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The Madden–Julian Oscillation (MJO)/Boreal Summer Intraseasonal Oscillation (BSISO) has been considered an important climate mode of variability on subseasonal timescales for East Asian summer. However, it is unclear how well the MJO/BSISO indices would serve as guidance for subseasonal forecasts. Using a probabilistic forecast model determined through multiple linear regression (MLR) with MJO, ENSO, and long-term trend as predictors, we examine lagged impacts of each predictor on East Asia extended summer (May–October) climate from 1982 to 2015. The forecast skills of surface air temperature (T2m) contributed by each predictor is evaluated for lead times out to five weeks. We also provide a systematic evaluation of three commonly used, real-time MJO/BSISO indices in the context of lagged temperature impacts over East Asia. It is found that the influence of the trend provides substantial summertime skill over broad regions of East Asia on subseasonal timescales. In contrast, the MJO influence shows regional as well as phase dependence outside the tropical band of the main action centers of the MJO convective anomalies. All three MJO/BSISO indices generate forecasts that yield high skill scores for week 1 forecasts. For some initial phases of the MJO/BSISO, skill reemerges over some regions for lead times of 3–5 weeks. This emergence indicates the existence of windows of opportunity for skillful subseasonal forecasts over East Asia in summer. We also explore the dynamics that contribute to the elevated skills at long lead times over Tibet and Taiwan–Philippine regions following the initial state of phases 7 and 5, respectively. The elevated skill is rooted in a wave train forced by the MJO convective heating over the Arabian Sea and feedbacks between MJO convection and SSTs in Taiwan–Philippine region. Two out of the three commonly used MJO/BSISO indices tend to identify MJO events that evolve consistently in time, allowing them to serve as reliable predictors for subseasonal forecasts for up to 5 weeks.

Most small rodent populations in the world have fascinating population dynamics. In the northern hemisphere, voles and lemmings tend to show population cycles with regular fluctuations in numbers. In the southern hemisphere, small rodents tend to have large amplitude outbreaks with less regular intervals. In the light of vast research and debate over almost a century, we here discuss the driving forces of these different rodent population dynamics. We highlight ten questions directly related to the various characteristics of relevant populations and ecosystems that still need to be answered. This overview is not intended as a complete list of questions but rather focuses on the most important issues that are essential for understanding the generality of small rodent population dynamics.

Essential tremor manifests predominantly as a tremor of the upper limbs. One therapy option is high-frequency deep brain stimulation, which continuously delivers electrical stimulation to the ventral intermediate nucleus of the thalamus at about 130 Hz. Constant stimulation can lead to side effects, it is therefore desirable to find ways to stimulate less while maintaining clinical efficacy. One strategy, phase-locked deep brain stimulation, consists of stimulating according to the phase of the tremor. To advance methods to optimise deep brain stimulation while providing insights into tremor circuits, we ask the question: can the effects of phase-locked stimulation be accounted for by a canonical Wilson–Cowan model? We first analyse patient data, and identify in half of the datasets significant dependence of the effects of stimulation on the phase at which stimulation is provided. The full nonlinear Wilson–Cowan model is fitted to datasets identified as statistically significant, and we show that in each case the model can fit to the dynamics of patient tremor as well as to the phase response curve. The vast majority of top fits are stable foci. The model provides satisfactory prediction of how patient tremor will react to phase-locked stimulation by predicting patient amplitude response curves although they were not explicitly fitted. We also approximate response curves of the significant datasets by providing analytical results for the linearisation of a stable focus model, a simplification of the Wilson–Cowan model in the stable focus regime. We report that the nonlinear Wilson–Cowan model is able to describe response to stimulation more precisely than the linearisation.

Temperature and phase dependences of Raman spectra (RS) and molecular relaxation characteristics of nitrate-ion vibrations in (1 – x)RbNO3 + xAl2O3 composites with various concentrations of Al2O3 nanopowder were studied. It was shown that the ν 1(A) vibrational relaxation time with filler concentration x = 0.6 was essentially constant in high-temperature phase RbNO3-II as compared with RbNO3-III, which indicated that the cubic RbNO3-III phase was stabilized. The salt subsystem was highly disordered at high filler concentrations so that structurally distinct states were difficult to detect at the macro level.

In the most conventional pulsed nuclear quadrupole resonance (NQR) systems, radio frequency (RF) pulses for irradiation are produced by chopping a continuous RF wave with a DC pulse. Therefore, RF pulses have phase coherency but NQR signals after each RF pulse have different initial phase. In this case, a phase-sensitive detection (PSD) using the same continuous RF wave is necessary to accumulate NQR signal. Meanwhile, recent improvement of device technology enables a phase controlled RF pulse and a direct sampling of NQR signal in the laboratory frame. We developed a new pulse NQR system using phase controlled RF pulse, in which RF pulses with the same initial phase are produced and NQR signal after each pulse is directly acquired in the laboratory frame, and then the accumulated signal is processed by digital quadrature detection and fast Fourier transform. This paper provides and compares the feature of NQR signals from both types of pulse NQR system. Main findings are that NQR signal obtained by a train of phase coherent pulses and PSD shows the periodical variation of the intensity depending on the offset frequency of the irradiation RF pulse from the resonance frequency but the signal obtained by the phase controlled RF pulse train does not. This feature would be important for the application of NQR to detection system for such as explosives.

Using the discrete dipole approximation (DDA) and a model of agglomerated debris particles, we study the contribution of large particles on the light scattering by cometary dust. The numerical simulations show that moderately and highly absorbing particles larger than 3 µm do not significantly affect the backscattering phenomena observed at visible wavelengths in comets at phase angles α ≤ 30°, such as the brightness surge and the negative polarization branch. Weakly and non-absorbing particles may play some role even if they are larger than 3 µm; but they are not abundant species in comets. However, the contribution of large particles on polarizations at phase angles α > 30° can be significant, even though they are highly absorbing; simultaneously, the phase dependence of brightness remains insensitive to the contribution of large particles.

We study the complexity of supergranular cells using the intensity patterns obtained from the Kodaikanal Solar Observatory during the 23rd solar cycle. Our data consists of visually identified supergranular cells, from which a fractal dimension D for supergranulation is obtained according to the relation P ∝ A D/2 ,w hereA is the area and P is the pe- rimeter of the supergranular cells. We find a difference in the fractal dimension between active and quiet region cells in the ascending phase, during the peak and in the descending phase which is conjectured to be due to the magnetic activity level.

This paper investigates the effects of the spontaneously generated coherence (SGC) and incoherent pumping field on the dynamical behaviors of the dispersion and the absorption. Using a three-level Λ-type atomic medium, the influence of the relative phase between the applied fields on the transient dispersion and absorption is discussed. It is shown that the phase dependence of the dispersion and the absorption not only depend on the existence of SGC, but they depend on the existence of the incoherent pumping field as well. We show that the medium can be used as an optical switch in which the propagation of the laser pulse can be controlled by another laser field.

We report here results from a study of X-ray bursts from 3 magnetar candidates (SGR 1806-20, SGR 1900+14 and AXP 1E 2259+586). We have searched for a pulse phase dependence of the X-ray burst rate from these sources. X-ray light curves were obtained with the Proportional Counter Array on-board the Rossi X-ray Timing Explorer during the periods of intense burst activity in these sources. On detailed analysis of the three sources, we found a very significant burst rate for all pulsar phases. However, some locations appear to produce bursts slightly more often, rendering the non-isotropic distribution. Only in the case of SGR 1900+14, there is a clear pulse phase dependence of burst rate.

We review the currently most accurate evaluation of the W boson mass, M_W, in the Minimal Supersymmetric Standard Model (MSSM). It consists of a full one-loop calculation, including the complex phase dependence, all available MSSM two-loop corrections as well as the full Standard Model result. We analyse the impact of the phases in the scalar quark sector on M_W and compare the prediction for M_W based on all known higher-order contributions with the experimental results.

We consider the tunneling of phonon excitations across a potential barrier spatially separating two condensates, which have different phases. We analyze the relation between the phase difference of two condensates and the coefficient of tunneling transmission by solving the Bogoliubov–de Gennes equations. As a resugt, the transmission coefficient T depends strongly on cp because of the y-dependent quasi-bound state.

It is shown that isolated hepatocytes are capable of perceiving slight changes in the envioronmental oxygen concentration. A complicated phase dependence exists between adenosine triphosphate and partial oxygen pressure, which differs in cells from animals with high and low resistance to hypoxia, the former showing a more stable and resistant energy-synthesizing function than the latter. After long-term adaptation to periodic hypoxia, the resistance of the energy-synthesizing function rises in hepatocytes from high-resistant animals, and falls in low-resistant animals suggesting a fundamentally different organization of the emergency compensatory mechanisms of the energy-synthesizing function in hepatocytes of animals of these two types.

Buspirone administered in the morning or evening completely suppressed the interspecies aggressiveness of isolated rats expressed as attacks on and bites of mice; muricidal behavior (killing of mice) was blocked by the drug only if it was administered in the evening. Electrolytic destruction of serotonin-containing structures of the midbrain levels the phase dependence of the antimuricidal properties of buspirone.

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.

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.

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.

BECAUSE of the favourable observing conditions, the planet Venus has frequently been observed in the radio spectrum for some years now. Recently, precise observations at the wave-length 3.3 cm were made by Bibikova et al.1. These observations were made after the inferior conjunction in Summer 1961. The authors found that the temperature of the planet was distinctly dependent on its phase. The mean temperature observed was about 544° K for the mean phase 0.47, and the value derived from the phase dependence for the inferior conjunction was found to be about 372° K. This large day–night contrast in temperature gives some support to Sagan's2 greenhouse model over Opik's3 aerospheric model of the Venusian atmosphere.