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https://www.readbyqxmd.com/read/29346355/increasing-rates-of-people-identifying-as-transgender-presenting-to-endocrine-services-in-the-wellington-region
#1
John W Delahunt, Hayley J Denison, Dalice A Sim, Jemima J Bullock, Jeremy D Krebs
AIMS: Overseas clinics specialising in management of transgender people have noted a marked increase in the numbers of people requesting therapy in the last few years. No data has been presented for New Zealand. We therefore reviewed the number of transgender people seen in the Wellington Endocrine Service to assess if the pattern was similar and assess any potential problems for service delivery. METHODS: Using hospital records, we reviewed the new appointments of people who were referred for advice on gender reassignment and seen in the Wellington Endocrine Service from 1990 to 2016...
January 19, 2018: New Zealand Medical Journal
https://www.readbyqxmd.com/read/29328180/modulation-transfer-function-of-a-fish-eye-lens-based-on-the-sixth-order-wave-aberration-theory
#2
Han Jia, Lijun Lu, Yiqing Cao
A calculation program of the modulation transfer function (MTF) of a fish-eye lens is developed with the autocorrelation method, in which the sixth-order wave aberration theory of ultra-wide-angle optical systems is used to simulate the wave aberration distribution at the exit pupil of the optical systems. The autocorrelation integral is processed with the Gauss-Legendre integral, and the magnification chromatic aberration is discussed to calculate polychromatic MTF. The MTF calculation results of a given example are then compared with those previously obtained based on the fourth-order wave aberration theory of plane-symmetrical optical systems and with those from the Zemax program...
January 10, 2018: Applied Optics
https://www.readbyqxmd.com/read/29320304/complications-of-sling-surgery-for-stress-urinary-incontinence-among-female-military-beneficiaries
#3
David L Howard, Andrea McGlynn, Joy A Greer
BACKGROUND: Prior studies of complications after sling surgery excluded the large number of women in military treatment facilities (MTFs). OBJECTIVE: To characterize the postoperative complication rates after sling surgery for Stress urinary incontinence (SUI) within MTFs in the United States. MATERIALS AND METHODS: Retrospective cohort study of women aged 18 and older, with SUI, and who underwent either an outpatient or inpatient mid-urethral sling placement for SUI in any MTF in the United States between January 1, 2011 and December 31, 2012...
January 10, 2018: Journal of Women's Health
https://www.readbyqxmd.com/read/29297139/comparative-evaluation-of-image-quality-among-different-detector-configurations-using-area-detector-computed-tomography
#4
Yohei Miura, Katsuhiro Ichikawa, Ichiro Fujimura, Takanori Hara, Takashi Hoshino, Shinji Niwa, Masao Funahashi
The 320-detector row computed tomography (CT) system, i.e., the area detector CT (ADCT), can perform helical scanning with detector configurations of 4-, 16-, 32-, 64-, 80-, 100-, and 160-detector rows for routine CT examinations. This phantom study aimed to compare the quality of images obtained using helical scan mode with different detector configurations. The image quality was measured using modulation transfer function (MTF) and noise power spectrum (NPS). The system performance function (SP), based on the pre-whitening theorem, was calculated as MTF2/NPS, and compared between configurations...
January 2, 2018: Radiological Physics and Technology
https://www.readbyqxmd.com/read/29260730/measurement-of-effective-detective-quantum-efficiency-for-a-photon-counting-scanning-mammography-system-and-comparison-with-two-flat-panel-full-field-digital-mammography-systems
#5
Tim J Wood, Craig S Moore, John R Saunderson, Andy W Beavis
Effective Detective Quantum Efficiency (eDQE) describes the resolution and noise properties of an imaging system along with scatter and primary transmission, all measured under clinically appropriate conditions. Effective dose efficiency (eDE) is the eDQE normalised to mean glandular dose and has been proposed as a useful metric for the optimisation of clinical imaging systems. The aim of this study was to develop a methodology for measuring eDQE and eDE on a Philips MicroDose Mammography (MDM) L30 photon counting scanning system, and to compare performance with two conventional flat panel systems...
December 20, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/29250570/estimating-detectability-index-in-vivo-development-and-validation-of-an-automated-methodology
#6
Taylor Brunton Smith, Justin Solomon, Ehsan Samei
This study's purpose was to develop and validate a method to estimate patient-specific detectability indices directly from patients' CT images (i.e., in vivo). The method extracts noise power spectrum (NPS) and modulation transfer function (MTF) resolution properties from each patient's CT series based on previously validated techniques. These are combined with a reference task function (10-mm disk lesion with [Formula: see text] HU contrast) to estimate detectability indices for a nonprewhitening matched filter observer model...
July 2018: Journal of Medical Imaging
https://www.readbyqxmd.com/read/29242727/evaluation-of-cadmium-zinc-telluride-detector-based-single-photon-emission-computed-tomography-for-nuclear-cardiology-a-comparison-with-conventional-anger-single-photon-emission-computed-tomography
#7
Takanaga Niimi, Mamoru Nanasato, Mitsuo Sugimoto, Hisatoshi Maeda
Purpose: The differences in performance between the cadmium-zinc-telluride (CZT) camera or collimation systems and conventional Anger single-photon emission computed tomography (A-SPECT) remain insufficient from the viewpoint of the user. We evaluated the performance of the D-SPECT (Spectrum Dynamics, Israel) system to provide more information to the cardiologist or radiological technologist about its use in the clinical field. Materials and Methods: This study evaluated the performance of the D-SPECT system in terms of energy resolution, detector sensitivity, spatial resolution, modulation transfer function (MTF), and collimator resolution in comparison with that of A-SPECT (Bright-View, Philips, Japan)...
December 2017: Nuclear Medicine and Molecular Imaging
https://www.readbyqxmd.com/read/29235440/leveraging-multi-layer-imager-detector-design-to-improve-low-dose-performance-for-megavoltage-cone-beam-computed-tomography
#8
Yue-Houng Hu, Joerg Rottmann, Rony Fueglistaller, Marios E Myronakis, Adam Wang, Pascal Huber, Daniel Shedlock, Daniel Morf, Paul Baturin, Josh M Star-Lack, Ross I Berbeco
While megavoltage (MV) cone-beam computed tomography (CBCT) using an electronic portal imaging device (EPID) provides many advantages over kilovoltage (kV) CBCT, clinical adoption is limited by its high doses. Multi-layer imager (MLI) EPIDs increase DQE(0) while maintaining high resolution. However, even well-designed, high-performance MLIs suffer from increased electronic noise from each readout, degrading low-dose image quality. To improve low-dose performance, shift-and-bin addition (ShiBA) imaging is proposed, leveraging the unique architecture of the MLI...
December 13, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/29227508/laboratory-evaluation-of-the-influence-of-decentration-and-pupil-size-on-the-optical-performance-of-a-monofocal-bifocal-and-trifocal-intraocular-lens
#9
Tamer Tandogan, Hyeck Soo Son, Chul Young Choi, Michael C Knorz, Gerd U Auffarth, Ramin Khoramnia
PURPOSE: To assess the influence of decentration and aperture size on the optical quality of different intraocular lenses (IOLs) of the same material, body design, and refractive power using standardized optical bench testing. METHODS: Using an optical bench set-up, an aspheric monofocal (CT ASPHINA 409M; Carl Zeiss Meditec, Jena, Germany), an aspheric diffractive bifocal (AT LISA 809M; Carl Zeiss Meditec), and an aspheric diffractive trifocal (AT LISA 839M; Carl Zeiss Meditec) intraocular lens (IOL) were evaluated, each with the same distance power, body design, and material...
December 1, 2017: Journal of Refractive Surgery
https://www.readbyqxmd.com/read/29220101/report-of-aapm-task-group-162-software-for-planar-image-quality-metrology
#10
Ehsan Samei, Lynda C Ikejimba, Brian P Harrawood, John Rong, Ian A Cunningham, Michael J Flynn
PURPOSE: The AAPM Task Group 162 aimed to provide a standardized approach for the assessment of image quality in planar imaging systems. This report offers a description of the approach as well as the details of the resultant software bundle to measure detective quantum efficiency (DQE) as well as its basis components and derivatives. METHODS: The methodology and the associated software include the characterization of the noise power spectrum (NPS) from planar images acquired under specific acquisition conditions, modulation transfer function (MTF) using an edge test object, the DQE, and effective DQE (eDQE)...
December 8, 2017: Medical Physics
https://www.readbyqxmd.com/read/29219018/gender-differences-in-knee-joint-congruity-quantified-from-mri-a-validation-study-with-data-from-center-for-clinical-and-basic-research-and-osteoarthritis-initiative
#11
Sudhakar Tummala, Dieuwke Schiphof, Inger Byrjalsen, Erik B Dam
Objective Gender is a risk factor in the onset of osteoarthritis (OA). The aim of the study was to investigate gender differences in contact area (CA) and congruity index (CI) in the medial tibiofemoral (MTF) joint in 2 different cohorts, quantified automatically from magnetic resonance imaging (MRI). Design The CA and CI markers were validated on 2 different data sets from Center for Clinical and Basic Research (CCBR) and Osteoarthritis Initiative (OAI). The CCBR cohort consisted of 159 subjects and the OAI subcohort consisted of 1,436 subjects...
January 2018: Cartilage
https://www.readbyqxmd.com/read/29216094/analysis-and-reduction-of-the-tdi-ccd-charge-transfer-image-shift
#12
Yun-Hui Li, Xiao-Dong Wang, Wen-Guang Liu, Zhi Wang
Based on the description of the charge transfer process of a time delay integration charge coupled device (TDI CCD), it is pointed out that the relative displacement of the target image and the transferred charge introduces the charge transfer image shift problem in a line transfer period, which leads to the decrease of the modulation transfer function (MTF) in the scanning direction. Based on the basic definition of MTF, the charge transfer image shift model of the TDI CCD is established. According to the quantitative calculation of this model, the MTF curves of the three-phase TDI CCD are obtained under the condition of different pulse widths of computer interface (CI) signals...
November 20, 2017: Applied Optics
https://www.readbyqxmd.com/read/29197583/evaluation-of-ion-mobility-for-the-separation-of-glycoconjugate-isomers-due-to-different-types-of-sialic-acid-linkage-at-the-intact-glycoprotein-glycopeptide-and-glycan-level
#13
Albert Barroso, Estela Giménez, Albert Konijnenberg, Jaime Sancho, Victoria Sanz-Nebot, Frank Sobott
The study of protein glycosylation can be regarded as an intricate but very important task, making glycomics one of the most challenging and interesting, albeit under-researched, type of "omics" science. Complexity escalates remarkably when considering that carbohydrates can form severely branched structures with many different constituents, which often leads to the formation of multiple isomers. In this regard, ion mobility (IM) spectrometry has recently demonstrated its power for the separation of isomeric compounds...
November 29, 2017: Journal of Proteomics
https://www.readbyqxmd.com/read/29189963/multiple-true-false-items-a-comparison-of-scoring-algorithms
#14
Felicitas-Maria Lahner, Andrea Carolin Lörwald, Daniel Bauer, Zineb Miriam Nouns, René Krebs, Sissel Guttormsen, Martin R Fischer, Sören Huwendiek
Multiple true-false (MTF) items are a widely used supplement to the commonly used single-best answer (Type A) multiple choice format. However, an optimal scoring algorithm for MTF items has not yet been established, as existing studies yielded conflicting results. Therefore, this study analyzes two questions: What is the optimal scoring algorithm for MTF items regarding reliability, difficulty index and item discrimination? How do the psychometric characteristics of different scoring algorithms compare to those of Type A questions used in the same exams? We used data from 37 medical exams conducted in 2015 (998 MTF and 2163 Type A items overall)...
November 30, 2017: Advances in Health Sciences Education: Theory and Practice
https://www.readbyqxmd.com/read/29189636/mitochondrial-fusion-and-fission-proteins-and-the-recognition-memory-of-imprinting-in-domestic-chicks
#15
Giorgi Margvelani, Maia Meparishvili, Ekaterine Tevdoradze, Brian J McCabe, Revaz Solomonia
Visual imprinting is a learning process through which young, visually naive animals come to recognize a visual stimulus by being exposed to it (training) and subsequently approach the stimulus in preference to others. A large body of evidence indicates that a restricted part of the forebrain, the intermediate medial mesopallium (IMM), is a memory region for visual imprinting in the domestic chick. Previous studies have shown learning-related up-regulation of several mitochondrial proteins in the IMM 24 h after training...
November 17, 2017: Neuroreport
https://www.readbyqxmd.com/read/29188125/direct-inversion-algorithm-for-focal-plane-scanning-optical-projection-tomography
#16
Kevin G Chan, Michael Liebling
To achieve approximately parallel projection geometry, traditional optical projection tomography (OPT) requires the use of low numerical aperture (NA) objectives, which have a long depth-of-field at the expense of poor lateral resolution. Particularly promising methods to improve spatial resolution include ad-hoc post-processing filters that limit the effect of the system's MTF and focal-plane-scanning OPT (FPS-OPT), an alternative acquisition procedure that allows the use of higher NA objectives by limiting the effect of their shallow depth of field yet still assumes parallel projection rays during reconstruction...
November 1, 2017: Biomedical Optics Express
https://www.readbyqxmd.com/read/29185436/objective-image-characterization-of-a-spectral-ct-scanner-with-dual-layer-detector
#17
Orhan Ozguner, Amar Dhanantwari, Sandra Halliburton, Gezheng Wen, Steven Utrup, David W Jordan
This work evaluated the performance of a detector-based spectral CT system by obtaining objective reference data, evaluating attenuation response of iodine and accuracy of iodine quantification, and comparing conventional CT and virtual monoenergetic images in three common phantoms. Scanning was performed using the hospital's clinical adult body protocol. Modulation transfer function (MTF) was calculated for a tungsten wire and visual line pair targets were evaluated. Image noise power spectrum (NPS) and pixel standard deviation were calculated...
November 29, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/29182054/a-quantitative-method-for-the-evaluation-of-spatial-resolution-in-quality-control-of-b-mode-ultrasound-images
#18
Sabina Strocchi, Francesco Larghi, Raffaele Novario
The work describes a method to quantitatively evaluate spatial resolution in B-mode quality control images as radial modulation transfer function (MTF). The method is easy to use in in-field quality assurance programs in clinical institutions, as it is fast and can be performed with the help of phantoms that are already used for routine quality control. It uses a round insert with different echogenic characteristics compared with the phantom background. The method was automated with a MATLAB® routine, which can be run in full automatic mode or with a grade of interaction by the user, as is sometimes necessary with low-quality images...
November 1, 2017: Ultrasonic Imaging
https://www.readbyqxmd.com/read/29179010/method-for-estimating-modulation-transfer-function-from-sample-images
#19
Rino Saiga, Akihisa Takeuchi, Kentaro Uesugi, Yasuko Terada, Yoshio Suzuki, Ryuta Mizutani
The modulation transfer function (MTF) represents the frequency domain response of imaging modalities. Here, we report a method for estimating the MTF from sample images. Test images were generated from a number of images, including those taken with an electron microscope and with an observation satellite. These original images were convolved with point spread functions (PSFs) including those of circular apertures. The resultant test images were subjected to a Fourier transformation. The logarithm of the squared norm of the Fourier transform was plotted against the squared distance from the origin...
November 22, 2017: Micron: the International Research and Review Journal for Microscopy
https://www.readbyqxmd.com/read/29169588/changes-in-hormonal-and-metabolic-parameters-in-transgender-subjects-on-cross-sex-hormone-therapy-a-cohort-study
#20
Roberto Vita, Salvatore Settineri, Marco Liotta, Salvatore Benvenga, Francesco Trimarchi
OBJECTIVES: Gender identity disorder is defined as a strong and persistent cross-gender identification that is associated with a remarkable uneasiness of living in an incongruent gender (gender dysphoria). We performed a retrospective study on the hormonal and metabolic effects of cross-sex hormone therapy (CSHT) in a small cohort of transgender patients. STUDY DESIGN: Retrospective study. MEAN OUTCOME MEASURES: Hormonal and biochemical parameters at baseline (i...
January 2018: Maturitas
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