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Background: Pulmonary hypertension (PH) secondary to respiratory disease is caused by pulmonary vascular remodeling and hypoxia. Severe PH can induce various clinical signs, including syncope and right‐sided heart failure. Hypothesis/Objectives: To investigate the echocardiographic characteristics in dogs with PH secondary to respiratory diseases. Animals: Thirty‐one dogs with respiratory diseases with or without PH and 15 healthy dogs. Methods: Prospective cross‐sectional study. Dogs were classified according to respiratory disease (obstructive airway/lung disease [OALD] or restrictive lung disease [RLD]) and PH‐relevant signs. The association between echocardiographic variables and PH (classified by respiratory disease and PH‐relevant signs) was investigated. Results: Twenty‐one dogs were diagnosed with PH; of these, 11 showed PH‐related signs (OALD, n = 2; RLD, n = 9), 14 had right ventricular hypertrophy, and 19 had pulmonary arterial enlargement. Right ventricular dysfunction and dilatation were observed only in dogs with PH‐related signs (n = 10). Left and right ventricular stroke volumes were significantly lower in dogs with PH (median [interquartile range]: 17.2 [12.4‐20.8] and 16.8 [15.3‐29.5] mL/m2, respectively). Dogs with RLD had higher echocardiography‐estimated pulmonary vascular resistance than those with OALD (median [interquartile range]: 3.1 [1.9‐3.3] and 1.6 [1.3‐2.2], respectively). Conclusions and Clinical Importance: Pulmonary arterial enlargement was the most common echocardiographic finding in dogs with PH secondary to respiratory diseases. Right ventricular dysfunction, dilatation, and decreased left and right ventricular stroke volume were significantly associated with the PH‐related signs, indicating that comprehensive echocardiography is recommended in dogs with respiratory disease. Restricted lung disease might induce more severe PH than OALD. [ABSTRACT FROM AUTHOR]

Background: Progression to combined post‐ and pre‐capillary pulmonary hypertension (PH) provides prognostic information in human patients with post‐capillary PH. Pulmonary vascular resistance estimated by echocardiography (PVRecho) is useful for the stratification of dogs with myxomatous mitral valve disease (MMVD) and detectable tricuspid regurgitation. Objectives: To evaluate the prognostic value of PVRecho in dogs with MMVD. Animals: Fifty‐four dogs with MMVD and detectable tricuspid regurgitation. Methods: Prospective cohort study. All dogs underwent echocardiography. The PVRecho was calculated based on tricuspid regurgitation and the velocity‐time integral of the pulmonary artery flow. To evaluate the influence of echocardiographic variables on cardiac‐related deaths, Cox proportional hazard analysis was performed. Additionally, Kaplan‐Meier curves classified by PVRecho tertiles were made and compared using log‐rank tests to evaluate the influence of PVRecho on all‐cause mortality and cardiac‐related death. Results: The median follow‐up time was 579 days. Forty‐one dogs with MMVD (PH severity [number]: no or mild, 21/33; moderate, 11/11; severe, 9/10) died during the study. In the multivariable Cox proportional hazard analysis adjusted for age, sildenafil administration, and American College of Veterinary Internal Medicine stage of MMVD, left atrial to aortic diameter ratio and PVRecho remained significant (adjusted hazard ratio [95% confidence interval]: 1.2 [1.1‐1.3] and 2.1 [1.6‐3.0], respectively). Higher PVRecho showed a significant association with lower survival rates. Conclusions and Clinical Importance: Left atrial enlargement and high PVRecho were independent prognostic factors in dogs with MMVD and detectable tricuspid regurgitation. [ABSTRACT FROM AUTHOR]

Introduction: The laparoscopic approach for elective femoral herniorrhaphy is well established. However, femoral hernias often present as incarcerations and require emergency repair surgery, mainly using the open approach. This study aimed to retrospectively analyze the efficacy of the laparoscopic approach for incarcerated femoral hernias. Methods: Data of patients who underwent emergency surgery for incarcerated femoral hernia between April 2016 and August 2021 were retrospectively analyzed. Laparoscopy was performed whenever possible; however, conversion to an open approach remained a fallback option for when laparoscopic repair was not possible. In laparoscopic repair, incarcerated femoral hernias reduced using traction, water pressure, and preperitoneal methods. Data of patients who underwent open repair and laparoscopy were then compared. Results: During the observation period, 20 patients underwent emergency surgery for incarcerated femoral hernia. Eleven patients subsequently underwent repair using a laparoscopic approach, and eight underwent repair using an open approach. Only one patient underwent intestinal resection without hernia repair due to perforated bowel. Operative time for laparoscopic repair was longer. Mesh repair was performed in 18 patients. Four patients each in the laparoscopic repair and open group required intestinal resection. Conclusion: Incarcerated femoral hernias can be safely repaired using the laparoscopic approach. [ABSTRACT FROM AUTHOR]

Fundamental studies were conducted to develop a facility having an adequate air circulation system for growing healthy plants over a long term under microgravity conditions in space. To clarify the effects of gravity on heat and gas exchanges between plant leaves and the ambient air, surface temperatures and net photosynthetic rates of barley leaves were evaluated at gravity levels of 0.01, 1.0, and 2.0 g for 20 sec each during parabolic airplane flights. Thermal images were captured using infrared thermography at an air temperature of 22°C, a relative humidity of 18%, and an irradiance of 260 W/m2. The net photosynthetic rates were determined by means of a chamber method with an infrared gas analyzer at an air temperature of 20°C, a relative humidity of 50%, and photosynthetic photon fluxes (PPFDs) of 250 and 500 μmol/m2/sec. Mean leaf temperatures increased by 1.9°C with decreasing gravity levels from 1.0 to 0.01 g and decreased by 0.6°C with increasing gravity levels from 1.0 to 2.0 g. The increase in leaf temperatures was greater at the regions closer to the leaf tip and at most 2.5°C over 20 sec as gravity decreased from 1.0 to 0.01 g. The net photosynthetic rate decreased by 20% with decreasing gravity levels from 1.0 to 0.01 g and increased by 10% with increasing gravity levels from 1.0 to 2.0 g at a PPFD of 500 μmol/m2/sec. The heat and gas exchanges between leaves and the ambient air were suppressed more at the lower gravity levels. The retardation would be caused by heat and gas transfers with less heat convection. Restricted free air convection under microgravity conditions in space would limit plant growth by retarding heat and gas exchanges between leaves and the ambient air. [ABSTRACT FROM AUTHOR]

The authors describe a technique for selectively sharpening only edges that were blurred due to various causes without making interference factors such as random noise more conspicuous. The selective sharpening technique described in this paper is implemented as an iterative updating nonlinear algorithm obtained by discretizing a type of nonlinear reaction-diffusion time-evolution equations. The update terms of this algorithm consist of a quadratic nonlinear smoothing term, reaction term, and overshooting term. By performing quantitative evaluation experiments, the authors showed that the proposed technique has significantly better selective sharpness enhancement capabilities than existing sharpness enhancement techniques such as the peaking method. In addition, the authors introduced a processing parameter adaptive control method in the proposed technique and applied it to the suppression of breathing distortions in video sequences. Breathing distortions, which are video sequence distortions that often appear in old films, are time-varying blurring distortions that occur due to temporal variations of the focus. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(5): 33–47, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.10086 [ABSTRACT FROM AUTHOR]

In this paper we describe a method for modeling and rendering dynamic behavior of fluids withsplashes and foam. A particle system is built into a fluid simulation system to represent an ocean wavecresting and spraying over another object. We use the Cubic Interpolated Propagation (CIP) method asthe fluid solver. The CIP method can solve liquid and gas together in the framework of fluid dynamicsand has high accuracy in the case of relatively coarse grids. This enables us to simulate the fluids in ashort time and describe the motion of splashes in the air that is associated with the liquid motion well.The foam floating on the water also can be described using the particle system. We integrate the rigidbody simulation with the fluid and particle system to create sophisticated scenes including splashes andfoam. We construct state change rules that are used with the particle system. This controls the generation,vanishing and transition rule of splashes and foam. The transition rule makes the seamless connection betweena splash and foam. We employed a fast volume rendering method with scattering effect for particles.One of the important features of our method is the combination of fast simulation and rendering techniques,which provides dynamic and realistic scenes in a short time. [ABSTRACT FROM AUTHOR]

The problem in which an image containing moving objects is to be segmented into multiple subimages, each of which follows a single set of motion parameters, is called the global motion segmentation problem. The segmentation and the estimation of the motion parameters are mutually dependent, and consequently, it is difficult to solve independently the segmentation problem and the estimation problem for the motion parameters. This paper proposes a new algorithm for global motion segmentation. The proposed method directly processes the input image sequence, and the segmentation and the motion parameters are simultaneously estimated. This paper presents the detailed procedure for the computation and the application of the proposed method to the conversion from interlaced scanning to progressive scanning. © 2000 Scripta Technica, Syst Comp Jpn, 31(11): 92–100, 2000 [ABSTRACT FROM AUTHOR]

The wavelet transform is a practical method for multiresolution analysis. Previously, methods for describing the transformed signal using zero-crossing information and additional complementing information (zero-crossing representation) have been studied. The zero-crossing representation, however, presents problems in that the physical interpretation of the applied additional information is not clear, and reconstruction of the original signal from the zero-crossing representation involves iterations of nonlinear operations. Other problems include the fact that extension to the multidimensional case is difficult and that the computational complexity is considerable. In this paper, the authors propose a new zero-crossing representation that uses the additional information with clear physical interpretation and has a form that is easy to handle in signal processing. A method is proposed to reconstruct the original signal from the zero-crossing representation. The method uses iterative linear operations with a theoretical guarantee of convergence and has lower computional complexity than the conventional method. The proposed zero-crossing representation is extended to the two-dimensional case and is applied to an actual image. It is experimentally verified that the reconstructed image is a good approximation to the original signal. Furthermore, the amount of additional information in the zero-crossing representation is reduced. The quality degradation of the reconstructed image is examined. © 1998 Scripta Technica, Electron Comm Jpn Pt 3, 82(1): 68–78, 1999 [ABSTRACT FROM AUTHOR]

The “layered representation” is a method to represent a moving image by relatively moving layered maps in each divided region after they have been superimposed in image depth order, like cell images in an animated picture. The conventional layered-representation coding method can efficiently represent an object with small movements, such as a background, but the method has difficulty in representing a nonrigid object which changes its texture and shape, like an image of a person. This paper describes a layered-representation coding method which overcomes this difficulty. The proposed method divides each region along the time axis, and a moving image including nonrigid objects is efficiently reconstructed by mixing maps of frames. This paper also describes an expanded setting representation which can treat three-dimensional data efficiently. The proposed method can represent a smooth moving image without discontinuous frame shifting, since its image quality can be controlled spatially and temporally. The proposed method is compared with a conventional method (waveform-similarity method H.263) of a low-bit rate (less than 32 kbit/s), the former being superior to the latter in a visual evaluation. © 1999 Scripta Technica, Syst Comp Jpn, 30(1): 70–80, 1999 [ABSTRACT FROM AUTHOR]

This paper presents an optimal design method of a multiple-valued current-mode (MVCM) integrated circuit based on dual-rail source-coupled logic, in which both power dissipation and switching delay are minimized simultaneously. The minimum delay of the MVCM circuit is determined by the optimal gate-width ratio of MOS transistors in a current mirror and a threshold detector, which are connected serially. The gate width of all of the threshold detectors is minimized while keeping the above gate-width ratio, which minimizes power dissipation. As a typical example of the MVCM logic circuit, the performance of an optimized 54 × 54-bit multiplier is estimated to be about 1.7 times faster than that of a corresponding binary device under a standard 0.5-μm CMOS process technology with a supply voltage of 1.5 V. © 1998 Scripta Technica, Syst Comp Jpn, 29(11): 40–47, 1998 [ABSTRACT FROM AUTHOR]

For high-efficiency image compression, previously, an SVD (singular value decomposition)-based coder was developed using vector quantization, called SVD-VQ. This paper proposes an improved quantization SVD-VQ scheme. For every input subblock, the SVD- VQ coder scalar-quantizes a singular value and vector-quantizes two singular vectors, separately. The SVD-VQ decoder reproduces a subblock as the product of these quantization outputs, but does not necessarily produce a reconstruction with the minimum distortion in an image space. This paper develops a quantization scheme where the minimum-distortion reconstruction is always provided in the original image space and presents its design algorithm. The improved SVD-VQ shows A/N performance improvement of 0.5 - 1.0 dB over the conventional SVD-VQ, and is similar in performance to the adaptive DCT (discrete cosine transform) coder. [ABSTRACT FROM AUTHOR]

The authors have previously proposed a quantization scheme in which the ac discrete cosine transform coefficients after normalization are quantized by the gain/shape vector quantizer (called DCT-G/SVQ). It is shown from the relation between the quantization complexity and the S/N ratio that DCT-G/SVQ exhibits a better performance than the discrete cosine transform coding with vector quantization (called DCT-VQ) discussed in the literature [6]. This paper proposes the adaptive DCT-G/SVQ, in which the adaptive control is introduced £or the coding parameters of DCT-G/SVQ. Two methods of adaptive control are considered--the mode- selection and the recursive adaptation. The adaptive DCT-G/SVQ has a better performance than the traditional adaptive discrete cosine transform coding using the scalar quantizer. In other words, the S/N ratio is improved by 1.0 to 1.5 dB in the mode-selection adaptive control coding at the same coding rate. The S/N ratio in the recursive adaptive control coding is improved by 0.5 to 1.0 dB. The adaptive DCT-G/SVQ based on the mode-selection control exhibits nearly the same coding performance as the adaptive DCT-VQ of [9] with the same adaptive control scheme, but is superior since it requires less complexity in quantization. [ABSTRACT FROM AUTHOR]

A gain/shape vector quantizer for orthogonal transform domain has been designed based on a previous paper [11] on a gain/shape vector quantizer for a spherically symmetric random source. Such a design method is used in the design of a discrete cosine transform encoder with gain/shape vector quantizer. This encoder is similar to that described in [7] except in the following: (i) it has a gain/shape codebook; and (ii) its normalized coefficients of discrete cosine transform are modeled as having spherically symmetric distribution. The S/N rendition of this encoder is 1.0 - 2.5 dB better than that of the DCT coding scheme with Max-type scalar quantizer at the same bit rate. Furthermore, in spite of its similarity to the conventional discrete cosine transform coding scheme with vector quantizer [7], the encoder introduced in this paper delivers higher S/N using the same number of multiplications for the quantization of normalized coefficients, and/or the same amount of memory for the codebook. [ABSTRACT FROM AUTHOR]

The multiscale wavelet transform (MWT) is the method of multiple resolution analysis using the wavelet transform. In MWT with the property of the second-order derivative, the position of the zero-crossing point of the transform signal corresponds to the position of the edge of the original signal. The edge has an important role in image information. If the correspondence of the zero-crossing points related to the edges can be established between scanning lines or between frames by some means, the correspondence can be utilized in the sophistication of image processing (such as motion analysis, stereo matching, interpolation, and noise reduction). From such a viewpoint, this paper discusses the correspondence between the zero-crossing points in MWT, i.e., the correspondence of scales and the correspondence between two similar signals, and presents a method that provides visually plausible correspondence as a result. Especially for the correspondence between signals, the accuracy of the correspondence of zero-crossing points is improved by introducing the cost function. Computational complexity is kept within a practical range, by applying the dynamic programming and utilizing the branch structure of the zero-crossing points among various scales. The idea of cross-validation is applied to the correspondence of signals between the scanning lines of the image, and a method is composed that evaluates visually the quality of the signal correspondence method by the naked-eye observation of this image. With this evaluation method, the usefulness of the proposed algorithm for the signal correspondence and its problems are indicated. It is shown that a visually reasonable result is obtained by adjusting the weight coefficient of the multiplication factor of the cost function in the signal correspondence process. [ABSTRACT FROM AUTHOR]

A novel nonlinear noise reduction method that effectively reduces both impulsive and Gaussian noise is proposed and investigated. In the proposed method, a zero-crossing representation that is a kind of compressed description of the coefficients of a multiscale wavelet transform is obtained first and then, using characteristics of the transform coefficients, any noise that is thought to have entered the zero-crossing representation suppressed. Noise reduction is achieved by reconstructing the image from the modified zero-crossing representation. It is shown that, compared to nonlinear filtering methods, the proposed method is more effective for simultaneously reducing both impulsive and Gaussian noise for one-dimensional signals and two-dimensional image signals. [ABSTRACT FROM AUTHOR]

This paper discusses a reconstruction method of the image signal from the zero-crossing representation. First, the one- and two-dimensional multiscale wavelet transforms are described which have the completeness and the translation invariance. A new zero-crossing representation is proposed in which the zero-crossing points are extracted from the multiscale wavelet transform. The information concerning the maximum value (the minimum value when negative) between two consecutive zero-crossing points as well as its position is combined. Then it is shown that the original signal can be reconstructed with a stable and fast convergence from the zero-crossing representation of the signal through the iterated projections to the convex set. The effect of the wavelet basis filter on the convergence in the reconstruction is investigated, and a necessary condition for the optimal basis filter is derived considering the convergence. Finally, a new basis filter is designed using the B-spline function and the usefulness of the proposed method is demonstrated for the one-dimensional signal and the image signal. It is shown also that the signal reconstruction procedure converges with stability, even if there exists an error at the extracted zero-crossing point. [ABSTRACT FROM AUTHOR]

This paper proposes a new coding method using structural features such as shape and motion in a moving image so that they are described as plane motion in a 3D space. In this method, a layered representation (a moving image is described on a 2D projection plane) is extended by using a setting representation so as to handle 3D data. In the setting representation, 3D parameters which describe the orientation of a plane and the motion of a rigid body are needed for the regions that move coherently on the projection plane. Parameters can be estimated stably by applying a conventional 3D parameter estimation algorithm (which uses the square-error criterion based on the assumption of equal intensity between adjacent frames) to multiple frames. This paper also proposes a method of integration of the rigid-body motion of multiple regions so that the motion of images can be described more efficiently. The proposed method is compared with the layered representation using 2D data, and a conventional waveform-based method. The results show the effectiveness of the proposed method. © 1998 Scripta Technica, Syst Comp Jpn, 28(10): 50–59, 1997 [ABSTRACT FROM AUTHOR]

To improve the signal-to-noise (S/N) ratio of Raman spectra, we developed a sample flow system in a vertical flow apparatus (VFA). The VFA consists of a brass plate with a drilled pinhole, cover slip on the brass plate, circulation pump, and reservoir. The sample solution flows through a gap between the brass plate and cover slip, spouts from the pinhole, and forms a laminar flow column. The sample column and surrounding air, respectively, serve as the core and cladding of an optical fiber that confines both excitation beam and scattered light owing to the total reflection at the core-cladding interface. The VFA enabled the enhancement and efficient collection of the Raman signal. The VFA with a 0.2-mm pinhole produced a 12.0-fold enhancement of the non-resonant Raman signal of H2O compared to that measured using a capillary, and the S/N ratio exhibited a 4.1-fold enhancement. The signal count was inversely proportional to the square of the pinhole diameter ( φ), possibly owing to the dependence on the density of the electromagnetic energy of the excitation beam in the sample column. The S/N ratio was inversely proportional to φ because the signal enhancement was accompanied by an increase in the photon shot noise. The VFA also produced a 4.9-fold enhancement of the resonance Raman signal of Congo red, although the enhancement factor was smaller than that in the non-resonant Raman measurement. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Idiopathic basal ganglia calcification (IBGC) is a neuropathological condition known to manifest as motor disturbance, cognitive impairment, and psychiatric symptoms. The pathophysiology of the psychiatric symptoms of IBGC, however, remains controversial. A previous biochemical study suggested that dopaminergic impairment is involved in IBGC. We thus hypothesized that dopaminergic dysfunction might be related with the psychiatric manifestations of IBGC. We used positron emission tomography to measure glucose metabolism and dopaminergic function in the basal ganglia of an IBGC patient with psychiatric symptoms. The results showed that widespread hypometabolism was evident in the frontal, temporal, and parietal cortices while the decline in dopaminergic function was severe in the bilateral striatum. The functional decline of the dopamine system in the calcified area of the bilateral striatum and the disruption of cortico-subcortical circuits may contribute to clinical manifestations of IBGC in our patient. [ABSTRACT FROM AUTHOR]

An 8‐year‐old Leonberger receiving immunosuppressive treatment with clinical signs of acute dyspnea, cyanosis, and difficulty standing was referred to our institution (Day 1). Treatment including oxygen, clopidogrel, and low‐molecular‐weight heparin was initiated for suspected pulmonary thrombosis. However, exertional dyspnea persisted until Day 10, and increased tricuspid regurgitation velocity, pulmonary vascular resistance, and McConnell's signs also were observed. Thus, beraprost sodium was administered PO on Day 11 to treat suspected pulmonary hypertension. On Day 13, contrast‐enhanced computed tomography identified extensive contrast defects in the pulmonary arteries, and IV monteplase was administered on Days 14 and 18, with marked improvement in respiratory status and exertional dyspnea on Day 20. Right ventricular function and McConnell signs also improved, and tricuspid regurgitation velocity and pulmonary vascular resistance decreased. On Day 250, echocardiography indicated further improvement in pulmonary hypertension pathophysiology. The patient was still progressing well with antithrombotic and pulmonary vasodilator treatment 400 days later. [ABSTRACT FROM AUTHOR]

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