Miracle-dz/UniFAR-FTUs huggingface dataset:
Examining the Impact of Perinatal Deaths on the Mothers in the Tamale Metropolis, Northern Ghana

Perinatal loss has serious implications on the lives of the affected women and sometimes on the family. However, not much is known in the empirical literature, especially in the Tamale Metropolitan area. This paper sets out to examine the impact of neonatal deaths on women. The study was conducted in three major hospitals in Tamale and involved 384 women and 10 medical officers. The study employed mainly interviews, questionnaires and a review of secondary data including hospital records. The study found that, apart from the emotional trauma, affected women sometimes suffer stigma and are subjected to traditional rituals in order to ‘cleans’ them. The women also entertained the fear of getting a miscarriage or suffering from perinatal death in the future, the study recommends counseling and sensitization for pregnant women to avoid future perinatal deaths.
Portfolios under Different Methods and Scenarios: A Case of Fiji’s South Pacific Stock Exchange

In this study, we analyze portfolio performance under different methods and scenarios for the small island economy of Fiji. In addition to documenting the historical performance and the smallness of the stock market, the study looks at the possibility of opting for an equally weighted (naïve) portfolio against market and minimum variance portfolios. To this end, we extract monthly stock price data of 17/19 listed companies from August 2019 to July 2022 and invoke different approaches to develop portfolios under different scenarios. We consider the mean-variance, minimum variance, semi-variance, utility maximization, and minimum turbulence portfolios, based on beta-adjusted (CAPM-based) returns. The different portfolios presented in the study should provide some insights on asset allocation in Fiji’s stock market. Interestingly, unlike average returns, the beta-adjusted returns indicate that an equally weighted portfolio can yield relatively higher expected returns than market portfolios, although, with a relatively higher standard deviation and lower Sharpe ratio than the optimized results. In a semi-variance analysis (where we account for downside risk only), equally weighted portfolio yields superior returns, albeit with a relatively lower Sortino ratio. Given that Fiji’s stock market is currently a small, with a relatively small number of listed companies, potential and less sophisticated investors and analysts considering portfolios based on beta-adjusted returns, may simply opt for 1/N (naïve) portfolios as a diversification strategy while realizing decent expected returns. The optimized portfolio under mean-variance, semi-variance, and utility are presented as alternative considerations for nuanced investors. Additionally, equally weighted turbulence-adjusted and minimum-turbulence portfolios are constructed to capture periods of unusualness and calmness in the market. The methodologies and the results presented can be adjusted and applied to other small markets and hence can influence investment decisions of investors in creating diversified portfolios under different scenarios.
On the Stability of Frames and Riesz Bases

Abstract The first part of this paper supplements the recent work of Heil and Christensen on the stability of frames in Banach and Hilbert spaces. After obtaining a multivariate version of Kadec′s 1/4-theorem (which is used in the sequel), two of Christensen′s results, Chui and Shi′s Second Oversampling Theorem, and a variety of other results and techniques are applied to study the stability of multivariate exponential, wavelet, and Gabor frame and Riesz bases. Specific frame bounds and quantitative conditions of validity for mother wavelet and sampling perturbations are given.
Perceived discrimination and alcohol consumption in an indigenous population

Introduction. Indigenous populations are considered a vulnerable minority and have characteristics such as poverty, difficulties to access food, housing, and educational backwardness; these conditions make them prone to alcohol consumption problems. Dependence on alcohol consumption probably arises as a symbol of protest, challenge, and response to social anguish, which has in turn repercussions in marginal population sectors that have conditions of fragility due to exploitation and discrimination, such as indigenous people. Objective. To know the effect of perceived discrimination on alcohol consumption in Mexican indigenous population. Method. Research design was descriptive, correlational check-model, with a sample of 362 adults from two indigenous communities. Results. A simple linear regression model was performed, which shows a significant effect in the entire model (F[248] = 78.312, p = .001), which explains 49% of the variance of alcohol consumption. A significant positive influence was also found from the perceived discrimination variable (β = .626, p #abr# .001) on alcohol consumption. Discussion and conclusion. The studied indigenous communities had characteristics that the literature highlights as risk factors for developing addictive behaviors of alcohol consumption. These results coincide with those of the National Commission for the Development of Indigenous Peoples. Indigenous population present discrimination problems that are associated with alcohol consumption problems.
Kinematic optimization of 2D plunging airfoil motion using the response surface methodology

The propulsive efficiency of a plunging NACA0012 airfoil is maximized by means of a simple numerical optimization method based on the response surface methodology (RSM). The control parameters are the amplitude and the reduced frequency of the harmonic sinusoidal motion. The 2D unsteady laminar flow around the plunging airfoil is computed by solving the Navier-Stokes equations for three Reynolds number values (Re = 3.3×103, 1.1×104, and 2.2×104). The Nelder-Mead algorithm is used to find the best control parameters leading to the optimal propulsive efficiency over the constructed response surfaces. It is found that, for a given efficiency level and regardless of the considered Re value, it is possible either to obtain high thrust by selecting a high oscillation frequency or to reduce the input power by adopting a low plunging amplitude.
A Descriptive Analysis of Corporate Governance Mechanisms and Earnings Management in Palestine

Research aims: The article aims to describe corporate governance (CG) characteristics and the extent of earnings management (EM) practices in non-financial firms listed on the Palestine Exchange from 2011 to 2018.Design/Methodology/Approach: The study employed the quantitative methodology. Collected data were summarized quantitatively using descriptive analysis with STATA 14. CG data were retrieved manually from published annual financial reports, while financial data for the EM calculation were collected from Thomson ONE.Research findings: Listed non-financial firms in Palestine only moderately complied with the Palestinian Code of Corporate Governance. Some Palestinian firms have also established an audit committee, one of the most important corporate governance mechanisms.Theoretical contribution/Originality: The findings provide insight into CG and EM in Palestine for regulators and policymakers. Practitioner/Policy implication: The results can assist policymakers in strengthening existing regulations and updating the current code of CG or introducing new policies to mitigate EM.
Millimeter-wave investigation of the antiferromagnetic phase in λ − ( BETS ) 2 FeCl 4 in high magnetic fields

The antiferromagnetic metal-insulator transition in the magnetic-organic conductor λ-(BETS) 2 FeCl 4 has been probed by resonant cavity mm wave methods vs magnetic field, temperature, frequency, and sample orientation. Although the general form of the ac response follows expectations for passage from a skin depth regime to a depolarization regime as the metal-insulator phase boundary is crossed, additional features appear below the metal-insulator transition. This behavior indicates that metastable changes in the ground state occur within the insulating phase.
Generalized Hadamard matrices whose transposes are not generalized Hadamard matrices

In answer to “Research Problem 16” in Horadam's recent book Hadamard matrices and their applications, we provide a construction for generalized Hadamard matrices whose transposes are not generalized Hadamard matrices. © 2009 Wiley Periodicals, Inc. J Combin Designs 17: 456–458, 2009
The analysis of robust D-stability for uncertain linear systems

The D-stability robustness in a specified sector of uncertain linear systems is transformed into a nonsingularity problem of a family of parameterized matrices and then the D-stability bounds keeping the poles of the systems in the sector in left-half plane are derived and the stability bounds are also given. These bounds do not imply quadratic stability or quadratic D-stability and are approximated to their practical values and they are the actual robust stability and D stability bounds indeed when there is only one perturbed parameter.
The Poisson INAR(1) CUSUM chart under overdispersion and estimation error

The Poisson INAR(1) CUSUM chart has been proposed to monitor integer-valued autoregressive processes of order 1 with Poisson marginals. The effectiveness of this chart has been shown under the assumptions of Poisson marginals and known in-control process parameters, but these assumptions may not be very well satisfied in practical applications. This article investigates the practical issues concerning applications of the Poisson INAR(1) CUSUM chart, considering average run lengths obtained through a bivariate Markov chain approach. First, the effects of deviations from the assumed Poisson model are investigated when there is overdispersion. Design recommendations for achieving robustness are provided along with an extension, the Winsorized Poisson INAR(1) CUSUM chart. Next, analyzing the conditional average run length performance under some hypothetical cases of parameter estimation, it is shown that estimation errors may severely affect the chart’s performance. The marginal average run length performance is used to derive sample size recommendations. An example for monitoring the number of beds occupied at a hospital emergency department is used to illustrate the proposed approach.
Global maps of microwave land surface emissivities: Potential for land surface characterization

Microwave land surface emissivities are derived from special sensor microwave imager (SSM/I) observations. Cloud‐free SSM/I observations are first isolated with the help of collocated visible/infrared satellite observations (International Satellite Cloud Climatology Project (ISCCP) data). Then, the cloud‐free atmospheric contribution is calculated from an estimate of the local atmospheric temperature‐humidity profile (National Centers for Environmental Prediction (NCEP) analyses). Finally, with the surface skin temperature derived from IR observations (ISCCP estimate), the surface emissivity is calculated for all the SSM/I channels. The method is applied to the SSM/I data for the globe for October 1991. Correspondences between geographical patterns of the emissivities and surface characteristics are briefly analyzed to investigate the potential of microwave emissivities to monitor vegetation phenology and surface properties at regional and continental scales.
The effects of COVID-19 on the water sector

The COVID-19 pandemic affected public health, economy, social life, and the environment. It infected and killed millions of people around the world. Most of the recent literature has focused on the medications to combat this virus, including antivirals and vaccines, but studies about its effect on the environment are still rare, particularly on the water sector. Most of the studies concentrate on the effect of water availability on COVID-19, the effect of the used medications on the water, and the probability of transmission of SARS-CoV-2 through water. Herein, we have summarized the effects of COVID-19 on the water sector from many perspectives. We show different methods to detect the effect of the pandemic on water and also methods to investigate the presence of the virus or its RNA in the water. We also show the different effects of its presence in the wastewater, the probability of transmission, the detection of different variants, and the prediction of new waves. We also show the disadvantages and advantages of the pandemic in the water sector. We finally suggest some recommendations to face this pandemic and the future pandemics for the governments and water policymakers, water treatment plants, general population, and researchers. The aim of this review is to show the different aspects of the pandemic in order to give a general idea about what must be done in order to minimize its effect and any probable pandemic in the future.
Birefringence of cellotape: Jones representation and experimental analysis

In this paper, we analyse a simple experiment to study the effects of polarized light. A simple optical system composed of a polarizer, a retarder (cellotape) and an analyser is used to study the effect on the polarization state of the light which impinges on the setup. The optical system is characterized by means of a Jones matrix, and a simple procedure based on Jones vectors is used to obtain an expression for the intensity after the light passes through the optical system. The light intensity is measured by a photodetector and the expression obtained theoretically is experimentally validated. By fitting the experimental intensity data, the value of the retardation introduced by the retarder can also be obtained.
Interpretation and further development of the hypnodensity representation of sleep structure

Objective. The recently-introduced hypnodensity graph provides a probability distribution over sleep stages per data window (i.e. an epoch). This work explored whether this representation reveals continuities that can only be attributed to intra- and inter-rater disagreement of expert scorings, or also to co-occurrence of sleep stage-dependent features within one epoch. Approach. We proposed a simplified model for time series like the ones measured during sleep, and a second model to describe the annotation process by an expert. Generating data according to these models, enabled controlled experiments to investigate the interpretation of the hypnodensity graph. Moreover, the influence of both the supervised training strategy, and the used softmax non-linearity were investigated. Polysomnography recordings of 96 healthy sleepers (of which 11 were used as independent test set), were subsequently used to transfer conclusions to real data. Main results. A hypnodensity graph, predicted by a supervised neural classifier, represents the probability with which the sleep expert(s) assigned a label to an epoch. It thus reflects annotator behavior, and is thereby only indirectly linked to the ratio of sleep stage-dependent features in the epoch. Unsupervised training was shown to result in hypnodensity graph that were slightly less dependent on this annotation process, resulting in, on average, higher-entropy distributions over sleep stages (H unsupervised = 0.41 versus H supervised = 0.29). Moreover, pre-softmax predictions were, for both training strategies, found to better reflect the ratio of sleep stage-dependent characteristics in an epoch, as compared to the post-softmax counterparts (i.e. the hypnodensity graph). In real data, this was observed from the linear relation between pre-softmax N3 predictions and the amount of delta power. Significance. This study provides insights in, and proposes new, representations of sleep that may enhance our comprehension about sleep and sleep disorders.
Nonlinear effects during the motion of vortices in superconductors

The order parameter depends strongly on the coordinates in the mixed state in superconductors. A kinetic equation is derived in this case which describes the excitation-energy distribution function. This function varies strongly in a comparatively weak electric field E. At low temperatures, the effective electron temperature is proportional to E/sup 2/5/. If this temperature exceeds the energy gap, most of the energy of the stationary electric field should transform into energy of almost-monochromatic phonons. The boundary condition for the diffusion equation is obtained in the case of high impurity concentrations.
Output-sliding control design of multivariable systems

A theoretical development of output-sliding control for uncertain mismatched multivariable systems is presented. The control law consists of a continuous nominal control part and a discontinuous switching control part. The determination of controller gains is explicit and practical. The closed-loop eigenvalues assignment in the sliding mode is well addressed. System robustness against a larger class of parameter variations and disturbances than by conventional design methods is achieved. Simultation studies show the promise of the proposed method.
Molecular Dynamics Study on Structure, Vibrational Properties, and Transport Coefficients of Liquid Alumina

The structure, vibrational density of states, and transport coefficients of liquid alumina were studied using molecular dynamics simulations. At the temperature of 2500 K, 3000 K, 3500 K, and 4000 K, systems with three different densities were constructed, respectively, including the configurations with densities of 2.81 g/cm3 and 3.17 g/cm3, and the relaxed ones with nearly zero pressure at each temperature. With the changes in temperature or density, the transformations on the structural, vibrational and transport properties were discussed. The Born–Mayer–Huggins type of atomic interactions was used, with newly optimized parameters. The analysis of the interatomic correlations indicated that the short-range order of liquid alumina was mainly constructed by AlO4 tetrahedra, also a certain number of AlO3 and AlO5 was present. Meanwhile, the structural transitions on the elemental units occurred as either the temperature or density increased. Two primary frequency bands were observed in each vibrational density of states spectrum, with the higher frequency bands produced by the O atom vibrations, and the lower frequency ones generated by the Al atom vibrations. Self-diffusion coefficients were estimated using the linear behavior of the mean-squared displacement at long time, while by using the Green–Kubo relation during equilibrium molecular dynamics simulations, thermal conductivities and viscosities were calculated. Significantly, the viscosity at 2500 K with a density of 2.81 g/cm3 was equal to 25.23 mPa s, which was very close to the experimental finding.
Approximation of American Put Prices by European Prices via an Embedding Method

In mathematical finance, the price of the so-called "American Put option" is given by the value function of the optimal-stopping problem with the option payoff *: x -(K x)+ as a reward function. Even in the Black-Scholes model, no closed-formula is known and numerous numerical approximation methods have been specifically designed for this problem. In this paper, as an application of the theoretical result of B. Jourdain and C. Martini [Ann. Inst. Henri Poincare Anal. Nonlinear 18 (2001) 1-17], we explore a new approximation scheme: we look for payoffs as close as possible to uf, the American price of which is given by the European price of another claim. We exhibit a family of payoffs indexed by a measure h, which are continuous, match with (K x)+ outside of the range ]K*, K[ (where K* is the perpetual Put strike), are analytic inside with the right derivative (-1) at both ends. Moreover a numerical procedure to select the best h in some sense yields nice results.
H∞ Observer Design for Descriptor Systems with Slope‐Restricted Nonlinearities

This paper considers the H∞ observer design problem for a class of nonlinear descriptor systems subject to disturbances. A linear matrix inequality (LMI)‐based observer design method is derived such that the error system is internally exponentially stable with a given decay rate and the L 2 gain of the mapping from the disturbances to the error output is less than or equal to a prescribed level. It is further shown that the solution to the obtained observer system exists and is unique for any compatible initial condition. Two convex optimization problems are formulated to improve the estimation performance. The obtained results are illustrated by numerical examples.
Exploring Coping Strategies and Social Support among Individuals with Compulsive Sexual Behavior Concerns: Results from a Clinical Sample

Abstract Compulsive sexual behavior (CSB) is associated with poor affect regulation and difficulties in interpersonal relationships. People experiencing CSB may engage in ineffective coping and have poor social support. The current study tested relationships between several coping orientations and sources of perceived social support (from significant others, friends, and family) among men seeking treatment for CSB and other sexual health and relationship concerns. Results indicated that religion and self-blame coping orientations predicted greater CSB concerns. Social support from friends and coping with humor were associated with lower CSB. These findings identify potential areas of intervention to target CSB-related concerns.
Self-similarity of near-breaking short gravity wind waves

We show that the asymmetric profiles of the near-breaking wind waves observed in a large wind-wave tank do not depend on the wave scale. The experiments were performed for wind-generated waves of wavelength increasing with fetch. The wave crests just prior to breaking exhibit steep slopes exceeding 0.6 at the front and much smaller but remarkably constant slope at the rear. The statistics of wave geometric properties, such as the along-wind crest-slope distribution or the wavefront steepness, is found to be scale invariant. This implies that the shape of the near-breaking wind waves is self-similar. Similar experiments with paddle-generated waves amplified by wind reveal the same scale-independent features. These results suggest a certain universality of the underlying physical mechanisms leading to breaking for wave fields in equilibrium with wind.
A new exponential model for predicting soil gas diffusivity with varying degree of saturation

Soil gas diffusivity (Dp/Do, gas diffusion coefficients in soil and in free air, respectively) and its relation to soil moisture is of great importance for describing and quantifying essential provisional and regulatory functions associated with terrestrial ecosystems such as soil aeration and greenhouse gas (GHG) emissions. Because gas migration in terrestrial soil systems is predominantly diffusion controlled, soil gas diffusivity becomes a fundamental prerequisite to quantify diffusive gas fluxes. Descriptive–predictive models are often used to estimate Dp/Do from easily measurable soil physical properties. Most of the available models take the form of power‐law functions and often tend to mischaracterize soil moisture effects at high moisture regimes. Based on a wide range Dp/Do data available in literature representing both intact and repacked soils, this study developed a novel air‐saturation‐dependent exponential (ASEX) gas diffusivity model to model Dp/Do in relation to soil air saturation. The model variable α, which represents the diffusivity at half air saturation normalized by the same in complete soil air saturation, could potentially differentiate moisture effects on different soil structural states. For specific applications in intact soils, we propose corresponding α values for upper‐limit (α = .6) and lower‐limit (α = .05) estimates of diffusivity, while an average value (α = .3) for general applications in both intact and repacked soils. As expected, our model based on a few a priori measured supportive data showed a better performance over the classical predictive models that do not use such measurements. The new model was further used to derive useful implications to showcase soil density effects on Dp/Do.