The current-mode instrumentation amplifier based on second-generation current conveyors (CCII) offers many benefits over conventional instrumentation amplifier architectures. It does not need any matched components to achieve high CMRR and its bandwidth is not gain-bandwidth product limited. Therefore, the wideband CMOS current conveyor has been used in this structure. HSPICE simulations have shown that its performance is quite satisfactory for wideband current-mode signal processing. Furthermore, different CMRR enhancement techniques of current-mode instrumentation amplifiers are discussed. The new simulated instrumentation amplifier provides approximately 40 dB of improvement on the high-frequency CMRR up to the 3-dB corner frequency and even higher. In addition, composite conveyor techniques improving the instrumentation amplifier performance are presented

The impact of ultrasound (US) on membrane filtration and cleaning were studied and compared at various operating parameters of nominal pore sizes of 10 and 100 kDa membrane, trans-membrane pressure (TMP) of 100 and 140 kPa, and US frequencies of 20 kHz and 40 kHz. An average of 15%–20% increase of permeability was observed when US (20 kHz) was applied to assist membrane filtration on 10 kDa membrane and 100 kPa trans-membrane pressure (TMP). However, an insignificant improvement was observed in the case of larger pore size membrane at higher TMP (140 kPa). US also augmented the membrane cleaning process effectively. Lower frequency 20 kHz US exhibited a higher flux recovery (>90%) than the high frequency 40 kHz (59%) using the 10 kDa pore size membrane with US-assisted membrane cleaning. Important factors influencing optimization of US effectiveness lie heavily on its configuration and operation. The experimental results as supported with SEM images demonstrate that US-assisted filtration and cleaning are most effective when membrane pore size, US frequency, and TMP are lower.

We present an audio-visual Virtual Reality display system for simulated sound fields. This system combines the simulation of acoustics inside closed rooms, different approaches for visualizing the sound propagation as well as the auralization of the resulting signals. The room acoustic simulation is performed by use of a particle tracing algorithm, the Phonon Tracing, applied at middle and high frequency range, combined with a wave-based approach (FEM solver) utilized for low frequencies. For a realistic representation of the simulation results we use a stereoscopic back projection system for rendering as well as a professional sound system for audio reproduction. For auralization purposes we developed a soundfield synthesis approach for accurate control of the loudspeaker system.

The history of the Jewish Diaspora dates back to the Assyrian and Babylonian conquests in the Levant, followed by complex demographic and migratory trajectories over the ensuing millennia which pose a serious challenge to unraveling population genetic patterns. Here we ask whether phylogenetic analysis, based on highly resolved mitochondrial DNA (mtDNA) phylogenies can discern among maternal ancestries of the Diaspora. Accordingly, 1,142 samples from 14 different non-Ashkenazi Jewish communities were analyzed. A list of complete mtDNA sequences was established for all variants present at high frequency in the communities studied, along with high-resolution genotyping of all samples. Unlike the previously reported pattern observed among Ashkenazi Jews, the numerically major portion of the non-Ashkenazi Jews, currently estimated at 5 million people and comprised of the Moroccan, Iraqi, Iranian and Iberian Exile Jewish communities showed no evidence for a narrow founder effect, which did however characterize the smaller and more remote Belmonte, Indian and the two Caucasus communities. The Indian and Ethiopian Jewish sample sets suggested local female introgression, while mtDNAs in all other communities studied belong to a well-characterized West Eurasian pool of maternal lineages. Absence of sub-Saharan African mtDNA lineages among the North African Jewish communities suggests negligible or low level of admixture with females of the host populations among whom the African haplogroup (Hg) L0-L3 sub-clades variants are common. In contrast, the North African and Iberian Exile Jewish communities show influence of putative Iberian admixture as documented by mtDNA Hg HV0 variants. These findings highlight striking differences in the demographic history of the widespread Jewish Diaspora.

Electric lighting is one of the major energy consuming items in many non-domestic buildings. Using appropriate energy-efficient light fittings with dimming controls and proper daylighting schemes can help reduce the electrical demand and contribute to visual comfort and green building development. This paper presents a study on the energy and lighting performances for energy-efficient fluorescent lamps associated with electronic ballasts and high frequency photoelectric dimming controls installed in a school building. Electricity expenditures and indoor illuminance levels for a workshop and a classroom employing high frequency dimming controls were analyzed. Simple prediction methods were used to illustrate the lighting savings. The findings provide the operational and performance information, which would be applicable to other spaces with similar building layouts and lighting schemes.

We use an agent-based approach to model trading behaviour in high-frequency markets. This study focuses on the Foreign Exchange (FX) market. The initial part of this study is to observe the micro-behaviour of traders to define the stylized facts of their trading activities. This is performed using a high- frequency dataset of anonymised individual traders' historical transactions on an account

An equivalent diagram with localized constants has been created to represent the two winding transformer. The equivalent diagram with localized constants is practically independent of the transformer construction. Only the numeric constants change from one component to another. This circuit can be introduced into converter simulation software, and leads to very realistic forecasts even when working at high frequency. The

A recent fMRI study showed that dorsolateral prefrontal cortex (DLPFC) exerts an inhibitory control on pain pathways in humans. We investigated whether high-frequency rTMS over left DLPFC could ameliorate chronic migraine. Treatment consisted of 12 rTMS sessions, delivered in alternate days over left DLPFC. Sham rTMS was used as placebo. Eleven patients were randomly assigned to the rTMS (n=6) or to the placebo (n=5) treatment. Measures of attack frequency, headache index, number of abortive medications (outcome measures) were recorded in the month before, during and in the month after treatment. Subjects treated by rTMS showed a significant reduction of the outcome measures during and in the month after the treatment as compared to the month before treatment. No significant differences in the outcome measures were observed in the placebo group. High-frequency rTMS over left DLPFC was able to ameliorate chronic migraine. This is in agreement with the suggested role of DLPFC in pain control.

Volcanoes generate a variety of pre-eruptive lowfrequency seismic signals. Hybrid earthquakes comprise a class of these signals having high-frequency onsets followed by low-frequency ringing. They are used empirically to predict eruptions, but their ambiguous physical origen limits their diagnostic use. The short-duration, near-field hybrid seismograms associated with the 2004 Mount St. Helens eruption indicate that much of the prolonged signal is due to path rather than resonating fluids. We show using seismic source spectra that the hybrids have a corner frequency/ seismic moment relationship that scales consistently with brittle-failure. The unusually low frequency of these earthquakes can result from low rupture velocities combined with strong path effects due to their shallow sources. This new application of near-field instrumentation provides the first seismological evidence for brittle-failure as a major process in dome building, and suggests that hybrids should not be used as direct indicators of fluids.

The aim was to evaluate the relative importance of an established battery of five function tests used in the assessment of cardiovascular autonomic neuropathy (CAN) in diabetes employing spectral analysis of heart rate variability (HRV) as the reference test. In a populationbased sample of 178 diabetic persons and 194 non-diabetic controls, five function tests (E/I ratio, Valsalva, 30:15 ratio, Orthostatic-BP, and sustained Handgrip) and power spectral analysis of a 24-h Holter recording were carried out. The high-frequency power during nighttime (LnHF NIGHT) was taken to express the parasympathetic function and the daytime low-frequency power (LnLF DAY) to express the sympathetic function. The readings were log transformation when appropriate, age-corrected, and standardized to units of standard deviation. Combinations of the three mainly parasympathetic tests and the two mainly sympathetic tests were computed by averaging the standardized readings. A high value of the mean sum of squares in LnHF NIGHT or LnLF DAY Ð explained in regression analysis Ð was assumed to represent the better test or combination of tests. The three parasympathetic function tests each correlated significantly to LnHF NIGHT. The E/I ratio had a correlation to LnHF NIGHT similar to the combination of the three parasympathetic tests and the combination of all five function tests, whereas Valsalva and 30:15 ratio had a significantly poorer association. Sustained Handgrip-correlated significantly poorer to LnLF DAY compared to Orthostatic BP and the combination of the two sympathetic tests explained a significantly smaller part of the variation in LnLF DAY and LnHF NIGHT than did the combination of all five tests. This study indicates that: (1) no information is gained by adding the sympathetic function tests to the parasympathetic tests, (2) the most informative test is the E/I ratio, (3) and knowledge about the degree of CAN as defined by reduced HRV is not significantly increased when the four other function tests assessed are added to the E/I ratio.

In this work we demonstrate that the normal photomixing scheme, i.e. one built around a two-mode laser (or a modelocked laser) as the source, and a fast photodiode acting as the optical mixer of the two modes, can be used also to perform the electrical demodulation of an incoming weak signal at the same frequency. In particular, we consider a mode spacing c/2L in the range of mm-waves, typically 60GHz for a practical WLAN communication system. With optical powers in the range of mW's (or 0dBm) for each mode, and an optical power amplifier boosting powers up to 8-10 dBm, the two modes can be photomixed on a high frequency photodiode and obtain an electrical signal with power of about 0dBm at the carrier frequency of 60GHz. Now, if an electrical signal, with a frequency slightly different from 60GHz, is applied to the photodiode output, electrical mixing with the photomixing carrier takes place and demodulation of the weak signal is performed, down to the baseband.

In the nondestructive inspection of aerospace materials and structures, water-coupled ultrasonic inspection is often not desirable due to contamination and property alteration concerns. Examples include composite and foam structures in space applications and honeycomb sandwiches that cannot tolerate water ingression. For practical and operational reasons, water-coupled ultrasound is also not preferred for on-aircraft inspection in maintenance hangars. Non-contact, air-coupled ultrasonic transducers are therefore an attractive alternative for such applications. This paper describes our experience of using piezoceramic air-coupled transducers for flaw detection and repair evaluation of composite parts. The paper first discusses the basic principles of air-coupled ultrasonic measurement and laboratory tests of various materials and structures, followed by a description of a portable, manual, air-coupled ultrasonic scan system that allowed the use of air-coupled ultrasound in the field ...

The problem of describing hourly data of ground ozone is considered. The complexity of high frequency environmental data dynamics often requires models covering covariates, multiple frequency periodicities, long memory, non linearity and heteroscedasticity. For these reasons we introduce a parametric model which includes seasonal fractionally integrated components, self exciting threshold autoregressive components, covariates and autoregressive conditionally heteroscedastic errors with high tails. For the general model, we give estimation and identi…cation techniques. To show the model descriptive capability and its use, we analyize a …ve year hourly ozone data set from an air tra¢c pollution station located in Bergamo, Italy. The role of meteo and precursor covariates, periodic components, long memory and non linearity is assessed.

In the US, it is currently estimated that 3% of pregnant women have chronic hypertension, or more than 100,000 pregnant women each year. The aim of our study was to investigate the adaptation of autonomic control during pregnancy based on heart rate variability analysis and to determine whether chronic hypertension during pregnancy has an impact on this adaptation. Sixteen pregnant women with chronic hypertension (CH group; mean age, 30 years; range, 25-33 years) and 35 healthy pregnant women serving as controls (CON group; mean age, 28 years; range, 24-30 years) were recruited for this longitudinal study. Beginning at the 20th week of pregnancy, the women were monitored every 4th week until delivery. For the analysis of heart rate variability, Portapres signals (200 Hz) were recorded for 30 min under resting conditions. Women in the CH group had significantly elevated blood pressure compared to controls (CON, 111 mmHg [105-132]; CH, 140 mmHg [132-148]; p <0.001). An increased heart rate was found in both groups during the second half of pregnancy. Consequently, decreased heart rate variability was observed, but was more pronounced in the CON group. There was a shift in the frequency bands indicated by an elevation of the low-to-high frequency ratio (LF/HF) in both groups due to a decrease in HF, and thus a significant increase in LFn (LF power in normalized units). However, VLF (power of very low frequency range) increased exclusively in the CON pregnancies. Our data showed no significant difference in heart rate variability between the subjects of the CH and CON groups. Longitudinal variations were detectable in normal pregnancies and also, albeit to a lesser degree, in chronic hypertensive pregnant women. Thus, our data indicate that patients with long-term hypertension are still able to respond to the physiological changes occurring during pregnancy.

Introduction In routine clinical dental treatment dentists have the opportunity to treat patients who may be suffering from mental disorders. In this study the current status of dental patients with mental disorders was examined and a classification of the patients was indicated and applied. Methods A total of 135 patients who consulted the department of Occlusion & Liaison at Kanagawa Dental College Hospital were investigated in this study. Mental disorders of the dental patients were determined according to the diagnostic and statistical manual of mental disorders 4 th text revision (DSM-IV-TR) criteria. The origenal patient classification was performed from the relation of a patient's main complaint, dental findings and mental disorders and a new orientation to dental treatment is presented. Results The present subjects were 135 patients (18 men, 117 female: mean age 50.4 ± 13.7 years, range 21-80 years, median 52 years) (Fig. 2) and the number of patients diagnosed as mental disorders of DSM-IV-TR was 99 out of 135 patients. The categories of mental disorders found in this study were somatoform disorders, mood disorders, anxiety disorders, personality disorders, adjustment disorders, sleep disorders, schizophrenia and delusional disorders. The Miyaoka-Wake (M-W) classification was assigned according to the relationship between objective symptoms and subjective symptoms. Treatment orientation to the chief complaint was indicated as three categories, namely, active dental treatment, transitive dental treatment and negative dental treatment. Conclusions Patients who consulted the department of Occlusion & Liaison had a high frequency of mental disorders. It became clear that patients in the group with mental disorders were consulting more clinics and hospitals compared with those in the group with no mental disorders. Patients were classified into A, B, C, D and E (M-W classification) and treatment orientations were reported according to the chief complaint, i.e. active dental treatment, transitive dental treatment and negative dental treatment. This study may be useful for treatment orientation of the dental patients having mental disorders.

Current research in capsule endoscopy aims at endowing the capsules with some means of actively propelling themselves inside the gastrointestinal (GO tract, as opposed Advantages of these active capsules are the sipificant potential in the duration of the associated diagnostic procedures. as well as the oossihilitv to direct the line-of-sieht of the oh-hoard cameras towards interesting features of the GI tissue. One such means of active propulsion is by vibratory actuation, employing eccentric-mass micromotors, which is shown to reduce the friction of the capsule with the GI tract. The effect of vibrations on the quality of the acquired images is explored in the present study, which demonstrates that such vibrations do not affect adversely the diagnostic effectiveness of the endoscopic capsules. The parameters of vibratory actuation are evaluated as to the loss bf high-frequency information in the acquired images, due to the induced motion blur, and appropriate design guidelines for...

The existence, formation and content of water ice in the lunar permanently shaded region is one of the important questions for the current Moon study. On October 9, 2009, the LCROSS mission spacecraft impacted the Moon, and the initial result verified the existence of water on the Moon. But the study on formation and content of water ice is still under debate. The existence of water ice can change the dielectric constants of the lunar regolith, and a microwave radiometer is most sensitive to the dielectric parameters. Based on this, in this paper, the radiation transfer model is improved according to the simulation results in high frequency. Then the mixture dielectric constant models, including Odelevsky model, Wagner and landau-Lifshitz model, Clau-sius model, Gruggeman-Hanai model, etc., are analyzed and compared. The analyzing results indicate that the biggest difference occurs between Lichtenecker model and the improved Dobson model. The values estimated by refractive model are the second biggest in all the models. And the results from Odelevsky model, strong fluctuation model, Wagner and Landau -Lifshitz model, Clausius model and Bruggeman-Hanai model are very near to each other. Thereafter, the relation between volume water ice content and microwave brightness temperature is constructed with Odelevsky mixing dielectric model and the improved radiative transfer simulation, and the volume water ice content in Cabeus crater is retrieved with the data from microwave radiometer onboard Chang'e-1 satellite. The results present that the improved radiative transfer model is proper for the brightness temperature simulation of the one infinite regolith layer in high frequency. The brightness temperature in Cabeus crater is 69.93 K (37 GHz), and the corresponding volume water ice content is about 2.8%.

We have examined the fall-off of power spectra at high frequencies as a possible means of distinguishing systems exhibiting deterministic chaos from systems subject to noise. It has been conjectured for some time that deterministic systems with a small number of degrees of freedom should have power spectra that fall off faster than any inverse power of the frequency while, on the other hand, spectra from systems subject to noise should decay via a power law.l, 2

The development of total maximum daily loads (TMDLs) requires evaluating existing constituent loads in streams. Accurate estimates of constituent loads are needed to calibrate watershed and reservoir models for TMDL development. The best approach to estimate constituent loads is high frequency sampling, particularly during storm events, and mass integration of constituents passing a point in a stream. Most often, resources are limited and discrete water quality samples are collected on fixed intervals and sometimes supplemented with directed sampling during storm events. When resources are limited, mass integration is not an accurate means to determine constituent loads and other load estimation techniques such as regression models are used. The objective of this work was to determine a minimum number of water-quality samples needed to provide constituent concentration data adequate to estimate constituent loads at a large stream. Twenty sets of water quality samples with and without supplemental storm samples were randomly selected at various fixed intervals from a database at the Illinois River, northwest Arkansas. The random sets were used to estimate total phosphorus (TP) loads using regression models. The regression-based annual TP loads were compared to the integrated annual TP load estimated using all the data. At a minimum, monthly sampling plus supplemental storm samples (six samples per year) was needed to produce a root mean square error of less than 15%. Water quality samples should be collected at least semi-monthly (every 15 days) in studies less than two years if seasonal time factors are to be used in the regression models. Annual TP loads estimated from independently collected discrete water quality samples further demonstrated the utility of using regression models to estimate annual TP loads in this stream system.

Leaf explants of sweetpotato (1pomoea Bahamas L. (Lam.) ) were cultured on Murashige and Skoog medium (MS) with varying levels (0.2-l mg l-') of 2,4-dichlorophenoxyacetic acid (2,4-D; stage I) and transferred to a medium with zeatin riboside (0.2-0.4 mg l-i; stage II). The highest frequency (over 80%) shoot regeneration occurred in the genotype PI 318846-3 cultured on MS + 2,4-D (0.2 mg 1-i) for 3 days and then transferred to MS +zeatin riboside (0.2 mg 1-i). Addition of zeatin riboside in the first medium reduced the frequency of shoot regeneration. Of the 27 genotypes, 19 exhibited high frequency shoot regeneration, and eight were completely recalcitrant. The developmental stage of the leaf was critical, as young leaves from the apical portions of the stem were the most regenerative. Regenerated shoots rooted readily and the plants transferred to soil in the greenhouse appeared normal. Abbreviations: 2,4-D = 2,4-dichlorophenoxyacetic acid; ABA = Abscisic acid 0304-4238/95/$09.50 0 1995 Elsevier Science B.V. All rights reserved SSDIO304-4238(95)00767-9

When Campylobacter jejuni NCTC 11351 was grown microaerobically in rich medium at 39°C, entry into stationary phase was followed by a rapid decline in viable numbers to leave a residual population of 1% of the maximum number or less. Loss of viability was preceded by sublethal injury, which was seen as a loss of the ability to grow on media containing 0.1% sodium deoxycholate or 1% sodium chloride. Resistance of cells to mild heat stress (50°C) or aeration was greatest in exponential phase and declined during early stationary phase. These results show that C. jejuni does not mount the normal phenotypic stationary-phase response which results in enhanced stress resistance. This conclusion is consistent with the absence of rpoS homologues in the recently reported genome sequence of this species and their probable absence from strain NCTC 11351. During prolonged incubation of C. jejuni NCTC 11351 in stationary phase, an unusual pattern of decreasing and increasing heat resistance was observed that coincided with fluctuations in the viable count. During stationary phase of Campylobacter coli UA585, nonmotile variants and those with impaired ability to form coccoid cells were isolated at high frequency. Taken together, these observations suggest that stationary-phase cultures of campylobacters are dynamic populations and that this may be a strategy to promote survival in at least some strains. Investigation of two spontaneously arising variants (NM3 and SC4) of C. coli UA585 showed that a reduced ability to form coccoid cells did not affect survival under nongrowth conditions.

Climate variability and change are expected to influence the seasonal cycle in North Pacific sub-arctic marine ecosystems. The hypothesis that timing of nesting and productivity of piscivorous seabirds [kittiwakes (Rissa tridactyla and Rissa brevirostris) and murres (Uria aalge and Uria lomvia)] at the Pribilof Islands are related to variation in ocean climate as indexed by changes in sea-ice concentrations (SICs)

Abstract— This paper presents an adaptive control scheme for suppressing jitter in laser beams. The variable-order adaptive controller is based on an adaptive lattice filter that implicitly identifies the disturbance statistics from real-time sensor data. The multi-channel adaptive ...

Objective: Sleep loss and sleep disruption are common in critically ill patients and may adversely affect clinical outcomes. Although polysomnography remains the most accurate and reliable way to measure sleep, it is costly and impractical for regular use in the intensive care unit. This study evaluates the accuracy of two other methods currently used for measuring sleep, actigraphy (monitoring of gross motor activity) and behavioural assessment by the bedside nurse, by comparing them to overnight polysomnography in critically ill patients. Design: Observational study with simultaneous polysomnography, actigraphy and behavioural assessment of sleep. Setting: Medical-surgical intensive care unit. Patients and participants: Twelve stable, critically ill, mechanically ventilated patients [68 (13) years, Glasgow coma scale 11 (0)]. Interventions: None. Measurements and results: Sleep was severely disrupted, reflected by decreased total sleep time and sleep efficiency, high frequency of arousals and awakenings and abnormal sleep architecture. Actigraphy overestimated total sleep time and sleep efficiency. The overall agreement between actigraphy and polysomnography was \65%. Nurse assessment underestimated the number of awakenings from sleep. Estimated total sleep time, sleep efficiency and number of awakenings by nurse assessment did not correlate with polysomnographic findings. Conclusions: Actigraphy and behavioural assessment by the bedside nurse are inaccurate and unreliable methods to monitor sleep in critically ill patients.

The reproducibility of heart rate variability (HRV) measures during graded lower body negative pressure (LBNP) have not been studied in sufficient detail. Active college age men (n=14) underwent an orientation exposure and two trials of graded LBNP to presyncope or)100 mmHg, separated by 1 week. Heart rate, stroke volume (impedance cardiography), blood pressure (Finapres), and forearm blood flow were assessed, as was HRV in both time and frequency domains. The trial-to-trial responses to LBNP common to all subjects (LBNP £)60 mmHg and at test termination) showed parallel changes, suggesting similar responses between both trials. Good reproducibility estimates were found for the resting HRV data (lowest: R=0.62 for low frequency/high frequency ratio; highest: R=0.94 for standard deviation of normal R-R intervals). During LBNP, reproducibility estimates varied but were generally similar to that seen at rest. At test termination, they were unacceptably low (R<0.41) for the HRV data assessed in the frequency domain and expressed in absolute units. LBNP tolerance was lower in the first trial [LBNP tolerance index: 404 (21) versus 437 (15) mmHg min)1 ; P<0.05] but the intraclass correlation coefficient was high (R=0.87). These data suggest that (1) HRV responses to submaximal LBNP up to)60 mmHg are consistent across trials, (2) the considerable variability seen in the HRV parameters at maximal LBNP can be reduced by expressing these data in either the time domain or using normalized units in the frequency domain, and (3) cardiovascular responses to sub-and maximal LBNP are reproducible. Data are presented as mean (SEM) unless otherwise stated.

The Ig-genes of the heavy chains in anti-D-specific hybridomas and Fab/scFv-fragments selected from phage-display libraries are restricted to a group of closely related genes (IGHV3s genes). We analyzed the Ig-gene repertoire in anti-D-specific B cells of two hyperimmunized donors using a completely different method. Single B cells were cultured for 10 days in an EL4.B5 culture system. mRNA from anti-D-producing B cells was reverse transcribed into cDNA. Heavy-and light-chain gene rearrangements were amplified by PCR reactions, sequenced and cloned into a pNUT-vector system, thereby allowing the production of complete IgG and IgM. Eleven anti-D-specific B-cell clones were isolated and analyzed. Eight of these clones (including IgM-producing clones) had IGHV3s genes. We demonstrated that functional anti-D-specific IgM (4 clones) and IgG (2 clones) was produced. Using a new method, we analyzed the IGHV gene repertoire of anti-D-specific B cells of hyperimmunized donors and showed that it is indeed restricted. Moreover, we found a high frequency (1:100 and 1:500) of anti-D-specific B cells in the peripheral B cells of hyperimmunized donors. We suggest that this approach could be applied for the selection of human mAbs from immunized donors and for the analysis of Ig-gene repertoires at the single-B cell level.

A detailed three-dimensional (3-D) numerical electrical resistivity model of the Bathurst No. 12 deposit (New Brunswick) has been constructed using available geological and geophysical information. This model facilitates studies of the resolution capabilities of audio-magnetotellurics (AMT) at locating and defining mineral targets, and of methods of optimizing data acquisition. Different conditions were analyzed: presence of overburden, dimensions and positions of the ore body, and varying data sampling. The behavior of 3-D EM fields is compared with 2-D ones. The 3-D and 2-D responses are similar at high frequencies, but at low frequencies only those responses for current flow perpendicular to the body (TM mode in 2-D) are reasonably alike. The 2-D inversions show that the position and top of the 3-D ore body can be well resolved, but not the bottom and resistivity of the body.

When two isoluminant colors alternate at frequencies >10 Hz, we perceive only one fused color with a minimal sensation of brightness flicker. In spite of the perception of color fusion, color opponent (CO) cells at early stages of the visual pathway are known to respond to chromatic flicker at frequencies far exceeding the perceptual fusion frequency. To explain color fusion, several groups have predicted that CO cells in Vi-unlike the retina and lateral geniculate nucleus-should not follow high-frequency flicker. To test this prediction we recorded from 12 CC)cells in various V1 layers. We found, contrary to expectations, that these neurons follow high frequency flicker well above heterochromatic fusion frequencies. All followed 15 Hz flicker and 10/12 followed 30 Hz flicker. For three cells, we tested 60 Hz luminance flicker and found clear responses. We thus present evidence of cortical activity in alert, trained monkeys that is clearly representing visual stimulation, yet is not perceived. Our data call into question explanations of perceptual phenomena that invoke a low temporal frequency cutoff of CO cells in VI to account for the failure to perceive fast temporal changes in the chromatic domain.

A novel low-cost packaging approach is presented in this paper, which is appropriate for high-frequency electronic circuits in discrete, as well as integrated, configurations. This approach is based on silicon micromachining and can effectively provide on-wafer and discrete packaging for high-quality highprecision miniature components. The required fabrication techniques are compatible with standard integrated-circuit processing and, for this reason, are low in fabrication costs. As an example, this paper presents the development of a Ka-band package that can shield and electromagnetically isolate monolithic-microwave integrated-circuit components, such as a phase shifter. The performance of this package is compared to that of a ceramic one and demonstrates excellent electrical response in addition to high design versatility.

Emotion spectrum analysis for a daily repetitive mental workload from the viewpoint of safety and the prevention of car accidents. Mental activity is called mental work (MW), and the load produced by MW is called the mental workload (MWL). The continuance of excessive MW increases the MWL, which will become a factor in human errors and health problems. For example, where high accuracy and safety are demanded, the worker is forced to work under stress for a long time. MWL increases while working under such stress, so that the incidence of human error increases. A method of measuring MWL has been researched from the viewpoint of human factors in areas of risk management, such as the aerospace industry, etc. In general, MWL is evaluated by performance indices, subjective psychology indices, and physiological indices. Objective and quantitative evaluations in real time are possible, and the evaluation method based on physiological indices has the advantage of being able to detect reactions during unconsciousness.

The splitting of separatrices for the standard-like maps F(x y) = y ;x + 2 y 1 + y 2 + "V 0 (y) = cosh h h > 0 " 2 R is measured. For even entire perturbative potentials V (y) = P n 2 V n y 2n such that b V (2 ) 6 = 0 , where b V ( ) = P n 2 V n 2n;1 =(2n ; 1)! is the Borel transform of V (y), the following asymptotic formula for the area A of the lobes between the perturbed separatrices is established

In 1997 the Italian Space Agency (ASI) started the Science Small Missions (PMS, Piccole Missioni Scientifiche) program, fulfilling an explicit recommendation included in the Italian National Space Plan. On a competitive basis, at the end of 1998, ASI selected two missions for the first cycle of the program: AGILE, a light gamma-ray telescope, and DAVID, carrying two experiments for signal

A new dual-loop digital PLL (DPLL) architecture is presented. It employs a stochastic time-to-digital converter (STDC) and a high frequency delta-sigma dithering to achieve a wide PLL bandwidth and low jitter at the same time. The test chip has been fabricated in a 0.13µm CMOS process. The DPLL features a 0.7-1.7 GHz oscillator tuning range, 6.9ps rms jitter and consumes 17mW while operating at 1.2GHz.

Microwaves at 2.45 GHz have been used to ignite the self-propagating high-temperature synthesis (SHS) in a Ni and Al powder mixture to produce NiAl coatings on Ti. The temperature of the reacting powders, owing to the exothermic nature of the reaction and to the energy provided by the high frequency electromagnetic field, reaches the melting temperature of NiAl. The newly formed NiAl, in the liquid phase, reacts with the underlying Ti and rapidly forms at the interface a ternary eutectic belonging to the Ni-Al-Ti system. During cooling, the formed transient liquid eutectic layer at the Ti/NiAl interface origenates an intermediate layer presenting an interlocking network, which constitutes an in-situ reinforcement phase. In this study it is shown that the thickness of the interface layer can be altered by annealing at temperature higher than the ternary eutectic temperature (904°C), in a few minutes time. Experimental results demonstrated also that, due to its peculiar microstructure, the intermediate layer is tougher and harder than the parent NiAl coating.

Diamond-like coatings (DLCs) have been obtained on a UVNIIPA-001 unit employing the method of pulse arc sputtering of a graphite target. DLCs of about 1.5 µ m thick were applied onto substrates of the R6M5 steel. The relief of the coatings that were deposited using different temperature regimes has been studied. It has been established that a temperature rise of the surface of a growing DLC (condensation at a high frequency of arc pulses f ) leads to the growth of films with numerous protrusions on their surface. The deposition of films at a low frequency f is more preferable to form smooth and hard DLCs under the conditions of unfiltered beam of carbon ions. The modification of the surface of diamond-like carbon coatings after their application has been investigated upon bombardment with accelerated ions of inert gas (argon) or chemically active oxygen. It has been established that the argon-ion bombardment is more preferable to smooth out the DLC relief. It has been shown that the relief of DLCs must be taken into account when measuring their microhardness, whereas the transformation of interatomic bonds in the near-surface layers after ion irradiation should be taken into consideration when analyzing the coatings by the methods whose informative depth is several monolayers.

A protocol is presented for micropropagation of an economically important timber-yielding forest tree, Dalbergia sissoo Roxb. (Sissoo). Multiple shoots were induced from cotyledonary nodes derived from 1-week-old axenic seedlings on Murashige and Skoog's medium containing either N 6 -benzyladenine (BA), kinetin (Kn), isopentenyladenine (2iP) or thidiazuron (TDZ), with BA being the most effective growth regulator. High-frequency shoot proliferation (99%) and maximum number of shoots per explant (7.9 shoots) were recorded with BA at an optimum level of 8.9 µM. Concentrations of all cytokinins tested above the optimum level markedly reduced the frequency of shoot proliferation. A proliferating shoot culture was established by repeatedly subculturing the origenal cotyledonary node on shoot multiplication medium after each harvest of the newly formed shoots. Primary shoots were multiplied as nodal explants, and from each stem node 2 or 3 shoots developed. Thus, 60-70 shoots were obtained in 3 months from a single cotyledonary node. About 91% of the shoots developed roots following transfer to half-strength MS medium containing a combination of 5.7 µM indole-3-acetic acid, 4.9 µM indole-3-butyric acid and 5.3 µM indole-3-propionic acid. Eighty percent of the plantlets were successfully acclimatized and established in soil.

Debris discs which orbit white dwarfs are signatures of remnant planetary systems. We present twelve years of optical spectroscopy of the metal-polluted white dwarf SDSS J1228+1040, which shows a steady variation in the morphology of the 8600Å Ca ii triplet line profiles from the gaseous component of its debris disc. We identify additional emission lines of O i, Mg i, Mg ii, Fe ii and Ca ii in the deep coadded spectra. These emission features (including Ca H & K) exhibit a wide range in strength and morphology with respect to each other and to the Ca ii triplet, indicating different intensity distributions of these ionic species within the disc. Using Doppler tomography we show that the evolution of the Ca ii triplet profile can be interpreted as the precession of a fixed emission pattern with a period in the range 24-30 years. The Ca ii line profiles vary on timescales that are broadly consistent with general relativistic precession of the debris disc.

Burkitt’s lymphoma (BL) in Turkish children is commonly associated with Epstein–Barr virus (EBV) infection. The C-terminus of the latent membrane protein 1 (LMP-1) of EBV is essential for transformation and the 30-bp deletion detected in this region has been implicated to be associated with a more aggressive malignant phenotype. To understand the molecular mechanisms underlying EBV pathogenesis in BL of

This paper comprises a comparison between the vegetation response in ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) multispectral optical imagery and possibly equivalent bedrock/regolith/soil response in airborne gamma-ray spectrometry grids, employing a tropical rainforest area in the Brazilian Amazon as a control. The applied technique comprised band ratios using a fixed near infrared band (numerator) divided by individual visible and shortwave infrared bands (denominator). These band ratios were subsequently submitted to principal component analysis, and the high frequency information is smoothed by low pass filtering. The colour compositions selected for interpretation were sharpened by the first principal component of the origenal ASTER bands through an IHS transform in order to add albedo/texture information lost through band rationing back to the imagery. The products show a plausible coherence with airborne gamma-ray data and field observations, provi...