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In recent years. pure states have been found in some micromaser systems such as the one and two photon micromasers as well as in the A system.1–6

From experiments in animals and investigations in humans it is known that the normally phase-dependent masking of a short stimulus by a low-frequency continuous tone does not occur in the case of endolymphatic hydrops. The recording of the masked threshold of short tone stimuli in a loud tone of 30 Hz is to be evaluated for the clinical diagnostics of Ménière's disease. To this purpose, the main parameters of the measurements (type, frequency, duration of the stimulus, and intensity of the masker) and their effect of phase-dependent masking and pitch-shift are investigated. Stimuli above 2 kHz are masked less than those of lower frequencies. Wide-band stimuli are less useful, since only the low-frequency component of their spectrum is masked. The tone stimuli should be short (1 - 2 ms) in order to make the measurement of the phase dependence more accurate. With increasing masker level the masking at phase 0 degree corresponds to the increase in level, at phase 270 degrees the amount is twice as much. The pitch shift which is perceived in low-tone masking depends on the phase of the stimulus, and on the levels of the stimulus and the masking tone. The use of brain stem recordings in the investigation of phase-dependent low tone masking is problematic since well-synchronizing stimuli with high frequency spectral components are masked poorly.

The Nova HR Del, discovered in 1967, was found to be exceptionally bright in the optical and UV during the whole lifetime of the IUE satellite (ending in 1996) and appears to be still extremely luminous today. The reason for this continuing activity is not clear; continuing weak thermonuclear burning might be involved. HR Del was thus monitored over several years, both in broad band photometry and spectroscopically in the H$\alpha$ spectral region. The profile of the H$\alpha$ line shows two components: a narrow, central component; and broader wings. The former is most easily understood as being due to an accretion disk, whose geometry might lead to it partly occulting itself. That component shows something like an S wave with an orbital phase dependance, suggesting that it could be due to a spot bright in H$\alpha$. The wide component must come from another region, with a probably non-negligible contribution from the material ejected during the 1967 outburst. Non-orbital variations of the H$\alpha$ equivalent width were found both on long and short time scales. Similar variations were found in the photometry, showing a component with a clear dependence on the orbital phase, but no obvious relation with the H$\alpha$ variations. The orbital part of the photometric variations can be explained by irradiation of the companion, while the properties of H$\alpha$ are explicable by the presence of an accretion disk and a spot bright in H$\alpha$., Comment: 12 pages, 15 figures, accepted for publication in Astronomy & Astrophysics

Coalescence of precipitates is a common kinetic phenomenon. The phase-field method can simulate coalescence of precipitates without any ad hoc assumptions. However, independent of long range effects (e.g. lattice misfit) the method predicts a high coalescence rate when applied to systems with a high volume fraction of precipitates. We show that this is a result of ignoring the local phenomenon in the interface regions, which is an approximation adopted by many other simulation techniques. An improved coalescence rate is achieved by properly addressing this local phenomenon through introducing composition and phase dependence of diffusion mobility.

We discuss the significance of polarization producing mechanisms in determining the physical conditions in models of neutron star high energy sources, and the possible impact of polarization measurements at high energies in determining the geometry of the emission regions. Current experiments and their capabilities are reviewed. We discuss calculations of the expected polarization from nonmagnetic neutron stars with accretion disks, and the pulse phase dependence of the degree and angle of polarization in magnetized accreting X-ray pulsars. Calculations of the polarization of gamma-ray burst sources and accreting pulsars are presented, with particular attention to the cyclotron line energy range, using relativistic two-photon processes.

Purpose: Interplay between IMRT multi‐leaf collimator(MLC) delivery and patient's breathing motion can affect the delivered dose distribution. Interplay is the correlated effect between MLC‐delivery and organ‐motion, due to either MLC motion or initial breathing phase dependence of MLC‐delivery. This study investigated the clinical relevance of interplay for lungIMRT plans assuming free‐breathing delivery. Method and Materials: An in‐house developed 4D Monte Carlo system was used for patient dose calculations. Three patients with lungcarcinoma were studied, where motion‐amplitude was 1–2cm. A voxel‐displacement‐map was used to quantify the non‐rigid motion of organs in the CT‐geometry. In order to quantify the MLC position relative to the breathing phase, each photon going through the linac head is tagged to indicate the associated breathing phase during which it will enter the patient. 4DCT data was sorted into 6‐phases, inhale, exhale, 2 phases from inhale to exhale, and 2 phases from exhale to inhale. The exhale phase was used as reference phase. Interplay effects were studied on a beam‐by‐beam basis for a treatment in 30 fractions. Different starting initial MLC phases relative to the breathing motion were selected per daily fraction. Results: The volume of ITV covered by 5–15Gy isodose lines can vary up to 10% relative to the average volume covered per beam over 30‐fractions. Organ motion causes in some instances the dose to be primarily delivered to phases close to inhale and in other cases delivered to phases close to exhale, i.e. the reference phase. For hypo‐fractionation (10–15 fractions), the volume of ITV covered by 5–15Gy isodose lines can vary up to 12–15% relative to mean volume covered over 30‐fractions. Conclusion: Interplay between MLC‐delivery and organ motion can lead to under‐dosed regions in the ITV volume.

Optically pumped NMR (OPNMR) of direct gap and indirect gap semiconductors has been an area of active research interest, motivated by both basic science and technological perspectives. Proposals to enhance and to spatially localize nuclear polarization have stimulated interest in this area. Recent progress in OPNMR has focused on exploring the experimental parameter space in order to elucidate details of the underlying photophysics of optical pumping phenomena. The focus of this review is on recent studies of bulk samples of GaAs and InP, namely, the photon energy dependence, the magnetic field dependence, and the phase dependence of OPNMR resonances. Models for the development of nuclear polarization are discussed.

The aim of this study is to establish the structure-properties relationship of tetrathiafulvalene (TTF). After this study (1) TTF crystals with α and β phases were controllably obtained by the cast method with careful selection of the solvents, and (2) organic field-effect transistors (OFETs) of α and β phases both exhibited field-effect performance, and the performance of α phase was much better than that of β phase. The highest mobility of α phase reached 1.2cm2V−1s−1, while β phase showed the maximum mobility only about 0.23cm2V−1s−1, indicating the strong performance dependence of OFETs performance on the crystal phases.

Joffre attempts to show that the linear response of any quantum system to an external perturbation is phase insensitive, but he uses incorrect mathematical assumptions, misinterprets the time invariance principle, and ignores causality. We argue that the opposite case—an explicit phase dependence for a signal measured in the linear excitation regime—can equally be shown using Joffre's approach and assumptions.

Signals that propagate from submerged sources to deep receivers in the ocean generally interact less with the fluctuation generation mechanisms near the sea surface than do clutter signals and noise which originate near the surface. As a result, signals from submerged sources generally have smaller fluctuations than clutter signals and noise. The order dependence in the amplitudes of fluctuations has been used to devise an environmentally adaptive signal processing algorithm that provides preferential gains for signals having smaller fluctuation amplitudes than those of clutter and noise [R. A. Wagstaff and J. A. Mobbs, J. Acoust. Soc. Am. 101, 3027 (1997)]. Gains include increases in signal‐to‐noise ratio, clutter suppression, and unalerted automatic detection. Similar gains can be achieved by exploiting the fluctuations in the phases of the acoustic pressures in the same manner that the order dependence was exploited. By replacing the order dependence with phase dependence, a similar algorithm has been ...

In DC transport through mesoscopic S-N-S junctions, it is known that the Josephson coupling decreases exponentially with increasing temperature, but the phase dependence of the conductance persists to much higher temperatures and decreases only as 1/T. It is pointed out here that, despite the fact that such a phase-dependent conductance does bring about an AC current for a pure DC voltage, it cannot, by itself, lead to the formation of Shapiro steps.

A discussion of the evolution of the HE12 (LP02) field, and thus the role of the core in HE11-H12 (LP01-LP02) local-mode coupling for a tapered ‘doubly-clad’ lightguide as may be formed by the combination finite-cladding fibre and external medium (i.e. outer cladding) is presented. Consideration of more than one interface injects interesting novel features into the local-normal-mode viewpoint: examination of the HE12 lobe maximum and field evolution leads to the discovery of a core/cladding bounce phenomenon (related to an HE12 leaky-mode property) as well as an intriguing coupling phase dependence.

Stimulus-like properties of the 2f1-f2 cubic difference tone (CDT) were examined by determining whether a binaural masking-level difference (BMLD) could be obtained for a 500-Hz physical tone to one ear and a CDT of the same frequency to the other ear. Masked thresholds for the physical tone (signal) were obtained as the phase of this tone varied through 360 degrees relative to harmonically related primaries (f1 = 625 Hz, f2 = 750 Hz). A continuous low-pass (2000 Hz) diotic noise comprised the masking stimulus. The level of this noise was varied to establish thresholds in a two-interval same-different adaptive procedure with the primaries occurring in both observation intervals. In keeping with other stimulus-like properties of the CDT, the results show BMLDs of 10-13 dB. Additional BMLDs were obtained with a method of adjustment to derive phase and level estimates of the CDT as a function of primary level. These estimates are compared to cancellation estimates obtained from the same subjects. Both BMLD and cancellation estimates of CDT level show a 10-dB growth in the CDT with each of 10-dB increase in primary level. However, cancellation-level estimates are consistently above corresponding BMLD-level estimates, greater by an average of 4-14 dB, depending on the subject. BMLD and cancellation estimates of CDT phase show a near-identical dependence on primary level, decreasing by an average of 5 degrees/dB. The agreement between the two procedures argues against the notion that the phase dependence is the result of confounding peripheral interactions between the cancellation tone and the primaries in the cancellation procedure.

The problem of point source transmission through a sinusoidal ocean surface is considered. There are three basic approximations used. (1) The sound wavelength in air should be much less than the radius of curvature of the sinusoidal surface. (2) The maximum surface slope of the sinusoidal surface should be small. (3) The source and receiver distances should be very much greater than k1ζ02 where k1 is the wave numer in air and ζ0 is the amplitude of the ocean surface. This last restriction leads to the useful result that the phase dependence of the field upon ζ is linear. The result of the theory presented here is that in most cases there is relatively little change in the intensity of the field for the sinusoidal surface from that experienced for a flat surface. However, there are changes of several decibels which can be experienced primarily as a result of coherence between the various diffracted components being transmitted into the water region. A novel aspect is that there can be sound transmission for the sinusoidal surface from regions where the flat surface sould totally reflect.

Ion beam mixing was employed as an unique method to study the microscopic features of ion induced Fe−Cu phase dependence on increasing ion doses. The multiple metastable phases were observed by transmission electron microscopy. The phase identification was carried out by selected area electron diffraction and the corresponding compositions of the observed phases were determined by energy dispersive spectroscopy.

Spectral reflectivities ϱ(λ) of the features on the disk of Jupiter (NTrZ, NEB, EZ, SEB, STrZ) and the center of the disk of Saturn were measured for different phase angles. The phase dependence of ϱ(λ) is shown to correspond to the shape of the phase function.

Temperature and pressure dependent exchange broadened NMR spectra of gaseous methyl nitrite are consistent with the following kinetic parameters for the syn–anti conformational interconversion: Eact (∞), 12.2(4) kcal/mol; Eact (bimolecular), 9.6(2) kcal/mol; ΔH‡, 11.7(4) kcal/mol; ΔG‡298 11.97(7) kcal/mol; and ΔS‡298 , −0.9(4) cal/mol K. Kinetic parameters for interconversion in the neat liquid and in a 1% solution in CS2 are slightly higher: Eact; 12.9(2); ΔH‡, 12.4(2) kcal/mol; ΔG‡, 11.81(8) kcal/mol; and ΔS‡, 2.6(2) cal/mol K. These remarkably small solvent effects indicate that dielectric effects on conformational dynamics in this system are nearly equal in magnitude and opposite in direction to solvent internal pressure effects.

The time evolution of fluctuations in a squeezed single-mode field interacting with a two-level atom initially in a coherent superposition of excited and ground states is treated. The phase dependence is discussed.

Gas phase 1 H NMR spectra of N,N -dimethylnitrosamine are consistent with first order chemical exchange rate constants which are ca. 25 times faster than those observed in neat liquids at corresponding temperatures. The associated kinetic parameters: E act (∞), 20.5(1.1) kcal mol −1 , Δ H ‡ , 19.7(1.0) kcal mol −1 and Δ G ‡ , 21.1(0.4) kcal mol −1 are approximately 2.5 kcal mol −1 lower than the most recently reported values for the neat liquid. The observed phase dependence is consistent with a process proceeding via a freely rotating transition state.

In stick insects walking forwards or backwards, a treading-on-tarsus (TOT) reflex of the middle leg could be elicited by mechanical stimulation of the ipsilateral front leg tarsus. The probability of eliciting a TOT reflex in the middle leg depended on the phase of the stimulus within the middle leg’s step cycle and on the position of the middle leg relative to its normal anterior and posterior extreme positions. During a TOT reflex the functional swing muscle (protractor coxae in forward walks and retractor coxae in backward walks) was inhibited while the functional stance muscle was activated. This suggests that the step generator of the middle leg contains two hierarchical levels: the higher level would determine the timing of swing and stance independent of walking direction; the lower one would drive the appropriate muscle groups for swing and stance depending on which programme -forward or backward walking -was running. The stimulus information from the front leg necessary to elicit a TOT reflex was observed only in the ipsilateral connective. In terms of the model, this information would have to be processed according to the actual state of the higher level of the step generator. Movement and position of the front leg and tarsal contact of the middle leg were not relevant for the TOT reflex of the middle leg. Steps with a TOT reflex were significantly prolonged, and compensation for this disturbance of walking coordination was made within the next step.

From a systematic analysis of the available balloon data for searching variabilities in the time-scales of days for Cyg X-1, the first evidence for the existence of a distinct phase dependence of intensity at 30 keV, corresponding to a period of 5.6 days, is presented. Additionally, the existence of a two-state X-ray emission at these energies is also indicated. Implications of these variabilities on the existing models of Cyg X-1 are discussed.

The already well known sensitivity of genuine quantum effects to loss processes is investigated for squeezing. Owing to the phase dependence of its quantum fluctuations, a squeezed state is extraordinarily fragile with respect to phase-destroying processes. This sensitivity increases with increasing degree of squeezing. A present coherent photon number enhances this disturbing effect.

A practical method is described for the phase determination of x-ray reflections from single crystals. Considerations on the dynamical interaction in multiple diffraction and on the relative rotation of the crystal lattice with respect to the Ewald sphere reveal both experimentally and theoretically the phase dependence of the reflected intensity. Applications can be made for a direct experimental determination of phases without carrying out the complicated dynamical calculation.

Positron lifetime spectra have been obtained as a function of temperature for various solid mixtures of n-eicosane (C20H42) and n-docosane (C22H46). These compounds, when mixed in various proportions, are known1 to form at least six distinct solid phases. Positron lifetime parameters T 2 and I 2 have been measured in each of these phases and are found to exhibit both a temperature and a phase dependence. Comparison with crystallographic data reveals that t 2 variations in the n-eicosane: n-docosane system depend more strongly on the lattice dimensions a and b than on the dimension c.

ESR spectra and kinetics of hydroxy-phenoxy radicals produced by modulated UV excitation are reported. Analysis of amplitude and phase dependence of the spectra on the modulation frequency of the exciting UV light is used to derive information about mechanisms of the reactions of 2-hydroxy- and 2,3-dihydroxy-phenoxy radicals.

Segmental responses of the lumbosacral region of the spinal cord to peripheral afferent stimulation were studied in decorticated, immobilized cats before and during fictitious locomotion. The appearance of fictitious locomotion was accompanied by a tonic increase in the N1-component of the dorsal cord potential and dorsal root potential. Against the background of this tonic increase, modulation of these responses depending on the phase of fictitious locomotion was observed. When the N1-component and dorsal root potential were evoked at the end of the "extension" phase and at the beginning of the "flexion" phase their amplitude was greater, but when they were evoked at the end of the "flexion" phase and the beginning of the "extension" phase it was smaller. Polysynaptic and monosynaptic reflex response of motoneurons exhibited the same phase dependence during fictitious locomotion. The mechanisms and physiological importance of this retuning of segmental responses are discussed.

In-core neutron detectors were used for noise diagnostic measurement in a commercial PWR NPP. Phase dependence versus frequency between axially placed self powered neutron detectors (SPND) exhibited linear behaviour in some cases. Correlation was found between the existence of linear phase behaviour and the power of the Unit. More thoughtful consideration showed a dependence on local power, and on overheating of the surface of fuel elements. Data extracted from conventional measurement of top of core temperature sensors and in-core SPNDs, using the conventional system for linear power production estimation showed that linear phase takes place where linear power production is over 2 MW/m. One dimensional thermohydraulic calculation pointed out that at those places the surface temperature is near or over the saturation value. Thus the appearance of linear phase versus frequency can be attributed to phenomena of local subcooled boiling and therefore its existence can be used for boiling detection in PWRs. All basic considerations had been checked beforehand in model experiments and are cited here.

Some attempts of polarimetric sounding of Comet Halley will be undertaken from the flyby probes. In order to facilitate the final planning and the future interpretation of these experiments we have done a thorough analysis of practically all available polarimetric observations. An emphasis is made on interpretation attempts and their discussion. The results of the phase dependence of polarization investigations are presented covering a wide range of phase angles α. The chief peculiarities of this dependence are: maximum polarization at α = 90‡, diminishing through zero at α ≈ 20‡, negative values up to several per cent and a final growth to zero at zero α. A division into “gaseous” and “dusty” comets on polarimetric basis is revealed. The wavelength dependence of polarization is discussed. The numerous results of detailed polarimetry are compared to the negative results of attempts to detect the elliptical polarization. New observational problems arising from the evidence given by the negative polarization at small phase angles and by the “opposition effect” recently discovered are discussed.

High pressure values for the adiabatic pressure derivative of temperature ( ∂T ∂P ) s have been obtained by measuring the temperature change caused by a small rapid increase in pressure. Values for KBr and RbCl in phases B1 and B2 and for Bi in phases I, II and III are given for T = 295 K. The Gruneisen parameter γ is given by γ = B s ( ∂T ∂P ) s T where Bs is the adiabatic bulk modulus. Ultrasonic and statk compressibility data are used to estimate the pressure and phase dependence of Bs. Dramatic increases in both γ and (∂T/∂P)s are observed as the pressure increases through a phase transition. Values for the logarithmic derivate q ≡ (∂ ln γ ∂ ln V T are given.

The absolute measurements of the intensity of radio emission of the Moon, carried out with the aid of more advanced equipment and method of calibration, made it possible to reveal its variation with the phase, and yielded the value of the effective temperature for the centre of the disk practically equal toT1= 245° + 15·5° cos(Ωt−50°), the ratio of penetration depth of the electric wave to the thermal wave equal to 6·0, and δ/λ = 2·0.

The dependence of the quadrupolar echoes upon the phase difference between the first and the second r.f. pulse is discussed. Experimental results obtained in KBr are presented.

For several metals like Hg, In, Ga and Tl , we show that the solid-liquid phase transition can generate large changes in the photoemission properties. The temperature or phase dependence of the yield Y(T), workfunction Φ(T), vector-ratio α(T) and the energy distribution curves (EDC) are of special interest here. Thallium shows an additional solid-solid phase transition and offers the opportunity of studying a transition between two different ordered states. Possible reasons for the observed changes at a phase transition are discussed.

Unlike the common spectral transformations (Fourier, Walsh) the method of time-varying spectral analysis (Volke (1983), Volke and Dettmar (1983)) performs a decomposition of the function of interest into components of variable amplitude and frequency. Its application to the analysis of the EEG enables the recognition of stimulus-evoked effects on the level of single post-stimulus records. Some results concerning the Single-EP-analysis (intraserial variability, phase dependence, component detection) are described.

The well known frequency dependence of aortic input impedance suggests the existence of heart rates where the external work needed to eject a given pulsatile flow is minimum (O’Rourke and Taylor, 1967; Nichols et al., 1977). For dogs this minimum is in the range between 180 and 200 beats/min, for men round about 120/min. But a consideration of necessary cardiac work has to take into account also to what extent the heart can profit from this minimum. The heart is confronted with the arterial system only during ejection phase but input impedance is calculated from systolic as well as diastolic pressure and flow values. Thus it is possible that input impedance changes within cardiac cycle. That means the heart sees another resistance during ejection phase than given by calculation of input impedance. Only the effort in developing systolic pressure which is necessary to generate a given systolic flow is relevant to the heart. The ratio between mean pressure during ejection phase and mean flow also measured during ejection phase is called outflow resistance (OR) and often used as a measure for judgement of cardiac performance (Imperial et al., 1961; Wilcken et al., 1964; Liedtke et al., 1972). This outflow resistance describes in the most correct form the effort of the heart to produce pressure needed to eject a certain stroke volume.

The physical parameters of the components of V861 Sco are derived from light-curve analysis and published spectroscopy. Good agreement with evolutionary models is obtained. The stellar wind is investigated using IUE data; the results include no large phase dependence of the mass loss rate and insensitivity of the velocity of the wind (measured with respect to interstellar lines) to changes in the photospheric velocity, even near the base of the wind. However, small random changes in velocity near the base of the wind are amplified to larger changes further out.

A small black object embedded in a black-white contrasted random-dot texture, is easily confused by a human observer with the ground. However, even small relative motions between object and ground allow an easy detection. A similar observation is made when the object is replaced by a figure consisting of the same random-dot texture as the ground. As long as the figure is not moved against the ground, figure-ground discrimination is not possible as the boundary of the figure disappears in the texture of the ground. However, when the figure is moved relative to the ground, the boundary of the figure can be easily seen. In some sense relative motion between figure and ground leads to an independent or context free perception of a figure. The observations are of course different when the texture of the figure differs from the texture of the ground. Under these conditions one can usually see the figure’s boundary and its content even if it is not moved relative to the ground.

Photometric properties of the lunar surface in visual and near-infrared light were studied using raw images obtained with UVVIS camera during the Clementine mission. The investigation focused on several specific regions on the lunar surface, each of which was observed by Clementine at a variety of different illumination and viewing geometries. Through these observations, the dependence of the surface brightness on the observation/illumination geometry was studied. It was shown that the disk component of this dependence, that is, the variations of brightness at constant phase angle, is different for different mare areas. The color of the lunar surface also changes with changing of the observation/illumination geometry, even if under constant phase angle. The Reiner Gamma formation displays unusual photometric properties. They are consistent with the surface being smoother than the typical mare regolith surface. The UVVIS images taken at the smallest phase angles were used to study the opposition spike, that is, the sharp increase of the surface brightness near the opposition. Steepness of the phase dependence of brightness varies over a wide range for different sites.