Atsushi Nakazawa

[64] Pyrocatechase (pseudomonas)☆

Publisher Summary This chapter describes the assay, purification, and properties of pyrocatechase. The assay is based on the measurement spectrophotometrically of the rate of formation of cis,cis-muconic acid. The rate of oxygen uptake can be measured by means of a polarographic technique. One unit of enzyme activity is defined as that amount that catalyzes the formation of 1 micromole of cis,cis-muconic acid per minute at 24°. Protein is determined spectrophotometrically from the absorbance at 280 and 260 mμ. The crude enzyme is stable for long periods of time at 4°. The purified enzyme is less stable; it loses about 15% of its activity during storage for four days at 4 °. The enzyme is most stable at a pH range of 8.0–9.5. Upon freezing, the purified enzyme at -20o for several months, the red enzyme solution changes to a more bluish color with a concomitant complete loss of activity. Sodium dithionite, ascorbic acid, sodium borohydride, mercaptoethanol, cysteine, reduced glutathione, or ferrous ion increase the rate of inactivation.

Task model of lower body motion for a biped humanoid robot to imitate human dances

The goal of this study is developing a biped humanoid robot that can observe a human dance performance and imitate it. To achieve this goal, we propose a task model of lower body motion, which consists of task primitives (what to do) and skill parameters (how to do it). Based on this model, a sequence of task primitives and their skill parameters are detected from human motion, and robot motion is regenerated from the detected result under constraints of a robot. This model can generate human-like lower body motion including various waist motions as well as various stepping motions of the legs. Generated motions can be performed stably on an actual robot supported by its own legs. We used improved robot hardware HRP-2, which has superior features in body weight, actuators, and DOF of the waist. By using the proposed method and HRP-2, we have realized a dance performance of Japanese folk dance by the robot, which is synchronized with a performance of a human grand master on the same stage.

Comparison of outer membrane protein genes omp and pmp in the whole genome sequences of Chlamydia pneumoniae isolates from Japan and the United States.

Chlamydia pneumoniae is a widespread pathogen of the respiratory tract that is also associated with atherosclerosis. The whole genome sequence was determined for a Japanese isolate, C. pneumoniae strain J138. The sequence predicted a variety of genes encoding outer membrane proteins (OMPs) including ompA and porB, another 10 predicted omp genes, and 27 pmp genes. All were detected in the whole genome sequence of strain CWL029, a strain isolated and sequenced in the United States. A comparative study of the OMPs of the two strains revealed a nucleotide sequence identity of 89.6%-100% (deduced amino acid sequence identity, 71.1%-100%). The overall genomic organization and location of genes are identical in both strains. Thus, a few unique sequences of the OMPs may be essential for specific attributes that define the differential biology of two C. pneumoniae strains.

Real-Time Space Carving Using Graphics Hardware

Reconstruction of real-world scenes from a set of multiple images is a topic in computer vision and 3D computer graphics with many interesting applications. Attempts have been made to real-time reconstruction on PC cluster systems. While these provide enough performance, they are expensive and less flexible. Approaches that use a GPU hardware-acceleration on single workstations achieve real-time framerates for novel-view synthesis, but do not provide an explicit volumetric representation. This work shows our efforts in developing a GPU hardware-accelerated framework for providing a photo-consistent reconstruction of a dynamic 3D scene. High performance is achieved by employing a shape from silhouette technique in advance. Since the entire processing is done on a single PC, the framework can be applied in mobile environments, enabling a wide range of further applications. We explain our approach using programmable vertex and fragment processors and compare it to highly optimized CPU implementations. We show that the new approach can outperform the latter by more than one magnitude and give an outlook for interesting future enhancements.

Non-calibrated and real-time human view estimation using a mobile corneal imaging camera

We present a mobile human view estimation system using a corneal imaging technique. Compared to the current eye gaze tracking (EGT) systems, our system does not require per-session calibrations and a frontal view (scene) camera, making it suitable for wearable glass systems because it is easier to use and more socially acceptable due to the lack of a frontal scene camera. Our glasses system consists of a glass frame and a micro eye camera that captures the eye (corneal) reflections of a user. 3D corneal pose tracking is performed for the captured images by using a particle filter-based real-time tracking method leveraged by a 3D eye model and weak perspective projection. We then compute the gaze reflection point (GRP) where the light from the point of gaze (PoG) is reflected, enabling us to identify where a user is looking in a scene image reflected on the corneal surface. We conducted experiments using a standard computer display setup and several real-world scenes, and found that the proposed method performs with considerable accuracy under non-calibrated setups. This demonstrates its potential for various purposes such as the user interface of a glasses systems and the analysis of human perceptions in actual scenes for marketing, environmental design, and quality-of-life applications.

I See What You See: Point of Gaze Estimation from Corneal Images

Eye-gaze tracking (EGT) is an important problem with a long history and various applications. However, state-of-the-art geometric vision-based techniques still suffer from major limitations, especially (1) the requirement for calibration of a static relationship between eye camera and scene, and (2) a parallax error that occurs when the depth of the scene varies. This paper introduces a novel concept for EGT that overcomes these limitations using corneal imaging. Based on the observation that the cornea reflects the surrounding scene over a wide field of view, it is shown how to extract that information and determine the point of gaze (PoG) directly in an eye image. To realize this, a closed-form solution is developed to obtain the gaze-reflection point (GRP), where light from the PoG reflects at the corneal surface into a camera. This includes compensation for the individual offset between optical and visual axis. Quantitative and qualitative evaluation shows that the strategy achieves considerable accuracy and successfully supports depth-varying environments. The novel approach provides important practical advantages, including reduced intrusiveness and complexity, and support for flexible dynamic setups, non-planar scenes and outdoor application.

Purification and properties of pyrocatechase from Pseudomonas fluorescens

1. n1.|In order to investigate physicochemical and chemical properties of pyrocatechase (catechol:oxygen 1,2-oxidoreductase, EC 1.13.1.1), a new method for the large-scale preparation of the enzyme from Pseudomonas fluorescens (ATCC 11250) was developed. The purified enzyme had a specific activity of 28 μmoles/min per mg of protein at 24°, and was homogeneous as judged by ultracentrifugation and electrophoresis. n n2. n2.|The molecular weight was found to be approx. 100000 by the Archibald method, sedimentation-diffusion measurements, determination of the iron content, and amino acid analyses. The enzyme was shown to be an acidic protein by free-boundary electrophoresis. A solution of the purified enzyme had a distinct absorption at 279 mμ with a shoulder at 322 mμ and a broad absorption between 400 to 600 mμ. The visible region of absorption spectrum changed with varying pH values. n n3. n3.|On the basis of a molecular weight of 100000, the enzyme appeared to contain 3 or 4 half-cystines including at least 1 free sulfhydryl group and 2 atoms of inorganic iron per molecule. The amino acid composition of the enzyme was also presented.

Super-Resolution from Corneal Images.

The cornea of the human eye reflects the light from a person’s environment. Modeling corneal reflections from an image of the eye enables a number of applications, including the computation of scene panorama and 3D model, together with the person’s field of view and point of gaze [4]. The obtained environment map enables general applications in vision and graphics, such as face reconstruction, relighting [3] and recognition [5]. In reality, however, even if we use a carefully-adjusted high-resolution camera in front of the eye, the quality of corneal reflections is limited due to low resolution and contrast, iris texture and geometric distortion. This paper introduces an approach to overcome these issues through a super-resolution (SR) [6] strategy for corneal imaging that reconstructs a high-resolution (HR) scene image from a series of lower resolution (LR) corneal images such as occurring in surveillance or personal videos. The process comprises (1) single image environment map recovery, (2) multiple image registration, and (3) HR image reconstruction. This is also the first non-central catadioptric approach for multiple image SR. Corneal reflection modeling. We apply a common geometric eye model, where eyeball and cornea (Figure 1 (a)) are approximated as two overlapping spherical surfaces. A simple strategy assuming weak perspective projection recovers the pose of the model by reconstructing the pose of the circular iris from its elliptical projected contour (Figure 1 (b)). A corneal image is transformed into a spherical environment map by calculating the intersection and reflection at the corneal surface. Since the eye model only approximates the true corneal geometry, it is not possible to obtain an accurate registration for the whole environment map. Instead, we assume spherical curvature for a user-defined region of interest, where we project the environment map to a local tangent plane (Figure 1 (c)). Registration further requires the forward projection from the tangent plane into the image. As common iterative methods are not feasible to handle the large number of re-projections, we apply a recent analytic method that requires solving a 4th-order polynomial equation (for the case of a spherical mirror), that is calculated in closed form [1].

Circular dichroism of biodegradative threonine deaminase

Abstract Biodegradative threonine deaminase of Escherichia coli ( Umbarger and Brown, 1957 ) contains pyridoxal phosphate (PLP) as a cofactor and is activated by AMP ( Wood and Gunsalus, 1949 ; Phillips and Wood, 1964 ; Hirata et al . , 1965 ). In addition to the catalytic function through Schiff base formation with substrate, the enzymebound PLP was shown to contribute to the stabilization of the enzyme conformation ( Tokushige, 1967 ). In this paper is described the circular dichroism (CD) of PLP in the biodegradative threonine deaminase in relation to the catalytic reaction; the results are pertinent to the mode of binding of PLP to the enzyme protein, and their interaction.

Synthetic Evidential Study as Primordial Soup of Conversation

Synthetic evidential study (SES for short) is a novel technology-enhanced methodology for combining theatrical role play and group discussion to help people spin stories by bringing together partial thoughts and evidences. SES not only serves as a methodology for authoring stories and games but also exploits the framework of game framework to help people sustain in-depth learning. In this paper, we present the conceptual framework of SES, a computational platform that supports the SES workshops, and advanced technologies for increasing the utility of SES. The SES is currently under development. We discuss conceptual issues and technical details to delineate how much we can implement the idea with our technology and how much challenges are left for the future work.