Dual Images Research Articles

Modeling the shape and composition of the human body using dual energy X-ray absorptiometry images.

There is growing evidence that body shape and regional body composition are strong indicators of metabolic health. The purpose of this study was to develop statistical models that accurately describe holistic body shape, thickness, and leanness. We hypothesized that there are unique body shape features that are predictive of mortality beyond standard clinical measures. We developed algorithms to process whole-body dual-energy X-ray absorptiometry (DXA) scans into body thickness and leanness images. We performed statistical appearance modeling (SAM) and principal component analysis (PCA) to efficiently encode the variance of body shape, leanness, and thickness across sample of 400 older Americans from the Health ABC study. The sample included 200 cases and 200 controls based on 6-year mortality status, matched on sex, race and BMI. The final model contained 52 points outlining the torso, upper arms, thighs, and bony landmarks. Correlation analyses were performed on the PCA parameters to identify body shape features that vary across groups and with metabolic risk. Stepwise logistic regression was performed to identify sex and race, and predict mortality risk as a function of body shape parameters. These parameters are novel body composition features that uniquely identify body phenotypes of different groups and predict mortality risk. Three parameters from a SAM of body leanness and thickness accurately identified sex (training AUC = 0.99) and six accurately identified race (training AUC = 0.91) in the sample dataset. Three parameters from a SAM of only body thickness predicted mortality (training AUC = 0.66, validation AUC = 0.62). Further study is warranted to identify specific shape/composition features that predict other health outcomes.

Object-Based Building Damage Assessment Methodology Using Only Post Event ALOS-2/PALSAR-2 Dual Polarimetric SAR Intensity Images

Earthquake-induced building damage assessment is an indispensable prerequisite for disaster impact assessment, and the increasing availability of high-resolution Synthetic Aperture Radar (SAR) imagery has made it possible to construct damaged building inventories soon after earthquakes strike. However, the shortage of pre-seismic SAR datasets and the lack of available building footprint data pose challenges for rapid building damage assessment. Taking advantage of recent advances in machine learning algorithms, this study proposes an object-based building damage assessment methodology that uses only post-event SAR imagery. A Random Forest machine learning-based object classification, a simplified approach to the extraction of built-up areas, was developed and tested on two ALOS2/PALSAR-2 dual polarimetric SAR images acquired in affected areas soon after the 2015 Nepal earthquake. In addition, a series of texture metrics as well as the random scattering metric and reflection symmetry metric were found to significantly enhance classification accuracy. The feature selection was found to have a positive effect on overall performance. Moreover, the proposed Random Forest framework resulted in overall accuracies of 93% with a kappa coefficient of 0.885 when the object scale of 60 × 60 pixels and 15 features were adopted. A comparative experiment with the k-nearest neighbor framework demonstrated that the Random Forest framework is a significant step toward the achievement of a balanced, two-class classification.

Fetal cardiac function: Feasibility in obtaining the right modified myocardial performance index in a single Doppler waveform.

We aimed to assess the feasibility of assessing the fetal right Myocardial Performance Index (RMPI) using single waveform and to compare absolute values with dual technique. We studied 145 morphologically normal appropriately grown fetuses at 16-28 weeks' gestation with local Ethics Committee approval using fixed machine settings: Doppler sweep velocity at 15 cm/s; angle of insonation <150; wall motion filter 300 Hz. Doppler gate was 3 mm, increased to 4-5 mm if needed. RMPI was obtained twice in the same fetus; using 'dual-image' and 'single-image' techniques. Dual images were acquired as previously described. Single images were taken from the tip or just below the tricuspid valve towards the ventricular septum in the apical four-chamber view. RMPI was calculated using two-value (a-b/b) or three-value (ICT+IRT/ET) formulae where 'a', 'b' or (ET) represent the isovolumetric and ejection times, and ICT and IRT represent the isovolumetric contraction and relaxation times. Dual image was accessible in 100% of fetuses. Single-image acquisition was 100%, 92.3% and 76.5% at 16+0-24+0, 24+1-27+0, and 27+1-28+0 weeks respectively (95.2% overall). Doppler gate increased in 23 cases (16.6%); 8/17 (47%) at 27+1-28+0 weeks' gestation. Mean and standard deviation for 'dual image' and 'single image' were: RMPI 0.46 ± 0.09 and 0.49 ± 0.07; 'a' 249.06 ± 11.50 and 249.11 ± 11.93; 'b' 170.85 ± 8.95 and 167.62 ± 8.39. Single-image acquisition RMPI is highly feasible from 16 to 26 weeks gestation. Difference in mean values may represent overestimation of ejection time in the 'dual-image' technique.

Visual and infrared graphic applied through dedicated halftoning for transparent polypropylene packaging

In the security managing of packaging infrared transparent graphics on polypropylene material is involved. Preparing of dual images of objects, textual messages in visual-V and NIR-Z domain is extended with dual separation which defines new flexographic procedures of colour mixing. Profiles describing and defining V and Z twin pairs are strictly associated with printing conditions. Quality of twin pairs is achieved with spectroscopic analysis of measuring light absorption in visual and near infrared spectrum. Halftoning algorithms support transparent flexographic foil that does not absorb printing inks and does not penetrate into the printing media. Line halftoning element with ''knee'' effect is developed to additionally demonstrate the plasticity of primary objects or letters. The balance between equalizing of inks in the visual domain, and their differentiation in NIR- Z spectral domain is achieved. Relatively coarse shape and structure of screening elements, low ruling, is suitable for additional transparency of graphics, so that the underlying goods packed in foil can be observed. Secondary, hidden graphics is accessible through NIR camera technology. In that way multiple security options are ensured.

Three-dimensional measurement of bubble volume based on dual perspective imaging

This paper presents a new three-dimensional (3D) volume measurement approach of bubble in gas-liquid two-phase flow. According to the dual perspective imaging principle, bubble feature images can be captured from two different view angles. The least square ellipse fitting algorithm is used to figure out the feature parameters from the captured images. Then the 3D volume of bubble can be quantitatively measured. Compaerd with the traditional volume estimation methods based on single perspective imaging, it can effectively reduce the loss of bubble feature information. In the experiment, the 3D volume reconstruction of bubbles from dual perspective images is conducted, and the variation of bubble volume in the bubble rising process is studied. The results show that the measurement accuracy based on the proposed 3D method is higher than those based on traditional methods. The volume of rising bubble is periodically changed, which indicates that bubble achieves periodic rotation and deformation in the rising process.

Application of a dual energy X-ray imaging method on breast specimen

The purpose of this study was to evaluate a dual energy method, developed by our group, on a breast cancer specimen. A modified radiographic X-ray tube combined with a high resolution complementary metal-oxide semiconductor (CMOS) active pixel sensor (APS) X-ray detector was used. A 40/70kV spectral combination was filtered with 100μm cadmium (Cd) and 1000μm copper (Cu) for the low/high-energy combination. Dual energy images were obtained from a formalin-fixed breast cancer specimen for various entrance surface doses (ESD). Initial results showed that the DE images were directly comparable with the mammographic image and similar or even increased calcification information was identified, with mean glandular dose values at acceptable levels.

Pathologic stratification of operable lung adenocarcinoma using radiomics features extracted from dual energy CT images.

PurposeTo evaluate the usefulness of surrogate biomarkers as predictors of histopathologic tumor grade and aggressiveness using radiomics data from dual-energy computed tomography (DECT), with the ultimate goal of accomplishing stratification of early-stage lung adenocarcinoma for optimal treatment.ResultsPathologic grade was divided into grades 1, 2, and 3. Multinomial logistic regression analysis revealed i-uniformity and 97.5th percentile CT attenuation value as independent significant factors to stratify grade 2 or 3 from grade 1. The AUC value calculated from leave-one-out cross-validation procedure for discriminating grades 1, 2, and 3 was 0.9307 (95% CI: 0.8514–1), 0.8610 (95% CI: 0.7547–0.9672), and 0.8394 (95% CI: 0.7045–0.9743), respectively.Materials and MethodsA total of 80 patients with 91 clinically and radiologically suspected stage I or II lung adenocarcinoma were prospectively enrolled. All patients underwent DECT and F-18-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT, followed by surgery. Quantitative CT and PET imaging characteristics were evaluated using a radiomics approach. Significant features for a tumor aggressiveness prediction model were extracted and used to calculate diagnostic performance for predicting all pathologic grades.ConclusionsQuantitative radiomics values from DECT imaging metrics can help predict pathologic aggressiveness of lung adenocarcinoma.

Mapping Annual Forest Cover in Sub-Humid and Semi-Arid Regions through Analysis of Landsat and PALSAR Imagery

Accurately mapping the spatial distribution of forests in sub-humid to semi-arid regions over time is important for forest management but a challenging task. Relatively large uncertainties still exist in the spatial distribution of forests and forest changes in the sub-humid and semi-arid regions. Numerous publications have used either optical or synthetic aperture radar (SAR) remote sensing imagery, but the resultant forest cover maps often have large errors. In this study, we propose a pixel- and rule-based algorithm to identify and map annual forests from 2007 to 2010 in Oklahoma, USA, a transitional region with various climates and landscapes, using the integration of the L-band Advanced Land Observation Satellite (ALOS) PALSAR Fine Beam Dual Polarization (FBD) mosaic dataset and Landsat images. The overall accuracy and Kappa coefficient of the PALSAR/Landsat forest map were about 88.2% and 0.75 in 2010, with the user and producer accuracy about 93.4% and 75.7%, based on the 3270 random ground plots collected in 2012 and 2013. Compared with the forest products from Japan Aerospace Exploration Agency (JAXA), National Land Cover Database (NLCD), Oklahoma Ecological Systems Map (OKESM) and Oklahoma Forest Resource Assessment (OKFRA), the PALSAR/Landsat forest map showed great improvement. The area of the PALSAR/Landsat forest was about 40,149 km2 in 2010, which was close to the area from OKFRA (40,468 km2), but much larger than those from JAXA (32,403 km2) and NLCD (37,628 km2). We analyzed annual forest cover dynamics, and the results show extensive forest cover loss (2761 km2, 6.9% of the total forest area in 2010) and gain (3630 km2, 9.0%) in southeast and central Oklahoma, and the total area of forests increased by 684 km2 from 2007 to 2010. This study clearly demonstrates the potential of data fusion between PALSAR and Landsat images for mapping annual forest cover dynamics in sub-humid to semi-arid regions, and the resultant forest maps would be helpful to forest management.

Trabecular Bone Score and Incident Fragility Fracture Risk in Adults with Reduced Kidney Function.

Trabecular bone score is a gray-level textural measure obtained from dual energy x-ray absorptiometry lumbar spine images that provides information independent of areal bone mineral density. The association between trabecular bone score and incident fractures in adults with reduced kidney function and whether this association differs from that of adults with normal kidney function are unknown. We included 1426 participants ages ≥40 years old (mean age of 67 years) in the community-based Canadian Multicentre Osteoporosis Study. We stratified participants at cohort entry (2005-2008) by eGFR (eGFR<60 ml/min per 1.73 m2 [n=199; 72.4% stage 3a, 25.1% stage 3b, and 2.5% stage 4] versus ≥60 ml/min per 1.73 m2 [n=1227]). Trabecular bone score was obtained from lumbar spine (L1-L4) dual energy x-ray absorptiometry images, with a lower trabecular bone score representing worse bone structure. Over an average of 4.7 years follow-up (maximum follow-up of 5 years), we documented incident fragility (low-trauma) fracture events (excluding craniofacial, foot, and hand sites). We used a modified Kaplan-Meier estimator to determine the 5-year probability of fracture. Cox proportional hazard regression per SD lower trabecular bone score expressed the gradient of fracture risk. Individuals with an eGFR<60 ml/min per 1.73 m2 who had a trabecular bone score value below the median (<1.277) had a significantly higher 5-year fracture probability than those above the median (18.1% versus 6.2%; P=0.01). The association between trabecular bone score and fracture was independent of bone mineral density and other clinical risk factors in adults with reduced and normal kidney function (adjusted hazard ratio per SD lower trabecular bone score: eGFR<60 ml/min per 1.73 m2: adjusted hazard ratio, 1.62; 95% confidence interval, 1.04 to 2.51; eGFR≥60 ml/min per 1.73 m2: adjusted hazard ratio, 1.44; 95% confidence interval, 1.13 to 1.83). Lower lumbar spine trabecular bone score is independently associated with a higher fracture risk in adults with reduced kidney function. Additional study is needed to examine the association between trabecular bone score and fractures in individuals with diagnosed CKD-mineral and bone disorder.

Substantial CT radiation dose reduction does not affect the preference for CT over direct digital radiography to diagnose isolated zygomatic fractures – A study in human cadavers

IntroductionZygomatic fractures can be diagnosed with either computed tomography (CT) or direct digital radiography (DR). The aim of the present study was to assess the effect of CT dose reduction on the preference for facial CT versus DR for accurate diagnosis of isolated zygomatic fractures. Materials and methodsEight zygomatic fractures were inflicted on four human cadavers with a free fall impactor technique. The cadavers were scanned using eight CT protocols, which were identical except for a systematic decrease in radiation dose per protocol, and one DR protocol. Single axial CT images were displayed alongside a DR image of the same fracture creating a total of 64 dual images for comparison. A total of 54 observers, including radiologists, radiographers and oral and maxillofacial surgeons, made a forced choice for either CT or DR. ResultsForty out of 54 observers (74%) preferred CT over DR (all with P < 0.05). Preference for CT was maintained even when radiation dose reduced from 147.4 μSv to 46.4 μSv (DR dose was 6.9 μSv). Only a single out of all raters preferred DR (P = 0.0003). The remaining 13 observers had no significant preference. ConclusionThis study demonstrates that preference for axial CT over DR is not affected by substantial (∼70%) CT dose reduction for the assessment of zygomatico-orbital fractures.

Color texture classification of yarn-dyed woven fabric based on dual-side scanning and co-occurrence matrix

Color texture classification as a part of fabric analysis is significant for textile manufacturing. In this research, a new artificial intelligence method based on a dual-side co-occurrence matrix and a back propagation neural network has been proposed for color texture classification, which could achieve relatively accurate classification results for yarn-dyed woven fabric compared with the traditional co-occurrence matrix for a single-side image. Firstly, a laboratory dual-side imaging system has been established to digitize the upper-side and lower-side images sequentially. Secondly, the dual-side co-occurrence matrix could be generated based on these dual images; four texture features could be extracted for the evaluation of the fabric texture characteristics. Thirdly, a well-trained back propagation neural network was established with the four defined features as the input vectors and the color texture type of yarn-dyed woven fabric as the output vector. The efficiency of two different classification systems based on a dual-side co-occurrence matrix and a single-side co-occurrence matrix has been compared systematically. Our experimental results show that the artificial intelligence system based on a dual-side co-occurrence matrix and back propagation neural network model could achieve a relatively better classification effect, with the high coefficient ratio ( R = 0.9726) when d = 0.

Dual wavelength imaging of a scrape-off layer in an advanced beam-driven field-reversed configuration.

A dual wavelength imaging system has been developed and installed on C-2U to capture 2D images of a He jet in the Scrape-Off Layer (SOL) of an advanced beam-driven Field-Reversed Configuration (FRC) plasma. The system was designed to optically split two identical images and pass them through 1 nm FWHM filters. Dual wavelength images are focused adjacent on a large format CCD chip and recorded simultaneously with a time resolution down to 10 μs using a gated micro-channel plate. The relatively compact optical system images a 10 cm plasma region with a spatial resolution of 0.2 cm and can be used in a harsh environment with high electro-magnetic noise and high magnetic field. The dual wavelength imaging system provides 2D images of either electron density or temperature by observing spectral line pairs emitted by He jet atoms in the SOL. A large field of view, combined with good space and time resolution of the imaging system, allows visualization of macro-flows in the SOL. First 2D images of the electron density and temperature observed in the SOL of the C-2U FRC are presented.

Real-time dual visualization of two different modalities for the evaluation of vocal fold vibration - Laryngeal videoendoscopy and 2D scanning videokymography: Preliminary report.

Currently, various tools have been introduced for the assessment of vocal fold vibration: laryngeal videolaryngoscopy (LV), videokymography (VKG), high speed videoendoscopy (HSV), digital videokymography (DKG), and 2D scanning videokymography (2D VKG). Among these, the authors have recently designed a dual modality examination system using LV and 2D VKG for more detailed information regarding the vibrations of the vocal folds. The clinical availability of this hybrid system offers medical imaging departments a range of potential advantages in the evaluation of vocal fold vibration. The obvious benefit of simultaneous acquisition is the improved integration of information that allows not only optimal anatomic localization, but also physical movement patterns. Other advantages include the lessened inconvenience to patients due to no longer requiring repeated examinations and shortening the examination time, and increased profitability. The purpose of study was to identify the efficacy of real-time dual examination of two different modalities for the evaluation of vocal fold vibration in human subjects and vocal fold vibration simulator. One vocally healthy subject and three patients with vocal fold nodules, a vocal cyst, and vocal fold paralysis took part in this study. The vibratory patterns of the vocal folds were visualized using simultaneous real-time examination of two different modalities. Additionally, qualitative and quantitative analyses of the dual LV and 2D VKG images were performed. Real-time dual examination using a two modality system provided high definition images of the vibratory movements of the vocal folds. By assessing the obtained images, we confirmed that the dual modality examination method was useful in the evaluation of pathologic vibratory patterns, even in non-periodic phonation. The present system might improve the understanding of the processes of vocal fold vibration and make a contribution to pathologic voice research, as well as clinical practice.

A dual approach for machine-awareness in indoor environment combining pseudo-3D imaging and soft-computing techniques

3D spatial characterization of objects is a key-step for autonomous knowledge extraction leading to machine-awareness. In this paper we describe a dual-images-based approach for objects’ 3D characterization and localization for Machine-Awareness in indoor environment. The so-called dual images are provided by color and depth cameras of Kinect system, which presents an appealing potential for 3D objects modeling and localization. Placing the human–machine (including human-robot) interaction as a primary outcome of the intended visual Machine-Awareness in investigated system, we aspire proffering the machine spatial awareness about its surrounding environment with identification and semantically description of relative positions of detected items in that environment. In this research work, the aforementioned pseudo-3D imaging and Soft-computing techniques are combined in order to extract, to recognize and to spatially characterize objects and the distance between objects in 3D environment. In other words, on the one hand, a pseudo-3D object modeling and localization method based on the dual-images of Kinect system is proposed, in which the computation of object’s spatial characterization is presented. On the other hand, a computational semantically description algorithm by using Fuzzy Inference System is proposed, in which the numerical-to-semantic conversion for machine awareness is accomplished. Experimental results validating the investigated approach are reported and discussed.

3D Inspection by Registration of CT and Dual X-ray Images

Computed tomography (CT) can completely digitize the interior and the exterior of nearly any object without any destruction. Generally, the resolution for industrial CT is below a few microns. The industrial CT scanning, however, has a limitation because it requires long measuring and processing time. Whereas, 2D X-ray imaging is fast. In this paper, we propose a novel concept of 3D non-destructive inspection technique using the advantages of both micro-CT and dual X-ray images. After registering the master object&#x2019;s CT data and the sample objects&#x2019; dual X-ray images, 3D non-destructive inspection is possible by analyzing the matching results. Calculation for the registration is accelerated by parallel computing using graphics processing unit (GPU).

Dual time-point 18F-FDG PET/CT to assess response to radiofrequency ablation of lung metastases

AimTo establish the usefulness of dual time-point PET/CT imaging in determining the response to radiofrequency ablation (RFA) of solitary lung metastases from gastrointestinal cancer. Materials and methodsThis prospective study included 18 cases (3 female, 15 male, mean age 71±15 yrs) with solitary lung metastases from malignant digestive tract tumors candidates for RFA. PET/CT images 1h after injection of 4.07MBq/kg of 18F-FDG (standard images) were performed at baseline, 1 month, and 3 months after RFA. PET/CT images 2h after injection centered in the thorax at 1 month after RFA were also performed (delayed images). A retention index (RI) of dual time-point images was calculated as follows: RI=(SUVmax delayed image−SUVmax standard image/SUVmax standard image)*100. Pathological confirmation of residual tumor by histology of the treated lesion was considered as local recurrence. A negative imaging follow-up was considered as complete response. ResultsLocal recurrence was found in 6/18 lesions, and complete response in the remaining 12. The mean percentage change in SUVmax at 1 month and at 3 months showed a sensitivity and specificity for PET/CT of 50% and 33%, and 67% and 92%, respectively. The RI at 1 month after RFA showed a sensitivity and specificity of 83% and 92%, respectively. ConclusionsDual time point PET/CT can predict the outcome at one month after RFA in lung metastases from digestive tract cancers. The RI can be used to indicate the need for further procedures to rule out persistent tumor due to incomplete RFA.

Traveling via Rome through the Stereoscope: Reality, Memory, and Virtual Travel

Underwood and Underwood’s Rome through the Stereoscope of 1902 was a landmark in stereoscopic photography publishing, both as an intense, visually immersive experience and as a cognitively demanding exercise. The set consisted of a guidebook, forty-six stereographs, and five maps whose notations enabled the reader/viewer to precisely replicate the location and orientation of the photographer at each site. Combined with the extensive narrative within the guidebook, the maps and images guided its users through the city via forty-six sites, whether as an example of armchair travel or an actual travel companion. The user’s experience is examined and analyzed within the following parameters: the medium of stereoscopic photography, narrative, geographical imagination, and memory, bringing forth issues of movement, survey and route frames of reference, orientation, visualization, immersion, and primary versus secondary memories. Rome through the Stereoscope was an example of virtual travel, and the process of fusing dual images into one — stereoscopic synthesis — further demarcated the experience as a virtual environment.

SU-G-JeP1-11: Feasibility Study of Markerless Tracking Using Dual Energy Fluoroscopic Images for Real-Time Tumor-Tracking Radiotherapy System

Purpose: The new real-time tumor-tracking radiotherapy (RTRT) system was installed in our institution. This system consists of two x-ray tubes and color image intensifiers (I.I.s). The fiducial marker which was implanted near the tumor was tracked using color fluoroscopic images. However, the implantation of the fiducial marker is very invasive. Color fluoroscopic images enable to increase the recognition of the tumor. However, these images were not suitable to track the tumor without fiducial marker. The purpose of this study was to investigate the feasibility of markerless tracking using dual energy colored fluoroscopic images for real-time tumor-tracking radiotherapy system. Methods: The colored fluoroscopic images of static and moving phantom that had the simulated tumor (30 mm diameter sphere) were experimentally acquired using the RTRT system. The programmable respiratory motion phantom was driven using the sinusoidal pattern in cranio-caudal direction (Amplitude: 20 mm, Time: 4 s). The x-ray condition was set to 55 kV, 50 mA and 105 kV, 50 mA for low energy and high energy, respectively. Dual energy images were calculated based on the weighted logarithmic subtraction of high and low energy images of RGB images. The usefulness of dual energy imaging for real-time tracking with an automated template image matching algorithm was investigated. Results: Our proposed dual energy subtraction improve the contrast between tumor and background to suppress the bone structure. For static phantom, our results showed that high tracking accuracy using dual energy subtraction images. For moving phantom, our results showed that good tracking accuracy using dual energy subtraction images. However, tracking accuracy was dependent on tumor position, tumor size and x-ray conditions. Conclusion: We indicated that feasibility of markerless tracking using dual energy fluoroscopic images for real-time tumor-tracking radiotherapy system. Furthermore, it is needed to investigate the tracking accuracy using proposed dual energy subtraction images for clinical cases.

WE‐FG‐207B‐06: Plaque Composition Measurement with Dual Energy Computed Tomography

Purpose:To investigate the feasibility of characterizing arterial plaque composition in terms of water, lipid and protein or calcium using dual energy computed tomography. Characterization of plaque composition can potentially help distinguish vulnerable from stable plaques.Methods:Simulations studies were performed by the CT simulator based on ASTRA tomography toolbox. The beam energy for dual energy images was selected to be 80 kVp and 135 kVp. The radiation dose and energy spectrum for the CT simulator were carefully calibrated with respect to a 320‐slice CT scanner. A digital chest phantom was constructed using Matlab for calibration and plaque measurement. Pure water, lipid, protein or calcium was used for calibration and a mixture of different volume percentages of these materials were used for validation purposes. Non‐calcified plaque was simulated using water, lipid and protein with volumetric percentage range of 35%∼65%, 5%∼60% and 5%∼40%, respectively. Calcified plaque was simulated using water, lipid and calcium with volumetric percentage range of 50%∼80%, 8%∼45% and 3%∼13%, respectively. We employed iterative sinogram processing (ISP) to reduce the beam hardening effect in the simulation to improve the decomposition results.Results:The simulated known composition and dual energy decomposition results were in good agreement. Water, lipid and protein (calcium) mixtures were decomposed into water, lipid and protein (calcium) contents. The RMS errors of volumetric percentage for the water, lipid and protein (non‐calcified plaque) decomposition, as compared to known values, were estimated to be approximately 5.74%, 2.54%, and 0.95% respectively. The RMS errors of volumetric percentage for the water, lipid and Calcium (calcified plaque) decomposition, as compared to known values, were estimated to be approximately 7.4%, 8.64%, and 0.08% respectively.Conclusion:The results of this study suggest that the dual energy decomposition can potentially be used to quantify the water, lipid, and protein or calcium composition of a plaque with relatively good accuracy.Grant funding from Toshiba Medical Systems and Philips Medical Systems

China and the South China Sea “Lawfare”

The strategic values of the South China Sea had long been recognized. More recently, the South China Sea has once again become an international flashpoint, as disputes take place in the context of a rising and perceived more assertive People’s Republic of China (China) vis-à-vis a relatively declining US that seeks to retain its influence and interests in East Asia. This paper tries to illustrate the growing strategic role of international law in the geopolitics of the South China Sea at play — a subject matter that has so far been less explored — and to assess how the intensified legal maneuvers, or “lawfare” between China on the one hand, and other South China Sea claimants as well as the US on the other, reflect China’s attitude toward the South China Sea dispute and may impact upon the peace and security in the region. It concludes that the “lawfare” since 2009, especially the South China Sea arbitration proceedings initiated by the Philippines, may have not only increased the uncertainties of China’s behavior and China–US relations, but also made the situations in both East and South China seas more complicated. Moreover, China’s responses in the “lawfare” also suggest that China has become more “rule-of-law oriented” as well as hegemonic. The dual images of China raise some uncertainty as to how the South China Sea disputes might eventually be resolved.