Miracle-dz/UniFAR-FTUs huggingface dataset:
Measurement and analysis of maxillary anterior teeth color in the chinese population

Background To measure the difference in the crown color of the maxillary anterior teeth in the Chinese population, to study its potential regularity, and to provide a reference for the colorimetry of oral anterior teeth restoration. Material and Methods Using VITA Easyshade Advance4.0 spectrophotometer (the colorimetric system is CIE-1976-L*a*b*), adult patients who were treated in Sanming Integrated Medicine Hospital, Fujian Province, China, from January 2022 to June 2022 160 patients (88 males, 72 females, aged 20-60 years) were used as the survey subjects, and the L*a*b* of 1/3 of the crowns of 6 anterior teeth (central incisors, lateral incisors, canines) were measured Value, statistical analysis was performed with SPSS 26.0 software. Results The mean L* values of maxillary central incisors, lateral incisors, and canines in the Chinese population were: (73.02±4.41), (69.96±4.70), (65.14±4.21); the mean a* values were: (-0.54±4.21) 0.35), (0.22±0.63), (1.40±0.62), and the mean values of b* were: (14.50±3.23), (18.60±3.94), (23.64±3.30). 1. There was no significant difference in L*a*b* value between left and right symmetrical teeth with the same name (P>0.05). 2. There was no statistical difference in the L*a*b* value between genders (P>0.05), 3. There was a statistical difference in L*a*b* value between different tooth positions (P< 0.05). 4. There were significant differences in L*a*b* values in different age groups (P< 0.05). Conclusions 1. The color of the labial crown of maxillary anterior teeth in the Chinese population is related to different age groups and tooth positions but not gender. 2. In the Chinese population, the color of the maxillary anterior teeth on the labial side gradually decreased from the central incisor to the distal end of the dental arch while the chroma gradually increased. 3. With age increase, the L* and a* values of the upper central incisors, upper lateral incisors, and upper canines gradually decrease, and the b* value gradually increases. The teeth became darker, more yellow, and redder. 4. In the clinical colorimetry of the upper anterior teeth, the contralateral tooth with the same name is preferred. Suppose the tooth with the same name is missing at the same time. In that case, when using the adjacent teeth as a reference, the different brightness and chroma between the central incisors, lateral incisors, and canine teeth should be compared. Change trend to determine. 5. A uniform tooth color should not be selected for anterior restoration, and age should be considered when choosing a color for the patient. Key words:Upper anterior teeth, Crown color, CIE-1976-L*a*b*, spectrophotometric colorimeter.
Identifying Factors Related to Crash Injury Levels Involving Bicyclists at Different Locations Through Crash Data Analysis

The safety of vulnerable road users, including bicyclists, has become an increasing societal concern. Factors characterizing bicyclists’ crashes with motor vehicles may affect bicyclists’ injuries differently depending on the location of these crashes. The purpose of this paper is to provide a comprehensive analysis for identifying significant factors that affect bicyclists’ injury levels from crashes occurring at travel lanes and at non-travel lanes (e.g., crosswalks and bicycle lanes). For this purpose, this study applied Multinomial Logistic Regression on the Crash Report Sampling System data for three consecutive years. Bicyclists’ injuries were categorized into three levels: (1) Possible, (2) Moderate, and (3) Severe. The study found that running a separate model for each location provided better performances than running an aggregated model for both locations. Results showed common factors significantly associated with an increased likelihood of moderate and/or severe injuries at both locations. Five unique factors were associated with higher likelihoods of these moderate and/or severe injuries to bicyclists in the Travel Lane model, whereas two unique factors were found related to increased odds of these injuries to bicyclists in the Non-Travel Lane model. The results of this study contribute to a better understanding of bicyclists’ crash scenarios and the development of potential countermeasures by alternating some circumstances characterizing these crashes, when possible, to reduce potential injuries.
A Simple Analytical Solution for the Boussinesq One‐Dimensional Groundwater Flow Equation

An approximate analytical solution to the Boussinesq equation is presented here. Uniform initial conditions and a step function increase of piezometric head on the boundary are assumed. The one-dimensional problem is reduced to an ordinary differential equation through Boltzmann's transformation, and a technique exploiting some basic characteristics of the exact solution leads to an approximate polynomial solution of the problem. The technique presented here can also be applied to one-dimensional nonlinear diffusion problems. A numerical procedure incorporating some of the analytical characteristics of the exact solution is presented. A discussion concludes the paper.
The Large-Scale Circulation Change at the End of the Baiu Season in Japan as Seen in ERA40 Data

The time evolution of the circulation change at the end of the Baiu season is investigated using ERA40 data. An end-day is de? ned for each of the 23 years based on the 850 hPa θe value at 40˚Nin the 130? 140˚E sector exceeding 330 K. Daily time series of variables are composited with respect to this day. These composite time-series exhibit a clearer and more rapid change in the precipitation and the large-scale circulation over the whole East Asia region than those performed using calendar days. The precipitation change includes the abrupt end of the Baiu rain, the northward shift of tropical convection perhaps starting a few days before this, and the start of the heavier rain at higher latitudes.The northward migration of lower tropospheric warm, moist tropical air, a general feature of the seasonal march in the region, is fast over the continent and slow over the ocean. By mid to late July the cooler air over the Sea of Japan is surrounded on 3 sides by the tropical air. It is suggestive that the large-scale stage has been set for a jump to the post-Baiu state, i.e., for the end of the Baiu season. Two likely triggers for the actual change emerge from the analysis. The first is the northward movement of tropical convection into the Philippine region. The second is an equivalent barotropic Rossby wave-train, that over a 10-day period develops downstream across Eurasia. It appears likely that in most years one or both mechanisms can be important in triggering the actual end of the Baiu season.
Pulse evolution without wave breaking in a strongly dissipative-dispersive laser system

We report on pulse evolution without wave breaking in a strongly dissipative-dispersive laser system where pulses encounter significant amounts of positive and negative dispersions. in contrast to conventional soliton, dispersion-managed soliton, and self-similar pulse evolutions, a different type of pulse shaping in mode-locked lasers is theoretically investigated and experimentally observed. the pulses of this laser have very low frequency chirp and exhibit as the quasirectangle temporal and gaussian spectral profiles, and the spectral width is almost independent of the pumping strength. the temporal and spectral widths fluctuate as low as similar to 3% of the relative fluctuation throughout the laser cavity. both numerical and experimental results show that the pulses exist with energies much greater than can be tolerated in self-similar pulse shaping.
Learning challenges during the COVID-19 lockdown, motivation, and perseverance: a triadic model of Saudi students

ABSTRACT This cross-sectional study aims to investigate the relationships between learning challenges during the COVID-19 lockdown, motivation, and perseverance in one statistical triadic model. Two hundred and thirty-eight Saudi students (undergraduates and graduates) studying different subjects from eight universities completed a structured questionnaire. Confirmatory factor analysis and structural equation modelling were used in the data analysis. The results revealed that the measurement model and the structural model fit the data well (CFI = 0.943; TLI = 0.918; RMSEA [90% confidence interval] = 0.059 [0.032–0.091]; SRMR = 0.071). Learning challenges during the COVID-19 lockdown were positively linked to students’ motivation and perseverance, and the latter two were also related positively – all the relationships were significant. The findings of this study could help policy makers activate e-learning and hybrid learning more successfully than before the pandemic and will help educators to improve their technology skills, which, in turn, will improve the learners’ motivation and perseverance.
Errors Caused by Long-Term Drifts of Magnetron Frequencies for Refractivity Measurement with a Radar: Theoretical Formulation and Initial Validation

Refractivity measurements in the boundary layer by precipitation radar could be useful for convection prediction. Until now such measurements have only been performed by coherent radars but European weather radars are mostly equipped with non-coherent magnetron transmitters, for which the phase and frequency may vary. In this paper, we give an analytical expression of the refractivity measurement by a non-coherent drifting-frequency magnetron radar and we validate it by comparing with in-situ measurements. The main conclusion is that, provided the necessary corrections are applied, the measurement can be successfully performed with a non-coherent radar. The correction factor mainly depends on the local-oscillator frequency variation, which is known perfectly. A second-order error, proportional to the transmitted frequency variation, can be neglected as long as this change remains small.
The Effect of Epidural Infusion of Dexmedetomidine on Postoperative Analgesia After Thoracotomy: A Randomized Clinical Trial

Background The unique analgesic properties of dexmedetomidine have led anesthesiologists to use it as an alternative to relieve pain after major surgeries. Objectives We aimed to evaluate the effect of continuous injection of thoracic epidural dexmedetomidine on analgesia after thoracotomy. Methods In this randomized, double-blind clinical trial, 46 patients (18 to 70 years old) who were candidates for thoracotomy surgery were randomly assigned to receive ropivacaine alone or combined with dexmedetomidine after epidural anesthesia as postoperative epidural anesthesia. The postoperative sedation rate, pain score, and opioid use were assessed within 48 hours after surgery and compared between the 2 groups. Results Comparing the mean postoperative sedation scores indicated no difference between the 2 study groups. The pain score assessment showed a lower pain score 6 to 36 hours after surgery in the group receiving concurrent ropivacaine and dexmedetomidine than in the group receiving ropivacaine alone. In the 2 groups receiving ropivacaine with and without dexmedetomidine, the rate of morphine administration after surgery was 43.4% and 65.2%, respectively, indicating no difference. However, the first group received significantly lower doses of morphine after the end of surgery (3.26 ± 0.90 mg vs. 7.04 ± 1.48 mg; P = 0.035). Conclusions A combination of ropivacaine and dexmedetomidine as epidural analgesia can lead to lower postoperative pain scores and reduced doses of opioids required.
Free‐surface flow over curved surfaces: Part II: Computational model

SUMMARY In Part I a detailed derivation of a more general shallow water equation set was developed via a perturbation analysis. A finite element computational model of these more general equations is now constructed and the model behavior is compared with conventional shallow water formulations applied to an outletworks flume. © 1998 John Wiley & Sons, Ltd. The momentum equations derived in Part I are in non-conservative form and are written for a specific distance above the bed to include effects due to curvature. The standard two-dimensional shallow water equation formulation assumes a mild bed slope and no curvature effect. These assumptions limit the applicability of these equations for some important classes of problems. In particular, flow over a spillway is indeed affected by the bed curvature via a decidedly non-hydrostatic pressure distribution. In Part II these equations are depth-integrated and incorporated in a computational model. This form of the equations may be useful in handling non-smooth conditions. The weak form solution for the no-curvature condition that would be encountered downstream of the spillway can be made to properly conserve momentum and mass through a hydraulic jump, whereas other forms of the equations may not. In the case in which there is bed curvature, these equations will contain additional terms due to the bed curvature which, while finite through the jump, will make an additional contribution that can cause an error in the jump location. Therefore, in the vicinity of the jump these equations, which properly conserve mass and momentum for the no-curvature case, will conserve mass precisely in the curved bed state only. Generally, in practical cases the strong jump is restricted to the region downstream of the spillway face where the bed contains no curvature. Several recent finite element schemes for the shallow water equations utilize the Petrov‐ Galerkin approach [1,2] and are considered in Reference [3]. Such a scheme is constructed here for the system developed in Part I to handle bed curvature effects. The treatment proceeds as follows: first the model equations are summarized and an appropriate test function is devised. Next, the finite element Petrov‐Galerkin system is presented and the treatment of boundary * Correspondence to: USAE Waterways Exp. Station, Vicksburg, MS, USA.
The Photodissociation and Ionization Fronts in M17-SW Localized with FIFI-LS on Board SOFIA

To understand star formation rates, studying feedback mechanisms that regulate star formation is necessary. The radiation emitted by nascent massive stars play a significant role in feedback by photodissociating and ionizing their parental molecular clouds. To gain a detailed picture of the physical processes, we mapped the photodissociation region (PDR) M17-SW in several fine-structure and high-J CO lines with FIFI-LS, the far-infrared imaging spectrometer aboard SOFIA. An analysis of the CO and [O i]146 μm line intensities, combined with the far-infrared intensity, allows us to create a density and UV intensity map using a one-dimensional model. The density map reveals a sudden change in the gas density crossing the PDR. The strengths and limits of the model and the locations of the ionization and photodissociation front of the edge-on PDR are discussed.
Estimation of Life’s Essential 8 Score with Incomplete Data of Individual Metrics

Background: The American Heart Association's Life's Essential 8 (LE8) is an updated construct of cardiovascular health (CVH), including blood pressure, lipids, glucose, body mass index, nicotine exposure, diet, physical activity, and sleep health. It is challenging to simultaneously measure all eight metrics at multiple time points in most research and clinical settings, hindering the use of LE8 to assess individuals' overall CVH trajectories over time. Methods and Results: We obtained data from 5,588 participants in the Nurses' Health Studies (NHS, NHSII) and Health Professional's Follow-up Study (HPFS), and 27,194 participants in the 2005-2016 National Health and Nutrition Examination Survey (NHANES) with all eight metrics available. Individuals' overall cardiovascular health (CVH) was determined by LE8 score (0-100). CVH-related factors that are routinely collected in many settings (i.e., demographics, BMI, smoking, hypertension, hypercholesterolemia, and diabetes) were included as predictors in the base models of LE8 score, and subsequent models further included less frequently measured factors (i.e., physical activity, diet, blood pressure, and sleep health). Gradient boosting decision trees were trained with hyper-parameters tuned by cross-validations. The base models trained using NHS, NHSII, and HPFS had validated root mean squared errors (RMSEs) of 8.06 (internal) and 16.72 (external). Models with additional predictors further improved performance. Consistent results were observed in models trained using NHANES. The predicted CVH scores can generate consistent effect estimates in associational studies as the observed CVH scores. Conclusions: CVH-related factors routinely measured in many settings can be used to accurately estimate individuals' overall CVH when LE8 metrics are incomplete.
The return to isotropy of an homogeneous turbulence having been submitted to two successive plane strains

The authors consider an homogeneous non-isotropic turbulence which develops without mean velocity gradient so that it should return to isotropy. This turbulence has been obtained by application of two successive plane strains to a grid-generated turbulence, and this configuration has already been described in a preceding paper. It is shown in particular that the nonlinear effects make no significant contribution to the rotation of the principal axes of the Reynolds stress tensor. In the case of the return to isotropy, an important parameter connected with the turbulent energy distribution between three directions comes into play. In the present experiment it has a positive sign whereas in previous experiments this sign was negative. In particular, the authors conclude that, when this parameter is positive, the return to isotropy is slower than in the opposite case.
Identification of new low‐mass members of the Alpha Persei open cluster by ROSAT. II

The present investigation examines possible optical counterparts to 130 X-ray sources in the region of the α Persei open cluster (d ∽ 170pc, age ∽ 50 Myr) resulting from the analysis of three 22–25 ksec ROSAT PSPC pointings. In the same manner as for 73 X-ray sources from a raster survey in α Per (Prosser & Randich 1998), CCD photometry is employed to obtain magnitudes and colors for stars/objects close to the X-ray positions, with additional echelle and low-dispersion Hα spectra provided for some stars. For almost 60 X-ray sources, an optical counterpart with photometry acceptable for cluster membership is identified, some of which can be excluded from membership on the basis of discrepant radial velocity or X-ray characteristics. On the order of 30 new members or likely members associated with X-ray sources have been identified based on available data. A photometric rotation period has been obtained for one rapid rotator identified in X-rays.
Dislocation Stresses in a Thin Film Due to the Periodic Distributions of Dislocations

The state of stresses and displacements in thin films due to the presence of a periodic distribution of screw dislocations and edge dislocations is investigated by the method of continuously distributed dislocations and the three‐dimensional theory of elasticity. The dislocations are straight and pierce obliquely the surfaces of the thin films in both cases. As a special case the exact solution is presented for a straight‐edge dislocation piercing normally the surfaces of the films. Emphasis is placed upon the stress relaxation caused by the presence of free surfaces. The result will be useful for the contrast study of dislocation images in electron microscopy.
Effects of heat release on turbulent shear flows. Part 2. Turbulent mixing layers and the equivalence principle

The general equivalence principle of Tacina & Dahm (2000) (Part 1) that extends scaling laws for non-reacting flows to account for density changes due to reaction heat release is applied to turbulent mixing layers to develop physically based scaling laws for heat release effects in exothermic reacting mixing layers. This leads to an ‘extended density ratio’ $s^+$ based on the equivalent elevated temperature for one of the two free-stream fluids that accounts for the density variations within the layer due to exothermic reaction. When used in place of the isothermal density ratio $s$ in scaling laws for growth rate and entrainment ratio in non-reacting mixing layers, resulting predicted effects of heat release show good agreement with measured values, and reveal subtle effects of stoichiometry previously unnoticed in experiments. Results also suggest ways to achieve increased growth rates and entrainment ratios due to heat release in turbulent mixing layers. These results for heat release effects in mixing layers, and earlier results for heat release effects in the near and far fields of planar and axisymmetric jets, support the validity and utility of the equivalence principle between exothermic reacting turbulent shear flows and a corresponding equivalent non-reacting flow under otherwise identical conditions.
The dry intrusion perspective of extra‐tropical cyclone development

The dry intrusion is a coherent region of air descending from near tropopause‐level. It often has a clear signature in satellite imagery, especially in the water vapour channel, where it is seen as a ‘dark zone’. Parts of dry intrusions are characterised by high potential vorticity and, upon approaching a low‐level baroclinic zone, rapid cyclogenesis may be expected to ensue. The leading edges of dry intrusions are defined by cold θw‐fronts (moisture fronts). In some places the dry intrusion undercuts rearward‐ascending warm air to give an ana‐cold front. In other places it overruns the warm air to produce an upper cold θw‐front in advance of the surface cold frontHere the dry intrusion is associated with the generation of potential instability and its eventual release as showers or thunderstorms. Identification of dry intrusions provides the forecaster with additional nowcasting evidence that is especially helpful when issuing severe weather warnings. The identification of water vapour dark zones associated with dry intrusions can also form the basis of methods for validating NWP models. Through their relationship to high potential vorticity, they can provide guidance for bogussing NWP models in situations of potentially severe weather. This article provides an introduction to the structure and behaviour of dry intrusions and their relationship to other aspects of extra‐tropical cyclones. Copyright © 2004 Royal Meteorological Society
The Markov branching process with density-independent catastrophes. III. The supercritical case

This paper continues the study initiated in [9] of the Markov branching process (MBP) with a density-independent catastrophe component. The population size process (Xt) was investigated in the subcritical and critical cases in [11], and the present paper is concerned with a parallel investigation of the supercritical case. We refer the reader to [11] for definitions and notation, and we will not repeat them here.
Vortex equilibrium in flows past bluff bodies

The equilibrium conditions of a point vortex in the separated flow past a locally deformed wall is studied in the framework of the two-dimensional potential flow. Equilibrium locations are represented as fixed points of the vortex Hamiltonian contour line map. Their pattern is ascribable to the Poincaré–Birkhoff fixed-point theorem. An ‘equilibrium manifold’, representing the generalization of the Föppl curve for circular cylinders, is defined for arbitrary bodies. The property $\partial\omega/\partial\skew3\tilde\psi\,{=}\,0$ holds on it, with $\skew3\tilde\psi$ being the stream function and $\omega$ the streamline slope of the pure potential flow. A ‘Kutta manifold’ is defined as the locus of vortices in flows that separate at a prescribed point (Kutta condition). The existence of standing vortices that satisfy the Kutta condition is discussed for symmetric bodies. On the basis of an asymptotic expansion of the equilibrium manifold, Kutta manifold and body geometry, it is shown that different classes of symmetric bodies exist which are ranked by the number of allowable standing vortices that satisfy the Kutta condition.