Miracle-dz/UniFAR-FTUs huggingface dataset:
Three supernova shells around a young M33 star cluster

Using a specialized technique sensitive to the presence of expanding ionized gas, we have detected a set of three concentric expanding shells in an HII region in the nearby spiral galaxy M33. After mapping the kinematics in Ha with Fabry-Perot spectroscopy, we used slit spectra to measure the intensities of the [S II] doublet at lambda lambda 671.9, 673.1 nm and the [N II] doublet at lambda lambda 645.8, 658.3 nm to corroborate the kinematics and apply diagnostic tests using line ratios. These showed that the expanding shells are shock dominated as would be the case if they had originated with supernova explosions. Estimating their kinetic energies, we find fairly low values, indicating a fairly advanced stage of evolution. We obtain density, mass and parent star mass estimates, which, along with the kinetic energies, are inconsistent with the simplest models of shock-interstellar medium interaction. We propose that the presence and properties of an inhomogeneous medium offer a scenario which can account for these observations, and discuss the implications. Comparing our results with data from the literature supports the combined presence of an H II region and supernova remnant material at the observed position.
A Splitter Theorem for 3-Connected 2-Polymatroids

Seymour's Splitter Theorem is a basic inductive tool for dealing with $3$-connected matroids. This paper proves a generalization of that theorem for the class of $2$-polymatroids. Such structures include matroids, and they model both sets of points and lines in a projective space and sets of edges in a graph. A series compression in such a structure is an analogue of contracting an edge of a graph that is in a series pair. A $2$-polymatroid $N$ is an s-minor of a $2$-polymatroid $M$ if $N$ can be obtained from $M$ by a sequence of contractions, series compressions, and dual-contractions, where the last are modified deletions. The main result proves that if $M$ and $N$ are $3$-connected $2$-polymatroids such that $N$ is an s-minor of $M$, then $M$ has a $3$-connected s-minor $M'$ that has an s-minor isomorphic to $N$ and has $|E(M)| - 1$ elements unless $M$ is a whirl or the cycle matroid of a wheel. In the exceptional case, such an $M'$ can be found with $|E(M)| - 2$ elements.
Moutard transform for the conductivity equation.

We construct Darboux-Moutard type transforms for the two-dimensional conductivity equation. This result continues our recent studies of Darboux-Moutard type transforms for generalized analytic functions. In addition, at least, some of the Darboux-Moutard type transforms of the present work admit direct extension to the conductivity equation in multidimensions. Relations to the Schrodinger equation at zero energy are also shown.
Ricci curvature bounds for weakly interacting Markov chains

We establish a general perturbative method to prove entropic Ricci curvature bounds for interacting stochastic particle systems. We apply this method to obtain curvature bounds in several examples, namely: Glauber dynamics for a class of spin systems including the Ising and Curie--Weiss models, a class of hard-core models and random walks on groups induced by a conjugacy invariant set of generators.
STEM Teaching and Learning in Rural Communities: Exploring Challenges and Opportunities

This special issue of Theory & Practice in Rural Education highlights STEM Teaching and Learning in Rural Communities. The articles selected represent both theory and practice and explore the complexities, practices, challenges, and opportunities facing rural schools and universities as they design and implement STEM teaching and learning. Articles from the field have related rural school success stories of how rural districts have overcome challenges to have effective and rich STEM teaching and learning in rural schools.
Disparity of clustering coefficients in the Holme‒Kim network model

Abstract The Holme‒Kim random graph process is a variant of the Barabási‒Álbert scale-free graph that was designed to exhibit clustering. In this paper we show that whether the model does indeed exhibit clustering depends on how we define the clustering coefficient. In fact, we find that the local clustering coefficient typically remains positive whereas global clustering tends to 0 at a slow rate. These and other results are proven via martingale techniques, such as Freedman's concentration inequality combined with a bootstrapping argument.
On the domain of elliptic operators defined in subsets of Wiener spaces

Let $X$ be a separable Banach space endowed with a non-degenerate centered Gaussian measure $\mu$. The associated Cameron-Martin space is denoted by $H$. Consider two sufficiently regular convex functions $U:X\rightarrow\mathbb{R}$ and $G:X\rightarrow \mathbb{R}$. We let $\nu=e^{-U}\mu$ and $\Omega=G^{-1}(-\infty,0]$. In this paper we are interested in the domain of the the self-adjoint operator associated with the quadratic form \begin{gather} (\psi,\varphi)\mapsto \int_\Omega\langle\nabla_H\psi,\nabla_H\varphi\rangle_Hd\nu\qquad\psi,\varphi\in W^{1,2}(\Omega,\nu). \qquad\qquad (\star) \end{gather} In particular we obtain a complete characterization of the Ornstein-Uhlenbeck operator on half-spaces, namely if $U\equiv 0$ and $G$ is an affine function, then the domain of the operator defined via $(\star)$ is the space \[\{u\in W^{2,2}(\Omega,\mu)\,|\, \langle\nabla_H u(x),\nabla_H G(x)\rangle_H=0\text{ for }\rho\text{-a.e. }x\in G^{-1}(0)\},\] where $\rho$ is the Feyel-de La Pradelle Hausdorff-Gauss surface measure.
Efficacy of Three Doses of Fungicide Ridomil Gold 66 WP in the Control of Phytophthora spp., Agent of Cocoa Tree Black Pod Disease in Côte d'Ivoire

Black pod disease is a major constraint to cocoa production in Côte d'Ivoire. Varietal selection and fungicide treatments are the principal means of control. Fungicide Ridomil Gold 66 WP (6% Metalaxyl and 60% copper oxide) is commonly used. This study aimed at evaluating the effectiveness of three doses of Ridomil Gold 66 WP in the control of black pod disease. An experiment on the rates of this fungicide was conducted in two localities (Aboisso and Duékoué). The experimental design was a randomized complete block with four treatments, replicated four times. The treatments comprised untreated or controlled, single dose (3.3 g/l) or recommended dose, double dose (6.6 g/l) or 2×recommanded dose and triple dose (9.9 g/l) or 3×recommanded dose. All data collected were subjected to ANOVA with the test of Student and Newmann-Keuls at the 5% threshold. As result, no significant difference was observed between the treatments of the three doses of Ridomil. But, a significant difference was observed between the fungicide treatments and the control. In Duékoué, black pod rates ranged from 4.5 to 9.52% in fungicide treated plots against 33.8% in control plots. In Aboisso, black pod rates ranged from 7.11 to 13.83% for fungicide treated plots against 30.83% for the control plots. Fungicide treatments increased healthy cocoa pod yields in both localities. The yields were increased by 51.35 to 89.63% in treated plots of Aboisso and by 34.63 to 101.06% in treated plots of Duékoué. This study confirmed the efficacy of the recommended dose (3.3 g/l) of Ridomil Gold 66 WP in the management of black pod disease. Yet, even if high doses of Ridomil Gold 66 WP improved yield, it could also be led to the development of resistant strains of Phytophthora spp. and increase production costs.
Ising Model on Twisted Lattice and Holographic RG flow

The partition function of the two-dimensional Ising model is exactly obtained on a lattice with a twisted boundary condition. The continuum limit of the model off the critical temperature is found to give the mass-deformed Ising conformal field theory (CFT) on the torus with the complex structure $\tau$. We find that the renormalization group (RG) flow of the mass parameter can be holographically described in terms of the three-dimensional gravity including a scalar field with a simple nonlinear kinetic function and a quadratic potential.
Constructing Sampling Schemes via Coupling: Markov Semigroups and Optimal Transport

In this paper we develop a general framework for constructing and analysing coupled Markov chain Monte Carlo samplers, allowing for both (possibly degenerate) diffusion and piecewise deterministic Markov processes. For many performance criteria of interest, including the asymptotic variance, the task of finding efficient couplings can be phrased in terms of problems related to optimal transport theory. We investigate general structural properties, proving a singularity theorem that has both geometric and probabilistic interpretations. Moreover, we show that those problems can often be solved approximately and support our findings with numerical experiments. For the particular objective of estimating the variance of a Bayesian posterior, our analysis suggests using novel techniques in the spirit of antithetic variates. Addressing the convergence to equilibrium of coupled processes we furthermore derive a modified Poincare inequality.
WKB analysis of edge states in graphene in a strong magnetic field

We investigate the fine structure of the edge states energy spectrum for zigzag and armchair ribbons of graphene in a strong magnetic field. At low energy, the spectra can be described by an effective Schrodinger Hamiltonian with a double well potential, symmetric in the zigzag case and asymmetric in the armchair case. We develop a semiclassical formalism based on the WKB approximation to calculate analytically the energy spectrum for the two types of edges, including regions which were not studied earlier. Our results are in very good quantitative agreement with numerical calculations. This approach leads to a qualitative description of the spectra in terms of the quantization of unusual classical orbits in the real space.
Stark units in positive characteristic

We show that the module of Stark units associated to a sign‐normalized rank one Drinfeld module can be obtained from Anderson's equivariant A ‐harmonic series. We apply this to obtain a class formula à la Taelman and to prove a several variable log‐algebraicity theorem, generalizing Anderson's log‐algebraicity theorem. We also give another proof of Anderson's log‐algebraicity theorem using shtukas and obtain various results concerning the module of Stark units for Drinfeld modules of arbitrary rank.
Financial Inclusion: Cost and Implications in Developing Countries: A Review of the Existing Literature

This article discusses about research reviews of financial inclusion comprehensively in terms of its nature, basic reasons behind financial exclusion, costs and implication of financial exclusion in developing country like Tanzania. The main objective of this study was to review and analyze various published articles related to financial inclusion in developing countries. The study specifically analyzed the extent to which the existing published academic articles have addressed the challenges associated with financial exclusion. Although substantial progress has been made, there is still much to achieve since FinScope survey Tanzania 2017 reports only 16.7% of adult population in Tanzania access to formal banking services. The same report maintains about 28% of adult Tanzanian are completely excluded from accessing financial services. Based on a content analysis, this study analyzed academic articles from demand side, supply side, regulatory and infrastructure and societal barriers. It is found that most developing countries and Tanzania in particular, are still faced by the mentioned challenges to effective financial inclusion. Lack of a clear and explicit policy on strategies toward inclusive finance and absence of explicit consumer protection regulation in Tanzania and other developing countries is yet another challenge. This study therefore suggests that, firstly, government and other stakeholders to establish guiding policy to enhancing financial inclusion efforts. Secondly, Policy makers and financial services providers need to initiate innovative infrastructure systems to enhance extension of financial services to rural areas at affordable operating costs. Thirdly, there is need for establishing and operationalizing consumer protection regulation among financial services providers. Finally, to encourage variety of financial providers, products and technologies to widen individuals and firms access to finance.
Black Holes and Photons with Entropic Force

Xiao-Gang He 2, 3, 4, ∗ and Bo-Qiang Ma 2, 4, † School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 Department of Physics and Center for Theoretical Sciences, National Taiwan University, Taipei 10617 Institute of Particle Physics and Cosmology, Department of Physics, Shanghai JiaoTong University, Shanghai 200240 Center for High-Energy Physics, Peking University, Beijing 100871
Integral representations of the star product corresponding to the s-ordering of the creation and annihilation operators

A new integral representation is obtained for the star product corresponding to the s-ordering of the creation and annihilation operators. This parametric ordering convention introduced by Cahill and Glauber enables one to vary the type of ordering in a continuous way from normal order to antinormal order. Our derivation of the corresponding integral representation is based on using reproducing formulas for analytic and antianalytic functions. We also discuss a different representation whose kernel is a generalized function and compare the properties of this kernel with those of the kernels of another family of star products which are intermediate between the qp ? > - and pq-quantization.
On Distinct Distances Between a Variety and a Point Set

We consider the problem of determining the number of distinct distances between two point sets in $\mathbb{R}^2$ where one point set $\mathcal{P}_1$ of size $m$ lies on a real algebraic curve of fixed degree $r$, and the other point set $\mathcal{P}_2$ of size $n$ is arbitrary. We prove that the number of distinct distances between the point sets, $D(\mathcal{P}_1,\mathcal{P}_2)$, satisfies\[D(\mathcal{P}_1,\mathcal{P}_2) = \begin{cases}\Omega(m^{1/2}n^{1/2}\log^{-1/2}n), \ \ & \mbox{ when } m = \Omega(n^{1/2}\log^{-1/3}n), \\\Omega(m^{1/3}n^{1/2}), \ \ & \mbox{ when } m=O(n^{1/2}\log^{-1/3}n). \end{cases}\]This generalizes work of Pohoata and Sheffer, and complements work of Pach and de Zeeuw.
Symmetry-preserving discretizations of arbitrary order on structured curvilinear grids

Mathematical descriptions of flow phenomena usually come in the form of partial differential equations. The differential operators used in these equations may have properties such as symmetry, skew-symmetry, positive or negative (definite)-ness. Symmetry-preserving methods are such that the discretized form of the continuous differential operator exhibits the same properties as the continuous operator itself. The use of symmetry-preserving discretizations makes it possible to construct discrete models which allow all the manipulations needed to prove stability and (discrete) conservation properties in the same way they were proven in the original continuous model. Furthermore, these methods allow a discretization of the continuous adjoint which is at the same time the discrete adjoint of the discrete forward model. Such adjoint models are not harder to code than the discrete forward model. This paper presents a new symmetry-preserving discretization of arbitrary order on curvilinear structured grids. The key idea is to use mutually-adjoint sampling and interpolation operators to switch between the continuous and discrete operator. The novelty of this work is that it combines three important requirements for discretizations: first, the symmetry-preserving discretization is made for arbitrary order of accuracy; second, the method works for every structured curvilinear mesh; and third, the method can be applied to every continuous operator. This paper is the first in a series of papers that gradually extends the theory to a general approach.
Construction of vacuum initial data by the conformally covariant split system

Using the implicit function theorem, we prove existence of solutions of the so-called conformally covariant split system on compact 3-dimensional Riemannian manifolds. They give rise to non-constant mean curvature (non-CMC) vacuum initial data for the Einstein equations. We investigate the conformally covariant split system defined on compact manifolds with or without boundaries. In the former case, the boundary corresponds to an apparent horizon in the constructed initial data. The case with a cosmological constant is then considered separately. Finally, to demonstrate the applicability of the conformal covariant split system in numerical studies, we provide numerical examples of solutions on manifolds and .
C∗–algebraic higher signatures and an
invariance theorem in codimension two

We revisit the construction of signature classes in C*-algebra K-theory, and develop a variation that allows us to prove equality of signature classes in some situations involving homotopy equivalences of noncompact manifolds that are only defined outside of a compact set. As an application, we prove a counterpart for signature classes of a codimension two vanishing theorem for the index of the Dirac operator on spin manifolds (the latter is due to Hanke, Pape and Schick, and is a development of well-known work of Gromov and Lawson).
Cultural influence on using mobile instant messaging applications to develop and maintain friendships

Abstract Mobile instant messaging (MIM) applications have gained popularity in recent years. Their useful and effective features help users communicate more effectively. Communication technology adoption requires an understanding of cultural factors. In this study, there are four cultural dimensions evaluated: collectivism (COL), masculinity (MAS), power distance (PWR), and uncertainty avoidance (UA). These four cultural dimensions of a country were studied in order to understand their relation to two constructs of friendship development (FD) and relationship management (RM). Furthermore, this study examines the relationship between those two constructs and people’s intentions to continue utilizing MIM. Three hundred and twenty-one respondents from Taiwan participated in an online survey. The PLS-SEM method was used to perform the data analysis. In the study, a significant correlation was found between collectivism and friendship development and relationship management. However, masculinity does not have a significant impact on friendship development. A high power distance does not negatively affect relationship management. A high power distance has a significant positive effect on relationship management. An increase in uncertainty avoidance does not negatively affect friendship development. However, an increase in uncertainty avoidance has a significant positive effect on friendship development. MIM apps for friendship development and relationship maintenance are impacted by four cultural dimensions. These findings provide theoretical and practical implications for insight into these factors.
Accelerating optimization-based computed tomography via sparse matrix approximations

Variational formulations of reconstruction in computed tomography have the notable drawback of requiring repeated evaluations of both the forward Radon transform and either its adjoint or an approximate inverse transform which are relatively expensive. We look at two methods for reducing the effect of this resulting computational bottleneck via approximating the transform evaluation with sparse matrix multiplications. The first method is applicable for general iterative optimization algorithms. The second is applicable in error-forgetting algorithms such as split Bregman. We demonstrate these approximations significantly reduce the needed computational time needed for the iterative algorithms needed to solve the reconstruction problem while still providing good reconstructions.
Creation and revival of ring dark solitons in an annular Bose–Einstein condensate

We propose a protocol for the simultaneous controlled creation of multiple concentric ring dark solitons in a toroidally trapped flat Bose–Einstein condensate. The decay of these solitons into a vortex–antivortex necklace shows revivals of the soliton structure, but eventually becomes an example of quantum turbulence.
The HI absorption "Zoo"

We present an analysis of the HI absorption in a sample of 101 flux-selected radio AGN (S_1.4 GHz > 50 mJy) observed with the Westerbork Synthesis Radio Telescope (WSRT). HI absorption is detected in 32 galaxies, showing a broad variety of widths, shapes and kinematical properties. We characterize the HI spectra of the individual detections using the busy function (Westmeier et al. 2014). With the goal of identifying different morphological structures of HI, we study the kinematical and radio source properties of the detections as function of their width. Narrow lines (FWHM < 100 km/s) mostly lie at the systemic velocity and are likely produced by regularly rotating HI disks or clouds. More HI disks can be present among galaxies with lines of intermediate widths (100 km/s < FWHM < 200 km/s), however the HI in these sources is more unsettled. We study the asymmetry parameter and blueshift/redshift distribution of the lines. We argue that if a profile is broad, it is also asymmetric and shifted relative to the systemic velocity because it is tracing unsettled HI gas. Besides three of the broadest (up to FW20 = 825 km/s) detections, which are associated with gas-rich mergers, we find three new cases of blueshifted broad wings (with FW20 >= 500 km/s). These detections are good candidates for being HI outflows. The detection rate of HI outflows is 5 percent in the total radio AGN sample. This fraction represents a lower limit, however it could suggests that, if outflows are a characteristic phenomenon of all radio sources, they would have a short depletion timescale compared to the lifetime of the AGN. Blueshifted and broad/asymmetric lines are more often present among young, compact sources, suggesting that in these AGN the HI is likely to be unsettled. This may arise due to jet-cloud interactions, as young radio sources clear their way through the rich ambient gaseous medium.
The more investigation of inflation and reheating stages based on the Planck and WMAP-9

The potential $V(\phi)=\lambda \phi^{n}$ is responsible for the inflation of the universe as scalar field $\phi$ oscillates quickly around some point where $V(\phi)$ has a minimum. The end of this stage has an important role on the further evolution stages of the universe. The created particles are responsible for reheating the universe at the end of this stage. The behaviour of the inflation and reheating stages are often known as power law expansion $S(\eta) \varpropto \eta^{1+\beta}$, $S(\eta) \varpropto \eta^{1+\beta_{s}}$ respectively. The reheating temperature ($T_{rh}$) and $\beta_{s}$ give us valuable information about the reheating stage. Recently people have studied about the behaviour of $T_{rh}$ based on slow-roll inflation and initial condition of quantum normalization. It is shown that there is some discrepancy on $T_{rh}$ due to amount of $\beta_{s}$ under the condition of slow-roll inflation and quantum normalization \cite{acq}. Therefore the author is believed in \cite{acq} that the quantum normalization may not be a good initial condition. But it seems that we can remove this discrepancy by determining the appropriate parameter $\beta_{s}$ and hence the obtained temperatures based on the calculated $\beta_{s}$ are in favour of both mentioned conditions. Then from given $\beta_{s}$, we can calculate $T_{rh}$, tensor to scalar ratio $r$ and parameters $\beta, n$ based on the Planck and WMAP-9 data. The observed results of $r, \beta_{s}, \beta$ and $n$ have consistency with their constrains. Also the results of $T_{rh}$ are in agreement with its general range and special range based on the DECIGO and BBO detectors.