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Open systems can only exist by self-organization as pulsing structures exchanging matter and energy with the outer world. This review is an attempt to reveal the organizational principles of the heterochromatin supra-intra-chromosomal network in terms of nonlinear thermodynamics. The accessibility of the linear information of the genetic code is regulated by constitutive heterochromatin (CHR) creating the positional information in a system of coordinates. These features include scale-free splitting-fusing of CHR with the boundary constraints of the nucleolus and nuclear envelope. The analysis of both the literature and our own data suggests a radial-concentric network as the main structural organization principle of CHR regulating transcriptional pulsing. The dynamic CHR network is likely created together with nucleolus-associated chromatin domains, while the alveoli of this network, including springy splicing speckles, are the pulsing transcription hubs. CHR contributes to this regulation due to the silencing position variegation effect, stickiness, and flexible rigidity determined by the positioning of nucleosomes. The whole system acts in concert with the elastic nuclear actomyosin network which also emerges by self-organization during the transcriptional pulsing process. We hypothesize that the the transcriptional pulsing, in turn, adjusts its frequency/amplitudes specified by topologically associating domains to the replication timing code that determines epigenetic differentiation memory.

This study is an attempt towards understanding the sources of long oscillations observed within the Pacific Ocean following the 11 March 2011 Tohoku earthquake. We present evidence that extremely long modes of the Pacific Ocean in the range of 2–48 h were excited by this giant tsunami. A numerical approach was employed to calculate the basin-wide modes of the Pacific Ocean, resulting in 49 modes in the range of 2–48 h. We studied 15 tide-gauge records around the Pacific Ocean in order to extract basin-wide modes of the Pacific Ocean excited by this transoceanic tsunami. Spectral analysis of these tide-gauge records showed that some of the calculated basin-wide modes were indeed excited by the Tohoku tsunami. The observed modes ranged from 2 to 49.8 h. We attributed the long oscillations of the Pacific Ocean during the 2011 Tohoku tsunami to the excitation of these basin-wide modes, which can be grouped into global modes (15–48 h) and regional modes (2–15 h). We classified the signals on the tide gauges into three groups: (1) basin-wide modes (>1.5 h), (2) the tsunami source periods (20–90 min), and (3) local bathymetric effects (<20 min). The average contributions to the total tsunami energy were 6.4 % for the basin-wide mode, 64.1 % for the tsunami source, and 29.5 % for the local bathymetry, although the ratios varied from station to station. Simulations suggest that the amount of contribution of basin effects to the total tsunami energy depends on the location of the tsunami source.

The real time W phase source inversion algorithm was independently running at three organizations (USGS, PTWC and IPGS) at the time of the 2011 off the Pacific coast of Tohoku Earthquake. Valuable results for tsunami warning purposes were obtained 20 min after the event origin time. Within the next hour, as more data became available, the W phase solutions improved, and converged to a common result ( M w ≈ 9.0, dip ≈ 14°). A post-mortem W phase analysis using data selection based on pre-event noise confirmed the M w = 9.0 result and yielded a best double couple given by (strike/dip/rake = 196°/12°/85°). We also ran the algorithm with increasingly longer periods ( T ≈ 1500 sec) to test for the possibility of additional slow slip. The seismic moment remained stable, confirming the prior results.

We propose that background Love and Rayleigh waves in a frequency range 5–20 mHz are generated primarily by ocean infragravity waves in the same frequency range by a linear coupling process with seafloor topography. Wavelengths of infragravity waves in this frequency range are on the order of 10 to 40 km in the deep ocean. The seafloor topography with wavelengths of this order is dominated by abyssal hills, which are the most widespread physiographic forms on Earth, covering as much as 85% of the Pacific floor. Interaction of infragravity waves in the deep ocean with these hills generates a random distribution of point‐like tangential forces on the seafloor which may be large enough to excite Love and Rayleigh waves simultaneously. We quantify this idea by using the known statistical property of hills distribution in the Pacific and by noting that heights of abyssal hills are an order of magnitude smaller than depths of the deep ocean, so that the topography‐related phase velocity change can be neglected. The model is reasonably consistent with the Love to Rayleigh wave amplitude ratio reported at 10–20 mHz and the observed background Rayleigh wave spectrum with a characteristic plateau around 8 mHz. Contribution of topographic coupling in shallow, coastal seas is not included in our simple model but should be important, especially at frequencies above 20 mHz.

We explore the Rayleigh-wave phase-velocity structure beneath northern Vietnam over a broad period range of 5 to 250 s. We use the two-stations technique to derive the dispersion curves from the waveforms of 798 teleseismic events recoded by a set of 23 broadband seismic stations deployed in northern Vietnam. These dispersion curves are then inverted for both isotropic and azimuthally anisotropic Rayleigh-wave phase-velocity maps in the frequency range of 10 to 50 s. Main findings include a crustal expression of the Red River Shear Zone and the Song Ma Fault. Northern Vietnam displays a northeast/southwest dichotomy in the lithosphere with fast velocities beneath the South China Block and slow velocities beneath the Simao Block and between the Red River Fault and the Song Da Fault. The anisotropy in the region is relatively simple, with a high amplitude and fast directions parallel to the Red River Shear Zone in the western part. In the eastern part, the amplitudes are generally smaller and the fast axis displays more variations with periods.

Ambient noise correlation has been successfully applied in several cases to regions with dense seismic networks whose geometries are well suited to tomographic imaging. The utility of ambient noise correlation‐based methods of seismic imaging where either network or noise field characteristics are less ideal has yet to be fully demonstrated. In this study, we focus on the Northland Peninsula of New Zealand using data from five seismographs deployed in a linear pattern parallel to the direction from which most of the ambient noise arrives. Shear wave velocity profiles computed from Rayleigh and Love wave dispersion curves using the Neighborhood Algorithm are in good agreement with the results of a previous active source refraction experiment and a teleseismic receiver function and surface wave analysis. In particular, we compute a path‐averaged Moho depth of ∼28 km along a ∼250 km profile. The use of both Rayleigh and Love wave measurements enables us to estimate the degree of radial anisotropy in the crust, yielding values of 2–15%. These results demonstrate that ambient noise correlation methods provide useful geophysical constraints on lithospheric structure even for nonoptimal network geometries and noise field characteristics.

We present the first detection of normal modes on Mars using the vertical records from InSight's broad‐band seismometer following the marsquake that occurred on sol 1222. The proposed catalog lists 60 potential eigenfrequencies between 3 and 12 mHz. Due to their low signal‐to‐noise ratio, these normal modes were detected using the phasor walkout approach. The normal modes amplitudes are consistent with the upper limit of the S1222a magnitude and with high quality factors. Additionally, we provide the first detection of a Martian hum before the quake for several of these frequencies. The proposed frequencies are at about 1‐sigma of those predicted by published models based on body wave travel time inversions. Our detection of normal modes is the first made on a terrestrial planet other than Earth and opens the way for future interior models that incorporate both normal modes frequencies, surface waves velocities and body wave travel times. Plain Language Summary The frequencies of a planet's global oscillations are closely linked to its internal structure. Thanks to the powerful magnitude 4.7 marsquake that occurred on sol 1222 and to the low long period noise of the very broad band Insight seismometer, we detected 60 normal mode frequencies. Furthermore, we discovered evidence of continuous vibrations on Mars, called Martian hum, as several eigenfrequencies were present before the marsquake occurred. Mars is now the second terrestrial planet after the Earth for which these planetary tones are observed. Key Points We present the first observational evidence of free oscillations excited by a seismic event and background oscillations on Mars We extracted normal modes hidden in low signal‐to‐noise ratio seismic record using a phasor walkout analysis Normal mode frequencies can be used to narrow down published Mars interior models obtained from body wave travel time inversions

GyPSuM is a 3‐D model of mantle shear wave (S) speeds, compressional wave (P) speeds, and density. The model is developed through simultaneous inversion of seismic body wave travel times (P and S) and geodynamic observations while using realistic mineral physics parameters linking wave speeds and density. Geodynamic observations include the global free air gravity field, divergence of the tectonic plates, dynamic topography of the free surface, and the flow‐induced excess ellipticity of the core‐mantle boundary. GyPSuM is built with the philosophy that heterogeneity that most closely resembles thermal variations is the simplest possible solution. Models of the density field from Earth's free oscillations have provided great insight into the density configuration of the mantle but are limited to very long wavelength solutions. Alternatively, scaling higher‐resolution seismic images to obtain density anomalies generates density fields that do not satisfy geodynamic observations. The current study provides a 3‐D density model for the mantle that directly satisfies geodynamic and seismic observations through a joint seismic‐geodynamic inversion process. Notable density field observations include high‐density piles at the base of superplume structures, supporting the general results of past normal mode studies. However, we find that these features are more localized and have lower amplitude than past studies would suggest. When we consider both fast and slow seismic anomalies in GyPSuM, we find that P and S wave speeds are strongly correlated throughout the mantle. However, we find a low correlation of fast S wave zones in the deep mantle (>1500 km depth) with the corresponding P wave anomalies, suggesting a systematic divergence from simplified thermal effects in ancient subducted slab anomalies. The cratonic lithosphere and D″ regions are shown to have strong compositional signatures. However, we argue that temperature variations are the primary cause of P wave speed, S wave speed, and density anomalies throughout most of the mantle.

We present observations of significant fundamental spheroidal‐toroidal mode coupling at frequencies below 4 mHz in the early part of vertical component records from seismic stations on near‐equatorial source‐receiver propagation paths after the 26 December 2004 and 28 March 2005 great Sumatra earthquakes. Since the mixed‐type coupling induced by rotational Coriolis force are very weak at these selected equatorial‐path stations, we investigate what effects mimic the strong Coriolis effects at frequencies below 4 mHz, suggesting that local azimuthal anisotropy in the upper mantle is the most likely explanation for the strong anomalous coupling we observed. In addition, strong anisotropy coupling observed in the frequency band of 1–4 mHz is always characterized by anomalous small amplitudes of coupled spheroidal modes on the vertical component of seismograph, suggesting that excitation of quasi‐toroidal modes by azimuthal anisotropy associates with geometric nodes of fundamental spheroidal modes.

The tidal and nontidal gravity change characteristics in the Tibetan Plateau region were investigated using the continuous gravity measurements recorded with a superconducting gravimeter (SG) installed in Lhasa from December 8, 2009 to September 30, 2011. The results indicated that the precision of the tidal gravity observations with the SG in Lhasa was very high. The standard deviation of the harmonic analysis for the gravity tides was 0.498 nm s-2, and the uncertainties of amplitude factors in the four main tidal waves (i.e., O1, K1, M2 and S2) were better than 0.002%. In addition, the diurnal gravity tide observations clearly revealed a pattern of nearly diurnal resonance. As a result, it is affirmed that the station should act as a local tidal gravity reference in the Tibetan Plateau and its adjacent regions. The load effects of oceanic tides are so weak that the resulting perturbation in the gravimetric factors is less than 0.6%. However, the load effects of the local atmosphere on either the tidal or the nontidal gravity observations are significant, although no seasonal variations have been found. After removing the atmospheric effects, the standard deviation of the harmonic analysis for the gravity tides decreased obviously from 4.160 to 0.498 nm s-2. Having removed the load effects of oceanic tides and local atmosphere, it is found that the tidal gravity observations are significantly different from those expected theoretically, which may be related to active tectonic movement and extremely thick crust in the Tibetan Plateau region. In addition, the Earth's free oscillations excited by 2011 Tohoku-Oki Mw 9.0 Earthquake were successfully detected.