Miracle-dz/UniFAR-FTUs huggingface dataset:
A competition between heteroclinic cycles

Competition between co-existing heteroclinic cycles that have a common heteroclinic connection is considered. A simple model problem, consisting of a system of ordinary differential equations in R4 with Z24 symmetry, is analysed. The differential equations possess four hyperbolic fixed-points xi 1, xi 2, xi 3, and xi 4, with heteroclinic connections joining pairs of fixed points to form a 'heteroclinic network'. The network contains two heteroclinic cycles xi 1 to xi 2 to xi 3 to xi 1 and xi 1 to xi 2 to xi 4 to xi 1, each of which is structurally stable with respect to perturbations that preserve the Z24 symmetry of the problem. Local analysis, valid in the vicinity of the heteroclinic cycles, shows that while neither cycle can be asymptotically stable, there are conditions under which both cycles have strong attractivity properties simultaneously. For example, it is possible for both cycles to have the property that trajectories that pass through an open neighbourhood of one or more (but not all) of the heteroclinic connections in the given cycle are asymptotic to that cycle. The stability results depend on the strengths of the contracting and expanding eigenvalues of the flow linearized about each of the fixed points and on the validity of certain nondegeneracy conditions. The possible stability properties of the network and the cycles within it are determined.
Influence of Zinc and Humic Acids on Dye Adsorption from Water by Two Composts

Searching for alternative low-cost biosorbents for the removal of textile dyes from wastewater is currently an important subject of research. In this work, we have investigated how the presence of other contaminants in textile wastewaters can affect dye adsorption by biosorbents. We tested the adsorption of three dyes of different types: Basic Violet 10 (BV10), Acid Blue 113 (AB113) and Direct Blue 71 (DB71) by two different composts—municipal solid waste compost and pine bark compost—in the presence of Zn (5 mg L−1) or dissolved organic matter (100 mg humic acids L−1) in batch experiments. Dye adsorption capacity for both composts followed the following sequence: BV10 > AB113 > DB71. In general, dye sorption at the equilibrium was adequately described by the Freundlich model, but not always by the Langmuir model, which did not allow for the estimation of maximum retention capacities in all cases. In general, these were around 1 mg g−1 for DB71, 2 mg g−1 for AB113, and 40 mg g−1 for BV10. Municipal solid waste compost had slightly higher affinity than pine bark compost for the anionic dyes AB113 and DB71, whereas for the cationic dye BV10, pine bark compost presented a much higher adsorption capacity (41.7 mg g−1 versus 6.8 mg g−1). The presence of Zn or dissolved organic matter in the solutions at typical wastewater concentrations did not decrease the dye adsorption capacity of the composts. This result is positive both for the real application of composts to real textile wastewaters and for the validity of the results of biosorbent performance obtained with single-dye solutions.
Changes in UK parental mental health symptoms over 10 months of the COVID‐19 pandemic

Abstract Background The threats to health, associated restrictions and economic consequences of the COVID‐19 pandemic have been linked to increases in mental health difficulties for many. Parents, in particular, have experienced many challenges such as having to combine work with home‐schooling their children and other caring responsibilities. Yet, it remains unclear how parental mental health has changed throughout the pandemic or what factors may have mitigated or compounded the impact of the pandemic on parents' mental health. Methods We examined monthly survey data from two linked UK‐based longitudinal studies: COVID‐19: Supporting Parents, Adolescents and Children during Epidemics' (Co‐SPACE) and COVID‐19: Supporting Parents and Young Children during Epidemics' (Co‐SPYCE). Data from 5576 parents/carers of 2–17‐year‐old children collected between April 2020 and January 2021 was analysed using mixed‐effect modelling and latent class growth (mixture) modelling. Results Parental stress and depression, but not anxiety, were higher during the periods of restrictions. This pattern was most pronounced for parents with primary‐school‐aged children, those that worked at home or had other adults in the household. Being younger, reporting secondary or below education, working out of home, having secondary‐school‐aged children or children with special education needs (SEN)/neurodevelopmental disorders (ND) further moderated whether, how and when parental mental health symptoms changed. Although around three quarters of parents reported consistently low mental health symptoms, a substantial minority reported consistently high or increasing symptoms of anxiety, stress and depression. The latter were more likely to be parents who were younger than average, were a single adult in the household, had a pre‐existing mental health diagnosis or had a child with special educational needs or a ND. Conclusions These findings emphasise how different personal circumstances and pre‐existing inequalities shaped how parents were affected by this unprecedented global pandemic and highlight the need for support and consideration to meet the needs of families in the future.
Cubic autocatalytic reaction–diffusion equations: semi–analytical solutions

The Gray–Scott model of cubic–autocatalysis with linear decay is coupled with diffusion and considered in a one–dimensional reactor (a reaction–diffusion cell). The boundaries of the reactor are permeable, so diffusion occurs from external reservoirs that contain fixed concentrations of the reactant and catalyst. The Galerkin method is used to approximate the spatial structure of the reactant and autocatalyst concentrations in the reactor. Ordinary differential equations are then obtained as an approximation to the governing partial differential equations. The ordinary differential equations are then analysed to obtain semi–analytical results for the reaction–diffusion cell. Steady–state concentration profiles and bifurcation diagrams are obtained both explicitly, for the one–term method, and as the solution to a pair of transcendental equations, for the two–term method. Singularity theory is used to determine the regions of parameter space in which the four main types of bifurcation diagram occur. Also, in the semi–analytical model, a fifth bifurcation diagram occurs in an extremely small parameter region; its size being O(10–10). The region of parameter space, in which Hopf bifurcations can occur, is found by a local stability analysis of the semi–analytical model. An example of a stable limitcycle is also considered in detail. The usefulness and accuracy of the semi–analytical results are confirmed by comparison with numerical solutions of the governing partial differential equations.
TESTING FOR TREATMENT DEPENDENCE OF EFFECTS OF A CONTINUOUS TREATMENT

This paper provides nonparametric tests for hypotheses about the effects of a continuous treatment variable in a nonseparable structural equation. Specifically, we consider local average responses and average partial effects and test whether these effects are identical across different levels of treatment, including testing whether they are zero for all treatment levels as a special case. Our tests are based on consistent procedures of Bierens (1982, Journal of Econometrics 20, 105–134; 1990, Econometrica 58, 1443–1458) and Stinchcombe and White (1998, Econometric Theory 14, 295–324). The tests are easy to implement and achieve n-1/2 local power. Monte Carlo simulations show that the tests perform well in finite samples. We apply our tests to study the interest rate elasticities of loan demand in microfinance. We also extend our testing procedures to covariate-conditioned average effects and marginal effects.
On comparisons of sensitivity, specificity and predictive value of a number of diagnostic procedures.

Specificity (Q), senisitivity (Xq) and predictive value (p) have been proposed as measuies of the effectiveness of each of say t diagnostic procedures in the detection of a disease D (e.g., Thorner and Remein [1961]; Vecchio, [1966]). It is assumed that a definitive result can be obtained on the presence or absence of D in each of a series of n patients together with their diagnoses by the t procedures. In this paper x2 tests are developed for homogeneity of 7, 7, and p. These utilize matched sample x2 results of the author (Bennett [1967; 1968]).
Statistica Sinica Preprint No : SS-2016-0219 R 2 Title Simultaneous Confidence Bands in Nonlinear Regression Models with Nonstationarity

We consider nonparametric estimation of the regression function g(·) in a nonlinear regression model Yt = g(Xt)+σ(Xt)et, where the regressor (Xt) is a nonstationary unit root process and the error (et) is a sequence of independent and identically distributed (i.i.d.) random variables. With proper centering and scaling, the maximum deviation of the local linear estimator of the regression function g is shown to be asymptotically Gumbel. Based on the latter result, we construct simultaneous confidence bands for g, which can be used to test patterns of the regression function. Our results extend existing ones that typically require independent or stationary weakly dependent regressors. We examine the finite sample behavior of the proposed approach via simulated and empirical data examples.
A decade of amphibian studies (Animalia, Amphibia) at Sekayu lowland forest, Hulu Terengganu, Peninsular Malaysia

﻿Abstract Amphibians of Sekayu lowland forest have been studied more than a decade, with discoveries of new records of species showing no sign of abating between the years 2003 to 2020, indicating the remarkably rich diversity of anurans in this forest. Despite ceaseless anthropogenic activities in this area, this study successfully recorded 52 species of amphibians from 32 genera in the lowland forest of Sekayu. The species composition consisted of a single species from the family Ichthyophiidae and 51 species of anurans of 31 genera and six families. The number of species recorded has steadily increased especially during more recent surveys from 2015 to 2020. This study augments the total number of amphibian species recorded from Hulu Terengganu by ten additional species, increasing the total to 70 species for the district.
Damping numerical oscillations in hybrid solvers through detection of Gibbs phenomenon

A Gibbs phenomenon detector that is useful in damping numerical oscillations in hybrid solvers for compressible turbulence is proposed and tested. It is designed to function in regions away from discontinuities where commonly used discontinuity sensors are ineffective. Using this Gibbs phenomenon detector in addition to a discontinuity sensor for combining central and shock capturing schemes provides an integrated way of dealing with numerical oscillations generated by shock waves and contact lines that are normal to the flow. When complete suppression of numerical oscillations is not possible, they are sufficiently localized. Canonical tests and large eddy simulations show that inclusion of the proposed detector does not cause additional damping of ‘well‐resolved’ physical oscillations. Copyright © 2017 John Wiley & Sons, Ltd.
Afterburning and Combustion in Explosions in Barometric Calorimeters

The SDF charge construction is shown in Fig. 2. It begins with a 0.5-g spherical PETN booster (initial density of 1 g/cc). The booster is surrounded by fuel. For the composite charge, the fuel consists of 1.0-g spherical shell of TNT (initial density of 1.0 g/cc). For the Al-SDF charge, the booster is surrounded by a thin paper cylinder, and the void space is filled with 1.0-g of flake Aluminum (initial bulk density of 0.63 g/cc). SEM photographs of the Al powder indicates a flake-like structure of characteristic dimension 100 microns and a thickness of 1 micron. The booster is initiated by an exploding bridge wire located at the center of the charge.
Analysis of mechanical behaviour and internal stability of granular materials using discrete element method

Granular materials like sand are widely used in civil engineering. They are composed of different sizes of grains, which generate a complex behaviour, difficult to assess experimentally. Internal instability of a granular material is its inability to prevent the loss of its fine particles under flow effect. It is geometrically possible if the fine particles can migrate through the pores of the coarse soil matrix and results in a change in its mechanical properties. This paper uses the three‐dimensional Particle Flow Code (PFC3D/DEM) to study the stability/instability of granular materials and their mechanical behaviour after suffusion. Stability properties of widely graded materials are analysed by simulating the transport of smaller particles through the constrictions formed by the coarse particles under the effect of a downward flow with uniform pressure gradient. A sample made by an initially stable material according to the Kenney & Lau geometrical criterion was divided into five equal layers. The classification of these layers by this criterion before and after the test shows that even stable granular materials can lose fine particles and present local instability. The failure criterion of eroded samples, in which erosion is simulated by progressive removal of fine particles, evolves in an unexpected way. Internal friction angle increases with the initial porosity, the rate of lost fine particles and the average diameter D50. Copyright © 2016 John Wiley & Sons, Ltd.
Geostatistical delta-generalized linear mixed models improve precision for estimated abundance indices for West Coast groundfishes

James T. Thorson1*, Andrew O. Shelton2, Eric J. Ward2, and Hans J. Skaug3 Fisheries Resource Assessment and Monitoring Division (FRAM), Northwest Fisheries Science Center, National Marine Fisheries Service (NMFS), NOAA, 2725 Montlake Boulevard E, Seattle, WA 98112, USA Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service (NMFS), NOAA, 2725 Montlake Boulevard E, Seattle, WA 98112, USA Department of Mathematics, University of Bergen, PO Box 7800 5020 Bergen, Norway *Corresponding author: tel: +1 206 302 1772; fax: +1 206 860 6792; e-mail: James.Thorson@noaa.gov
VSOP polarization observations of the BL Lacertae object OJ 287

VLBI total intensity and linear polarization images of the BL Lacertae object OJ 287 have been obtained at using a global ground array and the HALCA orbiting antenna, and at two weeks earlier using the VLBA. In the ground-based 6-cm images, the source is dominated by a core–jet double structure the components of which are essentially unresolved. The baselines to the orbiting antenna resolve both of these compact components. In the VSOP images, the ground-based ‘core’ breaks up into several distinct components, demonstrating that this region is dominated by the contribution of bright, optically thin knots of jet emission. A very similar structure is observed in the 1.3-cm image. The magnetic field in the core is transverse, becomes longitudinal in the inner jet, then makes a sharp transition to a region of transverse field further from the core. This suggests that the field in the outer jet has become highly ordered in the transverse direction owing to the action of a shock; the physical nature of the extended region of longitudinal field closer to the core is not clear. The availability of nearly simultaneous observations with comparable resolution at widely spaced frequencies enabled detection of a ≃90° rotation in polarization position angle for the core, owing to the transition from the optically thick (6 cm) to the optically thin (1.3 cm) regime.
Comparative Analysis of Antioxidant System and Salt-Stress Tolerance in Two Hibiscus Cultivars Exposed to NaCl Toxicity

Hibiscus (Hibiscus syriacus L.) is known as a horticultural plant of great ornamental and medicinal value. However, the effect of NaCl stress on hibiscus seedlings is unclear. Little is known about H. syriacus ‘Duede Brabaul’ (DB) and H. syriacus ‘Blueberry Smoothie’ (BS). Here, the effects of solutions with different concentrations of NaCl on the organic osmolytes, ion accumulation, and antioxidant enzyme activity of hibiscus seedling leaves were determined. The results showed that the Na+/K+ ratio was imbalanced with increasing NaCl concentration, especially in BS (range 34% to 121%), which was more sensitive than DB (range 32% to 187%) under NaCl concentrations of 50 to 200 mM. To cope with the osmotic stress, the content of organic osmolytes increased significantly. Additionally, NaCl stress caused a large increase in O2·− and H2O2, and other reactive oxygen species (ROS), and antioxidant enzyme activity was significantly increased to remove excess ROS. The expression level of genes related to salt tolerance was significantly higher in DB than that in BS under different NaCl concentrations. Taken together, DB possessed a stronger tolerance to salt stress and the results suggest membrane stability, Na+/K+, H2O2, catalase and ascorbate peroxidase as salt tolerance biomarkers that can be used for gene transformation and breeding in future hibiscus research.
A restriction theorem for the Fourier transform

Jl/(0)ld0 = ƒƒ* f(x)fà(x)dx = fmdè*f(x)dx<\\f\\p\\âd *f\\p, for conjugate indices p and p . Thus it suffices to prove that the operator given by convolution with *3$ is bounded from LP to LP for p in the appropriate range. Let K(x) be a radial Schwartz function with K(x) = 1 for \x\ < 100, and let Tk(x) = [K(x/2 ) -K(xl2-)] $)(*). It suffices to show there exists e = e(p) > 0 such that \\Tk * ƒ \\p, < C2~ || ƒ ||p. This follows from interpolating the estimates \\Tk * ƒ IL < C2"~>*/|| f\\x and ||rfc *f\\2 < 2\\f\\2. Professor E. M. Stein has extended the range of this result to include p = 2(n + l)/(n + 3). His proof uses complex interpolation of the operators given by convolution with the functions Ba(x) = J0(27t\x\)/\x\°. Then
A low-noise monolithically integrated 1.5 Gb/s optical receiver in 0.6-/spl mu/m BiCMOS technology

Results of a monolithically integrated optical receiver for optical data transmission and optical interconnects is presented. A 0.6-/spl mu/m BiCMOS technology is used to realize the optoelectronic integrated circuit (OEIC). This OEIC can be used at data rates of 622 Mb/s, 1Gb/s, 1.25 Gb/s, and 1.5 Gb/s with a dual supply of 5 and 17 V with sensitivities of -24.5, -24.3, -24.1, and -22.1 dBm, respectively, at a bit-error rate of 10/sup -9/. With a single supply of 5 V, operation at 1.25 Gb/s with a sensitivity of -22.7 dBm was achieved.
Three-dimensional micromagnetic simulations of multidomain bubble-state excitation spectrum in ferromagnetic cylindrical nanodots

The excitation spectrum of multidomain bubble states in cylindrical nanodots with a large perpendicular anisotropy has been investigated by means of three-dimensional micromagnetic simulations for various dot diameters. In a first step, the evolution of the zero-field susceptibility spectra as a function of the dot diameter is studied for bidomain bubble states. Increasing dot diameter leads to shifts of the resonance frequencies toward the low frequencies for the fundamental domain wall and domain modes, whereas the spectral positions of surface domain wall and domain modes are weakly affected. Second, the high-frequency response of a tridomain bubble state stabilized in larger dot diameters is analyzed. Dynamic interaction effects are revealed mainly through the identification of coupled domain-wall modes, the resonance frequencies of which depend on the relative domain-wall chiralities. Lastly, the magnetization dynamics of a metastable bidomain bubble state with a pair of vertical Bloch lines, each of them possessing a Bloch point, is addressed. In such a case, the presence of magnetic singularities leads to a splitting of the fundamental domain-wall mode into two resonance lines assigned to oscillations of domain-wall parts with different phase relations.
Energy-level alignment at model interfaces of organic electroluminescent devices studied by UV photoemission: trend in the deviation from the traditional way of estimating the interfacial electronic structures

The electronic structures of model interfaces of organic electroluminescent (EL) devices were investigated with UV photoemission spectroscopy (UPS). Interfaces of TTN (tetrathianaphthacene) and TCNQ (tetracyanoquinodimethane) were also studied as extreme cases for hole transport and electron transport material, respectively. For all organic/metal interfaces studied, the work function of metal electrode was changed by deposition of organic layer, i.e., the vacuum level was shifted at the interface, indicating the invalidity of the traditional energy level alignment model where a common vacuum level was assumed at organic/metal interface. At TCNQ/Au, DP-NTCI/Al, which are acceptor/metal interfaces, upward shift of the vacuum level of organic layer relative to that of metal was observed, suggesting the formation of interfacial dipole due to electron-transfer from metal to acceptor. At other organic/metal interfaces, TPD(N, N'-diphenyl-N, N'-(3-methylphenyl)-1, 1'-biphenyl-4, 4'-diamine)/Au or ITO (indium tin oxide), ALq/sub 3/ (tris(8-hydroxyquinolino) aluminum)/Al, DP-NTCl(N, N'-diphenyl-1,4,5,8- naphthyltetracarboxylimide)/Al or Au, downward shift of the vacuum level was observed. Such downward shift has been also observed in our previous study for porphyrin/metal interfaces, and seems to be a trend for organic/metal interfaces at which no electron-transfer from metal to organic layer occurs. This trend suggests that the traditional model tends to underestimate (overestimate) the barrier height for hole (electron) injection. On the other hand, the vacuum level shift at ALq/sub 3//TPD interface was less than 0.1 eV, leading to an apparent applicability of the traditional model. However, it is not always the case for organic/organic interfaces: finite shift of 0.2 eV was observed at TTN/TCNQ interface due to electron-transfer from TTN to TCNQ. Possible origins of vacuum level shift at organic/metal interfaces were also discussed.
Effects of Flavonoids and Phenols from Moringa oleifera Leaf Extracts on Biofilm Processes in Xanthomonas campestris pv. campestris

Xanthomonas campestris pv. campestris is the causal agent of black rot in crucifers, a plant disease with significant economic impact. Xanthomonadaceae is a large family of Gram-negative bacteria that cause symptoms by blocking water flow in plants by invading the xylem. To accomplish this, the main mechanism the bacteria use to adapt to environmental changes and colonize tissues is biofilm formation. In recent years, growing interest in natural antimicrobial compounds has led to the study of different phytocomplexes derived from plants. In this work, Moringa oleifera was selected, as its leaves are rich in phenols, essential oils, and vitamins that exert antibacterial activity. X. campestris pv. campestris biofilm, one of its major virulence factors, was studied. Biofilm formation and removal were analyzed on abiotic and biotic surfaces with and without M. oleifera leaf extracts. The data from the analysis show that Moringa oleifera leaf extracts and single phenols were able to inhibit biofilm growth on abiotic surfaces, but the activity of the whole phytocomplex was significantly higher compared to that of individual phenols. The effect of Moringa oleifera extracts on cabbage leaves in vivo was also found to be very important, as scanning electron microscopy showed that treatment with the extracts led to clear unblocking of the xylem, implying many advantages for use in black rot control.