Miracle-dz/UniFAR-FTUs huggingface dataset:
Long-term stellar variability

Abstract Stars with significant subsurface convection zones develop magnetic loop structures that, arising from the surface upward to the external atmospheres, cause flux variability detectable throughout the whole electromagnetic spectrum. In fact, diagnostics of magnetic activity are in radio wavelengths, where gyrosincrotron radiation arises from the quiescent and flaring corona; in the optical region, where important signatures are the Balmer lines, the Ca ii IRT and H&K lines; in the UV and X ray domains, the latter mainly due to coronal thermal plasma. The zoo of different magnetic features observed for the Sun – spots, faculae, flares, CMEs – are characterized by different temporal evolution and energetics, both in quantity and quality. As a consequence, the time scale of variability, the amount of involved energy and the quality of the involved photons are used as fingerprints in interpreting the observed stellar variability in the framework of the solar-stellar analogy. Here I review main results from long-term multiwavelength observations of cool star atmospheres, with emphasis to similarities and differences with the solar case.
Effect of Process Parameters on Material Removal Rate and Surface Characteristics in WEDM Machining of Titanium Grade 7 Alloy

Wire Electrical Discharge Machining (WEDM) is a modern machining technique. WEDM is electro-thermal non-conventional machining processes follow to cut very hard materials. WEDM is non-traditional material cutting operation employed to machine complex geometries and shapes. The present paper attempts to study surface and sub-surface variations during WEDM of titanium grade 7 alloy with Brass wire coated with Zn. This paper presents experimental studies with varying three key process parameters viz. pulse ON time (TON), pulse OFF time (TOFF), peak current (IP). The investigation is focused on assessment of material removal rate, surface roughness as well as recast layer. Scanning electron Microscope (SEM) examinations are carried out on surface textures and are discussed in the article. The obtained results indicated that the stretched pulse time discharges more energy causes rough surface finish. The MRR is also strongly influenced by TON.
Keap1-Nrf2 Heterodimer: A Therapeutic Target to Ameliorate Sickle Cell Disease

Sickle cell disease (SCD) is a monogenic inheritable disease characterized by severe anemia, increased hemolysis, and recurrent, painful vaso-occlusive crises due to the polymerization of hemoglobin S (HbS)-generated oxidative stress. Up until now, only four drugs are approved for SCD in the US. However, each of these drugs affects only a limited array of SCD pathologies. Importantly, curative therapies, such as gene therapy, or hematopoietic stem cell transplantation are not available for every patient because of their high costs, availability of donor matching, and their serious adverse effects. Therefore, there is an unmet medical need for novel therapeutic strategies that target broader SCD sequelae. SCD phenotypic severity can be alleviated by increasing fetal hemoglobin (HbF) expression. This results in the inhibition of HbS polymerization and thus sickling, and a reduction in oxidative stress. The efficacy of HbF is due to its ability to dilute HbS levels below the threshold required for polymerization and to influence HbS polymer stability in RBCs. Nuclear factor-E2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein-1 (Keap1)-complex signaling is one of the most important cytoprotective signaling controlling oxidative stress. Nrf2 is present in most organs and, after dissociation from Keap1, it accumulates in the cytoplasm, then translocates to the nucleus where it binds to the antioxidant response element (ARE) sequences and increases the expression of various cytoprotective antioxidant genes. Keeping this in mind, various researchers have proposed a role of multiple agents, more importantly tert-Butylhydroquinone (tBHQ), curcumin, etc., (having electrophilic properties) in inhibiting keap1 activity, so that Nrf2 can translocate to the nucleus to activate the gamma globin gene, thus maintaining alpha-hemoglobin-stabilizing protein (AHSP) and HbF levels. This leads to reduced oxidative stress, consequently minimizing SCD-associated complications. In this review, we will discuss the role of the Keap-1–Nrf2 complex in hemoglobinopathies, especially in SCD, and how this complex might represent a better target for more effective treatment options.
Model for thermal conductivity in nanoporous silicon from atomistic simulations

Riccardo Dettori,1 Claudio Melis,1 Xavier Cartoixà,2 Riccardo Rurali,3 and Luciano Colombo1,* 1Dipartimento di Fisica, Università di Cagliari, Cittadella Universitaria, I-09042 Monserrato (Ca), Italy 2Departament d’Enginyeria Electrònica, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain 3Institut de Ciència de Materials de Barcelona (ICMAB-CSIC) Campus de Bellaterra, 08193 Bellaterra, Barcelona, Spain (Received 7 August 2014; revised manuscript received 24 November 2014; published 23 February 2015)
Rhizosphere Fungal Dynamics in Sugarcane during Different Growth Stages

Understanding the normal variation of the sugarcane rhizosphere fungal community throughout its life cycle is essential for the development of agricultural practices for fungal and ecological health associated with the microbiota. Therefore, we performed high-throughput sequencing of 18S rDNA of soil samples using the Illumina sequencing platform for correlation analysis of rhizosphere fungal community time series, covering information from 84 samples in four growth periods. The results revealed that the sugarcane rhizosphere fungi possessed the maximum fungal richness in Tillering. Rhizosphere fungi were closely associated with sugarcane growth, including Ascomycota, Basidiomycota, and Chytridiomycota, which showed high abundance in a stage-specific manner. Through the Manhattan plots, 10 fungal genera showed a decreasing trend throughout the sugarcane growth, and two fungal genera were significantly enriched at three stages of sugarcane growth (p < 0.05) including Pseudallescheria (Microascales, Microascaceae) and Nectriaceae (Hypocreales, Nectriaceae). In addition, soil pH, soil temperature, total nitrogen, and total potassium were critical drivers of fungal community structure at different stages of sugarcane growth. We also found that sugarcane disease status showed a significant and strong negative effect on selected soil properties by using structural equation modeling (SEM), suggesting that poor soil increases the likelihood of sugarcane disease. In addition, the assembly of sugarcane rhizosphere fungal community structure was mainly influenced by stochastic factors, but after the sugarcane root system became stable (Maturity), the stochastic contribution rate decreased to the lowest value. Our work provides a more extensive and solid basis for the biological control of sugarcane potential fungal diseases.
A hybrid kinetic WENO scheme for inviscid and viscous flows

In this paper, we propose a high‐order finite volume hybrid kinetic Weighted Essentially Non‐Oscillatory (WENO) scheme for inviscid and viscous flows. Based on the WENO reconstruction technique, a hybrid kinetic numerical flux is introduced for the present method, which includes the mechanisms of both the free transfer and the collision of gas molecules. The collisionless free transfer part of the hybrid numerical flux is constructed from the conventional kinetic flux vector splitting treatment, and the collision contribution is considered by constructing an equilibrium gas state and calculating the corresponding numerical flux at the cell interface. The total variation diminishing Runge–Kutta methods are used for the temporal integration. The high‐order accuracy and good shock‐capturing capability of the proposed hybrid kinetic WENO scheme are validated by many numerical examples in one‐dimensional and two‐dimensional cases. Copyright © 2015 John Wiley & Sons, Ltd.
A new class of wide-band microstrip arrays

Wide-band microstrip antennas are still a challenge and in the last couple of years a number of new configurations have been reported. Most of these configurations are multilayer patch antennas with some of them achieving up to 40% in bandwidth. Recently, another new geometry has been reported, a single patch fed by a three-dimensional feed line, which in essence is a very tall patch fed by a wide-band dipole. This antenna is reported to exhibit a 90-100% bandwidth for VSWR <2:1; towards the high end of the band, however, the radiation from the wide-band dipole is too strong and interferes with the patch pattern resulting in a high crosspolarization level. In the array environment, though, the crosspolarization is reduced by the array factor. The paper analyzes the performance of an eight-element array and its scanning capabilities. To avoid grading lobes the radiating elements have to be very close to each other, so the impact of the mutual coupling is also investigated.
Investigating Sport Stakeholders’ Understanding of Behaviour Management within a Competitive Youth Baseball Team

The following study employed an instrumental case study to investigate sport stakeholders’ understandings of behavioural management strategies used in competitive youth baseball, including the identification of common strategies and interpretations of these as punishment or discipline. Twenty-one participants, from one competitive (AAA) all-boys baseball team, including three coaches, eleven baseball players, and seven parents, were recruited to participate in an individual semi-structured interview. Interviews ranged between 30 and 150 min, and data were analyzed using reflexive thematic analysis. Several behaviour management tactics were identified, of which exercise, benching and yelling negative comments were most often reported. While participants interpreted excessive exercise and benching as punitive and/or disciplinary approaches to behavioural management, yelling was consistently viewed as punitive. Participants confused punishment and discipline as interchangeable, thus suggesting a lack of awareness regarding developmentally appropriate strategies of behavioural management and highlighting the normalization of certain punitive tactics in youth sport. The results underscore the necessity of imparting knowledge to the sports community regarding age-appropriate behavioural management interventions to foster safe and enjoyable athletic experiences for youth competitors.
Advancing time-frequency clustering techniques for multichannel blind source separation and source number estimation

The success of blind source separation systems relies on its ability to handle adverse realworld conditions, and audio applications of blind source separation systems are often faced with the cocktail party problem of multiple simultaneously active speakers. The convolutive nature of the mixing of the source signals and the relative number of the microphones and source signals also add to the di culty of the blind source separation problem. This thesis focuses on the sparseness-based time-frequency masking approach for under-determined blind source separation. In particular, we direct our attention upon the automatic estimation of time-frequency masks based on the full-band clustering of spatial features as extracted from the microphone observations. We explore recent advances of full-band clustering-based techniques to blind source separation and investigate and extend an existing technique termed the multiple sensors degenerate unmixing estimation technique (MENUET). We modify the MENUET by using an alternative clustering scheme for mask estimation, the fuzzy c-means, and present comprehensive evaluations in a range of environments to establish its feasibility. We then explore two extensions to the fuzzy c-means: firstly, the estimation of reliability weights for the spatial features, and secondly the inclusion of contextual information into the clustering objective function. This thesis also investigates other full-band clustering techniques such as the Gaussian mixture model and Watson mixture model for mask estimation. We evaluate and compare the performance of all the full-band clustering techniques in this thesis, and conclusions are drawn as to which are the most robust for a variety of both simulated and real-world conditions, including international benchmark data sets. Finally, to remove any requirement on a priori knowledge on the number of source signals, we consider two novel approaches to source number estimation. The first uses an adaptive optimization scheme based on the fuzzy c-means clustering algorithm, whilst the second approach considers the full-band clustering of speech activity sequences with the Watson mixture model.
Development and Optimization of a Mechanically Robust Novel Rotor Topology for Very-High-Speed IPMSMs

Due to the trade-off between rotor mechanical strength and magnetic leakage, the high-speed capability of interior permanent magnet machines (IPMSM) is severely limited. This paper proposes a novel rotor topology capable of delivering 5 kW at 100,000 rpm using commercialized electrical steel laminations. By implementing the mechanical analysis in an iterative evolution process, two promising new topologies were developed. The first topology uses smooth compound curves (CC) to minimize the stress concentration and will be referred to as CC-type; the second topology is developed based on the CC-type with the aim to strengthen the structure further using the concept of a double-tied arch bridge (DAB) and referred as the DAB-type henceforward. After comparing the designs obtained from a detailed multiphysics optimization process, the DAB-type design was found to outperform the CC-type in all aspects, especially the mechanical robustness. This design was selected for experimental verification and a prototype was constructed. The mechanical and electromagnetic performances of the design were fully verified experimentally. The DAB-type prototype has achieved 2.31 × 105 rpm√kW, which is 1.5 times higher than other laminated rotor high-speed IPMSM designs found in the literature.
A comparison of methods for inverting helioseismic data

L'utilisation des frequences observees de l'oscillation solaire pour etudier les proprietes de la structure interne du Soleil necessite l'application de techniques d'inversion efficaces et precises. Comme contribution a l'evaluation systematique des techniques d'inversion appliquees aux problemes helioseismologiques, on presente les moyens permettant une comparaison unifiee des schemas d'inversions lineaires en termes de leurs resolutions et proprietes d'erreurs. Cette approche est ensuite appliquee a 4 techniques couramment utilisees, pour 3 ensembles de modes differents representatifs des donnees helioseismologiques
Stochastic modeling and performance analysis in balancing load and traffic for vehicular ad hoc networks: A review

The rapid growth of vehicular applications has resulted in high demand for Internet technology, which demands an unprecedented network capacity and a high quality of service (QoS). In vehicular ad hoc networks (VANETs), since nodes (vehicles) are highly mobile. The dynamic nature of the network topology in the VANET system changes due to frequent changes in link connectivity. The vehicles‐to‐vehicles (V2V), vehicles‐to‐infrastructure (V2I), and QoS, as well as the heterogeneity of applications within the VANET. VANETs have been introduced to make driving comfortable by providing safety and support to drivers. Due to the flexibility and offloading schemes available in‐vehicle applications, there are some limitations. However, there are many issues in providing optimum service provisioning and scheduling in the vehicular environment. In VANETs, BSs and roadside units (RSUs) improve QoS. However, Internet services transmit packets to vehicles using stochastic models, and it predicts the traffic on a VANET. We provide open challenges to drive stochastic models in this direction.
Metastable phases in interface controlled materials

Metastable phases may be stabilized at interfaces due to lower surface or interface energies in comparison with the equilibrium phase. An example for this kind of stabilization effect is the phenomenon of surface melting, where a liquid-like film forms at the surface below the actual melting point. The excess energy necessary for the formation of the metastable, undercooled liquid phase is overcompensated by the gain in surface energy. Similar effects have been found in interface controlled materials such as thin films or nanocrystalline materials. In thin films, incoherent interfaces between the film and the underlying substrate contribute significantly to the total energy. The lower interface energy of a metastable film can stabilize the non-equilibrium phase as in the case of surface melting. A study is reviewed of thin Fe(Zr) alloy films which serves as a model system for the investigation of the interface effects. If deposited on suitable substrates, these films grow in the amorphous phase whereas in bulk materials the crystalline solid solution is more stable. Crystallization of the initially amorphous films sets in at a critical thickness where the driving force for crystallization can overcome the stabilizing effect of the interface. Under the experimental conditions, diffusional transport is negligible so that no phase separation can occur. Upon increasing the solute concentration, a polymorphic crystal-to-glass transformation (CGT) is encountered in the volume at a critical solute concentration. At concentrations close to the CGT, the relative stabilities of the competing phases, i.e. the crystalline solid solution and the amorphous alloy, approach each other. Therefore, the chemical composition of the films plays a role equivalent to the temperature in the case of surface melting. In the vicinity of the CGT, the interface energy contributions may dominate phase formation. As a result, a dramatic increase of the critical thickness for crystallization is observed with increasing solute concentration. A thermodynamic model based on the competing energetic contributions can explain the results. A generalized phase diagram is used for the description of interface effects in glass forming systems. Precursor effects like wetting at interfaces close to the conditions for phase transitions in bulk materials are also expected to be significant in systems with a high density of incoherent interfaces. The interfaces may serve as nucleation centres which play an important role for phase transformations in these materials.
Derivation of a contact law between a free fluid and thin porous layers via asymptotic analysis methods

We describe the asymptotic behaviour of an incompressible viscous free fluid in contact with a porous layer flow through the porous layer surface. This porous layer has a small thickness and consists of thin channels periodically distributed. Two scales are present in this porous medium, one associated to the periodicity of the distribution of the channels and the other to the size of these channels. Proving estimates on the solution of this Stokes problem, we establish a critical link between these two scales. We prove that the limit problem is a Stokes flow in the free domain with further boundary conditions on the basis of the domain which involve an extra velocity, an extra pressure and two second-order tensors. This limit problem is obtained using Γ-convergence methods. We finally consider the case of a Navier–Stokes flow within this context.
Population decline will likely become a global trend and benefit long-term human wellbeing

Summarising earlier publications, I draw a rather optimistic picture of the human future on this planet, if priority is given to universal education, and, in particular, to female education. The benefits of a greater focus on education range from a lower desired family size and empowerment to reach this goal, to better family health, to poverty reduction, to greater resilience, to expanded capacities to mitigate and adapt to climate change, and, ultimately, to the emergence of better institutions and social values that are less obsessed with material consumption and violent nationalism and more concerned with cooperation, care and wellbeing. I also show that extended periods of below replacement level fertility are beneficial for long-term human wellbeing, and that the human population is on the path to peaking during the second half of this century and then declining to 2–4 billion people by 2200. As this smaller population will be well-educated, they should be healthy and wealthy enough to be able to cope fairly successfully with the already unavoidable (moderate) effects of climate change.
Distribution Estimates Consistent in χ2-Divergence

For a class of histogram based distribution estimators it is proved the consistency in χ2-divergence and expected χ2-divergence. For one of these estimators, introduced formerly by Barron, is also evaluated the rate of consistency in the expected χ2-divergence. These results are stronger than similar results formerly established in the literature for the total variation and Kullback's discrimination information, which are divergences dominated by the χ2-divergence.
Examining transportation mode changes during COVID-19 in Toyama, Japan

ABSTRACT Although the coronavirus disease of 2019 arguably changed citizens’ transportation mode choices, how these choices changed and what factors influenced them, especially during the soft intervention period, remains ambiguous. To clarify this phenomenon, this study examined how citizens’ socio-demographic and psychological factors contributed to their transportation mode changes (public transportation, active transportation: walking and cycling, and cars) between 2019 and 2020. We employed the extended theory of the norm activation model and the value–attitude–behaviour hierarchy, surveyed 973 citizens in Toyama City, Japan, and applied a confirmatory factor analysis and a multinomial logistic regression model. Regarding psychological characteristics, the findings showed that those with positive attitudes toward public transportation tended to shift to public transportation; those with high personal norms for car use tended to shift to public transportation; those with perceived behavioural control over car use tended not to change to public transportation; and those with positive attitudes toward car use tended not to shift to active transportation. Socio-demographically, respondents who were female, highly educated and/or whose income decreased from the previous year tended to shift to active transportation. Age was not significantly associated with transportation mode changes. No significant variable was found between respondents’ shift to cars and socio-demographic and psychological factors. Our study provides implications, suggesting that policymakers focus on adopting measures to retain female or highly educated individuals in the active transportation mode use even beyond the pandemic period, while raising awareness among men, informing them of the health benefits of the active transportation mode and establishing active transportation mode-friendly infrastructure.