A reconstruction algorithm of electrical impedance tomography with optimal configuration of the driven electrodes

A reconstruction algorithm for electrical impedance tomography (EIT) is presented. The least-squares (LS) method is applied and a formulation similar to that of the perturbation method is found. The main difference from perturbation lies with the sensitivity matrix, which here is replaced by the Jacobian matrix, defined in terms of the partial derivatives of every sensing electrode pair voltage difference with respect to every element's conductivity. The mutual position between the active electrodes is chosen to give optimum sensitivity. The results shown that the algorithm presented here has a better convergence and needs fewer iterations than the perturbation method.     

Effects of rind removal on physicochemical quality characteristics of fresh‐cut watermelon [Citrullus lanatus (Thunb) Matsum & Nakai] during cold storage

The impact of removing the rind from fresh‐cut watermelon slices was assessed on the quality of the product during storage at 4 °C for 9 days. Flesh lycopene declined from 55.4 to 47.9 mg kg^?1 f.w. and colour lightness (L*) increased from 43.2 to 45.8 after 2 days of storage. Initial heart and placental flesh firmness increased from 7.3 and 9.8 N, respectively, to 9.5 and 12.8 N after 9 days, but were unaffected by rind processing. Electrolyte leakage from placental tissue was unaffected by storage and rind. Rind presence limited juice run‐off by 47.2% and maintained mean total soluble sugar concentration in the slices at 86.0 mg mL^?1 as opposed to 76.8 mg mL^?1 in rind‐less slices. Change in the quality was most pronounced between 0 and 2 day of storage. Removing the rind accelerated senescence and off‐flavour production, while the presence of rind improved the overall storage stability of fresh‐cut watermelon slices.     

Data-Driven Multithreading Using Conventional Microprocessors

This paper describes the Data-Driven Multithreading (DDM) model and how it may be implemented using off-the-shelf microprocessors. Data-Driven Multithreading is a nonblocking multithreading execution model that tolerates internode latency by scheduling threads for execution based on data availability. Scheduling based on data availability can be used to exploit cache management policies that reduce significantly cache misses. Such policies include firing a thread for execution only if its data is already placed in the cache. We call this cache management policy the CacheFlow policy. The core of the DDM implementation presented is a memory mapped hardware module that is attached directly to the processor's bus. This module is responsible for thread scheduling and is known as the Thread Synchronization Unit (TSU). The evaluation of DDM was performed using simulation of the Data-Driven Network of Workstations ({rm{D}}^2{rm{NOW}}). {rm{D}}^2{rm{NOW}} is a DDM implementation built out of regular workstations augmented with the TSU. The simulation was performed for nine scientific applications, seven of which belong to the SPLASH-2 suite. The results show that DDM can tolerate well both the communication and synchronization latency. Overall, for 16 and 32-node {rm{D}}^2{rm{NOW}} machines the speedup observed was 14.4 and 26.0, respectively.     

A framework for predictive modeling of anatomical deformations

A framework for modeling and predicting anatomical deformations is presented, and tested on simulated images. Although a variety of deformations can be modeled in this framework, emphasis is placed on surgical planning, and particularly on modeling and predicting changes of anatomy between preoperative and intraoperative positions, as well as on deformations induced by tumor growth. Two methods are examined. The first is purely shape-based and utilizes the principal modes of co-variation between anatomy and deformation in order to statistically represent deformability. When a patient's anatomy is available, it is used in conjunction with the statistical model to predict the way in which the anatomy will/can deform. The second method is related, and it uses the statistical model in conjunction with a biomechanical model of anatomical deformation. It examines the principal modes of co-variation between shape and forces, with the latter driving the biomechanical model, and thus predicting deformation. Results are shown on simulated images, demonstrating that systematic deformations, such as those resulting from change in position or from tumor growth, can be estimated very well using these models. Estimation accuracy will depend on the application, and particularly on how systematic a deformation of interest is.     

A mode-matching technique for the study of circular and coaxialwaveguide discontinuities based on closed-form coupling integrals

A mode-matching scheme for the analysis of concentric circular and/or coaxial waveguide step discontinuities is proposed in this paper. An analytical evaluation of the involved coupling integrals for all possible discontinuities formed by any combination of a circular and a coaxial waveguide is performed. The originality mainly concerns the multimode excitation and scattering at a circular-to-coaxial waveguide step junction. Numerical results for a number of applications are compared against those of other techniques and/or measurements and are found to be in good agreement     

Prebiotic potential of barley derived β-glucan at low intake levels: A randomised,double-blinded,placebo-controlled clinical study

This randomised, double-blinded, placebo-controlled clinical study aimed to evaluate the in vivo prebiotic potential of barley β-glucan. Fifty-two healthy volunteers aged 39–70 years were randomly assigned to consume daily a cake containing 0.75 g of barley β-glucan or a placebo for 30 d. Stool samples were collected before, during and 2 weeks after the intervention for bacterial enumeration. Gastrointestinal side effects were recorded during the treatment period. In older subjects (?50 years old), barley β-glucan induced a strong bifidogenic effect and an increase of bifidobacteria into traceable range in cases of no detectable baseline levels. A concurrent significant increase in bacteroides was also observed in this age group. Ingestion of the experimental food resulted in no undesirable gastrointestinal side effects in older subjects. We concluded that the daily intake of a cake containing barley β-glucan is well-tolerated and demonstrated significant bifidogenic properties in older healthy volunteers consuming their usual diets.     

Wireless telemedicine systems: an overview

Rapid advances in information technology and telecommunications and, more specifically, wireless and mobile communications - and their convergence ("telematics") are leading to the emergence of a new type of information infrastructure that has the potential of supporting an array of advanced services for healthcare. The objective of this paper is to provide a snapshot of the applications of wireless telemedicine systems. A review of the spectrum of these applications and the potential benefits of these efforts is presented, followed by successful case studies in electronic patient record, emergency telemedicine, teleradiology, and home monitoring. It is anticipated that the progress carried out in these efforts and the potential benefits of emerging mobile technologies will trigger the development of more applications, thus enabling the offering of a better service to the citizen     

The geometrical theory for the input impedance of the isosceles orthogonal triangular microstrip patch antenna

Contents The geometrical optics model for a triangular 45°/45°/90° patch antenna is presented. The antenna is fed by a current probe, and the input impedance of the antenna is found by the emf method. Numerical as well as experimental results show the validity of the model.

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Die geometrische Theorie der Eingangsimpedanz einer dreieckförmigen (45°/45°/90°) Mikrostripantenne

Übersicht Für das Modell einer dreieckförmigen (45°/45°/90°) Mikrostripantenne mit Speisung über eine Stromsonde wird die Eingangsimpedanz der Antenne nach der EMK-Methode berechnet. Numerische und experimentelle Ergebnisse bestätigen die Brauchbarkeit des Modells.

     

The epidemic of gang-related homicides in Los Angeles County from 1979 through 1994

OBJECTIVE: To determine trends in gang homicides and the population at greatest risk for homicide by reviewing all gang-related homicides in Los Angeles County, California, from January 1979 to December 1994. DESIGN: Homicide files of the Los Angeles Police Department and the Los Angeles County Sheriff's Department from 1979 to 1994 involving violent street gang activity were reviewed. Gang files were reviewed for demographic data, weapons used, homicides by drive-by shootings, and times and geographic areas of occurrence. SETTING: Los Angeles County from January 1, 1979, to December 31, 1994. MAIN OUTCOME MEASURES: Age, race, and sex of gang-related homicide victims; frequency of weapon use; and the change in gang-related homicide rates during the study period. RESULTS: A total of 7288 gang-related homicides occurred in Los Angeles County from 1979 through 1994; 5541 of these homicides occurred in Los Angeles Police Department and Los Angeles County Sheriff's Department jurisdictions. During the study period, the proportion of all homicides that were gang related increased from 18.1% to 43.0% (P < .001). Of the 5541 gang-related homicide victims, 4580 (85.6%) were aged 15 to 34 years, 93.3% were African American or Hispanic, 5157 (93.2%) were male, 3559 (64.2%) were gang members, and 1408 (25.4%) occurred during drive-by shootings. Firearms were used in an increasing proportion of homicides, from 71.4% in 1979 to 94.5% in 1994. Homicides by semiautomatic handguns dramatically increased during the study period. Gang-related homicide rates for African-American males aged 15 to 19 years increased from 60.50 per 100,000 population per year in 1979 to 1981 to 192.41 per 100,000 population per year in 1989 to 1991. CONCLUSIONS: Gang-related homicides in Los Angeles County have reached epidemic proportions and are a major public health problem. To prevent gang violence, the root causes of violent street gang formation must be alleviated, the cycle of violent street gang involvement must be broken, and access to firearms must be limited.     

A 32-electrode data collection system for electrical impedancetomography

A 32-electrode data collection system for electrical impedance tomography (ETT) is presented. In this system, the demodulator is a multiplexed sample and hold (S&H) circuit followed by a voltage difference stage. This configuration provides high CMRR due to the low (almost DC) operating frequency of the signals the difference stage is required to process