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The significant problem of wall slip and shear viscosity of dense suspensions is addressed using steady torsional and capillary flows of a silicone polymer, incorporated with polydisperse particles with low aspect ratios, to achieve a relatively high maximum packing fraction, ϕ m = 0.86. Such a high ϕ m allowed the preparation of well-mixed suspensions with a wide range of solid volume fractions, ϕ , i.e., 0.62 ≤ ϕ ≤ 0.82. It is demonstrated that the characterization of the relative viscosity and yield stresses of the particulate suspensions requires a proper treatment of wall slip effects. The wall slip velocity versus the shear stress relationship is governed by the apparent slip mechanism and is predictable using the shear viscosity of the binder and the thickness of the apparent slip layer. At shear stresses which are significantly above the yield stress, the relative shear viscosity of the suspensions depends solely on ϕ / ϕ m . However, at lower shear stresses that are in the vicinity of the yield stresses, the relative shear viscosity becomes functions of both ϕ / ϕ m and the shear stress. [ABSTRACT FROM AUTHOR]

Abstract Introduction Displacement encoding with stimulated echoes (DENSE) is a phase contrast technique that encodes tissue displacement into phase images, which are typically processed into measures of cardiac function such as strains. For improved signal to noise ratio and spatiotemporal resolution, DENSE is often acquired with a spiral readout using an 11.1 ms readout duration. However, long spiral readout durations are prone to blurring due to common phenomena such as off-resonance and T2* decay, which may alter the resulting quantifications of strain. We hypothesized that longer readout durations would reduce image quality and underestimate cardiac strains at both 3.0 T and 1.5 T and that using short readout durations could overcome these limitations. Material and methods Computational simulations were performed to investigate the relationship between off-resonance and T2* decay, the spiral cine DENSE readout duration, and measured radial and circumferential strain. Five healthy participants subsequently underwent 2D spiral cine DENSE at both 3.0 T and 1.5 T with several different readout durations 11.1 ms and shorter. Pearson correlations were used to assess the relationship between cardiac strains and the spiral readout duration. Results Simulations demonstrated that long readout durations combined with off-resonance and T2* decay yield blurred images and underestimate strains. With the typical 11.1 ms DENSE readout, blurring was present in the anterior and lateral left ventricular segments of participants and was markedly improved with shorter readout durations. Radial and circumferential strains from those segments were significantly correlated with the readout duration. Compared to the 1.9 ms readout, the 11.1 ms readout underestimated radial and circumferential strains in those segments at both field strengths by up to 19.6% and 1.5% (absolute), or 42% and 7% (relative), respectively. Conclusions Blurring is present in spiral cine DENSE images acquired at both 3.0 T and 1.5 T using the typical 11.1 ms readout duration, which yielded substantially reduced radial strains and mildly reduced circumferential strains. Clinical studies using spiral cine DENSE should consider these limitations, while future technical advances may need to leverage accelerated techniques to improve the robustness and accuracy of the DENSE acquisition rather than focusing solely on reduced acquisition time. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to evaluate the effect of full-thickness chondral defects on intratissue deformation patterns and matrix constituents in an experimental model mimicking in vivo cartilage-on-cartilage contact conditions.Design: Pairs of bovine osteochondral explants, in a unique cartilage-on-cartilage model system, were compressed uniaxially by 350 N during 2 s loading and 1.4 s unloading cycles (≈1700 repetitions). Tissue deformations under quasi-steady state load deformation response were measured with displacement encoded imaging with stimulated echoes (DENSE) in a 9.4 T magnetic resonance imaging (MRI) scanner. Pre- and post-loading, T1, T2 and T1ρ relaxation time maps were measured. We analyzed differences in strain patterns and relaxation times between intact cartilage (n = 8) and cartilage in which a full-thickness and critical sized defect was created (n = 8).Results: Under compressive loading, strain magnitudes were elevated at the defect rim, with elevated tensile and compressive principal strains (Δϵmax = 4.2%, P = 0.02; Δϵmin = -4.3%, P = 0.02) and maximum shear strain at the defect rim (Δγmax = 4.4%, P = 0.007). The opposing cartilage showed minimal increase in strain patterns at contact with the defect rim but decreased strains opposing the defect. After defect creation, T1, T2 and T1ρ relaxation times were elevated at the defect rim only. Following loading, the overall relaxations times of the defect tissue and especially at the rim, increased compared to intact cartilage.Conclusions: This study demonstrates that the local biomechanical changes occurring after defect creation may induce tissue damage by increasing shear strains and depletion of cartilage constituents at the defect rim under compressive loading. [ABSTRACT FROM AUTHOR]

Objective: This study aims to characterize the deformations in articular cartilage under compressive loading and link these to changes in the extracellular matrix constituents described by magnetic resonance imaging (MRI) relaxation times in an experimental model mimicking in vivo cartilage-on-cartilage contact.Design: Quantitative MRI images, T1, T2 and T1ρ relaxation times, were acquired at 9.4T from bovine femoral osteochondral explants before and immediately after loading. Two-dimensional intra-tissue displacement and strain fields under cyclic compressive loading (350N) were measured using the displacement encoding with stimulated echoes (DENSE) method. Changes in relaxation times in response to loading were evaluated against the deformation fields.Results: Deformation fields showed consistent patterns among all specimens, with maximal strains at the articular surface that decrease with tissue depth. Axial and transverse strains were maximal around the center of the contact region, whereas shear strains were minimal around the contact center but increased towards contact edges. A decrease in T2 and T1ρ was observed immediately after loading whereas the opposite was observed for T1. No correlations between cartilage deformation patterns and changes in relaxation times were observed.Conclusions: Displacement encoding combined with relaxometry by MRI can noninvasively monitor the cartilage biomechanical and biochemical properties associated with loading. The deformation fields reveal complex patterns reflecting the depth-dependent mechanical properties, but intra-tissue deformation under compressive loading does not correlate with structural and compositional changes. The compacting effect of cyclic compression on the cartilage tissue was revealed by the change in relaxation time immediately after loading. [ABSTRACT FROM AUTHOR]

Membrane distillation (MD) is considered as a key technology for desalination applications. It shows indeed numerous advantages compared to reverse osmosis and other desalination processes (e.g. thermal driving force, no osmotic pressure effect on membrane fluxes). Nevertheless, this technology still presents some issues, most notably due to pore wetting effects. This study proposes the use of a thin, self-standing dense membrane in place of microporous materials as a solution to avoid wetting in MD for water desalination. In a first step, a membrane contactor model is developed based on mass and energy balances and the simulations are validated using experimental results obtained on hollow fiber modules with microporous membranes. A comparative performance analysis is then achieved between a porous and a dense membrane module. A parametric study on the influence of dense membrane thickness and water permeability shows that a two fold increase in water flux, without significant impact on energy efficiency, is potentially achievable with thin and permeable dense materials compared to microporous membranes. Guidelines for the design of high-performance dense membrane modules for MD are finally proposed. [ABSTRACT FROM AUTHOR]

Recently, Konca et al. (2015a) have revisited the space lp of p-summable sequences of real numbers and have shown that this space is actually contained in a weighted inner product space called l²v. In another paper, Konca et al. (2015b) have investigated the space lp to show that it is also contained in a weighted 2-inner product space. In this work, we show in the details that lp is dense in l²v as a normed space, and as a 2-normed space. Further, we prove that l²v is separable and conclude that it is isometric to the completion of lp. [ABSTRACT FROM AUTHOR]

The densest k-subgraph (DkS) problem and its corresponding minimization problem smallest p-edge subgraph (SpES) have come to play a central role in approximation algorithms. This is due both to their practical importance and to their usefulness as a tool for solving and establishing approximation bounds for other problems. These two problems are not well understood, and it is widely believed that they do not admit a subpolynomial approximation ratio (although the best-known hardness results do not rule this out). In this paper we generalize both DkS and SpES from graphs to hypergraphs. We consider the densest k-subhypergraph (DkSH) problem (given a hypergraph (V;E), find a subset W ⊆ V of k vertices so as to maximize the number of hyperedges contained in W), and define the minimum p-union (MpU) problem (given a hypergraph, choose p of the hyperedges so as to minimize the number of vertices in their union). We focus in particular on the case where all hyperedges have size 3, as this is the simplest nongraph setting. For this case we provide an O(n4(4-√3)=13+∊) < O(n0:697831+∊)-approximation (for arbitrary constant ∊ > 0) for DkSH and an O (n2/5)-approximation for MpU. We also give an O(pm)-approximation for MpU in general hypergraphs. Finally, we examine the interesting special case of interval hypergraphs (instances where the vertices are a subset of the natural numbers and the hyperedges are intervals of the line) and prove that both problems admit an exact polynomial-time solution on these instances. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fast and accurate coals and gangues detector named ISNet_CG is proposed. • A light backbone called DSNet is redesigned to improve the recognition rate. • The neck network is optimized to enhance the feature extraction of the targets. • Identify and segment multiple coal and gangue in the image at the pixel level. • Solve the problem of low recognition rate in a complex environment. Coal and gangue intelligent sorting accounts for a vital proportion of modern coal mines, which takes on critical significance in boosting clean coal utilization. Aiming at the problem of low recognition accuracy that arises from the large diversity in particle size of raw coal and the adhesion and half-occlusion between them, A Mask RCNN-based instance segmentation network for coal and gangue image is proposed. First, multi-branch parallel feature extraction bottlenecks are developed to build a lightweight backbone with a mixed attention mechanism and self-correcting convolution incorporated to enhance the feature representation of targets. Subsequently, a necknet is developed, aggregating the context feature information of the backbone from channel and space to enhance the position and boundary information of targets. Lastly, the effectiveness of this method is fully validated by ablation and test experiments using self-built coal and gangue RGB image datasets include varieties of characteristics as input. As indicated by the experimental results, the above-described method is capable of enhancing the segmentation ability of stacked and adhered coal and gangue and reducing the missed detection rate of small targets. ISNet_CG achieves mAP, mIoU, F1-scores, and FPS of 98.0, 96.5, 0.987, and 24.2 FPS, respectively, such that the correct category and location can be provided for coal and gangue in a dense state. [ABSTRACT FROM AUTHOR]

Background: Patients with repaired tetralogy of Fallot (TOF) have progressive, adverse biventricular remodeling, leading to abnormal contractile mechanics. Defining the mechanisms underlying this dysfunction, such as diffuse myocardial fibrosis, may provide insights into poor long-term outcomes. We hypothesized that left ventricular (LV) diffuse fibrosis is related to impaired LV mechanics. Methods: Patients with TOF were evaluated with cardiac magnetic resonance in which modified Look-Locker (MOLLI) T1-mapping and spiral cine Displacement encoding (DENSE) sequences were acquired at three LV short-axis positions. Linear mixed modeling was used to define the association between regional LV mechanics from DENSE based on regional T1-derived diffuse fibrosis measures, such as extracellular volume fraction (ECV). Results: Forty patients (26 ± 11 years) were included. LV ECV was generally within normal range (0.24 ± 0.05). For LV mechanics, peak circumferential strains (-15 ± 3%) and dyssynchrony indices (16 ± 8 ms) were moderately impaired, while peak radial strains (29 ± 8%) were generally normal. After adjusting for patient age, sex, and regional LV differences, ECV was associated with log-adjusted LV dyssynchrony index (β = 0.67) and peak LV radial strain (β = -0.36), but not LV circumferential strain. Moreover, post-contrast T1 was associated with log-adjusted LV diastolic circumferential strain rate (β = 0.37). Conclusions: We observed several moderate associations between measures of fibrosis and impaired mechanics, particularly the LV dyssynchrony index and peak radial strain. Diffuse fibrosis may therefore be a causal factor in some ventricular dysfunction in TOF. [ABSTRACT FROM AUTHOR]

Purpose: To image late mechanical activation and identify effective left-ventricular (LV) pacing sites for cardiac resynchronization therapy (CRT). There is variability in defining mechanical activation time, with some studies using the time to peak strain (TPS) and some using the time to the onset of circumferential shortening (TOS). We developed improved methods for imaging mechanical activation and evaluated them in heart failure (HF) patients undergoing CRT.Materials and Methods: We applied active contours to cine displacement encoding with stimulated echoes (DENSE) strain images to detect TOS. Six healthy volunteers underwent magnetic resonance imaging (MRI) at 1.5T, and 50 patients underwent pre-CRT MRI (strain, scar, volumes) and echocardiography, assessment of the electrical activation time (Q-LV) at the LV pacing site, and echocardiography assessment of LV reverse remodeling 6 months after CRT. TPS at the LV pacing site was also measured by DENSE.Results: The latest TOS was greater in HF patients vs. healthy subjects (112 ± 28 msec vs. 61 ± 7 msec, P < 0.01). The correlation between TOS and Q-LV was strong (r > 0.75; P < 0.001) and better than between TPS and Q-LV (r < 0.62; P ≥ 0.006). Twenty-three of 50 patients had the latest activating segment in a region other than the mid-ventricular lateral wall, the most common site for the CRT LV lead. Using a multivariable model, TOS/QRS was significantly associated with LV reverse remodeling even after adjustment for overall dyssynchrony and scar (P < 0.05), whereas TPS was not (P = 0.49).Conclusion: Late activation by cine DENSE TOS analysis is associated with improved LV reverse remodeling with CRT and deserves further study as a tool to achieve optimal LV lead placement in CRT.Level Of Evidence: 1 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:887-896. [ABSTRACT FROM AUTHOR]

Background: Women with dense mammographic breast density (BD) have a 2-fold increased risk of developing primary breast cancer (BC). The authors hypothesized that dense mammographic BD also is associated with an increased risk of developing contralateral breast cancer (CBC).Methods: Among female patients treated at The University of Texas MD Anderson Cancer Center for sporadic, AJCC stage I to stage III BC between January 1997 and December 2012, the authors identified patients who had developed metachronous CBC (cases) and selected 1:2 matched controls who did not develop CBC using incidence density sampling, matched on attainted age, year of diagnosis, and hormone receptor status of the first BC. Mammographic BD, assessed at the time of first BC diagnosis, was categorized as "nondense" (American College of Radiology breast categories of fatty or scattered density) or "dense" (American College of Radiology categories of heterogeneously dense or extremely dense). Multivariable conditional logistic regression models were used for statistical analysis.Results: A total of 229 cases and 451 controls were evaluated. Among the cases, approximately 39.3% had nondense breast tissue and 60.7% had dense breast tissue. Among controls, approximately 48.3% had nondense breast tissue and 51.7% had dense breast tissue. After adjustment for potential prognostic risk factors for BC, the odds of developing CBC were found to be significantly higher for patients with dense breasts (odds ratio, 1.80; 95% confidence interval, 1.22-2.64 [P<.01]) than for those with nondense breasts. Patients who received chemotherapy or endocrine therapy were less likely to develop CBC.Conclusions: In women with primary BC, mammographic BD appears to be a risk factor for the development of CBC. Cancer 2017;123:1935-1940. © 2017 American Cancer Society. [ABSTRACT FROM AUTHOR]

We show that every MV-algebra A can be naturally equipped with a filter topology such that A is a topological MV-algebra, which improves the main results on C-topological lattice-ordered groups in both Yang (Sci China Ser A 52(11):2397-2403, 2009) and Gusić (Proc Am Math Soc 126(9):2593-2597, 1998). Furthermore, for a 2-divisible MV-algebra A, we show that the filter topological space is Hausdorff if and only if A is semisimple. [ABSTRACT FROM AUTHOR]

Cerium-gadolinium oxide is a promising material for electrolytes of intermediate temperature solid oxide fuel cells (IT-SOFCs) due to its high electrical conductivity at relatively lower temperatures of 400–700 °C. However, a high sintering temperature of up to 1550 °C is typically required to produce dense CGO electrolyte, eventually leading to an interfacial interdiffusion between the electrolyte and electrode components as well as generate a highly resistive interface which reduces ionic conductivity. Lowering the sintering temperature of the electrolyte will greatly benefit the fabrication of SOFCs. This study examines the effectiveness of introducing nano size CGO particles as an approach to get dense CGO electrolyte at lower sintering temperature. A series of dope suspensions with 0–50% nano size loading were prepared to observe rheology and measure viscosity. Then, 30% loading was selected and casting into flat sheet via phase-inversion technique. The flat sheet was characterized by morphology, surface roughness and mechanical strength tests. The suspension was extruded into dual-layer hollow fiber (DLHF) as well. The electrolyte/anode dual-layer hollow fibers (DLHFs) half-cell of micro-tubular solid oxide fuel cells (MT-SOFCs) were prepared via phase inversion based co-extrusion/co-sintering technique. The developed half-cell was characterized by morphological and gas tightness tests which further compared them with fully micron ones. The results show that the incorporation of 30% nanoparticle yielded to dense and tight CGO layers sintered at temperature 1450 °C, which about 50 °C lower than those reported previously for 100% micron particles. The I–V measurements demonstrated the maximum power density of 0.66 Wcm −2 at temperatures 500 °C using 100% H 2 as fuel. Therefore, this approach is able to reduce the energy cost for the microstructural control of the prepared fiber and thus is recommended for the fabrication of low-cost dual-layer hollow fiber micro tubular SOFCs. [ABSTRACT FROM AUTHOR]

In this paper, we analyze some new properties of nowhere dense and strongly nowhere dense sets. Also, we discuss the images of nowhere dense and strongly nowhere dense sets. Further, we study the properties of weak Baire space in generalized topological spaces. [ABSTRACT FROM AUTHOR]

Background: Left ventricular (LV) torsion is an important indicator of cardiac function that is limited by high inter-test variability (50% of the mean value). We hypothesized that this high inter-test variability is partly due to inconsistent breath-hold positions during serial image acquisitions, which could be significantly improved by using a respiratory navigator for cardiovascular magnetic resonance (CMR) based quantification of LV torsion. Methods: We assessed respiratory-related variability in measured LV torsion with two distinct experimental protocols. First, 17 volunteers were recruited for CMR with cine displacement encoding with stimulated echoes (DENSE) in which a respiratory navigator was used to measure and then enforce variability in end-expiratory position between all LV basal and apical acquisitions. From these data, we quantified the inter-test variability of torsion in the absence and presence of enforced end-expiratory position variability, which established an upper bound for the expected torsion variability. For the second experiment (in 20 new, healthy volunteers), 10 pairs of cine DENSE basal and apical images were each acquired from consecutive breath-holds and consecutive navigator-gated scans (with a single acceptance position). Inter-test variability of torsion was compared between the breath-hold and navigator-gated scans to quantify the variability due to natural breath-hold variation. To demonstrate the importance of these variability reductions, we quantified the reduction in sample size required to detect a clinically meaningful change in LV torsion with the use of a respiratory navigator. Results: The mean torsion was 3.4 ± 0.2°/cm. From the first experiment, enforced variability in end-expiratory position translated to considerable variability in measured torsion (0.56 ± 0.34°/cm), whereas inter-test variability with consistent end-expiratory position was 57% lower (0.24 ± 0.16°/cm, p < 0.001). From the second experiment, natural respiratory variability from consecutive breath-holds translated to a variability in torsion of 0.24 ± 0.10°/cm, which was significantly higher than the variability from navigator-gated scans (0.18 ± 0.06°/cm, p = 0.02). By using a respiratory navigator with DENSE, theoretical sample sizes were reduced from 66 to 16 and 26 to 15 as calculated from the two experiments. Conclusions: A substantial portion (22-57%) of the inter-test variability of LV torsion can be reduced by using a respiratory navigator to ensure a consistent breath-hold position between image acquisitions. [ABSTRACT FROM AUTHOR]

Purpose: To determine the optimal respiratory navigator gating configuration for the quantification of left ventricular strain using spiral cine displacement encoding with stimulated echoes (DENSE) MRI.Materials and Methods: Two-dimensional spiral cine DENSE was performed on a 3 Tesla MRI using two single-navigator configurations (retrospective, prospective) and a combined "dual-navigator" configuration in 10 healthy adults and 20 healthy children. The adults also underwent breathhold DENSE as a reference standard for comparisons. Peak left ventricular strains, signal-to-noise ratio (SNR), and navigator efficiency were compared. Subjects also underwent dual-navigator gating with and without visual feedback to determine the effect on navigator efficiency.Results: There were no differences in circumferential, radial, and longitudinal strains between navigator-gated and breathhold DENSE (P = 0.09-0.95) (as confidence intervals, retrospective: [-1.0%-1.1%], [-7.4%-2.0%], [-1.0%-1.2%]; prospective: [-0.6%-2.7%], [-2.8%-8.3%], [-0.3%-2.9%]; dual: [-1.6%-0.5%], [-8.3%-3.2%], [-0.8%-1.9%], respectively). The dual configuration maintained SNR compared with breathhold acquisitions (16 versus 18, P = 0.06). SNR for the prospective configuration was lower than for the dual navigator in adults (P = 0.004) and children (P < 0.001). Navigator efficiency was higher (P < 0.001) for both retrospective (54%) and prospective (56%) configurations compared with the dual configuration (35%). Visual feedback improved the dual configuration navigator efficiency to 55% (P < 0.001).Conclusion: When quantifying left ventricular strains using spiral cine DENSE MRI, a dual navigator configuration results in the highest SNR in adults and children. In adults, a retrospective configuration has good navigator efficiency without a substantial drop in SNR. Prospective gating should be avoided because it has the lowest SNR. Visual feedback represents an effective option to maintain navigator efficiency while using a dual navigator configuration.Level Of Evidence: 2 J. Magn. Reson. Imaging 2017;45:786-794. [ABSTRACT FROM AUTHOR]

Ti 2 AlN belongs to a family of ternary nano-laminate alloys known as the MAX phases, which exhibit a unique combination of metallic and ceramic properties. In the present work, the dense and high-stability Ti 2 AlN coating has been successfully prepared through the combined cathodic arc/sputter deposition, followed by heat post-treatment. It was found that the as-deposited Ti-Al-N coating behaved a multilayer structure, where (Ti, N)-rich layer and Al-rich layer grew alternately, with a mixed phase constitution of TiN and TiAl x . After annealing at 800 °C under vacuum condition for 1.5 h, although the multilayer structure still was found, part of multilayer interfaces became indistinct and disappeared. In particular, the thickness of the Al-rich layer decreased in contrast to that of as-deposited coating due to the inner diffusion of the Al element. Moreover, the Ti 2 AlN MAX phase emerged as the major phase in the annealed coatings and its formation mechanism was also discussed in this study. The vacuum thermal analysis indicated that the formed Ti 2 AlN MAX phase exhibited a high-stability, which was mainly benefited from the large thickness and the dense structure. This advanced technique based on the combined cathodic arc/sputter method could be extended to deposit other MAX phase coatings with tailored high performance like good thermal stability, high corrosion and oxidation resistance etc. for the next protective coating materials. [ABSTRACT FROM AUTHOR]

Technology of water-stabilized plasma torch was recently substantially updated through introduction of a so-called hybrid concept that combines benefits of water stabilization and gas stabilization principles. The high-enthalpy plasma provided by the WSP-H ('hybrid') torch may be used for thermal spraying of powders as well as liquid feedstocks with high feed rates. In this study, results from three selected experiments with suspension plasma spraying with WSP-H technology are presented. Possibility of deposition of coatings with controlled microstructures was demonstrated for three different ceramics (YSZ-yttria-stabilized zirconia, YAG-yttrium aluminum garnet and AlO) introduced into ethanol-based suspensions. Shadowgraphy was used for optimization of suspension injection and visualization of the liquid fragmentation in the plasma jet. Coatings were deposited onto substrates attached to the rotating carousel with integrated temperature monitoring and air cooling, which provided an excellent reproducibility of the deposition process. Deposition of columnar-like YSZ and dense YAG and AlO coatings was successfully achieved. Deposition efficiency reached more than 50%, as evaluated according to EN ISO 17 836 standard. [ABSTRACT FROM AUTHOR]

Objectives To test the hypothesis that two-dimensional (2D) displacement encoding via stimulated echoes (DENSE) is a reproducible technique for the depiction of segmental myocardial motion in human subjects. Materials and methods Following the approval of the institutional review board (IRB), 17 healthy volunteers without documented history of cardiovascular disease were recruited. For each participant, 2D DENSE were performed twice (at different days) and the images were obtained at basal, midventricular and apical levels of the left ventricle (LV) with a short-axis view. The radial thickening strain (Err), circumferential strain (Ecc), twist and torsion were calculated. The intra-, inter-observer and inter-study variations of DENSE-derived myocardial motion indices were evaluated using coefficient of variation (CoV) and intra-class correlation coefficient (ICC). Results In total, there are 272 pairs of myocardial segments (data points) for comparison. There is good intra- and inter-observer reproducibility for all DENSE-derived measures in 17 participants. There is good inter-study reproducibility for peak Ecc (CoV = 19.64%, ICC = 0.8896, p < 0.001), twist (CoV = 33.11%, ICC = 0.9135, p < 0.001) and torsion (CoV = 13.96%, ICC = 0.8684, p < 0.001). There is moderate inter-study reproducibility for Err (CoV = 38.89%, ICC = 0.7022, p < 0.001). Conclusion DENSE is a reproducible technique for characterizing LV regional systolic myocardial motion on a per-segment basis in healthy volunteers. [ABSTRACT FROM AUTHOR]

By estimating the first-order (direction) and second-order (curvature) derivatives in an image, the parameters of a line or circle passing through a point may be uniquely defined in most cases. This allows to compute a one-to-one Hough transform, every point in the image space voting for one unique point in the parameter space. Moreover, those parameters can be directly estimated on the greyscale image without the need to calculate the contour and without reducing the spatial support of the Hough transform, i.e. densely on the whole image. The general framework using multiscale derivatives is presented, and the one-to-one Hough dense transforms for detecting lines and circles are evaluated and compared with other variants of Hough transforms, from qualitative and computational points of view. [ABSTRACT FROM AUTHOR]

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This paper describes the fabrication of Si-C-Ti ceramics from titanium nanoparticle filled allylhydridopolycarbosilanes (Ti NP-filled AHPCS) using a casting/curing technique followed by pyrolysis at 1000 °C under argon. TGA and XRD have been applied to investigate the mass loss behaviour during ceramization and to gain structural information on the decomposition process of Ti NP-filled AHPCS. TiC is the first phase to nucleate in an amorphous SiC matrix around 800 °C, whereas titanium silicide and MAX phases grow between 800 and 1000 °C. Densities measurements have been done and structural characterization of the final specimens is carried out using XRD and Raman spectroscopy. The process leads to (nano)composites with a density increasing from 2.45 to 2.90 g/cm 3 and a Vickers hardness ranging from 17 to 20.9 GPa according to the AHPCS:Ti ratio fixed in the early stage of the process. The titanium silicide and MAX phases are decomposed during a further heat-treatment between 1000 and 1400 °C to generate TiC/SiC (nano)composites. [ABSTRACT FROM AUTHOR]

Purpose: To describe and assess an automated normalization method for identifying sentinel (septal) regions of myocardial dysfunction in nonischemic, nonvalvular dilated cardiomyopathy (DCM), using an unprecedented combination of the navigator-gated 3D spiral displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging (MRI), radial point interpolation (RPIM) and multiparametric strain z-score (MPZS).Materials and Methods: Navigator-gated 3D spiral DENSE, in a 1.5T MRI machine, was used for acquiring the displacement encoded complex images, MR Analytical Software System (MASS) for automated boundary detection and automated meshfree RPIM for left-ventricular (LV) myocardial strain computation to analyze MPZS in 36 subjects (with n = 17 DCM patients). Pearson's r correlation established relations between global/sentinel MPZS and ejection fraction (EF). The time taken for combined RPIM-MPZS computations was recorded.Results: Maximum MPZS differences were seen between anteroseptal and posterolateral regions in the base (2.0 ± 0.3 vs. 0.9 ± 0.5) and the mid-wall (2.1 ± 0.4 vs. 1.0 ± 0.4). These regional differences were found to be consistent with historically documented septal injury in nonischemic DCM. Correlations were 0.6 between global MPZS and EF, and 0.7 between sentinel MPZS and EF. The time taken for combined RPIM-MPZS computations per subject was 18.9 ± 5.9 seconds.Conclusion: Heterogeneous contractility found in the sentinel regions with the current automated MPZS computation scheme and the correlation found between MPZS and EF may lead to the creation of a new clinical metric in LV DCM surveillance. J. MAGN. RESON. IMAGING 2016;44:993-1002. [ABSTRACT FROM AUTHOR]

Boosting gravimetric and volumetric capacitances simultaneously at a high rate is still a discrepancy in development of graphene based supercapacitors. We report the preparation of dense hierarchical graphene/activated carbon composite aerogels via a reduction induced self-assembly process coupled with a drying post treatment. The compact and porous structures of composite aerogels could be maintained. The drying post treatment has significant effects on increasing the packing density of aerogels. The introduced activated carbons play the key roles of spacers and bridges, mitigating the restacking of adjacent graphene nanosheets and connecting lateral and vertical graphene nanosheets, respectively. The optimized aerogel with a packing density of 0.67 g cm −3 could deliver maximum gravimetric and volumetric capacitances of 128.2 F g −1 and 85.9 F cm −3 , respectively, at a current density of 1 A g −1 in aqueous electrolyte, showing no apparent degradation to the specific capacitance at a current density of 10 A g −1 after 20000 cycles. The corresponding gravimetric and volumetric capacitances of 116.6 F g −1 and 78.1 cm −3 with an acceptable cyclic stability are also achieved in ionic liquid electrolyte. The results show a feasible strategy of designing dense hierarchical graphene based aerogels for supercapacitors. [ABSTRACT FROM AUTHOR]

The effect of temperature, humidity and incident UV light on the photocatalytic activity of two TiO 2 films with different microstructures (dense and mesoporous) was explored in terms of stearic acid degradation. Previous works reported in the literature suggest that the activity of TiO 2 films does not only depend on single factors but also on interactions between them. Hence, the design of experiments (DoE) approach was used in this work to plan the experiments in a systematic way, simultaneously considering several variables. This approach provided an efficient working strategy to explore both individual and interaction effects on the photocatalytic activity of the films. The statistical evidence found here revealed that single factors temperature and mesoporous microstructure have the strongest positive effect on the efficiency of the films. In the case of temperature, this was explained by easier degradation and/or desorption of reaction intermediates. On the other hand, the positive effect of the mesoporous microstructure was correlated with its large surface area. An interaction factor between temperature and incident UV light also affects the activity of the films. Results suggest that this phenomenon depends of the degree of film hydration before the deposition of SA. [ABSTRACT FROM AUTHOR]

Experiments were performed with a particle tracking velocimetry system to investigate the behaviour of inclined negatively buoyant jets with source angles of 15°, 30°, 45°, 60°, 65°, 70°, and 75° in stationary ambient conditions. Velocities were measured in a plane aligned with the central axis of the flow and the experiments were designed such that the flow did not interact with boundaries in the region were the flow behaviour was measured. The results of this study complement previous research, which has largely focused on the mean geometric characteristics and the mean dilution of the discharged fluid. Geometric characteristics, spreading rates, and time-averaged (mean) centreline velocity results are compared with relevant experimental results from previous studies and integral model predictions. Axial and transverse mean velocity profiles at maximum height and the return point provide additional insights into the detrainment of discharged fluid due to the unstable density gradient on the inner side of the flow. [ABSTRACT FROM AUTHOR]

Our aim is to estimate the perspective-effected geometric distortion of a scene from a video feed. In contrast to most related previous work, in this task we are constrained to use low-level spatiotemporally local motion features only. This particular challenge arises in many semiautomatic surveillance systems that alert a human operator to potential abnormalities in the scene. Low-level spatiotemporally local motion features are sparse (and thus require comparatively little storage space) and sufficiently powerful in the context of video abnormality detection to reduce the need for human intervention by more than 100-fold. This paper introduces three significant contributions. First, we describe a dense algorithm for perspective estimation, which uses motion features to estimate the perspective distortion at each image locus and then polls all such local estimates to arrive at the globally best estimate. Second, we also present an alternative coarse algorithm that subdivides the image frame into blocks and uses motion features to derive block-specific motion characteristics and constrain the relationships between these characteristics, with the perspective estimate emerging as a result of a global optimization scheme. Third, we report the results of an evaluation using nine large sets acquired using existing closed-circuit television cameras, not installed specifically for the purposes of this paper. Our findings demonstrate that both proposed methods are successful, their accuracy matching that of human labeling using complete visual data (by the constraints of the setup unavailable to our algorithms). [ABSTRACT FROM PUBLISHER]

This paper deals with dense optical flow estimation from the perspective of the trade-off between quality of the estimated flow and computational cost which is required by real-world applications. We propose a fast and robust local method, denoted by eFOLKI, and describe its implementation on GPU. It leads to very high performance even on large image formats such as 4 K (3,840 × 2,160) resolution. In order to assess the interest of eFOLKI, we first present a comparative study with currently available GPU codes, including local and global methods, on a large set of data with ground truth. eFOLKI appears significantly faster while providing quite accurate and highly robust estimated flows. We then show, on four real-time video processing applications based on optical flow, that eFOLKI reaches the requirements both in terms of estimated flows quality and of processing rate. [ABSTRACT FROM AUTHOR]

Utilizing active function groups and radicals of polymers (polycarbosilane) to react with a mixture of organics (urea) and inorganics(boric acid) during polymer to ceramic conversion process, a novel SiBCN(O) ceramic was successfully prepared via hot-pressing from 380 to 700 °C combined with following pyrolysis at 1400 °C for 2 h in nitrogen atmosphere. The prepared SiBCN(O) ceramic with a low open porosity of ~4%, which maintained amorphous structure still. Experimental results confirmed that the inorganic network of SiBCN(O) amorphous ceramic was constructed by Si–C, Si–N, Si–O, B–N, and B–O bonds. Pyrolysis product BN served as active filler in densification process of the SiBCN(O) ceramic. Additionally, the introduced oxygen from boric acid could be well controlled and thus effectively improved the densification process of the ceramic. [ABSTRACT FROM AUTHOR]

Purpose: To develop a three-dimensional (two dimensions + time) convolutional neural network trained with displacement encoding with stimulated echoes (DENSE) data for displacement and strain analysis of cine MRI., Materials and Methods: In this retrospective multicenter study, a deep learning model (StrainNet) was developed to predict intramyocardial displacement from contour motion. Patients with various heart diseases and healthy controls underwent cardiac MRI examinations with DENSE between August 2008 and January 2022. Network training inputs were a time series of myocardial contours from DENSE magnitude images, and ground truth data were DENSE displacement measurements. Model performance was evaluated using pixelwise end-point error (EPE). For testing, StrainNet was applied to contour motion from cine MRI. Global and segmental circumferential strain (E cc ) derived from commercial feature tracking (FT), StrainNet, and DENSE (reference) were compared using intraclass correlation coefficients (ICCs), Pearson correlations, Bland-Altman analyses, paired t tests, and linear mixed-effects models., Results: The study included 161 patients (110 men; mean age, 61 years ± 14 [SD]), 99 healthy adults (44 men; mean age, 35 years ± 15), and 45 healthy children and adolescents (21 males; mean age, 12 years ± 3). StrainNet showed good agreement with DENSE for intramyocardial displacement, with an average EPE of 0.75 mm ± 0.35. The ICCs between StrainNet and DENSE and FT and DENSE were 0.87 and 0.72, respectively, for global E cc and 0.75 and 0.48, respectively, for segmental E cc . Bland-Altman analysis showed that StrainNet had better agreement than FT with DENSE for global and segmental E cc ., Conclusion: StrainNet outperformed FT for global and segmental E cc analysis of cine MRI. Keywords: Image Postprocessing, MR Imaging, Cardiac, Heart, Pediatrics, Technical Aspects, Technology Assessment, Strain, Deep Learning, DENSE Supplemental material is available for this article. © RSNA, 2023., Competing Interests: Disclosures of conflicts of interest: Y.W. Supported by the American Heart Association (2020AHAPRE0000203801); U.S. provisional patent applications serial numbers 63/149,900 ("System and Method for Improved Cardiac MRI Feature Tracking by Learning from Displacement-Encoded Imaging") and 63/408,760 ("Method and System for Strain Analysis that Includes CMR-trained StrainNet to Echocardiography"). C.S. U.S. provisional patent applications serial numbers 63/149,900 ("System and Method for Improved Cardiac MRI Feature Tracking by Learning from Displacement-Encoded Imaging") and 63/408,760 ("Method and System for Strain Analysis that Includes CMR-trained StrainNet to Echocardiography"). S.G. No relevant relationships. D.C.A. No relevant relationships. P.C. No relevant relationships. M.V. No relevant relationships. K.M. Co-applicant (2022) for National Health Service (NHS) Greater Glasgow and Clyde Endowment Funding (GN21CA412) for "Scar Characterisation with Cardiac MR to Predict Ventricular Arrhythmias" (£25 000); principal applicant (2021) for NHS Greater Glasgow and Clyde Endowment Funding (GN20CA408) for "Centre-specific Stress Perfusion Reference Ranges for the 3-T MRI Scanner" (£14 910); co-applicant (2021) for NHS Greater Glasgow and Clyde Endowment Funding (GN20ID164) for "CISCO-19 Visit 3" (£96 370); co-applicant (2021) for Chief Scientist Office–Long Term Effects of COVID (COV/LTE/20/10) for "Prevention and Early Treatment of COVID-19 Long Term Effects: A Randomised Clinical Trial of Resistance Exercise" (£288 660); principal applicant (2020) for Tenovus Scotland (S20-08) for "Investigating the Long-term Cardiac Sequelae of Trastuzumab Therapy" (£19 600); principal applicant (2022) for SoftMech Feasibility Funds for "Using Advanced CMR Techniques and Computational Modeling in Female Volunteers to Detect Pump Function Changes in Cancer Patients" (£10 000); principal applicant (2020) for Wellcome ISSF COVID Response Fund for "A Vascular Biology Nested Study within CISCO-19" (£10 000); co-applicant (2020) for Chief Scientist Office, Rapid Research COVID-19 for "Cardiovascular Imaging in SARS-CoV-2 (CISCO-19)" (COV/GLA/20/05) (£48, 618; MRI and CTCA scan costs in-kind); co-applicant (2020) for EPSRC Impact Acceleration Account (IAA) Cardiac Endotypes in COVID-19 for "Quantification and Mechanisms of Cardiac Injury" (£48 304) C.B. Employed by the University of Glasgow, which holds consultancy and research agreements for his work with Abbott Vascular, AstraZeneca, Auxilius Pharma, Boehringer Ingelheim, Causeway Therapeutics, Coroventis, Genenetech, GSK, HeartFlow, Menarini, Neovasc, Novartis, Siemens Healthcare, and Valo Health, with grants, contracts, consulting fees, and payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or education events paid to the institution, University of Glasgow; named on a pending patent for the use of zibotentan for microvascular angina, patent held by the University of Glasgow; participation on PROTECT-TAVR UK DSMB (unpaid); president of the British Society of Cardiovascular Magnetic Resonance (unpaid); past member of the Clinical Trials Committee of the Society for Cardiovascular Magnetic Resonance (SCMR) (unpaid); in-kind support for clinical research studies involving Abbott Vascular, AstraZeneca, Boehringer Ingelheim, Coroventis, GSK, HeartFlow, Novartis, and Siemens Healthcare, by contract with the University of Glasgow. C.M.H. Supported by the National Institutes of Health (NIH). L.J. No relevant relationships. B.K.F. Grant funding from the NIH (NIH DP5 OD-012132, NIH P20 GM-103527, NIH UL1 TR-000117) made to the institution where some of the cardiac MRI data was collected; full-time employment with Tempus Labs that began in late 2021 after the work was completed. J.J.C. No relevant relationships. J.C. No relevant relationships. A.D.S. The CMR Unit, Royal Brompton Hospital, receives research support from Siemens. P.F.F. Contribution to this work was funded by the British Heart Foundation (BHF), grant number RG/19/1/34160. J.N.O. No relevant relationships. D.B.E. NIH grant numbers NIH National Heart, Lung, and Blood Institute (NHLBI) R01 131975 and 131823; joint 6/8ths Stanford University/Veterans Affairs (SU/VA) appointment specified by a formal Memorandum of Understanding between SU and the VA, there is no possibility of dual compensation for the same work, no conflict of interest regarding such work, and the overall set of responsibilities meets the test of reasonableness; support for the following listed projects and proposals includes support managed through SU and through the investigator’s VA appointment, Palo Alto Veterans Institute for Research (PAVIR) and the VA Palo Alto Health Care System, primary place of performance for all is SU: "High Resolution Whole-Breast MRI at 3.0T Major," research to develop much higher resolution breast MRI, allowing better classification of small lesions to prevent unnecessary biopsy and detect cancer earlier, active support, project number R01 EB009055, source of support is IH/NIBIB, primary place of performance is SU, March 2020–November 2023, total award amount (including indirect costs) is $2 559 180; "Using Atrial Mechanics to Identify Fibrosis in Patients with Atrial Fibrillation," to use MRI of atrial mechanics to identify localized fibrosis and hypothesize that attenuated mechanics provide a robust measure of atrial fibrosis, active support, project number, source of support is NIH/NHLBI, June 2020–May 2024, total award amount (including indirect costs) is $2 787 583; "Biomechanical Optimization of Cardiac Valve Repair Operations," to validate our findings using large animal cardiac surgery models, and then hopefully translate these discoveries directly to the operating room in the human clinical arena, active support, project number R01 HL152155, source of support is NIH/NHLBI, primary place of performance is SU, May 2020–April 2024, total award amount (including indirect costs) is $2 762 997; "Advanced MR Applications Development–Tiger Team Years 13 & 14," comprises five projects in neuroimaging, high-field, pediatric, body, and musculoskeletal MRI, to advance clinical imaging capabilities, with the goals to develop and evaluate MR pulse sequences and hardware, active support, project number A117, source of support is GE Healthcare, June 2020–October 2022, total award amount (including indirect costs) is $1 936 583; "GE Healthcare–Stanford Artificial Intelligence in Medical Imaging Research," to develop methods of upstream medical imaging artificial intelligence to optimize the selection, scheduling, protocoling, and execution of exams, active support, project number A113, A114, A118, A120, source of support is GE Healthcare, July 2020–June 2024, total award amount (including indirect costs) is $3 342 138; "Abbreviated Non-Contrast-Enhanced MRI for Breast Cancer Screening," to provide accurate, low-cost, comfortable, MRI screening without intravenous contrast media, in a 10-minute exam, which will ultimately enable more effective and comfortable breast cancer screening for millions of women for whom x-ray mammography is insufficient, active support, project number R01 CA249893, source of support is NIH/NCI, primary place of performance is SU, February 2021–January 2026, total award amount (including indirect costs) is $3 127 573; "Enabling the Next Generation of High Performance Pediatric Whole-Body MR Imaging," to create and validate the next generation systems for pediatric MRI, active support, project number U01 EB029427, source of support is NIH/NIBIB, August 2020–July 2025, total award amount (including indirect costs) is $4 189 084; "Improved Diagnostic MRI Around Metallic Implants," active support, project number SPO#192723, source of support is the University of Southern California/NIH, February 2022–November 2026, total award amount (including indirect costs) is $967 045; "MR/PET Motion Correction from Coil Fingerprints," active support, project number, R01 EB029306, source of support is the NIH, September 2022–January 2024, total award amount (including indirect costs) is $1 261 824; "Developing ultra high field connectome hardware for order-of-magnitude increase in MRI sensitivity," pending support, project number SPO#280964, source of support is the NIH, primary place of performance is SU, July 1, 2023–June 30, 2028, total award amount (including indirect costs) is $4 403 210; "Fast and Accurate Cardiovascular 4D-Flow MRI for Pediatrics," pending support, project number SPO#232860, source of support is the NIH, April 1, 2023–March 31, 2028, total award amount (including indirect costs) is $3 861 471; projects managed and/or administered by PAVIR and VAPAHCS: "Using Atrial Mechanics to Identify Fibrosis in Patients with Atrial Fibrillation," to use MRI of atrial mechanics to identify localized fibrosis and hypothesize that attenuated mechanics provide a robust measure of atrial fibrosis, active support, project number R01 HL152256, source of support is NIH/NHLBI, June 2020–May 2024, total award amount (including indirect costs) is $271,187; "Implementing the Enhanced Liver Fibrosis (ELF) test to optimize prognostic screening and monitoring of hepatic fibrosis among patients at risk for non-alcoholic fatty liver disease (NAFLD)," to improve clinical care by using ELF to identify high-risk patients with hepatic fibrosis compared to standard-of-care and monitor patients for rapid disease progression or response to treatment, active support, project number C00239205, source of support is Siemens Medical Solutions USA, primary place of performance is VAPAHCS, September 2021–October 2024, total award amount (including indirect costs) is $718 147; "Abbreviated US and MRI versus FibroScan for diffuse liver disease," to improve clinical care by comparing the accuracy of vibration-controlled transient elastography (VCTE), US, and MRI for assessment of NAFLD/NASH and to introduce new US and MRI techniques to improve detection of NAFLD/NASH, active support, source of support is Siemens Medical Solutions USA, primary place of performance is VAPAHCS, September 2021–October 2024, total award amount (including indirect costs) is $551 656; author’s graduate students receive in-kind contributions. K.C.B. NHLBI grant, AHA grant, Medtronic grant, Siemens; consulting fees from Medtronic; payment or honoraria for speaker, ACC; US patent planned, issued, or pending; participation on a Data Safety Monitoring Board or Advisory Board for Left v. Left RCT funded by PCORI, 2022-present; vice-chair, HRS, research committee chair, SCMR, Clinical Trials Committee (starting in early February 2023, previously a member of the committee for several years), grant reviewer, NIH; research funding gift from Seraph Foundation. F.H.E. Research support from Siemens Healthineers Ivy Biomedical Innovation Fund; patents planned, issued, or pending, PCT/US2022/014903 Intramyocardial Tissue Displacement and Motion Measurement and Strain Analysis from MRI Cine Images Using DENSE Deep Learning; patent application number 63/408,760 entitled "Method and System for Strain Analysis that Includes CMR-trained StrainNet to Echocardiography.”, (© 2023 by the Radiological Society of North America, Inc.)

Letbe a nonempty subset of the set of submodules of a moduleM. ThenMis called a-extending module if for eachXinthere exists a direct summandDofMsuch thatXis essential inD. In general, it is known that an essential extension of a-extending module is not-extending. In this paper, our goal is to show how to construct essential extensions of a module which areextending by using a set of representatives of a certain equivalence relation on the set of all idempotent endomorphisms of the injective hull of the module. Also we characterize when the rational hull of a module is-extending in terms of such a set of representatives. Moreover we show that several well known types of-extending conditions (e.g., extending and FI-extending) transfer from module to its rational hull. [ABSTRACT FROM PUBLISHER]

Time series remote sensing products with both fine spatial and dense temporal resolutions are urgently needed for many earth system studies. The development of small satellite constellations with identical sensors affords novel opportunities to provide such kind of earth observations. In this paper, a new dense time series 30-m image product was proposed respectively based on an 8-day, 16-day and monthly composition. The products were composited by the Charge Coupled Device (CCD) images from the 2-day revisit small satellite constellation for environmental monitoring and disaster mitigation of China (HJ-1A/B). Taking the Zoige plateau in China as a case area where it is covered by highly heterogeneous vegetation landscapes, a detailed methodology was introduced on how to use 183 scenes of CCD images in 2010 to create composite products. The quality of the HJ CCD composites was evaluated by inter-comparison with the monthly 30-m global Web-Enabled Landsat Data (WELD), 16-day 500-m MODIS NDVI, and 8-day 500-m MODIS surface reflectance products. Results showed that the radiometric consistency between HJ and WELD composited Top Of Atmosphere (TOA) reflectance was in good agreement except for May, June, July and August when more clouds and invalid data gaps appeared in WELD. Visual assessment and temporal profile analysis also revealed that HJ possessed better visual effects and temporal coherence than that of WELD. The comparison between HJ and MODIS products indicated that HJ composites were radiometrically consistent with MODIS products over areas consisting of large patches of homogeneous surface types, but can better reflect the detailed spatial differences in regions with heterogeneous landscapes. This paper highlights the potential of compositing HJ-1A/B CCD images, allowing for providing a cloud free, time-space consistent, 30-m spatial resolution, and dense in time series image product. Meanwhile, the proposed products could also be treated as a reference to generate regional or even global composited products for the on-going satellite constellations and even for the forthcoming satellite missions such as Sentinel-2A/B. [ABSTRACT FROM AUTHOR]

Aerial thermal imagery has been recently applied to quantitative analysis of several scenes. For the mapping purpose based on aerial thermal imagery, high accuracy photogrammetric process is necessary. However, due to low geometric resolution and low contrast of thermal imaging sensors, there are some challenges in precise 3D measurement of objects. In this paper the potential of thermal video in 3D surface generation is evaluated. In the pre-processing step, thermal camera is geometrically calibrated using a calibration grid based on emissivity differences between the background and the targets. Then, Digital Surface Model (DSM) generation from thermal video imagery is performed in four steps. Initially, frames are extracted from video, then tie points are generated by Scale-Invariant Feature Transform (SIFT) algorithm. Bundle adjustment is then applied and the camera position and orientation parameters are determined. Finally, multi-resolution dense image matching algorithm is used to create 3D point cloud of the scene. Potential of the proposed method is evaluated based on thermal imaging cover an industrial area. The thermal camera has 640×480 Uncooled Focal Plane Array (UFPA) sensor, equipped with a 25 mm lens which mounted in the Unmanned Aerial Vehicle (UAV). The obtained results show the comparable accuracy of 3D model generated based on thermal images with respect to DSM generated from visible images, however thermal based DSM is somehow smoother with lower level of texture. Comparing the generated DSM with the 9 measured GCPs in the area shows the Root Mean Square Error (RMSE) value is smaller than 5 decimetres in both X and Y directions and 1.6 meters for the Z direction. [ABSTRACT FROM AUTHOR]

Background: Displacement Encoding with Stimulated Echoes (DENSE) encodes displacement into the phase of the magnetic resonance signal. The encoding frequency (ke) maps the measured phase to tissue displacement while the strength of the encoding gradients affects image quality. 2D cine DENSE studies have used a ke of 0.10 cycles/mm, which is high enough to remove an artifact-generating echo from k-space, provide high sensitivity to tissue displacements, and dephase the blood pool. However, through-plane dephasing can remove the unwanted echo and dephase the blood pool without relying on high ke. Additionally, the high sensitivity comes with the costs of increased phase wrapping and intra-voxel dephasing. We hypothesized that ke below 0.10 cycles/mm can be used to improve image characteristics and provide accurate measures of cardiac mechanics. Methods: Spiral cine DENSE images were obtained for 10 healthy subjects and 10 patients with a history of heart disease on a 3 T Siemens Trio. A mid-ventricular short-axis image was acquired with different ke: 0.02, 0.04, 0.06, 0.08, and 0.10 cycles/mm. Peak twist, circumferential strain, and radial strain were compared between acquisitions employing different ke using Bland-Altman analyses and coefficients of variation. The percentage of wrapped pixels in the phase images at end-systole was calculated for each ke. The dephasing of the blood signal and signal to noise ratio (SNR) were also calculated and compared. Results: Negligible differences were seen in strains and twist for all ke between 0.04 and 0.10 cycles/mm. These differences were of the same magnitude as inter-test differences. Specifically, the acquisitions with 0.04 cycles/mm accurately quantified cardiac mechanics and had zero phase wrapping. Compared to 0.10 cycles/mm, the acquisitions with 0.04 cycles/mm had 9 % greater SNR and negligible differences in blood pool dephasing. Conclusions: For 2D cine DENSE with through-plane dephasing, the encoding frequency can be lowered to 0.04 cycles/mm without compromising the quantification of twist or strain. The amount of wrapping can be reduced with this lower value to greatly simplify the input to unwrapping algorithms. The strain and twist results from studies using different encoding frequencies can be directly compared. [ABSTRACT FROM AUTHOR]

Membrane gas solvent contactors show potential for carbon capture, because it incorporates the advantage of both solvent and membrane technology. Here, three thin film composite membrane contactors are trialed for the absorption of CO 2 into monoethanolamine (MEA) solvent. These are prepared from coating dense poly (1-trimethylsilyl-1-propyne) (PTMSP), a Polymer of Intrinsic Microporosity (PIM-1) and Teflon AF1600 on a porous PP support. It was found that after 1 h of operation, the PTMSP and PIM-1 membrane contactors provided the highest overall mass transfer coefficient, while Teflon AF1600 performance was lower. Comparison of the CO 2 permeability through the membrane based on mass transfer resistance calculations showed that both PTMSP and PIM-1 had significantly hindered CO 2 permeance compared to that expected from gas permeability measurements. This was due to the presence of water and MEA sorbed within the non-porous layer hindering the migration of CO 2 through both membranes. Importantly, for both PTMSP and PIM-1 membranes water migrated over time from the dense layer into the porous support and wetted the pores. The Teflon AF1600 dense layer was resistant to water and MEA sorption and hence the permeation of CO 2 through this layer was comparable to that expected from gas permeability measurements. Equally important, after 10 h of operation no change in overall mass transfer coefficient was observed indicating that Teflon AF1600 was able to prevent water from wetting the porous PP support. Hence, for thin film composite membrane contactors to be effective for CO 2 separation, the dense layer must have a high CO 2 permeability as well as be resistant to water sorption. [ABSTRACT FROM AUTHOR]

The article extends the notion of rigidity from algebraic frames to the theory of general frames that are not necessarily algebraic. In particular, the aim of the article is to investigate the relationship between rigid, skeletal, and dense frame homomorphisms, and study the Booleanization of frames in terms of rigidity. Some new concepts on domain preserving, domain reflecting, and strongly skeletal maps are introduced. [ABSTRACT FROM AUTHOR]

In this paper, we give an explicit criterion to decide the density of finitely generated additive subgroups of ℝn and ℂn. [ABSTRACT FROM AUTHOR]

Increasing numbers of Geostationary Earth Orbit satellites have led to the requirement of accurate station keeping and precise orbit prediction to avoid collision between satellites. In the case of ground-based optical observation, angular resolution is better than other tracking systems, such as radar systems; however, the observation time of optical observation is limited by weather or lighting conditions. To develop an effective optical observation strategy, the optical observation campaign from January to February 2014 for Communication, Ocean and Meteorological Satellite (COMS) was conducted. Because COMS is a controlled satellite with station keeping manoeuvres performed twice a week, the observation results for 1- and 2-day observations were analysed. Sparse and sporadic cases for the sequential observation of multiple satellites and a dense case for the intensive observation of specific targets were assumed for the experiments. In the 1-day arc observation experiment, the estimated orbits for dense observation cases over 10% of the orbital period showed that the maximum difference was less than 40 km (station keeping area) for 7-day propagation compared to the estimation result using the whole 1-day measurement. For the 2-day arc observation, the orbit estimation difference could be maintained within 2 km using a more frequent observation than the 1-h interval for 13 h that was used in the sparse case. Additionally, the longitudinal and latitudinal positions via the estimation result using the optical observation were compared with the Two-Line Elements (TLEs) and operator’s data. Through this study, an adequate optical tracking strategy was studied, and the possibility of cooperation with other systems was also validated. [ABSTRACT FROM AUTHOR]

In order to reveal the unsteady features of gas–solid flow, the pressure fluctuations were measured at different locations along the length of the pipeline while conveying powders through the pipeline. Power spectral density (PSD) functions were obtained for the analysis of the pressure fluctuation. Two types of powders (fly ash and alumina) were used in this analysis. The PSD analysis was conducted by taking into account different aspects such as flow conditions (dilute or dense), location of transmitter (top and bottom transmitters), location of transmitter along the length of the pipeline (three different locations), material property (fly ash or alumina), etc. Analysis of signals from top and bottom transmitters shows that it is not possible to identify the flow mode at upper and lower portions of pipeline. The magnitude of power is found to be higher for alumina as compared to fly ash. PSD parametric analysis reveals that frequency bandwidth and average power decreases exponentially with increase in solid loading ratio. [ABSTRACT FROM AUTHOR]