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Slicing 3D polygonal meshes is a fundamental operation in various applications such as virtual surgery, garment simulation, and game development. Existing methods primarily slice meshes using either a single line or a set of line segments approximating a smooth curve. This paper introduces a novel approach to freely slice a triangle mesh using a freeform curve without discretizing it into line segments. The user draws a stroke on the screen, defining the desired cutting trajectory. Subsequently, a freeform curve approximating this stroke is generated and extended into a ruled surface in the user’s viewing direction. To efficiently compute intersections between the ruled surface and a triangle mesh, the Line–Surface Intersection (LSI) problem is broken down into two subproblems: Plane–Curve Intersection (PCI) followed by Line–Line Intersection (LLI). Intersection points are then connected to form polylines, effectively cutting the mesh into multiple submeshes. To ensure the solidity of the submeshes, cross-sections are generated by trimming the ruled surface along the polylines and merged with the corresponding submeshes. Our method empowers users to slice triangle meshes along arbitrary trajectories encompassing both straight and freely curved paths while preserving efficiency and accuracy. The effectiveness of the proposed approach is demonstrated through experimental results showing various examples of mesh slicing.

Neurofeedback can be utilized to treat various neuropsychiatric disorders in children. However, therapists primarily set threshold values for neurofeedback training. Thus, the training effect becomes subjective owing to the experience of the therapist. A clinically inexperienced therapist could set inappropriate thresholds, rendering the training ineffective. In this study, an effective neurofeedback system that includes signal processing of large amount of electroencephalogram (EEG) data and auto thresholding and provides various training contents was developed. The system uses a method that determines optimal threshold values, which are significant for an effective neurofeedback system. The success or failure of the activation and inhibition of specific EEG frequencies was determined based on these threshold values. The system determined an optimal threshold value to obtain the target success rate using a numerical optimization technique. The success or failure feedback for the reward and inhibit EEG frequencies was generated using auto thresholding. This feedback was sent to the training contents by the inter-process communication module to control the contents. Most training content was implemented as serious video games by using a commercial game engine. Success feedback on reward EEG frequency leads to game progress. By contrast, failure feedback on inhibiting EEG frequency hinders game progress. Consequently, the user gains the self-regulation ability to enhance the reward EEG frequency and suppress the inhibit EEG frequency. A pilot study involving five children with attention deficiency was conducted to demonstrate the effectiveness of the developed system. The results demonstrated that the childrent’s attention improved after neurofeedback training.

Objectives: To identify and estimate the non-point source (NPS) pollution loads in the Yongdam watershed, and to take an appropriate NPS management plan suitable for the environmental conditions of the sub-basin of Yongdam watershed. Methods: The NPS pollutant loads of the Yongdam watershed was investigated to establish the hydrological simulation program-fortran (HSPF) model for the study area so that the characteristics of non-point runoff were simulated. Furthermore, the detailed catchment area subject to non-point pollution management was selected and the effect of reducing non-point pollution was examined based on the various simulation results. Results and Discussion: The three sub-basins, including specific component of catchments, of Yongdam watershed was selected according to the load intensity and distribution of NPS pollution. The result of analyzing the load flowing into the downstream by rainfall intensity revealed that the pollutant load accounted for 11.8~19.9% in the dry season, and for Jinan-cheon sub-basin the load was high in the range of 10~30 mm while Janggye-cheon sub-basin and downstream of Janggye-cheon junction sub-basin showed a high load in the range 30~60 mm. In addition, the load duration curve (LDC) showed the excess frequency of BOD load was high when the flow rate increased at the end of stream for each sub-basin, whereas the load excess frequency was high in T-P in the entire flow range. LDC analysis led to us that the water quality of stream was affected by point and non-point pollutants in a complex way. When NPS pollution reduction facilities were installed by selecting 10 detailed catchments with high need for NPS pollution management, the reduction of T-P load was estimated to be reduced by 1.85 kg/d in Jinan-cheon sub-basin, 6.40 kg/d in Janggye-cheon sub-basin, and 6.58 kg/d in downstream of Janggye-cheon junction sub-basin. Conclusions: Through various simulation experiments using the HSPF model, it was feasible to select an catchment subject to NPS pollution control in detail and evaluate the effect of reducing NPS pollution.

Due to the outbreak of the SARS-CoV-2 virus, drug repurposing and Emergency Use Authorization have been proposed to treat the coronavirus disease 2019 (COVID-19) during the pandemic. While the efficiency of the drugs has been discussed, it was identified that certain compounds, such as chloroquine and hydroxychloroquine, cause QT interval prolongation and potential cardiotoxic effects. Drug-induced cardiotoxicity and QT prolongation may lead to life-threatening arrhythmias such as torsades de pointes (TdP), a potentially fatal arrhythmic symptom. Here, we evaluated the risk of repurposed pyronaridine or artesunate-mediated cardiac arrhythmias alone and in combination for COVID-19 treatment through in vitro and in silico investigations using the Comprehensive in vitro Proarrhythmia Assay (CiPA) initiative. The potential effects of each drug or in combinations on cardiac action potential (AP) and ion channels were explored using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) and Chinese hamster ovary (CHO) cells transiently expressing cardiac ion channels (Nav1.5, Cav1.2, and hERG). We also performed in silico computer simulation using the optimized O’Hara-Rudy human ventricular myocyte model (ORd model) to classify TdP risk. Artesunate and dihydroartemisinin (DHA), the active metabolite of artesunate, are classified as a low risk of inducing TdP based on the torsade metric score (TMS). Moreover, artesunate does not significantly affect the cardiac APs of hiPSC-CMs even at concentrations up to 100 times the maximum serum concentration (Cmax). DHA modestly prolonged at APD90 (10.16%) at 100 times the Cmax. When considering Cmax, pyronaridine, and the combination of both drugs (pyronaridine and artesunate) are classified as having an intermediate risk of inducing TdP. However, when considering the unbound concentration (the free fraction not bound to carrier proteins or other tissues inducing pharmacological activity), both drugs are classified as having a low risk of inducing TdP. In summary, pyronaridine, artesunate, and a combination of both drugs have been confirmed to pose a low proarrhythmogenic risk at therapeutic and supratherapeutic (up to 4 times) free Cmax. Additionally, the CiPA initiative may be suitable for regulatory use and provide novel insights for evaluating drug-induced cardiotoxicity.

Objectives To evaluate the difference between healthcare professionals (HCPs) and adults with spinal cord injury (SCI) in Asia regarding knowledge and interpretation of ‘exercise intensity’ for aerobic exercise prescription.Methods and study design A survey was distributed to practising HCP and adults with SCI. It was completed in participants’ local language on topics related to the importance of exercise frequency, intensity, time and type; methods for monitoring and terms related to exercise intensity prescription. χ2 analysis was used to detect differences in HCP or those with SCI.Results 121 HCP and 107 adults with an SCI ≥1 years (C1–L4) participated. Responses revealed 61% of all HCP ranked ‘intensity’ being most important whereas only 38% respondents from the SCI group ranked it as high importance (p=0.008). For those with SCI, ‘frequency’ was most important (61%) which was significantly higher than the 45% selected by HCPs (p=0.030). Of the 228 respondents on average only 34% believed that the terms, ‘moderate’ and ‘vigorous’ provided enough information for aerobic exercise intensity prescription. HCP most often used HR methods compared with the SCI group (90% vs 54%; p

Abstract Background Dyspnea is a common symptom in patients presenting to the emergency department. It has a variety of causes that range from non-urgent to life-threatening. One episode of dyspnea in a healthy young person is easy to overlook. However, if the symptoms occur after physically or emotionally stressful events, careful evaluation needs to be undertaken because it may be associated with Takotsubo syndrome, which is rarely expected but can be fatal. Herein, we report the case of Takotsubo syndrome in a healthy young woman who arrived at the emergency department after experiencing a short single episode of dyspnea following a minor surgery. Case presentation A 23-year old woman with no underlying chronic disease underwent closed reduction surgery for a nasal bone fracture under general anesthesia (with sevoflurane as the anesthetic). Approximately 5 h later, she presented to the emergency department with dyspnea, which improved soon upon arrival at the emergency department. There were no other symptoms. The dyspnea occurred about 5 h after being discharged on observation, with an uneventful postoperative course. Her electrocardiogram and chest X-ray findings were unremarkable. On testing, troponin I and creatine kinase myocardial band levels were elevated at 6.122 ng/mL and 11.2 µg/L (reference ranges: 0.000–0.046 ng/mL and 0.0–5.0 µg/L), respectively. Bedside echocardiography revealed an ejection fraction of 25%, with mid-ventricular and apical akinesia and basal hyperkinesia. The pulmonary and coronary angiographic computed tomographic scans were unremarkable. Hence, apical Takotsubo syndrome was suspected. A follow-up echocardiogram taken 5 days after admission showed full recovery with a normalized ejection fraction (60%) and no regional wall motion abnormality. The patient was discharged on the sixth day with no other complications. Conclusion When atypical symptoms, such as transient dyspnea, manifest, it becomes necessary to suspect and diagnose Takotsubo syndrome to ensure timely and appropriate medical management, especially when a preceding stressful event, such as minor surgery has occurred. It might be helpful to perform bedside point-of-care echocardiography to check for regional wall motion abnormalities that are typically associated with Takotsubo syndrome.

Objective Bilateral frozen shoulder (FS) is often treated with intra-articular corticosteroid injection (IACI). No studies have been performed to establish whether IACI must be administered in both shoulders or in only one shoulder to improve function. This study was therefore performed to determine whether unilateral IACI improves shoulder pain and passive range of motion (pROM) in bilateral FS. Methods The medical records of 165 patients with bilateral primary FS who underwent ultrasonography-guided IACI (2 mL of 10-mg/mL triamcinolone acetonide mixed with 5 mL of 1% lidocaine) in one shoulder were retrospectively reviewed. The outcome measures, namely the numeric rating scale (NRS) scores and pROM values (abduction, external rotation, flexion, hyperextension, and internal rotation), were evaluated pre- and post-injection. Results The patients’ mean age was 54.0 ± 8.0 years. The mean symptom duration was 6.5 ± 2.8 months. The mean follow-up period after injection was 6.7 ± 0.8 weeks. The NRS scores and pROM values significantly improved in both the injected and non-injected shoulders. Conclusions This study showed that unilateral IACI in patients with bilateral FS improves the clinical outcome of the non-injected shoulder. We suggest that physicians observe the non-injected shoulder after unilateral injection rather than performing bilateral injections.

A shape detail transfer is the process of extracting the geometric details of a source region and transferring it onto a target region. In this paper, we present a simple and effective method, called GeoStamp, for transferring shape details using a Poisson equation. First, the mean curvature field on a source region is computed by using the Laplace–Beltrami operator and is defined as the shape details of the source region. Subsequently, the source and target regions are parameterized on a common 2D domain, and a mean curvature field on the target region is interpolated by the correspondence between two regions. Finally, we solve the Poisson equation using the interpolated mean curvature field and the Laplacian matrix of the target region. Consequently, the mean curvature field of the target region is replaced with that of the source region, which results in the transfer of shape details from the source region to the target region. We demonstrate the effectiveness of our technique by showing several examples and also show that our method is quite useful for adding shape details to a surface patch filling a hole in a triangular mesh.

Curves on a polygonal mesh are quite useful for geometric modeling and processing such as mesh-cutting and segmentation. In this paper, an effective method for constructing C1 piecewise cubic curves on a triangular mesh M while interpolating the given mesh points is presented. The conventional Hermite interpolation method is extended such that the generated curve lies on M. For this, a geodesic vector is defined as a straightest geodesic with symmetric property on edge intersections and mesh vertices, and the related geodesic operations between points and vectors on M are defined. By combining cubic Hermite interpolation and newly devised geodesic operations, a geodesic Hermite spline curve is constructed on a triangular mesh. The method follows the basic steps of the conventional Hermite interpolation process, except that the operations between the points and vectors are replaced with the geodesic. The effectiveness of the method is demonstrated by designing several sophisticated curves on triangular meshes and applying them to various applications, such as mesh-cutting, segmentation, and simulation.

A triangular mesh obtained by scanning 3D models typically contains holes. We present an effective technique for filling a hole in a triangular mesh in geometric modeling. Simple triangulation of a hole is refined and remeshed iteratively to generate an initial patch. The generated patch is then enhanced to become a target patch by minimizing the variation of principal curvatures. In discrete approximation, this produces a third-order Laplacian system of sparse symmetric positive definite matrix, and the symmetry can efficiently be used to find the robust solutions to the given Laplacian system. Laplacian smoothing of the target patch is defined as a source patch. The shape difference between two corresponding vertices of the source and the target patches is measured in terms of Euclidean distance and curvature variation. On the basis of the shape difference and a user-specified control parameter, different blending weights are determined for each vertex, and the final patch is generated by blending two patches. We demonstrate the effectiveness of our technique by discussing several examples. The experimental results show that our technique can effectively restore salient geometric features of the original shape.

Purpose: To demonstrate the superficial hyperechoic band (SHEB) in articular cartilage by using ultrasonography (US) and to assess its correlation with histological images. Methods: In total, 47 regions of interest (ROIs) were analyzed from six tibial osteochondral specimens (OCSs) that were obtained after total knee arthroplasty. Ultrasonograms were obtained for each OCS. Then, matching histological sections from all specimens were obtained for comparison with the ultrasonograms. Two types of histological staining were used: Safranin-O stain (SO) to identify glycosaminoglycans (GAG) and Masson’s trichrome stain (MT) to identify collagen. In step 1, two observers evaluated whether there was an SHEB in each ROI. In step 2, the two observers evaluated which histological staining method correlated better with the SHEB by using the ImageJ software. Results: In step 1 of the analysis, 20 out of 47 ROIs showed an SHEB (42.6%, kappa=0.579). Step 2 showed that the SHEB correlated significantly better with the topographical variation in stainability in SO staining, indicating the GAG distribution, than with MT staining, indicating the collagen distribution (P

We present a new method for constructing a parametric blending surface that smoothly connects two triangular meshes. A user selects a subregion on each triangular mesh. The local parameterizations of two selected regions are found by using geodesic polar coordinates, and a base surface on each triangular mesh is constructed by two boundary curves on parametric domain. Finally, two base surfaces are smoothly blended for generating a blending surface. The shape of a blending surface can easily be controlled by several shape parameters or by directly manipulating surface point. We demonstrate the effectiveness of our technique by showing several modeling examples.

We propose a new tangible visualization table for intuitive and effective visualization of terrain data transferred from a remote server in real time. The shape display approximating the height field of remote terrain data is generated by linear actuators, and the corresponding texture image is projected onto the shape display. To minimize projection distortions, we present a sophisticated technique for projection mapping. Gesture-based user interfaces facilitate intuitive manipulations of visualization results. We demonstrate the effectiveness of our system by displaying and manipulating various terrain data using gesture-based interfaces.

We facilitate the editing of hierarchical B-spline curves at multiple resolutions by expressing a displacement function at each level in rotation minimizing frames (RMFs) on the curve at the next lower level. When the curve is edited at a particular level, RMFs at all the higher levels are updated, and the control points of the displacement function at each higher level are obtained from these new RMFs. This transfers details created at the current level to higher levels. Our method presents a hundred-fold faster way to reflect editing results compared to the traditional approach using Frenet frames. We demonstrate the effectiveness of our technique by showing several examples of editing curves with fine details.

An efficient surface area evaluation method is introduced by using smooth surface reconstruction for three-dimensional scanned human body data. Surface area evaluations for various body parts are compared with the results from the traditional alginate-based method, and quite high similarity between the two results is obtained. We expect that our surface area evaluation method can be an alternative to measuring surface area by the cumbersome alginate method.

PN (point-normal) triangles are cubic Bézier triangles which meet at their edges to surface a triangular mesh, but this only achieves G0 continuity. We define blending regions that span the edges shared by adjacent pairs of triangular domains and blend the corresponding Bézier triangles using a univariate blending function formulated in terms of barycentric coordinates. This produces G2 continuity across boundaries while preserving G1 continuity at vertices. The sharpness of the blends can be controlled locally by varying the extent of these blending regions. We demonstrate the effectiveness of our technique by showing several modeling examples.

We present a method for transferring deformation weights of a human character to three-dimensional (3D) scanned clothes. First, clothing vertices are projected onto a character skin. Their deformation weights are determined from the barycentric coordinates of the projection points. For more complicated parts, such as shoulders and armpits, continuously moving planes are constructed and employed as projection reference planes. Clothing vertices on a plane are projected onto the intersection curve of the plane with a character skin to achieve a smooth weight transfer. The proposed method produces an initial deformation for physically based clothing simulations. We demonstrated the effectiveness of our method through several deformation results for 3D scanned clothes. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to evaluate the activity of rotator cuff (RC) muscles during activities of daily living. Design: Motion analysis was conducted with 14 volunteers. Activation of RC (subscapularis, supraspinatus, and infraspinatus) was assessed using electromyography (EMG). Walking was performed with or without a shoulder immobilizer. Eating was conducted with or without the support of the elbow with the contra-lateral hand. Washing the hair was simulated while standing or leaning forward; washing the body was simulated while standing or holding the elbow; and washing the face was simulated using both hands while leaning forward. Results: During walking, RC's peak EMG activities remained below 7% maximum voluntary isometric contraction at all times, regardless of the use of immobilizers. Eating caused mild EMG activities (14%-32%), whereas eating with elbow support resulted in significantly lower EMG activities in the supraspinatus and infraspinatus. Washing the hair standing moderately activated RC (23%-57%), whereas leaning forward decreased it to 6% to 36%. Washing the body while holding the elbow decreased infraspinatus activation to 4% from 10% when standing. Washing the face with both hands and leaning forward resulted in high-peak EMG activities in the upper subscapularis (37%). Conclusions: There was no difference in RC activity level between walking with or without immobilizers. From the point of muscle contraction, an immobilizer is not mandatory. Holding the elbow with the contralateral hand while eating or washing can help decrease the load in the supraspinatus and infraspinatus. [ABSTRACT FROM AUTHOR]

Porcine circovirus type 2 (PCV2) is the primary causative agent for post-weaning, multisystemic, wasting syndrome. Consequently, serologic detection of and vaccination against PCV2 are important for the swine industry. Among several serological tests, the enzyme-linked immunosorbent assay (ELISA) is commonly used to measure anti-PCV2 antibody levels. In the present study, we used two commercial ELISA systems to comparatively evaluate anti-PCV2 antibodies in field pigs treated with three different PCV2 vaccines. Among a total of 517 serum samples, the results of the two ELISAs were fully concordant for 365 positive and 42 negative samples, indicating 78.7% agreement. In addition, the Pearson coefficient (0.636) indicated a moderate correlation between data from the two ELISAs. Results from the farms with pigs vaccinated with the three different PCV2 vaccines demonstrated that most of the vaccinated animals underwent seroconversion. However, the increase and duration of antibody titers varied depending on the vaccine, the presence of maternal antibodies, and the vaccination program. PCV2 serologic status and anti-PCV2 antibody levels of herds from this study could be utilized to determine the best timing for vaccination and assessing vaccination compliance. [ABSTRACT FROM AUTHOR]

Highlights: [•] We propose Fanning factor and Nusselt number correlations for the airfoil PCHE. [•] We evaluate the thermal–hydraulic performance for each PCHE type in terms of the total cost. [•] The zigzag PCHE is the most appropriate IHX for the HTGRs, operating in laminar region. [•] The straight PCHE is the best for the IHX in the SFRs, operating in turbulent region. [Copyright &y& Elsevier]

We present a new method for generating sweep surfaces using bivariate B-spline motion. The sweep surface is defined as the trace of a single point under bivariate B-spline motion. Direct manipulation of the sweep surface is achieved by controlling its motion components while producing various editing effects. We demonstrate the effectiveness of our technique by modeling and deforming various three-dimensional shapes. [ABSTRACT FROM AUTHOR]

Recently, novel application areas in digital geometry processing, such as simulation, dynamics, and medical surgery simulations, have necessitated the representation of not only the surface data but also the interior volume data of a given 3D object. In this paper, we present an efficient framework for the shape approximations of spherical solid objects based on trivariate B-splines. To do this, we first constructed a smooth correspondence between a given object and a unit solid cube by computing their harmonic mapping. We set the unit solid cube as a rectilinear parametric domain for trivariate B-splines and utilized the mapping to approximate the given object with B-splines in a coarse-to-fine manner. Specifically, our framework provides user-controllability of shape approximations, based on the control of the boundary condition of the harmonic parameterization and the level of B-spline fitting. Experimental results showed that our method is efficient enough to compute trivariate B-splines for several models, each of whose topology is identical to a solid sphere. [ABSTRACT FROM AUTHOR]

This study investigated the effects of high exhaust gas recirculation (EGR) rates on dimethyl ether (DME) fuel combustion performance, exhaust emissions and particle emission characteristics in a small direct injection diesel engine under various injection timings. To examine the effect of EGR and injection timings, the experiment was performed under high EGR rates (0%, 30%, 50%) and injection timings were varied from 40° before top dead center (BTDC) to top dead center (TDC) of the crank angle to examine the effects of early injection of DME fuel. The combustion pressures and heat release rates for different EGR rates followed similar trends. As the injection timing was advanced, the indicated mean effective pressure (IMEP) differed little in response to EGR rate in the range from TDC to 25° BTDC, and more for crank angles beyond 25° BTDC. DME combustion exhibited very little soot emission, but soot emission increased slightly with EGR rate. The use of high EGR during combustion produced very low NOx concentrations but increased HC and CO emissions for advanced injection timings from 25° BTDC to 40° BTDC. The use of EGR increased both the emissions of total particle number and particle volume over the whole range of the injection timings; for all cases, total particle volume decreased as injection timing was advanced. [ABSTRACT FROM AUTHOR]

There are a growing number of ethnic restaurants in the UK and many factors influence which restaurant a consumer chooses. This study explores the factors influencing people's choice of Korean food in the UK and the results can lead to a better understanding of how to increase the awareness of people to Korean foods. Ten face-to-face interviews were conducted and 170 surveys completed by consumers who had experienced a Korean restaurant in the UK. The study discovered the significant differences in many factors, particularly between ages and genders. The study can contribute for ethnic restaurateurs in the UK who needs to investigate diverse segmentation of customer's behavior and preference in order to stay competitive in the market. [ABSTRACT FROM AUTHOR]

We present a compact representation for the bounding volume hierarchy (BVH) of freeform NURBS surfaces using Coons patches. Following the Coons construction, each subpatch can be bounded very efficiently using the bilinear surface determined by the four corners. The BVH of freeform surfaces is represented as a hierarchy of Coons patch approximation until the difference is reduced to within a given error bound. Each leaf node contains a single Coons patch, where a detailed BVH for the patch can be represented very compactly using two lists (containing curve approximation errors) of length proportional only to the height of the BVH. We demonstrate the effectiveness of our compact BVH representation using several experimental results from real-time applications in collision detection and minimum distance computation for freeform models. [ABSTRACT FROM AUTHOR]

We construct surfaces with darts, creases, and corners by blending different types of local geometries. We also render these surfaces efficiently using programmable graphics hardware. Points on the blending surface are evaluated using simplified computation which can easily be performed on a graphics processing unit. Results show an eighteen-fold to twenty-fold increase in rendering speed over a CPU version. We also demonstrate how these surfaces can be trimmed using textures. [ABSTRACT FROM AUTHOR]

An experimental investigation was performed to analyze the effects of biodiesel-ethanol blended fuel spray on the combustion, and exhaust emission characteristics in a single cylinder common-rail diesel engine. In order to analyze the macroscopic and microscopic characteristics of biodiesel blended fuel spray, parameters, such as injection rate, droplet diameters, and spray tip penetration, were measured using an injection rate meter system, spray visualization, and droplet measuring system. Also, measurements of combustion, exhaust emissions, and size distributions of particulate matter were carried out under various engine operating conditions for biodiesel-ethanol blends and the results were compared with those of conventional diesel fuel. In this investigation, the measured results of biodiesel-ethanol blended fuel show that the Sauter mean diameter decreased with the increase of relative velocity between the injected fuel and the ambient gas. Comparing the combustion characteristics of diesel fuel and biodiesel-ethanol blended fuels, both diesel and blended fuel show similar trends of combustion pressure and rate of heat release. However the combustion of biodiesel-ethanol blends indicated lower combustion characteristics, such as combustion pressures and heat release rates, than those of diesel fuel because of its lower heating value. In the case of exhaust gas recirculation, the indicated specific NOx (ISNOx) and soot concentration results showed lower emissions compared with those of conventional diesel fuel. [ABSTRACT FROM AUTHOR]

To use three-dimensional (3D) laser scanning to elucidate changes in the external facial contour before and after botulinum toxin type A (BoNT-A) injections. BoNT-A was injected into 15 volunteers as a treatment for lower facial contouring. A total of 25 U of BoNT-A was injected into each side of the masseter muscle bilaterally. On each side, it was injected into two points at the center of the lower third of the masseter muscle separated by 1 cm. The clinical effects of BoNT-A were evaluated by performing 3D laser scans before and 4, 8, 12, and 24 weeks after the injection. The mean values of the volume and widths of the most prominent area at each time point differed significantly before and 4, 8, 12, and 24 weeks after the injection. The volumes and widths of the most prominent areas of the lower face (masseter muscle) were significantly lower 4, 8, 12, and 24 weeks after injecting BoNT-A than before the injection. The mean values of the volume and widths of the most prominent area were 2,176.93 mm and 2.39 mm less, respectively, 24 weeks after the injection than before. The authors have indicated no significant interest with commercial supporters. [ABSTRACT FROM AUTHOR]

We present a real-time algorithm for computing the precise Hausdorff Distance (HD) between two planar freeform curves. The algorithm is based on an effective technique that approximates each curve with a sequence of G1 biarcs within an arbitrary error bound. The distance map for the union of arcs is then given as the lower envelope of trimmed truncated circular cones, which can be rendered efficiently to the graphics hardware depth buffer. By sampling the distance map along the other curve, we can estimate a lower bound for the HD and eliminate many redundant curve segments using the lower bound. For the remaining curve segments, we read the distance map and detect the pixel(s) with the maximum distance. Checking a small neighborhood of the maximum-distance pixel, we can reduce the computation to considerably smaller subproblems, where we employ a multivariate equation solver for an accurate solution to the original problem. We demonstrate the effectiveness of the proposed approach using several experimental results. [ABSTRACT FROM AUTHOR]

Background: The proximal tibiofibular joint (PTFJ) can be considered the fourth compartment of the knee joint. However, there have been no studies of the T2 values (T2 relaxation time) of PTFJ cartilage. Purpose: To assess the T2 values of PTFJ cartilage at 3T magnetic resonance imaging (MRI), and to show the clinical utility of T2 values of PTFJ cartilage for the diagnosis of osteoarthritis (OA). Material and Methods: 118 patientswho had knee MR imaging and knee radiography were enrolled. MRI was performed using a 3T MRI scanner, and T2 maps were calculated from a sagittal multi-echo acquisition. Two regions of interest (ROIs) were positioned within PTFJ cartilage and medial femoral condyle (MFC) cartilage. The average T2 value and standard deviation (SD) of each ROI were recorded. Using PTFJ cartilage asa standard reference, the T2 index ((MFC/PTFJ)x100) and T2SD index ((MFCSD/PTFJSD)x100) were calculated. A paired t test was performed to compare the mean and SD of ROIswithin PTFJ and MFC cartilage. Correlation analyseswere performed among the parametersage, Kellgren-Lawrence (KL) score, means and SDs of ROIswithin PTFJ and MFC cartilage, T2 index, and T2SD index. Results: PTFJ cartilage had a significantly shorter T2 value than did MFC cartilage (P< 0.0001). ROIs within PTFJ cartilage showed significantly smaller SDs than did those within MFC cartilage (P<0.0001). The average T2 value and SD of MFC and the T2SD index showed a positive correlation to the KL score (P<0.05). The correlation coefficientsfor the average T2 value, SD, and T2SD index of MFC were R=0.203, 0.254, and 0.268, respectively. However, there was no significant correlation between T2 valuesof PTFJ cartilage and KL score (P=0.643). Conclusion: PTFJ cartilage showed shorter and more homogeneous T2 values with a small SD than did MFC cartilage, regardless of the degree of OA at femorotibial compartments. PTFJ cartilage may be a useful internal standard reference to diagnose OA and would be a good candidate asa standard reference for cartilage imaging. [ABSTRACT FROM AUTHOR]

We present a layered geometric approach to the skinning of character animation. On top of a global shape deformation, B-spline surface patches are attached to various body parts for local control. The patches are directly manipulated so as to generate example local shapes at some important poses. During character animation, the B-spline control points move continuously by kinematically interpolating a set of example patches, and at the same time they can also move dynamically by elastic simulation. The movement of control points changes the shape of a local patch, and consequently skin vertices move according to the patch deformation, finally generating the desired local deformation. We demonstrate the effectiveness of our approach by generating natural local details at various poses including muscular effects and elastic deformation. Moreover, dealing with only a small number of control points, the proposed method is very efficient, while generating hundreds to thousands frames per second. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An experimental investigation was performed on the effect of engine speed, exhaust gas recirculation (EGR), and boosting intake pressure on the particulate size distribution and exhaust gas emissions in a compression ignition engine fueled with biodiesel derived from soybean. The results obtained by biodiesel fuel were compared to those obtained by petroleum diesel fuel with a sulfur content of 16.3 ppm. A scanning mobility particulate sizer was used for size distribution analysis, and it measured mobility equivalent particulate diameter in the range of 10.4-392.4 nm. In addition to the size distribution of the particulates, exhaust emissions, such as oxides of nitrogen (NOx), hydrocarbon, and carbon monoxide emissions, and combustion characteristics under different engine operating parameters were investigated. The engine operating parameters in terms of engine speed, EGR, and intake pressure were varied to investigate their individual impacts on the combustion and exhaust emission characteristics. As the engine speed was increased for both fuels, the larger size particulates, which dominantly contribute particulate mass, were increased; however, total numbers of particulate were reduced. Compared to diesel fuel, the combustion of biodiesel fuel reduced particulate concentration of relatively larger size where most of the particulate mass is found. Moreover dramatically lower hydrocarbon and carbon monoxide emissions were found in the biodiesel-fueled engine. However the NOx emission of the biodiesel-fueled diesel engine shows slightly higher concentration compared to diesel fuel at the same injection timing. EGR significantly increased the larger size particulates, which have diameter near the maximum measurable range of the instrument; however the total number of particulates was found not to significantly increase with increasing EGR rate for both fuels. Boosting intake pressure shifted the particulate size distribution to smaller particulate diameter and effective reduction of larger size particulate was found for richer operating conditions. [ABSTRACT FROM AUTHOR]

We propose a sweep-based approach to the freeform deformation of three-dimensional objects. Instead of using a volume enclosing the whole object, we approximate only its deformable parts using sweep surfaces. The vertices on the object boundary are bound to the sweep surfaces and follow their deformation. Several sweep surfaces can be organized into a hierarchy so that they interact with each other in a controlled manner. Thus we can support intuitively plausible shape deformation of objects of arbitrary topology with multiple control handles. A sweep-based approach also provides important advantages such as volume preservation. We demonstrate the effectiveness of our technique in several examples. Categories and Subject Descriptors (according to ACM CCS): I.3.5 [Computational Geometry and Object Modeling]: Curve, surface, solid, and object representations [ABSTRACT FROM AUTHOR]

We present a new approach to realistic hand modeling and deformation with real-time performance. We model the underlying shape of a human hand by means of sweeps which follow a simplified skeleton. The resulting swept surfaces are blended, and an auxiliary surface is then bound to the swept representation in the palm region. In the areas of this palm-control surface where bulges occur in certain poses of a real hand, the vertices are given their own trajectories, so that the palm forms realistic shapes as the joints bend. Palm lines can also be modeled as valleys in the skin by sketching them on a displacement map on the palm-control surface, and activitating them when appropriate joint movements take place. Self-intersections and collisions are detected using geometric primitives that are automatically generated from, and deform with, the sweeps and palm surface. Our algorithm runs in real time, and the naturalism of its results are demonstrated by comparative images of modeled and real hands, including several challenging poses. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract We present a sweep-based approach to human body modeling and deformation. A rigid 3D human model, given as a polygonal mesh, is approximated with control sweep surfaces. The vertices on the mesh are bound to nearby sweep surfaces and then follow the deformation of the sweep surfaces as the model bends and twists its arms, legs, spine and neck. Anatomical features including bone-protrusion, muscle-bulge, and skin-folding are supported by a GPU-based collision detection procedure. The volumes of arms, legs, and torso are kept constant by a simple control using a volume integral formula for sweep surfaces. We demonstrate the effectiveness of this sweep-based human deformation in several test animation clips. [ABSTRACT FROM AUTHOR]

Nearly spherical Au nanoparticles of about 3.83 nm diameter were embedded into the (Ba,Sr)TiO3 matrix using alternating sputtering method, showing the characteristic surface plasmon resonance absorption band at 571 nm. Dispersion in the third-order optical nonlinearity was investigated at several wavelengths from 450 to 680 nm around the resonance peak by a single beam Z-scan technique with a wavelength tunable picosecond laser system. The real and imaginary parts of third-order nonlinear susceptibility were resolved and the relative contributions are quantitatively compared at each wavelength. The maximum absolute value of third-order susceptibility as large as 4.312 × 10-8esu was obtained at the surface plasmon frequency. The temporal response was also characterized by the femtosecond time-resolved optical Kerr gate measurement and the nonlinear response time was evaluated to be 192 fs at the laser wavelength of 800 nm. [ABSTRACT FROM AUTHOR]

An experimental investigation was performed on the effect of injection strategy on the combustion, exhaust emission characteristics and the particle size distribution in a small direct-injection (DI) compression ignition engine fueled with a biodiesel-ethanol blended fuel. The results obtained from the experiment of the particle distributions for the blended fuel are compared with that of diesel fuel. in addition to the distribution of the particles, exhaust emissions, such as oxides of nitrogen (NOx), hydrocarbon (HC), and carbon monoxide (CO) emissions, and combustion characteristics under different injection parameters were investigated. The injection parameters in terms of first injection mass and second injection mass were varied to investigate the combustion and emission reduction in the biodiesel and ethanol blended fuel. The results show that the first combustion and heat release generated from the first injection, and then the second injected fuel rapidly combusted with an extremely short ignition delay. The maximum combustion pressures and heat releases of a biodiesel-eihanol blend are generally higher than those of the ultra-low sulfur diesel (ULSD) in all cases, regardless ~f an equal quantity offuel is injected. The soot and NOx emissions for a blend are relatively lower than the ULSD at all test ranges. in addition, HC and CO emissions for a blend also indicated relatively low levels compared with those of the ULSD. Double injection cases for biodiesel-ethanol blend, the number concentrations of larger size particles which are closely related to the weight of smoke emissions mass were significantly reduced. [ABSTRACT FROM AUTHOR]