Miracle-dz/UniFAR-FTUs huggingface dataset:
The primordial abundance of 4He from a large sample of low-metallicity H ii regions

Abstract We determine the primordial helium mass fraction Yp using 1700 spectra of low-metallicity extragalactic H ii regions. This sample is selected from the Data Release 7 of the Sloan Digital Sky Survey, from European Southern Observatory archival data and from our own observations. We have considered known systematic effects which may affect the 4He abundance determination. They include collisional and fluorescent enhancements of He i recombination lines, underlying He i and hydrogen stellar absorption lines, collisional excitation of hydrogen lines, temperature and ionization structure of the H ii region. Monte Carlo methods are used to solve simultaneously the above systematic effects. We find a primordial helium mass fraction Yp = 0.2512 ± 0.0006(stat.) ± 0.0020 (syst.). This value is higher than the value given by Standard Big Bang Nucleosynthesis (SBBN) theory. If confirmed, it would imply slight deviations from SBBN.
Vortex dynamics in a spatially accelerating shear layer

An experimental and analytical study into the vortex dynamics of a stratified shear layer subjected to a spatial acceleration is presented. The outer flow is dictated by a hydraulically controlled wedge flow which provides a spatially accelerating shear layer and baroclinic generation of vorticity along the inclined interface. A new, finite-amplitude mechanism is observed in which the core of the growing vortex is separated from the vorticity source at the interface. A secondary core develops and an altered vortex pairing interaction is observed. A spatial linear stability analysis reveals that one of two modified Kelvin–Helmholtz modes is dominant, resulting in the centre of the instability being offset from the density interface into the slower moving stream. Digital particle imaging velocimetry (DPIV) measurements are presented along with flow visualization which indicate that the mechanism is a result of the offset in the vortex core from the source of vorticity at the interface combined with the effects of spatial acceleration and buoyancy. The mixing induced by the interfacial instabilities is such that a sharp density interface remains near the high-momentum stream, with a low-gradient region extending into the low-momentum stream.
Is human immunodeficiency virus a risk factor for the development of nonunion?—a case–control study

Abstract Objective: Human immunodeficiency virus (HIV) infection has been suggested to be associated with an increased risk of the development of nonunion after a fracture. This prospective matched case–control study in South Africa investigated common risk factors, including HIV status, that influence the development of a nonunion after a femur or tibia fracture. Methods: Adult participants (cases) with established nonunions of the femur or tibia shaft were recruited over a 16-month period, between December 2017 and April 2019. They were matched for (1) age; (2) sex; (3) fracture site; and (4) fracture management type, with “control” participants who progressed to fracture union within 6 months of injury. All participants were tested for HIV. Multivariable logistic regression models were constructed to investigate associations between known risk factors for the development of nonunion and impaired fracture healing. Results: A total of 57 cases were matched with 57 “control” participants (44/57 male, 77.2% vs. 13/57 female, 22.8%, median age 36 years). HIV status was not associated with the development of nonunion after the management of tibia and femur fractures, on both univariate (odds ratio, 0.40; confidence interval, 0.10–1.32; P = 0.151) or multivariable (odds ratio, 0.86; confidence interval, 0.18–3.73; P = 0.831) analysis. No other confounding factors were shown to have any statistically significant impact on the odds of developing nonunion in this study cohort. Conclusion: This study demonstrates that HIV does not seem to increase the risk of the development of nonunion and HIV-positive individuals who sustain a fracture can be managed in the same manner as those who are HIV negative.
A representation for algebraic K-theory of quasi-coherent modules over affine spectral schemes

In this paper, we study K-theory of spectral schemes by using locally free sheaves. Let us regard the K-theory as a functor K on affine spectral schemes. Then, we prove that the group completion $\Omega B^{\mathcal{G}}(B^{\mathcal{G}}GL)$ represents the sheafification of K with respect to Zariski (resp. Nisnevich) topology $\mathcal{G}$, where $B^{\mathcal{G}}GL$ is a classifying space of a colimit of affine spectral schemes $GL_n$.
Nonlinear optical microscopy and microspectroscopy of oral precancers and early cancer

Multiphoton autofluorescence microscopy (MPAM) offers the ability to assess morphometry similar to that of pathologic evaluation as well as biochemical information from endogenous fluorophores which are altered with neoplastic transformation. In this study the spectroscopic properties of normal and neoplastic oral epithelium were evaluated toward the goal of identifying image/spectroscopic based indicators of neoplastic transformation using nonlinear optical microscopy. Results indicated measureable differences between normal, dysplasia, and SCC that could be helpful in delineating between the three conditions. In particular, a blue shift in autofluorescence emission was experienced for dysplasia relative to normal. However, in the case of SCC the epithelial emission experienced a significant red shift relative to both dysplasia and normal and displayed in an additional red peak that was not present in either normal or dysplastic mucosa. Results were consistent with published results for SCC in the single-photon literature. The study demonstrates that multiphoton autofluorescence spectroscopy may reveal features of oral mucosa that can be useful for differentiating normal and neoplastic mucosa. When combined with morphometry provided by MPAM, a potentially powerful technique for imaging of the oral cavity could be developed which provides both morphometric and spectroscopic information.
Generation and breakup of Worthington jets after cavity collapse. Part 2. Tip breakup of stretched jets

The capillary breakup of the high-speed Worthington jets ejected after a cavity collapse in water occurs due to the high-Reynolds-number version of the capillary end-pinching mechanism first described, in the creeping flow limit, by Stone & Leal (J. Fluid Mech., vol. 198, 1989, p. 399). Using potential flow numerical simulations and theory, we find that the resulting drop ejection process does not depend on external noise and can be described as a function of a single dimensionless parameter, WeS = ρ R30S20/σ, which expresses the ratio of the capillary time to the inverse of the local strain rate, S0. Here, ρ and σ indicate the liquid density and the interfacial tension coefficient, respectively, and R0 is the initial radius of the jet. Our physical arguments predict the dimensionless size of the drops to scale as Ddrop/R0 ~ We−1/7S and the dimensionless time to break up as TS0 ~ We2/7S. These theoretical predictions are in good agreement with the numerical results.
High-resolution bootstrapped differential semblance

ABSTRACTWe formulated two coherency measures, based on the bootstrapped differential semblance (BDS) estimator, that offered higher resolution in parameter tracking than did standard normalized differential semblance. Bootstrapping is a statistical resampling procedure used to infer estimates of standard errors and confidence intervals from data samples for which the statistical properties are unattainable via simple means, or when the probability density function is unkown or difficult to estimate. The first proposed estimator was based on a deterministic sorting of original offset traces by alternating near and far offsets to achieve maximized time shifts between adjacent traces. The near offsets were indexed with odd integers, while the even integers were used to index far offsets that were located at a constant index increment from the previous trace. The second was the product of several BDS terms, with the first term being the deterministic BDS defined above. The other terms were generated by random.
Dayside and nightside contributions to the cross polar cap potential: placing an upper limit on a viscous-like interaction

Abstract. Observations of changes in size of the ionospheric polar cap allow the dayside and nightside reconnection rates to be quantified. From these it is straightforward to estimate the rate of antisunward transport of magnetic flux across the polar regions, quantified by the cross polar cap potential Φ PC . When correlated with upstream measurements of the north-south component of the IMF, Φ PC is found to increase for more negative B z , as expected. However, we also find that Φ PC does not, on average, decrease to zero, even for strongly northward IMF. In the past this has been interpreted as evidence for a viscous interaction between the magnetosheath flow and the outer boundaries of the magnetosphere. In contrast, we show that this is the consequence of flows excited by tail reconnection, which is inherently uncorrelated with IMF B z .
A transparent quartz laparoscopic jaw design for infrared laser sealing of vascular tissues using a reciprocating, side-firing fiber

Infrared (IR) lasers are being tested as an alternative to conventional radiofrequency and ultrasonic surgical devices for rapid hemostatic sealing of vascular tissues. During previous studies, a reciprocating, side-firing optical fiber delivered a linear laser beam across compressed vessels, simulating pressure from laparoscopic device jaws. However, technical challenges include limited field-of-view of vessel position within the jaws, and matching the fiber scan length to variable vessel diameters (2-7 mm). Use of transparent laparoscopic jaws may improve the surgeon’s visibility and enable customized treatment. Transparent quartz square tubing (with dimensions of 2.7 x 2.7 x 25 mm, compatible with a standard 5-mm-outer-diameter laparoscopic port) was sealed on its distal end with a black resin plug for absorbing residual forward directed light. Optical transmission studies were conducted using an infrared (IR) diode laser (1470 nm / 30 W). Razor blade scans and an IR beam profiler were used to acquire side-firing fiber (550-um-core / 0.22 NA) spatial beam profiles. Thermocouples (TC) and a thermal camera recorded peak temperatures and cooling times on the inside and outside surfaces of the quartz jaw, respectively. Side-firing fibers polished at a 50° angle delivered 94% of the light radially (90°) and 2.3% in the forward (0°) direction at powers ≤ 34 W. Total reflection losses for the two quartz-air interfaces measured 6% with 94% of side-firing light transmitted through the quartz tubing wall. Peak TC temperatures on the external surface of the jaw measured 85 ± 14 °C with 23 ± 8 s to cool to body temperature (37 °C). Optical and thermal measurements were conducted on a transparent laparoscopic device jaw for IR laser sealing of vascular tissues. Further development and improved visibility may enable customization of fiber scan length to match variable compressed vessel widths during placement within device jaws.
Dynamical evidence for nonlinear Langmuir wave processes in type III solar radio bursts

The nonlinear processes and evolution of Langmuir waves in the source regions of type III solar radio bursts are explored in detail. Langmuir waves recorded by the Time Domain Sampler of the STEREO/WAVES instrument can be roughly classified into six groups based on the waveform, power spectra, and field strength perpendicular to the local magnetic field. It is argued that these groups correspond to either different stages of the evolution of Langmuir waves generated by electron beams or differ due to the direction of the magnetic field relative to the solar wind velocity. Approximately half of the observed Langmuir waves have strong perpendicular fields, meaning that understanding how these fields are produced is crucial for understanding type III sources. Most events recorded are either localized waveforms consistent with Langmuir eigenmodes or have two or more spectral peaks consistent with electrostatic (ES) decay of Langmuir/z mode waves. The remaining events appear to correspond to either earlier or later stages of Langmuir wave evolution or are decay events for which the Doppler shift is insufficient to distinguish the beam‐driven and product Langmuir waves. This is supported by the fact that most events exceed the threshold for ES decay even though their spectra show no evidence for decay and some of the events are observed when the solar wind flow is approximately perpendicular to the magnetic field, minimizing Doppler shifting. Low‐frequency fields produced by intense Langmuir waves are quantitatively consistent with density perturbations produced by the ponderomotive force, ion‐acoustic waves produced by ES decay, or sheath rectification. Above the observed nonlinear threshold, quantitative analysis suggests that the observed low‐frequency signals are consistent with perturbations produced by ponderomotive effects and ion‐acoustic waves produced by ES decay, but effects of sheath rectification may also contribute.
Climate change impacts on native cutthroat trout habitat in Colorado streams

Headwater streams support vital aquatic habitat yet are vulnerable to changing climate due to their high elevation and small size. Coldwater fish are especially sensitive to the altered streamflow and water temperature regimes during summer low flow periods. Though previous studies have provided insights on how changes in climate and alterations in stream discharge may affect habitat availability for various native cutthroat trout species, suitable physical habitats have not been evaluated under future climate projections for the threatened Greenback Cutthroat Trout (GBCT) native to headwater regions of Colorado, USA. Thus, this study used field data collected from selected headwater streams across the current distribution of GBCT to construct one‐dimensional hydraulic models to evaluate streamflow and physical habitat under four future climate projections. Results illustrate reductions in both predicted streamflow and physical habitat for all future climate projections across study sites. The projected mean summer streamflow shows greater decline (−52% on average) compared to the projected decline in mean August flow (−21% on average). Moreover, sites located at a relative higher elevation with larger substrate and steeper slope were projected to experience more reductions in physical habitat due to streamflow reductions. Specifically, streams with step‐pool morphologies may experience grater changes in available habitat compared to pool‐riffle streams. Future climate change studies related to coldwater fish that examine spatial variation in flow alteration could provide novel data to complement the existing literature on the thermal characteristics. Tailoring reintroduction and management efforts for GBCT to the individual headwater stream with adequate on‐site monitoring could provide a more holistic conservation approach.
Dynamic changes in marker components during the stir-frying of Pharbitidis Semen, and network analysis of its potential effects on nephritis

Introduction: Pharbitidis Semen (PS) has been widely used in traditional Chinese medicine to treat several diseases such as nephritis. PS is usually stir-fried to enhance its therapeutic efficacy before use in clinical practice. However, the changes in phenolic acids during stir-frying and the mechanisms of their therapeutic effects on nephritis are still unclear. Methods: Here, we studied the processing-induced chemical changes and elucidated the mechanism of PS in the treatment of nephritis. We determined the levels of the 7 phenolic acids in raw PS (RPS) and stir-fried PS (SPS) using high-performance liquid chromatography, analyzed the dynamic compositional changes during stir-frying, and used network analysis and molecular docking to predict and verify compound targets and pathways corresponding to nephritis. Results: The dynamic changes in the 7 phenolic acids in PS during stir-frying are suggestive of a transesterification reaction. Pathway analysis revealed that the targets of nephritis were mainly enriched in the AGE-RAGE, hypoxia-inducible factor-1, interleukin-17, and tumor necrosis factor signaling pathways among others. Molecular docking results showed that the 7 phenolic acids had good binding ability with the key nephritic targets. Discussion: The potential pharmaceutical basis, targets, and mechanisms of PS in treating nephritis were explored. Our findings provide a scientific basis for the clinical use of PS in treating nephritis.
Characterizations of linear differential systems with a regular singular point

The linear differential system where w is a vector with n components and A is an n by n matrix is said to have z = 0 as a regular singular point if there exists a fundamental matrix of the form such that S is holomorphic at z = 0 and R is a constant matrix ((1), p. 111; (2), p. 73). For such systems A will have at most a pole at z = 0 and we may write where p is an integer, Ã is holomorphic at z = 0, and Ã(0) ≠ 0. However, the converse is not true. When p ≦ − 1, A is holomorphic at z = 0, and every fundamental matrix is holomorphic at z = 0. If p ≧ 1, the non-negative integer p is called (after Poincaré) the rank of the singularity and there is a significant difference between the cases p = 0 and p ≧ 1. If p = 0 the linear differential system (1) is known to have z = 0 as a regular singular point ((1), p. 111) ; whereas, if p ≧ 1, z = 0 may or may not be a regular singular point.
Malnutrition and Insulin Resistance May Interact with Metabolic Syndrome in Prevalent Hemodialysis Patients

Background: We sought to determine the prevalence of metabolic syndrome (Mets) and whether 100 cm2 of visceral fatty area (VFA) measured by computed tomography (CT) validates the criteria of waist circumference (WC) in hemodialysis (HD) patients. Methods: The study comprised 141 HD patients. Mets was defined according to the criteria of Adult Treatment Panel III (ATP III) and the modified criteria of National Cholesterol Education Program (NCEP) that defines abdominal obesity as a WC of >=85 cm in men and >=90 cm in women. Results: The prevalence of Mets was 31.9% in men and 13.6% in women. However, the prevalence of patients with a body mass index over 25 in all HD patients was only 11.2%. The visceral fatty area (VFA) measured by CT showed a strong positive correlation with WC. The patients with Mets, comparing with those without Mets, have significantly shorter duration of HD, higher high-sensitive C-reactive protein, and higher Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). In the patients with Mets, there was a significant negative correlation between HOMA-IR and serum albumin levels. Multivariate logistic regression analysis showed that HOMA-IR and short duration of HD were chosen as independent risk factors for Mets. Conclusions: Mets is more prevalent in HD patients. In Japanese HD patients, 100 cm2 of VFA corresponded to a WC of 85 cm in men and 90 cm in women, thus confirming the validity of the modified criteria. HOMA-IR and serum albumin were significantly correlated in HD patients with Mets.
Lattice-valued Borel measures. II

Let X be a completely regular T1 space, E a boundedly complete vector lattice, C(X) (Cb(X)) the space of all (all, bounded), real-valued continuous functions on X. In order convergence, we consider E-valued, order-bounded, -additive, -additive, and tight measures on X and prove some order-theoretic and topological properties of these measures. Also for an order-bounded, E-valued (for some special E) linear map on C(X), a measure representation result is proved. In case E n separates the points of E, an Alexanderov's type theorem is proved for a sequence of -additive measures.
The time-dependent behaviour of a spinning disc on a rotating planet: A model for geophysical vortex motion

Abstract A recent theory of Nycander (1996) establishing the analogy between the steady westward drift of geophysical vortices and the precession of a rigid-body (in particular a disc spinning about its symmetry axis) is rederived within a Lagrangian framework. This formulation allows the time-dependent properties (e.g., trajectory, spin etc.) of the rigidbody, represented by three coupled ODEs, to be studied. Numerical results for a variety of initial zonal velocities and latitudes are presented. Typically the trajectory consists of a mean westward precession coupled with periodic behaviour which, in the terminology of rigid-body dynamics, is known as nutation. In the limit that β-plane physics are appropriate, it is shown that the nutation is exactly analogous to harmonic inertial oscillations at the local Coriolis frequency.
New light on stellar abundance analyses: Departures from LTE and homogeneity.

▪ Abstract The information on the chemical compositions of stars encoded in their spectra plays a central role in contemporary astrophysics. Stellar element abundances are, however, not observed: to decipher the spectral fingerprints in terms of abundances requires realistic models for the stellar atmospheres and the line-formation processes. Still today, the vast majority of abundance analyses of late-type stars rely on one-dimensional (1D), hydrostatic model atmospheres and the assumption of local thermodynamic equilibrium (LTE). In this review possible systematic errors in studies of F-, G- and K-type stars introduced by these questionable approximations are discussed. Departures from LTE are commonplace and often quite severe, in particular for low surface gravities or metallicities, with minority species and low-excitation transitions being the most vulnerable. Recently, time-dependent, 3D, hydrodynamical model atmospheres have started to be employed for stellar abundance purposes, with large differe.
Contribution of Blood Vessel Activation, Remodeling and Barrier Function to Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBDs) consist of a group of chronic inflammatory disorders with a complex etiology, which represent a clinical challenge due to their often therapy-refractory nature. In IBD, inflammation of the intestinal mucosa is characterized by strong and sustained leukocyte infiltration, resulting in the loss of epithelial barrier function and subsequent tissue destruction. This is accompanied by the activation and the massive remodeling of mucosal micro-vessels. The role of the gut vasculature in the induction and perpetuation of mucosal inflammation is receiving increasing recognition. While the vascular barrier is considered to offer protection against bacterial translocation and sepsis after the breakdown of the epithelial barrier, endothelium activation and angiogenesis are thought to promote inflammation. The present review examines the respective pathological contributions of the different phenotypical changes observed in the microvascular endothelium during IBD, and provides an overview of potential vessel-specific targeted therapy options for the treatment of IBD.