Miracle-dz/UniFAR-FTUs huggingface dataset:
MRI channel flows in vertically stratified models of accretion discs

Simulations of the magnetorotational instability (MRI) in ‘unstratified’ shearing boxes exhibit powerful coherent flows, whereby the fluid vertically splits into countermoving planar jets or ‘channels’. Channel flows correspond to certain axisymmetric linear MRI modes, and their preponderance follows from the remarkable fact that they are approximate non-linear solutions of the MHD equations in the limit of weak magnetic fields. We show in this paper, analytically and with one-dimensional numerical simulations, that this property is also shared by certain axisymmetric MRI modes in vertically stratified shearing boxes. These channel flows rapidly capture significant amounts of magnetic and kinetic energy, and thus are vulnerable to secondary shear instabilities. We examine these parasites in the vertically stratified context, and estimate the maximum amplitudes that channels attain before they are destroyed. These estimates suggest that a dominant channel flow will usually drive the disc's magnetic field to thermal strengths. The prominence of these flows and their destruction place enormous demands on simulations, but channels in their initial stages also offer a useful check on numerical codes. These benchmarks are especially valuable given the increasing interest in the saturation of the stratified MRI. Lastly, we speculate on the potential connection between ‘run-away’ channel flows and outburst behaviour in protostellar and dwarf nova discs.
Dynamic memory network with spatial-temporal feature fusion for visual tracking

Abstract. Recently, single object tracking has demonstrated great success. However, due to various problems caused by fast motion, occlusion, and deformation, it is still intractable for traditional trackers to adapt to changes in object appearance. In this work, a dynamic memory network is proposed for visual tracking to handle the template matching process globally. More specifically, we first build a memory model, which consists of a memory feature fusion module and a memory bank. By the memory model, the network not only accepts the first frame as initial information but also memorizes the selective frames in the video sequence to provide rich time-domain information. Second, an innovative sampling strategy is adopted in the tracking process. By updating the template and guiding the selection of memory frames, our model can output higher-quality features. In addition, a spatial-channel fused attention module that effectively improves the representational capability and discriminability of the model is introduced. Our proposed method obtains compelling results on six challenging tracking benchmarks, including the OTB100, VOT2019, UAV123, NFS, GOT-10k, and LaSOT datasets. Extensive experiments demonstrate that our approach shows satisfactory robustness and leading application potential in real-time speed.
Membrane paradigm for Einstein-Gauss-Bonnet gravity

We construct the membrane paradigm for black objects in Einstein-Gauss-Bonnet gravity in spacetime dimensions ≥ 5. As in the case of general relativity, for the observers outside the horizon the dynamics of the perturbations of the horizon can be modelled as a membrane endowed with fluid-like properties. We derive the stress-tensor for this membrane fluid and study the perturbation around static backgrounds with constant curvature horizon cross-section to express the stress tensor in the form of a Newtonian viscous fluid with pressure, shear viscosity and bulk viscosity. The ratio of the shear viscosity and the entropy density is shown to generically violate the bound suggested by Policastro, Son and Starinets. We evaluate the transport coefficients for some static geometries. For the black brane geometry our results match with those available in the literature. For the spherically symmetric AdS black hole our results can be interpreted as a holographic prediction for the transport coefficients and viscosity to the entropy density ratio for the dual conformal field theory living on the boundary, S ×R. jacobson@umd.edu arif@phy.olemiss. edu sudipta@umd.edu
Targeting EZH2 Promotes Chemosensitivity of BCL-2 Inhibitor through Suppressing PI3K and c-KIT Signaling in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is one of the most common hematological malignancies with high heterogeneity, characterized by a differentiating block at the early progenitor stage. The selective BCL-2 inhibitor, Venetoclax (Ven), has shown exciting clinical results in a certain group of AML patients. However, Ven alone is insufficient to reach an enduringly complete response, which leads to the concern of Ven resistance. Alternative combined therapies with Ven are demanded in AML. Here, we reported the synergistic effect and molecular mechanism of the enhancer of zeste homolog 2 (EZH2) inhibitor DZNeP with Ven in AML cells. Results showed that the combination of DZNeP with Ven significantly induces cell proliferation arrest compared to single-drug control in AML cells and primary samples, and CalcuSyn analysis showed their significant synergy. The combination also significantly promotes apoptosis and increases the expression of pro-apoptotic proteins. The whole transcriptome analysis showed that phosphoinositide-3-kinase-interacting protein1 (PIK3IP1), the PI3K/AKT/mTOR signaling suppressor, is upregulated upon DZNeP treatment. Moreover, EZH2 is upregulated but PIK3IP1 is downregulated in 88 newly diagnosed AML cohorts compared to 70 healthy controls, and a higher expression of EZH2 is associated with poor outcomes in AML patients. Particularly, the combination of DZNeP with Ven dramatically eliminated CD117 (c-KIT) (+) AML blasts, suggesting the effect of the combination on tumor stem cells. In summary, our data indicated that DZNeP increases the sensitivity of Ven in AML by affecting PI3K and c-KIT signaling in AML. Our results also suggested that the therapeutic targeting of both EZH2 and BCL-2 provides a novel potential combined strategy against AML.
THE EXTREME ULTRAVIOLET DEFICIT AND MAGNETICALLY ARRESTED ACCRETION IN RADIO-LOUD QUASARS

The Hubble Space Telescope composite quasar spectra presented in Telfer et al. show a significant deficit of emission in the extreme ultraviolet for the radio-loud component of the quasar population (RLQs) compared to the radio-quiet component of the quasar population. The composite quasar continuum emission between 1100 Å and ∼580 Å is generally considered to be associated with the innermost regions of the accretion flow onto the central black hole. The deficit between 1100 Å and 580 Å in RLQs has a straightforward interpretation as a missing or a suppressed innermost region of local energy dissipation in the accretion flow. It is proposed that this can be the result of islands of large-scale magnetic flux in RLQs that are located close to the central black hole that remove energy from the accretion flow as Poynting flux (sometimes called magnetically arrested accretion). These magnetic islands are natural sites for launching relativistic jets. Based on the Telfer et al. data and the numerical simulations of accretion flows in Penna et al., the magnetic islands are concentrated between the event horizon and an outer boundary of <2.8 M (in geometrized units) for rapidly rotating black holes and <5.5 M for modestly rotating black holes.
Cross-lingual Transfer from Large Multilingual Translation Models to Unseen Under-resourced Languages

Low-resource machine translation has been a challenging problem to solve, with the lack of data being a big obstacle in producing good quality neural machine translation (NMT) systems. However, recent work on developing large multilingual translation models gives a platform for attempts to create NMT systems for extremely low-resource languages that can achieve reasonable and usable quality. We leverage the information in large multilingual translation models by performing cross-lingual transfer learning to extremely low-resource Finno-Ugric languages. Our experiments include seven languages with limited resources that are unseen by the original pre-trained translation model and five high-resource languages that have the potential to help during training, previously seen by the model during training. We report state-of-the-art results on multiple test sets and translation directions as well as analyze the low-resource languages in smaller language groups in order to track the source of our higher translation quality.
Light dark matter from the U(1)X sector in the NMSSM with gauge mediation

Cosmic ray anomalies observed by PAMELA and Fermi-LAT experiments may be interpreted by heavy (TeV-scale) dark matter annihilation enhanced by Sommerfeld effects mediated by a very light (sub-GeV) U(1)(X) gauge boson, while the recent direct searches from CoGeNT and DAMA/LIBRA experiments may indicate a rather light (similar to 7GeV) dark matter with weak interaction. Motivated by these apparently different scales, we consider a gauge mediated next-to-the minimal supersymmetric standard model (NMSSM) entended with a light U(1)(X) sector plus a heavy sector ((H) over barh, Hh), which can provide both a light (similar to 7GeV) and a heavy (TeV-scale) dark matter without introducing any ad hoc new scale. Through the Yukawa coupling between Hh and the messager fields, the U(1)(X) gauge symmetry is broken around the GeV scale radiatively and a large negative m(S)(2) is generated for the NMSSM singlet S. Furthermore, the small kinetic mixing parameter between U(1)(X) and U(1)(Y) is predicted to be theta similar to 10(-5) - 10(-6) after integrating out the messengers. Such a light dark matter, which can have a normal relic density from the late decay of the right-handed sneutrino (assumed to be the ordinary next-to-the lightest supersymmetric particle and thermally produced in the early Universe), can serve a good candidate to explain the recent CoGeNT and DAMA/LIBRA results.
Gene Expression of Sperm Associated Antigen 8 and Ran-Binding Protein 9 on Azoospermic Male : Its Association with Spermatogenic Arrest

Proteins that play an important role in the transcription process during spermatogenesis are CREMs that bind to their ACT activators that are suspected to be regulated by SPAG8 and RANBP9. Until now the role of both genes in the spermatogenic arrest process is not known. This study aims to determine the relative expression of Spag8 and RanBP9 on spermatogenic arrest and to analyze the correlation of expression of both genes. This study is a cross sectional study using a sample of testicular biopsy with Johnsen 2 to 8 score. Relative expression analysis of Spag8 and RanBP9 using qRT-PCR technique with Livak calculation. The data obtained were analyzed statistically using ANOVA one way test for Spag8 and Kruskal Wallis test for RanBP9 with significance value p <0,05. The results of this study show that the relative expression of Spag8 and RanBP9 is highest on Johnsen 3 scores and is statistically significantly different (p <0.05). There is a positive correlation with a very strong correlation strength between SPAG8 and RANBP9 expressions. Based on the results of this study shows that both of these genes are candidates for spermatogenic arrest.
The decay of turbulence generated by a class of multiscale grids

Abstract A new experimental investigation of decaying turbulence generated by a low-blockage space-filling fractal square grid is presented. We find agreement with previous works by Seoud & Vassilicos (Phys. Fluids, vol. 19, 2007, 105108) and Mazellier & Vassilicos (Phys. Fluids, vol. 22, 2010, 075101) but also extend the length of the assessed decay region and consolidate the results by repeating the experiments with different probes of increased spatial resolution. It is confirmed that this moderately high Reynolds number ${\mathit{Re}}_{\lambda } $ turbulence (up to ${\mathit{Re}}_{\lambda } \simeq 350$ here) does not follow the classical high Reynolds number scaling of the dissipation rate $\varepsilon \ensuremath{\sim} {u{}^{\ensuremath{\prime} } }^{3} / L$ and does not obey the equivalent proportionality between the Taylor-based Reynolds number ${\mathit{Re}}_{\lambda } $ and the ratio of integral scale $L$ to the Taylor microscale $\lambda $. Instead we observe an approximate proportionality between $L$ and $\lambda $ during decay. This non-classical behaviour is investigated by studying how the energy spectra evolve during decay and examining how well they can be described by self-preserving single-length-scale forms. A detailed study of homogeneity and isotropy is also presented which reveals the presence of transverse energy transport and pressure transport in the part of the turbulence decay region where we take data (even though previous studies found mean flow and turbulence intensity profiles to be approximately homogeneous in much of the decay region). The exceptionally fast turbulence decay observed in the part of the decay region where we take data is consistent with the non-classical behaviour of the dissipation rate. Measurements with a regular square mesh grid as well as comparisons with active-grid experiments by Mydlarski & Warhaft (J. Fluid Mech., vol. 320, 1996, pp. 331–368) and Kang, Chester & Meveneau (J. Fluid Mech., vol. 480, 2003, pp. 129–160) are also presented to highlight the similarities and differences between these turbulent flows and the turbulence generated by our fractal square grid.
Unusual strong-coupling effects in the tunneling spectroscopy of optimally doped and overdoped Bi2Sr2CaCu2O8+δ

Tunneling spectroscopy measurements are reported on single crystals of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} using vacuum tunneling and point-contact methods. A reproducible dip feature in the tunneling conductance is found near {vert_bar}eV{vert_bar}=2{Delta}, observed for {ital both} voltage polarities in the best resolved spectra. With overdoping the position of the dip continues to scale with {Delta}, and its magnitude decreases as {Delta} decreases. These results indicate that the dip feature arises from a strong-coupling effect whereby the quasiparticle lifetime is decreased at a characteristic energy of {approximately}2{Delta}, consistent with an electron-electron pairing interaction. {copyright} {ital 1997} {ital The American Physical Society}
Remark on orbital precession due to central-force perturbations

We show that the main result of the recent paper by G. S. Adkins and J. McDonnell, Phys. Rev. D 75, 082001 (2007), the formula for the precession of Keplerian orbits induced by central-force perturbations, can be obtained very simply by the use of Hamilton's vector.
Biological Activity of Extracts from Differently Produced Blueberry Fruits in Inhibiting Proliferation and Inducing Apoptosis of HT-29 Cells

For several decades, people have been searching for natural substances of plant origin that, when introduced into the diet, could strengthen immunity, have anticancer properties, and support conventional therapy. The development of agriculture with the implementation of various plant cultivation systems, apart from the economic aspect, results in the search for such cultivation conditions that would contribute to obtaining the most beneficial product for health. Therefore, the aim of our research is as follows: (a) to compare the antiproliferative activity and the ability to induce apoptosis of HT-29 cells by extracts from blueberry fruits deriving from different types of cultivation systems (conventional, organic, and biodynamic); (b) to examine whether the interaction of extracts with anticancer drugs used in the treatment of colorectal cancer is influenced by the type of cultivation, and (c) to investigate whether extracts obtained from fruits from subsequent years of cultivation retain the same biological activity. The results of our study are promising but inconclusive. A statistically significant difference occurred in only one of the two years of the study. The greatest inhibition of proliferation is observed for biodynamic cultivation compared to organic cultivation, while the highest levels of apoptosis and necrosis of HT-29 cells are induced by blueberry fruit extracts obtained from organic cultivation. The complementary effect of the extracts on the inhibition of HT-29 cell proliferation by anticancer drugs (5-FU and Erbitux) is not demonstrated. The induction of apoptosis by 5-FU is not enhanced by blueberry extracts, in contrast to necrosis. The level of apoptosis and necrosis induced by Erbitux is potentiated, but no dependence on crop type is shown. Blueberry fruit extracts from two consecutive years of cultivation did not maintain the same activity. A plausible reason for the variability in the composition and biological activity of fruit extracts obtained from two years of cultivation is the varying environmental conditions.
SPITZER PHASE CURVE CONSTRAINTS FOR WASP-43b AT 3.6 AND 4.5 μm

Previous measurements of heat redistribution efficiency (the ability to transport energy from a planet’s highly irradiated dayside to its eternally dark nightside) show considerable variation between exoplanets. Theoretical models predict a positive correlation between heat redistribution efficiency and temperature for tidally locked planets; however, recent Hubble Space Telescope (HST) WASP-43b spectroscopic phase curve results are inconsistent with current predictions. Using the Spitzer Space Telescope, we obtained a total of three phase curve observations of WASP-43b (P = 0.813 days) at 3.6 and 4.5 μm. The first 3.6 μm visit exhibits spurious nightside emission that requires invoking unphysical conditions in our cloud-free atmospheric retrievals. The two other visits exhibit strong day–night contrasts that are consistent with the HST data. To reconcile the departure from theoretical predictions, WASP-43b would need to have a high-altitude, nightside cloud/haze layer blocking its thermal emission. Clouds/hazes could be produced within the planet’s cool, nearly retrograde mid-latitude flows before dispersing across its nightside at high altitudes. Since mid-latitude flows only materialize in fast-rotating ( day) planets, this may explain an observed trend connecting measured day–night contrast with planet rotation rate that matches all current Spitzer phase curve results. Combining independent planetary emission measurements from multiple phases, we obtain a precise dayside hemisphere H2O abundance ( at 1σ confidence) and, assuming chemical equilibrium and a scaled solar abundance pattern, we derive a corresponding metallicity estimate that is consistent with being solar (0.4–1.7). Using the retrieved global CO+CO2 abundance under the same assumptions, we estimate a comparable metallicity of 0.3–1.7× solar. This is the first time that precise abundance and metallicity constraints have been determined from multiple molecular tracers for a transiting exoplanet.
Back to the Future: Estimating Initial Globular Cluster Masses from their Present Day Stellar Mass Functions

We use N-body simulations to model the 12 Gyr evolution of a suite of star clusters with identical initial stellar mass functions over a range of initial cluster masses, sizes, and orbits. Our models reproduce the distribution of present-day global stellar mass functions that is observed in the Milky Way globular cluster population. We find that the slope of a star cluster’s stellar mass function is strongly correlated with the fraction of mass that the cluster has lost, independent of the cluster’s initial mass, and nearly independent of its orbit and initial size. Thus, the mass function - initial mass relation can be used to determine a Galactic cluster’s initial total stellar mass, if the initial stellar mass function is known. We apply the mass function - initial mass relation presented here to determine the initial stellar masses of 33 Galactic globular clusters, assuming an universal Kroupa initial mass function. Our study suggests that globular clusters had initial masses that were on average a factor of 10 times larger than their present day mass, with seven clusters showing evidence for initial total stellar masses > 10 7 M⊙.
Constraints on warm dark matter models from high-redshift long gamma-ray bursts

Structures in Warm Dark Matter (WDM) models are exponentially suppressed below a certain scale, characterized by the dark matter particle mass, mx. Since structures form hierarchically, the presence of collapsed objects at high-redshifts can set strong lower limits on mx. We place robust constraints on mx using recent results from the Swift database of high-redshift gamma-ray bursts (GRBs). We parameterize the redshift evolution of the ratio between the cosmic GRB rate and star formation rate (SFR) as / (1+z) � , thereby allowing astrophysical uncertainties to partially mimic the cosmological suppression of structures in WDM models. Using a maximum likelihood estimator on two different z > 4 GRB subsamples (including two bursts at z > 8), we constrain mx & 1.6-1.8 keV at 95% CL, when marginalized over a flat prior in α. We further estimate that 5 years of a SVOM-like mission would tighten these constraints to mx & 2.3 keV. Our results show that GRBs are a powerful probe of high-redshift structures, providing robust and competitive constraints on mx.
Markov Processes linking Thermodynamics and Turbulence

This thesis deals with Markov processes in stochastic thermodynamics and fully developed turbulence. In the first part of the thesis, a detailed account on the theory of Markov processes is given, forming the mathematical fundament. In the course of developing the theory of continuous Markov processes, stochastic differential equations, the Fokker-Planck equation and Wiener path integrals are introduced and embedded into the class of discontinuous Markov processes. Special attention is paid to the difficulties that arise in the case of multiplicative noise. Referring to the paradigm of Brownian motion, the thermodynamic quantities work, heat and entropy, and the accompanied first law and second law, are formulated on the level of individual trajectories using stochastic differential equations. One of the prominent results of stochastic thermodynamics are so-called fluctuation theorems which reveal an intimate relation between entropy production and irreversibility. Using the path integral formulation, fluctuations theorems are derived in a formal setting. Applications of fluctuation theorems to thermodynamic systems are dependent on a reliable statistics of rare events. To access the statistics of rare events, an asymptotic method is developed. The first order asymptotics is derived for the general case of multiplicative noise, the second order asymptotics for the simpler case of additive noise. The application of the asymptotic method is demonstrated for work distributions in physically relevant models. The second part of the thesis carefully introduces the concept of fully developed turbulence and gives an account on established theories. These theories can be reformulated in terms of Markov processes. An overview of these Markov representations is compiled, including a few new approaches. In view of the results of stochastic thermodynamics, implications for the Markov representation are exploited. Fluctuation theorems are derived and applied to experimental data. In an experimental as well as theoretical analysis, fluctuation theorems are found to be sensitive to intermittent small-scale fluctuations. The above mentioned asymptotic method is used to assess these fluctuations. In closing the thesis, the discussed approaches to fully developed turbulence are contrasted with each other using their Markov representations, and an interpretation of the respective Markov processes is offered.