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We propose a descattering method that can be easily applied to food production lines. The system consists of several sets of linear image sensors and linear light sources slanted at different angles. The images captured by these sensors are partially clear along the direction perpendicular to the sensors. We computationally integrate these images on the frequency domain into a single clear image. The effectiveness of the proposed method is assessed by simulation and real-world experiments. The results show that our method recovers clear images. We demonstrate the applicability of the proposed method to a real production line by a prototype system.

We propose a method for eliminating the temporal illumination variations in whisk-broom (point-scan) hyperspectral imaging. Whisk-broom scanning is useful for acquiring a spatial measurement using a pixel-based hyperspectral sensor. However, when it is applied to outdoor cultural heritages, temporal illumination variations become an issue due to the lengthy measurement time. As a result, the incoming illumination spectra vary across the measured image locations because different locations are measured at different times. To overcome this problem, in addition to the standard raster scan, we propose an additional perpendicular scan that traverses the raster scan. We show that this additional scan allows us to infer the illumination variations over the raster scan. Furthermore, the sparse structure in the illumination spectrum is exploited to robustly eliminate these variations. We quantitatively show that a hyperspectral image captured under sunlight is indeed affected by temporal illumination variations, that a Naïve mitigation method suffers from severe artifacts, and that the proposed method can robustly eliminate the illumination variations. Finally, we demonstrate the usefulness of the proposed method by capturing historic stained-glass windows of a French cathedral.

Although the prognosis of patients with extramammary Paget's disease (EMPD) treated with radical resection is good, the prognosis of EMPD with distant metastasis is very poor. PIK3CA mutations predict a good response to PIK3CA inhibitors. The aim of this study was to investigate the occurrence rate of PIK3CA mutations (including multiple mutations [MM]) related to the intertumor and intratumor heterogeneity in EMPD and to evaluate the correlation between these mutations and clinical parameters of EMPD. We performed droplet digital polymerase chain reaction to detect PIK3CA mutations (E542K, E545K, H1047R, and MM) in 68 patients with EMPD. In addition, we investigated the presence of PIK3CA mutations at multiple sites in 16 patients with PIK3CA mutations to assess the intratumor heterogeneity of PIK3CA mutations in EMPD. The frequency of one or more PIK3CA mutations in patients with EMPD was 30.8% (21/68). The frequency of E542K, E545K, H1047R, and MM were 10.2% (7/68), 13.2% (9/68), 11.7% (8/68), and 4.4% (3/68), respectively. No significant correlation was found between PIK3CA mutation patterns and clinical parameters. Of the 21 patients with PIK3CA mutations, 16 with tissue samples that could be analyzed at multiple sites were examined. The proportion of patients with the same PIK3CA mutations at all sites was 12.5% (2/16). The proportion of patients with the same PIK3CA mutations at least two or more sites, but not at all sites, was 31.2% (5/16). The proportion of patients with no PIK3CA mutations at other sites was 37.5% (6/16). The proportion of patients with other PIK3CA mutations at other sites was 18.7% (3/16). There is intertumor and intratumor heterogeneity of PIK3CA mutations. PIK3CA mutations in EMPD may be progressor mutations in EMPD.

We propose a time-of-flight measurement algorithm for depth and intensity that is robust to fog. The key idea of the algorithm is to compensate for the scattering effects of fog by using multiple time-gating and assigning one time-gated exposure for scattering property estimation. Once the property is estimated, the depth and intensity can be reconstructed from the rest of the exposures via a physics-based model. Several experiments with artificial fog show that our method can measure depth and intensity irrespective of the traits of the fog. We also confirm the effectiveness of our method in real fog through an outdoor experiment.

The recent development of 3D printing technology has brought concerns about its potential misuse, such as in copyright infringement, and crimes. Although there have been many studies on blind 3D mesh watermarking for the copyright protection of digital objects, methods applicable to 3D printed objects are rare. In this paper, we propose a novel blind watermarking algorithm for 3D printed objects with applications for copyright protection, traitor tracing, object identification, and crime investigation. Our method allows us to embed a few bits of data into a 3D-printed object, and retrieve it by 3D scanning without requiring any information about the original mesh. The payload is embedded on the object's surface by slightly modifying the distribution of surface norms, that is, the distance between the surface, and the center of gravity. It is robust to resampling and can work with any 3D printer, and scanner technology. In addition, our method increases the capacity, and resistance by subdividing the mesh into a set of bins, and spreading the data over the entire surface to negate the effect of local printing artifacts. The method's novelties include extending the vertex norm histogram to a continuous surface, and the use of 3D moments to synchronize a watermark signal in a 3D-printing context. In the experiments, our method was evaluated using a public dataset against center, orientation, minimum, and maximum norm misalignments; a printing simulation; and actual print/scan experiments using a standard 3D printer, and scanner.

Walking is one of the most important activities in daily living, and difficulty walking presents a severe limitation. In this study, we develop shoes with elastomer-embedded flexible joints (EEFJ) that assist the tibialis anterior in its function during the initial stance and swing phase of the gait cycle. The EEFJ designed is suitable for shoes, with an adjustment mechanism incorporated for easy adjustment. To assess the ease of wearing, we measured the time it took four elderly subjects to wear the shoes for the first time. The donning time was less than one minute for all four participants. Furthermore, no one indicated discomfort when they walked naturally with the shoes. The supporting effect of the EEFJ shoes was assessed for ten healthy male subjects walking with their ankles relaxed. Statistical analysis reveals significant differences in the ankle at initial contact (p=0.02) and maximum plantar flexion (p=0.03). The average angle at initial contact while wearing the EEFJ shoes is 5.3° less than without it, and the average maximum plantar flexion is 5.1° less than without the shoes.

Coupling supercritical fluid extraction (SFE) on-line with supercritical fluid chromatography (SFC) - tandem mass spectrometry (MS/MS) provides a single platform for efficient extraction, separation, and detection in a chemical analysis. SFE-SFC-MS/MS requires consideration of many extraction and chromatographic variables to not only provide the most efficient extraction, but also to analytically transfer the extracted analytes to the column for separation. There is a fundamental lack of understanding of how the variables in SFE affect those in SFC. Typically, a univariate approach is taken in on-line SFE-SFC-MS/MS method development, but this provides little insight into the relative importance of variables and their potential interactions. Here, a multivariate approach was used to develop a better understanding of the synergistic relationship between the extraction and separation processes by focusing on the optimization of extraction parameters for target analytes with a wide range of physicochemical properties in matrices of variable retentivity. The methodology used a set of optimal on-line SFE-SFC-MS/MS extraction parameters for 18 analytes of variable physicochemical properties in three different silica gel-based sample matrices are presented.

We construct approximate Fekete point sets for kernel-based interpolation by maximising the determinant of a kernel Gram matrix obtained via truncation of an orthonormal expansion of the kernel. Uniform error estimates are proved for kernel interpolants at the resulting points. If the kernel is Gaussian, we show that the approximate Fekete points in one dimension are the solution to a convex optimisation problem and that the interpolants converge with a super-exponential rate. Numerical examples are provided for the Gaussian kernel.

Phase ambiguity is a major problem in the depth measurement in either time-of-flight or phase shifting. Resolving the ambiguity using a low frequency pattern sacrifices the depth resolution, and using multiple frequencies requires a number of observations. In this paper, we propose a phase disambiguation method that combines temporal and spatial modulation so that the high depth resolution is preserved while the number of observation is kept. A key observation is that the phase ambiguities of temporal and spatial domains appear differently with respect to the depth. Using this difference, the phase can disambiguate for a wider range of interest. We develop a prototype to show the effectiveness of our method through real-world experiments.

This paper presents a material classification method using an off-the-shelf Time-of-Flight (ToF) camera. The proposed method is built upon a key observation that the depth measurement by a ToF camera is distorted for objects with certain materials, especially with translucent materials. We show that this distortion is due to the variation of time domain impulse responses across materials and also due to the measurement mechanism of the ToF cameras. Specifically, we reveal that the amount of distortion varies according to the modulation frequency of the ToF camera, the object material, and the distance between the camera and object. Our method uses the depth distortion of ToF measurements as a feature for classification and achieves material classification of a scene. Effectiveness of the proposed method is demonstrated by numerical evaluations and real-world experiments, showing its capability of material classification, even for visually indistinguishable objects.

Introduction Duodenal gastrointestinal stromal tumours (GIST) are rare. Therefore, difficulties are experienced when selecting the appropriate surgical procedure in patients with duodenal GISTs. This report presents the cases of three patients with duodenal GISTs who underwent wedge resection. This report would help surgeons identify clinical features and surgical procedures in patients with duodenal GISTs. Presentation of case Three patients were diagnosed with duodenal submucosal tumours. The first patient presented with melena, the second with postoperative anaemia, and the third with an incidental finding of a large abdominal tumour after presenting with ischaemic colitis. All tumours arose in the 2nd portion of the duodenum and measured 3.5, 3, and 9.2 cm, respectively. Wedge resection of the duodenum was performed in all patients. In patients one and two, simple closure of duodenal wall was performed after wedge resection. In patient three, side-to-side anastomosis with the jejunum was performed because a large area of the wall was removed using the wedge resection technique. Pancreatoduodenectomy was avoided in all patients. Recurrence was not noted in any patient. Discussion Since GISTs are not generally associated with lymph node metastasis, local resection with negative margins is sufficient to surgically manage patients with GISTs. Conclusion Our results indicated the effectiveness of performing wedge resection for duodenal GISTs not in close proximity to the ampulla of Vater. Moreover, less invasive procedures should be adopted in patients with duodenal GISTs., Highlights • GIST are derived from the intestinal cells of Cajal in the GIT and mesentery. • The occurrence of duodenal GIST is rare. • Complete wedge resection was performed for GIST at the 2nd portion of the duodenum. • Wedge resection is a feasible and safe surgical method for duodenal GISTs.

This paper presents an industry-ready descattering method that is easily applied to a food production line. The system consists of multiple sets comprising a linear image sensor and linear light source, which are slanted at different angles. The images captured by these sensors, which are partially clear along the perpendicular direction to the sensor, are computationally integrated into a single clear image over the frequency domain. We assess the effectiveness of the proposed method by simulation and by our prototype system, which demonstrates the feasibility of the proposed method on an actual production line.

The double exponential formula, or DE formula, is a high-precision integration formula using a change of variables called a DE transformation; it has the disadvantage that it is sensitive to singularities of an integrand near the real axis. To overcome this disadvantage, Slevinsky & Olver (2015, On the use of conformal maps for the acceleration of convergence of the trapezoidal rule and Sinc numerical methods. SIAM J. Sci. Comput., 37, A676–A700) attempted to improve the formula by constructing conformal maps based on the locations of singularities. Based on their ideas, we construct a new transformation formula. Our method employs special types of the Schwarz–Christoffel transformation for which we can derive the explicit form. The new transformation formula can be regarded as a generalization of DE transformations. We confirm its effectiveness by numerical experiments.

In this paper, we present a practical method for reconstructing the bidirectional reflectance distribution function (BRDF) from multiple images of a real object composed of a homogeneous material. The key idea is that the BRDF can be sampled after geometry estimation using multi-view stereo (MVS) techniques. Our contribution is selection of reliable samples of lighting, surface normal, and viewing directions for robustness against estimation errors of MVS. Our method is quantitatively evaluated using synthesized images and its effectiveness is shown via real-world experiments.