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https://www.readbyqxmd.com/read/28641936/combined-vaginoplasty-technique-for-male-to-female-sex-reassignment-surgery-operative-approach-and-outcomes
#1
Nikolaos A Papadopulos, Dmitry Zavlin, Jean-Daniel Lellé, Peter Herschbach, Gerhard Henrich, Laszlo Kovacs, Benjamin Ehrenberger, Hans-Guenther Machens, Juergen Schaff
BACKGROUND: Several therapy options exist for male-to-female (MTF) transgenders desiring sex reassignment. Surgery includes numerous different procedures. Of those, vaginoplasty is predominant and aims at providing attractive esthetics and fully functional genitals. This study aimed to present the surgical results of our modified combined vaginoplasty technique in a consecutive patient cohort. METHODS: We included 40 MTF transgender patients who underwent a two-stage sex reassignment surgery (SRS) in an observational prospective study between September 2012 and January 2014...
May 27, 2017: Journal of Plastic, Reconstructive & Aesthetic Surgery: JPRAS
https://www.readbyqxmd.com/read/28636792/mtf-and-dqe-enhancement-using-an-apodized-aperture-x-ray-detector-design
#2
Tomi F Nano, Terenz Escartin, Elina Ismailova, Karim S Karim, Jan Lindstrȍm, Ho Kyung Kim, Ian A Cunningham
PURPOSE: Acquisition of high-quality x-ray images using low patient exposures requires detectors with high detective quantum efficiency (DQE). We describe a novel apodized-aperture pixel (AAP) design that increases high-frequency modulation transfer function (MTF) and DQE values. The AAP design makes a separation of physical sensor elements from image pixels by using very small sensor elements (e.g. 0.010-0.025 mm) to synthesize desired larger image pixels (e.g. 0.1-0.2 mm). METHODS: A cascaded systems model of signal and noise propagation is developed to describe the benefits of the AAP approach in terms of the MTF, Wiener noise power spectrum (NPS) and DQE...
June 21, 2017: Medical Physics
https://www.readbyqxmd.com/read/28632501/evaluation-of-automatic-dose-rate-control-for-flat-panel-imaging-using-a-spatial-frequency-domain-figure-of-merit
#3
Michiel Dehairs, Hilde Bosmans, Walter Desmet, Nicholas W Marshall
Current automatic dose rate controls (ADRCs) of dynamic x-ray imaging systems adjust acquisition parameters in response to changes in patient thickness in order to achieve a constant signal level in the image receptor. This work compares a 3 parameter (3P) ADRC control to a more flexible 5-parameter (5P) method to meet this goal. A phantom composed of 15 composite poly(methyl) methacrylate (PMMA)/aluminium (Al) plates was imaged on a Siemens Artis Q dynamic system using standard 3P and 5P ADRC technique. Phantom thickness covered a water equivalent thickness range of 2...
June 20, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28626289/comparison-of-high-resolution-x-ray-detectors-with-conventional-fpds-using-experimental-mtfs-and-apodized-aperture-pixel-design-for-reduced-aliasing
#4
A Shankar, M Russ, S Vijayan, D R Bednarek, S Rudin
Apodized Aperture Pixel (AAP) design, proposed by Ismailova et. al, is an alternative to the conventional pixel design(1). The advantages of AAP processing with a sinc filter in comparison with using other filters include non-degradation of MTF values and elimination of signal and noise aliasing, resulting in an increased performance at higher frequencies, approaching the Nyquist frequency(3). If high resolution small field-of-view (FOV) detectors with small pixels used during critical stages of Endovascular Image Guided Interventions (EIGIs) could also be extended to cover a full field-of-view typical of flat panel detectors (FPDs) and made to have larger effective pixels, then methods must be used to preserve the MTF over the frequency range up to the Nyquist frequency of the FPD while minimizing aliasing...
February 11, 2017: Proceedings of SPIE
https://www.readbyqxmd.com/read/28618161/prevention-of-osteoporotic-refractures-in-regional-australia
#5
Emily Davidson, Alexa Seal, Zelda Doyle, Kerin Fielding, Joe McGirr
OBJECTIVE: Clinical guidelines recommend that patients who sustain a minimal trauma fracture (MTF) should receive a bone mineral density (BMD) scan and bisphosphonate (or equivalent) therapy if diagnosed with osteoporosis. A pilot fracture liaison service (FLS) was implemented in regional NSW to improve adherence to the guidelines. DESIGN: Prospective cohort study with an historical control. SETTING: Primary care. PARTICIPANTS: Control (n = 47) and cohort (n = 93) groups comprised patients consenting to interview who presented with a MTF to the major referral hospital 4 months before and 12 months after FLS implementation respectively...
June 15, 2017: Australian Journal of Rural Health
https://www.readbyqxmd.com/read/28615792/a-cmos-based-high-resolution-fluoroscope-hrf-detector-prototype-with-49-5-%C3%AE-m-pixels-for-use-in-endovascular-image-guided-interventions-eigi
#6
M Russ, A Shankar, S V Setlur Nagesh, C N Ionita, D R Bednarek, S Rudin
X-ray detectors to meet the high-resolution requirements for endovascular image-guided interventions (EIGIs) are being developed and evaluated. A new 49.5-micron pixel prototype detector is being investigated and compared to the current suite of high-resolution fluoroscopic (HRF) detectors. This detector featuring a 300-micron thick CsI(Tl) scintillator, and low electronic noise CMOS readout is designated the HRF-CMOS50. To compare the abilities of this detector with other existing high resolution detectors, a standard performance metric analysis was applied, including the determination of the modulation transfer function (MTF), noise power spectra (NPS), noise equivalent quanta (NEQ), and detective quantum efficiency (DQE) for a range of energies and exposure levels...
February 11, 2017: Proceedings of SPIE
https://www.readbyqxmd.com/read/28599997/translation-cultural-adaptation-and-preliminary-evaluation-of-the-spanish-version-of-the-transgender-voice-questionnaire-for-male-to-female-transsexuals-tvq-mtf
#7
Elena Mora, Alvaro Carrillo, Ana Giribet, Antonio Becerra, Ma Jesús Lucio, Ignacio Cobeta
OBJECTIVE: This study aimed to perform translation, cross-cultural adaptation, and validation of the Spanish version of the Transsexual Voice Questionnaire for Male-to-Female Transsexuals (TVQ (MtF)). STUDY DESIGN: This is a prospective study. SETTING: The study was conducted by the Gender Identity Unit and the Voice Unit of a tertiary hospital referral center for surgical feminization of the voice. SUBJECTS AND METHODS: The study had two parts: translation and adaptation of the TVQ (MtF) with the following actions: translation (with authorization and consensus of the authors of the original questionnaire), back-translation, pretesting, and final version; and preliminary study of the psychometric properties (feasibility, internal consistency, test-retest reliability, construct validity, discriminant validity, and ceiling and floor effects)...
June 6, 2017: Journal of Voice: Official Journal of the Voice Foundation
https://www.readbyqxmd.com/read/28586499/a-new-extended-depth-of-focus-intraocular-lens-based-on-spherical-aberration
#8
Roberto Bellucci, Maria C Curatolo
PURPOSE: To describe a new extended depth of focus intraocular lens (IOL) design offering multifocality by the variation of spherical aberration in the central optical zone. METHODS: The new IOL (Mini WELL; SIFI, Catania, Italy) is an aspheric IOL with positive spherical aberration in the central 2-mm zone and negative spherical aberration in the pericentral 1-mm annulus, the amount of which was determined by specific optic calculation. The new IOL design was tested at the optical bench to investigate depth of focus and sensitivity to tilt, decentration, and angle Kappa...
June 1, 2017: Journal of Refractive Surgery
https://www.readbyqxmd.com/read/28576481/ferrofluid-assisted-rapid-and-directional-harvesting-of-marine-microalgal-chlorella-sp-used-for-biodiesel-production
#9
Shih-Hsin Ho, Sheng-Yi Chiu, Chien-Ya Kao, Tsai-Yu Chen, Yu-Bin Chang, Jo-Shu Chang, Chih-Sheng Lin
In this work, a novel harvesting strategy using ferrofluids coupled with flocculation as a magnetic directional harvesting system was developed, providing a fast and easy way to effectively collect microalgae with no further modifications made to the ferrofluids. With a ferrofluid dosage of 25mgL(-1), a high harvesting efficiency of 95-100% was achieved within 1min. In addition, we successfully performed a wastewater recycling strategy coupled with a microalgal ferrofluid-harvesting dynamic flow-through system to harvest biomass of Chlorella sp...
May 20, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28574405/multi-institutional-microct-image-comparison-of-image-guided-small-animal-irradiators
#10
Chris Daniel Johnstone, Patricia Lindsay, Edward Graves, Eugene Wong, Jessica Perez, Yannick Poirier, Youssef Ben-Bouchta, Thilakshan Kanesalingam, Haijian Chen, Ashley Rubinstein, Ke Sheng, Magdalena Bazalova-Carter
To recommend imaging protocols and establish tolerance levels for microCT image quality assurance (QA) performed on conformal image-guided small animal irradiators. Method and Materials: A fully automated QA software SAPA (small animal phantom analyzer) for image analysis of the commercial Shelley micro-CT MCTP 610 phantom was developed, in which quantitative analyses of CT number linearity, signal-to-noise ratio (SNR), uniformity and noise, geometric accuracy, spatial resolution by means of modulation transfer function (MTF), and CT contrast were performed...
June 2, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28569999/second-generation-stationary-digital-breast-tomosynthesis-system-with-faster-scan-time-and-wider-angular-span
#11
Jabari Calliste, Gongting Wu, Philip E Laganis, Derrek Spronk, Houman Jafari, Kyle Olson, Bo Gao, Yueh Z Lee, Otto Zhou, Jianping Lu
PURPOSE: To characterize a new generation stationary digital breast tomosynthesis system with higher tube flux and increased angular span over a first generation system. METHODS: The linear CNT x-ray source was designed, built and evaluated to determine its performance parameters. The second generation system was then constructed using the CNT x-ray source and a Hologic gantry. Upon construction, test objects and phantoms were used to characterize system resolution as measured by the modulation transfer function (MTF), and artifact spread function (ASF)...
June 1, 2017: Medical Physics
https://www.readbyqxmd.com/read/28557801/a-comprehensive-model-for-x-ray-projection-imaging-system-efficiency-and-image-quality-characterization-in-the-presence-of-scattered-radiation
#12
P Monnin, F R Verdun, H Bosmans, S Rodríguez Pérez, N W Marshall
This work proposes a method for assessing the detective quantum efficiency (DQE) of radiographic imaging systems that include both the x-ray detector and the antiscatter device. Cascaded linear analysis of the antiscatter device efficiency (DQEASD) with the x-ray detector DQE is used to develop a metric of system efficiency (DQEsys); the new metric is then related to the existing system efficiency parameters of effective DQE (eDQE) and generalized DQE (gDQE). The effect of scatter on signal transfer was modelled through its point spread function (PSF), leading to an x-ray beam transfer function (BTF) that multiplies with the classical presampling modulation transfer function (MTF) to give the system MTF...
June 23, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28555935/a-novel-multi-layer-mv-imager-computational-model-for-component-optimization
#13
Marios Myronakis, Josh Star-Lack, Paul Baturin, Joerg Rottmann, Daniel Morf, Adam Wang, Yue-Houng Hu, Daniel Shedlock, Ross I Berbeco
PURPOSE: A novel Megavoltage (MV) multi-layer imager (MLI) design featuring higher detective quantum efficiency and lower noise than current conventional MV imagers in clinical use has been recently reported. Optimization of the MLI design for multiple applications including tumor tracking, MV-CBCT and portal dosimetry requires a computational model that will provide insight into the physics processes that affect the overall and individual components' performance. The purpose of the current work was to develop and validate a comprehensive computational model that can be used for MLI optimization...
May 29, 2017: Medical Physics
https://www.readbyqxmd.com/read/28551638/modulation-of-melanotransferrin-and-transferrin-receptor-1-tfrc-and-cd44-based-signaling-for-tfrc-up-regulation-in-human-melanoma-cells
#14
Friedemann Laube, Dagobert Glanz
BACKGROUND: The human melanoma cell line IGR-1 was used for the detection and regulation of both melanotransferrin (MTf) and transferrin receptor 1 (TFRC, CD71). While the function in iron transport of the TFRC is well documented the functional importance of MTf is not yet fully understood. Due to the up-regulation of TFRC by hyaluronan (HA) some components and aspects of CD44 signaling were investigated. MATERIALS AND METHODS: The cell-surface proteins MTf, TFRC and ERBB2 receptor tyrosine kinase 2 (ERBB2) were detected by immunoluminescent technique using different polyclonal and monoclonal antibodies...
June 2017: Anticancer Research
https://www.readbyqxmd.com/read/28529251/image-quality-and-clinical-usefulness-of-ray-summation-image-reconstructed-from-ct-data-compared-with-digital-radiography
#15
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
#16
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
#17
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
#18
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 CBCT in comparison with multislice spiral CT (MSCT) in scans of the head, cervical spine, ear and dental arches. METHODS: A head and neck Alderson-Rando(®) phantom (The Phantom Laboratory, Salem, NY) equipped with 74 thermoluminescence dosemeters was exposed according to 5 different scans in CBCT and 4 different scans in MSCT. Spatial and contrast resolutions, in terms of modulation transfer function and contrast-to-noise ratio (CNR), were measured to obtain a quantitative assessment of image quality...
June 20, 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
#19
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 30, 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
#20
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
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