Miracle-dz/UniFAR-FTUs huggingface dataset:
Turbulent Generation of Intracluster Magnetic Fields and Faraday Rotation Measurements

Statistical analysis of relatively large samples of Faraday rotation measurements of radio sources seen through clusters of galaxies recently led Kim, Tribble, & Kronberg to conclude that magnetic fields of microgauss strength were present in clusters of galaxies. Expanding the analysis, we have checked these samples for the possible effects of Galactic contamination, of a selection bias due to inclusion of cluster sources into the test sample, and of cooling flows. We find no statistically significant evidence that the seemingly loose selection criteria affected the results. Through comparisons of the likely spatial distributions of the fields and relativistic electrons, detailed relations are obtained between field values derived from Faraday rotation, and combined ratio and high-energy X measurements
The host galaxies of radio-loud AGN: mass dependencies, gas cooling and AGN feedback

The properties of the host galaxies of a well-defined sample of 2215 radio-loud AGN with redshifts 0.03 10^23 W/Hz is a strong function of stellar mass, rising from nearly zero below a stellar mass of 10^10 Msun to more than 30% at 5x10^11 Msun. The integral radio luminosity function is derived in six ranges of stellar and black hole mass. Its shape is very similar in all of these ranges and can be well fitted by a broken power-law. Its normalisation varies strongly with mass, as M_*^2.5 or M_BH^1.6; this scaling only begins to break down when the predicted radio-loud fraction exceeds 20-30%. There is no correlation between radio and emission line luminosities for the radio-loud AGN in the sample and the probability that a galaxy of given mass is radio-loud is independent of whether it is optically classified as an AGN. The host galaxies of the radio-loud AGN have properties similar to those of ordinary galaxies of the same mass. All of these findings support the conclusion that the optical AGN and low radio luminosity AGN phenomena are independent and are triggered by different physical mechanisms. Intriguingly, the dependence on black hole mass of the radio-loud AGN fraction mirrors that of the rate at which gas cools from the hot atmospheres of elliptical galaxies. It is speculated that gas cooling provides a natural explanation for the origin of the radio-loud AGN activity, and it is argued that AGN heating could plausibly balance the cooling of the gas over time. [Abridged]
Edgeworth and saddlepoint approximations in the first-order noncircular autoregression

SUMMARY The first-order noncircular autoregressive model is considered and Edgeworth and saddlepoint approximations are given for the distribution of the least squares estimator of the autoregressive coefficient. Numerical calculations are used to compare the two approximations with the exact distribution, found by numerical integration. Both approximations are unsatisfactory when the autoregressive coefficient is moderately large and the sample size small, the saddlepoint because it is undefined in the tail area, and the Edgeworth because it badly distorts tail area probabilities. When the sample size is larger, the saddlepoint approximation performs well and is capable of three decimal place accuracy, although it is still not available in tail areas when the autoregressive coefficient is large.
Relationship between the development of musculoskeletal disorders, physical activity level, and academic stress among undergraduates students of University of Nigeria

BACKGROUND: Academic stress is a common experience among university students. It can affect the body composition of the students through behavioral changes, which further affect their physical activity level (PAL). Musculoskeletal disorders could arise from the interaction of these factors. This study aimed to determine the relationship between PAL, academic stress, selected anthropometric indices, and the development of MSDs among a selected Nigerian population. MATERIALS AND METHODS: This was a cross-sectional study of 256 (129 females and 127 males) undergraduates of the University of Nigeria, Enugu Campus aged 15–30 years using Student's Stress Inventory to evaluate academic stress, the short-form of the International Physical Activity Questionnaire to determine the PAL, and a Standard Nordic Musculoskeletal Questionnaire to assess MSDs. RESULTS: The results showed a high PAL with the male students having more PAL (61.4%) than female students. Secondly, the prevalence of MSDs among the population was high (66.02%) and the students faced moderate academic stress with the prevalence being more among the female students (75.2%). A significant difference was observed between academic stress and the development of MSDs (P = 0.009). CONCLUSION: This study's findings support the hypothesis that increased academic stress and low level of physical activity are linked to increased risks of MSDs among students. Thus, it is warranted that the University curriculum is re-adjusted and incorporate public enlightenment programs on possible causes and prevention of musculoskeletal disorders, stress management, and coping strategies.
Two Layer Magnetodielectric Metamaterial with Enhanced Dielectric Constant as a New Ferrite Like Material

In this study, we present large enhancement of effective dielectric constant of magnetodielectric metamaterials made from two layers of parallel periodic non-magnetized iron wires embedded inside dielectric (wax), in two orientations of them, relative to the incident electromagnetic field. This kind of enhancement is predicted by finite difference time domain (FDTD) method electromagnetic simulations made for infinite size metamaterials of same unit cell and same electromagnetic wave's geometry of incidence. In this model, the complex internal constants were estimated from the calculated complex S-parameters by using Ross–Nicolson method. The validity of our prediction was tested, from comparison of calculated S-parameters with experimental ones measured on a sample made by rapid prototyping, using a modified strip transmission line method. The dielectric enhancement was found to be about 500%, as it was expected from simulations. Applicability of this family of metamaterials to ferrites like applications is discussed.
EFFICIENT CALCULATION OF THE THREE-DIMENSIONAL SOUND PRESSURE FIELD AROUND A NOISE BARRIER

A numerical method is presented for calculating the sound pressure around a noise barrier of constant but arbitrary cross-section. To obtain the exact solution of this problem, the Helmholtz equation must be solved in the three-dimensional domain outside the barrier. It is shown in this article how to calculate this 3-D sound pressure from solutions of simpler problems defined on the two-dimensional domain outside a cross-section of the barrier. The numerical solution of a large three-dimensional problem is thus avoided and the efficiency of the calculation is considerably improved especially when a whole frequency spectrum is needed. By using the boundary element method to calculate the numerical solutions in the two-dimensional domains, examples are given of determinations of sound pressure fields created by a point source and by an incoherent line source. In this way the efficiency of barriers of different cross-sections can be compared by using the real sound pressure around them. From the frequency spectrum at a point, one can then calculate by Fourier transform the temporal variations of the sound pressure created by a noise source moving in a direction parallel to the barrier.
Derivation of polarization from Odin/OSIRIS limb spectra

A new technique for deriving the degree of linear polarization from limb‐scattered sunlight radiance measurements is presented and applied to Odin/OSIRIS. In this technique, the measured OSIRIS grating efficiency spectrum is fit to OSIRIS limb spectra using the differential optical absorption spectroscopy technique and the resultant fitting constant is shown to represent the difference in linear polarization between two tangent heights. The validity of this technique is confirmed using simulations from a vector limb radiative transfer model. OSIRIS scans of the difference in linear polarization from October 2003 are shown to be very sensitive to stratospheric and upper tropospheric aerosols, including background sulphates, clouds, and polar stratospheric clouds.
Finding peace journalism: An analysis of Pakistani media discourse on Afghan refugees and their forced repatriation from Pakistan

This study investigates media coverage of Afghan refugees by English-language media in Pakistan and explores how coverage is shaped by a shift in the political stance of the Pakistani state and establishment towards Afghanistan. The author examines how Afghan refugees, their forced repatriation from Pakistan, and the subsequent conflict between Pakistan and Afghanistan were framed in both long-form and short-form media coverage over three years. Using Galtung’s Peace and War Journalism Model to inform the Critical Discourse Analysis, this study finds that conflict-escalatory frames dominated media coverage, and media stance changed over time to reflect state policy on the forced repatriation of over three million Afghan refugees in Pakistan. Findings reveal that the coverage in all four publications was highly politicized and inflammatory, the voice of Afghan refugees was significantly missing from coverage, while the Pakistani government and military elite were predominantly used as news sources. Based on the findings, the author argues that pressures from the Pakistani state and military establishment are key reasons why media coverage of Afghan refugees frequently contained negative frames of terrorism and ethnonationalism. Sporadic employment of limited peace-oriented framing was, however, observed in some of the coverage.
Numerical simulations of separatrix instabilities in collisionless magnetic reconnection

Electron scale dynamics of magnetic reconnection separatrix jets is studied in this paper. Instabilities developing in directions both parallel and perpendicular to the magnetic field are investigated. Implicit particle-in-cell simulations with realistic electron-to-ion mass ratio are complemented by a set of small scale high resolution runs having the separatrix force balance as the initial condition. A special numerical procedure is developed to introduce the force balance into the small scale runs. Simulations show the development of streaming instabilities and consequent formation of electron holes in the parallel direction. A new electron jet instability develops in the perpendicular direction. The instability is closely related to the electron MHD Kelvin-Helmholtz mode and is destabilized by a flow, perpendicular to magnetic field at the separatrix. Tearing instability of the separatrix electron jet is modulated strongly by the electron MHD Kelvin-Helmholtz mode.
Mechanism of the formation of singularities for diagonal systems with linearly degenerate characteristic fields

For inhomogeneous diagonal system with distinct characteristics or with characteristics with constant multiplicity, under the assumption that the system is linearly degenerate and the $C^1$ norm of the initial data is bounded, we show that the mechanism of the formation of singularities of classical solution to its Cauchy problem must be of ODE type. Similar results are also obtained for corresponding mixed initial-boundary value problems on a semi-unbounded domain.
Noninvasive determinants of pulmonary hypertension in interstitial lung disease

Abstract Pulmonary hypertension (PH) in interstitial lung disease (ILD) is associated with increased mortality and impaired exertional capacity. Right heart catheterization is the diagnostic standard for PH but is invasive and not readily available. Noninvasive physiologic evaluation may predict PH in ILD. Forty‐four patients with PH and ILD (PH‐ILD) were compared with 22 with ILD alone (non‐PH ILD). Six‐min walk distance (6MWD, 223 ± 131 vs. 331 ± 125 m, p = 0.02) and diffusing capacity for carbon monoxide (DLCO, 33 ± 14% vs. 55 ± 21%, p < 0.001) were lower in patients with PH‐ILD. PH‐ILD patients exhibited a lower gas‐exchange derived pulmonary vascular capacitance (GXCAP, 251 ± 132 vs. 465 ± 282 mL × mmHg, p < 0.0001) and extrapolated maximum oxygen uptake (VO2max) (56 ± 32% vs. 84 ± 37%, p = 0.003). Multivariate analysis was performed to determine predictors of VO2 max. GXCAP was the only variable that predicted extrapolated VO2 max among PH‐ILD and non‐PH ILD patients. Receiver operating characteristic curve analysis assessed the ability of individual noninvasive variables to distinguish between PH‐ILD and non‐PH ILD patients. GXCAP (area under the curve [AUC] 0.85 ± 0.04, p < 0.0001) and delta ETCO2 (AUC 0.84 ± 0.04, p < 0.0001) were the strongest predictors of PH‐ILD. A CART analysis selected GXCAP, estimated right ventricular systolic pressure (eRVSP) by echocardiogram, and FVC/DLCO ratio as predictive variables for PH‐ILD. With this analysis, the AUC improved to 0.94 (sensitivity of 0.86 and sensitivity of 0.93). Patients with a GXCAP ≤ 416 mL × mmHg had an 82% probability of PH‐ILD. Patients with GXCAP ≤ 416 mL × mmHg and high FVC/DLCO ratio >1.7 had an 80% probability of PH‐ILD. Patients with GXCAP ≤ 416 mL × mmHg and an elevated eRVSP by echocardiogram >43 mmHg had 100% probability of PH‐ILD. The incorporation of GXCAP with either eRVSP or FVC/DLCO ratio distinguishes between PH‐ILD and non‐PH‐ILD with high probability and may therefore assist in determining the need to proceed with a diagnostic right heart catheterization and potential initiation of pulmonary arterial hypertension‐directed therapy in PH‐ILD patients.
A Search for MgNC and AlNC in TMC-1: The Status of Metals in Dark Cloud Cores

Heavy metals in the gas phase are important in controlling the ionization of a cold dark cloud and hence the chemistry and finally the cloud evolution. Two of us (S. P. and R. C. D.) earlier suggested a fast radiative association mechanism to form MgNC and AlNC in TMC-1. We have conducted a sensitive search with the Green Bank Telescope (GBT) for both species in TMC-1. The upper limit for the fractional abundance of MgNC is 1.2 × 10-11. We have run detailed models of the chemistry, which include high and low metal content, three values of C/O, and three values of density. The models include the time dependence up to 1 × 108 yr. Most of the models predict that we should have seen MgNC. We compare the conditions in TMC-1 with those for IRC +10216, in which MgNC and AlNC are both detected. We conclude that in IRC +10216 the chemistry favors a high abundance of both atomic Mg+ and cyanopolyynes, the two reactants that form MgNC, and that these reactants are less favored in TMC-1.
Transient kinetics of light-induced metastable states in single crystals and aqueous solutions ofNa2[Fe(CN)5NO]∙2H2O

The generation and relaxation of light-induced metastable states at room temperature is investigated in single crystals and aqueous solutions of ${\mathrm{Na}}_{2}[\mathrm{Fe}{(\mathrm{C}\mathrm{N})}_{5}\mathrm{N}\mathrm{O}]∙2{\mathrm{H}}_{2}\mathrm{O}$ (SNP), using transient absorption spectroscopy. The temporal monoexponential decay after exposure to nanosecond laser pulses results from the thermal deexcitation of the metastable state named SII. The lifetime $\ensuremath{\tau}$ of SII at $T=302\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ is $\ensuremath{\tau}=1.8(1)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}7}\phantom{\rule{0.3em}{0ex}}\mathrm{s}$ in single crystals and $\ensuremath{\tau}=1.1(1)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}7}\phantom{\rule{0.3em}{0ex}}\mathrm{s}$ in aqueous solutions. An Arrhenius-like behavior is verified yielding the activation energy ${E}_{A}=0.43(3)\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ and the frequency factor $Z=7\ifmmode\times\else\texttimes\fi{}{10}^{13}\phantom{\rule{0.3em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$. The buildup time of the metastable state SII is faster than $1\phantom{\rule{0.3em}{0ex}}\mathrm{ns}$ and occurs via a singlet excited state. With an exposure of $0.8\phantom{\rule{0.3em}{0ex}}\mathrm{J}∕{\mathrm{cm}}^{2}$, 0.8(2)% of the molecules can be transferred from the ground state to SII.
A study on threshold voltage stability of low operating voltage organic thin-film transistors

A low operating voltage (<2 V) organic field-effect transistor (OFET) using phenylhexyltrichlorosilane (PTS) self-assembled monolayer (SAM) dielectric and copper phthalocyanine (CuPc) as semiconductor with improved mobility (0.035 cm2 V−1 s−1) and threshold voltage stability was demonstrated. This device showed better performance when compared to an OFET with octyltrichlorosilane (OTS-8) SAM dielectric. The improved mobility was attributed to the 2D growth mode of CuPc on PTS SAM because of surface energy matching between the two, whereas CuPc film on OTS-8 showed a 3D growth mode with larger grain boundary density. The higher threshold voltage stability of OFETs on PTS SAM was attributed to the efficient coverage and screening of trap centres at dielectric/semiconductor interface due to stronger intermolecular linking and formation of closely packed surface by the bulky phenyl end groups. Decrease in grain boundaries offered by 2D growth of CuPc for electron and hole trapping was also found to be another reason for improved threshold voltage stability. The results indicated that the nature of the end group of SAM dielectric, surface chemistry of dielectric and initial growth mode of semiconductors are all responsible for improvement in threshold voltage stability and enhanced performance of OFET.
Experimental Investigation of the Natural Vortex Length in Tangential Inlet Cyclones

In this study, the natural vortex length has been investigated experimentally under the effects of inlet gas velocity, diameter, and insertion length of the vortex finder and surface friction in a special designed cyclone which has a double cylindrical body without cone. Experimental results show that, comparing to the other parameters, the height of the frictional surface and inlet gas velocity affect the natural vortex length considerably. The natural vortex length increases with the increase of inlet velocity and with the decrease of the height of the frictional surface. It was also observed that when the diameter of the vortex finder increases, the natural vortex length increases up to certain point and starts to decrease after that.
Broad-band spectroscopy of Hercules X-1 with Suzaku

Hercules X-1 was observed with Suzaku in the main-on state from 2005 to 2010. The 0.4- 100 keV wide-band spectra obtained in four observations showed a broad hump around 4-9 keV in addition to narrow Fe lines at 6.4 and 6.7 keV. The hump was seen in all the four observations regardless of the selection of the continuum models. Thus it is considered a stable and intrinsic spectral feature in Her X-1. The broad hump lacked a sharp structure like an absorption edge. Thus it was represented by two different spectral models: an ionized partial covering or an additional broad line at 6.5 keV. The former required a persistently existing ionized absorber, whose origin was unclear. In the latter case, the Gaussian fitting of the 6.5-keV line needs a large width of sigma = 1.0-1.5 keV and a large equivalent width of 400-900 eV. If the broad line originates from Fe fluorescence of accreting matter, its large width may be explained by the Doppler broadening in the accretion flow. However, the large equivalent width may be inconsistent with a simple accretion geometry.
Self-Regulated Learning and Motivation Among Gifted and High-Achieving Students in Science, Technology, Engineering, and Mathematics Disciplines: Examining Differences Between Students From Diverse Socioeconomic Levels

Self-regulated learning (SRL) is an active process that assists students in managing their thoughts, behaviors, and emotions to navigate their learning experiences successfully. The study examined the differences in motivation and SRL between gifted and high achievers (GHAs) and typical achievers (TAs) in science, technology, engineering, and mathematics (STEM) disciplines by addressing the contribution of socioeconomic status (SES). A sample of 151 students in 11th and 12th grades from two high schools in Israel were divided into four study groups based on their general intelligence, school grades, and SES. Participants completed SRL and motivation questionnaires. The results indicated that among GHAs, all motivation measures were significantly higher than those of TAs, especially among students from low-SES environments. GHA students reported using more SRL strategies than TA students regarding organization, metacognition, time and learning environment, peer learning, and effort regulation. Students from low-SES environments reported using more organization strategies than those from high-SES environments, whereas TA students surpassed their GHA counterparts in critical thinking.
Microstructure fibres for optical sensing in gases and liquids

A novel water-core microstructure fibre design allows nearly ideal guidance for aqueous sensing applications. The total internal reflection by a microstructured silica–air cladding provides robust confinement of light in a fluid-filled core, if the average cladding index is sufficiently below the index of water. Numerical results show dramatically improved loss and overlap of light with the sample, compared to evanescent-field fibres, indicating a direct improvement of sensor performance. A strategy for the improvement of evanescent-wave gas sensors is also discussed.
Ion depletion in the high-latitude exosphere; simultaneous OGO 2 observations of the light ion trough and the VLF cutoff

Simultaneous observations of positive ion composition, VLF earth-to-satellite transmission, and whistlers have been obtained from the OGO 2 satellite during October 1965 in a polar, dawn-dusk orbit. As the satellite moves poleward above about 55° invariant latitude, sudden depletions of the light ion components of the topside ionosphere are observed, wherein the concentrations of H+ and He+ decrease by as much as an order of magnitude within 3°Λ. The light ion trough correlates with similar rapid reductions in the propagation of both man-made and natural VLF signals received at the satellite, where signal intensities are observed to decrease by as much as 20 db and where whistler rates decrease abruptly within 3°Λ. Poleward of the trough, the depleted light ion distributions are characterized by rapid fluctuations in concentration, which appear to correlate in some cases with significant enhancements in the VLF noise level. The combined evidence of the light ion depletion and VLF cutoff further identifies the plasmapause as the often abrupt boundary of the plasmasphere. The abruptness of the light ion trough suggests the possibility that the mechanism responsible for the depletion results under certain conditions in a sharply defined heating and upward expansion of the lower atmosphere. Limited evidence of VLF absorption as well as abrupt increases in neutral density near the trough zone appears consistent with this possibility.
Time-Domain Analysis of Tunability and Modulation Characteristics in Coupled-Ring Reflector Laser Diode

The characteristics of a widely tunable coupled-ring reflector laser diode are studied using a time-domain modeling approach. The coupled-ring reflector is a planar waveguide reflector which does not require distributed Bragg gratings. Instead, the coupled-ring reflector consists of a bus waveguide and two coupled ring resonators coupled to the bus. It is shown that the tuning range can be a few tens of nanometers with a side mode suppression ratio exceeding 35 dB through the adjustment of currents into the phase control sections in the rings. The coupled-ring reflector laser diode has a long effective cavity compared with conventional laser diodes. Accordingly, a broad additional resonance peak in the amplitude modulation characteristics is observed between 20 to 30 GHz, implying the extension of amplitude modulation bandwidth.