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The purpose of the current study was to develop a deep learning technique called Golden-angle RAdial Sparse Parallel Network (GRASPnet) for fast reconstruction of dynamic contrast-enhanced 4D MRI acquired with golden-angle radial k-space trajectories. GRASPnet operates in the image-time space and does not use explicit data consistency to minimize the reconstruction time. Three different network architectures were developed: (1) GRASPnet-2D: 2D convolutional kernels (x,y) and coil and contrast dimensions collapsed into a single combined dimension; (2) GRASPnet-3D: 3D kernels (x,y,t); and (3) GRASPnet-2D + time: two 3D kernels to first exploit spatial correlations (x,y,1) followed by temporal correlations (1,1,t). The networks were trained using iterative GRASP reconstruction as the reference. Free-breathing 3D abdominal imaging with contrast injection was performed on 33 patients with liver lesions using a T1-weighted golden-angle stack-of-stars pulse sequence. Ten datasets were used for testing. The three GRASPnet architectures were compared with iterative GRASP results using quantitative and qualitative analysis, including impressions from two body radiologists. The three GRASPnet techniques reduced the reconstruction time to about 13 s with similar results with respect to iterative GRASP. Among the GRASPnet techniques, GRASPnet-2D + time compared favorably in the quantitative analysis. Spatiotemporal deep learning enables reconstruction of dynamic 4D contrast-enhanced images in a few seconds, which would facilitate translation to clinical practice of compressed sensing methods that are currently limited by long reconstruction times., (© 2022 John Wiley & Sons Ltd.)

Background: The distal radial artery (DRA) access is an alternative to the conventional radial artery (CRA) access for coronary angiography and interventions and appears to be associated with reduced incidence of certain outcomes., Methods: A systematic review was performed to evaluate differences between DRA versus CRA access for coronary angiography and/or interventions. Following preferred reporting items for systematic review and meta-analysis-protocols guidelines, two reviewers independently selected studies published in the electronic databases (MEDLINE, EMBASE, SCOPUS, CENTRAL) from inception to October 10, 2022, followed by data extraction, meta-analysis, and quality assessment., Results: The final review included 28 studies with (total: 9151 patients [DRA: 4474; CRA: 4677]). Compared with CRA, DRA access was found to be associated with a shorter time to achieve hemostasis (mean difference, MD: -32.49 [95% confidence interval, CI: -65.53, -2.46], p < 0.00001), and reduced incidence of radial artery occlusion (RAO) (risk ratio, RR: 0.38 [95% CI: 0.25, 0.57], p < 0.00001), any bleeding (RR: 0.44 [95% CI: 0.22, 0.86], p = 0.02), and pseudoaneurysm (RR: 0.41 [95% CI: 0.18, 0.99], p = 0.05). However, DRA access has increased access time (MD: 0.31 [95% CI: -0.09, 0.71], p < 0.00001) and crossover rates (RR: 2.75 [95% CI: 1.70, 4.44], p < 0.00001). There were no statistically significant differences in other technical aspects and complications., Conclusion: DRA access is a safe and feasible approach for coronary angiography and interventions. Compared to CRA, DRA provides a shorter hemostasis time, lower incidence of RAO, any bleeding, and pseudoaneurysm, and is associated with increased access time and crossover rates., (© 2023 Wiley Periodicals LLC.)

Objectives: Both radial and focused types of extracorporeal shock wave therapy (ESWT) have been used in patients with plantar calcaneal spur (PCS). However, no study has yet addressed the comparative effects of these treatments on the condition. Considering radial and focused waves are different from each other, their effectiveness may also be different in clinical practice. The aim of this study was to compare the effects of radial and focused types of ESWT on PCS., Methods: Ninety-nine patients with plantar calcaneal spur were randomised into three groups according to ESWT types: focused, radial, and sham. ESWT was applied as three sessions, with 2-4 days intervals (excluding weekends). All patients were evaluated at baseline (week 0) and weeks 1, 5, and 13. The Foot Function Index (FFI) scores were used as outcome measures., Results: Compared with baseline (week 0), at the end of treatment (week 1) and at the follow-up periods (weeks 5, and 13) the FFI scores were significantly reduced in both focused and radial ESWT groups (for all, p < 0.001). When considering the change in data from baseline to follow-up periods (weeks 5, and 13), both focused and radial ESWT groups were significantly superior to the sham group in the all outcome measures (for all, p < 0.05). Importantly, the radial group was significantly superior to focused group based on the changes in the FFI scores (for all, p < 0.05)., Conclusion: Both focused ESWT and radial ESWT are effective in plantar calcaneal spur. When considering the degree and continuity of the positive effects, radial ESWT is superior to focused ESWT in plantar calcaneal spur.

Purpose: To explore a fetal 3D cardiovascular cine acquisition using a radial image acquisition and compressed-sensing reconstruction and compare image quality and scan time with conventional multislice 2D imaging., Methods: Volumetric fetal cardiac data were acquired in 26 volunteers using a radial 3D balanced SSFP pulse sequence. Cardiac gating was performed using a Doppler ultrasound device. Images were reconstructed using a parallel-imaging and compressed-sensing algorithm. Multiplanar reformatting to standard cardiac views was performed before image analysis. Clinical 2D images were used for comparison. Qualitative and quantitative image evaluation were performed by two experienced observers (scale: 1-4). Volumes, mass, and function were assessed., Results: Average scan time for the 3D imaging was 6 min, including one localizer. A 2D imaging stack covering the entire heart including localizer sequences took at least 6.5 min, depending on planning complexity. The 3D acquisition was successful in 7 of 26 subjects (27%). Overall image contrast and perceived resolution were lower in the 3D images. Nonetheless, the 3D images had, on average, a moderate cardiac diagnostic quality (median [range]: 3 [1-4]). Standard clinical 2D acquisitions had a high cardiac diagnostic quality (median [range]: 4 [3, 4]). Cardiac measurements were not different between 2D and 3D images (all p > 0.16)., Conclusion: The presented free-breathing whole-heart fetal 3D radial cine MRI acquisition and reconstruction method enables retrospective visualization of all cardiac views while keeping examination times short. This proof-of-concept work produced images with diagnostic quality, while at the same time reducing the planning complexity to a single localizer., (© 2022 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.)

Objective . To develop a respiratory motion-resolved four-dimensional (4D) magnetic resonance imaging (MRI) technique with high-isotropic-resolution (1.1 mm) using 3D radial sampling, camera-based respiratory motion sensing, and temporal compressed sensing reconstruction for lung cancer imaging. Approach . Free-breathing half- and full-spoke 3D golden-angle radial acquisitions were performed on eight healthy volunteers and eight patients with lung tumors of varying size. A back-and-forth k-space ordering between consecutive interleaves of the 3D radial acquisition was performed to minimize eddy current-related artifacts. Data were sorted into respiratory motion states using camera-based motion navigation and 4D images were reconstructed using temporal compressed sensing to reduce scan time. Normalized sharpness indices of the diaphragm, apparent signal-to-noise ratio (aSNR) and contrast-to-noise ratio (CNR) of the lung tumor (patients only), liver, and aortic arch were compared between half- and full-spoke 4D MRI images to evaluate the impact of respiratory motion and image contrast on 4D MRI image quality. Respiration-induced changes in lung volumes and center of mass shifts were compared between half- and full-spoke 4D MRI measurements. In addition, the motion measurements from 4D MRI and the same-day 4D CT were presented in one of the lung tumor patients. Main results . Half-spoke 4D MRI provides better visualization of the lung parenchyma, while full-spoke 4D MRI presents sharper diaphragm images and higher aSNR and CNR in the lung tumor, liver, and aortic arch. Lung volume changes and center of mass shifts measured by half- and full-spoke 4D MRI were not statistically different. For the patient with 4D MRI and same-day 4D CT, lung volume changes and center of mass shifts were generally comparable. Significance . This work demonstrates the feasibility of a motion-resolved 4D MRI technique with high-isotropic-resolution using 3D radial acquisition, camera-based respiratory motion sensing, and temporal compressed sensing reconstruction for treatment planning and motion monitoring in radiotherapy of lung cancer., (Creative Commons Attribution license.)

Background The effectiveness of vascular closure devices (VCDs) to reduce bleeding after transfemoral percutaneous coronary intervention remains unsettled. Methods and Results Participants in the REGULATE-PCI (Effect of the REG1 anticoagulation system versus bivalirudin on outcomes after percutaneous coronary intervention) trial who underwent transfemoral percutaneous coronary intervention with VCD implantation were compared with those who underwent manual compression. The primary effectiveness end point was type 2, 3, or 5 Bleeding Academic Research Consortium access site bleeding at day 3. Univariate and multivariate analyses were adjusted by the inverse probability weighting method using propensity score. Time to hemostasis and time to ambulation were compared between groups. Of the 1580 patients who underwent transfemoral percutaneous coronary intervention, 1004 (63.5%) underwent VCD implantation and 576 (36.5%) had manual compression. The primary effectiveness end point occurred in 64 (6.4%) participants in the VCD group and in 38 (6.6%) participants in the manual compression group (inverse probability weighting-adjusted odds ratio, 1.02 [95% CI, 0.77-1.36]; P =0.89). There were statistically significant 2-way interactions between VCD use and female sex, chronic kidney disease, and use of high-potency P2Y12 inhibition (ticagrelor or prasugrel) ( P <0.05 for all) with less bleeding with VCD use in these high-risk subgroups. Median time to hemostasis and time to ambulation were shorter in the VCD versus the manual compression group ( P <0.01 for both). Conclusions Following transfemoral percutaneous coronary intervention, VCD use is associated with a shorter time to hemostasis and time to ambulation but not less bleeding. Further study of patients with high-bleeding risk is required, including women, patients with chronic kidney disease, and those using high-potency P2Y12 inhibitors. Registration URL: https://clinicaltrials.gov/ct2/show/NCT01848106; Unique identifier: NCT01848106.

Three common symmetries exist in the natural visual world: (i) mirror symmetry, i.e., reflections around a vertical axis, (ii) radial symmetry, i.e., rotations around a point, and (iii) translational symmetry, i.e., shifted repetitions. Are these processed by a common class of visual mechanism? Using stimuli comprising arrays of Gaussian blobs we examined this question using a visual search protocol in which observers located a single symmetric target patch among varying numbers of random-blob distractor patches. The testing protocol used a blocked present/absent task and both search times and accuracy were recorded. Search times for mirror and radial symmetry increased significantly with the number of distractors, as did translational-symmetry patterns containing few repetitions. However translational-symmetry patterns with four repeating sectors produced search slopes close to zero. Fourier analysis revealed that, as with images of natural scenes, the structural information in both mirror- and radial-symmetric patterns is carried by the phase spectrum. However, for translational patterns with four repeating sectors, the amplitude spectrum appears to capture the structure, consistent with previous analyses of texture regularity. Modeling revealed that while the mirror and radial patterns produced an approximately Gaussian-shaped energy response profile as a function of spatial frequency, the translational pattern profiles contained a distinctive spike, the magnitude of which increased with the number of repeating sectors. We propose distinct mechanisms for the detection of different symmetry types: a mechanism that encodes local positional information to detect mirror- and radial-symmetric patterns and a mechanism that computes energy in narrowband filters for the detection of translational symmetry containing many sectors., (© 2022. The Author(s).)

Background The transradial route has become the primary approach for coronary angiography with the presence of radial artery anomalies found to be 10–20%. There has been limited study on the influence of these anomalies on procedural pain. Our aims were to determine local prevalence of the high radial origin (HRO) anatomical variant; to investigate factors influencing transradial procedural pain; and to determine if HRO specifically was associated with increased pain. Methods Radial artery anatomy was characterized by arteriography in sequential patients undergoing angiography. Patients were asked to mark their perceived procedural pain on a visual analog scale, which was converted to a pain score. Results 382 patients were enrolled, 5 were excluded. There were 259 males (68.7%) and 118 females (31.3%). HRO was present in 51 patients (13.5%). Overall mean pain score was 2.6 (SD 2.5). HRO was associated with a higher mean pain score than normal anatomy (3.3 (SD 2.9) vs. 2.4 (SD 2.4) p = 0.027). HRO was not associated with increased procedural failure, screening time or procedure time. When pain score was dichotomized into mild pain (< 4.0) and moderate-to-severe pain (≥ 4.0), HRO was associated with almost double the frequency of moderate-to-severe pain (37.2% vs. 21.1%, p = 0.012). Using a logistic regression model, only female gender, younger age and HRO remained significant predictors of moderate-to-severe pain. Conclusions There was significantly increased pain in patients with HRO without increased procedure/screening time or procedural failure. Female gender and younger age were also found to be significant predictors of increased pain. [ABSTRACT FROM AUTHOR]

Purpose To estimate k-space trajectory errors in non-Cartesian acquisitions and reconstruct distortion-free images, without trajectory measurements or gradient calibrations. Theory and Methods The Trajectory Auto-Corrected image Reconstruction method jointly estimates k-space trajectory errors and images, based on SENSE and SPIRiT parallel imaging reconstruction. The underlying idea is that parallel imaging and oversampling in the center of k-space provides data redundancy that can be exploited to simultaneously reconstruct images and correct trajectory errors. Trajectory errors are represented as weighted sums of trajectory-dependent error basis functions, the coefficients of which are estimated using gradient-based optimization. Results Trajectory Auto-Corrected image Reconstruction was applied to reconstruct images and errors in golden angle radial, center-out radial, and spiral in vivo 7 Tesla brain acquisitions in five subjects. Compared to reconstructions using nominal trajectories, Trajectory auto-corrected image reconstructions contained considerably less blurring and streaking and were of similar quality to images reconstructed using measured k-space trajectories in the center-out radial and spiral cases. Reconstruction cost function reductions and improvements in normalized image gradient squared were also similar to those for images reconstructed using measured trajectories. Conclusion Trajectory Auto-Corrected image Reconstruction enables non-Cartesian image reconstructions free from trajectory errors without the need for separate gradient calibrations or trajectory measurements. Magn Reson Med 76:757-768, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In this article, a decentralized droop control scheme is proposed based on traditional current-voltage type droop control. This approach not only can eliminate the deviation of DC output voltage, it can also adjust the sharing accuracy of DC output current in multi-terminal high voltage DC systems. The averaging DC output voltage and current of two neighboring converters are employed to reduce the complexity of the communication networks, which include both radial and mesh configurations. In order to demonstrate the stability of the proposed method, the Pi-section line model of DC cable is used to simplify the model of multi-terminal high voltage DC networks, and the impact of varying DC cable impedance parameters and low bandwidth communication delay time are analyzed in detail. Finally, simulation results derived from a multi-terminal high voltage DC system is implemented in MATLAB/SIMULI-NK to verify the proposed approach. [ABSTRACT FROM PUBLISHER]

The pathogenesis of congenital radial head dislocation/subluxation is unknown and has not been previously investigated. In this review, we explore the pathogenesis and define five different primary insults: collagen abnormalities, abnormal endochondral ossification of the developing growth plate, abnormalities of forearm ossification outside the growth plate, disproportionate growth of the radius and ulna, and altered HOX D expression/activity. Finally, the clinical relevance of our review is discussed. [ABSTRACT FROM AUTHOR]

No consensus exists about which coronary artery should be firstly catheterized in primary PCIs. Initial catheterization of the 'culprit artery' could reduce reperfusion time. However, complete knowledge of coronary anatomy could modify revascularization strategy. The objective of the study was to analyze this issue in ST-elevation myocardial infarction patients undergoing primary PCI. PCIs were performed in 384 consecutive patients. Choice of ipsilateral approach (IA): starting with a guiding catheter for the angiography and PCI of the 'culprit artery', or contralateral approach (CA): starting with a diagnostic catheter for the 'non-culprit artery' and completing the angiography and PCI of the culprit with a guiding catheter was left to the operator. Differences between two approaches regarding reperfusion time, acute events or revascularization strategies were analyzed. There were no differences between two approaches regarding reperfusion time or clinical events. When the left coronary artery was responsible, IA was more frequent (76.4 vs 22.6 %), but when it was the right coronary artery, CA was preferred (20 vs 80 %); p < 0.0001. With CA, bare metal stents (BMS) were more used than drug eluting (DES) (60.8 vs 39.2 %) inversely than with IA (BMS 41.3 vs DES 59.7 %; p < 0.0001). With CA there were more patients with left main or multivessel disease in which revascularization was completed with non-urgent surgery (4.13 vs 2.4 %, p < 0.0001). Initial CA does not involve higher reperfusion time. Furthermore, overall knowledge of coronary anatomy offers more options in revascularization strategy and may imply a change in management. Despite the need to individualize each case, contralateral approach may be the first option with the exception of unstable patients. [ABSTRACT FROM AUTHOR]

Approaches to the quantification of the vertical translocation rate of soil solid-phase material by the magnetic tracer method have been developed; the tracer penetration depth and rate have been determined, as well as the radial distribution of the tracer in chernozems (Chernozems) and dark gray forest soils (Luvisols) of Belgorod oblast under natural steppe and forest vegetation and in arable lands under agricultural use of different durations. It has been found that the penetration depth of spherical magnetic particles (SMPs) during their 150-year-occurrence in soils of a forest plot is 68 cm under forest, 58 cm on a 100-year old plowland, and only 49 cm on a 150-year-old plowland. In the chernozems of the steppe plot, the penetration depth of SMPs exceeds the studied depth of 70 cm both under natural vegetation and on the plowlands. The penetration rates of SMPs deep into the soil vary significantly among the key plots: 0.92-1.32 mm/year on the forest plot and 1.47-1.63 mm/year on the steppe plot, probably because of the more active recent turbation activity of soil animals. [ABSTRACT FROM AUTHOR]

The present study has been carried out on the carpal bones of Indian blackbuck. The carpal bones consisted of six short bones arranged in two transverse rows one above the other. The bones of the proximal row from medial to lateral were: radial carpal or scaphoid, intermediate carpal or semilunar, ulnar carpal or cuneiform and accessory carpal or pisiform. The bones of the distal row were second and third fused carpal or os magnum and fourth carpal or unciform. The radial carpal bone was the medial-most of the proximal row and presented six surfaces. The intermediate carpal bone was wedge shaped, being constricted in middle and wide in front. The ulnar carpal was outermost irregular bone situated lateral to the intermediate carpal. The accessory carpal was a short, medially curved bone. It was placed behind the ulnar carpal. In the distal row, the fused second and third carpal bone was situated medially and was larger than fourth carpal. The fourth carpal bone was smaller of the two bones of the distal row. It was roughly quadrilateral in outline and decreased in thickness cranio-caudally. [ABSTRACT FROM AUTHOR]

Cell culture in three-dimensional hollow cylindrical porous scaffolds in radial-flow packed-bed bioreactors (rPBBs) has advantages over static culture and axial perfusion bioreactors. Transport models of rPBBs for tissue engineering proposed thus far neglect the effect of the fluid dynamics of the bioreactor void spaces on radial flux maldistribution, although such an effect was proven important for industrial reactors. In this paper, a two-dimensional axisymmetric model is proposed for steady-state momentum transport in the three compartments of rPBBs under conditions and for construct permeability typical of tissue engineering applications. Transport in the inner hollow cavity and outer peripheral annulus is described according to Navier–Stokes equations, while Darcy–Brinkman equation is used for transport across the annular construct. Model predictions were qualitatively validated against literature data. Effects of the performance-determining dimensionless groups on radial flux distribution along the bioreactor length were investigated, and a criterion was proposed to design and operate rPBBs in which radial fluxes are uniformly distributed along the bioreactor length under conditions typical of tissue engineering. Bioreactor designs and operation meeting the criterion will avoid non-uniform development of tissue structure and functional properties. [ABSTRACT FROM AUTHOR]

Wood shrinks anisotropically as it loses hygroscopic moisture. While longitudinal shrinkage (parallel to the grain) is nearly negligible in normal wood, transverse shrinkage (across the grain) is significant and characterized as tangential and radial shrinkage. The application of average tangential shrinkage values to a rectangular cross section results in errors, especially for boards cut from near the center of the log. In addition, using a Cartesian coordinate system to calculate shrinkage cannot provide an estimate of cup. Calculating shrinkage and cup deformation using a previously developed model, this Excel model can provide a more realistic image of the final cross section and a more accurate estimate of shrinkage. The model is dependent on wood species, initial and final moisture contents, and location of the board within the log. This paper describes and illustrates uses of the model. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the late-term changes in radial artery luminal diameter (RAD) and vasodilatation response following transradial catheterization (TRC). TRC-inducing trauma to radial artery intima may trigger chronic phase vascular changes and lead to anatomical and functional impairment. There is controversial data whether the impairment persists or repairs later. Fifty-six consecutive patients undergoing TRC were enrolled prospectively. Baseline RAD, flow-mediated dilatation (FMD) and nitroglycerin-mediated dilatation (NMD) of the radial artery at the access site were measured before TRC by high-resolution ultrasound. Six months later; RAD, FMD and NMD were measured again at the same access site. RAD at the sixth month was reduced compared with pre-procedural measurements (2.85 ± 0.44 versus 2.74 ± 0.42 mm, p = 0.0001).The average FMD decreased to 5.66 ± 5.87 %, which was significantly lower than the observed pre-procedural FMD (9.45 ± 5.01 %) 6 months after TRC ( p = 0.0001). Likewise, the average NMD at the sixth month was reduced compared with pre-procedural NMD (9.52 ± 6.77 versus 6.64 ± 6.51 %, p = 0.018). Logistic regression analysis indicated that pre-procedural radial artery diameter to sheath size ratio was the independent predictor of NMD reduction (95 % confidence interval, β = −9.74, p = 0.024). TRC may lead to a significant luminal diameter reduction and impairment of vasodilatation response in the radial artery at late term. [ABSTRACT FROM AUTHOR]

Background Advantages of radial access over brachial/axillary or femoral access have been well described for several decades and include decreased cost, patient preference, and decreased major access site complications. Despite these advantages, radial access is rarely employed or even considered for neurointerventional procedures. This attitude should be reconsidered given several recent large, randomized, controlled trials from the cardiovascular literature proving that radial access is associated with statistically lower costs, decreased incidence of myocardial infarctions, strokes, and even decreased mortality. Radial access is now considered the standard of care for percutaneous coronary interventions in most US centers. Although radial access has been described for neurovascular procedures in the past, overall experience is limited. The two major challenges are the unique anatomy required to access the cerebral vasculature given very acute angles between the arm and craniocervical vessels and limitations in available technology. Methods We present a simplified approach to radial access for cerebrovascular procedures and provide a concise step-by-step approach for patient selection, ultrasound-guided single-wall access, recommended catheters/wires, and review of patent hemostasis. Additionally, we present a complex cerebrovascular intervention in which standard femoral access was unsuccessful, while radial access was quickly achieved to highlight the importance of familiarity with the radial approach for all neurointerventionalists. Results We have found that the learning curve is not too steep and that the radial access approach can be adopted smoothly for a large percentage of diagnostic and interventional neuroradiologic procedures. Conclusions Radial access should be considered in all patients undergoing a cerebrovascular procedure. [ABSTRACT FROM AUTHOR]

Objective To ascertain the impact of definition and diagnostic criteria on sural sparing in Guillain–Barré syndrome (GBS). Methods We retrospectively reviewed records of 78 consecutive patients with GBS from Birmingham, UK (2001–2012) studied within 21 days post-onset. Different criteria were initially used for subtype classification. Sural sparing was subsequently ascertained using historical/recent definitions. Results With Hadden et al.’s criteria, “absent median present sural” and “absent median normal sural” patterns offered sensitivities of 21.7% and 15.2% respectively for AIDP, with specificities of 100% versus axonal GBS. Present sural with two abnormal upper limb responses had a sensitivity of 19.1% and 100% specificity. “Abnormal radial present sural” and “abnormal radial normal sural” patterns had sensitivities of 18.9% and 16.2% and specificity of 100%. With newly-proposed criteria ( Rajabally et al., 2015 ), “absent median present sural” and “absent median normal sural” patterns offered sensitivities of 27.8% and 19.4% respectively, with specificity of 100%. Ulnar patterns were unhelpful with both criteria. Other patterns had suboptimal specificity. Conclusion Although of low sensitivity, sural sparing defined by absent median/present sural patterns, is specific of AIDP versus axonal GBS, irrespective of criteria. Significance Sural sparing is definition and criteria-dependent in GBS but is specific of AIDP with historical definitions, regardless of criteria. [ABSTRACT FROM AUTHOR]

Purpose In radial imaging, projections may become 'miscentered' due to gradient errors such as delays and eddy currents. These errors may result in image artifacts and can disrupt the reliability of direct current (DC) navigation. The proposed parallel imaging-based technique retrospectively estimates trajectory error from miscentered radial data without extra acquisitions, hardware, or sequence modification. Theory and Methods After phase correction, self-calibrated GRAPPA operator gridding (GROG) weights are iteratively applied to shift-miscentered projections toward the center of k-space. A search algorithm identifies the shift that aligns the peak k-space signals by maximizing the sum-of-squares DC signal estimate of each projection. The algorithm returns a trajectory estimate and a corrected radial k-space signal. Results Data from a spherical phantom, the head, and the heart demonstrate that image reconstruction with the estimated trajectory restores image quality and reduces artifacts such as streaks and signal voids. The DC signal level is increased and variability is reduced. Conclusion Retrospective phase correction and iterative application of GROG can be used to successfully estimate the trajectory error in two-dimensional radial acquisitions for improved image reconstruction without requiring extra data acquisition or sequence modification. Magn Reson Med 75:883-896, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Nanowires have the potential to play an important role for next-generation light-emitting diodes. In this work, we present a growth scheme for radial nanowire quantum-well structures in the AlGaInP material system using a GaInP nanowire core as a template for radial growth with GaInP as the active layer for emission and AlGaInP as charge carrier barriers. The different layers were analyzed by X-ray diffraction to ensure lattice-matched radial structures. Furthermore, we evaluated the material composition and heterojunction interface sharpness by scanning transmission electron microscopy energy dispersive X-ray spectroscopy. The electro-optical properties were investigated by injection luminescence measurements. The presented results can be a valuable track toward radial nanowire light-emitting diodes in the AlGaInP material system in the red/orange/yellow color spectrum. [ABSTRACT FROM AUTHOR]

In this article we prove the existence of an infinite number of radial solutions of Δ (u) + f (u) = 0 with prescribed number of zeros on the exterior of the ball of radius R > 0 centered at the origin in R N where f is odd with f < 0 on (0,β), f > 0 on (β, ∞) where β > 0. [ABSTRACT FROM AUTHOR]

Purpose: To quantify the accuracy of three-dimensional (3D) radial arterial spin labeled (ASL) magnetic resonance angiography (MRA) using vascular models of carotid stenosis. Methods: Eight vascular models were imaged at 1.5 Tesla using pulsatile flow waveforms at rates found in the internal carotid arteries (100-400 mL/min). The impacts of the 3D ASL imaging readout (fast low angle shot (FLASH) versus balanced steady-state free precession (bSSFP)), ultrashort echo time imaging using a pointwise encoding time reduction with radial acquisition (PETRA), and model stenosis severity on the accuracy of vascular model display at the location of stenosis were quantified. Accuracy was computed vis-a-vis a reference bSSFP volume acquired under no flow. Comparisons were made with standard-of-care contrast-enhanced MRA (CEMRA) and Cartesian time-of-flight (TOF) MRA protocols. Results: For 50% and 70% stenoses, CEMRA was most accurate (respective accuracies of 81.7% and 78.6%), followed by ASL FLASH (75.7% and 71.8%), ASL PETRA (69.6% and 70.6%), 3D TOF (66.6% and 57.1%), ASL bSSFP (68.7% and 51.2%), and 2D TOF (65.1% and 50.6%). Conclusion: Flow phantom imaging studies show that ASL MRA can improve the display of hemodynamically significant carotid arterial stenosis compared with TOF MRA, with FLASH and ultrashort echo time readouts being most accurate. [ABSTRACT FROM AUTHOR]

Ultrasonic pre-treatment of small and pressure saturated Douglas-fir heartwood specimens at 20 kHz fixed frequency with an acoustic horn resulted in increased specific permeability coefficient in both radial and tangential directions. Statistical analysis revealed that there was a high correlation between ultrasonic treatment time and specific permeability coefficient. Improvement rate of permeability in both radial and tangential directions was nearly the same regardless of treatment time.

Résumé L’observation d’une patiente obèse, admise pour la prise en charge d’un syndrome coronaire aigu ST+ en angioplastie primaire, nous permet, à partir des résultats des publications récentes, études randomisées et registres, de rappeler les avantages de la voie radiale dans ce type d’indication en termes de réduction d’évènements majeurs, y compris de réduction de la mortalité. Nous discutons les éléments de réticence à l’utilisation de cette voie d’abord dont seule l’expérience et l’utilisation quotidienne permettront de placer cette voie d’abord comme celle devant s’imposer par défaut dans les SCA ST+. This overweight woman's case, who underwent a primary coronary intervention for STEMI, reminds us how much the trans-radial angioplasty is interesting in this particular case leaning on the recent literature, randomized trials and registries, in terms of major adverse events reduction including mortality. We are going to debate about hesitation of using radial approach whose only everyday's practising could make this approach a STEMI one. [ABSTRACT FROM AUTHOR]

Objective: We aimed to investigate the optimal cutoff value of circumferential resection margin (CRM) of esophageal squamous cell carcinoma (ESCC) in patients who underwent radical esophagectomy. Background: Tumor involvement of a CRM in ESCC has not been clearly defined. Methods: We reviewed 479 pT3 ESCC patients to find the optimal cutoff point of distance from CRM in addition to 0mm for discriminating survival time. Results: The partitions at and near the 500mm distance from CRM generated the largest log-rank statistics (P=0.0086). Therefore, we added 500mm as an additional cutoff value for a positive CRM. Compared to patients with CRM greater than 500mm, patients with CRM 0mm showed worse overall survival (P<0.001) and progression-free survival (P<0.001), followed by patients with 0 to 500mm (P=0.008 and 0.066, respectively). In multivariable analyses, overall survival differences remained significant [0 500mm, hazards ratio (HR)=1.875, 97.5% CI: 1.243-2.829, P=0.002; CRM=0mm vs CRM > 500mm, HR=2.666, 97.5% CI: 1.745-4.076, P<0.001]. In comparison of criteria from the College of American Pathologists, the Royal College of Pathologists, and this study, HRs of positive CRM (95% CI, P-value) were 1.969 (1.501-2.584, P<0.001), 1.384 (1.039-1.844, P=0.027), and 1.696 (1.342-2.143, P<0.001), respectively. Conclusions: In patients with ESCC, we developed new, 3-tiered CRM criteria providing more detailed prognostic information than the 2-tiered criteria. [ABSTRACT FROM AUTHOR]

The feasibility and safety of transradial coronary intervention was demonstrated soon after the description of the transfemoral approach, despite which the use of the femoral artery still dominates in acute coronary syndrome intervention. The advantages of using the radial artery are virtual elimination of access site complications and an important reduction in bleeding, both of which are of utmost importance to the patient with myocardial infarction. Randomised controlled trials have now documented what seems inherent; that transradial intervention should bring with it an advantage in terms of morbidity and mortality in this cohort. The potential disadvantages in terms of speed of procedure and radiation exposure are negated by operator experience. Registries have illustrated that conversion on a large scale from the femoral to the transradial approach is safe and saves lives, most convincingly so in acute coronary syndrome intervention. This review discusses the potential benefits and risks of the alternative access sites in acute patients and explores how these are borne out in the published data. [ABSTRACT FROM AUTHOR]

In this paper we prove the existence of an infinite number of radial solutions of Δu + ƒ (u) = 0 on the exterior of the ball of radius R > 0 centered at the origin and f is odd with f < 0 on (0, β), fƒ> 0 on (β, δ), and ƒ = 0 for u > δ. The primitive F(u) = ʃ0u ƒ (t) dt has a "hilltop" at u = δ which allows one to use the shooting method to prove the existence of solutions. [ABSTRACT FROM AUTHOR]

Purpose Targeted muscle reinnervation (TMR) offers enhanced prosthetic use by harnessing additional neural control from unused nerves in the amputated limb. The purpose of this study was to document the location and number of motor end plates to each muscle commonly used in TMR in the brachium relative to proximally based bony landmarks. Methods We dissected 18 matched upper limbs (9 fresh-frozen cadavers). The locations of each of the nerves’ muscular insertions into the medial biceps and brachialis were measured relative to the anterolateral tip of the acromion. The terminal branches to the lateral triceps were measured relative to the posterolateral tip of the acromion. Both the number of branches and the location of the muscular insertions were documented. Common descriptive statistics were used to describe the data. Results There was a median of 2 branches to the medial biceps located 19.6 cm from the anterolateral tip of the acromion (range, 15–25 cm). There was a median of 3.5 branches to the brachialis located 24.2 cm from the anterolateral tip of the acromion (range, 19–27.5 cm). There was a median of 2.5 branches to the lateral triceps located 21.6 cm from the posterolateral tip of the acromion (range, 11–29 cm). The mean distances to the primary branch muscle and the number of smaller branches were not significantly different when compared by sex or side. Conclusions Motor points for the medial biceps, brachialis, and lateral triceps can be identified reliably using proximal landmarks in targeted muscle reinnervation. Clinical relevance The data obtained from this study may assist the surgeon in localizing the nerve branches and muscular insertions for the commonly used muscles for TMR of the brachium. [ABSTRACT FROM AUTHOR]

Purpose To test the hypothesis that both coronary anatomy and ventricular function can be assessed simultaneously using a single four-dimensional (4D) acquisition. Methods A free-running 4D whole-heart self-navigated acquisition incorporating a golden angle radial trajectory was implemented and tested in vivo in nine healthy adult human subjects. Coronary magnetic resonance angiography (MRA) datasets with retrospective selection of acquisition window width and position were extracted and quantitatively compared with baseline self-navigated electrocardiography (ECG) -triggered coronary MRA. From the 4D datasets, the left-ventricular end-systolic, end-diastolic volumes (ESV & EDV) and ejection fraction (EF) were computed and compared with values obtained from conventional 2D cine images. Results The 4D datasets enabled dynamic assessment of the whole heart with isotropic spatial resolution of 1.15 mm3. Coronary artery image quality was very similar to that of the ECG-triggered baseline scan despite some SNR penalty. A good agreement between 4D and 2D cine imaging was found for EDV, ESV, and EF. Conclusion The hypothesis that both coronary anatomy and ventricular function can be assessed simultaneously in vivo has been tested positive. Retrospective and flexible acquisition window selection allows to best visualize each coronary segment at its individual time point of quiescence. Magn Reson Med 74:1306-1316, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Transradial access is becoming the default strategy for routine coronary procedures, but there is still room for improvement. For instance, left radial access is known to offer some advantages for graft cases, less tortuosity, amongst other potential benefits. The downside has been the applicability of this access point on patients with a larger body mass index both from the viewpoint of the patient and the operator. The patient must lay with their arm in a supine position and the operator as a result must stand in a flexed position for an unknown period of time. Additionally, patients with various orthopedic injuries, including frozen shoulders, on may be unable to supinate their wrist for optimal access. One solution to this dilemma is to approach the radial artery from the dorsal aspect of the hand so the wrist can pronate naturally if body habitus requires the arm to be shifted towards the operator. This report outlines the steps and background behind this approach and an educational opportunity for those interested in expanding their access skills. [ABSTRACT FROM AUTHOR]

A radial multiway power divider is used to distribute microwave signals to the next stages located radially around all directions. It has been a challenging task to implement a radial multiway power divider on a planar circuit board without sacrificing the bandwidth performance. In this letter, a radial four-way power divider with the proposed isolation network is presented. The isolation network, composed of several combined RLC and LC networks, plays the crucial role of making the radial layout style easy to realize, and meanwhile improves the output matching and port-to-port isolation. The background principle of the proposed topology and the guideline of designing the isolation network are provided. The fabricated radial four-way power divider results in the measured −20-dB output matching and isolation bandwidths as large as 35% and 65%, respectively, exhibiting the best bandwidth performance among all the published radial power dividers of the same type. [ABSTRACT FROM PUBLISHER]

OBJECTIVE: To evaluate the impact of the use, prior to the procedure, of injectable diltiazem to prevent complications. METHODS: Between September 2000 and July 2001, 50 patients underwent transradial coronary angiography and were randomized to receive placebo (GI) or diltiazem (GII) through a catheter inserted into the radial artery. All patients received isosorbide mononitrate. Ultrasound analyses of the radial artery were performed before examination, 30 minutes afterwards, and 7 days afterwards to evaluate the flow, the diameter, and the artery output. RESULTS: The radial artery diameter of GI was 2.4± 0.5 mm before the procedure and 2.3±0.5 mm after 30 minutes (NS), whereas in GII the diameter was 2.2±0.3 mm before the examination and 2.5±0.4 mm 30 minutes after it (P

The objective of this research was to recognize the hand gestures of Arabic Sign Language (ArSL) words using two depth sensors. The researchers developed a model to examine 143 signs gestured by 10 users for 5 ArSL words (the dataset). The sensors captured depth images of the upper human body, from which 235 angles (features) were extracted for each joint and between each pair of bones. The dataset was divided into a training set (109 observations) and a testing set (34 observations). The support vector machine (SVM) classifier was set using different parameters on the gestured words’ dataset to produce four SVM models, with linear kernel (SVMLD and SVMLT) and radial kernel (SVMRD and SVMRT) functions. The overall identification accuracy for the corresponding words in the training set for the SVMLD, SVMLT, SVMRD, and SVMRT models was 88.92%, 88.92%, 90.88%, and 90.884%, respectively. The accuracy from the testing set for SVMLD, SVMLT, SVMRD, and SVMRT was 97.059%, 97.059%, 94.118%, and 97.059%, respectively. Therefore, since the two kernels in the models were close in performance, it is far more efficient to use the less complex model (linear kernel) set with a default parameter.