Miracle-dz/UniFAR-FTUs huggingface dataset:
Journal of Symbolic Computation

Kalman varieties of tensors are algebraic varieties consisting of ten- sors whose singular vector k -tuples lay on prescribed subvarieties. They were ﬁrst studied by Ottaviani and Sturmfels in the context of matrices. We extend recent results of Ottaviani and the ﬁrst author to the partially symmetric setting. We describe a generating func- tion whose coeﬃcients are the degrees of these varieties and we analyze its asymptotics, providing analytic results à la Zeilberger and Pantone. We emphasize the special role of isotropic vectors in the spectral theory of tensors and describe the totally isotropic Kalman variety as a dual variety. © 2022 The Author(s
Evolution of cell resistance, threshold voltage and crystallization temperature during cycling of line-cell phase-change random access memory

Doped SbTe phase change (PRAM) line cells produced by e -beam lithography were cycled 100 million times. During cell cycling the evolution of many cell properties were monitored, in particular the crystalline and amorphous resistance, amorphous resistance drift exponent, time-dependent threshold voltage, threshold voltage as a function of RESET pulse height, crystallization temperature, and activation energy of crystal growth. The power of the present approach is that all these properties were measured simultaneously during the life of single cells. The evolution of the cell properties can be summarized by (i) an initialization phase characterized by settle-in effect of the material surrounding the programmable region, (ii) a usable life phase where initially the cell properties remain fairly constant until after (cid:2) 5 (cid:3) 10 5 cycles decomposition of the programmed region caused degradation of the cell properties, and (iii) ﬁnally an end of life phase where the cell is stuck in the SET state after typically 10 8 cycles. Although generally the threshold voltage is directly related to the amorphous resistance it was found that during cycling this relation is not constant but evolved as well. Instead, the crystallization temperature could be linked to the threshold voltage throughout the complete life cycle of the cell which could lead to new insights to the nature of the threshold event. V C 2011 American Institute of Physics . [doi:10.1063/1.3603025]
A class of singular integral equations

where (P) indicates Cauchy's principal value. This equation is related to a problem of aerodynamics. The case k (x, y) = 0 was first solved by Fuchs-Hopf-Seewald (cί. G. Hamel [1H p. 145) employing Fourier series expansions. Subsequently K. Schroder [3] gave a beautiful solution with the aid of conjugate functions. The author [4] have ever given a solution of CD following to Schloder's method. Recently we have been able to see some periodicals published during the war, and learned that Professor E. Reissner £2] has already solved an integral equation of the type (1). But his method seems to be analogous to Fuchs-Hopf-Seewald, and the solution is given by its Fourier series. In this paper we give a method to solve the equation CD, which is different from that of Reissner and gives an easier solution in some cases. We shall begin with a reciprocal formula of conjugate functions. Let H(β) be even and G(θ) be odd, then we have
Coronal loop formation resulting from photospheric convection

We have demonstrated the dynamic formation of coronal magnetic loops in three dimensions as a result of horizontal vortex-like convection on the photosphere. Localized plasma motions twist bipolar magnetic field lines which are tied to the dense photosphere by high electrical conductivity. The twists propagate into the corona along the field and create a narrow quasi-toroidal region where the field lines interwind. At the same time, this tubeline region rises in altitude, expands in cross section, and distorts into a slight S shape before settling into an equilibrium state. The MHD stability of such line-tied magnetic loop structures is directly exhibited by this dynamic simulation.
Correlation between luminescence and structural properties of Si nanocrystals

Strong room-temperature photoluminescence (PL) in the wavelength range 650–950 nm has been observed in high temperature annealed (1000–1300 °C) substoichiometric silicon oxide (SiOx) thin films prepared by plasma enhanced chemical vapor deposition. A marked redshift of the luminescence peak has been detected by increasing the Si concentration of the SiOx films, as well as the annealing temperature. The integrated intensity of the PL peaks spans along two orders of magnitude, and, as a general trend, increases with the annealing temperature up to 1250 °C. Transmission electron microscopy analyses have demonstrated that Si nanocrystals (nc), having a mean radius ranging between 0.7 and 2.1 nm, are present in the annealed samples. Each sample is characterized by a peculiar Si nc size distribution that can be fitted with a Gaussian curve; by increasing the Si content and/or the annealing temperature of the SiOx samples, the distributions become wider and their mean value increases. The strong correlation betw.
CO-to-H2 Conversion Factor in Galaxies

A general method and formulae to derive the CO-to-H2 conversion factor in galaxies as a function of the metallicity are presented based on an analysis of the observed data for the conversion factor obtained for nearby spiral and dwarf irregular galaxies. From the CO data for eight galaxies we obtained the following formula, which gives the conversion factor (X*) as a function of metallicity: logX* = -1.0 (12 + logO/H) + A, where X* = NH2/IQO X 10~20 H2/(K km s _1) and A is a constant. Since the metallicity is dependent on the luminosity of galaxies, we derived a correlation between the conversion factor and the absolute magnitude of galaxies. We also investigated dependence of the conversion factor on the distance from the center of individual galaxies. We also present a formula to calculate X* as a function of the radius in a galaxy.
Generator of variable gas flows using an isothermal chamber

There is no effective method to calibrate the dynamic characteristics of gaseous flow meters. This is because the density of these fluids changes largely with respect to the variation in both pressure and temperature. The present paper describes the development of an unsteady mass flow generator for gases. The generator consists of an isothermal chamber and two spool-type servo valves. The heat transfer area within the isothermal chamber is made sufficiently large by stuffing the copper wool materials to ensure that the essential isothermal conditions are preserved. The calibration of the dynamic characteristics of the gaseous flow meters and the internal flows within such meters are achieved using the generator. Experimental tests reveal that the generator can control oscillatory flows at a frequency of up to 50 Hz with an uncertainty of 5.5%. In addition, the unsteady mass flow generator can generate flows for more than 30 min. Thus, the effectiveness of the generator is demonstrated.
On a complementarity problem in Banach space

The paper gives a result on the existence and uniqueness of solutions for the complementarity problems associated with hemicontinuous monotone mappings of convex cones. We correct the assumptions and proof given in an earlier paper of A. T. Dash and S. Nanda [A complementarity problem in mathematical programming in Banach space, J. Math. Anal. Appl. 98 (1984), 328-331].
Extremal climatic states simulated by a 2-dimensional model Part I: Sensitivity of the model and present state

The criterion, based on the thermodynamics theory, that the climatic system tends to extremizesome function has suggested several studies. In particular, special attention has been devotedto the possibility that the climate reaches an extremal rate of planetary entropy production.Due to both radiative and material effects contribute to total planetary entropy production, climatic simulations obtained at the extremal rates of total, radiative or material entropy productionappear to be of interest in order to elucidate which of the three extremal assumptionsbehaves more similar to current data. In the present paper, these results have been obtainedby applying a 2-dimensional (2-Dim) horizontal energy balance box-model, with a few independentvariables (surface temperature, cloud-cover and material heat fluxes). In addition, climaticsimulations for current conditions by assuming a fixed cloud-cover have been obtained. Finally, sensitivity analyses for both variable and fixed cloud models have been carried out.
Effects of varying Smagorinsky constant on simulating post-flashover fires

Air flow post-flashover room fire is weakly compressible. In this paper, Navier–Stokes equations in an appropriate form will be applied to simulate such motion. Large eddy simulation (LES) is used with the Smagorinsky sub-grid scale model. A pool fire was described by the combustion model based on simple and fast chemical reaction. Three-dimensional simulations were carried out by using different values of Smagorinsky sub-grid scale constant. Predicted results on air temperatures and radiative heat fluxes were compared with the experimental values. Results illustrated that the value of the Smagorinsky constant would affect the simulations for strong buoyant plume. Value of the Smagorinsky constant from 0.20 to 0.21 appears to be reasonable in simulating flashover with a filter width of 0.1 m.
A new modified Reynolds equation for ultrathin film gas lubrication

A new modified Reynolds equation for solving the ultrathin film gas lubrication is proposed to overcome the complicated and time-consuming difficulties of solving the linearized Boltzmann equation. The model equation is based on modified high-order slip-flow velocity distribution with three adjustable coefficients, which are corrected according to the Boltzmann model. The results are compared to those obtained using other kinds of currently employed modified Reynolds equations. It shows that the present model produces a closer approximation to that of the exact Boltzmann model than do other models, in a wider range of inverse Knudsen number. In addition, the newly derived equation is widely applicable to practical use.
High precision atomic physics

Accurate atomic collision and structure data are an essential ingredient for a wide range of research fields as well as for major technological applications. Areas from laboratory physics to quantum processing, from plasma research applications in nuclear fusion to lighting research, as well as astrophysics and cosmology, depend critically on such data. But many data still exhibit inconsistencies and inaccuracies, so that significant efforts are continuing to improve the data quality. Additionally, a substantial body of much-needed data is absent from the published literature and from databases. Appreciable progress is being made, aided by greatly improved, or even entirely new, laboratory equipment and by vastly expanded computer power, which has made possible the development of greatly refined atomic structure codes. Thus in recent years, atomic data have not only become more accurate, but the body of data has also greatly increased, highly ionized species and complex heavy atoms have been addressed, fully relativistic treatments have been developed, and new energy and frequency ranges have been explored. This special issue focuses on many of these new sophisticated theoretical and experimental approaches that have made high precision atomic physics a reality. On the experimental side, several contributions cover the area of highly charged ions, where accurate measurements have become possible mainly due to the availability of electron beam ion traps (EBITs) and the utilization of storage rings. Studies of QED effects in Li-like ions, determinations of atomic lifetimes and precision wavelength measurements of highly charged ions are discussed. Furthermore, two contributions illustrate the extremely high precision of spectroscopic measurements for heavy ions and atoms, and two fundamental investigations address a new search for the electric dipole moment of the electron and measurements of the anapole moment in Fr and Rb. On the theoretical side, the contributions demonstrate that new, expanded and refined atomic structure and electron-impact collision codes are successfully applied to complex atomic systems, such as highly charged ions and heavy atoms, using increasingly full relativistic treatments.
Coupled initialization in an ocean–atmosphere tropical cyclone prediction system

A coupled ocean–atmosphere dynamical ensemble prediction system is used to study coupled initialization and bred cyclic modes in the case of Tropical Cyclone (TC) Yasi. Ocean initial perturbations are constructed to identify the fastest‐growing nonlinear modes in the ocean response to the TC. The ensemble provides a characterization of how initial and evolving dynamical ocean perturbations influence the coupled system through surface fluxes under extreme conditions. Results show how sea‐surface temperature perturbations project into atmospheric perturbations of pressure and moisture content within the storm environment. By calculating the local bred vector dimension for ocean‐surface velocity, we show that a low‐dimensional subspace forms along the track of TC Yasi. The iterative approach to coupled initialization used in this study generates cyclic modes that are embedded on to the dynamics of regions critical to the coupled ocean–atmosphere TC dynamics. The ensemble mean forecasted sea‐surface temperature and sea‐surface height associated with the ocean response is in better agreement with observations, despite the biases the coupled model inherits from its component models. Both model and observations reveal a twin cold core structure in the ocean wake of TC Yasi.
Ethers and esters as alternative fuels for internal combustion engine: A review

Ether and ester fuels can work in the existing internal combustion (IC) engine with some important advantages. This work comprehensively reviews and summarizes the literatures on ether fuels represented by DME, DEE, DBE, DGM, and DMM, and ester fuels represented by DMC and biodiesel from three aspects of properties, production and engine application, so as to prove their feasibility and prospects as alternative fuels for compression ignition (CI) and spark ignition (SI) engines. These studies cover the effects of ether and ester fuels applied in the form of single fuel, mixed fuel, dual-fuel, and multi-fuel on engine performance, combustion and emission characteristics. The evaluation indexes mainly include torque, power, BTE, BSFC, ignition delay, heat release rate, pressure rise rate, combustion duration, exhaust gas temperature, CO, HC, NOx, PM, and smoke. The results show that ethers and esters have varying degrees of impact on engine performance, combustion and emissions. They can basically improve the thermal efficiency of the engine and reduce particulate emissions, but their effects on power, fuel consumption, combustion process, and CO, HC, and NOx emissions are uncertain, which is due to the coupling of operating conditions, fuel molecular structure, in-cylinder environment and application methods. By changing the injection strategy, adjusting the EGR rate, adopting a new combustion mode, adding improvers or synergizing multiple fuels, adverse effects can be avoided and the benefits of oxygenated fuel can be maximized. Finally, some challenges faced by alternative fuels and future research directions are analyzed.
A Phylogenetic Assessment of Nematodes (Oxyuroidea: Pharyngodonidae) Infecting Moroccan Lizards

Summary Molecular tools can be used to estimate the phylogeny of species and to identify cryptic diversity, but their use for parasites has lagged behind that of free-ranging organisms. As an example, in North Africa there is minimal molecular data available for helminth parasites of lizards. In this work we used two molecular markers (the nuclear 18S rRNA and the mitochondrial Cytochrome c Oxidase subunit 1) to investigate the diversity of nematodes of the family Pharyngodonidae parasitizing three genera of lizards from Morocco (Chalcides, Quedenfeldtia and Tarentola) and to explore their co-evolutionary history. Morphological assessments indicated that members of three genera were present: Spauligodon, Thelandros, and Parapharyngodon. Phylogenetic analysis of 18S rRNA sequences indicated the monophyly of the genus Spauligodon, and that some lineages could be distinguished, including Spauligodon auziensis from the host species Tarentola mauritanica, and another unnamed lineage from hosts of the genus Chalcides. However, with this slow-evolving marker some species could not be distinguished. The genus Thelandros was not monophyletic, although relationships were not strongly supported. Analysis of the faster evolving mitochondrial marker clearly separated various species of Spauligodon, as well as distinct unnamed lineages identified in the host genus Chalcides and the host Quedenfeldtia moerens.
The Synthesis of UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine Kinase (GNE), α-dystroglycan, and β-galactoside α-2,3-sialyltransferase 6 (ST3Gal6) By Skeletal Muscle Cell As a Response To Infection with Trichinella Spiralis

Summary The Nurse cell of the parasitic nematode Trichinella spiralis is a unique structure established after genetic, morphological and functional modification of a small portion of invaded skeletal muscle fiber. Even if the newly developed cytoplasm of the Nurse cell is no longer contractile, this structure remains well integrated within the surrounding healthy tissue. Our previous reports suggested that this process is accompanied by an increased local biosynthesis of sialylated glycoproteins. In this work we examined the expressions of three proteins, functionally associated with the process of sialylation. The enzyme UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) is a key initiator of the sialic acid biosynthetic pathway. The α-dystroglycan was the only identified sialylated glycoprotein in skeletal muscles by now, bearing sialyl-α-2,3-Gal-β-1,4-Gl-cNAc-β-1,2-Man-α-1-O-Ser/Thr glycan. The third protein of interest for this study was the enzyme β-galactoside α-2,3-sialyltransferase 6 (ST3Gal6), which transfers sialic acid preferably onto Gal-β-1,4-GlcNAc as an acceptor, and thus it was considered as a suitable candidate for the sialylation of the α-dystroglycan. The expressions of the three proteins were analyzed by real time-PCR and immunohistochemistry on modified methacarn fixed paraffin tissue sections of mouse skeletal muscle samples collected at days 0, 14 and 35 post infection. According to our findings, the up-regulation of GNE was a characteristic of the early and the late stage of the Nurse cell development. Additional features of this process were the elevated expressions of α-dystroglycan and the enzyme ST3Gal6. We provided strong evidence that an increased local synthesis of sialic acids is a trait of the Nurse cell of T. spiralis, and at least in part due to an overexpression of α-dystroglycan. In addition, circumstantially we suggest that the enzyme ST3Gal6 is engaged in the process of sialylation of the major oligosaccharide component of α-dystroglycan.
Discovery of a New Genus and Species of Allocreadiidae (Trematoda) in Mexico: Mesoamericatrema Magnisacculus n. Gen. n. Sp

Summary The trematodes of Allocreadiidae are mainly parasites of freshwater fish and the family contains 18 valid genera. Since 2004, 4 genera have been described in the Americas: Paracreptotrema, Paracreptotrematoides, Pseudoparacreptotrema and Auriculostoma, of which the latter was recently synonymized with Creptotrema by Franceschini et al., (2021). During a study in 2018 on fish parasites of Lacantún River, Chiapas, Mexico, allocreadiids were collected from the intestine of Atherinella alvarezi and morphological differences with other genera of the family were immediately noted. These differences were corroborated with molecular data and phylogenetic analyses, which indicated that it was a new genus and species. The objective of this study is to describe the new taxon, which we name Mesoamericatrema magnisacculus n. gen., n. sp. as well as to clarify its phylogenetic relationships, host specificity, and geographical distribution. For this, we carried out a meticulous study of the morphology and compared the new taxon with its congeners. We also obtained sequences of the 28S and ITS from the ribosomal RNA region that were used in generating molecular phylogenies and in calculating genetic distances with sequences of other species of Allocreadiidae available in the Genbank. The new genus is mainly characterized by having a very large cirrus sac in relation to the length of its body and nests in a clade that groups Creptotrema, Creptotrematina, Paracreptotrema, Paracreptotrematoides, Pseudoparacreptotrema and Wallinia, all of which have a Neotropical affinity in terms of their geographic and host distribution. Mesoamericatrema n. gen. is the fifth genus of Allocreadiidae to be described in the Americas since 2004, the third discovered in Mexico since 2016, and the first to be described as parasitizing Atheriniformes, which indicates that Middle America is a region where important speciation events have occurred in freshwater fish parasites.
Sleep disturbances in nurse managers during the early and late stages of the COVID-19 pandemic

Introduction Working conditions during the COVID-19 pandemic have affected health professionals’ quality of sleep. To date, most of the studies that assess the impact of the COVID-19 pandemic on sleep have been carried out with front-line health personnel, and almost none of them have been carried out with managers. Objective To evaluate the quality of sleep and the level of stress in nurse managers during the early and late stages of the COVID-19 pandemic. Methods Cross-sectional studies were carried out at two time points: after the lockdown period (July 2020) and a year and a half after the start of the pandemic (October 2021). A total of 102 nurse managers of a tertiary hospital were invited to participate. The Perceived Stress Scale (PSS-14) and Pittsburgh Sleep Quality Index (PSQI) were administered to assess stress levels and sleep quality. Results The response rate was 85.2% in 2020 and 81.3% in 2021. Nursing managers showed alterations in sleep quality throughout the pandemic: 70.1% after confinement and 61.4% at the beginning of the second wave. In addition to stress, the fear of contagion by COVID-19 influenced sleep problems. More than a year after the start of the pandemic, the professionals’ fear of contagion decreased. Perceived stress also decreased, but sleep disturbances remained. Conclusion High stress and poor sleep quality among nurse managers require special attention, and specific interventions need to be implemented. Hospitals should develop programs that help nurse managers develop skills to mitigate stress levels and thus improve sleep quality and professional quality of life.
Cyberbullying victimization among adolescencts: results of the International self-report delinquency study 3

ABSTRACT The study is based on a wide international research study, the International Self-Report Delinquency Study 3 (ISRD-3), with the aim of understanding if there is a relationship between having lived traumatic intrafamily experiences and potentially being a victim of cyberbullying. The data have been collected by a questionnaire ISRD-3 administered to a 20 European country sample of 57.463 students from 7th to 9th grade. Results show a statistically significant relationship between traumatic intrafamilial experiences such as a serious illness of one of the parents, episodes of violence suffered and assisted, separation or divorce of the parents, and being victimized in adolescence of cyberbullying.