bluuebunny/crossref_metadata_2025 huggingface dataset:
A method for generating program specification from source program—analysis by transforming program structure and argument manipulation
Authors: Nagai Takahiro , Imanaka Takeshi , Toyoda Jun'Ichi , Hirashima Tsukasa , Uehara Kuniaki , Nagasawa Yuichi
Published: July 2007

This paper proposes a method of transformation analysis for the automatic generation of program specification from the source program. The system APSG/I (Automatic Program Specification Generator I), on which the proposed method is implemented, is discussed. The transformation analysis notes the similarity to the list‐processing program of Prolog. By utilizing the framework of analogical reasoning, the specification for the given program is generated based on the typical list‐processing programs and its specification.

When the program is inputted, the following two aspects are examined and the difference is determined by comparison with the already defined typical program: 1 the structure specified by the existence of the command or the order of the execution; and 2 the combination of arguments specified by the passing of data, etc. Then based on the determined difference, the already defined program specification is transformed, and the specification for the inputted program is generated. The specification generated by the proposed transformation analysis has the following features: 1 the result is the natural language sentence, since the program specification and the transformation rule for the specification are defined by the natural language; and 2 the format is unified and sufficient information to the details is contained.
Artifact cancellation in MRI due to phase encoding axis motion
Authors: Tang Li , Ohya Muneki , Sato Yoshinobu , Tamura Shinichi , Naito Hiroaki , Harada Koushi , Kozuka Takahiro
Published: July 2007

This paper addresses the problem of motion artifact cancellation in the standard 2D‐FFT MRI. Although motion is possible in any direction, in clinical MRI diagnosis, respiration is considered to be the main cause of motion. As a first order of approximation, motion due to respiration is assumed to be only in the phase‐encoding direction (Y‐axis) in this paper. In the previous approach, the region of a target object is assumed to be known and an iterative procedure is required. The problem of the algorithm is the convergence of the iterative (which may take a lot of time) and still has no guarantee of convergence. To avoid an iterative procedure, a new constraint is proposed here, with which the motion component and the true image component can be separated by a simple algebraic operation. After the Fourier transform of MRI signal along the read‐out direction (X‐direction), the phase of the spectrum along Y‐axis is expressed as an algebraic sum of the motion component and the true image component. On the other hand, when density distribution is symmetric along a Y‐direction line, such as a slice line on subcutaneous fat, the phase of the Fourier spectrum along the line is a linear function of Y‐position. Therefore, if the density is symmetric, the departure from the linear function of the phase is just the motion component. With this constraint the motion component can be estimated and the motion artifact in MRI can be canceled. The algorithm is shown to be effective using a phantom with simulated motions in various cases. When the density distribution along the Y‐directional line on subcutaneous fat is not perfectly symmetric, the accuracy of estimated motion will be affected to some extent. However, this method is shown to be still effective in such general case by simulations.
An interactive analysis method for multidimensional images using a Hilbert curve
Authors: Kamata Seiichiro , Kawaguchi Eiji , Niimi Michiharu
Published: July 2007

To analyze multidimensional images we need a mapping of feature vectors from a multidimensional space to a lower dimensional space. In general, these are performed using linear transformation methods, such as principal component analysis, etc. Linear transformation requires many rotations of data from several points of view because the mapping is not one‐to‐one. Here, a new interactive method for classifying multispectral images using a Hilbert curve is presented. The Hilbert curve is a one‐to‐one mapping from N‐dimensional space to one‐dimensional space and preserves the neighborhood as much as possible. Hilbert curve is a kind of space filling curves, and provides a continuous scan. The merit of the system presented is that the user can extract category clusters without computing any distance in N‐dimensional space easily. The method presented here is explained in brief. Clusters are extracted from 1‐D data mapped by a Hilbert curve interactively, i.e., a pixel is classified as a category. The user can analyze multidimensional images hierarchically from gross data distribution to fine data distribution. To realize the real time response from the system, data tables storing the addresses and the occurrences of data are used. Here, the address is defined by using the coordinates in N‐dimensional space, and a part of mapping which cannot preserve the neighborhood is utilized. In the experiments ex‐extracting categories from LANDSAT data, it is confirmed that the user can obtain the real time response from the system after once making the data tables.
Problem‐solving SCRIPT and classification of drawings for explaining human drawing processes
Authors: Ito Takeshi , Ohnishi Noboru , Sugie Noboru
Published: July 2007

Several of the most recent studies of the recognition model have attempted to describe the mechanism involved in the human drawing process. Any clear‐cut interpretation is at this date still problematic. A recognition model (DIPS) has been constructed that simulates the human drawing process; the goal is a model that includes the drawing process as a part of problem‐solving. To date, the model contains only a single drawing process and has not reached the point at which all drawing processes in various problem‐solving stages can be described.

In this study, the drawings made as a part of the problem‐solving procedure are divided into 8 classes according to their appearance. Which of these drawings appears at what stage of the problem‐solving procedure is investigated in detail using psychological experiments. The “problem solving SCRIPT” is proposed as a concept to describe the drawing process. It is shown through psychological experiments that the concept of “problem‐solving SCRIPT” is observed, not only in the theorem‐proving endemic to geometry, but also in mathematical problems written in context and problems in physics. The drawings that are observed in each stage of SCRIPT are examined and then the relation between SCRIPT and the drawing is described according to the purpose in each stage.
A quasi‐competitive network with transition between models
Authors: Kindo Toshiki
Published: July 2007

This paper proposes a quasi‐competitive network in which the mass reaction intensity of the elements in the intermediate layer is kept constant as a model that approximates the continuous nonlinear function. As the loss function, the local loss function is considered. It is composed of the error and the local model loss term reflecting the local model size.

The learning algorithm of the quasi‐competitive network including the change of the number of elements is derived from the local loss function. It is shown by numerical experiment that the quasi‐competitive network can form quickly the structure reflecting the target function and has a high generalization power. It is shown also that the high generalization power is due to the constant mass reaction intensity of the elements in the intermediate layer of the quasi‐competitive network.
Construction of structural edge map on chest radiograph using hough transformation and line connection
Authors: Sugahara Tetsuo , Yanagihara Yoshio , Sugimoto Naozo
Published: July 2007

For computer diagnosis of a chest radiograph, we propose a method to make a structural edge map consisting of subclaviculars, heart, diagram, and ribs that have been extracted from a chest radiograph. On processing, the intensity of the edges of an input image was calculated by a derivative filter. Next, the possibility of lines and/or arcs was calculated by Hough transformation. This transformation was applied to 13 small areas for each of the organs in the image. A reconnection of lines and arcs representing the edges of the organs was performed, and a structural edge map was then constructed. As a result detection of subclaviculars, heart, diaphragms, and inferior edge lines of ribs was very good (ge; 79 percent). However, detection on superior edge lines was poor (= 55 percent).
Fault‐tolerant associate memories
Authors: Fujiwara Eiji , Tanaka Tsuyoshi
Published: July 2007

Because of its capability of high‐speed search, the associative memory (CAM) is expected to be used in a variety of information processing systems. In this paper, novel fault‐tolerant techniques which are effective for on‐line use are proposed for TLB which is an example of the application of CAM.

First, fault and error models of the TLB consisting of the CAM part and the SRAM part are clarified. Then, the fault‐tolerant techniques for these faults and errors, such as distance separable technique, cod‐ing technique, simplified 1‐out‐of‐n check and graceful degradation, are proposed. The distance separable technique which encodes the data stored in the CAM part is the one which masks the faulty CAM part and prevents errors from propagating to the subsequent circuits. The coding technique checks the one‐to‐one correspondence between the data in the CAM and those in SRAM by using the SEC‐DED code with byte error detection capability, i.e., SEC‐DED‐SbED code, and at the same time it detects and corrects errors in the data stored in SRAM. The simplified 1‐out‐of‐n check processes association errors. The graceful degradation gives a flag in the faulty memory section and prevents it from being used.

The methods proposed in this paper are evaluated from area augmentation and error detection capability perspectives. The results show that the fault‐tolerant TLB with 32 virtual address bits, 32 physical address bits and 128 entries gives single fault detection probability of nearly 99 percent with 28 percent area increase.
An algorithm for affine transformation of binary images stored in pxy tables by run format
Authors: Shoji Kenji
Published: July 2007

The algorithm for an affine transformation (such as magnification, reduction, or rotation of a binary image) using a run format and a combination of a skew transformation and a transposition has been known. A transposition using this conventional algorithm requires a relatively large amount of computation time, although its skewing operation is simple and fast.

This paper proposes an efficient method of transposition of an image represented by a run format, and its applications to an affine transformation (e.g., rotation, magnification, and reduction of an image). The proposed method uses a simple run data format “pxy tables,” in which the start coordinate of black and white runs are stored alternatively in a one‐dimensional array. An experimental comparison of the proposed method with a conventional method shows that the computation time per run of the former is constant, while that of the latter increases with the length of the black runs. In other words, the computation time of an affine transformation of a binary image by using the proposed method is approximately proportional to the number of runs alone.
How local image velocity is detected by cells on the magnocellular pathway of the visual cortex
Authors: Kawakami Susumu , Okamoto Hiroaki
Published: July 2007

Recent anatomical studies have clarified that local image velocity is detected by a sequence of cells on the magnocellular pathway of the visual cortex. To the authors' knowledge, however, neither neurophysiological nor theoretical studies have been able to clarify the roles of these cells in velocity detection.

The authors propose that the cell sequence constitutes a function hierarchy for detecting velocity. Lateral geniculate nucleus cells first introduce a time delay. They are followed by two simple cell types that perform a Hough transform and a spatio‐temporal correlation. Complex cells then perform an accumulation to convert the velocity into a sine wave composed of activated cells in the complex cell array. The amplitude and phase of the wave correspond to the velocity speed and direction components. Finally, motion‐detection cells in the middle temporal area perform an inverse Hough transform to extract the wave.

Five types of cells are modeled as a series of formulas that represent the synaptic functions of neurons. The modeled cells exhibit the same selectivities to stimuli as actual cells. They detect the velocity from various moving stimuli, including dots, straight lines and curves.
Construction of a reusable knowledge base—Generating operation sequences for the accident restoration of primary substations based on the reusable knowledge base
Authors: Zhang Qianren , Sakamoto Morihiro , Kidokoro Kazuaki , Mizoguchi Riichiro , Takaoka Yoshiyuki , Yamashita Masatosi , Hirobe Kenji
Published: July 2007

The expert systems (ES) in the past have mostly been constructed to solve particular problems, and it is difficult to share or reuse the obtained knowledge. This has been a serious drawback in efficiently constructing an ES. Since practical application of ES is in progress, and the practical usefulness is recognized widely in society at present, it is very significant to work for sharing reuse of knowledge.

The authors considered the accident restoration assist of the primary substations, and attempted to construct a reusable knowledge base. In this paper, first, the conventional ES to assist the accident restoration of the primary substations is analyzed, and it is pointed out that the knowledge is restricted to particular substations and, consequently, cannot directly be reused. Then the methodology for constructing the reusable knowledge base is discussed.

Based on the presented methodology, the constructing procedure for the reusable knowledge base for the accident restoration of the primary substations is discussed in detail. The knowledge of the expert in problem‐solving is analyzed and is divided into the following three classes: 1) the object model; 2) the general rules; and 3) the knowledge specific to the particular primary substations.

Finally, the procedure‐generation system for the accident restoration of the primary substations is described. Through the test using the case data of 10 accidents in 2 primary substations, it is verified that the same operation sequence can be generated as the one by the expert.
Application of abduction to computer bridge
Authors: Uehara Takao
Published: July 2007

This paper proposes a method using the hypothetical reasoning for locating missing high cards in the game of bridge. Beginner knowledge for bidding and leading cards is represented by constraint logic programming language CHIP. Observation as to whether one leads with the king of hearts is given as a part of query. Then hypothesizing as to the possession of the ace of hearts is generated by abduction and integrity constraints are checked by consistency techniques in CHIP. A system based on beginners' knowledge is as powerful as an expert system used for the same purpose.
A wavelet neural network with network optimizing function
Authors: Kobayashi Kunizaku , Torioka Toyoshi , Yoshida Nobuo
Published: July 2007

A new mapping network combining wavelets and neural networks is proposed. The proposed network has three major characteristics, namely, self‐construction of neural networks, partial retrieval of the approximate mapping, and efficient learning. The network learning algorithm can be divided roughly into the self‐construction process and the error minimization process. In the first process, hidden units are appended serially in such a way that the network structure sufficiently approximates the approximation target. Simultaneously, network parameters are updated by competitive learning. In the second process, network parameters are updated by a localized backpropagation algorithm until the desired approximation accuracy is attained. The effectiveness of the proposed network is demonstrated through computer simulations.
Human‐motion recognition via a fuzzy associative memory system
Authors: Ushida Hirohide , Yamaguchi Toru , Takagi Tomohiro
Published: July 2007

Human‐motion recognition techniques so far present several problems, such as difficult knowledge representation and poor robustness. With the aim of achieving recognition of human motion in a robust way by using knowledge representation that is easy to be understood, this paper proposes a method utilizing a fuzzy associative memory system.

In the proposed method, the fuzzy associative memory system embodies fuzzy inference rules which define motion patterns of characteristic states contained in the time‐series pattern representing the motion. In the fuzzy associative memory system, inference is carried out with state transition patterns as input, and motion recognition is performed.

The inference in the fuzzy associative memory system has the following two characteristics: (1) since knowledge can be represented as inference rules, it is easy to be understood by humans; (2) even in ambiguous situations or when part of the input information is missing, the information can be restored, or the degree of ambiguity can be controlled at inference time, etc., by the bidirectional processing of the conditional and action parts of the rules, so that appropriate inference results are obtained.

In the proposed method, the time‐series motion patterns are converted into state transition patterns, and by using an associative inference system with the aforementionedcharacteristics, it is possible to perform robust recognition. The effectiveness of the proposed method is demonstrated through on‐line experimental results for the motion of nonspecific individuals.
Fast and accurate image generation with adaptive tables
Authors: Tanaka Toshimitsu , Takahashi Tokiichiro
Published: July 2007

The authors previously proposed the reflection integration method which generates a realistic image of objects, and the precise rendering method which accurately eliminates aliasing of images. The two methods have a common process which precisely integrates reflected lights over a unit sphere. Since this process involves a large amount of computation, accelerating the process is desired.

The present paper proposes a procedure which significantly reduces the computation without sacrificing its accuracy by using an adaptive sampling table. For a part on an object where a light is sharply reflected, the reflected light sharply reduces depending on directions. The proposed procedure uses the table which nonlinearly subdivides reflection direction; precisely where a reflected light changes sharply and roughly at rest. As a result, a full‐color image can be generated with a sufficient accuracy with 90 × 90 divisions in the table. This adaptive table reduces the computation time for the integration of reflection lights on a semisphere to one‐tenth the previous method, which is equivalent to the reduction of a total image generation time by 40 to 60 percent.
Analysis, generation and semantic representation in CONTRAST—a context‐based machine translation system
Authors: Isahara Hitoshi , Uchida Yuriko
Published: July 2007

This paper describes both a Japanese language analysis system and an English language generation system. The knowledge utilized by these systems has been incorporated into a context‐based machine translation system (CONTRAST) developed by the Electrotechnical Laboratory (ETL). The Japanese language analysis component of the CONTRAST system consists of individual modules to analyze syntax, semantics and context. The syntactic analysis module is a completely parallel parsing system based on Earley's algorithm. The semantic analysis module conducts analysis based on case relations. The contextual analysis module creates an intermediate representation that correspond to original text. It does this by placing events included in the semantic analysis results for each individual sentence within a framework that is read out from the general knowledge described as a process model in the concept dictionary. The English text generation system of CONTRAST begins with this intermediate representation. Then, referring to the concept dictionary (common with the analysis module), it creates English text according to generation rules created from the real life text data dependent knowledge relating to English newspaper articles. The format of the concept dictionary, which consists of descriptions of general knowledge, and the format of the intermediate representation, which is a description of the contextual information contained in each body of text, are the same. The outline of the conceptual system employed and studies on the process of creating this system are also discussed.
Spatio‐temporal anti‐aliasing by the pixel‐tracing method
Authors: Shinya Mikio
Published: July 2007

Anti‐aliasing is generally an expensive process because either super‐sampling or sophisticated rendering is required. This paper presents a new type of antialiasing filter, pixel tracing filter, for animation sequences, which does not require an additional sample or additional calculation in the rendering phase. The filter calculates the correlation among the images using animation information, and sub‐pixel information is extracted from the sequence based on the correlation. Theoretical studies prove that the filter becomes an ideal anti‐aliasing filter in the limit that the filter size is infinite. The algorithm is simple image processing implemented as post‐filtering. The computational cost is independent of the complexity of the scene. Experiments demonstrate the efficiency of the scene. Experiments demonstrate the efficiency of the filter. Almost complete anti‐aliasing was achieved at the rate of approximately 30 s per frame for very complex scenes at the resolution of 256 × 256 pixels. The pixel‐tracing filter provides effective anti‐aliasing for animation sequences at a very modest computational cost.
Handling of user interruption to achieve timing‐free utterances for spoken dialogue interface
Authors: Kikuchi Hideaki , Kudo Ikuo , Kobayashi Tetsunori , Shirai Katsuhiki
Published: July 2007

This paper considers the spoken dialogue interface, which is the basic system for the multimodal interface by speech, and discusses the handling of the interruption that ensures the user the timing‐free utterances. In the interruption by the user, if the utterance by the system is designed with the sentence as the unit, as in the conventional system, there will be produced a difference between the designed content of the utterance and the actually uttered content or the content received by the user. From such a viewpoint, the following method is proposed.

The unit for the utterance planning is defined as the information to be transmitted by a sentence, and which information is received is always monitored through the management of the turn‐taking between the speakers of the dialogue. As a result of experiment, the handling of smooth interruption is recognized in more than half the subjects. Using the proposed method, the difference between the utterance planned by the system and the utterance received by the user is reduced. It is verified also that the interface is made more convenient by the handling of the interruption. The time required for the user to complete the task is reduced by 7 percent, and the number of positive topic proposals is increased by 21 percent.
Segmentation of gray‐scale images using piecewise linear approximation
Authors: Yamasaki Issei , Ohshima Tohru , Hasegawa Makoto , Furukawa Takao
Published: July 2007

This paper deals with clock truncation coding for gray‐scale images. An image region is segmented into unequal‐sized square blocks according to local luminance variations and luminance values in the block are approximated by triangular plane patches constructed from the luminance values at the four vertices of the block. Computational complexities of the unequal‐sized block segmentations are discussed. Segmentations are classified into three types: top‐down splitting; bottom‐up merging; and generalized split‐and‐merge method. It is derived from the theoretical model that initial block size in the split‐and‐merge method for a given image of size 256 × 256 is 17 × 17. Segmentation by accumulated square error is preferred to human visual sensitivity. Experimental results using a standard image have clarified that the segmentation by the accumulated square error improves the quality of approximated image to 1 to 2 dB compared with segmentation by the mean square error. Moreover, it is confirmed that the approximation by triangular plane patches is superior to JPEG for the compression of the images that have much flat areas.
Adaptive routing technique on hypercrossbar network and its evaluation
Authors: Boku Taisuke , Nakazawa Kisaburo , Nakamura Hiroshi , Sone Takeshi , Mishima Takeshi , Itakura Ken'Ichi
Published: July 2007

This paper studies the hypercrossbar network which has high flexibility and extensibility as a massively parallel computer network. Its performance is evaluated in nonroutine processing by computer simulation and theoretical analysis. To improve its performance, an implementation method of adaptive routing based on dynamic path determination is proposed, and its performance is evaluated by computer simulation. It is verified that the hypercrossbar network with adaptive routing has about 45 percent of the peak throughput at random transfer. Furthermore, its effectiveness is extremely high for applications with hot‐spot. It can attain about 8 times throughput compared with fixed routing.
A disattenuated correlation estimate when variables are measured with error: Illustration estimating cross‐platform correlations
Authors: Archer K. J. , Dumur C. I. , Taylor G. S. , Chaplin M. D. , Guiseppi‐Elie A. , Buck G. A. , Grant G. , Ferreira‐Gonzalez A. , Garrett C. T.
Published: June 2007

Previous cross‐platform reproducibility studies have compared consistency of intensities as well as consistency of fold changes across different platforms using Pearson's correlation coefficient. In this study, we propose the use of measurement error models for estimating gene‐specific correlations. Additionally, gene‐specific reliability estimates are shown to be useful in prioritizing clones for sequence verification rather than selecting clones using a simple random sample. The proposed ‘disattenuated’ correlation may prove useful in a wide variety of studies when both X and Y are measured with error, such as in confirmation studies of microarray gene expression values, wherein more reliable laboratory assays such as real‐time polymerase chain reaction are used. Copyright © 2007 John Wiley & Sons, Ltd.
SPS – ein neues Verfahren zur Instandsetzung und Ertüchtigung von stählernen orthotropen Fahrbahnplatten
Authors: Minten Joachim , Sedlacek Gerhard , Paschen Michael , Feldmann Markus , Geßler Achim
Published: June 2007

Dieser Beitrag beschreibt die Planung und wissenschaftliche Unterstützung der Erstanwendung der SPS‐Auflegetechnik zur Ertüchtigung bestehender Stahlfahrbahnen von Straßenbrücken für die zukünftige Verstärkung des Verkehrs, um mögliche Ermüdungsschäden im Deckblechbereich und Schäden des Fahrbahnbelages abzuwenden.

Es wird die schrittweise Herangehensweise, nämlich Auswertung der positiven Erfahrungen mit der Anwendung dieser Bauweise im Schiffbau, Voranwendungen bei der kleinen und großen Fahrbahnplatte des zerlegbaren Brückensystems D‐Brücke, die Anwendung bei der Ertüchtigung der Stahlfahrbahn einer alten U‐Bahn‐Brücke in Berlin und schließlich die Pilotanwendung bei der Schönwasserparkbrücke in der BAB A 57 bei Krefeld dargestellt.

Bei dieser Pilotanwendung ging es besonders darum,

–·die Anwendung unter Baustellenbedingungen

–·eine schnelle Durchführung zur Reduzierung von Verkehrsstörungen

–·die Anwendbarkeit in Verbindung mit dem Gussasphalteinbau mit Einbautemperaturen von 225 °C ohne Schädigung des Elastomerkerns

nachzuweisen.

Der Beitrag geht auf die Untersuchungen für die Erteilung der Zustimmung im Einzelfall und die damit bewirkte Weiterentwicklung der SPS‐Technologie ein und zeigt, dass diese für die Ertüchtigung hervorragend geeignet ist.
Orthotrope Fahrbahnplatte – Entwicklungen und Möglichkeiten für die Zukunft
Authors: Wolchuk Roman
Published: June 2007

Brücken mit orthotropen Fahrbahnplatten sind in den 1950er Jahren zum ersten Mal in Deutschland gebaut und danach in vielen anderen Ländern eingeführt worden. Derzeit gibt es weltweit mehrere tausend Brücken mit orthotropen Platten. Die Dauerhaftigkeit dieser Brücken erwies sich als gut – mit Ausnahme einiger Plattenausbildungen, die in den 1960er und 1970er Jahren ausgeführt wurden, bei denen Ermüdungsprobleme infolge ungeeigneter Detailgestaltung und Fertigungsmängel aufgetreten sind. Der vorliegende Beitrag geht auf derartige Schäden ein.

Weiterhin wird auf die Entwicklung von Berechnungsmethoden eingegangen. Für den Entwurf werden einfache Modelle wie das vonPelikan‐Esslingerbenutzt. Der klassische Ermüdungsnachweis nachWöhlerist nur beschränkt gültig. Daher beruhen die derzeitigen Bemessungsvorschriften für orthotrope Platten mehr auf konstruktiven Empfehlungen aufgrund bewährter Bauarten.

Wegen ihres geringen Gewichts, ihrer Dauerhaftigkeit und ihrer Reserven für Lasterhöhungen versprechen orthotrope Fahrbahnplatten auch in Zukunft gute Einsatzmöglichkeiten, z. B. bei Brücken großer Spannweiten. Da sie leicht in bestehende Brücken mittragend integriert werden können, sind sie auch bestens geeignet, Betonfahrbahnplatten zu ersetzen. In den USA werden zur Zeit 40% der Straßenbrücken als “baulich ungenügend” und “funktionell nicht mehr ausreichend” eingestuft, wobei 2/3 der Beurteilung “ungenügend” auf Schäden der Betonfahrbahnplatten zurückzuführen sind. Mehrere größere Brücken erhielten in letzter Zeit neue Fahrbahnen in Form orthotroper Platten. Auf die Lösung der damit verbundenen Probleme wird eingegangen.
Volatile compounds of oxidized pork phospholipids
Authors: Meynier Anne , Genot Claude , Gandemer Gilles
Published: June 2007

Volatile compounds from oxidized pork muscle phospholipids (PL) were analyzed by a purge‐and‐trap method. Total volatile compounds were highly correlated with thiobarbituric acid‐reactive substances, mainly as a consequence of alkanals. Major compounds of the 32 identified substances were alkanals (6023 ng nonane equivalents/mg PL), followed by 2‐alkenals (514 ng nonane eq/mg PL) and 2,4‐alkadienals (368 ng nonane eq/mg PL). Hexanal (4850 ng nonane eq/mg PL) was the major compound from the oxidation of n‐6 fatty acids (mainly linoleic and arachidonic acid). Volatile compounds from the oxidation of n‐3 fatty acids were only minor and included 2,4‐heptadienal (45 ng nonane eq/mg PL) and 2‐pentenal and 2‐hexenal (49 ng nonane eq/mg PL). Finally, nonanal, a degradation compound from oleic acid, was present at a low level (200 ng nonane eq/mg PL) and remained constant during oxidation, which confirmed that monounsaturated fatty acids were stable toward metal‐catalyzed oxidation. With the exception of ester compounds, identified volatiles were qualitatively similar to those obtained in simpler systems, such as fatty acids or vegetable oils. Quantitatively, the volatile compound composition reflected the fatty acid composition of PL.
Heat‐induced gelation of rapeseed proteins: Effect of protein interaction and acetylation
Authors: Schwenke Klaus Dieter , Dahme Andreas , Wolter Thomas
Published: June 2007

The gel‐forming abilities of a rapeseed protein isolate, composed of 70% globulin (cruciferin) and 30% albumin (napin), and their individual protein components, were investigated. The influence of acetylation upon the gelation properties was also studied. Highest gel strength (measured as shear modulus) of the isolate was obtained at pH values around 9, which is between the isoelectric points of both major proteins. Purified cruciferin gave the highest shear modulus values, with maxima at pH 6 and 8. Weak and poorly stable gels exhibiting strong hysteresis were obtained with isolated napin. Acetylation resulted in a pH shift of the shear modulus maximum of the protein isolate to about 6. The gelation temperature of the acetylated isolate had the highest pH and concentration dependence compared with the other proteins.
Long‐Acting and Permanent Contraception: An International Development, Service Delivery Perspective
Authors: Jacobstein Roy
Published: June 2007

Recent scientific findings about long‐acting and permanent methods of contraception underscore their safety, effectiveness, and wide eligibility for individuals who desire them. This has led to new guidance from the World Health Organization to inform national policies, guidelines, and standards for service delivery. Although developing countries have made much progress in expanding the availability and use of family planning services, the need for effective contraception in general (and long‐acting and permanent methods in particular) is large and growing because the largest cohorts in human history are entering their reproductive years. More than half a billion people will use contraception in developing countries (excluding China) by 2015, an increase of 200 million over levels of use in 2000. The health, development, and equity rationales that historically have underpinned and energized the international family planning effort remain valid and relevant today. Despite the other compelling challenges faced by the international health community, the need to make family planning services more widely available is pressing and should remain a priority.
An ethnic dating of Beowulf
Authors: Davis Craig R.
Published: June 2007

An interest in Danish legend first appears at the West Saxon court in the 890s when King Alfred traced his father's lineage to Scyld. Alfred traced his mother's ancestry through the Jutish kings of Wight to Goths and Geats, suggesting a motive for the particular view of the ethnic past we find in Beowulf, especially the friendship the poet constructs between a Geatish ætheling and a Danish monarch. A modification of Michael Lapidge's paleographical dating of the archetype of Beowulf (2000) indicates a West Saxon exemplar before c. 900, confirming the mature king's court as a plausible context for Beowulf's composition.
Upper mantle structure beneath the Arabian Peninsula and northern Red Sea from teleseismic body wave tomography: Implications for the origin of Cenozoic uplift and volcanism in the Arabian Shield
Authors: Park Yongcheol , Nyblade Andrew A. , Rodgers Arthur J. , Al‐Amri Abdullah
Published: June 2007

Upper mantle structure between 150 and 400 km depth is imaged beneath the Arabian Shield and northern Red Sea by modeling P and S traveltime residuals from teleseismic events recorded on the Saudi Arabia National Digital Seismic Network, the 1995–1997 Saudi Arabian PASSCAL experiment, and three permanent stations (RAYN, EIL, and MRNI). Relative traveltime residuals were obtained using a multichannel cross‐correlation method and inverted for upper mantle structure using VanDecar's inversion method. The resulting images reveal a low‐velocity region (∼1.5% for the P model and ∼3% for the S model) trending NW–SE along the western side of the Arabian Shield and broadening to the northeast beneath the Makkah‐Madinah‐Nafud volcanic line. We attribute the low velocities to a mantle thermal anomaly that could be as large as 330 K and that is associated with the Cenozoic uplift of and volcanic centers on the Shield. Our tomographic images are not consistent with models invoking separate mantle upwellings beneath the northern and southern regions of the Shield and instead favor single plume or superplume models. We also find little evidence for low velocities beneath the northern Red Sea, suggesting that there might not be a geodynamic link between rifting in the Red Sea and plateau uplift and volcanism in the Shield.
Observations of wave orbital scale ripples and a nonequilibrium time‐dependent model
Authors: Traykovski Peter
Published: June 2007

Measurements of seafloor ripples under wave‐dominated conditions from the LEO15 site and the Martha’s Vineyard coastal observatory were used to develop a time‐dependent model for ripple geometry. The measurements consisted of backscatter imagery from rotary side‐scan sonars, centimeter resolution bathymetric maps from a two‐axis rotary pencil‐beam sonar, and forcing hydrodynamics. During moderate energy conditions the ripple wavelength typically scaled with wave orbital diameter. In more energetic conditions the ripples reached a maximum wavelength of 0.8 to 1.2 m and did not continue to increase in wavelength or decrease in height. The observations showed that the relict ripples left after storms typically had wavelengths close to the maximum wavelength. The time‐dependent model is based on an equilibrium model that allows the ripples to maintain wavelength proportional to wave orbital diameter until a suspension threshold determined by wave velocity and grain size is reached. The time‐dependent model allows the ripple spectra to follow the equilibrium solution with a temporal delay that is based on the ratio of the ripple cross‐sectional area to the sediment transport rate. The data was compared to the equilibrium model, a simplified version of the time‐dependent model (where the ripples were assumed to follow the equilibrium model only when the bed stress was sufficient to move sediment), and the complete time‐dependent model. It was found that only the complete time‐dependent model was able to correctly predict the long wavelength relict ripples and that the other approaches underpredicted relict ripple wavelengths.
Spatial variability in dissolved organic matter and inorganic nitrogen concentrations in a semiarid stream, San Pedro River, Arizona
Authors: Brooks Paul D. , Lemon Michelle M.
Published: June 2007

We performed synoptic sampling of a 95‐km reach of the San Pedro River, Arizona, to identify the effects of regional hydrology and land use on dissolved carbon and nitrogen concentrations. Six synoptic surveys, two before, two during, and two after the 2002 monsoon season, encompassed periods of both low and high stream discharge. Chloride concentrations and δ18O values during low‐flow periods indicated the river was divided into three hydrologically distinct reaches each roughly 30 km long. Upper and lower reaches were characterized by areas of localized groundwater input followed by downstream evapo‐concentration gradients, limited downstream solute transport, and highly variable carbon and nitrogen concentrations. In contrast, the middle reach was characterized by widespread groundwater input, continuous downstream hydrologic connectivity, and less variable carbon and nitrogen concentrations. During the monsoon season, base flow discharge increased five‐ to ten‐fold, dissolved organic matter and inorganic N increased two‐ to ten‐fold, Fluorescence Index (FI) values indicated a large input of terrestrial solutes, and both chloride concentrations and δ18O values indicated that stream water and alluvial groundwater were well mixed along the entire 95 km reach. Concurrently, the middle reach that exhibited continuous hydrologic connectivity during the nonmonsoon season was a net sink for N, while the reaches characterized by limited hydrologic connectivity during the low‐flow season exhibited net N export. Our data suggest that instream biogeochemical cycling during the monsoon season is influenced by antecedent conditions, specifically hydrologic connectivity, during the dry season.
Phospholipase C-γ1 is required for the activation of store-operated Ca2+ channels in liver cells
Authors: Litjens Tom , Nguyen Than , Castro Joel , Aromataris Edoardo C. , Jones Lynette , Barritt Greg J. , Rychkov Grigori Y.
Published: June 2007

Repetitive hormone-induced changes in concentration of free cytoplasmic Ca2+ in hepatocytes require Ca2+ entry through receptor-activated Ca2+ channels and SOCs (store-operated Ca2+ channels). SOCs are activated by a decrease in Ca2+ concentration in the intracellular Ca2+ stores, but the molecular components and mechanisms are not well understood. Some studies with other cell types suggest that PLC-γ (phospholipase C-γ) is involved in the activation of receptor-activated Ca2+ channels and/or SOCs, independently of PLC-γ-mediated generation of IP3 (inositol 1,4,5-trisphosphate). The nature of the Ca2+ channels regulated by PLC-γ has not been defined clearly. The aim of the present study was to determine if PLC-γ is required for the activation of SOCs in liver cells. Transfection of H4IIE cells derived from rat hepatocytes with siRNA (short interfering RNA) targeted to PLC-γ1 caused a reduction (by approx. 70%) in the PLC-γ1 protein expression, with maximal effect at 72–96 h. This was associated with a decrease (by approx. 60%) in the amplitude of the ISOC (store-operated Ca2+ current) developed in response to intracellular perfusion with either IP3 or thapsigargin. Knockdown of STIM1 (stromal interaction molecule type 1) by siRNA also resulted in a significant reduction (approx. 80% at 72 h post-transfection) of the ISOC amplitude. Immunoprecipitation of PLC-γ1 and STIM1, however, suggested that under the experimental conditions these proteins do not interact with each other. It is concluded that the PLC-γ1 protein, independently of IP3 generation and STIM1, is required to couple endoplasmic reticulum Ca2+ release to the activation of SOCs in the plasma membrane of H4IIE liver cells.
The role and characterization of phospholipase A1 in mediating lysophosphatidylcholine synthesis in Trypanosoma brucei
Authors: Richmond Gregory S. , Smith Terry K.
Published: June 2007

Lysophospholipids are ubiquitous intermediates in a variety of metabolic and signalling pathways in eukaryotic cells. We have reported recently that lysoglycerophosphatidylcholine (lyso-GPCho) synthesis in the insect form of the ancient eukaryote Trypanosoma brucei is mediated by a novel phospholipase A1 (TbPLA1). In the present study, we show that despite equal levels of TbPLA1 gene expression in wild-type insect and bloodstream trypomastigotes, both TbPLA1 enzyme levels and lysoGPCho metabolites are approx. 3-fold higher in the bloodstream form. Both of these parasite stages synthesize identical molecular species of lysoGPCho. TbPLA1 null mutants in the bloodstream form of the parasite are viable, but are deficient in lysoGPCho synthesis, a defect that can be overcome by the expression of an ectopic copy of TbPLA1. The biochemical attributes of TbPLA1-mediated lysoGPCho synthesis were examined in vitro using recombinant TbPLA1. Although TbPLA1 possesses an active-site serine residue, it is insensitive to serine-modifying reagents, such as di-isopropyl fluorophosphate and PMSF, a characteristic shared by lipases that possess lid-sheltered catalytic triads. TbPLA1 does not require metal co-factors for activity, but it does require interfacial activation prior to catalysis. Results from size-exclusion chromatography and binding kinetics analysis revealed that TbPLA1 activation by Triton X-100/GPCho mixed micelle surfaces was not specific and did not require the pre-formation of a specific enzyme–substrate complex to achieve surface binding.
Structures and metal-ion-binding properties of the Ca2+-binding helix–loop–helix EF-hand motifs
Authors: Gifford Jessica L. , Walsh Michael P. , Vogel Hans J.
Published: June 2007

The ‘EF-hand’ Ca2+-binding motif plays an essential role in eukaryotic cellular signalling, and the proteins containing this motif constitute a large and functionally diverse family. The EF-hand is defined by its helix–loop–helix secondary structure as well as the ligands presented by the loop to bind the Ca2+ ion. The identity of these ligands is semi-conserved in the most common (the ‘canonical’) EF-hand; however, several non-canonical EF-hands exist that bind Ca2+ by a different co-ordination mechanism. EF-hands tend to occur in pairs, which form a discrete domain so that most family members have two, four or six EF-hands. This pairing also enables communication, and many EF-hands display positive co-operativity, thereby minimizing the Ca2+ signal required to reach protein saturation. The conformational effects of Ca2+ binding are varied, function-dependent and, in some cases, minimal, but can lead to the creation of a protein target interaction site or structure formation from a molten-globule apo state. EF-hand proteins exhibit various sensitivities to Ca2+, reflecting the intrinsic binding ability of the EF-hand as well as the degree of co-operativity in Ca2+ binding to paired EF-hands. Two additional factors can influence the ability of an EF-hand to bind Ca2+: selectivity over Mg2+ (a cation with very similar chemical properties to Ca2+ and with a cytoplasmic concentration several orders of magnitude higher) and interaction with a protein target. A structural approach is used in this review to examine the diversity of family members, and a biophysical perspective provides insight into the ability of the EF-hand motif to bind Ca2+ with a wide range of affinities.
Daily intake of 100 mg ascorbic acid as urinary tract infection prophylactic agent during pregnancy
Authors: OCHOA‐BRUST GONZALO JAVIER , FERNÁNDEZ ALMA ROSA , VILLANUEVA‐RUIZ GERSON JESÚS , VELASCO RAYMUNDO , TRUJILLO‐HERNÁNDEZ BENJAMÍN , VÁSQUEZ CLEMENTE
Published: July 2007

Objective. To evaluate the role a daily intake of 100 mg of ascorbic acid plays in urinary infection prophylaxis during pregnancy. Methods and materials. A single‐blind clinical trial was carried out on pregnant women randomly assigned to the following treatment groups — Group A: oral treatment with ferrous sulphate (200 mg per day), folic acid (5 mg per day) and ascorbic acid (100 mg per day) for 3 months, and Group B: oral treatment with ferrous sulphate (200 mg per day) and folic acid (5 mg per day) for 3 months. All patients were clinically evaluated, and a urine culture was carried out each month for a period of 3 months. The χ2 and odds ratio were used to compare effects with and without ascorbic acid, and statistical significance was considered at p<0.05. Results. Global frequency of urinary infections was 25%. The presence of urinary infections in Group A (12.7%) was significantly lower than in Group B (29.1%), (p = 0.03, OR = 0.35, CI 95% = 0.13–0.91). Conclusions. Daily intake of 100 mg of ascorbic acid played an important role in the reduction of urinary infections, improving the health level of the gestating women. We recommend additional vitamin C intake for pregnant women in populations which have a high incidence of bacteriuria and urinary infections.