Miracle-dz/UniFAR-FTUs huggingface dataset:
Improvements in the M-T relation and mass function and the measured Omega_m through clusters evolution

In this paper, I revisit the constraints obtained by several authors (Reichart et al. 1999; Eke et al. 1998; Henry 2000) on the estimated values of Omega_m, n and sigma_8 in the light of recent theoretical developments: 1) new theoretical mass functions (Sheth & Tormen 1999, Sheth, Mo & Tormen 1999, Del Popolo 2002b); 2) a more accurate mass-temperature relation, also determined for arbitrary Omega_m and Omega_{\Lambda} (Voit 2000, Pierpaoli et al. 2001, Del Popolo 2002a). Firstly, using the quoted improvements, I re-derive an expression for the X-ray Luminosity Function (XLF), similarly to Reichart et al. (1999), and then I get some constraints to \Omega_m and n, by using the ROSAT BCS and EMSS samples and maximum-likelihood analysis. Then I re-derive the X-ray Temperature Function (XTF), similarly to Henry (2000) and Eke et al. (1999), re-obtaining the constraints on Omega_m, n, sigma_8. Both in the case of the XLF and XTF, the changes in the mass function and M-T relation produces an increase in Omega_m of \simeq 20% and similar results in sigma_8 and n.
A black ring with a rotating 2-sphere

We present a solution of the vacuum Einstein’s equations in five dimensions corresponding to a black ring with horizon topology S 1 ×S 2 and rotation in the azimuthal direction of the S 2 . This solution has a regular horizon up to a conical singularity, which can be placed either inside the ring or at infinity. This singularity arises due to the fact that this black ring is not balanced. In the infinite radius limit we correctly reproduce the Kerr black string, and taking another limit we recover the Myers-Perry black hole with a single angular momentum.
Diet and colorectal cancer in UK Biobank: a prospective study

Abstract Background Most of the previous studies on diet and colorectal cancer were based on diets consumed during the 1990s. Methods We used Cox-regression models to estimate adjusted hazard ratios for colorectal cancer by dietary factors in the UK Biobank study. Men and women aged 40–69 years at recruitment (2006–10) reported their diet on a short food-frequency questionnaire (n = 475 581). Dietary intakes were re-measured in a large sub-sample (n = 175 402) who completed an online 24-hour dietary assessment during follow-up. Trends in risk across the baseline categories were calculated by assigning re-measured intakes to allow for measurement error and changes in intake over time. Results During an average of 5.7 years of follow-up, 2609 cases of colorectal cancer occurred. Participants who reported consuming an average of 76 g/day of red and processed meat compared with 21 g/day had a 20% [95% confidence interval (CI): 4–37] higher risk of colorectal cancer. Participants in the highest fifth of intake of fibre from bread and breakfast cereals had a 14% (95% CI: 2–24) lower risk of colorectal cancer. Alcohol was associated with an 8% (95% CI: 4–12) higher risk per 10 g/day higher intake. Fish, poultry, cheese, fruit, vegetables, tea and coffee were not associated with colorectal-cancer risk. Conclusions Consumption of red and processed meat at an average level of 76 g/d that meets the current UK government recommendation (≤90 g/day) was associated with an increased risk of colorectal cancer. Alcohol was also associated with an increased risk of colorectal cancer, whereas fibre from bread and breakfast cereals was associated with a reduced risk.
Tricritical behavior in the extended Hubbard chains

Phase diagrams of the one-dimensional extended Hubbard model (including nearest-neighbor interaction $V$) at half- and quarter-filling are studied by observing level crossings of excitation spectra using the exact diagonalization. This method is based on the Tomonaga-Luttinger liquid theory including logarithmic corrections which stem from the renormalization of the Umklapp- and the backward-scattering effects. Using this approach, the phase boundaries are determined with high accuracy, and then the structure of the phase diagram is clarified. At half-filling, the phase diagram consists of two Berezinskii-Kosterlitz-Thouless (BKT) transition lines and one Gaussian transition line in the charge sector, and one spin-gap transition line. This structure reflects the U(1) $\otimes$ SU(2) symmetry of the electron system. Near the $U=2V$ line, the Gaussian and the spin-gap transitions take place independently from the weak- to the intermediate-coupling region, but these two transition lines are coupled in the strong-coupling region. This result demonstrates existence of a tricritical point and a bond-charge-density-wave (BCDW) phase between charge- and spin-density-wave (CDW, SDW) phases. To clarify this mechanism of the transition, we also investigate effect of a correlated hopping term which plays a role to enlarge BCDW and bond-spin-density-wave (BSDW) phases. At quarter-filling, a similar crossover phenomenon also takes place in the large-$V$ region involving spin-gap and BKT-type metal-insulator transitions.
High-Resolution Observations and Modeling of Dynamic Fibrils

We present unprecedented high-resolution Hα observations, obtained with the Swedish 1 m Solar Telescope, that, for the first time, spatially and temporally resolve dynamic fibrils in active regions on the Sun. These jetlike features are similar to mottles or spicules in quiet Sun. We find that most of these fibrils follow almost perfect parabolic paths in their ascent and descent. We measure the properties of the parabolic paths taken by 257 fibrils and present an overview of the deceleration, maximum velocity, maximum length, and duration, as well as their widths and the thickness of a bright ring that often occurs above dynamic fibrils. We find that the observed deceleration of the projected path is typically only a fraction of solar gravity and incompatible with a ballistic path at solar gravity. We report on significant differences of fibril properties between those occurring above a dense plage region and those above a less dense plage region where the magnetic field seems more inclined from the vertical. We compare these findings to advanced numerical two-dimensional radiative MHD simulations and find that fibrils are most likely formed by chromospheric shock waves that occur when convective flows and global oscillations leak into the chromosphere along the field lines of magnetic flux concentrations. Detailed comparison of observed and simulated fibril properties shows striking similarities of the values for deceleration, maximum velocity, maximum length, and duration. We compare our results with observations of mottles and find that a similar mechanism is most likely at work in the quiet Sun.
Growth and optical properties of GaN/AlN quantum wells

We demonstrate the growth of GaN/AlN quantum-well structures by plasma-assisted molecular-beam epitaxy by taking advantage of the surfactant effect of Ga. The GaN/AlN quantum wells show photoluminescence emission with photon energies in the range between 4.2 and 2.3 eV for well widths between 0.7 and 2.6 nm, respectively. An internal electric field strength of 9.2±1.0 MV/cm is deduced from the dependence of the emission energy on the well width.
New fast models of the Galactic tide

New models of the action of the Galactic tide on the motion of the Oort Cloud comets are investigated. The first one consists of the Hamiltonian form of the equations of motion which are averaged over the mean anomaly including the radial component of the tide. The second is a series of mappings which allows a noticeable reduction of the computer time. These models are checked in three different frames, and some of them turn out to be reliable for a wide range of initial conditions. In the last experiment we simulate the transport of 10 5 Oort Cloud comets to the inner Solar system under the Galactic tide impulse alone. For such a simulation, the best compromise between reliability and computer time is given by a mapping of order 3 which is more than 500 times faster than the usual numerical integrations and may be safely used when the comet semimajor axes a < 30 000 au. The present study highlights the qualitative effects of the radial component of the Galactic tide. The models built here will be used in a forthcoming paper for a more realistic study of the transport of long-period comets including planetary perturbations.
Coordinating Numeric and Linear Units: Elementary Students’ Strategies for Locating Whole Numbers on the Number Line

Two investigations of fifth graders’ strategies for locating whole numbers on number lines revealed patterns in students’ coordination of numeric and linear units. In Study 1, we investigated the effects of context on students’ placements of three numbers on an open number line. For one group (n = 24), the line was presented in a thematic context as a “race course,” and, for a second group (n = 24), the line was presented as a conventional number line. Most students in both groups placed consecutive whole numbers at appropriate linear distances, but the thematic context group was more likely to place nonconsecutive whole numbers at appropriate linear distances. In Study 2 (n = 24), students placed numbers on lines marked with two numbers. Most students placed a third number appropriately when the marked numbers were consecutive whole numbers, but not when the labeled numbers were nonconsecutive whole numbers. The findings reveal fifth graders’ conceptual difficulties in coordinating numeric and linear units on the number line and a thematic context that can support this coordination.
Photon polarization and Wigner's little group

To discuss one-photon polarization states we find the explicit form of the Wigner's little group element in the massless case for arbitrary Lorentz transformation. As is well known, when analyzing the transformation properties of the physical states, only the value of the phase factor is relevant. We show that this phase factor depends only on the direction of the momentum k/|k| and does not depend on the frequency k{sup 0}. Finally, we use this observation to discuss the transformation properties of the linearly polarized photons and the corresponding reduced density matrix. We find that they transform properly under Lorentz group.
A three-dimensional sharp interface model for self-consistent keyhole and weld pool dynamics in deep penetration laser welding

A three-dimensional sharp interface model is proposed to investigate the self-consistent keyhole and weld pool dynamics in deep penetration laser welding. The coupling of three-dimensional heat transfer, fluid flow and keyhole free surface evolutions in the welding process is simulated. It is theoretically confirmed that under certain low heat input welding conditions deep penetration laser welding with a collapsing free keyhole could be obtained and the flow directions near the keyhole wall are upwards and approximately parallel to the keyhole wall. However, significantly different weld pool dynamics in a welding process with an unstable keyhole are numerically found. Many flow patterns in the welding process with an unstable keyhole, verified by x-ray transmission experiments, were successfully simulated and analysed. Periodical keyhole collapsing and bubble formation processes are also successfully simulated and believed to be in good agreement with experiments. The mechanisms of keyhole instability are found to be closely associated with the behaviour of humps on the keyhole wall, and it is found that the welding speed and surface tension are closely related to the formation of humps on the keyhole wall. It is also shown that the weld pool dynamics in laser welding with an unstable keyhole are closely associated with the transient keyhole instability and therefore modelling keyhole and weld pool in a self-consistent way is significant to understand the physics of laser welding.
A Technique for Maximizing Details in Numerical Weather Map Analysis

Abstract This paper summarizes the development of a convergent weighted-averaging interpolation scheme which can be used to obtain any desired amount of detail in the analysis of a set of randomly spaced data. The scheme is based on the supposition that the two-dimensional distribution of an atmospheric variable can be represented by the summation of an infinite number of independent waves, i.e., a Fourier integral representation. The practical limitations of the scheme are that the data distribution be reasonably uniform and that the data be accurate. However, the effect of inaccuracies can be controlled by stopping the convergence scheme before the data errors are greatly amplified. The scheme has been tested in the analysis of 500-mb height data over the United States producing a result with details comparable to those obtainable by careful manual analysis. A test analysis of sea level pressure based on the data obtained at only the upper air network stations produced results with essentially the same .
The Improved AMSU Rain-Rate Algorithm and Its Evaluation for a Cool Season Event in the Western United States

Abstract Rain-rate retrievals from passive microwave sensors are useful for a number of applications related to weather forecasting. For example, in the United States, such estimates are useful for offshore rainfall systems approaching land and in regions where the Weather Surveillance Radar-1988 Doppler (WSR-88D) network is inadequate. Improvements have been made to the rain-rate retrieval from the Advanced Microwave Sounding Unit (AMSU) on board the National Oceanic and Atmospheric Administration (NOAA) Polar Orbiting Environmental Satellites (POESs). The new features of the improved rain-rate algorithm include a two-stream correction of the satellite brightness temperatures at 89 and 150 GHz, cloud- and rain-type classification for better retrieval of rain rate, and removal of the two ad hoc thresholds in the ice water path (IWP) and effective diameter (De) retrieval where the scattering signals are very small. In this paper, the new algorithm has been compared to the previous NOAA operational algorith.
Angular Expansion Measurement with the VLA: The Distance to NGC 7027

On propose une nouvelle methode faisant usage du VLA pour mesurer de petites modifications dans la structure des radiosources brillantes. On l'applique a titre d'exemple a la mesure de l'expansion angulaire de NGC 7027 sur une periode de 2,8 ans. On en deduit une distance de 940±200 pc pour la nebuleuse
Geometrical characteristics of desert dust layers over Thessaloniki estimated with backscatter/Raman lidar and the BSC/DREAM model

In this study, we present a multiyear study of Saharan dust intrusions over Thessaloniki, Greece. Observations were performed at Thessaloniki with a combined Raman/elastic lidar system from January 2001 to December 2006 in the framework of European Aerosol Research Lidar Network (EARLINET). During this period we collected a dataset of 33 Raman/lidar observations when Saharan dust was present in the free troposphere over Thessaloniki. To identify the origin of the observed aerosol layer we used 4-day backward trajectories using the National Oceanic and Atmospheric Administration (NOAA) Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model at several altitudes. First, we identify the base and the top of the desert dust layers from the lidar measurements. As long as the boundaries of the dust layers are identified, we calculate the mean optical properties and vertically integrated optical properties within the layers. In the second part of the study, an attempt to validate Dust Regional Atmospheric Modelling (DREAM) simulations is made in terms of aerosol extinction profiles. The median of the base of the dust layers over Thessaloniki as determined by the lidar measurements was found around 2 km, whereas the median of the geometrical centre of the dust layers was found around 3.5 km. Comparisons of modelled and measured aerosol extinction coefficients show that the average geometrical characteristics of the Saharan dust layers are well captured by the model simulations.
Tropopausal Mountain Waves over Arecibo: A Case Study

Abstract Vertically variable horizontal winds observd over Arecibo by to and Woodman, which were previously interpreted as a manifestation of inertia-gravity waves having intrinsic periods comparable to the local inertial period, are reinterpreted as quasi-stationary gravity waves of much shqrter intrinsic period, induced orographically by airflow over the island and mountains of Puerto Rico. The ellipticity of the Viated halograph is attributed to an effect of background wind shears in the presence of such waves. This new interpretation carries implicationsboth for the study of similar wind patterns elsewhere and for the reproducibility ofwind fields at Arecibo, where a natural laboratory for the study of mountain waves, of critical-layer interactions and of associated turbulence appears to be available.
The ν-process with Fully Time-dependent Supernova Neutrino Emission Spectra

The neutrino process that occurs in the outer stellar shells during a supernova explosion and involves neutrino–nucleus reactions produces a range of rare, stable, and radioactive isotopes. We improve previous ν-process studies by using, for the first time, the time-dependent neutrino emission spectra, as predicted from supernova simulations, rather than a simplified parametric description modeled after the neutron star cooling phase. In particular, our calculations use time-dependent neutrino spectra for all neutrino species, consider their deviation from a Fermi–Dirac distribution, and account for the neutrino emission from the neutrino burst and accretion phases. We find that the time-dependent treatment of the neutrino emission spectra results in higher yields for the selected nuclei produced by the ν process as compared to previous studies and to the approximation of assuming constant neutrino energies corresponding to the time-averaged mean energy radiated in each species. The effect is largest for nuclides produced by charged-current reactions. Our results reflect the dynamical competition between neutrino-induced reactions and the effect of the shock passage through the star. By varying the neutrino burst luminosity and the duration of the accretion phase, we study the impact of these early emission phases and their uncertainties on the ν-process nucleosynthesis. We find that the deviation of the neutrino spectra from a Fermi–Dirac distribution calculated in supernova simulations has a negligible effect on the ν-process yields.
The Role of Uric Acid in Acute Kidney Injury

Studies have demonstrated the presence of a strong association between serum uric acid (SUA) and acute kidney injury (AKI) consistently across several disease models. Exposure to SUA at different time periods and concentrations has reliably resulted in AKI whether assessed by conventional or novel biomarkers or by kinetic estimated glomerular filtration rate (KeGFR) engineered for non-steady dynamic states. In experimental models, moderate hyperuricemia was associated with an absence of intrarenal crystals, manifestation of tubular injury, macrophage infiltration, and increased expression of inflammatory mediators that were attenuated with uric acid lowering therapy with rasburicase, a recombinant urate oxidase. In a pilot clinical trial, treatment with rasburicase was associated with a decreased incidence of AKI and evidence for less renal structural injury. Lowering SUA also improved KeGFR and estimated glomerular filtration rate in 2 separate studies. SUA has also been linked to diabetic nephropathy, hypertension, cardiovascular disease, chronic kidney disease, metabolic syndrome, and their mechanisms of action share many common traits. In this article, we explore the evidence for the causal role of SUA in AKI using Bradford Hill criteria as a guideline with data integration from related fields.
A neutral hydrogen survey of polar ring galaxies - IV. Parkes observations

A total of 33 polar ring galaxies and polar ring galaxy candidates were observed in the 21-cm H i line with the 64-m Parkes radio telescope. The objects, selected by their optical morphology, are all south of declination {39 and in only 5o f them Hi had been reported previously. H i line emission was detected towards 18 objects, though in 3 cases the detection may be confused by another galaxy in the telescope beam, and one is a marginal detection. Eight objects were detected for the rst time in Hi ,o f which 5d id not have previously known redshifts.
Bell’s theorem: Does quantum mechanics contradict relativity?

Special relativity demands a locality principle (no instantaneous action at a distance); locality implies Bell’s theorem; quantum mechanics violates Bell’s inequality, therefore, quantum mechanics contradicts relativity! Or so it would seem. It is shown, however, that the locality principle needed for Bell’s theorem is stronger than the simple locality that is needed to satisfy the demands of relativity and that quantum mechanics satisfies the latter. The stronger locality principle is equivalent to the conjunction of simple locality and predictive completeness, and it is the latter principle that fails. The notion of predictive completeness is weaker than, and is implied by, the completeness criterion of Einstein, Podolsky, and Rosen. But the quantum mechanical state description is not only incomplete but incompletable, for any local complete state description would satisfy Bell’s inequality and disagree with experiment.
Evolution of localized disturbances in the elliptic instability

Abstract The time evolution of localized disturbances in an elliptical flow confined in an elliptical cylinder is studied by direct numerical simulation (DNS). The base flow is subject to the elliptic instability. The unstable growth of localized disturbances predicted by the short-wavelength stability analysis is captured. The time evolution can be divided into four stages: linear, weakly nonlinear, nonlinear and turbulent. In the linear stage a single wavepacket grows exponentially without changing its shape. The exponential growth is accompanied by large oscillations which have time period half that of the fluid particles in the elliptical flow. An averaged wavepacket, which is a train of bending waves that has a finite spatial extent, also grows exponentially, while the oscillations of the growth rate are small. The averaged growth rate increases as the kinematic viscosity decreases; the inviscid limit is close to the value predicted by the short-wavelength stability analysis. In the weakly nonlinear stage the energy stops growing. The vortical structure of the initial disturbances is deformed into wavy patterns. The energy spectrum loses the peak at the initial wavenumber, developing a broad spectrum, and the flow goes into the next stage. In the nonlinear stage weak vorticity is scattered in the whole domain although strong vorticity is still localized. The probability density functions (p.d.f.) of a velocity component and its longitudinal derivative are similar to those of isotropic turbulence; however, the energy spectrum does not have an inertial range showing the Kolmogorov spectrum. Finally in the turbulent stage fine-scale structures appear in the vorticity field. The p.d. f. of the longitudinal derivative of velocity shows the strong intermittency known for isotropic turbulence. The energy spectrum attains an inertial range showing the Kolmogorov spectrum. The turbulence is not symmetric because of rotation and strain; the component of vorticity in the compressing direction is smaller than the other two components. The energy of the mean flow as well as the total energy decreases. The ratio of the lost energy to the initial energy of the mean flow is large in the core region.