Travis C Greene, Thomas K Nishino, Charles E Willis
The purpose of this study was to evaluate several of the standardized image quality metrics proposed by the American Association of Physics in Medicine (AAPM) Task Group 150. The task group suggested region-of-interest (ROI)-based techniques to measure nonuniformity, minimum signal-to-noise ratio (SNR), number of anomalous pixels, and modulation transfer function (MTF). This study evaluated the effects of ROI size and layout on the image metrics by using four different ROI sets, assessed result uncertainty by repeating measurements, and compared results with two commercially available quality control tools, namely the Carestream DIRECTVIEW Total Quality Tool (TQT) and the GE Healthcare Quality Assurance Process (QAP)...
September 2016: Journal of Applied Clinical Medical Physics
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