Miracle-dz/UniFAR-FTUs huggingface dataset:
Importance of the Access, Equity, and Opportunity Competencies Among 4-H Professionals

The 4-H Professional Research, Knowledge and Competencies (PRKC) is a professional development framework that can be used to identify competency gaps and training needs of 4-H professionals. The PRKC consists of 6 competency domains, 1 being access, equity, and opportunity (AEO). A tailored design method was used to gather data and sort the respondents between rural and urban community type. 4-H Extension agents serving urban communities perceived 12 out of the 14 AEO domain components as more important than agents serving rural communities did. The 2 AEO domain components that were not significantly different in perceived importance were values, norms, and practices and active listening. An essential element of the 4-H experience must include creating an environment where children and youth feel safe, included, and that they belong. The differences among 4-H youth development professionals’ perceptions of the importance of the AEO domain components, based on their work location, warrants further review. Implications of this information could influence the competencies that Extension systems look for in hiring. Furthermore, educational workshops and trainings around AEO for existing youth workers may need to be evolved.
Selection of Intermodal Conductivity Averaging Scheme for Unsaturated Flow in Homogeneous Media

The nonlinear solvers in numerical solution of water flow in variably saturated soils are prone to convergence difficulties. Many aspects can give rise to such difficulties, like very dry initial conditions, which causes a steep pressure gradient and great variation of hydraulic conductivity occurs across the wetting front during the infiltration of water. So, the averaging method applied to compute hydraulic conductivity between two adjacent nodes of the computational grid is one of the most important issues influencing the accuracy of the numerical solution of one-dimension al unsaturated flow equation i.e., Richards’ equation. A number of averaging schemes such as arithmetic, geometric, harmonic and arithmetic mean saturation have been proposed in the literature for homogeneous soil. The resulting numerical schemes are evaluated in terms of accuracy and computational time. It can be seen that the averaging scheme in the framework of arithmetic approaches favorably to other methods for a range of test cases.
A search for small solar-system bodies near the earth using a ground-based telescope - Technique and observations

A large, previously undetected flux of small bodies near earth is identified by employing the standard technique of detection of an individual object in two consecutive frames. The observational periods and viewing coordinates for the search for small bodies are presented. A null test is performed in order to further demonstrate that the signatures in the images are not due to instrumental artifacts. The observed fluxes, orbital motions, and radii of the small bodies detected are in agreement with those for the small cometlike objects previously reported. It is pointed out that the radii of the small bodies would be in the range of meters. Since an alternative interpretation of the small bodies is possible, it is suggested that the use of a telescope with larger aperture and/or array detectors with lesser noise levels is necessary to confirm the present observations.
Relativistic stars in f(R) gravity

We study the strong gravity regime in viable models of so-called f (R) gravity that account for the observed cosmic acceleration. In contrast with recent works suggesting that very relativistic stars might not exist in these models, we find numerical solutions corresponding to static star configurations with a strong gravitational field. The choice of the equation of state for the star is crucial for the existence of solutions. Indeed, if the pressure exceeds 3 times the energy density in a large part of the star, static configurations do not exist. In our analysis, we use a polytropic equation of state, which is not plagued with this problem and, moreover, provides a better approximation for a realistic neutron star.
AN EXTREMELY DEEP, WIDE-FIELD NEAR-INFRARED SURVEY: BRIGHT GALAXY COUNTS AND LOCAL LARGE SCALE STRUCTURE

We present a deep, wide-field near-infrared (NIR) survey over five widely separated fields at high Galactic latitude covering a total of ∼3 deg2 in J, H, and Ks. The deepest areas of the data (∼0.25 deg2) extend to a 5σ limiting magnitude of JHKs >24 in the AB magnitude system. Although depth and area vary from field to field, the overall depth and large area of this data set make it one of the deepest wide-field NIR imaging surveys to date. This paper discusses the observations, data reduction, and bright galaxy counts in these fields. We compare the slope of the bright galaxy counts with the Two Micron All Sky Survey and other counts from the literature and explore the relationship between slope and supergalactic latitude. The slope near the supergalactic equator is sub-Euclidean on average, pointing to the possibility of a decreasing average space density of galaxies by ∼10%–15% over scales of ∼250–350 Mpc. On the contrary, the slope at high supergalactic latitudes is strongly super-Euclidean on average, suggesting an increase in the space density of galaxies as one moves from the voids just above and below the supergalactic plane out to distances of ∼250–350 Mpc. These results suggest that local large scale structure could be responsible for large discrepancies in the measured slope between different studies in the past. In addition, the local universe away from the supergalactic plane appears to be underdense by ∼25%–100% relative to the space densities of a few hundred megaparsecs distant.
Handgrip strength and the risk of major depressive disorder: a two-sample Mendelian randomisation study

Background Major depressive disorder (MDD) is a common psychiatric disease and a leading cause of disability worldwide. Handgrip strength (HGS) as an objective physical fitness test is a practical index for identifying many diseases. Previous studies drew different conclusions about the relationship between HGS and MDD. Aims We aim to explore whether HGS has an effect on the risk of MDD. Methods HGS-related single-nucleotide polymorphisms identified by a genome-wide association study were used as instrumental variables in this Mendelian randomisation (MR) study. Summary data on MDD were obtained from the Psychiatric Genomics Consortium. Four methods were applied, including inverse variance weighted (IVW), MR Egger, weighted median and weighted mode. Additional sensitivity analyses, including leave-one-out, heterogeneity test, pleiotropy test and confounders identification, were conducted to test the robustness of our results. Results Each 1 kg increase in left HGS is associated with a 21.95% reduction in the risk of MDD (ORIVW = 0.781, 95% CI: 0.650 to 0.937, p=0.009), while no significant correlation exists in the estimation of right HGS (p=0.146). Sensitivity analyses demonstrated statistical significance (βIVW = −0.195, p=0.023) after excluding some genetic loci that cause pleiotropy. Conclusions Increased left HGS is associated with a reduced risk of MDD. In the future, it may be used as an index for the clinical screening, observation and treatment of MDD.
Magneto-Hydrodynamic Activity and Energetic Particles - Application to Beta Alfvén Eigenmodes.

The goal of magnetic fusion research is to extract the power released by fusion reactions and carried by the product of these reactions, liberated at energies of the order of a few MeV. The feasibility of fusion energy production relies on our ability to confine these energetic particles, while keeping the thermonuclear plasma in safe operating conditions. For that purpose, it is necessary to understand and find ways to control the interaction between energetic particles and the thermonuclear plasma. Reaching these two goals is the general motivation for the work conducted during the PhD. More specifically, our focus is on one type of instability, the Beta Alfven Eigenmode (BAE), which can be driven by energetic particles and impact on the confinement of both energetic and thermal particles. In this work, we study the characteristics of BAEs analytically and derive its dispersion relation and structure. Next, we analyze the linear stability of the mode in the presence of energetic particles. First, a purely linear description is used, which makes possible to get an analytical linear criterion for BAE destabilization in the presence of energetic particles. This criterion is compared with experiments conducted in the Tore-Supra tokamak during the PhD. Secondly, because the linear analysis reveals some features of the BAE stability which are subject to a strong non-linear modification, the question is raised of the possibility of a sub-critical activity of the mode. We propose a simple scenario which makes possible the existence of meta-stable modes, verified analytically and numerically. Such a scenario is found to be relevant to the physics and scales characterizing BAEs.
Environmental sustainability in Sub-Saharan Africa: Does information and communication technology (ICT) matter?

Abstract This study investigates the effect of information and communication technology (ICT) on environmental sustainability in 38 Sub-Saharan African (SSA) countries over a period 2000–2016. ICT is measured by internet penetration and mobile phone penetration whereas environmental sustainability is measured by CO2 emissions. The empirical evidence is based on the extended stochastic impact by regression on population, affluence and technology model. As estimation techniques, pooled ordinary least squares (OLS), fixed effect (FE), random effect (RE), panel correlated standard error (PCSE) and feasible generalised least squares (FGLS) are employed. The finding broadly shows that investment in ICT infrastructure enhances environmental sustainability. In addition, the effect of ICT is uniform across different income levels in SSA. As a policy implication, universal ICT access that encourages low pricing and broad coverage of equipment should be considered.
On dependence consistency of CoVaR and some other systemic risk measures

Abstract This paper is dedicated to the consistency of systemic risk measures with respect to stochastic dependence. It compares two alternative notions of Conditional Value-at-Risk (CoVaR) available in the current literature. These notions are both based on the conditional distribution of a random variable Y given a stress event for a random variable X , but they use different types of stress events. We derive representations of these alternative CoVaR notions in terms of copulas, study their general dependence consistency and compare their performance in several stochastic models. Our central finding is that conditioning on X ≥ VaR α ( X ) gives a much better response to dependence between X and Y than conditioning on X = VaR α ( X ). We prove general results that relate the dependence consistency of CoVaR using conditioning on X ≥ VaR α ( X ) to well established results on concordance ordering of multivariate distributions or their copulas. These results also apply to some other systemic risk measures, such as the Marginal Expected Shortfall (MES) and the Systemic Impact Index (SII). We provide counterexamples showing that CoVaR based on the stress event X = VaR α ( X ) is not dependence consistent. In particular, if ( X , Y ) is bivariate normal, then CoVaR based on X = VaR α ( X ) is not an increasing function of the correlation parameter. Similar issues arise in the bivariate t model and in the model with t margins and a Gumbel copula. In all these cases, CoVaR based on X ≥ VaR α ( X ) is an increasing function of the dependence parameter.
Evolution of the Far-Infrared-Radio Correlation and Infrared SEDs of Massive Galaxies over z = 0 - 2

We investigate the far-infrared-radio correlation (FRC) of stellar-mass-selected galaxies in the Extended Chandra Deep Field South using far-infrared imaging from Spitzer and radio imaging from the Very Large Array and Giant Metre-Wave Radio Telescope. We stack in redshift bins to probe galaxies below the noise and confusion limits. Radio fluxes are K-corrected using observed flux ratios, leading to tentative evidence for an evolution in spectral index. We compare spectral energy distribution (SED) templates of local galaxies for K-correcting FIR fluxes, and show that the data are best fit by a quiescent spiral template (M51) rather than a warm starburst (M82) or ULIRG (Arp220), implying a predominance of cold dust in massive galaxies at high redshift. In contrast we measure total infrared luminosities that are consistent with high star-formation rates. We observe that the FRC index (q) does not evolve significantly over z=0-2 when computed from K-corrected 24 or 160-mum photometry, but that using 70-mum fluxes leads to an apparent decline in q beyond z~1. This suggests some change in the SED at high redshift, either a steepening of the spectrum at rest-frame ~25-35mum or a deficiency at ~70mum leading to a drop in the total infrared/radio ratios. We compare our results to other work in the literature and find synergies with recent findings on the high-redshift FRC, high specific star-formation rates of massive galaxies and the cold dust temperatures in these galaxies.
Characterizing Risk Behaviour of Maize Farmers using the Experimental Gambling Approach: An Empirical Study in Ghana

Along the maize value chain in Ghana are a wide range of risks that confront actors; the risk chain actors' face include production and marketing risks. Accordingly, risk management, which has become an integral part of maize value chain activities, is challenged with several factors, some of which are economic, institutional, social and behavioral factors. This study posits that risk preferences/behavior of farm decision-makers in the maize value chain have empirical importance for economic and policy analysis. Thus, an experimental gambling approach was used to elicit the risk aversion behavior of respondents (farmers). Here, the respondents' risk aversion behavior over varying game levels was investigated. The multinomial logit model was used to investigate endogenous and exogenous factors explaining the risk behavior. The data were obtained by interviewing 220 maize farmers who were sampled with a two-stage sampling procedure. This study revealed that most of the farmers in the study area exhibited risk aversion behavior. About 33% of farmers showed extreme risk aversion behavior at the games’ lowest level and increased to 45% as the game level rose. It was also found that sex, age, level of formal education, access to credit, access to the storage facility, household size, farm size and the number of extension visits to the farm significantly explained the risk aversion behavior the maize farmers exhibited. Because farmers are risk-averse and become more risk-averse as stakes become high, any farm innovations to be introduced to them must be implemented gradually, especially with the low-income farmers. It is also critical to make risk mitigation 'handles' available to farmers so that they can rely on them during times of risk.
The role of stellar collisions for the formation of massive stars

We use direct N-body simulations of gas embedded star clusters to study the importance of stellar collisions for the formation and mass accretion history of high-mass stars. Our clusters start in virial equilibrium as a mix of gas and protostars. Protostars then accrete matter using different mass accretion rates and the amount of gas is reduced in the same way as the mass of stars increases. During the simulations we check for stellar collisions and we investigate the role of these collisions for the build-up of high-mass stars and the formation of runaway stars. We find that a significant number of collisions only occur in clusters with initial half-mass radii rh ≤ 0.1 pc. After emerging from their parental gas clouds, such clusters end up too compact compared to observed young, massive open clusters. In addition, collisions lead mainly to the formation of a single runaway star instead of the formation of many high-mass stars with a broad mass spectrum.We therefore conclude that massive stars formmainly by gas accretion, with stellar collisions only playing a minor role if any at all. Collisions of stars in the pre-main-sequence phase might, however, contribute to the formation of the most massive stars in the densest star clusters and possibly to the formation of intermediate-mass black holes with masses up to a few 100M.
Numerical simulation of turbulent sediment transport, from bed load to saltation

Sediment transport is studied as a function of the grain to fluid density ratio using two phase numerical simulations based on a discrete element method for particles coupled to a continuum Reynolds averaged description of hydrodynamics. At a density ratio close to unity (typically under water), vertical velocities are so small that sediment transport occurs in a thin layer at the surface of the static bed, and is called bed load. Steady, or “saturated” transport is reached when the fluid borne shear stress at the interface between the mobile grains and the static grains is reduced to its threshold value. The number of grains transported per unit surface is therefore limited by the flux of horizontal momentum towards the surface. However, the fluid velocity in the transport layer remains almost undisturbed so that the mean grain velocity scales with the shear velocity u*. At large density ratio (typically in air), the vertical velocities are large enough to make the transport layer wide and dilute. Sedime.
STAR-FORMING CLOUD COMPLEXES IN THE CENTRAL MOLECULAR ZONE OF NGC 253

We report 350 and 230 GHz observations of molecular gas and dust in the starburst nucleus of NGC 253 at 20–40 pc (1″–2″) resolution. The data contain CO(3–2), HCN(4–3), CO(2–1), 13CO(2–1), C18O(2–1), and continuum at 0.87 mm and 1.3 mm toward the central kiloparsec. The CO(2–1) size of the galaxy's central molecular zone (CMZ) is measured to be about 300 pc×100 pc at the half-maximum of intensity. Five clumps of dense and warm gas stand out in the CMZ at arcsecond resolution, and they are associated with compact radio sources due to recent massive star formation. They contribute one-third of the CO emission in the central 300 pc and have 12CO peak brightness temperatures around 50 K, molecular gas column densities on the order of 104 M☉ pc−2, gas masses on the order of 107 M☉ in the size scale of 20 pc, volume-averaged gas densities of cm−3, and high HCN-to-CO ratios suggestive of higher fractions of dense gas than in the surrounding environment. It is suggested that these are natal molecular cloud complexes of massive star formation. The CMZ of NGC 253 is also compared with that of our Galaxy in CO(2–1) at the same 20 pc resolution. Their overall gas distributions are strikingly similar. The five molecular cloud complexes appear to be akin to such molecular complexes as Sgr A, Sgr B2, Sgr C, and the l = 1. °3 cloud in the Galactic center. On the other hand, the starburst CMZ in NGC 253 has higher temperatures and higher surface (and presumably volume) densities than its non-starburst cousin.
COLLECTIVE PROPERTIES OF X-RAY BINARY POPULATIONS OF GALAXIES. I. LUMINOSITY AND ORBITAL PERIOD DISTRIBUTIONS OF HIGH-MASS X-RAY BINARIES

We introduce a method for obtaining the X-ray luminosity function (XLF) and the binary-period distribution of populations of high-mass X-ray binaries (HMXBs) in the stellar fields (i.e.,outside globular clusters) of normal galaxies. We start from standard distributions of the parameters of those primordial binaries which are the progenitors of HMXBs and follow the transformation of these distributions with the aid of a Jacobian formalism as the former evolve into the latter through the processes of the first mass transfer and the supernova (SN) that follows. We discuss the distributions of the post-SN binaries and the HMXBs. We show that our calculated model XLF has a differential slope ≈ − 1.6 with a flattening at low luminosities, in excellent agreement with observations. The calculated binary-period distribution, which basically has a slightly sloping plateau-like character at intermediate periods, with a rise to this plateau at shorter periods and fall-off from it at longer periods, is in agreement with the observed distribution within observational uncertainties. We discuss the physical origin of these distributions. We demonstrate that, while the effects of both (1) the distribution of the properties of the massive companion in the HMXBs and (2) the primordial orbital distribution and the SN dynamics are important, the former appear to be dominant in determining the XLF, and the latter in determining the HMXB binary-period distribution. We discuss the possible roles of stellar-mass black holes and ultraluminous X-ray sources in the observed “universal” XLF of HMXBs.
The galaxy population of Abell 1367: the stellar mass-metallicity relation

Using wide baseline broad-band photometry, we analyse the stellar population properties of a sample of 72 galaxies, spanning a wide range of stellar masses and morphological types, in the nearby spiral-rich and dynamically young galaxy cluster Abell 1367. The sample galaxies are distributed from the cluster centre out to approximately half the cluster Abell radius. The optical/near-infrared colours are compared with simple stellar population synthesis models from which the luminosity-weighted stellar population ages and metallicities are determined. The locus of the colours of elliptical galaxies traces a sequence of varying metallicity at a narrow range of luminosity-weighted stellar ages. Lenticular galaxies in the red sequence, however, exhibit a substantial spread of luminosity-weighted stellar metallicities and ages. For red-sequence lenticular galaxies and blue cloud galaxies, low-mass galaxies tend to be on average dominated by stellar populations of younger luminosity-weighted ages. Sample galaxies exhibit a strong correlation between integrated stellar mass and luminosity-weighted stellar metallicity. Galaxies with signs of morphological disturbance and ongoing star formation activity, tend to be underabundant with respect to passive galaxies in the red sequence of comparable stellar masses. We argue that this could be due to tidally driven gas flows towards the star-forming regions, carrying less enriched gas and diluting the pre-existing gas to produce younger stellar populations with lower metallicities than would be obtained prior to the interaction. Finally, we find no statistically significant evidence for changes in the luminosity-weighted ages and metallicities for either red-sequence or blue-cloud galaxies, at fixed stellar mass, with location within the cluster.
CAUSE OF SPIRAL GALAXY ROTATION RATES: A MASSIVE GRAVITON

We attribute the observed rotational velocity profiles of spiral galaxy disks to a combination of Newtonian and exponential gravitational potentials. We offer a novel, yet perfectly plausible, Lagrangian from which the exponential potential is derived. The exponential potential is defined by two universal constants (corresponding to a coupling constant and a graviton mass) that we determine from our sample of 12 THINGS disks. All velocity profile fits are excellent.