Miracle-dz/UniFAR-FTUs huggingface dataset:
Transmission gaps and Fano resonances in an acoustic waveguide: analytical model

A simple acoustic device consisting of two dangling side resonators grafted at two sites on a slender tube is designed possibly to obtain transmission stop bands (where the propagation of longitudinal acoustic waves is forbidden). In contrast to all known systems of this kind, a spectral transmission gap of nonzero width occurs here even with this simple structure. This is obtained by combining appropriately the zeros of transmission of the side resonators. Sharp resonant states inside the gaps can be achieved without introducing any defects in the structure. This results from an internal resonance of the structure when such a resonance is situated in the vicinity of a zero of transmission or placed between two zeros of transmission, the so-called Fano resonances. A general analytical expression for the transmission coefficient is given for various systems of this kind within the framework of the Green’s function method. The amplitude and the phase of the transmission are discussed as a function of frequency and it is shown that the width of the stop bands is very sensitive to the number of side resonators. These results should have important consequences for the suppression of low-frequency noise and for designing filters.
Renal Papillary Necrosis (RPN) in an African Population: Disease Patterns, Relevant Pathways, and Management

Renal papillary necrosis (RPN) is characterized by coagulative necrosis of the renal medullary pyramids and papillae. Multiple conditions and toxins are associated with RPN. Several RPN risk factors, or POSTCARDS, have been identified, with most patients presenting with RPN having at least two contributing risk factors. Currently, there is no specific test to diagnose and confirm RPN; however, several imaging tools can be used to diagnose the condition. RPN is currently underdiagnosed in African populations, often with fatal outcomes. In African clinical settings, there is a lack of consensus on how to define and describe RPN in terms of kidney anatomy, pathology, endourology, epidemiology, the identification of African-specific risk factors, the contribution of oxidative stress, and lastly an algorithm for managing the condition. Several risk factors are unique to African populations including population-specific genetic factors, iatrogenic factors, viral infections, antimicrobial therapy, schistosomiasis, substance abuse, and hypertension (GIVASSH). Oxidative stress is central to both GIVASSH and POSTCARDS-associated risk factors. In this review, we present information specific to African populations that can be used to establish an updated consensual definition and practical grading system for radiologists, urologists, nephrologists, nuclear physicians, and pathologists in African clinical settings.
WINGLET-TYPE VORTEX GENERATORS WITH COMMON-FLOW-UP CONFIGURATION FOR FIN-TUBE HEAT EXCHANGERS

This investigation stems from the area of augmentation of heat transfer by generating streamwise longitudinal vortices. The vortex generators are arranged in a common-flow-up configuration. Existing air-cooled condensers in geothermal power plants use fin-tube heat exchangers with circular tubes. The heat exchangers are huge, and often the cost of the condensers is more than one-third of the plant cost. The size of the condensers can be reduced through enhancement of heat transfer from fin surfaces. The enhancement strategy involves introduction of strong swirling motion in the flow field. The swirl can be generated by the longitudinal vortices. In this study, the longitudinal vortices are created by delta winglet-type vortex generators, which are mounted behind the tubes. An element of a heat exchanger has been considered for detailed study of the flow structure and heat transfer analysis. Biswas and colleagues have obtained significant enhancement of heat transfer by deploying the winglet pair behind each tube. In this study, a novel technique (Torii and colleagues [2]) has been utilized for the enhancement. The winglets are placed with a heretofore unused orientation for the purpose of augmentation of heat transfer. This orientation is called the common-flow-up configuration. The proposed method causes significant separation delay, reduces form drag, and removes the zone of poor heat transfer from the near wake of the tubes. The analyses of flow and heat transfer in the proposed configuration have been accomplished through a numerical solution of complete Navier-Stokes and energy equations.
On the construction of recurrence relations for the expansion and connection coefficients in series of Jacobi polynomials

Formulae expressing explicitly the Jacobi coefficients of a general-order derivative (integral) of an infinitely differentiable function in terms of its original expansion coefficients, and formulae for the derivatives (integrals) of Jacobi polynomials in terms of Jacobi polynomials themselves are stated. A formula for the Jacobi coefficients of the moments of one single Jacobi polynomial of certain degree is proved. Another formula for the Jacobi coefficients of the moments of a general-order derivative of an infinitely differentiable function in terms of its original expanded coefficients is also given. A simple approach in order to construct and solve recursively for the connection coefficients between Jacobi–Jacobi polynomials is described. Explicit formulae for these coefficients between ultraspherical and Jacobi polynomials are deduced, of which the Chebyshev polynomials of the first and second kinds and Legendre polynomials are important special cases. Two analytical formulae for the connection coefficients between Laguerre–Jacobi and Hermite–Jacobi are developed.
The Consistency and Robustness of Modified Cramér–Von Mises and Kolmogorov–Cramér Estimators

This article focuses on the minimum distance estimators under two newly introduced modifications of Cramér–von Mises distance. The generalized power form of Cramér–von Mises distance is defined together with the so-called Kolmogorov–Cramér distance which includes both standard Kolmogorov and Cramér–von Mises distances as limiting special cases. We prove the consistency of Kolmogorov-Cramér estimators in the (expected) L1-norm by direct technique employing domination relations between statistical distances. In our numerical simulation we illustrate the quality of consistency property for sample sizes of the most practical range from n = 10 to n = 500. We study dependence of consistency in L1-norm on ϵ-contamination neighborhood of the true model and further the robustness of these two newly defined estimators for normal families and contaminated samples. Numerical simulations are used to compare statistical properties of the minimum Kolmogorov–Cramér, generalized Cramér–von Mises, standard Kolmogorov, and Cramér–von Mises distance estimators of the normal family scale parameter. We deal with the corresponding order of consistency and robustness. The resulting graphs are presented and discussed for the cases of the contaminated and uncontaminated pseudo-random samples.
On Boundary Layer Problems Exhibiting Resonance

We consider singularly perturbed boundary value problems for differential equations of the form $\varepsilon y'' + f(x;\varepsilon )y' + g(x,\varepsilon )y = h(x,\varepsilon )$, where f changes sign at one or more points in the interval under consideration. Such points are sometimes referred to as turning points. We show that various anomalies can occur in such problems. One of these anomolies is the phenomenon of resonance. We present criteria for resonance to occur, and derive uniformly valid asymptotic expansions for the solution of such problems.
Quasielastic Light Scattering in the Broadband Brillouin Spectra of Relaxor Ferroelectric PbMg1/3Nb2/3O3

In this paper, the behavior of quasielastic light scattering (QELS) in a PbMg1/3Nb2/3O3 (PMN) crystal under broadband Brillouin light scattering in a temperature range from 750 K to 80 K was studied. It was shown that QELS consists of two components: narrow (0.9 GHz to 11 GHz) and wide (80 GHz to 600 GHz). The dependencies of the intensity, I, of these components on the frequency, ν, are well described by the power law I ~ eνα, with different α, and are determined by the distribution of the relaxation times. The analysis of the Brillouin spectra showed that the behavior of the relaxation time of both the components of QELS with temperature change is well described by the Arrhenius law. Additionally, in the vicinity of the intermediate temperature T* ≈ 380 K, a critical relaxation time behavior for the narrow component of QELS was detected. In the vicinity of the same temperature, a maximum in the integral intensity of both the components of QELS was observed, which is adjacent to another maximum in the region of the Vogel–Fulcher temperature TVF ≈ 250 K corresponding to the transformation of the crystal to a nonergodic state.
The Impact of Physical Exercise on Obesity in a Cohort of Southern Italian Obese Children: Improvement in Cardiovascular Risk and Immune System Biomarkers

Background: Childhood obesity (CO) is a serious medical condition affecting approximately 120 million children and adolescents worldwide. It is characterized by a persistent inflammatory state with inflammatory markers overexpressed, which in turn leads to a higher cardiovascular risk. It is well known that physical exercise reduces the inflammatory state in obese children. In the present study, we evaluated various biochemical parameters in obese children performing physical exercise compared to a group of obese sedentary children. Hence, the objective is to identify a panel of biomarkers to prevent numerous obesity-related complications. Methods: We examined two populations: 44 sedentary obese children (OSe), recruited on 5 November 2018 from Santobono–Pausilipon Children’s Hospital, Naples (Italy) of age = 11 ± 3.3 and 30 obese children who practice sport (OSp) of age = 10 ± 2.5. We observed a significant variation in some biochemical parameters such as white blood cells, C-reactive protein (CRP), glycemia and insulinemia. Moreover, we determined the levels of interleukins, chemokines and defensins by ELISA assay. Results: Our results showed a reduction in serum level of glycemia (p-value < 0.001), neutrophils (p-value < 0.05) and CRP (p-value < 0.05), whereas no relevant variations have been reported in insulin levels. Moreover, we found a decrease in serum levels of PDGF-β (p-value < 0.05), IL-9 (p-value < 0.01), IL-6 (p-value < 0.0001), IL-8 (p-value < 0.0001), IP-10 (p-value < 0.01), Eotaxin (p-value < 0.0001) and GM-CSF (p-value < 0.01) in OSp population in comparison to OSe. At the same time, we did not observe any significant variation in serum levels of IL-1ra and IL-17 between the two populations. On the other hand, we found an increase in HNP-1 (p-value < 0.0001) and HBD1 (p-value < 0.01) in OSp if compared to OSe. Conclusions: This study shed light on the role of physical exercise on CO, demonstrating in our population that an early evaluation of some biochemical parameters could be an assumption to prescribe physical exercise in order to monitor and prevent childhood obesity and related disorders.
A Pair of Resonant Planets Orbiting GJ 876

Precise Doppler measurements during 6 yr from the Lick and Keck observatories reveal two planets orbiting GJ 876 (M4V). The orbital fit yields companion masses of M sin i = 0.56 and 1.89 MJ, orbital periods of P = 30.1 and 61.0 days, semimajor axes of a = 0.13 and 0.21 AU, and eccentricities of e = 0.28 and 0.10, respectively. The orbital periods are nearly in the ratio of 2 : 1, unprecedented among major planets but common among moons and asteroids. Moreover, the axes of the elliptical orbits appear to be nearly aligned. The inner companion was not recognized previously owing to the 2 : 1 ratio of periods, which allowed its signature to masquerade as added orbital eccentricity of the outer planet. Dynamical simulations show that the system is stable within a subset of the observed orbital parameters. The stability may be provided by a mean-motion resonance and the apparent alignment of the major axes. These planets pose unsolved questions about their formation and dynamical evolution, which brought them within 0.08 AU of each other and locked them in resonance.
Ecological Momentary Assessment of Masseter Muscle Activity in Patients with Bruxism

According to the International Bruxism Consensus, bruxism refers to the activity of the masticatory muscles reflecting contraction disorders, regardless of whether it is during sleep (SB) or an awake (AB) state. The objective of the present study was to evaluate the activity of the masseter muscle by surface electromyographic (sEMG) recordings. This study was performed on 20 participants with self-reported “possible bruxism” (study group) and 20 participants with no self-reported bruxism (control group); all participants underwent an evaluation of the masseter muscle activity using the dia-BRUXO device, which provides numerical parameters regarding sEMG (the total duration and the type of bruxism specific events, the effort made by the masticatory muscles during the recording period, and the personal bruxism index of each participant). Participants from the study group presented more clenching events during AB, three times more frequent than the control group (p = 0.002, Mann–Whitney U test); for SB, the frequency of clenching and grinding events was comparable within the study group, being more frequent than for the control group; the mean value of the effort index was higher for AB (1.177%) than SB (0.470%) and the same for the duration index, with a mean value of 2.788% for AB and 1.054% for SB. All participants from the control group presented reduced values for all acquired parameters. Overall, the personal bruxism index in AB was approximately four times higher for the study group (2.251%) compared to the control group (0.585%) (p < 0.005, Mann–Whitney U test). Similar values were obtained for SB. All participants with “possible bruxism” from the study group presented a higher activity of the masseter muscle, which is specific for bruxism, thus being defined as “definite bruxism”.
Column densities of interstellar molecular hydrogen

Equivalent widths of some 50 lines in the 0-0 to 5-0 Lyman bands of H2 are reported in the spectra of 28 stars. Curves of growth are given and column densities for levels from J = 0 to J = 5 are tabulated, with a few values and upper limits for N(6) and N(7), together with values for b, the velocity spread parameter. In three Orion stars and in rho Leo pairs of components are detected, the difference in radial velocity is determined, and column densities are measured or estimated; tentative identifications are made with the components observed by Hobbs (1969) in the Na D-lines. Column densities for HD are given for 13 stars. Upper limits for column densities in the first and second vibrational levels are listed for several stars; the ratio of N(J = 0) in the v double prime = 1 level to that in the ground vibrational level is less than 2.4 x 10 to the minus 8th power in zeta Oph. Values of a rotational excitation temperature for the higher J levels are given for all the stars. Data are presented which show an apparent increase of velocity dispersion with J for a number of stars, as measured both from the curves of growth and from line widths.
High β-Glucans Oats for Healthy Wheat Breads: Physicochemical Properties of Dough and Breads

Bread is a highly consumed food whose nutritional value can be improved by adding an oat flour (Avena sativa L.-variety Bonaerense INTA Calen-Argentina) to a high-industrial quality wheat flour (Triticum aestivum L.). This cultivar of oat contains high amounts of β-glucans, which act as a prebiotic fiber. Wheat flour was complemented with different amounts of oat flour (5, 15, and 25%). A contribution of hydrophilic components from oat flour was evident in the oat–wheat mixtures. At the same time, the high content of total dietary fiber led to changes in the rheological properties of the dough. Mixtures with a higher proportion of oats showed an increase in alveographic tenacity (stiffer dough), higher stability, and a lower softening degree in farinographic assays. The dough showed significant increases in hardness and gumminess, without significant changes in cohesiveness, i.e., no disruption to the gluten network was observed. Relaxation tests showed that the blends with a higher oat content yielded 10 times higher stress values compared to wheat dough. Analysis of the oat–wheat breads showed improvements in nutritional parameters, with slight decreases in the volume and crust color. The crumb showed significant increases in firmness and chewing strength as the amount of oats added increased. Nutritional parameters showed that lipids, dietary fiber, and β-glucans were significantly increased by the addition of oats. Sensory analysis achieved high response rates with good-to-very good ratings on the hedonic scale set. Thus, the addition of oats did not generate rejection by the consumer and could be accepted by them. Breads with wheat and oats showed nutritional improvements with respect to wheat bread, since they have higher dietary fiber content, especially in β-glucans, so they could be considered functional breads.
Numerical Model of the Double-Pipe System with Protective Layer

Abstract Nowadays, higher performance is being sought in newly built power plants. The efficiency of power plants is mainly achieved by maximizing the steam parameters. Consequently, ever more expensive high-alloy steels are being used. For this reason, design concepts, in which high efficiency with lower investment costs are becoming increasingly popular. Such an innovation is the double-pipe system with a protective coating, which provides thermal insulation for the primary pipe in which the supercritical steam flows. This pipe is also cooled by an external flow by the steam with lower parameters. The article presents the developed two-dimensional numerical model. The use of the Galerkin method enables the complete transient analysis of a double-pipe system to be carried out, considering temperature-dependent material properties. The numerical model was compared with the computational fluid dynamics model. The temperature gradient in the inner pipe wall with and without coating was determined. In addition, the response of the wall temperature to a change in steam temperature was investigated. As observed, the protective layer can improve boiler performance characteristics when applied to thick-walled boiler components. It can also enable the use of less demanding steel.
Design of Dual ISM Bands Low Power Rectenna for Indoor Wireless Power Transfer Application

The paper concentrates on the design of a dual-band rectenna which consists of a receiving antenna, impedance matching, single-stage voltage doubler rectifier as well as a load. The rectenna is designed using HSMS 280C Schottky diodes as its main component and combined with the lumped elements, microstrip lines as well as quasi-Yagi with semi-bowtie as the driven element. The quasi-Yagi antenna with a semi-bowtie driven element is designed using Computer Simulation Technology (CST) and its Touchstone file is imported into the Advanced Design System (ADS) for simulation with the other components of the rectenna. The rectenna with an input power of −6dBm has an optimal Power Conversion Efficiency (PCE) of 32.1% while receiving a signal from the ISM 0.868GHz band transmitter and 18.8% using the input power of −7dBm at ISM 0.915GHz band. Both PCEs are obtained using 700Ω and 900Ω as load and producing minimum output voltage (Vo) of 0.3V and 0.28V respectively. The rectenna operates in both Industrial, Scientific, and Medical (ISM) 0.868GHz and 0.915GHz bands since both are unlicensed bands. The ISM 0.868GHz band is normally used in Europe while ISM 0.915 GHz band is widely used in the United States as well as Japan. The dual-band rectenna can be used for powering a power management unit such as EM8500 or AEM30300 in an indoor environment.
Diffraction of Antiplane Shear Waves by a Finite Crack

The scattering of polarized harmonic shear waves by a sharp crack of finite length under antiplane strain is considered. Use is made of integral transforms, which reduce the problem to the evaluation of a system of coupled integral equations. Special emphasis is placed on obtaining the detailed structure of the crack‐front stress and displacement fields, which control the instability behavior of cracks in brittle materials. While the dynamic stresses around the singular crack point are found to be qualitatively the same as those encountered under statical loading, they differ quantitatively in that the intensity of the dynamical stress field, which may be regarded as a measure of the force tending to cause crack propagation, depends on the incident wavelength. At certain wavelengths, this intensification is shown to be larger than the static case. The method of solution in this paper applies equally well to boundary value problems in electromagnetic and acoustic theory.
Testing for Parameter Restrictions in a Stationary VAR Model: A Bootstrap Alternative

This paper proposes the use of the bootstrap when the system Wald test is employed to test for linear restrictions in a stationary vector autoregressive (VAR) model. The bootstrap test is conducted using the estimated generalised least square estimator for VAR parameters, which considers contemporaneous correlations among the error terms. It is found that the bootstrap test shows little size distortion in small samples. In contrast, the asymptotic Wald test exhibits serious size distortion, severely over-rejecting the true null hypothesis in small samples. The bootstrap test also has desirable power properties, with its power particularly high when the model is near non-stationary and the error terms are highly correlated contemporaneously. As an application, the bootstrap Wald test is employed to test for the predictability of stock return from dividend yield using U.S. data.
Pullback V-attractors of the 3-dimensional globally modified Navier-Stokes equations

The existence and finite fractal dimension of a pullback attractor in the space $V$ for a three dimensional system of the nonautonomous Globally Modified Navier-Stokes Equations on a bounded domain is established under appropriate properties on the time dependent forcing term. These equations were proposed recently by Caraballo et al and are obtained from the Navier- Stokes Equations by a global modification of the nonlinear advection term. The existence of the attractor is obtained via the flattening property, which is verified.
Mechanism of the Middle Ear

A mechanical model of the middle ear is obtained from anatomical observations. The differential equations for the model are solved, and the solutions are found in good agreement with the impedance of the ear at the tympanic membrane measured in many earn of fresh cadavers. Thus, the mechanism of the middle ear is clarified theoretically as well as experimentally. The ossicular chain loaded with the impedance of the cochlea is found to be the most important factor controlling the impedance of the tympanic membrane. The ossicular chain has two resonances: the lower one due to the malleoincudal body, and the higher due to the stapes. Thus, the ossicular chain keeps the reactance of the tympanic membrane near or at its resonances. The function of the air cavities behind the tympanic membrane is found to be similar to but less than that of the ossicular chain. The apparent pressure gain by the middle ear for the cochlea is measured. From these data the frequency characteristic of the ossicular chain the impeda.