Miracle-dz/UniFAR-FTUs huggingface dataset:
An Ultrasonic Transducer with Gaussian Radial Velocity Distribution

In materials evaluation applications requiring the interrogation of modified far field patterns of an ultrasonic transducer, it is desirable to use a transducer which produces a beam with a Gaussian profile. A transducer with a velocity profile which is Gaussian as a function of radius and independent of angle is described. The transducer has been constructed by depositing a circularly symmetric metallic multi-electrode array on a 19.1 mm diameter xcut quartz disk. Each electrode is independently connected to an impedance network optimized to produce the Gaussian distribution with less than two percent maximum error. A computer aided electrode design and calibrated three dimensional interferometric optical and ultrasonic measurements of the far field distribution are presented
Photoluminescence of gamma-, proton- and alpha-irradiated LiF detectors

Lithium fluoride (LiF), one of the most pervasive alkali halides in optical device research, is routinely used in optical data storage and radiation protection. LiF crystals may contain different aggregate defects produced by several types of ionizing radiation, with the number of defects being proportional to the cumulative radiation dose. Stimulation of irradiated LiF detectors by heating or with blue light causes thermoluminescence (TL) or photoluminescence (PL), respectively. We developed a new PL reader equipped with a blue light-emitting diode for stimulation and a Hamamatsu photomultiplier for registering green emissions, dedicated to examining LiF detectors as well as more broadly investigating TL/PL emission from standard LiF detectors irradiated with gamma rays, 60 MeV protons and alpha particles. The results confirmed very high efficiency PL signal from alpha-irradiated LiF detectors corresponding to their low efficiency after gamma irradiation, and vice versa for TL readout. Combining the TL and PL readouts permits us to discriminate between how different kinds of radiation affect efficiency in LiF detectors.
FM and IM intermodulation distortions in directly modulated single-mode semiconductor lasers

Intermodulation distortion in directly-modulated semiconductor lasers is described with the aid of a nonlinear differential equation for the photon density. Both frequency modulation (FM) and intensity modulation (IM) have been investigated. Curves are presented of the magnitudes of the intermodulation products relative to the carriers intensity. Second order distortions are also reported. The comparison of the Bessel function analysis and the perturbation method is quite successful. Finally, laser's FM and IM modulation characteristics are compared, and these theoretical results show that distortion levels would be stronger in FM than in direct IM, when the same operating conditions are adopted. >
Number of states with given spin J of n fermions in a j orbit

A recursion formula for the number of states with a given value of total spin J of n identical fermions in a j orbit, N(J,j,n), is derived. That number is expressed in terms of the number of states with some values of J, of n,n-1, and n-2 fermions in a (j-1) orbit. This formula may be used in calculating N(J,j,n). In this paper the formula is used to prove some interesting results that were found empirically by Zhao and Arima.
Patch near-field acoustical holography in cylindrical geometry

Spatial discrete Fourier transform-based near-field acoustical holography is known to suffer from windowing effects since the measurement aperture is necessarily finite. The latter effect can be mitigated by using patch holography, in which the measured field is extended beyond the measurement aperture based on successive smoothing operations. In this article, the application of a patch holography algorithm to cylindrical geometries is described. In planar geometry, initial zero-padding can be applied to the hologram pressure to an arbitrary degree in both in-plane directions since the pressure magnitude is expected to limit ultimately towards zero in both directions. In a cylindrical geometry, zero-padding can be implemented axially in the same way, but the number of zeros added in the circumferential direction is necessarily determined by the angular sample spacing owing to the periodic nature of the field in this direction. By using both numerical simulation and experimental results, it is shown that t.
Structured semidefinite programs and semialgebraic geometry methods in robustness and optimization

In the first part of this thesis, we introduce a specific class of Linear Matrix Inequalities (LMI) whose optimal solution can be characterized exactly. This family corresponds to the case where the associated linear operator maps the cone of positive semidefinite matrices onto itself. In this case, the optimal value equals the spectral radius of the operator. It is shown that some rank minimization problems, as well as generalizations of the structured singular value ($mu$) LMIs, have exactly this property. In the same spirit of exploiting structure to achieve computational efficiency, an algorithm for the numerical solution of a special class of frequency-dependent LMIs is presented. These optimization problems arise from robustness analysis questions, via the Kalman-Yakubovich-Popov lemma. The procedure is an outer approximation method based on the algorithms used in the computation of hinf norms for linear, time invariant systems. The result is especially useful for systems with large state dimension. The other main contribution in this thesis is the formulation of a convex optimization framework for semialgebraic problems, i.e., those that can be expressed by polynomial equalities and inequalities. The key element is the interaction of concepts in real algebraic geometry (Positivstellensatz) and semidefinite programming. To this end, an LMI formulation for the sums of squares decomposition for multivariable polynomials is presented. Based on this, it is shown how to construct sufficient Positivstellensatz-based convex tests to prove that certain sets are empty. Among other applications, this leads to a nonlinear extension of many LMI based results in uncertain linear system analysis. Within the same framework, we develop stronger criteria for matrix copositivity, and generalizations of the well-known standard semidefinite relaxations for quadratic programming. Some applications to new and previously studied problems are presented. A few examples are Lyapunov function computation, robust bifurcation analysis, structured singular values, etc. It is shown that the proposed methods allow for improved solutions for very diverse questions in continuous and combinatorial optimization.
Numerical solution of magnetohydrodynamics effects on a generalised power law fluid model of blood flow through a bifurcated artery with an overlapping shaped stenosis

This paper presents a numerical analysis of blood flow in a diseased vessel within the presence of an external magnetic field. The blood flow was considered to be incompressible and fully developed, in that the non-Newtonian nature of the fluid was characterised as a generalised power law model for shear-thinning, Newtonian, and shear-thickening fluids. The impact of a transverse directed external magnetic field on blood flow through a stenosed bifurcated artery was investigated. The arterial geometry was considered as a bifurcated channel with overlapping shaped stenosis. The problem was treated mathematically using the Galerkin Least-Squares (GLS) method. The implementation of this numerical method managed to overcome the numerical instability faced by the classical Galerkin technique when adopted to a highly viscous flow. The benefit of GLS in circumventing the Ladyzhenskaya-Babuška-Brezzi (LBB) condition was utilized by evaluating both the velocity and pressure components at corner nodes of a unstructured triangular element. The non-linearity that emerged from the convective terms was then treated using the Newton-Raphson method, while the numerical integrals were computed using a Gaussian quadrature rule with six quadrature points. The findings obtained from this study were then compared with available results from the literature as well as Comsol multiphysics software to verify the accuracy and validity of the numerical algorithms. It was found that the application of magnetic field was able to overcome flow reversal by 39% for a shear-thinning fluid, 26% for a Newtonian fluid, and 27% for a shear-thickening fluid. The negative pressure and steep wall shear stress which occurs at the extremities of an overlapping stenosis throat were diminished by rise in magnetic intensity. This prevented thrombosis occurrence and produced a uniform calm flow.
Statistical Properties of the Big Blue Bump in Active Galactic Nuclei

The shape is the most important characteristic of the big blue bump (bbb). By employing the sample from Walter & Fink, and supplementing it with medium energy X-ray data, we have been successful in separating the bbb component from the nonthermal component for the soft X-ray region and thus obtaining the cutoff energy Ecut of the big bump in the XUV region. Our sample contains 30 type I Seyfert galaxies, which is the largest sample size for the determination of the bbb shape. Statistical analyses show a significant anticorrelation between the spectral UV index (buv) and Ecut. The thermal emission mechanisms for the bbb include the optically thick thermal radiation from the accretion disk (and its corona region), the optically thin thermal free-free radiation and other models. The statistical properties between buv and Ecut, provide an important base for picking and improving a mechanism.
The role of the arts in enhancing data literacy: A scoping review protocol

Data literacy has been defined as “the ability to read, work with, analyze and argue with data”. The United Nations has highlighted a growing risk of inequality for people excluded from the new world of data by lack of education, language, poverty, and discrimination and has called for the development of data literacy at all levels of society. Responses to data are shaped by personal, social and cultural influences, as well as by trust in the source. The arts can play an important role in regulating our responses to information and increasing accessibility, engagement and sense-making of data. However, to our knowledge, to date, there has been no comprehensive review of publications on the role of the arts in the context of data literacy. This paper presents a protocol and a methodological framework to perform a scoping review to identify and map the available evidence for the role of the arts in enhancing data literacy. The review aims to provide an overview of research over the past twenty years to develop a clearer understanding of (a) which art forms are represented in the literature (b) which population groups and settings are identified (c) and the rationale for using the arts to enhance data literacy.
The relationship between rural information consumption and regional economic development with spatial Durbin model—A case study of Zhejiang, China

Information consumption is a kind of economic activity that directly or indirectly takes information products and information services as consumption objects. Most of the existing studies have established the "formula” of rural information consumption in promoting economic and social development, while few efforts have been devoted to study the quantitative reciprocities between them. Therefore, this study aims to investigate the relationship between information consumption in rural areas and regional economic development with a case study of Zhejiang, China. Based on rural information consumption-related indexes, basic geographic data, and other publicly available regional economic development related data, we conduct the exploration with the spatial Durbin model (SDM). The study indicates that (1) from the perspective of spatial analysis, the economic development level of all prefecture-level cities in Zhejiang, China has a significant positive spatial correlation; (2) in rural areas, the network infrastructure improvement, information industry clustering, etc. can accelerate enhancing information consumption and promote regional economic development; and (3) facilitate the development of rural information consumption is conducive to alleviate the imbalance of regional economic development. It is hoped that our study can help understand the current situation of information consumption in rural China and provide a theoretical reference for rural economic and social development.
The Discovery of Nonthermal Radio Emission from Magnetic Bp--Ap Stars

In a VLA survey of chemically peculiar B- and A-type stars with strong magnetic fields, five of the 34 stars observed have been identified as 6 cm continuum sources. Three of the detections are helium-strong early Bp stars (Sigma Ori E, HR 1890, and Delta Ori C), and two are helium weak, silicon-strong stars with spectral types near A0p (IQ Aur = HD 34452, Babcock's star = HD 215441). The 6 cm luminosities L6 (ergs/s Hz) range from log L6 = 16.2 to 17.9, somewhat less than the OB supergiants and W-R stars. Three-frequency observations indicate that the helium-strong Bp stars are variable nonthermal sources.
Efficacy and safety of vapocoolant spray for vascular puncture in children and adults: A systematic review and meta-analysis

Objective The aim was to evaluate the effectiveness and safety of the vapocoolants for vascular puncture in children and adults. Method The search was carried out in PubMed, Web of Science, Embase and The Cochrane Library, from inception to March 2022. Randomized controlled trials comparing vapocoolants to control conditions for participants received intravenous cannulation or arterial puncture were included. Two reviewers independently performed selection of studies, data extraction, and assessment of risk of bias. The analysis was performed using fixed or random-effects model with mean differences or standardized mean difference and risk ratios. Results A total of 25 studies involving 3143 participants were included. Compared with control conditions, vapocoolants may not decrease the pain of patients with arterial puncture (SMD = -0.36, 95% CI = -0.92 to -0.19, P = 0.20), but may more effectively relieve pain for adults received vein puncture (SMD = -0.65, 95% CI = -0.85 to -0.45, P < 0.00001). The application of vapocoolant increased the procedural difficulty of medical personnel (RR = 2.49, 95% CI = 1.62 to 3.84, P<0.000 1) and participants were more willing to use the spray in the future (RR = 1.88, 95% CI = 1.34 to 2.64, P = 0.0002). There was no significant difference for the first attempt success rate of the procedure and the occurrence of adverse events. Conclusions Vapocoolant spray may relieve pain in adults received vein puncture and cannot cause severe side effects, but is ineffective in children. It also had no effect on patients with arterial puncture. In addition, the application of spray increases procedural difficulties for medical professionals, but does not decrease first attempt success rate, and many patients would like to use the spray again for pain relief in the future. Thus, more rigorous and large-scale studies are needed to determine its effectiveness in vascular access.
Stochastic Dynamics and Learning Rules in Layered Neural Networks

The perceptron is a typical feedforward neural network model which has capability of pattern recognition. The learning rule for the perceptron and its convergence was shown by Rosenblatt! ) and Block) A typical perceptron has three layers and the connections between the second and third layers are modified by an error-correcting learning rule. Minsky and Papert analyzed the perceptron and showed its limitations. ) Recently the PDP group proposed a learning rule to change the connections between the first layer and the second layer besides those between second and third layers. ) Thereafter complicated problems have been sucessfully solved by the networks. ) In their model, the output of each cell is expressed by a semilinear activation function of the weighed sum of the inputs through the connections. The connections are changed to decrease an error function. The learning rule is called 'back propagation of error' algorithm. Both the input-output relation and the learning rule are deterministic in their model. We propose two kinds of stochastic models in this paper. In the first model, the input-output relation is probabilistic. This model is similar to the Boltzmann machine),6) but the connections are not symmetric like the Boltzmann machine. So this model is an intermediate model between the perceptron and the Boltzmann machine. The other model uses a stochastic dynamics for the learning rule. In the deterministic model the system may encounter some local minima of an error function and it means that the problem cannot be solved. In the stochastic model the local minima can be got over with thermal noises, and it becomes possible to approach the correct solution by the simulated annealing technique. )
Parental gambling frequency and adolescent gambling: A cross-sectional path model involving adolescents and parents

Introduction Nowadays, most of the research studies in the field of adolescent gambling are focused on individual factors related to problem gambling. The aim of this study was to test an integrated model to explain adolescent problem gambling involving both individual (i.e., correct gambling knowledge, superstitious thinking, and gambling-related cognitive distortions) and environmental factors (i.e., parental gambling frequency). In detail, the aim was to better understand the role of parental gambling behavior on adolescents’ gambling frequency and problem gambling severity, to draw indications for prevention. Methods Participants were 680 parents (36% men; Mage = 48.32, SD = 6.14 years) of 680 high school students (51% boys; Mage = 15.51, SD = .55 years) attending the second year of different high schools in Tuscany (Italy). Data collection occurred within the school prevention program PRIZE (Prevention of gambling risk among adolescents). Results A path model showed was conducted to detect direct and indirect effects from individual and environmental factors to gambling problem severity. Analyses showed that correct gambling knowledge and superstitious thinking were directly related–respectively in a negative and a positive direction–both to gambling-related cognitive distortions and adolescents’ gambling frequency. Parental gambling frequency was directly associated with adolescents’ gambling frequency. Correct gambling knowledge and superstitious thinking were indirectly related to adolescents’ gambling problem severity through the mediational role of gambling-related cognitive distortions and gambling frequency. Parental gambling frequency was indirectly linked to gambling problem severity by passing through adolescents’ gambling frequency. Conclusions The current cross-sectional results confirm that parental gambling behavior has an important role for adolescents’ gambling behavior and severity. Thus, results highlight the need for innovative prevention programs which involve adolescents’ adult reference figures and integrate the individual risk and protective factors with the environmental ones.
Availability and Use of Essential Opioid Analgesics in Sub-Saharan Africa: A Scoping Review Protocol

Introduction: The treatment of acute, peri-operative, and chronic pain by healthcare practitioners and health systems requires appropriate access to and availability of essential opioid medications. While opioids are often oversupplied and overprescribed in high-income countries, there are significant inequities as many low- and middle-income countries (LMICs) experience severe shortages. In fact, while the richest 10% in the world reside in countries receiving almost 90% of all available opioids, 50% of the poorest in the world reside in countries receiving just 1% of all available opioids. Understanding the social, economic, cultural, and regulatory barriers to access essential opioid analgesics in LMICs is critical in delineating and prioritizing appropriate interventions. We aim to conduct a scoping review on the availability and usage of essential opioid analgesics in LMICs, specifically in sub-Saharan Africa, to identify barriers, themes, and knowledge gaps. Materials and Methods: We will utilize the framework for conducting scoping reviews by Arksey and O’Malley. We will perform the search for articles in 3 electronic databases (i.e., SCOPUS, PubMed, Embase) and relevant gray literature. Only articles in English will be included. There will be no restriction on the publication period. All articles will directly involve either the availability and/or the use of essential opioid analgesics. Studies will be restricted to focus on sub-Saharan Africa. We will use a tailored extraction frame to extract relevant information from published articles that meet our inclusion criteria. We will analyze the data using both descriptive statistics and thematic analysis on the main study questions. Ethics and Dissemination: Since we will not be collecting primary data, formal ethical approval is not required. Our study findings will be disseminated through abstracts, conference presentations, and peer-reviewed publications. Highlights 50 percent of the poorest in the world reside in countries receiving just 1 percent of all available opioids There is a paucity of data analyzing the inequitable distribution of essential opioid analgesics worldwide Our scoping review will identify barriers, themes, and knowledge gaps on the availability and use of essential opioids in SSA It will identify areas for further research and potential policy initiatives
Increase in the extent of mass coral bleaching over the past half-century, based on an updated global database

The recurrence of mass coral bleaching and associated coral mortality in the past few decades have raised questions about the future of coral reef ecosystems. Although coral bleaching is well studied, our understanding of the spatial extent of bleaching events continues to be limited by geographical biases in data collection. To address this gap, we updated a previous observational database and spatially modelled the probability of past bleaching occurrence. First, an existing raw observational database was updated to cover the 1963–2017 period using searches of the academic and grey literature and outreach to coral reef monitoring organizations. Then, in order to provide spatially-explicit global coverage, we employed indicator kriging to spatially model the probability of bleaching occurrence each year from 1985 through 2017 at 0.05° x 0.05° lat-long resolution. The updated raw database has 37,774 observations, including 22,650 positive bleaching reports, three times that in the previous version. The spatial interpolation suggests that 71% of the world’s coral reefs likely (>66% probability) experienced bleaching at least once during the 1985 and 2017 period. The mean probability of bleaching across all reefs globally was 29–45% in the most severe bleaching years of 1998, 2005, 2010 and 2016. Modelled bleaching probabilities were positively related with annual maximum Degree Heating Weeks (DHW), a measure of thermal stress, across all years (p<0.001), and in each global bleaching event (p<0.01). In addition, the annual maximum DHW of reef cells that very likely (>90% probability) experienced bleaching increased over time at three times the rate of all reef cells, suggesting a possible increase in reef thermal tolerance. The raw and spatially interpolated databases can be used by other researchers to enhance real-time predictions, calibrate models for future projections, and assess the change in coral reef response to thermal stress over time.