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Introduces a series of articles on nonthermal medical/biological treatments using electromagnetic fields and ionized gases.

In this paper, an atmospheric pressure low-temperature plasma pencil generated in helium and helium/oxygen gas mixtures was characterized in detail for its discharge characteristics, plasma power, reactive plasma species produced, plasma density, and plasma temperatures using electrical and optical emission spectroscopy (OES) diagnostics, and its efficacy for biomedical application. A visible plasma plume length of approximately 27 mm was generated using a 60-kHz ac HV power supply. The OES results showed the most intensive plasma emission lines of OH transition A^2\Sigma^+(v=0,1)\toX^2\Pi(\Delta\nu=0) at 308 nm and OH transition A^2\Sigma^+(v=0,1)\toX^2\Pi(\Delta\nu=1) at 287 nm, O I transition 3p^5P\to 3s^5S^0 at 777.41 nm, O I transition 3p^3P\to 3s^3S^0 at 844.6 nm, and N2(C\-B) second positive system with electronic transition C^3\Piu{\to}B^3\Pig in the range 300–450 nm. The effects of controlled oxygen content on the plasma pencil and on various helium plasma emissions and electrical properties are studied. A spatial distribution of reactive plasma species produced by the plasma pencil is presented. The electron density of plasma jet was estimated to be in the order of 2.1\times 10^14~cm^-3 using Stark broadening line profile of the hydrogen alpha emission. The temperatures of afterglow plasma pencil were evaluated using OH rotational temperatures, and the results demonstrate temperatures of 316 and 362 K for pure He and He/ O2 gas mixtures (0.1% O2 ), respectively. Preliminary results on inactivation of Streptococcus pneumoniae on a solid surface and in liquid suspension were carried out using the plasma pencil for biomedical applications. [ABSTRACT FROM PUBLISHER]

Biomedical industry is in continuous growth in the last few years. Low profile compact antennas are crucial in the development of wearable human biomedical systems. The polarization of the proposed antenna may be linear or dual polarized. Design considerations, computational results and measured results on the human body of several compact wideband microstrip antennas with high efficiency at 434~MHz\pm 5\% are presented in this paper. The compact dual polarized antenna dimensions are 5\,\times\,5\,\times\,0.05 cm. The antenna beam width is around 100^\circ. The antennas gain is around 0 to 2 dBi. The proposed antenna may be used in Medicare RF systems. The antennas S11 results for different belt thickness, shirt thickness and air spacing between the antennas and human body are presented in this paper. If the air spacing between the new dual polarized antenna and the human body is increased from 0 mm to 5 mm the antenna resonant frequency is shifted by 5%. [ABSTRACT FROM PUBLISHER]

The article outlines the most salient features of the journal "IEEE Transactions on Biomedical Engineering" (T-BME) during 2005. Also, the article addresses some important modifications that will add to the quality and scope of the journal. All T-BME issues in 2005 were printed in time. Moreover, there was a decrease in the paper backlog in 2005. It is expected that with the increase of the page budget for 2006, it should drop to a residual value at the end of the year. A new type of manuscript called T-BME Letters, the first of its kind in bioengineering will be started from the year 2006. Manuscripts submitted to T-BME under the category of letters will have a special treatment.

In this paper, an equivalent circuit model for nested split-ring resonators (NSRRs) is proposed. NSRRs are an emerging class of split ring resonators, preferred in a range of areas from sensing in biomedical or civil engineering applications to antenna design, due to their more compact size and enhanced sensitivity/resolution characteristics over the conventional SRRs. In the proposed model, the NSRR structure is treated as a combination of basic elements, i.e., strips and gaps, and the electromagnetic characteristics of the whole geometry are expressed in terms of capacitances and inductances of each of these elements. The outputs of the model are compared with those obtained via full-wave simulations using the package programs as well as measurements. The variation of NSRR resonance frequency ( f\text {res} ) with all important design parameters is also compared with full-wave simulations. In all comparisons, the results demonstrate agreement, showing that the proposed model can correctly explain the electromagnetics of the NSRR structure and that it provides an intuitive way for a better and easier analysis and a preliminary design of normally complex structures. [ABSTRACT FROM AUTHOR]

This paper presents a predictive framework for the statistical personalization of ventricular fibers. To this end, the relationship between subject-specific geometry of the left (LV) and right ventricles (RV) and fiber orientation is learned statistically from a training sample of ex vivo diffusion tensor imaging datasets. More specifically, the axes in the shape space which correlate most with the myocardial fiber orientations are extracted and used for prediction in new subjects. With this approach and unlike existing fiber models, inter-subject variability is taken into account to generate latent shape predictors that are statistically optimal to estimate fiber orientation at each individual myocardial location. The proposed predictive model was applied to the task of personalizing fibers in 10 canine subjects. The results indicate that the ventricular shapes are good predictors of fiber orientation, with an improvement of 11.4% in accuracy over the average fiber model. [ABSTRACT FROM AUTHOR]

Pulsed electric fields have recently been the focus of considerable attention because of their potential application in biomedicine. However, their practical clinical applications are limited by poor understanding of the interaction mechanism between pulsed electric fields and cells, particularly in the process of electroporation and its effect on parameter selection. This paper established a multishelled dielectric model based on finite elements to simulate and analyze the processes involved in electroporation. In particular, the processes include the dynamic development of the pore radius and electroporation region: the distribution of recoverable, nonrecoverable, and nonelectroporation areas on the cell; and the influence of pulse parameters on varying degrees of electroporation. Results showed that membrane conductivity, pore density, transmembrane potential, and distribution of pore radii are functions of time and position on the cell. The electroporation areas were divided into recoverable, nonrecoverable, and no-electroporation pores. For 10~\mu \texts , 1.5-kV/cm pulse was observed in the regions exposed to sufficiently high transmembrane voltage (1 V), electroporation occurred, membrane conductivity and pore density (up to 10^\mathrm 16/\textm^\mathrm 2) rapidly increased with time, and electroporation areas increased gradually and were mainly distributed in the range 0°–70° (recoverable pore [0°, 35°], nonrecoverable pore [35°, 70°], and no-electroporation pore [70°, 90°]). Electric field strength was the major factor that induced electroporation, particularly in the recoverable pore, but it had minimal effect on pore expansion. However, pulse duration affects the nonrecoverable pore, such that the high-intensity wide pulse is more useful in the field of irreversible electroporation. The high-intensity short pulse can increase permeability and maintain cell viability. [ABSTRACT FROM AUTHOR]

Can low-temperature plasma technology play a role in medicine? This is a question that many investigators today are trying hard to give a positive answer to. It did not quite start out this way. Almost two decades ago, few "curious" electrical engineers and physicists with the help of few "brave" biologists! microbiologists asked themselves more basic questions: What happens to biological cells if they were exposed to low-temperature plasma? Will they die? Will they survive? If they survive, will they come out the same or somehow "injured"? If injured, will they be able to repair the damage and recover? What kind of damage? Which plasma agent causes the damage? etc. As will be shown in this paper, some of these fundamental questions have been partially or fully answered, but until today, a complete picture has yet to emerge. This is good and not so good. It is good because if we already knew all the answers, we would not be looking forward to a more exciting research. It is not so good because after all these years, we are still quite a ways from an implementable medical application. In this review paper, the present state of knowledge regarding the effects of cold plasma on bacteria cells (prokaryotes) and on eukaryotic cells (such as mammalian cells) will be presented. As medical applications where low-temperature plasma is showing signs of success, blood coagulation and wound healing will be described. [ABSTRACT FROM AUTHOR]

We consider a generalized joint optimization policy of block replacement & periodic review spare inventory with random lead time. According to the relationship between geometric area in the graph of inventory level over time, and holding or shortage costs, a model analyzing four mutually exclusive & exhaustive possibilities is developed for the expected average cost per unit time, and is based on the stochastic behavior of the assumed system. The model reflects the cost of inventory holding, spare shortage, replacement, and ordering. And for the first time known to the authors, we deliver the sufficient and necessary conditions of the existence and uniqueness of the minimum in the joint models of this type. Because the model and its analysis are general, one existing result is shown to be subsumed by this model with some modifications. Some numerical cases verify the deduction, and give a general searching solution procedure. Finally, we introduce some discussions related to the models. The models mentioned in the paper can be readily applied in many fields such as economical fields, financial engineering, armament administration, and even medical fields, with some modifications. And the mathematical deduction in the paper will be a guideline for analyzing related stochastic models. [ABSTRACT FROM AUTHOR]

We present a study of image features for cancer diagnosis and Gleason grading of the histological images of prostate. In diagnosis, the tissue image is classified into the tumor and nontumor classes. In Gleason grading, which characterizes tumor aggressiveness, the image is classified as containing a low- or high-grade tumor. The image sets used in this paper consisted of 367 and 268 color images for the diagnosis and Gleason grading problems, respectively, and were captured from representative areas of hematoxylin and eosin-stained tissue retrieved from tissue microarray cores or whole sections. The primary contribution of this paper is to aggregate color, texture, and morphometric cues at the global and histological object levels for classification. Features representing different visual cues were combined in a supervised learning framework. We compared the performance of Gaussian, k-nearest neighbor, and support vector machine classifiers together with the sequential forward feature selection algorithm. On diagnosis, using a five-fold cross-validation estimate, an accuracy of 96.7% was obtained. On Gleason grading, the achieved accuracy of classification into low- and high-grade classes was 81.0%. [ABSTRACT FROM AUTHOR]

Time-series classification has attracted considerable research attention due to the various domains where time-series data are observed, ranging from medicine to econometrics. Traditionally, the focus of time-series classification has been on short time-series data composed of a few patterns exhibiting variabilities, while recently there have been attempts to focus on longer series composed of multiple local patrepeating with an arbitrary irregularity. The primary contribution of this paper relies on presenting a method which can detect local patterns in repetitive time-series via fitting local polynomial functions of a specified degree. We capture the repetitiveness degrees of time-series datasets via a new measure. Furthermore, our method approximates local polynomials in linear time and ensures an overall linear running time complexity. The coefficients of the polynomial functions are converted to symbolic words via equi-area discretizations of the coefficients’ distributions. The symbolic polynomial words enable the detection of similar local patterns by assigning the same word to similar polynomials. Moreover, a histogram of the frequencies of the words is constructed from each time-series’ bag of words. Each row of the histogram enables a new representation for the series and symbolizes the occurrence of local patterns and their frequencies. In an experimental comparison against state-of-the-art baselines on repetitive datasets, our method demonstrates significant improvements in terms of prediction accuracy. [ABSTRACT FROM AUTHOR]

The article discusses the increasing applications of ionized gases and electromagnetic fields in medicine and biology. Ionized gases are generated in open air at atmospheric pressure, or in a vacuum chamber. They find their applications in biological decontamination, pollution control, and sublethal modifications of cellular functions. Decontamination is required in health care and food manufacture. Electromagnetic fields are used in decontamination, and cell functions.

This paper summarizes the discussions held during the First IEEE Life Sciences Grand Challenges Conference, held on October 4–5, 2012, at the National Academy of Sciences, Washington, DC, and the grand challenges identified by the conference participants. Despite tremendous efforts to develop the knowledge and ability that are essential in addressing biomedical and health problems using engineering methodologies, the optimization of this approach toward engineering the life sciences and healthcare remains a grand challenge. The conference was aimed at high-level discussions by participants representing various sectors, including academia, government, and industry. Grand challenges were identified by the conference participants in five areas including engineering the brain and nervous system; engineering the cardiovascular system; engineering of cancer diagnostics, therapeutics, and prevention; translation of discoveries to clinical applications; and education and training. A number of these challenges are identified and summarized in this paper. [ABSTRACT FROM PUBLISHER]

Standard single-task kernel methods have recently been extended to the case of multitask learning in the context of regularization theory. There are experimental results, especially in biomedicine, showing the benefit of the multitask approach compared to the single-task one. However, a possible drawback is computational complexity. For instance, when regularization networks are used, complexity scales as the cube of the overall number of training data, which may be large when several tasks are involved. The aim of this paper is to derive an efficient computational scheme for an important class of multitask kernels. More precisely, a quadratic loss is assumed and each task consists of the sum of a common term and a task-specific one. Within a Bayesian setting, a recursive online algorithm is obtained, which updates both estimates and confidence intervals as new data become available. The algorithm is tested on two simulated problems and a real data set relative to xenobiotics administration in human patients. [ABSTRACT FROM AUTHOR]

Our analysis and measurements of a custom-designed two-port microstrip test fixture for biological tissue characterization at microwave and millimeter-wave frequencies demonstrated that the transmission parameter S21 would provide a better sensitivity to the complex permittivity change than the reflection coefficient S11. However, the standard through-reflect-line (TRL) calibration method employed for the extraction of the tissue complex permittivity did not fully remove the coaxial-to-microstrip adaptors' induced errors, which were manifested by ripple artifacts on the measured two-port S parameters. A simple deconvolution method was demonstrated wherein these errors were removed by postcalibration correction of the measured S21 of the tissue under test (TUT) by using water as a reference material. This paper provides a theoretical analysis of this method based on a model presented for postcalibration adaptors. Our detailed analysis shows that the error for S21 using the deconvolution method linearly depends on the difference between the S11 of the TUT and the reference material. Measurement and error estimation are also provided for various biological tissues and are consistent with analytical expectations. Our analysis provides support that systematic errors of numerically modeled S21 utilized for complex permittivity extraction can significantly be reduced by the deconvolution method. On the other hand, the analysis also shows that the S21 numerical modeling errors and the postcalibration adaptors' error terms have a similar impact on the extracted complex permittivity using the standard time-gating technique and are irreducible, unless the deconvolution method is used. Our analysis also identifies water as a better reference sample than methanol for accurate extraction of the complex permittivity of tissues in the range of ϵ' > 9 and ϵ" > 7 at 30 GHz. [ABSTRACT FROM AUTHOR]

In this paper, we present a sequential nonuniform procedure, an inference method which combines feature selection based on the Kullback information gain and a step-wise classification procedure to produce a reliable, interpretable, and robust model. We applied the model to an ovarian tumor data set to distinguish between malignant and benign tumors. The performance of the model was assessed using receiver operating characteristic (ROC) analysis and gave an overall accuracy over 85%, and area under the curve (AUC) of 0.887 which compares well with existing methods. The method presented here is significant because of its ability to handle missing values, and it only uses a small number of variables which are graded according to their discriminative relevance. This, together with the fact that the resulting model is interpretable and has good performance, is likely to lead to widespread clinical acceptance of the method. The method is also generic and can be readily adapted for other classifications problems in biomedicine. [ABSTRACT FROM AUTHOR]

Before undertaking new biomedical research, identifying concepts that have already been patented is essential. A traditional keyword-based search on patent databases may not be sufficient to retrieve all the relevant information, especially for the biomedical domain. This paper presents BioPatentMiner, a system that facilitates information retrieval and knowledge discovery from biomedical patents. The system first identifies biological terms and relations from the patents and then integrates the information from the patents with knowledge from biomedical ontologies to create a Semantic Web. Besides keyword search and queries linking the properties specified by one or more RDF triples, the system can discover semantic associations between the Web resources. The system also determines the importance of the resources to rank the results of a search and prevent information overload while determining the semantic associations. [ABSTRACT FROM AUTHOR]

Tongue diagnosis is an important diagnostic method in traditional Chinese medicine (TCM). However, due to its qualitative, subjective and experience-based nature, traditional tongue diagnosis has a very limited application in clinical medicine. Moreover, traditional tongue diagnosis is always concerned with the identification of syndromes rather than with the connection between tongue abnormal appearances and diseases. This is not well understood in Western medicine, thus greatly obstruct its wider use in the world. In this paper, we present a novel computerized tongue inspection method aiming to address these problems. First, two kinds of quantitative features, chromatic and textural measures, are extracted from tongue images by using popular digital image processing techniques. Then, Bayesian networks are employed to model the relationship between these quantitative features and diseases. The effectiveness of the method is tested on a group of 455 patients affected by 13 common diseases as well as other 70 healthy volunteers, and the diagnostic results predicted by the previously trained Bayesian network classifiers are reported. [ABSTRACT FROM AUTHOR]

Terahertz irradiation and sensing is being applied for the first lime to a wide range of fields outside the traditional niches of space science, molecular line spectroscopy, and plasma diagnostics. This paper surveys some of the terahertz measurements and applications of interest in the biological and medical sciences. [ABSTRACT FROM AUTHOR]

Since its inception more than a decade ago, Internet of Things (IoT) technology has been guiding people in the development of a world full of smart solutions in which all devices and physical objects, represented as “things,” are interlinked with sensors using the Internet. In some areas, the delivery of medications to patients or receivers at their destinations remains highly outdated and informal. In smart medicine delivery, the medicine needs to maintain its original state while facing multiple environmental factors, such as temperature fluctuations, humidity, etc. This paper presents an effective implementation of IoT (Internet of Things) for monitoring the transportation of medicines and vaccines, along with temperature control facilitated through mobile applications and sensor networks. The system employs mobile applications as the user interface, utilizes Arduino, MQTT (Message Queuing Telemetry Transport) for communication, incorporates a temperature sensor, and employs a mini portable cooling box. Designed for the generalized delivery of medicines/vaccines from sender to receiver, the system also suggests CRC-32 as an optimal algorithm for error detection instead of complex hash functions such as MD5 and SHA, ensuring better performance, smooth operation, and data integrity. In addition, elliptic curve-based shared keys are used for protected data transmission. The accuracy of the proposed system is 89.88%, and the value of the F1-score is 0.686, which is greater than the threshold of 0.5, hence conclusively validating the authenticity and reliability of the proposed system.

These instructions give guidelines for preparing papers for this publication. Presents information for authors publishing in this journal. [ABSTRACT FROM AUTHOR]

This paper presents a novel measurement technique for the broadband electromagnetic characterization of diluted suspensions of magnetic nanoparticles in aqueous solvents, the so-called water ferrofluids, which are of particular relevance for biomedical applications. The technique relies on the possibility of turning off the magnetic response of the suspended nanoparticles, without affecting the electric response of the ferrofluid, by applying a polarizing magnetostatic field of proper strength. In such a way, two different datasets are collected: 1) the on data (i.e., with the magnetostatic field applied), which only depend on the electric response of the investigated ferrofluid and 2) the off data (i.e., without the magnetostatic field applied), which depend on both the electric and magnetic responses of the ferrofluid. Therefore, the presented strategy enables the physical separation, at the measurement stage, of the electric response from the magnetic one, hence, a more reliable and accurate estimation of this latter, even in the case of strongly dielectric and weakly magnetic samples, as happens for diluted water ferrofluids. To implement the strategy a custom-made measurement cell has been designed and realized, by which an exhaustive measurement campaign, on a commercially available water ferrofluid, has been carried out. The obtained results show the effectiveness of the proposed strategy and its ability to estimate satisfactorily the magnetic response up to nanoparticle concentrations of a few milligrams per milliliter of solution, which are the concentrations of actual interest in biomedical applications. [ABSTRACT FROM PUBLISHER]

Biomedical nanomagnetics is a multidisciplinary area of research in science, engineering and medicine with broad applications in imaging, diagnostics and therapy. Recent developments offer exciting possibilities in personalized medicine provided a truly integrated approach, combining chemistry, materials science, physics, engineering, biology and medicine, is implemented. Emphasizing this perspective, here we address important issues for the rapid development of the field, i.e., magnetic behavior at the nanoscale with emphasis on the relaxation dynamics, synthesis and surface functionalization of nanoparticles and core-shell structures, biocompatibility and toxicity studies, biological constraints and opportunities, and in vivo and in vitro applications. Specifically, we discuss targeted drug delivery and triggered release, novel contrast agents for magnetic resonance imaging, cancer therapy using magnetic fluid hyperthermia, in vitro diagnostics and the emerging magnetic particle imaging technique, that is quantitative and sensitive enough to compete with established imaging methods. In addition, the physics of self-assembly, which is fundamental to both biology and the future development of nanoscience, is illustrated with magnetic nanoparticles. It is shown that various competing energies associated with self-assembly converge on the nanometer length scale and different assemblies can be tailored by varying particle size and size distribution. Throughout this paper, while we discuss our recent research in the broad context of the multidisciplinary literature, we hope to bridge the gap between related work in physics/chemistry/engineering and biology/medicine and, at the same time, present the essential concepts in the individual disciplines. This approach is essential as biomedical nanomagnetics moves into the next phase of innovative translational research with emphasis on development of quantitative in vivo imaging, targeted and triggered drug release, and image guided therapy including validation of delivery and therapy response. [ABSTRACT FROM AUTHOR]

One of the great challenges for understanding muscular diseases is to assess noninvasively the active and passive mechanical properties of the musculoskeletal system. In this paper we report the use of ultrafast ultrasound imaging to explore with a submillimeter resolution the behavior of the contracting tissues in vivo (biceps brachii). To image the contraction, which is a very brief phenomenon (<100 ms), a recently designed ultrasound scanner prototype able to take up to 6000 frames/s was used. A very high frame rate from 1000 to 2500 frames/s was used to image the cross section plane of the muscle (transverse to fibers) enabling us to catch in real time the muscle contraction during a transient electrostimulation. Tissue velocities were obtained from radio frequencybased speckle tracking techniques and their profiles arc discussed with respect to electrostimulation intensities and pulse repetition frequencies for different volunteers. Three-dimensional (3-D) very high frame rate movies were also acquired by repeating the experiment for different acquisition planes while triggering the imaging system with the electrostimulation device. The reconstructed 3-D velocity field allows the full localization of the contracting fibers bundle. This ultrasound technique, referred to as echo mechanomyography, offers new perspectives for in vivo and in situ noninvasive muscle diagnosis of an active contractile tissue. [ABSTRACT FROM AUTHOR]

The large-scale use of superconductivity continues to be dominated by applications for which there is generally no conventional option. In these cases, superconductivity has enabled new science and technology that could not exist without it. The fields of fusion energy and high-energy physics (HIEP) have particularly benefited from the application of superconductivity. High magnetic fields are absolutely necessary to achieve the required performance parameters. Even though superconductivity is an enabling technology for these fields, it comes with a number of challenges and market incursion has been very slow. However, thanks to persis- tent ongoing research, improvements in ancillary technology, and the development of new materials, the field is far from exhausted. On the contrary, many new applications in addition to high field magnets for scientific research and medical applications are on the horizon. Several applications are on the verge of accomplishing the much more difficult task of replacing existing conventional technology. This paper summarizes the current status of large-scale applications of superconductivity, using as an example magnet technology for fusion and HEP, and examines the prospects and challenges for new large-scale applications in the future. [ABSTRACT FROM AUTHOR]

The high complexity of cortical convolutions in humans is very challenging both for engineers to measure and compare it, and for biologists and physicians to understand it. In this paper, we propose a surface-based method for the quantification of cortical gyrification. Our method uses accurate 3-D cortical reconstruction and computes local measurements of gyrification at thousands of points over the whole cortical surface. The potential of our method to identify and localize precisely gyral abnormalities is illustrated by a clinical study on a group of children affected by 22q11 Deletion Syndrome, compared to control individuals. [ABSTRACT FROM AUTHOR]

This paper presents a robotic system for steering under real-time fluoroscopic guidance a flexible needle in soft tissue. Given a target and possible obstacle locations, the computer calculates the flexible needle-tip trajectory that avoids the obstacle and hits the target. Using an inverse kinematics algorithm, the needle base maneuvers required for a tip to follow this trajectory are calculated, enabling a robot to perform controlled needle insertion. Assuming small displacements, the flexible needle is modeled as a linear beam supported by virtual springs, where the stiffness coefficients of the springs can vary along the needle. Using this simplified model, the forward and inverse kinematics of the needle are solved analytically, enabling both path planning and path correction in real time. The needle shape is detected in real time from fluoroscopic images, and the controller commands the needle base motion that minimizes the needle tip error. This approach was verified experimentally using a robot to maneuver the base of a flexible needle inserted into a muscle tissue. Along the 40-mm trajectory that avoids the obstacle and hits the target, the error stayed below the 0.5-mm level. This study demonstrates the ability to perform closed-loop control and steering of a flexible needle by maneuvering the needle base so that its tip achieves a planned trajectory. [ABSTRACT FROM PUBLISHER]

The application of a medical guideline to the treatment of a patient's disease can be seen as the execution of tasks, sequentially or in parallel, in the face of patient data. It has been shown that many of such guidelines can be represented as a ‘network of tasks,’ that is, as a sequence of steps that have a specific function or goal. In this paper, a novel methodology for verifying the quality of such guidelines is introduced. To investigate the quality of such guidelines, we propose to include medical background knowledge to task networks and to formalize criteria for good medical practice that a guideline should comply with. This framework was successfully applied to a guideline dealing with the management of diabetes mellitus type 2 by using KIV. [ABSTRACT FROM AUTHOR]

This paper is aimed at demonstrating how the wavenumber domain analysis of two-dimensional (2-D) images captured by phase-sensitive laser probe systems is applied in the characterization of RF SAW devices. Effectiveness is demonstrated through the selective characterization of spurious resonance modes and scattered, nonguided modes appearing in SAW resonators. [ABSTRACT FROM AUTHOR]

Computer simulations are an essential tool for the design of phased-array ultrasonic imaging systems. FIELD II, which determines the two-way temporal response of a transducer at a point in space, is the current de facto standard for ultrasound simulation tools. However, the need often arises to obtain two-way spatial responses at a single point in time, a set of dimensions for which FIELD II is not well optimized. This paper describes an analytical approach for computing the two-way, far-field, spatial impulse response from rectangular transducer elements under arbitrary excitation. The described approach determines the response as the sum of polynomial functions, making computational implementation quite straightforward. The proposed algorithm, named DELFI, was implemented as a C routine under Matlab and results were compared to those obtained under similar conditions from the well-established FIELD II program. Under the specific conditions tested here, the proposed algorithm was approximately 142 times faster than FIELD II for computing spatial sensitivity functions with similar amounts of error. For temporal sensitivity functions with similar amounts of error, the proposed algorithm was about 1.7 times slower than FIELD II using rectangular elements and 19.2 times faster than FIELD II using triangular elements. DELFI is shown to be an attractive complement to FIELD II, especially when spatial responses are needed at a specific point in time. [ABSTRACT FROM AUTHOR]

This paper defines the echo signal-to-noise ratio (eSNR) for pulse-echo systems that adapts to the effects of shift-varying impulse responses, spatiotemporal coding, and various beamformers. Measurement techniques using point targets or random scattering media can he interrelated for a broad range of experimental conditions through the eSNR. The eSNR definitions are also illustrated by comparing a spatial matched filter (SMF) beamformer to conventional dynamic receive focusing methods to evaluate performance based on resolution and sensitivity. Closed-form expressions are presented that predict eSNR gains from SMF approaches relative to other beamformers. [ABSTRACT FROM AUTHOR]

This paper proposes an approach to designing binary codes suitable for high-frequency applications of coded excitation in medical ultrasound. For a high- frequency ultrasound system, transmitting well-designed binary codes with a low sampling ratio (i.e., the bit rate divided by the transducer center frequency) is a practical way to improve the signal-to-noise ratio (SNR) because the challenge of implementing arbitrary-waveform generators for transmitting nonbinary codes increases with the frequency and the switching speed of square-wave pulsers are limited. One conventional approach designs codes using a base sequence that modulates wideband sequences up to the transducer passband. Because a major portion of codes is excluded as a candidate, codes designed using this approach typically need long compression filters for restoring the axial resolution, and they do not improve the SNR efficiently. In contrast, the approach proposed here searches all the codes that match the transducer passband; hence, the resultant codes exhibit better performance. The technique was tested using a bit rate of 50 MHz and a sampling ratio of 2. For a transducer with an ideal Gaussian frequency response with a center frequency of 25 MHz and a -6 dB bandwidth of 15 MHz, the SNR for the same side-lobe extent was 1 to 6 dB higher for the codes designed using the proposed approach compared with those designed using the conventional approach. When a real transducer response with a center frequency of 26.4 MHz and a one- way -6 dB bandwidth of 20.7 MHz was considered, the codes designed using the proposed approach were superior by 0.5 to 5 dB. Therefore, our approach is better than the conventional approach for designing binary codes for high-frequency ultrasound, with the results indicating that the moderate bit rate of 50 MHz will suffice when the ultrasonic center frequency is 25 MHz. [ABSTRACT FROM AUTHOR]

This paper reviews the application of continuous recurrent neural networks with time-varying weights to pattern recognition tasks in medicine. A general learning algorithm based on Pontryagin's maximum principle is recapitulated, and possibilities of improving the generalization capabilities of these networks are given. The effectiveness of the methods is demonstrated by three different real-world examples taken from the fields of anesthesiology, orthopedics, and radiology. [ABSTRACT FROM AUTHOR]

Chemically ordered L10 phase FePt nanoparticles has been considered one of the best candidates for future magnetic recording media with areal density beyond 1 Tbit/in². However, current preparation methods via phase transformation must overcome many obstacles, including particle agglomeration, twinning and difficulty of easy axis alignment. In this paper, the direct preparation of L10 phase FePt nanoparticles without phase transformation and particles' aqueous phase self-assembly are reported. The mechanism for L10 phase formation during nucleation and growth processes are discussed. The unique octahedron shape makes these highly ordered FePt nanoparticles even better choice for advanced magnetic recording media because they tend to form tilted and patterned media simultaneously due to the shape effect. [ABSTRACT FROM AUTHOR]

Measuring intraocular pressure (IOP) has proved to be an important diagnosis tool for detecting and preventing glaucoma, a disease that could lead to blindness or even eye loss. Continuous lime monitoring of IOP is important for medical research. This paper evaluates the feasibility of two kinds of passive sensors to measure IOP and presents a complete measurement system for one of them. [ABSTRACT FROM AUTHOR]

A successful application of data mining to bioinformatics is protein classification. A number of techniques have been developed to classify proteins according to important features in their sequences, secondary structures, or three-dimensional structures. In this paper, we introduce a novel approach to protein classification based on significant patterns discovered on the surface of a protein. We define a notion called α-surface. We discuss the geometric properties of a-surface and present an algorithm that calculates the a-surface from a finite set of points in W. We apply the algorithm to extracting the a-surface of a protein and use a pattern discovery algorithm to discover frequently occurring patterns on the surfaces. The pattern discovery algorithm utilizes a new index structure called the ΔB+ tree. We use these patterns to classify the proteins. While most existing techniques focus on the binary classification problem, we apply our approach to classifying three families of proteins. Experimental results show the good performance of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper describes a project carried out in the lab- oratory of Principles of Bioengineering within the Telecommunications Engineering degree (five academic years plus a final thesis). The main object of this project is to set up a portable system for the acquisition, analysis, and transmission by mobile telephony of the electrocardiogram (ECG) of an indeterminate number of patients. The network of patients is managed from a control center (C C), comprising a personal computer (PC) with application software and a mobile telephony communications system. In a real system, each patient would have a patient terminal with a microprocessor- based, ECG-acquisition system with processing and transmission by mobile telephony. Time and technical considerations mean that, in the project, the patient terminal will have to be implemented in a PC. To perform this project, the students must have a wide range of knowledge acquired in this course and in other subjects required for this degree: design of bioamplifiers, information-processing algorithms, mobile-telephony communications, user-inter- face programming, etc. Having to use these concepts will no doubt serve as a stimulus to the students carrying out the work. [ABSTRACT FROM AUTHOR]

In this paper, we present a method of skin imaging called bidirectional imaging that captures significantly more properties of appearance than standard imaging. The observed structure of the skin's surface is greatly dependent on the angle of incident illumination and the angle of observation. Specific protocols to achieve bidirectional imaging are presented and used to create the Rutgers Skin Texture Database (clinical component). This image database is the first of its kind in the dermatology community. Skin images of several disorders under multiple controlled illumination and viewing directions are provided publicly for research and educational use. Using this skin texture database, we employ computational surface modeling to perform automated skin texture classification. The classification experiments demonstrate the usefulness of the modeling and measurement methods. [ABSTRACT FROM AUTHOR]

This paper provides a broad overview of medical robot systems used in surgery. After introducing basic concepts of computer-integrated surgery, surgical CAD/CAM, and surgical assistants, it discusses some of the major design issues particular to medical robots. It then illustrates these issues and the broader themes introduced earlier with examples of current surgical CAD/CAM and surgical assistant systems. Finally, it provides a brief synopsis of current research challenges and closes with a few thoughts on the research/industry/clinician teamwork that is essential for progress in the field. [ABSTRACT FROM AUTHOR]

With argon used as working gas, a laminar plasma plume with a fairly large volume is flushed out of a dielectricbarrier discharge device into the ambient air at atmospheric pressure. Discharge characteristics are investigated through electrical and optical methods. Results indicate that discharge power, based on Lissajous plot, increases with increasing the peak voltage. High-speed imaging indicates that the formation mechanism of the plasma plume corresponds to a series of microdischarge filaments leaving outlet of the gas duct, whose probable lifetime is about several milliseconds. [ABSTRACT FROM AUTHOR]