Miracle-dz/UniFAR-FTUs huggingface dataset:
Persistence and stability analysis of discrete-time predator–prey models: a study of population and evolutionary dynamics

ABSTRACT Prolonged exposure to disturbances, such as toxicants, has the potential to result in evolutionary responses in a population. These evolutionary responses may impact not just that species but also other species with which the population interacts. In this paper, we develop a discrete-time predator–prey model and establish conditions for the existence and stability of equilibria, as well as conditions for the persistence of the prey and predator populations. We then extend this model to an evolutionary model which couples the population dynamics with the dynamics of an evolving phenotypic trait that provides a measure for the level of toxicant resistance developed by the prey. We study the persistence dynamics of this model and establish conditions for when the prey evolves toxicant resistance. We show that the evolution of toxicant resistance may allow both the predator and prey to persist when, without the evolution, both may go extinct.
DETERMINATION OF THE GROSS ALPHA AND BETA ACTIVITY CONCENTRATIONS IN SOME SELECTED CHILDREN’S DIET IN SABO, KADUNA STATE

Twenty samples of different food brands produced locally and internationally that are commonly consumed by children were collected from the local markets in Sabo local government area of Kaduna state and analyzed using a gas proportional counter to determine the gross alpha and beta activity concentration. The results obtained showed that the average gross alpha and beta activity for the children’s diet sample was 180 Bqkg -1 and 240 Bqkg -1 respectively. These results revealed high alpha activity of eight food samples as they were above the World Health Organization (WHO) standard of 100 Bqkg -1 while for beta activity, all food samples analyzed were below the WHO standard limit of 1000 Bqkg -1 . However, the results so obtained, may not pose any immediate health side effects to children consuming these product as further analysis of the specific activity is recommended.
Improving Access to Psychological Therapies (IAPT) Programme: Setting Key Performance Indicators in a More Robust Context: A New Perspective

The key performance indicators (KPIs) for the Improving Access to Psychological Therapies (IAPT) programme as published by the Department of Health (DH) use patients “completing treatment” as a denominator for calculating rates of “moving to recovery”. The implications of applying different denominators to the indicator “moving to recovery” were explored. The IAPT-adopted KPI for patients “moving to recovery” as a proportion of those completing treatment, as published by the DH, is forty-four per cent. Using those starting therapy as a denominator, the rate falls to twenty-two per cent. Using as the denominator all patients “referred” to the IAPT programme, this figure is still lower, at twelve per cent. Commissioners of psychological therapies in primary care will want to exercise their own judgement as to which of these figures offers transparency to support analysis of outcomes. Recognition and understanding of the needs and experience of the high proportion of patients who have one or fewer contacts with therapists should be a high priority in the development of commissioning for psychological therapy.
Moments Of Products Of L-Functions

We first consider questions on the distribution of the primes. Using the recent advancement towards the Prime k-tuple Conjecture by Maynard and Tao, we show how to produce infinitely many strings of consecutive primes satisfying specified congruence conditions. We answer an old question of Erdős and Turán by producing strings of consecutive primes whose successive gaps form an increasing (respectively decreasing) sequence. We also show that such strings exist whose successive gaps follow a certain divisibility pattern. Finally, for any coprime integers a and D ≥ 1, we refine a theorem of D. Shiu and find strings of consecutive primes of arbitrary length in the congruence class a mod D. These results were proved jointly with William D. Banks and Tristan Freiberg. We next consider the vertical distribution of the nontrivial zeros of certain Dedekind zeta-functions. In particular, let K be a quadratic number field, and let ζK(s) denote the Dedekind zeta-function attached to K. Using the mixed second moments of derivatives of ζK(s) on the critical line, we prove the existence of gaps between consecutive zeros of ζK(s) on the critical line which are at least √ 6 = 2.44949 . times the average spacing. Finally, assuming the Generalized Riemann Hypothesis and some standard conjectures, we prove upper bounds for moments of arbitrary products of automorphic L-functions and for Dedekind zeta-functions of Galois number fields on the critical line. As an application, we use these bounds to estimate the variance of the coefficients of these zetaand L-functions in short intervals. We also prove upper bounds for moments of products of central values of automorphic L-functions twisted by quadratic Dirichlet characters and averaged over fundamental discriminants. These results were proved jointly with Micah B. Milinovich.
Stability results for a class of neutral functional differential equations. A Liapunov like analysis.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Stability results for a class of neutral functional differential equations. A Liapunov like analysis. Silviu-Iulian Niculescu, Vladimir Rasvan
Diet and physical activity behaviour in nurses: a qualitative study

Issue addressed: Previous research has shown that approximately 60% of nurses in Australia are overweight or obese, insufficiently active and have an unhealthy diet. The aim of this study was to gain an understanding of nurses’ determinants contributing to these behaviours. This will inform a needs assessment for a future workplace health promotion program (WHPP) in this group. Methods: Four focus group discussions (n = 17) were conducted with a convenience sample of nurses aged 25–59 years from three hospitals in the Brisbane metropolitan area. Questions addressed barriers and motivation towards diet and physical activity (PA), and suggestions for future WHPP. Data were analysed with Nvivo10 following a thematic analysis with a realistic approach using Self-determination theory as a framework. Results: Work environment was the main barrier for healthy diet behaviours. Long working hours and lack of breaks challenged nurses’ self-control and self-regulation when making dietary choices. Fatigue was the main barrier for PA. However, relaxation, feeling energised before work and better sleep after working night shifts motivated nurses to do PA. Social environment at work seemed to be an effective external motivation to encourage healthy diet and regular PA. Goal-setting, self-monitoring and social support at work were identified as potential WHHP strategies. Conclusion: The workplace and job demands negatively impacts nurses’ lifestyle behaviours. Future interventions should include social support from colleagues, which could motivate nurses to make healthier food choices at work and be more active outside work.
The impact of the domain boundary on an inhibitory system: Interior discs and boundary half discs

When the Ohta-Kawasaki theory for diblock copolymers is applied to a bounded domain with the Neumann boundary condition, one faces the possibility of micro-domain interfaces intersecting the system boundary. In a particular parameter range, there exist stationary assemblies, stable in some sense, that consist of both perturbed discs in the interior of the system and perturbed half discs attached to the boundary of the system. The circular arcs of the half discs meet the system boundary perpendicularly. The number of the interior discs and the number of the boundary half discs are arbitrarily prescribed and their radii are asymptotically the same. The locations of these discs and half discs are determined by the minimization of a function related to the Green's function of the Laplace operator with the Neumann boundary condition. Numerical calculations based on the theoretical findings show that boundary half discs help lower the energy of stationary assemblies.
Accuracy Analysis of Aerodynamic Calculation of Twodimensional Ballistic correction Projectile based on Missile Datcom

Missile Datcom (hereinafter referred to as Datcom) is an aerodynamic engineering calculation software developed by the US Air Force Research Laboratory. It is commonly used in the preliminary design of the shape scheme of missiles, aircraft and other aircraft. In this paper, Datcom is used to calculate the aerodynamic parameters of a two-dimensional ballistic correction projectile(D2BCP), and the calculated data is compared with the wind tunnel test data. The analysis results show that Datcom calculates the axial force coefficient (CA) of the projectile with large system deviation, however, the deviation can be eliminated by a certain compensation, thereby obtaining a more accurate CA of the projectile. Datcom calculates the normal force coefficient (CN) with high Mach number accuracy, but there is an unacceptable deviation of the projectile CN calculated at small angle of attack ( α ). The calculation of pitching moment coefficient with α (CMa) is higher, but the error is larger under individual Mach numbers.
Design of reduced-order interval observers for LTI systems with bounded time-varying disturbances: a parametric approach

This paper investigates the design problem of reduced-order interval observers for linear time-invariant systems with bounded time-varying disturbances. Although there are many excellent design methods of interval observers, it is still a worth discussing problem to construct the cooperativity of observer error dynamics. Firstly, under the full consideration of anti-interference point, a general approach to design a reduced-order interval observer is proposed, and the complexity of constructing the system cooperativity is decreased. Secondly, a parametric design method of the reduced-order interval observers is further built on the above one by solving a type of generalised Sylvester equations, which ensures the existence of the reduced-order interval observers, and the calculation problem of linear matrix inequalities is avoided effectively. Besides, one further novelty is the consideration of the parameters whose influence on the observer performance, such as the convergence rate of the output interval and robustness. Meanwhile, a constructive procedure to obtain a reduced-order interval observer is advanced. Finally, the effectiveness of the proposed method is illustrated through numerical simulations.
Automatic optical-to-SAR image registration using a structural descriptor

Optical-to-synthetic aperture radar (SAR) image registration is a challenging task in remote sensing as the images have significant non-linear intensity variations as well as large geometric differences. Moreover, the influence of speckle noise in the SAR image further affects the registration result. The structural descriptors are very effective to handle the non-linear intensity variations between optical and SAR images. Although a number of optical-to-SAR image registration methods have been proposed in the past few years based on the structural information of image, most of them are ineffective for the images having large geometric differences. To address these problems, a novel optical-to-SAR image registration algorithm is proposed by using a new structural descriptor. Initially, the corner features are extracted from the optical and SAR images. Then, the proposed structural descriptor is constructed for the extracted features. Finally, feature matching is performed between the optical and SAR images and the correct match are identified. The proposed method is very effective to register the optical and SAR images having significant intensity variations and large geometric differences. It can increase the number of correct match between the images. Experiments on six sets of optical and SAR image pairs demonstrate the effectiveness of the proposed method.
Spectral Hypergraph Partitioning and Relative Entropy

This thesis is about the information-theoretic difference between hypergraphs and undirected graphs, which arises in spectral bisections of these objects. We also investigate the effect of general deletion and contraction operations of hyperedges in a hypergraph from different points of view. We restrict ourselves to a wellstructured class of hypergraphs, namely, simplicial complexes. This allows us to define higher-dimensional Laplace operators, which generalize graph Laplacians in a natural way. Similarly, isoperimetric numbers for graphs combinatorial Cheeger constants can be extended to simplicial complexes. We suggest a new isoperimetric quantity for simplicial complexes, based on minimal interaction loss, and show an isoperimetric inequality for them. The Kullback-Leibler divergence, also known as relative entropy, is used to consider the difference between simplicial complexes and undirected graphs from an information-theoretic point of view. By means of hierarchical exponential families, which are naturally induced by simplicial complexes, we define a relative entropy between simplicial complexes. For a systematic investigation of this relative entropy we consider its effect under certain operations, like deletion and contraction of simplices in a simplicial complex. With a detailed analysis of marginalized exponential families and with already known decomposition formulas for the Kullback-Leibler divergence, we succeed to identify a class of operations on simplicial complexes for which we can deduce many exact expressions and inequalities for the relative entropy. For more general operations on simplicial complexes we can show an upper bound for the relative entropy. Through an explicit construction of probability distributions we are able to state lower bounds of the relative entropy between separated and non separated simplicial complexes. Based on the observation from spectral graph theory, in which the smallest nontrivial eigenvalue of the Laplacian is related to a combinatorial Cheeger constant, we show a connection of this eigenvalue to scaled relative entropies. For this purpose, an information-theoretic Cheeger constant is introduced, which is related to a combinatorial Cheeger constant. This allows us to derive information-theoretic Cheeger inequalities for undirected graphs and simplicial complexes. In particular, it is possible to see the information-theoretic difference between undirected graphs and simplicial complexes by means of an entropy gap.
Monte Carlo Analysis of Time-Varying Parameter Models with Stochastic Volatility

This paper considers time-varying autoregressive models with stochastic volatility. In contrast to the widely used Bayesian approaches, we develop a classical maximum likelihood estimator. The estimation procedure is based on a multivariate extension of the numerically accelerated importance sampling together with a RaoBlackwellization step to construct a highly efficient estimation procedure. In addition, a novel specification for non-linear time-varying parameter models is developed summarizing the time-variation in the coefficients through a common factor structure, greatly enhancing estimation and retaining model flexibility. An extensive Monte Carlo study shows that the importance sampling procedure can identify model parameters and its likelihood estimator compares favorably to the particle filter. We applied the proposed specifications to U.S. C.P.I. inflation and we show it is able to accommodate the observed dynamics in inflation. Estimates of the time-varying parameters indicate the importance of the random innovations in explaining the inflation process, while the trend component is more stable than previously found in the literature. An out-of-sample forecasting exercise showed superior results with respect to benchmark models, both in point and density forecasting. In addition,
Three‐Dimensional Mapping of Lightning‐Produced Ionospheric Reflections

The powerful high‐frequency/very high frequency radio emissions that occur during lightning flashes can be used as a signal of opportunity to study the bottom side ionosphere. The lightning emission is bright, broad spectrum, and short in duration, providing an ideal signal of opportunity for making ionograms. This study continues previous work in Obenberger et al. (2018), where the direct line of sight signal from lightning can be cross correlated with megahertz frequency radio telescope observations to reveal ionogram traces created from the reflected lightning signals. This process was further developed to automate production of ionograms made from individual lightning flashes over the course of several hours, as well as create new techniques to detect the lightning signal using the all‐sky‐imaging mode. By using the Long Wavelength Array Sevilleta radio telescope as an interferometer, the point of reflection of the lightning signal for each frequency of the ionogram can be located in the ionosphere, instantaneously revealing density gradients within the ionosphere on minute time scales. We also explore the minimum size stations required for the application of this technique, which we found to be at least 32 antennas.
A study on analysis of blood donation deferral during blood donation camp at tertiary-care teaching hospital in south Gujarat region

Background: Blood is lifesaving medicine for critically ill patients. Blood donations save many lives in the world. With that blood is very important for vitality of humans. So, in the blood donations, it is very important to maintain safety of donor and recipient. For that, donor selection is the most important criterion of blood donation. Objective: To find out the reasons for deferrals of blood donors at volunteer blood donation camp. Materials and Methods: This cross-sectional study was carried out at blood bank in GMERS Medical College, Valsad, Gujarat, India. In this study, investigator visited volunteer blood donation camps organized by blood bank during 1 month. Each donor was examined by the medical officer based on detailed medical history and brief physical examination as per the criteria laid down by Director General Health services and drugs controller of India. Data were presented as percentages, and analysis of data was done by using MS Excel. Result: During the study period, a total of 161 volunteers were willing to donate blood. Of them, 132 (81.99%) were male and 29 (18.01%) female volunteers. Most of the volunteer blood donors belonged to 21–30 years of age group (37.89%). Among them, 161 volunteers for blood donation, 28 (17.39%) of them were rejected because of various reasons, and three (1.86%) persons did not donate blood. The most common reason for deferral in this study was history of jaundice (35.71%). Other causes were anemia, high blood pressure, and menorrhagia. Conclusion: In this study, reasons for rejection of volunteer blood donors were studied. The most common reason of such rejection was history of jaundice. Other reasons were anemia, hypertension, heart disease, etc.
Self-similar compressible turbulent boundary layers with pressure gradients. Part 2. Self-similarity analysis of the outer layer

A thorough self-similarity analysis is presented to investigate the properties of self-similarity for the outer layer of compressible turbulent boundary layers. The results are validated using the compressible and quasi-incompressible direct numerical simulation (DNS) data shown and discussed in the first part of this study; see Wenzel et al. (J. Fluid Mech., vol. 880, 2019, pp. 239–283). The analysis is carried out for a general set of characteristic scales, and conditions are derived which have to be fulfilled by these sets in case of self-similarity. To evaluate the main findings derived, four sets of characteristic scales are proposed and tested. These represent compressible extensions of the incompressible edge scaling, friction scaling, Zagarola–Smits scaling and a newly defined Rotta–Clauser scaling. Their scaling success is assessed by checking the collapse of flow-field profiles extracted at various streamwise positions, being normalized by the respective scales. For a good set of scales, most conditions derived in the analysis are fulfilled. As suggested by the data investigated, approximate self-similarity can be achieved for the mean-flow distributions of the velocity, mass flux and total enthalpy and the turbulent terms. Self-similarity thus can be stated to be achievable to a very high degree in the compressible regime. Revealed by the analysis and confirmed by the DNS data, this state is predicted by the compressible pressure-gradient boundary-layer growth parameter $\unicode[STIX]{x1D6EC}_{c}$ , which is similar to the incompressible one found by related incompressible studies. Using appropriate adaption, $\unicode[STIX]{x1D6EC}_{c}$ values become comparable for compressible and incompressible pressure-gradient cases with similar wall-normal shear-stress distributions. The Rotta–Clauser parameter in its traditional form $\unicode[STIX]{x1D6FD}_{K}=(\unicode[STIX]{x1D6FF}_{K}^{\ast }/\bar{\unicode[STIX]{x1D70F}}_{w})(\text{d}p_{e}/\text{d}x)$ with the kinematic (incompressible) displacement thickness $\unicode[STIX]{x1D6FF}_{K}^{\ast }$ is shown to be a valid parameter of the form $\unicode[STIX]{x1D6EC}_{c}$ and hence still is a good indicator for equilibrium flow in the compressible regime at the finite Reynolds numbers considered. Furthermore, the analysis reveals that the often neglected derivative of the length scale, $\text{d}L_{0}/\text{d}x$ , can be incorporated, which was found to have an important influence on the scaling success of common ‘low-Reynolds-number’ DNS data; this holds for both incompressible and compressible flow. Especially for the scaling of the $\bar{\unicode[STIX]{x1D70C}}\widetilde{u^{\prime \prime }v^{\prime \prime }}$ stress and thus also the wall shear stress $\bar{\unicode[STIX]{x1D70F}}_{w}$ , the inclusion of $\text{d}L_{0}/\text{d}x$ leads to palpable improvements.
A QUALITATIVE PERSPECTIVE OF ACADEMIC READING PRACTICES AND OVERCOMING STRATEGIES USED AMONG INTERNATIONAL GRADUATE STUDENTS IN MALAYSIA

This article presents the qualitative findings of a research that investigates the challenges faced by international graduate students with academic reading and the overcoming strategies applied by them in their reading. This qualitative study utilized focus group interviews with 70 international graduate students in post graduate programs at tertiary level in Malaysia. The findings highlight some important findings for students, academicians and university administrators. The findings indicate that international graduate students do face challenges and problems which are ascribed to the fact that English is the medium of instruction. In addition, the findings also exposes the strategies employed by the students to overcome the reading obstacles faced in their academic reading practices. This article concludes with suggestions for administrative policies and reading related programs to assist the academic reading needs of the students.