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To resolve frequency ambiguity of tiered polyphase code (TPC), a differential encoding method to the secondary code of the TPC is proposed. By performing differential decoding, the frequency ambiguity is removed and the code sequence boundary is correctly found. In addition, the correlation results at the receiver can be used as a frequency offset estimator. Analysis on the receiver operations and the simulation results show that the proposed tiered differential-PC makes the code sequence boundary detection correctly under the frequency offset of up to several hundred hertz. The root mean squared error of the frequency offset estimation is reduced to

The RF community has long been searching for the ideal switch since the birth of electronics, and it is defined as a device having virtually no insertion loss (Ron = 0 Ω) over a wide frequency range, very high isolation [off-state capacitance (Coff)] = 0 fF), extremely high linearity (IIP2 and IIP3 → infinite), medium- to high-power handling (100 mW to 1 kW), and no dc power consumption. Our entire RF infrastructure ecosystem, from communication system networks, to satellite systems, to wideband spectral analysis, to instrumentation and radar systems, uses a variety of switches for signal routing and control (attenuation, phase shifting, etc.). The ideal switch was achieved long time ago using electromechanical relays, and even after nearly 100 years, it is still the best RF switch ever made from an electrical perspective [1]. It has very low insertion loss (Ron

The aim of this study was to isolate and characterize bacteriocin-producing bacteria from the intestine of duck to use as probiotics for livestock. A total of 416 strains were isolated from the small intestine and cecum of ducks and 13 isolates were finally selected after determinging inhibitory activity against pathogenic indicators by spot-on-lawn method. The selected strains were identified as Lactobacillus salivarius JWS 58, Lactobacillus plantarum JWS 1354, Pediococcus pentosaceus JWS 939, 7 strains of enterococci, and 3 strains of Escherichia coli. Lact. salivarius JWS 58, Ent. faecium JWS 833, and Ped. pentosaceus JWS 939 showed a strong inhibitory activity against Listeria monocytogenes. E. coli JWS 108 inhibited the growth of E. coli and Staphylococcus aureus. Lact. salivarius JWS 58 strain survived almost 50% in pH 2.5 phosphate buffer for 2 hr. Ped. pentosaceus JWS 939 and Lact. plantarum JWS 1354 showed strong amylolytic activity. These results suggest that a combination of bacteriocins or multispecies probiotics of the selected strains has a strong potential of alternative to antibiotics in livestock production. (Key words : Bacteriocin, Probiotics, Duck, Livestock, Antibiotics)

The aim of this study was to determine whether quantitative information obtained from [(18)F]fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) has a prognostic significance for patients with non-small cell lung cancer (NSCLC). We investigated (18)F-FDG PET imaging of 73 patients with NSCLC. The maximum standardized uptake value (SUV(max)) was significantly different between the histopathological types of tumour (squamous cell carcinoma (n=37, 12.4+/-5.1), adenocarcinoma (n=30, 8.2+/-5.8), bronchioloalveolar carcinoma (n=4, 2.6+/-1.7),0.01). In the univariate analysis of all patients, staging (P=0.0001), tumour cell type (P=0.013), and a SUV(max) greater than 7 (P=0.0011) was correlated with survival. However, a multivariate analysis identified staging and SUV(max) greater than 7 were affected survival adversely. The mortality rate of patients with group I disease (stage I to stage IIIA) was 5.8 times lower than that of patients with group II disease (stage IIIB to stage IV). Patients with a high SUV(max) (or =7) had a 6.3 times higher mortality than those with a low SUV(max)(7). By multivariate analysis of patients with squamous cell carcinoma, only grouping affected survival (P=0.008, relative risk=4.3). In the case of adenocarcinoma, the SUV(max) (10) correlated exclusively with poorer survival (P=0.031, relative risk=11.152). (18)F-FDG uptake correlated with survival in NSCLC. Especially in adenocarcinomas, the SUV(max) was complementary to other known prognostic factors.

This study was performed to determine sequences of the mt DNA D-loop region, including and and to analysis sequence variation polymorphism in Korean cattle. The resulting sequencies were compared with previously published sequences for other cattle breeds(GenBank J01394). The PCR was used to amplify an 1142bp between nucleotides 15061 and 404 within the D-loop region of mt DNA using specific primers. Korean cattle showed 24 polymorphic sites by nucleotide substitutions and insertions of single base pairs. About 50% of polymorphic sites were found in positions 16042 to 16122 with the most variable region. Among these polymorphic sites, variations at 16055, 16230 and 16260 bp were detected as new sequence variants in Korean cattle. These specific polymorphic sites have not been reported in the Japanese black cattle and European cattle. Therefore, mt DNA variants in the D-loop region may be used as genetic markers for specifying Korean cattle. The frequencies of positions 169, 16302, 16093, 16042, 16119 with a high level of sequence polymorphism were 0.81, 0.56, 0.56, 0.50 and 0.43, respectively. In comparison of genetic distances, Korean cattle showed the more closely to European cattle as Bos taurus than Bos indicus such as African and India breeds. In conclusion, these mt DNA sequence polymorphisms in the D-loop region for Korean cattle may be useful for the analysis of cytoplasmic genetic variation and associations with economic important traits and genetic analysis of maternal lineage.

A particle detector for high flux applications has been fabricated based on highly oriented diamond (HOD) films. Relatively thick HOD films were achieved by combining the bias enhanced nucleation (BEN) in a microwave plasma chemical vapor deposition (MPCVD) reactor and high rate growth process in a low pressure combustion flame (LPCF) reactor. Following the diamond deposition, Si substrate was etched away to obtain a free standing, 4 mm diameter diamond membrane. A Ti/Au microstrip electrode pattern was applied to one side of the detector to provide spatial resolution. The detector performance was tested by measuring the energy spectra of α-particles emitted from an 241Am source. As compared to the performance of a polycrystalline diamond detector, the HOD detector showed a three to four fold improvement in performance, which was close to that obtained for single crystalline diamond detectors.

We demonstrate the use of near-field fiber-optic probes in optical heterodyne characterization of high-speed devices. The submicrometer-size optical beam obtained from the fiber-optic probe was employed to selectively excite a tiny area of the device active region. Optical heterodyne measurements on heterojunction bipolar transistors were conducted at 1.3 /spl mu/m with a difference frequency of 60 GHz. Significant response of the device with a signal-to-noise ratio of 25 dB was observed. The dc and ac photoresponse was also measured as a function of the distance between the fiber probe and the device-under-test. The data clearly showed distinguishable regimes of near- and far-field operation. The near-field high-frequency optical heterodyne technique as explored in this paper provides us with new capabilities that can be effectively utilized in the field of optical millimeter-wave interaction in ultrafast devices.

A multi-step process for the achievement of highly oriented, 〈100〉 textured diamond films on silicon using flat flame deposition has been developed. First, a bias-enhanced technique was used to achieve oriented nuclei on a Si 〈100〉 substrate in a microwave plasma reactor. Substrates were then transferred to the combustion system and rapidly grown into coalesced 〈100〉 films at a growth rate of 4–5 μm/h. X-ray texture analysis was used to characterize the films. It showed a 12 ° misalignment of the crystallites with respect to the surface normal, while the azimuthal misalignment was measured to be 20 °.

We demonstrate a novel technique for highly localized injection of millimeter waves in ultrafast devices that combines optical heterodyning and near-field optics. The technique relies on evanescent coupling of two interfering lasers to a submicron area of a device by means of a near-field fiber optic probe. Scanning measurements show the dc and ac photoresponses of two ultrafast device structures, namely low-temperature GaAs photoconductive switches and InP-based high electron mobility transistors. The response characteristics were rich in structures that revealed important details of device dynamics.

Effects of initial, intermediate and final sintering on superconducting properties, morphology, and critical current density, J/sub c/, were studied in Ag-sheathed Bi(Pb)-Sr-Ca-Cu-O tapes prepared using the powder-in-tube method and repetitions of a combined process of pressing and sintering. The variables in the repetitive process were a history by which the calcined constituent powders were heat treated before filled into Ag-tubes, and duration periods of the intermediate and final sinterings. The effects are discussed in terms of conversion of 2212 phase to 2223 and vice versa, the formation mechanism of 2223 phase, and alignment and connection of the 2223 grains. In the present study, a J/sub c/ on the order to 10/sup 4/ A/cm/sup 2/ at 77 K and 0 T was obtained. >

We demonstrate the use of near-field fiber-optic probes in optical heterodyne characterization of high-speed devices. The submicron-size optical beam obtained from the fiber-optic probe was employed to selectively excite a small local portion of the active region of the device. Optical heterodyne measurements on heterojunction bipolar transistors were conducted at 1550 nm with a difference frequency of 100 GHz. The significant response of the device with a signal-to-noise ratio of 30 dB was observed. The dc and the ac photoresponses were also measured as a function of the distance between the fiber-optic probe and the device under test. The data showed clearly distinguishable regimes of near- and far-field operation. The high-frequency near-field optical heterodyne technique as explored in this letter provides us with capabilities that can be effectively utilized in the field of optical millimeter-wave interaction in ultrafast devices.

Near field fiber optic probes have attracted a great deal of current interest mainly due to their ability to extend optical microscopy beyond the classical diffraction limit. Scanning optical microscopes using these probes have been yielded very high resolution in imaging and spectroscopic applications at visible and infrared wavelengths. The technology has been applied to imaging in biology, material science, surface chemistry and information storage. In this work, we explore a novel use of the near field fiber optic probes in optical heterodyne characterization of high speed devices. Because of the submicron feature size of modem electronic devices, conventional optical heterodyning only yields the response of the device as a whole. Introducing near field fiber optic probes allows one to examine spatially resolved details of device response and thereby provides a means to look more closely at the internal carrier dynamics. Our technique thus comprises an important tool for the experimental study of ultrafast devices.

This paper describes a parallel algorithm of an automated CMOS circuit extraction that transforms an IC layout into a circuit netlist suitable for circuit simulations. Using reconfigurable parallel machine architecture, the newly developed algorithm achieved a circuit extraction performance which is a constant time complexity. The layout of a CMOS inverter used successfully to demonstrate an efficiency of the newly developed algorithm.

Near-field optical heterodyning (NFOH) is a novel technique for the injection of millimeter waves at any arbitrary point of an ultrafast device or circuit with high degree of spatial localization. The technique has the capacity to provide details of the operation of the device being probed, which are inaccessible using conventional means. In essence, the technique involves optical mixing of two lasers in a tiny area of the device using near-field coupling. In this paper, we present the results of more comprehensive measurements, in which we performed a scan across the entire device under test. These results show first, the resolution capabilities of the NFOH technique and second, the kind of details one can obtain about the dynamics of ultrafast devices. Two new categories of devices, namely photoconductive switches and high electron mobility transistors (HEMTs), were tested to illustrate the versatility of the technique.

The sintering temperature significantly changed the microstructure and effected the power loss behavior at the frequency range over 100kHz. The best power loss characteristics at l00kHz-200mT and 500kHz-50mT were observed in the samples sintered at 1300°C and 1250°C, respectively. Those results indicated that the power loss depended on the grain size, electrical resistivity and density of sintered cores. To maintain the stoichiometry at the sintering condition, the ferrite cores were processed on the isocomposition lines within the spinel phase boundary when being cooled. The zinc vapor pressure as well as the oxygen partial pressure was controlled. The high zinc loss condition had an adverse effect on the microstructure of the sintered core surface and degraded the power loss characteristics.

Uniaxially-aligned powder composites of Y1Ba2(Cu1−xFex)3Oz for x ≤ 0.1 are formed by magnetic alignment of particles suspended in epoxy. The anisotropic lower critical field Hc1 was determined from a procedure based on the Bean's critical state model to pick up the onset of flux penetration in magnetization curves. For both field orientations H∥c and H∥ab at 4.2 K, Hc1 decrease linearly with increasing Fe content from Hc1 = 298 Oe to 32 Oe and from 101 Oe to 3 Oe, respectively. The temperature dependancies of Hc1 for both H∥c and H∥ab are such that it tends to decrease linearly with increasing temperature.

Background: Lung clearance of inhaled -DTPA reflects alveolar epithelial permeability and it had been reported as more sensitive than conventional pulmonary function tests in detecting lung epithelial damage. However, measuring lung clearance of inhaled -DTPA by gamma camera may not always reflect alveolar epithelial permeability exactly because it is influenced by mucociliary clearance depending on the site of particle deposition. Moreover, this method takes much time and patient's effort because he has to sit or lie still in front of the camera for a prolonged period. Most of the absorbed DTPA is excreted in urine within 24 hours and the amount of excreted DTPA in urine during the first few hours after inhalation is influenced by absorption rate which is correlated with the alveolar-epithelial permeability suggesting that the urinary excretion, especially in first few hours, may be an alternate index for lung clearance. The purpose of this study was to evaluate the usefulness of ratio of excreted -DTPA in 2 hour and 24 hour urine as an index of alveolar-epithelial damage. Methods: Pulmonary function tests including diffusing capacity and lung clearance of -DTPA measured by gama camera () and 2hr/24hr urine excretion ratio (Ratio) of inhaled -DTPA in 8 normal subjects and 14 patients with diffuse interstitial lung disease were compared. Results: 1) In the normal control, there was significant negative correlation between the and the Ratio (r=-0.77, p and Ratio(r=-0.63, p was min which was significantly lower than that of normal control, min and the Ratio was also signifantly higher than that of the normal control, (p or Ratio and diffusing capactiy of lung in both patients and controls (p>0.05). Conclusion: These results suggests that 2hr/24hr urine excretion ratio of inhaled -DTPA is a useful simple bedside test in assessing alveolar epithelial permeability and that it may be used as an additive follow-up test in patients with diffuse interstitial lung disease complementing conventional pulmonary function tests.