Miracle-dz/UniFAR-FTUs huggingface dataset:
Solid-body-type vortex solutions of the Euler equations

A class of unsteady vortex solutions of the Euler equations is investigated. The solutions satisfy the von Kármán–Bödewadt similarity scalings and correspond to free and forced oscillations of radially unbounded solid-body-type vortices with axially varying rotation rates. The vortices may be of unbounded vertical extent or confined by impermeable top and/or bottom plates. In the latter case the bounding plates may be stationary or oscillatory. A solution breakdown result tends to support the hypothesis that breakdown of viscous Bödewadt-type counter-rotating vortex flows is an essentially inviscid process.
Pulse Methylprednisolone Versus Dexamethasone in COVID-19: A Multicenter Cohort Study

IMPORTANCE: Although pulse (high-dose) methylprednisolone therapy can hypothetically control immune system flare-ups effectively, the clinical benefit of pulse methylprednisolone compared with dexamethasone in COVID-19 remains inconclusive. OBJECTIVES: To compare pulse methylprednisolone to dexamethasone as a COVID-19 treatment. DESIGN, SETTING, AND PARTICIPANTS: Using a Japanese multicenter database, we identified adult patients admitted for COVID-19 and discharged between January 2020 and December 2021 treated with pulse methylprednisolone (250, 500, or 1,000 mg/d) or IV dexamethasone (≥ 6 mg/d) at admission day 0 or 1. Main Outcomes and Measures: The primary outcome was in-hospital mortality. Secondary outcomes were 30-day mortality, new ICU admission, insulin initiation, fungal infection, and readmission. Multivariable logistic regression was conducted to differentiate the dose of pulse methylprednisolone (250, 500, or 1,000 mg/d). Additionally, subgroup analyses by characteristics such as the need for invasive mechanical ventilation (IMV) were also conducted. RESULTS: A total of 7,519, 197, 399, and 1,046 patients received dexamethasone, 250, 500, and 1,000 mg/d of methylprednisolone, respectively. The crude in-hospital mortality was 9.3% (702/7,519), 8.6% (17/197), 17.0% (68/399), and 16.2% (169/1,046) for the different doses, respectively. The adjusted odds ratio (95% CI) was 1.26 (0.69–2.29), 1.48 (1.07–2.04), and 1.75 (1.40–2.19) in patients starting 250, 500, and 1,000 mg/d of methylprednisolone, respectively, compared with those starting dexamethasone. In subgroup analyses, the adjusted odds ratio of in-hospital mortality was 0.78 (0.25–2.47), 1.12 (0.55–2.27), and 1.04 (0.68–1.57) in 250, 500, and 1,000 mg/d of methylprednisolone, respectively, among patients with IMV, whereas the adjusted odds ratio was 1.54 (0.77–3.08), 1.62 (1.13–2.34), and 2.14 (1.64–2.80) among patients without IMV. CONCLUSIONS AND RELEVANCE: Higher doses of pulse methylprednisolone (500 or 1,000 mg/d) may be associated with worse COVID-19 outcomes when compared with dexamethasone, especially in patients not on IMV.
Absolutely Continuous Flows Generated by Sobolev Class Vector Fields in Finite and Infinite Dimensions

Abstract We prove the existence of the global flow {Ut} generated by a vector field A from a Sobolev class W1, 1(μ) on a finite- or infinite-dimensional space X with a measure μ, provided μ is sufficiently smooth and that a ∇A and |δμA| (where δμA is the divergence with respect to μ) are exponentially integrable. In addition, the measure μ is shown to be quasi-invariant under {Ut}. In the case X= R n and μ=p dx, where p∈W1, 1loc( R n) is a locally uniformly positive probability density, a sufficient condition is exp(c ‖∇A‖)+exp(c |(A, (∇p/p))|)∈L1(μ) for all c. In the infinite-dimensional case we get analogous results for measures differentiable along sufficiently many directions. Examples of measures which fit our framework, important for applications, are symmetric invariant measures of infinite-dimensional diffusions and Gibbs measures. Typically, in both cases such measures are essentially non-Gaussian. Our result in infinite dimensions significantly extends previously studied cases where μ was a Gaussian measure. Finally, we study flows generated by vector fields whose values are not necessarily in the Cameron–Martin space.
Modelling of an InAs/GaSb/InSb short-period superlattice laser diode for mid-infrared emission by the k.p method

The electronic band structure and optical gain of an InAs/GaSb/InSb short-period superlattice laser diode on a GaSb substrate are numerically investigated with an accurate 8 × 8 k.p model. Using a realistic graded and asymmetric interface profile, we obtain a reasonable agreement on band gap energy with our experimental data extracted from laser emissions performed on the laser diode. The optical performance in terms of optical gain is then calculated for the laser structure and we demonstrate the utility of interface design to model short-period superlattice structures.
Assessing Uncertainty in Support-Adjusted Spatial Misalignment Problems

Existing data from multiple sources (e.g., surveillance systems, health registries, governmental agencies) are the foundation for analysis and inference in many studies and programs. More often than not, these data have been collected on different geographical or spatial units, and each of these may be different from the ones of interest. Numerous statistical issues are associated with combining such disparate data. Florida's efforts to move toward implementation of The Centers for Disease Control and Prevention's (CDC's) Environmental Public Health Tracking (EPHT) Program aptly illustrate these issues, which are typical of almost any study designed to measure the association between environmental hazards and health outcomes. In this article, we consider the inferential issues that arise when a potential explanatory variable is measured on one set of spatial units, but then must be predicted on a different set of spatial units. We compare the results from two different approaches to linking health and environmental data on different spatial units, focusing on the need to account for spatial scale and the support of spatial data in the analysis. We compare methods for assessing uncertainty and the potential bias that arises from using predicted variables in spatial regression models. Our focus is on relatively simple methods and concepts that can be transferred to the states' departments of health, the organizations responsible for implementing EPHT.
Empirical Analysis of Global Markets Herding on COVID-19 Effect

This article investigates the presence of herding on global stock markets during COVID-19. Cross-Sectional Absolute Deviation developed by Chiang and Zheng (2010) and Chang et al. (2000) examine market-wide herding. Results show that herding is prevalent in Brazil, Germany, India, Italy, Korea, China-Shanghai, China-Shenzhen and Turkey. During the epidemic, no evidence of herding was detected in France, Hong Kong, Indonesia, Japan, Malaysia, Poland, the United Kingdom and the United States. It has been shown that the United States and Chinese cross-market herding substantially influences all markets. The impact of analyst information (target price, EPS forecasts and revenue predictions) on herding is shown before the pandemic and weakening during the pandemic. It indicates that investors disregard expert recommendations and liquidate equities during the pandemic. The findings shed light on the occurrence and determinants of herding that causes investors’ to behave irrationally during COVID-19. Policymakers, government and regulators should formulate a more robust policy to monitor, control and oversee the naïve herding that drives fundamentals away from stock prices.
The Theory of Oil-Whip in Journal Bearings

Since the oil-whip was found by Newkirk and Taylor about 30 years ago, the effect of the oil film on this phenomenon has been more precisely studied by many people. It seems to us, however, that no satisfactory explanation for the phenomenon has been yet given, probably because of the inadequate assumptions they have made. In the present paper, the phenomenon is discussed as a problem of the dynamical stability of a rotating shaft with a journal bearing, considering the influences of the shaft motion on the pressure distribution of the bearing, and assuming that the pressure of oil in the unshaded region of Fig. 1 is zero. Then the equation of motion of the shaft is given by (13), and the Routh's criterion gives the stability chart as shown in Fig. 5 for this system, in which the shaded area represents the unstable region and the unshaded area the stable region. The symbols appearing in the stability chart are as follows : γ : radius of bearing b : width of bearing δ : radial clearance between shaft and bearing χ : eccentricity ratio F : transvers load upon the shaft m : (equivalent) mass of the rotor μ : coefficient of viscosity of the lubricant ω : angular velocity of the shaft. This chart shows that the system is always stable (the shaft can be always stably driven), if the deviation of the center of the shaft from that of the bearing is more than 70% of the bearing clearance, or if the vertical displacement of the shaft center from its lowest position is less than 50% of the clearance. This agrees with the practical experiences.
Newly identified cold subdwarfs: LHS 375, LHS 407, LHS 3181, and LHS 3555

Four new cold subdwarfs have been identified from Luyten's LHS Catalogue (1976), LHS 375, LHS 407, LHS 3181, and LHS 3555. CCD B, V, R, and I photometry; infrared J, H, and K photometry and spectra of the stars have been obtained. We discuss their location in different color-color diagrams. They suggest a subdwarf class, and are consistent with the strengths of their CaH bands with respect to TiO bands. We also obtained CCD trigonometric parallaxes indicating absolute visual magnitudes for them from 1.5 to 2 mag below the dwarf main sequence
Multipole solution for the macroscopic electromagnetic boundary conditions at a vacuum—dielectric interface

Multipole solutions are obtained for the boundary conditions on the macroscopic electromagnetic fields at the surface of a semi–infinite homogeneous medium in a vacuum, which may be anisotropic, magnetic and chiral. The theory is based on the differential forms of Maxwell's equations and is developed within the electric octopole–magnetic quadrupole approximation, since optical effects are known which require this multipole order for their description. To ensure that both spatial invariance and reciprocity (time–reversal symmetry) are satisfied, it is necessary to take the constitutive relations for the D and H fields in relativistically covariant form. These forms are derived to the order of electric octopole and magnetic quadrupole. The boundary conditions are shown to reduce to the standard Maxwell forms when the properties of the medium are described within the electric dipole approximation D = ε0E + P and H = μ0−1B. However, when higher multipole contributions are included in the constitutive relations, various components of the electromagnetic fields may be macroscopically discontinuous at the interface due to surface densities of bound current, charge, electric dipole moment, etc. The multipole forms for these discontinuities, which are consistent with the use of relativistically covariant D and H fields, are identified.
Planar Laser-Induced Fluorescence Fuel Imaging During Gas-Turbine Relight

This experimental study investigates the influence of fuel distribution on ignition outcome during high-altitude relight of a gas turbine. Planar laser-induced fluorescence is used to image fuel inside a lean direct-injection combustor under realistic conditions. A novel apparatus is developed to permit planar laser-induced fluorescence imaging, in which large quantities of poorly atomized fuel impinges on the internal surfaces of the combustor. Results reveal high variability in atomization quality. In the absence of flame, small droplets are confined to areas of recirculating flow, whereas large droplets impact on the walls. All fuel is introduced through a pilot air-blast atomizer close to the injector centerline. However, comparatively little fuel is apparent near the igniter tip because the outside swirlers of the fuel injector create a fast-moving stream of fuel-free air that flows directly below the upper combustor wall. The droplet size and fuel concentration in the main recirculation zone do not .
Sperm whales forage year-round in the ross sea region

We investigated the seasonal and spatial occurrence of sperm whale (Physeter macrocephalus) in the Ross Sea region of the Southern Ocean derived from passive acoustic data. Two Autonomous Multichannel Acoustic Recorders (AMARs) moored about 10 m above the seabed were deployed in the austral summer of 2018 and recovered 1 year later. The northern AMAR (A3) was located on the Pacific-Antarctic Ridge at 63.7°S and the southern AMAR (A1) at 73.1°S on the Iselin Bank, part of the continental slope of the Ross Sea. Sperm whale echolocation signals were detected using signal processing scripts and validated by visual inspection of spectrograms. Our results demonstrate that sperm whales are present in the Ross Sea region year-round. At A1, sperm whale vocalisations were detected in every month between February and November, but absent in December and January. Whales were detected most often in February with an average of 0.310 detections per hour. Sperm whale vocalisations were detected at station A3 in every month except February when we had no observations. Our results contrast to a paucity of reported sightings of sperm whales from fishing and research vessels in the Ross Sea region between December and February. Probabilities of detecting sperm whales at A3 were on average 14.2 times higher than at A1 for the same month and monthly mean detections per hour were an average of 74.4 times higher at A3 than A1. At A1, we found a significant preference for day-time foraging rather than during the night or nautical twilight. In contrast, at A3, no clear day/dusk/night/dawn differences in sperm whale occurrence were found. Low sea-ice concentration (< 80%) and open water within ∼50 km were necessary but not sufficient conditions for higher detection rates of sperm whales (>0.1 detections per hour). Overall, our research provides baseline information on sperm whale occurrence and establishes a method to track long-term change to help evaluate the conservation value of the Ross Sea region Marine Protected Area.
Evaluation of outcome of chemotherapy for breast cancer patients older than 70 years: A SEER-based study

Background With the aging of the population, the number of elderly breast cancer cases has increased. However, there is a lack of effective randomized clinical trial data to support whether elderly patients should receive chemotherapy. Our goal was to observe the relationship between chemotherapy and breast cancer-specific survival (BCSS) in elderly breast cancer patients and to identify those who could benefit from chemotherapy. Methods We collected the data of patients who were diagnosed with invasive ductal carcinoma and older than 70 years in the SEER database from 1995 to 2016. The independent predictors of BCSS were identified by Cox regression analysis. Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were performed to eliminate confounding factors. Results A total of 142,537 patients were collected, including 21,782 patients in the chemotherapy group and 120,755 patients in the non-chemotherapy group. We identified the same potential predictors of BCSS after PSM and IPTW, such as age, race, grade, stage, therapy, subtype. A nomogram for predicting 3-year, 5-year and 10-year BCSS was constructed. The 3-year, 5-year and 10-year AUCs of the nomogram were 0.842, 0.819, and 0.788. According to the risk stratification of model predictive scores, patients in the high-risk group achieved the greatest improvement in BCSS after receiving chemotherapy. Conclusions Our study suggests that women older than 70 years with larger tumors, higher grade, positive nodes, negative hormone receptor and inactive local therapy gain prognostic benefits from chemotherapy, but for those with low- and median-risk, conventional chemotherapy should be administered cautiously.
Single-cell RNA sequencing reveals in vivo osteoimmunology interactions between the immune and skeletal systems

Background While osteoimmunology interactions between the immune and skeletal systems are known to play an important role in osteoblast development, differentiation and bone metabolism related disease like osteoporosis, such interactions in either bone microenvironment or peripheral circulation in vivo at the single-cell resolution have not yet been characterized. Methods We explored the osteoimmunology communications between immune cells and osteoblastic lineage cells (OBCs) by performing CellphoneDB and CellChat analyses with single-cell RNA sequencing (scRNA-seq) data from human femoral head. We also explored the osteoimmunology effects of immune cells in peripheral circulation on skeletal phenotypes. We used a scRNA-seq dataset of peripheral blood monocytes (PBMs) to perform deconvolution analysis. Then weighted gene co-expression network analysis (WGCNA) was used to identify monocyte subtype-specific subnetworks. We next used cell-specific network (CSN) and the least absolute shrinkage and selection operator (LASSO) to analyze the correlation of a gene subnetwork identified by WGCNA with bone mineral density (BMD). Results We constructed immune cell and OBC communication networks and further identified L-R genes, such as JAG1 and NOTCH1/2, with ossification related functions. We also found a Mono4 related subnetwork that may relate to BMD variation in both older males and postmenopausal female subjects. Conclusions This is the first study to identify numerous ligand-receptor pairs that likely mediate signals between immune cells and osteoblastic lineage cells. This establishes a foundation to reveal advanced and in-depth osteoimmunology interactions to better understand the relationship between local bone microenvironment and immune cells in peripheral blood and the impact on bone phenotypes.
A tale of two lexica: Investigating computational pressures on word representation with neural networks

Introduction The notion of a single localized store of word representations has become increasingly less plausible as evidence has accumulated for the widely distributed neural representation of wordform grounded in motor, perceptual, and conceptual processes. Here, we attempt to combine machine learning methods and neurobiological frameworks to propose a computational model of brain systems potentially responsible for wordform representation. We tested the hypothesis that the functional specialization of word representation in the brain is driven partly by computational optimization. This hypothesis directly addresses the unique problem of mapping sound and articulation vs. mapping sound and meaning. Results We found that artificial neural networks trained on the mapping between sound and articulation performed poorly in recognizing the mapping between sound and meaning and vice versa. Moreover, a network trained on both tasks simultaneously could not discover the features required for efficient mapping between sound and higher-level cognitive states compared to the other two models. Furthermore, these networks developed internal representations reflecting specialized task-optimized functions without explicit training. Discussion Together, these findings demonstrate that different task-directed representations lead to more focused responses and better performance of a machine or algorithm and, hypothetically, the brain. Thus, we imply that the functional specialization of word representation mirrors a computational optimization strategy given the nature of the tasks that the human brain faces.
A review on experimental surgical models and anesthetic protocols of heart failure in rats

Heart failure (HF) is a serious health and economic burden worldwide, and its prevalence is continuously increasing. Current medications effectively moderate the progression of symptoms, and there is a need for novel preventative and reparative treatments. The development of novel HF treatments requires the testing of potential therapeutic procedures in appropriate animal models of HF. During the past decades, murine models have been extensively used in fundamental and translational research studies to better understand the pathophysiological mechanisms of HF and develop more effective methods to prevent and control congestive HF. Proper surgical approaches and anesthetic protocols are the first steps in creating these models, and each successful approach requires a proper anesthetic protocol that maintains good recovery and high survival rates after surgery. However, each protocol may have shortcomings that limit the study's outcomes. In addition, the ethical regulations of animal welfare in certain countries prohibit the use of specific anesthetic agents, which are widely used to establish animal models. This review summarizes the most common and recent surgical models of HF and the anesthetic protocols used in rat models. We will highlight the surgical approach of each model, the use of anesthesia, and the limitations of the model in the study of the pathophysiology and therapeutic basis of common cardiovascular diseases.
The effect of a startle-based warning, age, sex, and secondary task on takeover actions in critical autonomous driving scenarios

Introduction: In highly autonomous driving scenarios, it is critical to identify strategies to accelerate reaction times since drivers may take too long to take over control of the vehicle. Previous studies reported that an Acoustic Startling Pre-Stimulus (ASPS, i.e., a loud warning preceding an action) accelerated reaction times in simple ankle flexion exercises. Methods: In this study, we examined if an ASPS warning leads to shorter takeover reaction times in a sled-simulated evasive swerving maneuver. Twenty-eight participants (seven male adults, seven male teenagers, seven female adults, and seven female teenagers) were instructed to align a marker on the steering wheel with a marker on a lateral post as fast as they could as soon as the lateral sled perturbation (0.75 g) started. Four conditions were examined: with and without an ASPS (105 dB, played 250 ms before sled perturbation for 40 ms), and with and without a secondary task (i.e., texting). A catch trial (ASPS only) was used to minimize anticipation. Human kinematics were captured with an 8-camera 3D motion capture system. Results: Results showed that the drivers’ hands lifted towards the steering wheel more quickly with the ASPS (169 ± 55 ms) than without (194 ± 46 ms; p = 0.01), and that adult drivers touched the steering wheel quicker with the ASPS (435 ± 54 ms) than without (470 ± 33 ms; p = 0.01). Similar findings were not observed for the teen drivers. Additionally, female drivers were found to lift their hands towards the steering wheel faster than male drivers (166 ± 58 ms vs. 199 ± 36 ms; p = 0.009). Discussion: Our findings suggest that the ASPS may be beneficial to accelerate driver reaction times during the initiation of a correction maneuver, and that autonomous vehicle warnings may need to be tailored to the age and sex of the driver.