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https://www.readbyqxmd.com/read/28522170/optimization-of-the-alpha-image-reconstruction-an-iterative-ct-image-reconstruction-with-well-defined-image-quality-metrics
#1
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/28506822/the-effect-of-prophylactic-vertebroplasty-on-the-incidence-of-proximal-junctional-kyphosis-and-proximal-junctional-failure-following-posterior-spinal-fusion-in-adult-spinal-deformity-a-5-year-follow-up-study
#2
Tina Raman, Emily Miller, Christopher T Martin, Khaled Kebaish
BACKGROUND CONTEXT: The incidence of proximal junctional kyphosis (PJK) ranges from 5-46% following adult spinal deformity (ASD) surgery. Approximately 66-76% of PJK occurs within 3 months of surgery. A subset of these patients, reportedly 26-47%, develop proximal junctional failure (PJF) within 6 months postoperatively. To date, there are no studies evaluating the impact of prophylactic vertebroplasty on PJK/PJF incidence at long term follow-up. PURPOSE: The purpose of this study is to evaluate the long term radiographic and clinical outcomes, and incidence of PJK and PJF, after prophylactic vertebroplasty for long segment thoracolumbar posterior spinal fusion...
May 12, 2017: Spine Journal: Official Journal of the North American Spine Society
https://www.readbyqxmd.com/read/28483068/factors-associated-with-multidimensional-aspect-of-post-stroke-fatigue-in-acute-stroke-period
#3
Hitoshi Mutai, Tomomi Furukawa, Ayumi Houri, Akihito Suzuki, Tokiji Hanihara
BACKGROUND: Post-stroke fatigue (PSF) is a frequent and distressing consequence of stroke, and can be both acute and long lasting. We aimed to investigate multidimensional aspects of acute PSF and to determine the clinical factors relevant to acute PSF. METHODS: We collected data of 101 patients admitted to the hospital for acute stroke. PSF was assessed using the Multidimensional Fatigue Inventory within 2 weeks of stroke. Measures included Mini-Mental State Examination, Hospital Anxiety and Depression Scale, and Functional Independence Measure...
April 2017: Asian Journal of Psychiatry
https://www.readbyqxmd.com/read/28476052/measuring-forward-light-scatter-by-the-boston-keratoprosthesis-in-various-configurations
#4
Musa Abdelaziz, Claes H Dohlman, Rony R Sayegh
PURPOSE: Light scatter results in degradation of visual function. An optical bench model was used to identify the origins of scatter in the setting of a Boston keratoprosthesis (KPro). The effect of various modifications in the device design and light-blocking configurations was explored. METHODS: A KPro was mounted on a contact lens holder on a bench, and forward light scatter was recorded with a camera attached to a rotating goniometer arm. Scattered light was recorded at different angles for different KPro modifications, and the point-spread function (PSF) curves were recorded...
June 2017: Cornea
https://www.readbyqxmd.com/read/28468374/point-spread-function-and-depth-invariant-focal-sweep-point-spread-function-for-plenoptic-camera-2-0
#5
Xin Jin, Li Liu, Yanqin Chen, Qionghai Dai
This paper derives a mathematical point spread function (PSF) and a depth-invariant focal sweep point spread function (FSPSF) for plenoptic camera 2.0. Derivation of PSF is based on the Fresnel diffraction equation and image formation analysis of a self-built imaging system which is divided into two sub-systems to reflect the relay imaging properties of plenoptic camera 2.0. The variations in PSF, which are caused by changes of object's depth and sensor position variation, are analyzed. A mathematical model of FSPSF is further derived, which is verified to be depth-invariant...
May 1, 2017: Optics Express
https://www.readbyqxmd.com/read/28468359/chromatic-aberration-control-with-liquid-crystal-spatial-phase-modulators
#6
Jose L Martinez, Enrique J Fernandez, Pedro M Prieto, Pablo Artal
The chromatic behavior of diffractive optical elements, exhibiting 2π-wrapped phase profiles, implemented into liquid crystal spatial light modulators (LC-SLM) is described. A wrapped phase map is only equivalent to the original continuous profile for the design wavelength while at other wavelengths there are unwanted phase jumps and the profile does not correspond to a pure defocus. For those conditions the wrapped profile behaves as a multiple order lens (multi-focal lens). The optical power dispersion for each order is linearly proportional to the wavelength, while the energy of each order depends on the design wavelength and the material dispersion...
May 1, 2017: Optics Express
https://www.readbyqxmd.com/read/28464653/increasing-circular-synthetic-aperture-sonar-resolution-via-adapted-wave-atoms-deconvolution
#7
Yan Pailhas, Yvan Petillot, Bernard Mulgrew
Circular Synthetic Aperture Sonar (CSAS) processing computes coherently Synthetic Aperture Sonar (SAS) data acquired along a circular trajectory. This approach has a number of advantages, in particular it maximises the aperture length of a SAS system, producing very high resolution sonar images. CSAS image reconstruction using back-projection algorithms, however, introduces a dissymmetry in the impulse response, as the imaged point moves away from the centre of the acquisition circle. This paper proposes a sampling scheme for the CSAS image reconstruction which allows every point, within the full field of view of the system, to be considered as the centre of a virtual CSAS acquisition scheme...
April 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28444524/in-vitro-optical-quality-of-monofocal-aspheric-toric-intraocular-lenses-effect-of-cylindrical-power
#8
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/28441684/development-of-consensus-based-best-practice-guidelines-for-postoperative-care-following-posterior-spinal-fusion-for-adolescent-idiopathic-scoliosis
#9
Nicholas D Fletcher, Michael P Glotzbecker, Michelle Marks, Peter O Newton
STUDY DESIGN: Delphi process with multiple iterative rounds using a nominal group technique. OBJECTIVE: The aim of this study was to use expert opinion to achieve consensus on various aspects of postoperative care following posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: Significant variability exists in postoperative care following PSF for AIS, despite a relatively healthy patient population and continuously improving operative techniques...
May 1, 2017: Spine
https://www.readbyqxmd.com/read/28441311/feasibility-and-outcome-of-an-accelerated-recovery-protocol-in-asian-adolescent-idiopathic-scoliosis-patients
#10
Chris Yin Wei Chan, Shweh Fern Loo, Jun Yin Ong, Kulathunga Arachchige Lisitha, M Shahnaz Hasan, Chee Kean Lee, Chee Kidd Chiu, Mun Keong Kwan
STUDY DESIGN: Prospective cohort study OBJECTIVE.: To determine the feasibility of an accelerated recovery protocol for Asian Adolescent Idiopathic Scoliosis (AIS) patients undergoing posterior spinal fusion (PSF). SUMMARY OF BACKGROUND DATA: There has been successful implementation of an accelerated recovery protocol for AIS patients undergoing PSF in the western population. No similar studies have been reported in the Asian population. METHODS: 74 AIS (65F, 9 M) patients scheduled for PSF surgery were recruited...
April 24, 2017: Spine
https://www.readbyqxmd.com/read/28439979/scattering-contribution-to-the-double-pass-psf-using-monte-carlo-simulations
#11
Dimitrios Christaras, Harilaos Ginis, Alexandros Pennos, Pablo Artal
PURPOSE: Scattering in the eye occurs mainly at two sites: the eye's optical media and the deeper retinal layers. Although the two phenomena are often treated collectively, their spatial domain of contribution to the double-pass Point Spread Function (PSF) is different: the fundus effect is limited to the narrow and middle part of the PSF whereas scattering in the eye's optics extends also to wide angles. The objective of this work was to determine the domain of contribution at the double-pass PSF of light scattered in the ocular media and the ocular fundus, using simulated and experimental data for two different wavelengths and for two different pigmentations...
May 2017: Ophthalmic & Physiological Optics: the Journal of the British College of Ophthalmic Opticians (Optometrists)
https://www.readbyqxmd.com/read/28424211/connecting-tubule-glomerular-feedback-mediates-tubuloglomerular-feedback-resetting-post-unilateral-nephrectomy
#12
Sumit R Monu, Yilin Ren, J X Masjoan Juncos, Kristopher Kutskill, Hong Wang, Nitin Kumar, Edward L Peterson, Oscar A Carretero
Unilaterally nephrectomized rats (UNx) have higher glomerular capillary pressure (PGC) that can cause significant glomerular injury in the remnant kidney. PGC is controlled by the ratio of afferent (Af-Art) and efferent arteriole resistance. Af-Art resistance in turn is regulated by two intrinsic feedback mechanisms: 1) Tubuloglomerular feedback (TGF) that causes Af-Art constriction in response to increased NaCl in the macula densa and 2) connecting tubule glomerular feedback (CTGF) that causes Af-Art dilatation in response to an increase in NaCl transport in the connecting tubule via the epithelial sodium channel (ENaC)...
April 19, 2017: American Journal of Physiology. Renal Physiology
https://www.readbyqxmd.com/read/28419517/comparative-analysis-between-rq-pcr-and-digital-droplet-pcr-of-bcl2-igh-gene-rearrangement-in-the-peripheral-blood-and-bone-marrow-of-early-stage-follicular-lymphoma
#13
Marzia Cavalli, Lucia Anna De Novi, Irene Della Starza, Luca Vincenzo Cappelli, Vittorio Nunes, Alessandro Pulsoni, Ilaria Del Giudice, Anna Guarini, Robin Foà
BCL2/IGH rearrangements were analysed by polymerase chain reaction (PCR) at diagnosis in paired peripheral blood (PB) and bone marrow (BM) samples from 67 patients with stage I/II follicular lymphoma (FL). Real time quantitative PCR (RQ-PCR) and digital droplet PCR (ddPCR) were performed in cases with a major breakpoint region (MBR+) at diagnosis and after localized radiotherapy and rituximab administration in order to investigate the applicability of ddPCR. The overall ddPCR/RQ-PCR concordance was 81·9% (113/138 samples) and 97·5% in the 40/138 with quantifiable disease (RQ-PCR≥10(-5) )...
April 17, 2017: British Journal of Haematology
https://www.readbyqxmd.com/read/28419433/plant-soil-feedbacks-in-declining-forests-implications-for-species-coexistence
#14
Lorena Gómez-Aparicio, Jara Domínguez-Begines, Paul Kardol, José M Ávila, Beatriz Ibáñez, Luis V García
Plant-soil feedbacks (PSFs) play a relevant role as drivers of species abundance, coexistence, and succession in plant communities. However, the potential contribution of PSFs to community dynamics in changing forest ecosystems affected by global change drivers is still largely unexplored. We measured the direction, strength and nature (biological vs. chemical) of PSFs experienced by coexisting tree species in two types of declining Quercus suber forests of southwestern Spain (open woodland vs. closed forest) invaded by the exotic soil pathogen Phytophthora cinnamomi...
April 18, 2017: Ecology
https://www.readbyqxmd.com/read/28415646/combination-of-immunohistochemistry-fish-and-rt-pcr-shows-high-incidence-of-xp11-translocation-rcc-comparison-of-three-different-diagnostic-methods
#15
Hyun Jung Lee, Dong Hoon Shin, Gyu You Noh, Young Keum Kim, Ahrong Kim, Nari Shin, Jung Hee Lee, Kyung Un Choi, Jee Yeon Kim, Chang Hun Lee, Mee Young Sol, Seo Hee Rha, Sung Woo Park
We evaluated the frequency of translocation renal cell carcinoma (RCC) by reverse transcription polymerase chain reaction (RT-PCR) and how well the TFE3 immunoreactivity is concordant with TFE3 gene translocation status proved by fluorescence in situ hybridization (FISH) assay and RT-PCR. TFE3 and Cathepsin K expression was analyzed by immunohistochemistry in 185 RCC cases, and 48 cases either of more than weak expression of TFE3 or of positivity for Cathepsin K were done for FISH analysis and RT-PCR. All the RT-PCR positive cases were confirmed by cloning and sequencing...
May 9, 2017: Oncotarget
https://www.readbyqxmd.com/read/28405294/dissecting-solidago-canadensis-soil-feedback-in-its-real-invasion
#16
Li-Jia Dong, Jian-Xia Yang, Hong-Wei Yu, Wei-Ming He
The importance of plant-soil feedback (PSF) has long been recognized, but the current knowledge on PSF patterns and the related mechanisms mainly stems from laboratory experiments. We aimed at addressing PSF effects on community performance and their determinants using an invasive forb Solidago canadensis. To do so, we surveyed 81 pairs of invaded versus uninvaded plots, collected soil samples from these pairwise plots, and performed an experiment with microcosm plant communities. The magnitudes of conditioning soil abiotic properties and soil biotic properties by S...
April 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28399049/evaluation-of-gabapentin-and-clonidine-use-in-children-following-spinal-fusion-surgery-for-idiopathic-scoliosis-a-retrospective-review
#17
Dinesh K Choudhry, B Randall Brenn, Karen Sacks, Suken Shah
BACKGROUND: Opioids are the mainstay of therapy for pain relief following posterior spinal fusion (PSF) surgery. Various adjunctive medications are being used to augment analgesia and to reduce opioid-related side effects. At our institution, we have sequentially added 2 adjuncts to a standard morphine patient-controlled analgesia (PCA) regimen. The goal of our study was to evaluate pain control and the benefit of gabapentin and the combination of gabapentin and clonidine, whereas morphine PCA was in use in children following PSF surgery...
April 10, 2017: Journal of Pediatric Orthopedics
https://www.readbyqxmd.com/read/28397612/adolescent-friendships-predict-later-resilient-functioning-across-psychosocial-domains-in-a-healthy-community-cohort
#18
A-L van Harmelen, R A Kievit, K Ioannidis, S Neufeld, P B Jones, E Bullmore, R Dolan, P Fonagy, I Goodyer
BACKGROUND: Adolescence is a key time period for the emergence of psychosocial and mental health difficulties. To promote adolescent adaptive ('resilient') psychosocial functioning (PSF), appropriate conceptualisation and quantification of such functioning and its predictors is a crucial first step. Here, we quantify resilient functioning as the degree to which an individual functions better or worse than expected given their self-reported childhood family experiences, and relate this to adolescent family and friendship support...
April 11, 2017: Psychological Medicine
https://www.readbyqxmd.com/read/28394818/optimization-of-pet-ct-image-quality-using-the-ge-sharp-ir-point-spread-function-reconstruction-algorithm
#19
Nicholas J Vennart, Nicholas Bird, John Buscombe, Heok K Cheow, Ewa Nowosinska, Sarah Heard
OBJECTIVE: The objective of this study was to quantify any improvement with the GE 'Sharp IR' point-spread function (PSF) reconstruction algorithm in addition to ordered subsets expectation maximum (OSEM) and time-of-flight (TOF) reconstruction algorithms and establish the optimum parameters to be used in clinical studies. MATERIALS AND METHODS: We conducted a range of experiments using the National Electrical Manufacturers Association image quality phantom filled with a 4 : 1 signal-to-background ratio...
June 2017: Nuclear Medicine Communications
https://www.readbyqxmd.com/read/28387991/endoscopic-chemocauterization-for-pyriform-sinus-fistulas-in-children
#20
Satohiko Yanagisawa, Takehito Oshio, Mototoshi Kato, Motohiro Kano, Yuki Tsuji, Yasuhide Morikawa
PURPOSE: Although complete excision is the standard treatment for pyriform sinus fistula (PSF), it has recently been suggested that chemocauterization via the internal orifice of the fistula could be an effective non-invasive treatment for the condition. The present report describes the details of our experience and the efficacy of endoscopic chemocauterization for pediatric PSF. METHOD: Between January 2010 and June 2015, 4 patients were diagnosed with PSF and scheduled to undergo endoscopic chemocauterization...
April 7, 2017: Pediatrics International: Official Journal of the Japan Pediatric Society
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