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Background: As perception of penile curvature varies widely, we sought to understand how adults perceive curvature and how these opinions compare with those of patients with curvature, specifically Peyronie's disease (PD). Aim: To investigate the perspectives of curvature correction from adults with and without PD, as well as differences within demographics. Methods: A cross-sectional survey was administered to adult patients and nonpatient companions in general urology clinics at 3 institutions across the United States. Men, women, and nonbinary participants were recruited. Patients were grouped as having PD vs andrology conditions without PD vs general urology conditions plus companions. The survey consisted of unlabeled 2-dimensional images of penis models with varying degrees of curvature. Participants selected images that they would want surgically corrected for themselves and their children. Univariable and multivariable analyses were performed to identify demographic variables associated with willingness to correct. Outcomes: Our main outcome was to detect differences in threshold to correct curvature between those with and without PD. Results: Participants were grouped as follows: PD (n = 141), andrology (n = 132), and general (n = 302). Respectively, 12.8%, 18.9%, and 19.9% chose not to surgically correct any degree of curvature (P = .17). For those who chose surgical correction, the mean threshold for correction was 49.7°, 51.0°, and 51.0° (P = .48); for their children, the decision not to correct any degree of curvature was 21.3%, 25.4%, and 29.3% (P = .34), which was significantly higher than correction for themselves (P < .001). The mean threshold for their children's correction was 47.7°, 53.3°, and 49.4° for the PD, andrology, and general groups (P = .53), with thresholds no different vs themselves (P = .93). On multivariable analysis, no differences were seen in demographics within the PD and andrology groups. In the general group, participants aged 45 to 54 years and those who identified as LGBTQ (lesbian, gay, bisexual, transgender, queer) had a higher threshold for correction as compared with their counterparts when factoring other demographic variables (63.2° vs 48.8°, P = .001; 62.1° vs 50.4°, P = .05). Clinical Implications: With changing times and viewpoints, this study stresses the importance of shared decision making and balancing risks and benefits to correction of penile curvature. Strengths and Limitations: Strengths include the broad population surveyed. Limitations include the use of artificial models. Conclusion: No significant differences were seen in the decision to surgically correct curvature between participants with and without PD, with participants being less likely to choose surgical correction for their children. [ABSTRACT FROM AUTHOR]

Vehicle run-off-road is one of the most frequent and fatal traffic accidents in the United States. Various lane-keeping assistance (LKA) systems have been developed in the last decade to help drivers stay on the road. Most of them are built upon linear driver–vehicle–road (DVR) models and treat road curvature as a disturbance. Albeit effective, their control performance would degrade if road curvature varies rapidly. This paper proposes a novel nonlinear DVR model by integrating a driver steering model into vehicle–road kinematics, which explicitly considers road curvature. Particularly, this nonlinear DVR system has been proven to be differentially flat, and a flatness-based LKA system is designed. Additionally, Model-Free Control is introduced to compensate for system modeling errors. Hardware-in-the-loop simulations and diver-in-the-loop experiments validate the proposed control framework and demonstrate the performance enhancement with respect to a representative linear robust LKA system. • A novel lane-keeping assistance system based on a nonlinear driver–vehicle–road (DVR) model. • Proofing the DVR model is differentially flat. • Algebraically estimating the flat output's derivatives without relying on the DVR model. • Introducing Model-Free Control to compensate for modeling errors. • Hardware-in-the-loop simulations and driver-in-the-loop experiments validating the performance. [ABSTRACT FROM AUTHOR]

Abstract: For most fluids, there exist a maximum and a minimum in the curvature of the reduced vapor pressure curve, (with and and being the pressure and temperature at the critical point). By analyzing National Institute of Standards and Technology (NIST) data on the liquid-vapor coexistence curve for 105 fluids, we find that the maximum occurs in the reduced temperature range while the minimum occurs in the reduced temperature range . Vapor pressure equations for which diverges at the critical point present a minimum in their curvature. Therefore, the point of minimum curvature can be used as a marker for the critical region. By using the well-known Ambrose–Walton (AW) vapor pressure equation we obtain the reduced temperatures of the maximum and minimum curvature in terms of the Pitzer acentric factor. The AW predictions are checked against those obtained from NIST data. [Copyright &y& Elsevier]

Existing and proposed models of the effective stiffness of reinforced concrete columns subjected to lateral loads are assessed using the experimental response of 329 concrete columns. Existing models appropriate for design applications tend to overestimate the measured effective stiffness and are unacceptably inaccurate, because they generally neglect the influence of anchorage slip on the effective stiffness of the column. A three-component model that explicitly accounts for deformations due to flexure, shear, and anchorage-slip is shown to provide a more accurate estimate of the measured effective stiffness for the database columns. This model is simplified by neglecting small terms and approximating the results of moment-curvature analysis to obtain an accurate and rational effective stiffness model appropriate for design applications. For this model, the ratio of the measured stiffness to the calculated stiffness had a mean and coefficient of variation of 1.02 and 22% for circular columns and 0.95 and 25% for rectangular columns. [ABSTRACT FROM AUTHOR]

While digital map has been applied to many advanced driver assistance system applications, one critical attribute - road/lane curvature—is not available in the existing digital maps. Curvature derivation using splines is a well-known method in the computer graphics modelling community; however, it was also found that the direct application of the spline method is often not appropriate for real-time safety applications due to the resultant discontinuities in the curvature estimates and the lack of robustness against map data errors [CAMP, Enhanced digital mapping project final report, United States Department of Transportation, Washington, DC, 2004]. This paper presents a method to reconstruct road curvature attributes in real time using digital map data based on the proposed circle centre search and circle selection algorithms. Simulation and experimental results demonstrated that the proposed method can deliver curvature estimates that meet the desired accuracy. The method was also applied to the curve over-speed warning system in an on-going research project: Vehicle Infrastructure Integration—California. Some preliminary experimental results are also presented in this paper. [ABSTRACT FROM AUTHOR]

In this paper, we estimate a mixed logit model for demand in the U.S. processed cheese market. The estimates are used to determine pass-through rates of cost changes under different behavioral regimes. We find that, under collusion, the pass-through rates for all brands fall between 21% and 31% while, under Nash-Bertrand price competition, the range of pass-through rates is between 73% and 103%. The mixed logit model provides a more flexible framework for studying pass-through rates than the logit model since the curvature of the demand functions depends upon the empirical distribution of consumer types. [ABSTRACT FROM AUTHOR]

In this paper, flexural behavior of horizontally curved prestressed (posttensioned) box bridges is studied by using three-dimensional and refined finite-element modeling and analysis. Bridge length, section geometry, and material properties are the same in all the models, while angle of curvature varies from 0 to 90°. The results of analysis show that in curved bridges, stress distribution is significantly different in comparison to straight bridges. Also, the level of stresses at some locations of section width is considerably high. It is proposed to vary the distribution of the prestressing tendons across section width in order to optimize the bridge capacity. Results show that by proper redistribution of prestressing in section width, significant reduction in resultant stress is possible. [ABSTRACT FROM AUTHOR]

This paper focuses on the demand for money in the United States in the context of five popular locally flexible functional forms—the generalized Leontief, the basic translog, the almost ideal demand system, the Minflex Laurent, and the normalized quadratic reciprocal indirect utility function. We pay explicit attention to the theoretical regularity conditions of positivity, monotonicity, and curvature and argue that much of the older empirical literature ignores economic regularity. We treat the curvature property as a maintained hypothesis and provide a comparison in terms of violations of the regularity conditions and in terms of output in the form of a full set of elasticities. We also provide a policy perspective, in that a strong case can be made for abandoning the simple sum approach to monetary aggregation, on the basis of the low elasticities of substitution among the components of the popular M2 aggregate of money. [ABSTRACT FROM AUTHOR]

New compilations of geometry and tectonic transport in the Pennsylvania salient suggest that these features continue uninterrupted from the Piedmont through the Valley and Ridge provinces. These data are the basis for a new two-azimuth transport model for origin of the curvature. Edge geometry of an Eocambrian craton and a thickened stratigraphy acted as templates for Alleghanian regional décollement, first as Reading Prong ∼N35°W motion, followed by ∼N68°W Blue Ridge motion. Both displacements involved some drag rotation and overprinting in a central zone. This model avoids the problem of minimal tangential stretching, explains the anthracite basins as trailing-edge graben and basin structures against the autochthonous Pocono Plateau, and produces the Nittany- Juniata culmination as an overprinted pileup of duplexes in the central zone. The model of detachment followed by changing azimuth of motion of a megadécollement sheet may apply to other salients throughout the world. [ABSTRACT FROM AUTHOR]

This paper presents a detailed investigation of warping-related stresses in 18 composite steel-concrete box girder bridges. The bridge designs were adapted from blueprints of existing bridges in the state of Florida and encompass a wide range of parameters including horizontal curvature, cross-sectional properties, and number of spans. The bridges after which the analysis prototypes are modeled were designed by different firms and constructed at different times and are considered to be representative of current design practice. Forces are evaluated from analyses that account for the construction sequence and the effect of warping. Loading is considered following the 1998 AASHTO-LRFD provisions. Differences between stresses obtained taking warping into account and those calculated by ignoring warping are used to evaluate the effect of warping. Analysis results show that warping has little effect on both shear and normal stresses in all bridges. Current design provisions are discussed in light of the analysis results. [ABSTRACT FROM AUTHOR]

A typical industrial steel structure located near Kansas City, Missouri, is reviewed for structural integrity. The structure provides support to heavy production equipment and is in the last stage of construction. The review finds this facility structurally unsound because of excessive lateral displacements. It is in danger of collapsing under the combined effect of dead load, heavy load, and peak wind load. Although it appears more economical to rebuild the structure, for political reasons the manufacturer rules out the rebuild option. As a result, an extensive retrofit effort is conducted to the structure immediately following the review. This paper discusses some of the review findings and the challenges they pose for the retrofit effort. It describes the strategy used to address or circumvent some of the difficulties. The behaviors of the structure before and after the retrofit are compared to illustrate the basic concept and the effectiveness of the retrofit effort. [ABSTRACT FROM AUTHOR]

This paper provides a historical overview of the development of horizontally curved steel I girder bridge design specifications in the United States. The background to the development of curved I girder design and analysis provisions in the 1993 and 2003 AASHTO Guide Specifications for Horizontally Curved Highway Bridges is discussed, and the status of recently completed and ongoing curved steel bridge research projects is summarized. In addition, the manuscript focuses on how the 2003 Guide Specifications can be used to analyze and design horizontally curved I girder bridges. Comparisons are made to prior provisions in the 1993 Guide Specifications. [ABSTRACT FROM AUTHOR]

Proposes and empirically tests methods for imposing curvature conditions globally in the context of cost function estimation. Description of the proposed methods; Estimation of translog cost function and generalized cost functions; Data from the U.S. manufacturing sector.

New improved reference equations for cardiorespiratory fitness have recently been published, using Data from the Fitness Registry and the Importance of Exercise National Database (FRIEND Registry). The new linear equation for VO 2max (ml.kg -1 .min -1 ) was additive, derived using multiple-linear regression. An alternative multiplicative allometric model has also been published recently, thought to improve further the quality of fit. The purpose of the current study was to compare the accuracy and quality/goodness-of-fit of the linear, additive model with the multiplicative allometric model using the FRIEND database. The results identified that the allometric model out performs the linear model based on all model-comparison criteria. The allometric model demonstrates; 1) greater explained variance (R 2  = 0.645; R = 0.803) vs. (R 2  = 0.62; R = 0.79), 2) residuals that were more normally distributed, 3) residuals that yielded less evidence of curvature, 4) superior goodness-of-fit statistics i.e., greater maximum log-likelihood (MLL) and smaller Akaike Information Criterion (AIC) statistics, 5) less systematic bias together with smaller unexplained standard error of estimates. The Bland and Altman plots also confirmed little or no evidence of curvature with the allometric model, but systematic curvature (lack-of-fit) in the linear model. The multiplicative allometric model to predict VO 2max was; VO 2max (ml.kg -1 .min -1 ) = M -0.854 · H 1.44 · exp. (0.424-0.346 · (sex) -0.011.age), where M = body mass and H = height (R 2  = 0.645; R = 0.803) and sex is entered as a [0,1] indicator variable (male = 0 and female = 1). Another new insight obtained from the allometric model (providing construct validity) is that the height-to-body-mass ratio is similar to inverse body mass index or the lean body mass index, both associated with leanness when predicting VO 2max . In conclusion adopting allometric models will provide more accurate predictions of VO 2max (ml.kg -1 .min -1 ) using more plausible, biologically sound and interpretable models., Competing Interests: Declaration of competing interest The authors have no conflicts of interest., (Copyright © 2019 Elsevier Inc. All rights reserved.)

This is the first upright magnetic resonance imaging study to document reduced disc height and greater lumbar asymmetry with common backpack loads in children. [ABSTRACT FROM AUTHOR]