Miracle-dz/UniFAR-FTUs huggingface dataset:
Gravitational domain walls and the dynamics of $G$

From the point of view of elementary particle physics the gravitational constant G is extraordinarily small. This has led to ask whether it could have decayed to its present value from an initial one commensurate with microscopical units. A mechanism that leads to such a decay is proposed herein. It is based on assuming that G may take different values within regions of the universe separated by a novel kind of domain wall, a “G-wall”. The idea is implemented by introducing a gauge potential Aμνρ, and its conjugate D, which determines the value of G as an integration constant rather than a fundamental constant. The value of G jumps when one goes through a G-wall. The procedure extends one previously developed for the cosmological constant, but the generalization is far from straightforward: (i) The intrinsic geometry of a G-wall is not the same as seen from its two sides, because the second law of black hole thermodynamics mandates that the jump in G must cause a discontinuity in the scale of length. (ii) The size of the decay step in G is controlled by a function G(D) which may be chosen so as to diminish the value of G towards the asymptote G = 0, without fine tuning. It is shown that: (i) The dynamics of the gravitational field with G treated as a dynamical variable, coupled to G-walls and matter, follows from an action principle, which is given. (ii) A particle that impinges on a G-wall may be refracted or reflected. (iii) The various forces between two particles change when a G-wall is inserted in between them. (iv) G-walls may be nucleated trough tunneling and thermal effects. The semiclassical probabilities are evaluated. (v) If the action principle is constructed properly, the entropy of a black hole increases when the value of the gravitational constant is changed through the absorption of a G-wall by the hole.
An Overview of the Dwarf Galaxy Survey

The Dwarf Galaxy Survey (DGS) program is studying low-metallicity galaxies using 230 hr of far-infrared (FIR) and submillimetre (submm) photometric and spectroscopic observations of the Herschel Space Observatory and draws from this a rich database of a wide range of wavelengths tracing the dust, gas and stars. This sample of 50 galaxies includes the largest metallicity range achievable in the local Universe including the lowest metallicity ( Z) galaxies, 1/50 Z⊙, and spans four orders of magnitude in star formation rates. The survey is designed to get a handle on the physics of the interstellar medium (ISM) of low metallicity dwarf galaxies, especially their dust and gas properties and the ISM heating and cooling processes. The DGS produces PACS and SPIRE maps of low-metallicity galaxies observed at 70, 100, 160, 250, 350, and 500 μm with the highest sensitivity achievable to date in the FIR and submm. The FIR fine-structure lines, [CII] 158 μm, [OI] 63 μm, [OI] 145 μm, [OIII] 88 μm, [NIII] 57 μm, and [NII] 122 and 205 μm have also been observed with the aim of studying the gas cooling in the neutral and ionized phases. The SPIRE FTS observations include many CO lines ( J = 4–3 to J = 13–12), [NII] 205 μm, and [CI] lines at 370 and 609 μm. This paper describes the sample selection and global properties of the galaxies and the observing strategy as well as the vast ancillary database available to complement the Herschel observations. The scientific potential of the full DGS survey is described with some example results included.
Conjugate variables in quantum field theory and a refinement of Pauli's theorem

For the case of spin zero, we construct conjugate pairs of operators on Fock space. On states multiplied by polarization vectors, coordinate operators $Q$ conjugate to the momentum operators $P$ exist. In the massive case the notion of interest is derived from a geometrical quantity, the massless case is realized by taking the limit ${m}^{2}\ensuremath{\rightarrow}0$ on the one hand, on the other, starting with ${m}^{2}=0$ directly, from conformal transformations. The norm problem of the states on which the $Q$'s act is crucial: the states determine eventually how many independent conjugate pairs exist. It is intriguing that (light-) wedge variables and, hence, the wedge-local case seem to be preferred.
Morphological Alterations in Human Skeletal Muscle Cells Exposed to di-(2-Ethylhexyl) Phthalate (dehp) in Primary Cell Culture Conditions

Morphological alterations in human skeletal muscle cells exposed to di-(2-ethylhexyl) phthalate (dehp) in primary cell SUMMARY: Di-(2-ethylhexyl) phthalate (DEHP) is among the most common plasticizer additives that humans are in contact with daily. DEHP can be released from plastic and enter the human body, whereby it is metabolized and transformed into oxidative hydrophilic molecules. Clinical follow-ups in patients exposed to this phthalate and investigations in cultures of several cell types have provided information on its effects. For example, it is associated with inhibition of diploid human cell development and morphological changes in cultured germ cells. Although skeletal muscle represents around 50 % of the human body mass, knowledge about the effects of DEHP on this tissue is poor. Cultured skeletal muscle cells were exposed to DEHP (1 mM) for 13 days with the aim of exploring and evaluating some of the potential morphological effects. Three culture development parameters and nine cell characteristics were monitored during the bioassay. At 13 days, growth area, cell viability, and concentration of total proteins were lower in DEHP exposed than in control cells. Cell width and area, as well as the diameter of the nucleus and nucleolus, were greater in exposed cells than in control cells. These are interpreted as signs of cytotoxicity and suggest potential adverse effects on the development of skeletal muscle cells from DEHP exposure, as reported for other cell types.
Growth kinetics and morphological stability of precipitates in 3-D: a phase field study

We have studied the growth kinetics of isolated precipitates growing from a supersaturated matrix in 3-dimensions (3-D) using phase field models; we assume isotropic interfacial energy consider both constant and variable diffusivity. We report and compare our numerical growth rates with the classic analytical solutions of Zener and Frank (ZF). The numerical results deviate from the analytical ones. These deviations can be understood in terms of the generalised Gibbs-Thomson effect. Specifically, due to the higher capillary contribution in 3-D (curvature is twice for a sphere compared to a circle), the precipitate growth kinetics deviates more from ZF in 3-D as compared to 2-D. In addition, the kinetic parameter associated with the normal velocity of the precipitate-matrix interface also modifies the deviation of the precipitate composition from its equilibrium value and hence its growth kinetics. In phase field models (such as the one used by us) which use a combination of Allen-Cahn and Cahn-Hilliard type equations, we show how to choose the kinetic parameters (namely, mobility and relaxation parameter) so that the kinetic coefficient (in the generalised Gibbs-Thomson equation) is made effectively zero. We also show that the kinetic parameter the precipitate-matrix interface might play a crucial role in making the precipitate undergo morphological instabilities as it grows (leading to "sea-weed"-like structures).
Mimicking martingales

Given the univariate marginals of a real-valued, continuous-time martingale, (resp., a family of measures parameterised by t ∈ [ 0 ,T ] which is increasing in convex order, or a double continuum of call prices), we construct a family of pure-jump martingales which mimic that martingale (resp., are consistent with the family of measures, or call prices). As an example, we construct a fake Brownian motion. Then, under a further “dispersion” assumption, we construct the martingale which (within the family of martingales which are consistent with a given set of measures) has the smallest expected total variation. We also give a pathwise inequality, which in the mathematical ﬁnance context yields a model-independent sub-hedge for an exotic security with payoff equal to the total variation of the price process.
Supersymmetric resonant dark matter: A thermal model for the AMS-02 positron excess

We construct a thermal dark matter model with annihilation mediated by a resonance to explain the positron excess observed by PAMELA, Fermi-LAT and AMS-02, while satisfying constraints from cosmic microwave background (CMB) measurements. The challenging requirement is that the resonance has twice the dark matter mass to one part in a million. We achieve this by introducing an $SU(3)_f$ dark flavor symmetry that is spontaneously broken to $SU(2)_f \times U(1)_f$. The resonance is the heaviest state in the dark matter flavor multiplet and the required mass relation is protected by the vacuum structure and supersymmetry from radiative corrections. The pseudo-Nambu Goldstone Bosons (PNGB's) from the dark flavor symmetry breaking can be slightly lighter than one GeV and dominantly decay into two muons just from kinematics, with subsequent decay into positrons. The PNGB's are produced in resonant dark matter semi-annihilation, where two dark matter particles annihilate into an anti-dark matter particle and a PNGB. The dark matter mass in our model is constrained to be below around 1.9 TeV from fitting thermal relic abundance, AMS-02 data and CMB constraints. The superpartners of Standard Model (SM) particles can cascade decay into a light PNGB along with SM particles, yielding a correlated signal of this model at colliders. One of the interesting signatures is a resonance of a SM Higgs boson plus two collimated muons, which has superb discovery potential at LHC Run 2.
Global Forty-Years Validation of Seasonal Precipitation Forecasts: Assessing El Ni\~no-Driven Skill

The skill of seasonal precipitation forecasts is assessed worldwide —grid point by grid point— for the forty-years period 1961-2000. To this aim, the ENSEMBLES multimodel hindcast is considered. Although predictability varies with region, season and leadtime, results indicate that 1) significant skill is mainly located in the tropics —20 to 40% of the total land areas—, 2) overall, SON (MAM) is the most (less) skillful season and 3) predictability does not decrease noticeably from one to four months lead-time —this is so especially in northern south America and the Malay archipelago, which seem to be the most skillful regions of the world—. An analysis of teleconnections revealed that most of the skillful zones exhibit significant teleconnections with El Niño. Furthermore, models are shown to reproduce similar teleconnection patterns to those observed, especially in SON —with spatial correlations of around 0.6 in the tropics—. Moreover, these correlations are systematically higher for the skillful areas. Our results indicate that the skill found might be determined to a great extent by the models’ ability to properly reproduce the observed El Niño teleconnections, i.e., the better a model simulates the El Niño teleconnections, the higher its performance is.
An Archive of Spectra from the Mayall Fourier Transform Spectrometer at Kitt Peak

We describe the SpArc science gateway for spectral data obtained using the Fourier Transform Spectrometer (FTS) in operation at the Mayall 4-m telescope at the Kitt Peak National Observatory during the period from 1975 through 1995. SpArc is hosted by Indiana University Bloomington and is available for public access. The archive includes nearly 10,000 individual spectra of more than 800 different astronomical sources including stars, nebulae, galaxies, and solar system objects. We briefly describe the FTS instrument itself and summarize the conversion of the original interferograms into spectral data and the process for recovering the data into FITS files. The architecture of the archive is discussed and the process for retrieving data from the archive is introduced. Sample use cases showing typical FTS spectra are presented.
Td-MoTe2: A possible topological superconductor

We measured the magnetoresistivity properties of Td-MoTe2 single crystal under the magnetic field up to 33 T. By analyzing the Shubnikov–de Haas oscillations of the longitudinal resistance Δρxx, a linear dependence of the Landau index n on 1/B is obtained. The intercept of the Landau index plot is 0.47, which is between 3/8 and 1/2. This clearly reveals a nontrivial π Berry's phase, which is a distinguished feature of the surface state in Td-MoTe2 single crystal. Accompanied by the superconductivity observed at TC = 0.1 K, Td-MoTe2 may be a promising candidate of the topological superconductor and opens a door to study the relationship between the superconductivity and topological physics.
Effect of Tea Infusion Strength on Equivalent Circuit Parameters of Multielectrode Voltammetric Sensor System

Analysis of voltammetric response obtained from black tea liquor samples has been used extensively in research to evaluate tea quality. The recent system identification-based quality estimation method of black tea uses the equivalent circuit parameters of the voltammetric system. This work reports the analysis of these equivalent circuit parameters of a multielectrode voltammetric system in correlation with the change in concentration of black tea liquor. In this work, the experimental input–output data obtained using the voltammetric analysis of tea liquor is subjected to the system identification to obtain the system process model. The model hence obtained is subjected to a network synthesis procedure to estimate the equivalent circuit parameters of the system with various electrodes and at different concentrations of tea samples. Therefore, the tea infusion strength is simulated by varying concentrations. The performance parameters of the models identified for all the electrode–analyte combinations are calculated by comparing the experimental and the simulated waveforms. The study of the concentration of tea samples and circuit parameters agrees with the theoretical concepts. This work therefore also provides a legitimate validation to the established equivalent circuit for the voltammetric taste measurement system (electronic tongue). The cluster analysis performed here reveals a potential application of this work in the domain of electronic tongue.
An analysis: different methods about line art colorization

We have conducted a series of studies and analyses to address the problem of line art colorization. We chose Generative Adversarial Networks (GANs), a leading neural network architecture for solving this problem, as our focus. For a large number of studies based on this architecture, we improved, applied, and analytically compared four methods, pix2pix, pix2pixHD, white-box, and scaled Fourier transform (SCFT), which can represent the mainstream problem-solving direction in the field of line colorization to the greatest extent possible. Finally, two reference quantities were introduced to quantify the results of the analysis.
Sistema multi-robot de manipuladores industriales coordinados por acoplamientos dinámicos de segundo orden

En este trabajo se presenta el desarrollo de un sistema coordinado conformado por dos robots industriales de la marca ABB equipados con sensores de fuerza. Sistema cuya funcion es la sujeción y manipulación de objetos utilizando un contacto puntual. Al ser un sistema coordinado ambos robots tienen acceso a toda la informacion de su fuerza aplicada, ruta deseada del objeto y posicion del efector final del otro robot, a diferencia de un sistema maestro-esclavo donde solamente uno posee la información. Se implementan tres esquemas de control: control de fuerza-par, el cual permite regular la penetracion generada por el contacto en el objeto, el otro un control de posicion del objeto, el cual tiene como función cambiar la referencia de fuerza para que con este diferencial se produzca la manipulacion del objeto, y un control por acoplamiento, cuya función es aumentar o disminuir la referencia de fuerza, para que los efectores finales siempre se encuentren a la misma distancia (desde ahora denominada distancia de agarre) y se asegure un agarre estable del objeto. Se presentan pruebas experimentales de dos tipos: el primero siendo el sistemasin el control por acoplamiento para ver la variacion de la distancia de agarre y como fluctúa al momento de realizar el movimiento horizontal del objeto. Y el segundo, el sistema totalmente integrado donde se comprueba si el control disminuye esa fluctuacion y se logra mantener constante la distancia de agarre.
An analysis of stakeholders’ support mechanism for the preservation of weaving in an indigenous community

With the fast influence of modernization, many people have to adapt to meet the demand of the changes in society, including the indigenous communities. Some parts of their culture are being at risk due to the high call of alteration. In these communities, customs and traditions should be protected to preserve their culture, heritage, and their identity as a tribe. Thus, the purpose of the study was to make an analysis of stakeholders’ support mechanism for the preservation of weaving in an indigenous community. The research design of the study followed the quantitative research design complemented with qualitative data to analyze the stakeholders’ support mechanisms. Quantitative data were analyzed with the application of the Prince Chart and Prince Method of Calculation, while qualitative data were perused through content or textual analysis. The research participants of the study were the thirty (30) respondents who answered the survey questionnaire adopted from the UP-NCPAG, and ten (10) informants who went through an in-depth interview (IDI). The results of the quantitative data analysis showed that the issue position elicited affirmative score, while the power and priority scored high. It also showed a 100% probability of support from the stakeholders, which denotes certainty of implementation. On the other hand, the qualitative data and findings reinforced and validated the quantitative data and findings. The study arrived at a conclusion that there is high optimism and likelihood that the proposed development of NC II Weaving in Amgu-o will become a reality which will lead to the preservation of weaving the indigenous community.
Boundary Value Problems for the Helmholtz Equation for a Half-plane with a Lipschitz Inclusion

This paper considers to the problems of diffraction of electromagnetic waves on a half-plane, which has a finite inclusion in the form of a Lipschitz curve. The diffraction problem formulated as boundary value problem for Helmholtz equations and boundary conditions Dirichlet or Neumann on the boundary, as well as the radiation conditions at infinity. We carry out research on these problems in generalized Sobolev spaces. We use the operators of potential type, that by their properties are analogs of the classical potentials of single and double layers. We proved the solvability of the boundary value problems of Dirichlet and Neumann. We have obtained solutions of boundary value problems in the form of operators of potential type. Boundary problems are reduced to integral equations of the second kind.
EVIDENCE FOR INFLOW IN HIGH-MASS STAR-FORMING CLUMPS

We analyze the HCO+ 3–2 and H13CO+ 3–2 line profiles of 27 high-mass star-forming regions to identify asymmetries that are suggestive of mass inflow. Three quantitative measures of line asymmetry are used to indicate whether a line profile is blue, red, or neither—the ratio of the temperature of the blue and red peaks, the line skew, and the dimensionless parameter δv. We find nine HCO+ 3–2 line profiles with a significant blue asymmetry and four with significant red asymmetric profiles. Comparing our HCO+ 3–2 results to HCN 3–2 observations from Wu et al., we find that eight of the blue and three of the red have profiles with the same asymmetry in HCN. The eight sources with blue asymmetries in both tracers are considered strong candidates for inflow. Quantitative measures of the asymmetry (e.g., δv) tend to be larger for HCN. This, combined with possible HCO+ abundance enhancements in outflows, suggests that HCN may be a better tracer of inflow. Understanding the behavior of common molecular tracers like HCO+ in clumps of different masses is important for properly analyzing the line profiles seen in a sample of sources representing a broad range of clump masses. Such studies will soon be possible with the large number of sources with possible self-absorption seen in spectroscopic follow-up observations of clumps identified in the Bolocam Galactic Plane Survey.
Dynamics of non-Markovian open quantum systems

Open quantum systems (OQSs) cannot always be described with the Markov approximation, which requires a large separation of system and environment time scales. An overview is given of some of the most important techniques available to tackle the dynamics of an OQS beyond the Markov approximation. Some of these techniques, such as master equations, Heisenberg equations, and stochastic methods, are based on solving the reduced OQS dynamics, while others, such as path integral Monte Carlo or chain mapping approaches, are based on solving the dynamics of the full system. The physical interpretation and derivation of the various approaches are emphasized, how they are connected is explored, and how different methods may be suitable for solving different problems is examined.
Correlation between lithium abundances and ages of solar twin stars

We want to determine the lithium abundances of solar twin stars as a function of stellar age to provide constraints for stellar evolutions models and to investigate whether there is a connection between low Li abundance and the occurrence of planets. For a sample of 21 solar twins observed with the HARPS spectrograph at high spectral resolution (R~115.000) and very high signal-to-noise ratio (600 < S/N < 2400), precise lithium abundances were obtained by spectral synthesis of the LiI 6707.8 A line and compared to stellar ages, masses, and metallicities determined from a spectroscopic analysis of the same set of HARPS spectra. We show that for the large majority of the solar twins there is a strong correlation between lithium abundance and stellar age. As the age increases from 1 to 9 Gyr, the Li abundance decreases by a factor of ~ 50. The relation agrees fairly well with predictions from non-standard stellar evolution models of Li destruction at the bottom of the upper convection zone. Two stars deviate from the relation by having Li abundances enhanced by a factor of ~ 10, which may be due to planet engulfment. On the other hand, we find no indication of a link between planet hosting stars and enhanced lithium depletion.