keyword
MENU ▼
Read by QxMD icon Read
search

frequency compression

keyword
https://www.readbyqxmd.com/read/28735201/ultrasound-elastography-of-the-prostate-using-an-unconstrained-modulus-reconstruction-technique-a-pilot-clinical-study
#1
REVIEW
Seyed Reza Mousavi, Hassan Rivaz, Gregory J Czarnota, Abbas Samani, Ali Sadeghi-Naini
A novel full-inversion-based technique for quantitative ultrasound elastography was investigated in a pilot clinical study on five patients for non-invasive detection and localization of prostate cancer and quantification of its extent. Conventional-frequency ultrasound images and radiofrequency (RF) data (~5 MHz) were collected during mechanical stimulation of the prostate using a transrectal ultrasound probe. Pre and post-compression RF data were used to construct the strain images. The Young's modulus (YM) images were subsequently reconstructed using the derived strain images and the stress distribution estimated iteratively using finite element (FE) analysis...
July 20, 2017: Translational Oncology
https://www.readbyqxmd.com/read/28727550/isar-imaging-of-high-speed-maneuvering-target-using-gapped-stepped-frequency-waveform-and-compressive-sensing
#2
Min-Seok Kang, Seung-Jae Lee, Seong-Hyeon Lee, Kyung-Tae Kim
In the case of a stepped-frequency waveform (SFW) inverse synthetic aperture radar (ISAR) system, the translational motion (TM) of a target can be usually divided into two parts: 1) target motion within a pulse repetition interval (PRI), called the inter-pulse translational motion (IPTM) and 2) target motion between bursts, called the inter-burst translational motion (IBTM). The former induces severe blurring in the ISAR images as well as range-compressed data (i.e., range profile), and the latter also causes dramatic degradation of the ISAR image quality...
July 17, 2017: IEEE Transactions on Image Processing: a Publication of the IEEE Signal Processing Society
https://www.readbyqxmd.com/read/28726592/effect-of-extreme-adaptive-frequency-compression-in-bimodal-listeners-on-sound-localization-and-speech-perception
#3
Lidwien C E Veugen, Josef Chalupper, Lucas H M Mens, Ad F M Snik, A John van Opstal
OBJECTIVES: This study aimed to improve access to high-frequency interaural level differences (ILD), by applying extreme frequency compression (FC) in the hearing aid (HA) of 13 bimodal listeners, using a cochlear implant (CI) and conventional HA in opposite ears. DESIGN: An experimental signal-adaptive frequency-lowering algorithm was tested, compressing frequencies above 160 Hz into the individual audible range of residual hearing, but only for consonants (adaptive FC), thus protecting vowel formants, with the aim to preserve speech perception...
July 20, 2017: Cochlear Implants International
https://www.readbyqxmd.com/read/28719550/does-an-annular-puncture-influence-the-herniation-path-an-in-vitro-mechanical-and-structural-investigation
#4
Vonne M van Heeswijk, Ashvin Thambyah, Peter A Robertson, Neil D Broom
STUDY DESIGN: A study of mechanically-induced herniation in punctured ovine discs followed by structural analysis. OBJECTIVE: To investigate whether an annular puncture influences the path that herniation takes by providing direct passage for nucleus through the annulus and therefore whether it increases the risk of acute herniation from overload at the site of damage independent of any longer-term degeneration. SUMMARY OF BACKGROUND DATA: 10 years after treatment with discography both degenerative changes and frequency of herniation have been shown to increase compared to untreated discs...
July 17, 2017: Spine
https://www.readbyqxmd.com/read/28718710/compressed-air-noise-reductions-from-using-advanced-air-gun-nozzles-in-research-and-development-environments
#5
Kurt Prieve, Amanda Rice, Peter C Raynor
The aims of this study were to evaluate sound levels produced by compressed air guns in research and development (R&D) environments, replace conventional air gun models with advanced noise-reducing air nozzles, and measure changes in sound levels to assess the effectiveness of the advanced nozzles as engineering controls for noise. Ten different R&D manufacturing areas that used compressed air guns were identified and included in the study. A-weighted sound level and Z-weighted octave band measurements were taken simultaneously using a single instrument...
August 2017: Journal of Occupational and Environmental Hygiene
https://www.readbyqxmd.com/read/28718671/freeze-dried-and-irradiated-allograft-bone-combined-with-fresh-autologous-coagula-promotes-angiogenesis-in-an-ectopic-bone-allograft-implantation-model
#6
Haibo Lu, Haoye Meng, Shibi Lu, Ling Qin, Bin Zhao, Aiyuan Wang, Jiang Peng, Wenjing Xu, Quanyi Guo, Jian Zhang
BACKGROUND: Freeze-dried and irradiated allograft bone (FIAB) is more easily impacted than fresh-frozen allograft bone (FAB) but has weaker incorporation efficiency. We combined FIAB with fresh autologous coagula to enhance donor-host incorporation after impaction during hip revision. METHODS: Thirty adult male Sprague-Dawley rats were sacrificed for bone allograft harvesting, and nine male rats were subjected to ectopic bone allograft implantation. For each rat, the container on the left (study) side was filled with freeze-dried allograft bone powder and fresh autologous blood coagula, whereas the right (control) side was filled with freeze-dried allograft bone powder and physiological saline...
July 18, 2017: Connective Tissue Research
https://www.readbyqxmd.com/read/28713841/design-and-implementation-of-an-optimal-laser-pulse-front-tilting-scheme-for-ultrafast-electron-diffraction-in-reflection-geometry-with-high-temporal-resolution
#7
Francesco Pennacchio, Giovanni M Vanacore, Giulia F Mancini, Malte Oppermann, Rajeswari Jayaraman, Pietro Musumeci, Peter Baum, Fabrizio Carbone
Ultrafast electron diffraction is a powerful technique to investigate out-of-equilibrium atomic dynamics in solids with high temporal resolution. When diffraction is performed in reflection geometry, the main limitation is the mismatch in group velocity between the overlapping pump light and the electron probe pulses, which affects the overall temporal resolution of the experiment. A solution already available in the literature involved pulse front tilt of the pump beam at the sample, providing a sub-picosecond time resolution...
July 2017: Structural Dynamics (Melville, N.Y.)
https://www.readbyqxmd.com/read/28712173/surgical-site-infection-in-orthopaedic-implants-and-its-common-bacteria-with-their-sensitivities-to-antibiotics-in-open-reduction-internal-fixation
#8
Muhammad Qaisar Shah, Muhammad Shoib Zardad, Alamzeb Khan, Sajjad Ahmed, Abdus Saboor Awan, Taj Mohammad
BACKGROUND: Surgical site infection in orthopaedic implants is a major problem, causing long hospital stay, cost to the patient and is a burden on health care facilities. It increases rate of nonunion, osteomyelitis, implant failure, sepsis, multiorgan dysfunction and even death. Surgical site infection is defined as pain, erythema, swelling and discharge from wound site. Surgical site infection in orthopaedic implants is more challenging to the treating orthopaedic surgeon as the causative organism is protected by a biofilm over the implant's surface...
January 2017: Journal of Ayub Medical College, Abbottabad: JAMC
https://www.readbyqxmd.com/read/28709218/transient-hydrodynamic-finite-size-effects-in-simulations-under-periodic-boundary-conditions
#9
Adelchi J Asta, Maximilien Levesque, Rodolphe Vuilleumier, Benjamin Rotenberg
We use lattice-Boltzmann and analytical calculations to investigate transient hydrodynamic finite-size effects induced by the use of periodic boundary conditions. These effects are inevitable in simulations at the molecular, mesoscopic, or continuum levels of description. We analyze the transient response to a local perturbation in the fluid and obtain the local velocity correlation function via linear response theory. This approach is validated by comparing the finite-size effects on the steady-state velocity with the known results for the diffusion coefficient...
June 2017: Physical Review. E
https://www.readbyqxmd.com/read/28708158/silicon-microring-modulator-based-rf-mixer-for-millimeter-wave-phase-coded-signal-generation
#10
Yiwei Xie, Leimeng Zhuang, Arthur James Lowery
Phase-coded radio frequency (RF) pulses are widely adopted for radar systems as an effective signal format to enable high-range resolution. However, generating such signals conventionally requires high-speed electronics and complex RF circuitry that impose burdens on the system cost and power consumption. In particular, modern radar systems desire features such as high frequencies, e.g., in the millimeter-wave region, high compactness, and high system flexibility, which pose great challenges for the conventional all-electronics solutions...
July 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/28708152/optical-frequency-comb-generation-with-ultra-narrow-spectral-lines
#11
M Imrul Kayes, Martin Rochette
We demonstrate an optical comb source that generates 550 ultra-narrow spectral lines with a spectral linewidth of 1.5-3 kHz, spanning over the C-band. The source originates from a single-mode Brillouin laser processed with phase modulation, pulse compression, and four-wave mixing. As a result, the narrow linewidth of the Brillouin laser improves the phase noise of every spectral line of the frequency comb.
July 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/28705829/regional-variation-in-undulatory-kinematics-of-two-hammerhead-species-the-bonnethead-sphyrna-tiburo-and-the-scalloped-hammerhead-sphyrna-lewini
#12
S L Hoffmann, S M Warren, M E Porter
Hammerhead sharks (Sphyrnidae) are have a large amount of morpholigcal variation within the family, making them the focus of many studies. The size of the laterally expanded head, or cephalofoil, is inversely correlated with pectoral fin area. The inverse relation in cephalofoil and pectoral fin size in this family suggests that they might serve a complimentary role in lift generation. The cephalofoil is also hypothesized to increase olfaction, electroreception, and vision; however, little is known about how morphological variation impacts post-cranial swimming kinematics...
July 13, 2017: Journal of Experimental Biology
https://www.readbyqxmd.com/read/28705608/the-impact-of-hearing-aids-and-age-related-hearing-loss-on-auditory-plasticity-across-three-months-an-electrical-neuroimaging-study
#13
Nathalie Giroud, Ulrike Lemke, Philip Reich, Katarina L Matthes, Martin Meyer
The present study investigates behavioral and electrophysiological auditory and cognitive-related plasticity in three groups of healthy older adults (60-77 years). Group 1 was moderately hearing-impaired, experienced hearing aid users, and fitted with new hearing aids using non-linear frequency compression (NLFC on); Group 2, also moderately hearing-impaired, used the same type of hearing aids but NLFC was switched off during the entire period of study duration (NLFC off); Group 3 represented individuals with age-appropriate hearing (NHO) as controls, who were not different in IQ, gender, or age from Group 1 and 2...
June 29, 2017: Hearing Research
https://www.readbyqxmd.com/read/28704945/a-study-on-the-data-compression-technology-based-intelligent-data-acquisition-idaq-system-for-structural-health-monitoring-of-civil-structures
#14
Gwanghee Heo, Joonryong Jeon
In this paper, a data compression technology-based intelligent data acquisition (IDAQ) system was developed for structural health monitoring of civil structures, and its validity was tested using random signals (El-Centro seismic waveform). The IDAQ system was structured to include a high-performance CPU with large dynamic memory for multi-input and output in a radio frequency (RF) manner. In addition, the embedded software technology (EST) has been applied to it to implement diverse logics needed in the process of acquiring, processing and transmitting data...
July 12, 2017: Sensors
https://www.readbyqxmd.com/read/28702971/history-of-venous-leg-ulcers
#15
S Gianfaldoni, U Wollina, J Lotti, R Gianfaldoni, T Lotti, M G Roccia
To retrieve the history of venous ulcers and of skin lesions in general, we must go back to the appearance of human beings on earth. It is interesting to note that cutaneous injuries evolved parallel to human society. An essential first step in the pathogenesis of ulcers was represented by the transition of the quadruped man to Homo Erectus. This condition was characterized by a greater gravitational pressure on the lower limbs, with consequences on the peripheral venous system. Furthermore, human evolution was characterized by an increased risk of traumatic injuries, secondary to his natural need to create fire and hunt (e...
July 13, 2017: Journal of Biological Regulators and Homeostatic Agents
https://www.readbyqxmd.com/read/28702730/compressive-nonlinearity-of-human-hearing-in-sound-spectra-discrimination
#16
O N Milekhina, D I Nechaev, A Ya Supin
In the psychophysical experiments reported here, cochlear compression function was derived by comparing on-frequency and off-frequency masking. The signal was rippled spectrum noise. The ripple density discrimination threshold was measured in the ripple phase reversion test. An increase in masker intensity led to a decrease in a resolvable ripple density threshold. The on-frequency masker level at threshold increased proportionally to the signal intensity. The off-frequency masker level at threshold also increased proportionally to the signal at signal intensity levels below 50 dB, whereas at signal levels above 60 dB SPL, the ratio of the masker level at threshold gradient to signal level gradient was 1 : 5 dB/dB, revealing cochlear compression...
May 2017: Doklady Biological Sciences: Proceedings of the Academy of Sciences of the USSR, Biological Sciences Sections
https://www.readbyqxmd.com/read/28702393/the-arcade-of-struthers-an-anatomical-study-and-clinical-implications
#17
Edie Benedito Caetano, João José Sabongi Neto, Luiz Angelo Vieira, Maurício Ferreira Caetano
OBJECTIVE: To determine the frequency and features of the arcade of Struthers, and to assess its clinical implication in ulnar nerve compression. METHOD: Forty arms from 26 cadaver specimens were dissected in the Anatomy Laboratory of this institution. The extension of the arcade, distance from the medial epicondyle, and relation with ulnar nerve were recorded. RESULTS: The arcade of Struthers was identified in 40 dissected arms (100%). In 29 (72...
May 2017: Revista Brasileira de Ortopedia
https://www.readbyqxmd.com/read/28692977/low-rank-matrix-completion-to-reconstruct-incomplete-rendering-images
#18
Ping Liu, John P Lewis, Taehyun Rhee
Path tracing provides photo-realistic rendering in many applications but intermediate previsualization often suffers from distracting noise. Since the fundamental underlying problem is insufficient samples, we exploit the coherence of the visual signal to reconstruct missing samples, using a low-rank matrix completion framework. We present novel methods to construct low rank matrices for incomplete images including missing pixel, missing sub-pixel, and multi-frame scenarios. A convolutional neural network provides fast pre-completion for initialising missing values, and subsequent weighted nuclear norm minimisation (WNNM) with a parameter adjustment strategy (PAWNNM) efficiently recovers missing values even in high frequency details...
July 3, 2017: IEEE Transactions on Visualization and Computer Graphics
https://www.readbyqxmd.com/read/28692958/grift-a-device-for-quantifying-physiological-and-pathological-mirror-movements-in-children
#19
E Jaspers, K Klingels, C Simon-Martinez, H Feys, D G Woolley, N Wenderoth
Mirror movements (MM) typically occur during unilateral actions and manifest as involuntary muscle activity of the passive limb, which "mirror" voluntary actions executed by the contralateral homologous body part. They are a normal motor feature in young children and gradually disappear during the first decade of life. In children suffering from neurological disorders, e.g. due to an early brain lesion as in unilateral cerebral palsy, the amplitude and occurrence of MM has been proposed to yield relevant information for diagnosis and therapy...
July 5, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/28689485/therapeutic-ultrasound-after-sciatic-nerve-compression-of-wistar-rats
#20
Gladson Ricardo Flor Bertolini, Jhenifer Karvat, Camila Mayumi Martin Kakihata, Lucinéia de Fátima Chasko Ribeiro, Rose Meire Costa Brancalhão
OBJECTIVES: The present study analyzed the effect of therapy with therapeutic ultrasound on the sciatic nerve after compression injury, comparing two similar doses of SATA. METHODS: In total, 32 Wistar rats were used, divided into the following groups: CG - control; IG - compression injury of the sciatic nerve; IGCU - injury and continuous ultrasound; and IGPU - injury and 20% pulsed ultrasound. The treatment with ultrasound started on the 3rd postoperative day, with a frequency of 1 MHz, 0...
July 8, 2017: Neurological Research
keyword
keyword
90413
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"