Search

The impact of electromagnetic interference (EMI) from cellular base station (BS) antennas on implantable cardiac pacemakers is clarified in this article. The estimation of the impact is based on in vitro experiments that are conducted using simulated multicarrier and multicode signals, which are transmitted from actual BS antennas and dipole antennas as the radiation source of the BS antenna. Critical interference to the electric field strength is revealed with respect to the 800-MHz band second-generation and 2-GHz band third-generation cellular systems. The experimental results show two things. One is that the pacemaker EMI depends on the average power of the transmission signals and does not depend on the peak-to-average power ratios of the transmission signals, which increase with the number of multicarriers and multicodes. The other is that the boundary of the EMI area where malfunctions occur closely approximates the contour of a 25-V/m electric field that is exited from a commercially available collinear array antenna typically used in BSs. Furthermore, no pacemaker EMI is detected in the immediate vicinity under the BS antenna at an input power level for typical operation. Accordingly, it is clear that the pacemaker EMI should not pose a concern in residential environments.

We investigated the possible involvement of apoptosis in the increased germ-cell degeneration in undescended testes (UDT). Experimental unilateral cryptorchidism was induced in 21-day-old rats, and both testes were removed for in-situ TUNEL staining of apoptotic cells at 1, 3, 7, 10, and 14 days postoperation. A gradual increase in the incidence of apoptosis was seen at 21-28 days of age in the control testes, followed by a decrease thereafter. After 10 days postoperation, the weight of the UDT was significantly lower than that of the contralateral descended testis (CDT) and the controls. However, the weight of scrotal testes in each group was similar. UDTs demonstrated a markedly increased incidence of apoptosis. By 7 days postoperation, the percentage of seminiferous tubules containing apoptotic germ cells significantly increased in UDTs compared with that in CDTs and controls (P0.001). Moreover, there was a significant difference in the percentage of seminiferous tubules containing apoptotic germ cells between CDTs and controls (P0.01). In addition, an increased incidence of seminiferous tubules containing 8-10 and10 apoptotic germ cells from 7, 10, and 14 days postoperation in UDTs was detected. In-situ TUNEL analysis demonstrated spermatocytes to be the main type of germ cells affected in all groups. These findings suggest that spermatogenesis decreases not only in the UDT, but also in the CDT, and that the germ-cell degeneration in cryptorchidism took the form of apoptosis.

Department of Otorhinolaryngology, Johannes Gutenberg-University, Mainz, GermanyINTRODUCTION: Functional polymorphisms (SNPs) ofthe vascular endothelial growth factor (VEGF) are asso-ciated with the incidence of oral squamous cell carcinoma(OSCC). An impact of VEGF-SNPs on prognosis of OSCCpatients seems possible. Therefore, correlations betweenprognostic parameters of OSCC patients and five VEGF-SNPs were determined.MATERIALS AND METHODS: In a retrospective long-term study, in 113 OSCC patients that underwentcurative resections, five VEGF-SNPs ( 1154 G/A,+405 G/C, +936 C/T, 2578 C/A, and 460 C/T) wereanalyzed. Associations between SNPs and prognosis(incidence of local recurrent disease, second cancer,metastases, death, total disease-free survival) wereexamined.RESULTS: After a mean follow-up time of 57.6 months,32 patients had local recurrences; 15 patients had secondcancer, 15 patients metastases, and 23 patients died. Themean disease-free survival was 43.1 months. A significantincreased incidence of OSCC in smokers with the VEGF 2578 A/C and 460 C/T SNP was seen (eachP 2orN > 0) together with the 1154 A/Aallele had a significant worse survival and a worse disease-free survival (both P 2) could be confirmed(P = 0.002).DISCUSSION: Possible reciprocal interactions betweensmoking and VEGF-SNP function were observed. Multi-variate analysis confirmed the VEGF +405 G/G genotypeto be associated with poor survival in advanced OSCCs; afurther use of this haplotype as biomarker has to bediscussed.J Oral Pathol Med (2012)Keywords: advanced; long-term; oral squamous cell carcinoma;prognosis; single-nucleotide polymorphisms; smoking; VEGF

Efficient computational algorithms for the trajectory control of multiarm free-flying space robots are presented. The motion of the aircraft itself during manipulation is considered in order to obtain an accurate trajectory control. The generalized Jacobian of multiarm free-flying space robots is obtained efficiently by regarding the total multilink system as a composite system consisting of two links with a joint. The algorithm can be easily extended to any tree-structured multiarm robot with rotational as well as prismatic joints except for closed-loop structures. An efficient computational algorithm for the resolved acceleration control of the multiarm free-flying robots is also presented. The computational complexities are evaluated and compared to those of fixed-base manipulators. It is shown that the computational complexity for the generalized Jacobian is five times greater than that for fixed-base manipulators whereas the resolved acceleration control requires twice the computation for fixed-base manipulators. >

We have developed an automatic method that efficiently detects the defect signatures of substrates and identifies possible problems pertaining to LSI/TFT-LCD manufacturing processes and tools. This system, which has no built-in libraries, can be applied to the mass production line of thin film devices. This method is useful to quickly detect problems that have been overlooked thus far.

Recently, solar energy generation and wind power generation have been introduced to electric power system. But, as for this natural energy, influence such as frequency fluctuation is exerted on electric power system, which is a fundamental problem in operation of a small grid system such as micro-grid. These systems should provide appropriate power quality compared to a large grid. However, using the telecommunication line for monitoring and controlling the system devices is costly, as an alternative method, autonomous distribution control which enables local power supply and demand control is also required in design and operational stage. This paper discusses benefits of these methods conducting cost evaluation.

In the recent years, the using of renewable energy power generation method is increasing. For power system stability in installation of renewable energy power generation, the mitigation of influence is very important. A micro-grid is a network system that attempts the coexistence of utility grid and distributed generation. The micro-grid should take a connection system form that adjusts to the area. This paper discusses different interconnections of micro-grid and the interconnection stability. The evaluation models in the micro-grid stability are tie line power flow and frequency deviation.

Recently, solar energy generation and wind power generation have been introduced to electric power system. But, as for this natural energy, influence such as frequency fluctuation is exerted on electric power system, which is a fundamental problem in operation of a small grid system such as micro-grid. These systems should provide appropriate power quality compared to a large grid. However, using the telecommunication line for monitoring and controlling the system devices is costly, as an alternative method, autonomous distribution control that enables local power supply and demand control is also required in design and operational stage. This paper discusses benefits of these methods conducting cost evaluation.

Modern filter systems allow a significant reduction of diesel particulate emissions. The new silicon bonded silicon carbide particulate filters (Si-SiC filters) play an important role in this application, because they provide flexibility in terms of mean pore size and porosity and also have a high thermal shock capability to meet both engineering targets and emission limits for 2005 and beyond. Particulate filters are exposed to high temperatures and a harsh chemical environment in the exhaust gas of diesel vehicles. This paper will present further durability evaluation results of the new Si bonded SiC particulate filters which have been collected in engine bench tests and vehicle durability runs. The Si-SiC filters passed both 100 and 200 regeneration cycles under severe ageing conditions and without any problems. The used filters were subjected to a variety of analytical tests. The back pressure and ash distribution were determined. The filter material was also analysed. In addition vehicle ageing was performed using the European driving cycle. A detailed description of the regeneration conditions and the results from analysis of the used filter will be presented. This investigation proved the high durability performance of the newly developed Si bonded SiC materials. Si bonded SiC filters are making debut on the market in both fuel additive and catalytic soot filter systems.

This paper reviews the in-vitro experiments made to estimate the impact of the EMI from cellular phones on implantable cardiac pacemakers in Japan. The approach of the EMI test system is to directly expose the pacemaker to the near- and far-fields generated by a dipole antenna and/or an actual cellular phone. The results were used by the electric medical equipment study group of Japan to establish guidelines for the use of current Japanese cellular phones. An actual test system of cellular base-station EMI with a pacemaker is presented. To simulate a realistic EMI situation, a torso phantom with an installed pacemaker is newly constructed A multi-carrier generator is used as the base-station RF signal source. A typical commercial base-station antenna is used to generate microwave EMF similar to that emitted from cellular base-stations. The results show that EMI impact is determined by the maximum averaged power, not the peak power, of the base-station RF signal.

We propose an automatic arrhythmia diagnosis system which can distinguish atrial rhythms from ventricular rhythms. This system discriminates the origination of cardiac stimulation by analyzing QRS complex beat by beat with Fourier analysis and neural network pattern recognition, and then diagnoses arrhythmia with measurement of heart-rate. As well as implementation into a conventional single-chip processor, capability for instantaneous diagnosis and applicability to implant devices are demonstrated.

We developed a system which detects life threatening ventricular arrhythmias with respect to each beat. In this paper, we applied the system to human intracardiac electrogram (EGM) data for demonstrating the clinical potential. The system analyzes Fourier spectrum of the EGM signal corresponding to an individual QRS complex, and classifies it to three kinds of rhythm origins using a neural network. In our study, supra-ventricular rhythms were classified from ventricle originated rhythms with high sensitivities and specificities.

The authors developed an arrhythmia diagnosis system which distinguishes supra-ventricular events from ventricular ones. The system uses a power spectrum of QRS complex to discriminate the origin of a rhythm, and then classifies 12 types of arrhythmias based on the heart-rate end its variations. The system was evaluated with human ECG data. Two kinds of origin, supra-ventricular and ventricular, were distinguished with more than 98% sensitivity and specificity. The discrimination was conducted with a simple processing of weighted summation of two power spectrum inputs (4 and 8 Hz). In arrhythmia classification, there were 14 misclassified beats among 2234 beats, but no clinically fatal errors were found.

High performance digital-analog mixed devices are fabricated on a high resistivity MCZ Si substrate with low oxygen in order to suppress substrate noise from digital to analog circuits. The low oxygen prevents substrate resistivity reduction due to thermal donor occurring during device fabrication process. Good characteristics of digital, analog and power amplifiers can be realized by optimizing the process of oxynitride, halo implantation and salicide. In 0.11 /spl mu/m CMOS, high drivability, that is, 770 /spl mu/A//spl mu/m for NMOS and 330 /spl mu/A//spl mu/m for PMOS was achieved at Ioff=10/sup -9/ A//spl mu/m. And fT value of 90 GHz for NMOS and 48 GHz for PMOS can be achieved. Additionally, high efficiency of 68% at 2 GHz operation can be realized in power amplifier with 0.30 /spl mu/m gate length.

The authors have developed a method to discriminate life-threatening ventricular arrhythmias by observing the QRS complex of the electrocardiogram (ECG) in each heartbeat. Changes in QRS complexes due to rhythm origination and conduction path were observed with the Fourier transform, and three kinds of rhythms were discriminated by a neural network. In this paper, the potential of the authors' method for clinical uses and real-time detection was examined using human surface ECGs and intracardiac electrograms (EGMs). The method achieved high sensitivity and specificity (>0.98) in discrimination of supraventricular rhythms from ventricular ones. The authors also present a hardware implementation of the algorithm on a commercial single-chip CPU.

A three-channel frequency-modulation telemetry system for the noninvasive measurement of cardiac output, rate of respiration, e.c.g. and basal transthoracic admittance of the unconstrained human subject is described. Tetrapolar admittance plethysmography has been employed to obtain the transthoracic admittance and its variations corresponding to the cardiac cycle and respiratory changes. Pulse duration modulation has been used in the transmitter system. The nonlinearity of the system is less than ±2·0%. The telemetry transmitter has a range of about 100 m, it weights approximately 200 g and is contained in a box measuring 150×100×50 mm. The batteries used provide a continuous life of 20 h. The system has been used to obtain data from normal subjects in different postures with breath hold and during normal respiration.

A portable thermomemory unit with a light, thin and flexible probe has been developed for the measurement of whole-day variations in deep body temperature. The probe consists of a thermistor, a heat-flow sensor and a heater. The probe detects heat flow from the skin; the heater then compensates for the heat lost and consequently the skin is effectively insulated from the ambient microenvironment. Skin temperature beneath the probe is therefore determined by the deep body temperature. The probe is 46 mm in diameter and 3 mm thick, its weight is 5 g. The probe is light and flexible and makes close contact with the skin. A 2 kbyte RAM in the unit enables up to 34 h of data to be collected with a sampling rate of once per minute. The device was applied to the chest and abdominal walls, and to the calf; the chest and abdominal deep body temperatures showed a significant dual phase diurnal variation, usually being low during sleep. In contrast, the calf showed a dynamic deep body temperature variation which depended on the amount of leg exercise. The device was found to be effective for analysing daily variations; measurements on the limbs suggested that it could be used for monitoring peripheral circulatory disorders.