bluuebunny/crossref_metadata_2025 huggingface dataset:
Cisplatin induces mitochondrial oxidative stress with resultant energetic metabolism impairment, membrane rigidification and apoptosis in rat liver
Authors: Martins N. M. , Santos N. A. G. , Curti C. , Bianchi M. L. P. , Santos A. C.
Published: June 2007

Cisplatin is a potent and widely used chemotherapeutic agent. Nephrotoxicity induced by this drug has been well documented. However, very little information is available on cisplatin‐induced hepatotoxicity and its underlying mechanism remains unclear. High doses of cisplatin have been known to produce hepatotoxicity. Additionally, elevated expression of CYP 2E1 has been associated with enhanced cisplatin‐induced hepatotoxicity. Several studies suggest that cisplatin toxicity occurs by the increased generation of reactive oxygen species (ROS) in mitochondria. Therefore, the present study examined, in vivo, the cisplatin‐induced effects on hepatic mitochondrial structure and function as well as the occurrence of hepatocellular death by apoptosis. Adult male Wistar rats (200–220 g) were divided into two groups (n = 8) treated as follows: (1) control group (saline solution, 1 ml 100 g−1 body weight, i.p.) and (2) cisplatin group (10 mg kg−1 body weight, i.p.). The animals were killed 72 h after the treatment. Hepatotoxicity was evidenced in the cisplatin group by the increased serum levels of alanine (ALT) and aspartate (AST) aminotransferases. The mechanism of cisplatin‐induced hepatotoxicity was found to involve membrane rigidification; decreased GSH/GSSG ratio, ATP, GSH and NADPH levels; lipid peroxidation; oxidative damage of cardiolipin and protein sulfhydryl groups. Moreover, cell death by apoptosis was also demonstrated and the findings strongly suggest the participation of the mitochondrial signaling pathway in this process. Therefore, the results show the key role of mitochondria in the hepatotoxicity induced by cisplatin and delineate several mitochondrial processes that could be targeted in future cytoprotective therapy approaches. Copyright © 2007 John Wiley & Sons, Ltd.
Variation of spectral, structural, and vibrational properties within the intrinsically fluorescent proteins family: A density functional study
Authors: Nifosí Riccardo , Amat Pietro , Tozzini Valentina
Published: June 2007

We report an extensive (time‐dependent) density functional study of the whole series of the chromophores within the Intrinsically Fluorescent Protein family, in the relevant conformations and protonation states. Over 30 structures are considered, including three newly discovered chromophores (zFP, Kaede, and the Orange variant of DsRed). Ab initio calculations on selected structures are also performed in order to assess the performances of TDDFT along the family. The use of a uniform scheme for all structures allows to establish relationships between the absorption energy and electrostatic, structural or vibrational properties of the chromophores. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007
Pushing the envelope on youth civic engagement: A developmental and liberation psychology perspective
Authors: Watts Roderick J. , Flanagan Constance
Published: June 2007

In this article, we take a critical look at the growing interest in U.S. political participation as it exists in the youth civic engagement literature. Our critique draws from principles of liberation and developmental psychology, and from the incisive writings of experts in youth organizing. Youth Organizing evolved from the Positive Youth Development (PYD) and Community Youth Development (CYD) perspectives but its addition of social justice activism is consistent with liberation psychology. The essence of our critique is this: Although there is certainly value in the current civic engagement literature, much of it focuses on the maintenance of social and political institutions rather than on action for social justice. To promote a better balance, and one more relevant to the lives of youth of color and other marginalized young people, we offer a framework for empirical research on youth sociopolitical development. The focus is on the relationship between social analysis (including critical consciousness) and societal involvement that includes the full range of service and political work. Because youth is the focus, we also include a brief discussion of a distinctive challenge that adults face in doing just work with young people—namely, adultism. © 2007 Wiley Periodicals, Inc. J Comm Psychol 35: 779–792, 2007.
Perturbation of mouse glioma MRS pattern by induced acute hyperglycemia
Authors: Simões R. V. , García‐Martín M. L. , Cerdán S. , Arús C.
Published: June 2007

1H MRS is evolving into an invaluable tool for brain tumor classification in humans based on pattern recognition analysis, but there is still room for improvement. Here we propose a new approach: to challenge tumor metabolism in vivo by a defined perturbation, and study the induced changes in MRS pattern. For this we recorded single voxel 1H MR spectra from mice bearing a stereotactically induced GL261 grade IV brain glioma during a period of induced acute hyperglycemia. A total of 29 C57BL/6 mice were used. Single voxel spectra were acquired at 7 T with point resolved spectroscopy and TE of 12, 30 and 136 ms. Tumors were induced by stereotactic injection of 105 GL261cells in 17 mice. Hyperglycemia (up to 338 ± 36 mg/dL glucose in the blood) was induced by intraperitoneal bolus injection. Maximal increases in glucose resonances of up to 2.4‐fold were recorded from tumors in vivo. Our observations are in agreement with extracellular accumulation of glucose, which may suggest that glucose transport and/or metabolism are working close to their maximum capacity in GL261 tumors. The significant and specific MRS pattern changes observed when comparing euglycemia and hyperglycemia may be of use for future pattern‐recognition studies of animal and human brain tumors by enhancing MRS‐based discrimination between tumor types and grades. Copyright © 2007 John Wiley & Sons, Ltd.
The gel swelling properties of alginate fibers and their applications in wound management
Authors: Qin Yimin
Published: June 2007

Calcium alginate fibers have a novel gel‐forming capability in that, upon the ion exchange between sodium ions in the contact solution and calcium ions in the fiber, the fiber slowly transforms into a fibrous gel. This paper reviews the principles of the gel‐forming process for alginate fibers and analyzed the gelling behavior of various types of alginate fibers. The absorption characteristics of alginate wound dressings were analyzed and it was found that alginate wound dressings absorb a large quantity of liquid into the fiber structure, in addition to those held between the fibers in the textile structure. This gives rise to the unique gel blocking properties of alginate wound dressings. In addition, alginate wound dressings also have novel hemostatic and antimicrobial properties as well as the ability to promote wound healing. They are now widely used in the management of highly exuding wounds such as leg ulcers, pressure sores, and surgical wounds. Copyright © 2007 John Wiley & Sons, Ltd.
First‐trimester screening for Down syndrome; the role of nasal bone assessment in the Korean population
Authors: Moon Min Hoan , Cho Jeong Yeon , Lee Yu Mi , Jung Sung Il , Yang Jae Hyug , Kim Moon Young , Ryu Hyun‐Mee , Chung Jin Hoon , Park Seong Ho
Published: June 2007

Objectives The aim of this study was to evaluate the role of nasal bone assessment in first‐trimester screening for Down syndrome (DS) in the Korean population.

Methods From July 2004 to March 2006, we prospectively evaluated the fetal nasal bones at 11–14 weeks' gestation in the Korean population.

Results A successful evaluation was possible in 6490 of 6787 fetuses (95.6%). Absent, hypoechoic, and short nasal bones were seen in 4 (26.7%), 4 (26.7%), and 1 (6.7%) of 15 fetuses with DS, respectively, whereas in 5 (0.1%), 11 (0.2%), and 246 (3.8%) of 6456 normal fetuses. The incidence of absent and hypoechoic nasal bone showed significant differences between normal fetuses and fetuses with DS (P < 0.0005, both). Screening for DS using an absent or hypoechoic nasal bone resulted in a sensitivity of 53.3%, a specificity of 99.8%, a positive likelihood ratio of 215.2, and a negative likelihood ratio of 0.5.

Conclusion Our study showed that nasal bone abnormality at 11–14 weeks of gestation had a high association with DS in the Korean population. This suggests that nasal bone assessment can be used to supplement the current first‐trimester screening for DS in the Korean population. Copyright © 2007 John Wiley & Sons, Ltd.
Neural tube defects in the sample of genetic counselling
Authors: Joó József Gábor , Beke Artúr , Papp Csaba , Tóth‐Pál Ernő , Csaba Ákos , Szigeti Zsanett , Papp Zoltán
Published: June 2007

Objective This study was conducted to evaluate the major demographic details, diagnostical and clinical features, as well as the risk of recurrence of cases with the major types of neural tube defects (NTD). We also examined the efficiency of ultrasonography based on autopsy examinations during 26 years.

Methods The investigations were made into the sample of 743 NTD diagnosed between 1 January 1976 and 31 December 2002. A computerized database was used to sum up the available information about the individual cases; in addition to surveying the couples' major demographic details, we also had the opportunity to collect detailed information about the history, diagnostics (ultrasound) and outcome of the pregnancies as well as the results of the autopsies during the investigation.

Results In the 743 cases of NTD, maternal and paternal median ages turned out to be 23.7 years (±5.22 years) and 28.7 years (±5.81 years), respectively. The male:female ratio was 0.78. Comparable samples of anencephaly and spina bifida allowed for the conclusion that a positive genetic history was equally often found while a positive obstetrical history was almost twice as common in anencephaly. The sensitivity of the maternal serum‐alpha fetoprotein (AFP) screening test is the highest in anencephaly and lowest in encephalocele. While the majority of cases of anencephaly were diagnosed before the 24th gestational week, examples of diagnosing spina bifida and encephalocele at a later time could also be found. Among the associated malformations other than those of the central nervous system special mentioning should be made of fetal pyelectasia, cleft palate as well as diaphragmatic herniation. No pathological karyotypes were found in association with encephalocele or spina bifida, but anencephaly was accompanied with trisomy 21 and trisomy 18 in one case each. Anencephaly was found to have the highest risk of recurrence in both nervous system malformations and malformations other than those of the nervous system. Sonography proved to be the most reliable method in cases of enecephalocele.

Conclusion The respective median values of maternal and paternal age show that aetas has no role in the occurrence of NTDs. NTDs are more common among girls. Positive genetic, obstetrical and medical findings are of great importance in the incidence of NTDs. Although reliable to only a limited extent, maternal serum‐AFP tests are considered to be useful and necessary in screening NTDs, while sonography is the gold standard method in recognizing these frequent malformations. The knowledge of the eventual associated malformations is mainly important in certain cases of spina bifida, which may also yield a good post‐natal prognosis. Our data obtained from the sample of 26 years also confirm that the periconceptional administration of folic acid reduces the incidence and risk of recurrence of NTDs. Copyright © 2007 John Wiley & Sons, Ltd.
High‐ and average‐risk individuals' beliefs about, and perceptions of, malignant melanoma: an Australian perspective
Authors: Kasparian Nadine A. , Butow Phyllis N. , Meiser Bettina , Mann Graham J.
Published: June 2007

Despite expanding knowledge regarding the genetics of melanoma, there have been few attempts to define the psychosocial experiences of individuals with a family history of this disease. This study explored the ways in which individuals at varying levels of risk perceive, and respond to, melanoma. Forty semi‐structured interviews were undertaken with affected (n = 20) and unaffected (n = 20) individuals with or without a family history of melanoma. Data were analysed for potential thematic differences between risk groups, genders, and intentions to pursue genetic testing for melanoma risk. Overall, participants with a family history were in acceptance of their increased risk status and had developed ways of coping without major disruption to their daily lives. However, some participants expressed ambiguity regarding the causes of melanoma and the effectiveness of health behaviours such as sun protection. Major thematic patterns identified for those intending to pursue genetic testing were: negative emotional associations with melanoma; an emphasis on screening and sun avoidance, but not sun protection; and heightened perceptions of personal susceptibility to melanoma. In contrast, thematic patterns identified for those likely to decline testing were: ready access to stories of melanoma survival; and an emphasis on the causal role of sun exposure, whilst still believing that genetic factors may contribute to melanoma susceptibility. Compared to males, females reported a greater tendency to completely avoid the sun in order to reduce their melanoma risk. The data provide preliminary evidence for the importance of identifying misconceptions that may impede informed decision‐making about genetic testing for melanoma risk. Copyright © 2007 John Wiley & Sons, Ltd.
Evaluation of antiviral activity of South American plant extracts against herpes simplex virus type 1 and rabies virus
Authors: Müller Vanessa , Chávez Juliana H. , Reginatto Flávio H. , Zucolotto Silvana M. , Niero Rivaldo , Navarro Dionezine , Yunes Rosendo A. , Schenkel Eloir P. , Barardi Célia R. M. , Zanetti Carlos R. , Simões Cláudia M. O.
Published: June 2007

This paper describes the screening of different South American plant extracts and fractions. Aqueous and organic extracts were prepared and tested for antiherpetic (HSV‐1, KOS and 29R strains) and antirabies (PV strain) activities. The evaluation of the potential antiviral activity of these extracts was performed by using an MTT assay for HSV‐1, and by a viral cytopathic effect (CPE) inhibitory method for rabies virus (RV). The results were expressed as 50% cytotoxicity (CC50) for MTT assay and 50% effective (EC50) concentrations for CPE, and with them it was possible to calculate the selectivity indices (SI = CC50/EC50) of each tested material. From the 18 extracts/fractions tested, six extracts and four fractions showed antiviral action.Ilex paraguariensis, Lafoensia pacari, Passiflora edulis, Rubus imperialisandSlonea guianensisshowed values of SI > 7 against HSV‐1 KOS and 29‐R strains andAlamanda schottiishowed a SI of 5.6 against RV, PV strain. Copyright © 2007 John Wiley & Sons, Ltd.
Beneficial effects of Centella asiatica aqueous extract against arsenic‐induced oxidative stress and essential metal status in rats
Authors: Flora S. J. S. , Gupta Richa
Published: June 2007

The efficacy of an aqueous extract of Centella asiatica (100, 200 and 500 mg/kg for 5 consecutive days) was studied in the depletion of arsenic and in the recovery of a few altered biochemical variables in arsenic pre‐exposed rats (20 ppm in drinking water for 5 weeks). Exposure to arsenic significantly depleted δ‐aminolevulinic acid dehydratase (ALAD) activity, reduced glutathione (GSH) level, superoxide dismutase (SOD) and increased thiobarbituric acid reactive substance (TBARS) activity in red blood cells. Significant depletion of ALAD activity, GSH level, glutathione peroxidase (GPx), SOD and catalase (CAT) activities and an increase in TBARS levels in liver tissues was also noted. There was a significant depletion of SOD, CAT and GPx activities in kidneys and an increased TBARS levels in kidney and brain accompanied by increased arsenic concentration in blood and soft tissues. Treatment with aqueous extract of Centella asiatica provided significant protection against ALAD, GSH and TBARS levels, particularly at doses of 200 and 500 mg. Centella asiatica also provided significant recovery in the inhibited liver ALAD and G6PD activities. Arsenic concentration in blood and soft tissues remained uninfluenced after Centella asiatica administration. The present study thus suggests a beneficial effect of Centella asiatica against arsenic‐induced oxidative stress but possesses no chelating property. Copyright © 2007 John Wiley & Sons, Ltd.
Measurement of microelectroretinogram by photodiode stimulation
Authors: Jiang Xin , Morita Tatsuya
Published: July 2007

The electroretinogram (ERG) is considered interesting not only as a diagnostic information in the ophthalmological clinics but also in biological engineering as a clue to the opto‐electric conversion mechanism in the retina. Conventionally, ERG is observed using the whole field stimulation of the retina by a strong flash, where the information concerning the local activities of the retina cannot be obtained. Another point in ERG is that the analysis is difficult due to the nonlinearity and the ambiguity of the stimulus waveform. This paper proposes a new method which analyzes the frequency characteristics of the micro‐ERG (μ‐ERG), evoked by the stimulation using the light‐emitting diode (LED).

This method has the following advantages: the stimulating waveform can be controlled arbitrarily; the method of linear system analysis can be applied; the local stimulation can be realized; and the color sensation can be examined.

This paper discusses two basic techniques in the detection of the μ‐ERG. One is the Fourier analysis of the synchronized ERG evoked by the sine wave stimulus, and the other is the correlation analysis using the random stimulus. The results of the two methods are compared, and the usefulness of the proposed method is indicated.
Understanding mechanical assembly illustrations‐obtaining assembly information from auxiliary lines showing assembly relations
Authors: He Shoujie , Kitahashi Tadahiro , Abe Norihiro
Published: July 2007

Assembly illustrations are drawn usually in an assembly manual to show assembly information because, in many cases, instructions cannot show assembly information unambiguously enough. Therefore, it is necessary to combine the assembly information both from instructions and illustrations so that unambiguous assembly information is obtained finally. Naturally, it becomes necessary to construct a cooperative system for image understanding and language understanding. For such a final purpose, the purpose of this study is to obtain assembly information only from illustrations by means of image understanding.

This paper presents an approach for obtaining assembly information from illustrations. As an example, the approach takes an auxiliary line employed to show an assembly relation between two certain mechanical parts. By extracting auxiliary lines and using the information on the location and orientation of these lines, we can recognize not only the assembly relations but also the structure of mechanical parts, especially such structural details as the invisible or occluded holes. Further, the assembly order can also be conjectured to some extent from an illustration in which several assembly relations are shown simultaneously. By taking advantage of the foregoing information, the system can decide whether an object is equal to the assembly constructed from the given illustration.
On finding the axes of skewed symmetry using the image normalization with moment
Authors: Yoshikawa Toshinori , Iida Izumi
Published: July 2007

Among the reconstruction methods for three‐dimensional information, methods are known for extracting the axes of skewed symmetry that place constraints on the orientation of the plane in space. Since skewed symmetry loses the symmetric nature for the most part, the many earlier methods for extracting axes of symmetry could not be directly applied to extracting axes of skewed symmetry. In addition, conventional methods for extracting the axes of skewed symmetry have the drawbacks of having long processing times and being difficult to apply to complex figures. In this paper, we propose a method that uses moments to perform a first‐order transform on a skew symmetric figure into a symmetric figure and then extracts the axes of symmetry. In this method, the problem is simplified by transforming a skew symmetric figure into a symmetric figure so that conventional methods for extracting the axes of symmetry can be applied. In addition, the evaluation of symmetry which uses the fact that the areas on both sides of an axis of symmetry are equal is adopted in the proposed extraction of the axes of symmetry. The features of this method are discussed by giving practical examples of extracting the axes of skewed symmetry.
Modeling a three‐dimensional shape from a silhouette by detecting symmetry
Authors: Fukushima Shigehiro , Okumura Takeshi
Published: July 2007

A human being, observing a silhouette outline of an object, can estimate its three‐dimensional (3‐D) shape. This process has implications for the problem of recognizing and understanding 3‐D shapes, since a similar process is needed in 3‐D shape modeling of computer graphics.

One idea for such 3‐D shape modeling is to generate generalized cylinders on the basis of symmetry of the silhouette. This means finding symmetrically related pairs of points on the outline and estimating cross sections of the object from line segments connecting respective pairs of points.

A generalized cylinder for the object can be constructed from the set of such cross sections. However, the symmetric point pairs previously were extracted by heuristic methods, and some instability was involved.

This paper applies a recently proposed method of computing symmetric point pairs based on geometric division of the plane to 3‐D shape modeling. Two ways to develop it are proposed: (1) prune it if the symmetric axis has branches, thereby generating a generalized cylinder for the trunk; and (2) generate generalized cylinders for the trunk and for respective branches, thereby modeling a complex shape as a self‐intersecting object composed of multiple segments. The segment decomposition is implemented by natural reasoning.
A study of distributed environment for three‐dimensional image processing using extended server‐client model
Authors: Okada Minoru , Yokoi Shigeki , Toriwaki Jun'Ichiro
Published: July 2007

One method for constructing a distributed image processing environment for three‐dimensional digital images is examined. VISUAL, which is proposed here, is based on an extended client/server model. Specifically, an image processing system is constructed from one server that manages the images and clients that correspond to the processing units in a series of image processes. VISUAL offers a platform where multiple client processes cooperate and operate under a server. In this paper, the basic overview, design objectives, and implementation are explained. In addition, the effectiveness of more efficient development of image processing systems by distributed functions and program hiding is demonstrated.
Organization of a real‐time operating system “A‐RMS”
Authors: Yokohata Shizuo , Sugita Yumiko , Aoki Hisanobu , Ishikawa Tomoo
Published: July 2007

As technologies in the process control and the equipment control fields become more and more advanced, there are increasing needs for a real time operating system which provides the interactive processing function in addition to the conventional control function.

In the past, as a means to cope with these needs, technologies such as the virtual machine system of the emulation system were proposed. However, these systems presented difficulties in handling because each environment in these conventional systems uses its own operating system interface.

This paper describes “A‐RMS,” a newly developed real‐time operating system which incorporates an interactive processing function as native on top of a real‐time operating system providing a control function. The control function and the interactive processing function are realized with unified concept and specification in A‐RMS. Adverse effects on the control function which might be induced by the incorporated interactive processing function are prevented by introducing a concept of environment to separate the interactive processing function from the control function.

The new operating system is implemented on the M68010. This paper also mentions the effect of incorporation of the interactive processing function on A‐RMS performance. To secure response, A‐RMS employs only the real memory. The memory management unit (MMU) is used exclusively for memory protection.
A parallel algorithm for tree pattern matching
Authors: Tarora Koji , Hirata Tomio , Inagaki Yasuyoshi
Published: July 2007

Given a text tree t and a pattern tree p, tree pattern matching involves finding subtrees of t which match p. This paper proposed a parallel algorithm for tree pattern matching. The algorithm is designed to run in O(log n) parallel time using mn/logn processors on CREW‐PRAM, where n and m are the sizes of t and p respectively. This improves the result of Ramesh et al. that runs in O(log2n) time using nr/log2n processors, where r is the number of vertices of p labeled with variables. Futhermore, the method of processor allocation is described specifically in the proposed algorithm.
Multi‐valued current‐mode parallel multiplier based on redundant positive‐digit number representations
Authors: Kaqahito Shoui , Ishida Makoto , Nakamura Tetsuro , Mizuno Kentaro , Kameyama Michitaka , Higuchi Tatsuo
Published: July 2007

This paper proposes a new parallel multiplier based on the redundant number representation using positive digits (called redundant positive‐digit number representation, or simply PD number representation). The proposed algorithm is the fastest algorithm that can execute the multiplication of n x n digit by a time proportional to log2n. The structure is regular and is suited to LSI implementation.

The proposed parallel multiplier is designed in two ways, i.e., by the multivated current mode circuit and by the binary digital circuit. Then the results are evaluated. The circuit designed by the multivated current mode, especially, has the feature that the 6‐input addition with partial product operand can be executed by the wired addition and a single‐stage parallel adder based on the PD number representation. Thus, it is demonstrated that the circuit has a high speed and can be realized with a very small number of elements and wirings. The basic circuits for the proposed parallel multiplier are constructed experimentally by 5 μm CMOS technology, and a satisfactory performance is verified.
Development of an expert system for recognizing handwritten dollar amounts
Authors: Kameyama Hirofumi , Miki Shoji , Suzuki Hisashi , Arimoto Suguru
Published: July 2007

This paper presents an expert system for automatically recognizing handwritten characters of dollar amounts on personal checks. The dollar amounts composed of numerals and marks—, “X X,” etc., are freely handwritten in various formats that individuals favor, inside the amount field. Then frequently there is contact between not only horizontally adjacent characters but also vertically adjacent ones. Recognition of such unconstrained character strings handwritten by the public whose formats are undecided beforehand is a problem in optical character recognition.

The system developed in this paper has the ability to segment the dollar amount image into individual characters automatically and to recognize them accurately. The recognition process of the dollar amount consists of the following steps: divide a digitized image into groups, called a “block,” of line elements connected with one another; give attributes to each block by using the knowledge on arrangement patterns of characters; and segment the block into individual characters according to the attributes and recognize them. It is suggested that this system will enable the saving of considerable operator labor in check processing.
A static processor‐scheduling algorithm resistive to dynamic fluctuation of execution timing
Authors: Takagi Hiromitsu , Arita Takaya , Sowa Masahiro
Published: July 2007

The feature of the parallel computer, where the tasks are allocated to the processors at the compiling stage, is that the control at the execution stage is simplified. Thus, a high‐speed execution is expected. However, a problem may arise when the processing of each task cannot accurately be estimated before the execution due to the uncertainty such as the delay in the network or the cache‐miss, making the performance deterioration inevitable.

In the allocation of more than one executable task to the idle processors in the conventional scheduling algorithm, it is not particulary specified which task is allocated to which processor. This paper notes the forementioned point, and attempts to suppress the performance deterioration to the minimum by deciding the foregoing point by an adequate algorithm. More precisely, the basic idea is to reduce the precedence constraint by allocating two tasks with precedence constraint to the same processor.

A new scheduling algorithm is proposed and is evaluated using a number of task graphs. It is shown that the speed improvement of 4 to 16 percent can be achieved, compared to the conventional algorithm.
Optimal number of processors in parallel processing of a single doacross loop for different execution times of iterations
Authors: Fukuda Akira
Published: July 2007

In most of the past theoretical studies of the parallel processing of the loop, the discussion developed assuming that all execution times of the iterations are the same. Especially, the discussion is always developed under such an assumption for the doacross loop, which is the general loop processing model, including the doall and doserial loops. Considering the multiprocessor memory architectures at present and in the future, however, the following assumption seems more adequate.

In each of the processors participating in the loop processing, the execution times of the second and the following iterations are shorter than that of the first. Under this assumption, there exists the number of processors (called the optimal number of processors) that minimizes the loop processing time.

This paper considers the single doacross loop, and discusses the following loop processing: (1) after the delay time of d from the start of execution of the i‐th iteration Ii, the next iteration Ii+1 is permitted; (2) the iteration that once started its execution is never preempted until the execution is completed; (3) for each processor participating in the loop processing, let the execution time for the first iteration be B, and that of the second and the following iterations be b. Then, d < b < B. This paper derives the optimal number of processors for the forementioned model.
Relationships between learning and information compression based on PAC learning model
Authors: Takimoto Eiji , Maruoka Akira
Published: July 2007

This paper is based on the concept of the learning function, which represents the input‐output relation of the learning algorithm. The learning process and the information compression process are formulated as the PAC learning function and the Occam function, respectively, and their equivalence is discussed. It is shown that the Occam function is always a consistent PAC learning function, while its converse is not always true.

The weak Occam function which is obtained by weakening the condition concerning the information compression power of Occam function is defined anew and it is shown that the weak Occam function is always a consistent PAC learning function. Furthermore, a procedure is shown which derives the weak Occam function from the PAC learning function under a certain condition.
A neural fuzzy training approach for improving speech recognition
Authors: Komori Yasuhiro , Sagayama Shigeki , Waibel Alexander H.
Published: July 2007

This paper proposes a new training method for the phoneme identification neural network called “neural fuzzy training.” In the proposed training, nondeterministic (fuzzy) class information is assigned to the training signal, in contrast to the traditional method where a deterministic class information is assigned.

This study aims at the realization of a robust neural network, thereby improving the cumulative recognition rate of the phoneme identification and avoiding overtraining. The proposed neural fuzzy training is realized by backpropagation. In the conventional training, a deterministic phoneme class information is assigned to the training signal of the neural network as the value 1 or 0. However, in the proposed training, the fuzzy class information is assigned to the training signal for each training sample as the likelihood value between 0 and 1.

In the proposed training method, the likelihood is calculated by the monotonically decreasing function (such as exp(−α · d2)) of the distance between the training sample and the closest sample belonging to each phoneme class. The proposed neural fuzzy training method has a problem in that a large amount of computation cost is required since the training signal is determined by calculating the distances to all training samples. To solve this problem, the representative samples in each phoneme class are defined and the likelihood to the phoneme classes are determined by calculating the distance between the representative sample and the training sample.

By this simplification of the likelihood calculation, the computational cost to determine the training signal is reduced considerably. To demonstrate the usefulness of the neural fuzzy training, an experiment is conducted: /b, d, g, m, n, N/ identification, 18 consonant identification and phrase recognition using TDNN‐LR. The ATR database is used in the experiment. In the phoneme identification experiment, the speech samples which are extracted using the hand‐label is used. The TDNN is trained using speed samples uttered in word style, and the evaluation is performed using speech samples uttered in phrase style and in sentence style.

In the phrase recognition experiment using TDNN‐LR, the TDNN is trained using speed samples uttered word style using a hand label. The evaluation is performed using speech samples uttered in phrase style. In either experiment, an improvement of using the fuzzy training can be observed. Especially, in the phrase recognition experiment using TDNN‐LR, the top recognition rate is improved from 71.2 percent to 80.9 percent, and the top 5th recognition rate is improved from 92.8 percent to 96.O percent. Furthermore, it appeared also that the neural fuzzy training is a high‐speed training method.
Interactive 3‐dimensional segmentation method based on region growing method
Authors: Sekiguchi Hiroyuki , Sano Koichi , Yokoyama Tetsuo
Published: July 2007

It has become easy to obtain three‐dimensional (3D) data of the inside of the human body because of developments in X‐ray computed tomography (CT) and magnetic resonance imaging (MRI). The 3D images of internal organs constructed from these data are useful in understanding the 3D shapes and positional relationships of the organs and are expected to be the diagnostic images of the next generation. However, many problems remain to be solved in making them practical, such as, improving the display speed of 3D images and implementing a 3D interface. For MRI, in particular, the difficulty in segmenting the display image is becoming a major impediment to the practical use of 3D MRI images. In this paper, we propose a practical segmentation method in which interactive corrective operations for 3D images are included in 3D region growing. To implement this method, we developed a 3D monitoring function for the segmentation process and an automatic function for removing the leaks generated during region growing. This method was applied to several 3D MRI data of the head and its effectiveness was confirmed.
Speech synthesis from concept representation in general speech output interface
Authors: Yamashita Yoichi , Mizoguchi Riichiro , Mizutani Naoki , Kakusho Osamu
Published: July 2007

The goal of this paper is to realize natural and high‐quality speech output from various problem‐solvers implemented on a computer. The framework for the general speech output interface is discussed, and the basic architecture is designed for SOCS (Speech Output from Case Structure representation). This is the speech synthesis system based on the concept representation converting the input to the interface into speech. The important issue in such a framework is to define a mechanism to transmit information from the problem‐solver to the speech output interface.

From such a viewpoint, the representation based on the case structure and the phrase patterns is defined as the concept representation to describe the inputs to the interface and the speech synthesis system from the standpoint of problem‐solver, speech synthesis, and the dialogue management. The concept inputted to the interface is modified by the dialogue manager and is converted into the speech by SOCS. In SOCS, the prosody as well as the sentence is generated based on the concept representation. The pause markers generated in the sentence generation determine the positions of the pause and the Fϕ resetting. The prosodic patterns also are generated by the prosody modification function described in the custom template.
Performance improvement of jukebox‐type optical disk file system
Authors: Takahashi Naoya
Published: July 2007

This paper proposes an image data prefetch method for improving the performance of client/server optical disk file systems that use a jukebox‐type optical disk equipment. The frequent optical disk replacement of the jukebox has been the cause of the delayed data access of the file server, and an intolerable long response time at workstations.

To reduce the frequency of disk replacement, the proposed method prefetches a series of image data from the file server to workstations for possible later displaying or printing. This method is implemented in a commercial system, and its performance is better in comparison with a conventional system. A concurrent processing function also is implemented in the file server. It enabled a waiting time for the disk replacement to be used for the services for other workstations. This also contributed to an additional performance improvement.
A fast motion planning algorithm for a mobile robot using a distance transformation image
Authors: Shin Donguk
Published: July 2007

This paper proposes a new high‐speed motion planning algorithm for the mobile robot functioning on the distance‐transformation image. The method utilizes the property that the value of the distance transformation image represents the distance from the obstacle. By the proposed method, the robot can move by translation to the farthest possible point only by examining a small number of points on the straight‐line of the progress. This makes it possible to realize the fast motion planning. When a deadlock is produced, a new posture of the robot is determined at the position so that the collision with the obstacle does not occur. Then, the part of the motion down to the initial point is regenerated.

Finally, the speed of the proposed algorithm is compared to that of the conventional motion planning algorithm, and the fast operation is demonstrated experimentally.
Circuit complexity of slice functions and homogeneous functions
Authors: Hirose Shoichi , Yajima Shuzo
Published: July 2007

This paper discusses the complexity from the viewpoint of the number of circuit elements for the slice functions and the homogeneous function, which belong to the class of monotonic logic functions. The slice function is one of those functions in which the circuit complexity is almost equal to the monotonic circuit complexity.

The n‐input k‐homogeneous function is considered as the first step, and it is shown that there exists a function with the k‐slice monotonic circuit complexity Ω(nCk/lognCk)and the monotonic circuit complexity of u(> k) slice is O(nlogn). This property has already been shown by Wegener for the case of the k‐slice with the monotonic circuit complexity Ω(n‐1Ck‐1/logn‐1Ck‐1). The result in this paper is an improvement of his result, and is the optimal when k is a constant.

As the next step, a homogeneous function is shown where the monotonic circuit complexity is almost equal to the circuit complexity. As in the case of the slice function, if the lower bound ω(n(logn)2) for the monotonic circuit complexity for the n‐input homogeneous function is shown, the same lower bound is shown for the circuit complexity.
A new element for parallel distributed processing network—learning distance product element
Authors: Murayama Satoshi , Yokoi Hirokazu
Published: July 2007

One of the factors which affect the convergence velocity in the learning by a parallel distributed processing network is the input/output characteristic of its elements. This paper proposes anew a learning distance product element to substitute for the conventional learning threshold elements, and performs the computer simulation of a three‐layered network with two inputs and one output using the learning distance product elements. As a result, it is confirmed that on average, learning is accelerated compared to the use of the learning threshold elements.
Experimental studies of memory surfaces and learning surfaces in recurrent neural networks
Authors: Watanabe Tatsumi , Uchikawa Yoshiki , Gouhara Kazutoshi
Published: July 2007

The following approach is considered to be important for an insight into the “learning” in the layered network. The adjustable parameter vector w satisfying the required input‐output relation of the network also is considered. Then the “memory surface” in w space formed by the set of solutions for the nonlinear equation for w should be investigated. It is shown also that the idea of the “memory surface” can be extended to the learning of the recurrent network (abbreviated as RNN) with a supervisor.

This paper shows the following property by an experiment. When the evaluation function E is defined by the square integral of the error, then the behavior of RNN agrees essentially with the results obtained for the case of the layered network in the following four points: (1) there exists the memory surface in RNN in the same way as in the layered network; (2) the supervised learning of RNN amounts geometrically to the search in the intersection region of multiple “memory surfaces” for the global or local minimum of E on the learning surface formed in w‐E space with w as the variable; (3) the feature of the learning surface of RNN is that the space is composed of a long “valley” and a flat “hill” with smaller gradient; and (4) the learning process by the successive search based on the gradient vector of E tends to progress near the memory surface along the valley.
Three‐dimensional blood vessel reconstruction using a high‐speed X‐ray rotational projection system
Authors: Kawata Yoshiki , Niki Noburu , Satoh Hitoshi , Kumazaki Tatsuo
Published: July 2007

The feature X‐ray angiography is that a blood vessel image with a high spatial resolution is obtained. Consequently, it is a decisive diagnostic tool for the pathology of the blood vessel. However, its precision is still sufficient for the diagnosis of blood vessels with delicate aneurysm or stenosis, as well as for planning surgery. Thus, it is desired to develop further an imaging method for the blood vessel configuration with a higher precision.

This paper describes a precise observation method for the blood vessel configuration, where a pair of X‐ray source and the image intensifier (II) with a high‐speed rotation is used to scan and derive multidirectional projection images, and the blood vessel configuration is reconstructed in three‐dimensions for high‐precision 3D observation. As a pre‐processing to the reconstruction, the image distortion correction for II as well as the estimation of the camera coordinate are executed.

In the 3D reconstruction of the blood vessel, the filtered backprojection method is used with the short‐scan (details are discussed later) cone‐beam projection. The result of 3D reconstruction of the blood vessel can be observed by the 3D display and the 3D model for the blood vessel configuration. The method is applied to the actual projection image of the cerebral blood vessels, and the effectiveness is demonstrated. By this method, a highly precise measurement of the blood vessel shape is realized, which has not been observed by the past technique, and the configuration of the blood vessel can be analyzed in the 3D space. It is expected that the proposed method with those features will be utilized in the quantitative diagnosis of the cerebral blood vessel diseases and treatment planning.
Detection of unfeasible paths with a path‐dependence flow graph
Authors: Naoi Kuniaki , Takahashi Naohisa
Published: July 2007

The problem of finding unfeasible paths (UFP: computation paths that are never executed for any input) is important in test data generation and effect propagation analyses. In this paper a directed graph representation executable in parallel, called path dependence flow graph, is proposed which is suited to problems of finding properties of procedural programs along computation paths such as the UFP detection problem.

Also, a method is given that symbolically computes logical expressions necessary for UFP detection by parallel abstract interpretation of this graph. Furthermore a method for detecting UFP is presented that converts an obtained logical expression into a Presburger sentence and that applies a truth value decision method for Presburger sentences to it. By using this method, the computation control is made simple and the removal of computations that are not necessary for UFP detection is made easy. In addition since partial results can be shared, UFPs are detected more efficiently.
Recognition of handwritten character database ETL9B using pattern transformation method
Authors: Guo Jun , Sato Risaburo , Sun Ning , Nemoto Yoshiaki
Published: July 2007

To enhance the recognition rate of handwritten characters, one has to consider the effects of various changed forms in character patterns. In Reference [1], we have proposed a recognition algorithm using pattern transformation, which can deal flexibly with the changed forms in character patterns. In the fine classification, the algorithm makes three types of pattern transformations for the input pattern, and selects the transformed pattern that matches the standard pattern best. This paper improves that algorithm and constructs a recognition system. As the results of testing with ETL9B, a database of handwritten characters that contains 600,000 Japanese characters and a recognition rate of 96.32 percent was achieved, a new record for ETL9B.
Methods for choosing a training set which prevents over‐learning
Authors: Yamasaki Kazutaka , Ogawa Hidemitsu
Published: July 2007

A drawback of the error‐backpropagation method for a multilayer feedforward neural network is overlearning. The authors have already discussed this problem, and obtained necessary and sufficient conditions for over‐learning to occur. Using those conditions and the concept of a reproducing kernel, this paper proposes methods for choosing a training set which prevents over‐learning.

First, the case is discussed in which pure training data are available. Methods are presented for choosing a training set so that a memorization learning does not cause Wiener over‐learning. Next, the case in which noisy training data are available is discussed and methods for choosing a training set so that a rote‐memorization learning does not cause Wiener overlearning are shown.