bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical characteristics of and antibody response to spotted fever group rickettsial infections in South India: Case series and serological cohort study
Authors: Schmidt Wolf‐Peter , Devamani Carol S. , Elangovan Divyaa , Alexander Neal , Rose Winsley , Prakash John A. J. 
Published: October 2021

AbstractObjectiveThe clinical and serological characteristics of spotted fever group rickettsial (SFGR) infections in South Asia are poorly understood. We studied the clinical presentation and the IgM/IgG response in cases enrolled at two health care centres in South India.MethodWe enrolled 77 patients. Fifty‐seven of these patients were recruited at a tertiary care centre, the remaining 20 at a community hospital (secondary care level). Diagnostic tests included IgM and IgG enzyme‐linked immunosorbent assay and polymerase chain reaction. Over a period of 1 year, 41 cases were followed up for repeated sero‐analysis.ResultsMedian age was 9 years (range 1–79). A rash was present in 74% of cases (57/77). In cases aged <15 years, rash was present in 94% (44/47) vs. 43% (13/30) in cases aged ≥15 years. An eschar was found in two cases (3%). Severe infection or complications occurred in 10 cases (13%). These included central nervous system infection (6/77, 8%), kidney injury (3/77, 4%), shock (3/77, 4%), lung involvement (2/77, 3%) and peripheral gangrene (2/77, 3%). IgM antibody levels increased faster after fever onset than IgG antibodies, peaking at 50 and 60 days, respectively. After the peak, IgM and IgG levels showed a slow decline over one year with less than 50% of cases showing persistent IgG antibody levels.ConclusionSpotted fever group rickettsial infections in South India may be under‐diagnosed, as many cases may not develop a rash. The proportion of cases developing severe infection seems lower than for scrub typhus in this region. IgG seroprevalence may substantially underestimate the proportion in a population with past SFGR infection.
Pet‐owner perceptions of laparoscopy in an urban hybrid veterinary practice
Authors: Buote Nicole J. , Carney Patrick , Sumner Julia 
Published: October 2021

AbstractObjectiveTo investigate owner perceptions of laparoscopic surgery, including attitudes towards paying more for minimally invasive surgery (MIS).Study designRandomized cross‐sectional prospective survey.Sample populationOne hundred owners presenting at a combined general and specialty practice.MethodsParticipants were interviewed using a survey tool to assess prior knowledge of laparoscopic procedures, attitude for or against these procedures, reasons for this attitude, and whether they would pay more for the procedures. Demographic data were collected.ResultsFifty‐five percent of owners had previous knowledge of laparoscopy. Ninety‐two percent of owners would choose laparoscopy over an open procedure for their pet. Reasons given for preferring laparoscopy: less postoperative pain (66.3%), shorter length of hospitalization (26.1%), better cosmesis (20.1%), perception of lower cost (15.2%), faster return to function (14.1%), length of anesthesia (5.4%), and other reasons (26.1%). Ninety‐one percent of owners were willing to pay more for MIS. Among owners who indicated they would be willing to pay more, owners presenting with dogs were 2.5 times more likely to be willing to pay at least $1000 more than owners presenting with cats.ConclusionThe majority of owners surveyed at a large hybrid hospital in an urban setting choose laparoscopic over open procedures and were willing to pay more for them.Clinical significanceThe results highlight the importance of client and veterinarian education regarding the options of MIS for pets, as owners who are informed may prefer referral for the procedures. The financial investment to build a MIS practice may be justified.
Using Smartphones for Clinical Assessment in Cervical Spondylotic Myelopathy a Feasibility Study
Authors: Zaldivar-Jolissaint Julien Francisco , Lechanoine François , Krummenacher Bernard , Arruda Rivus Ferreira , Bobinski Lukas , Schlichting Emmanuel de , Duff John Michael 
Published: October 2021

Abstract
Degenerative cervical myelopathy (DCM) is characterized by a progressive deterioration in spinal cord function. Its evaluation requires subjective clinical examination with wide interobserver variability. Objective quantification of spinal cord function remains imprecise, even though validated myelopathy-grading scales have emerged and are now widely used. We created a Smartphone Application, the N-Outcome App, with the aim of quantifying accurately and reliably spinal cord dysfunction using a 5-minute Test. A patient suffering from DCM was clinically evaluated before surgery, at 3 and 6 months follow-up after surgical decompression of the cervical spinal cord. Standard scores (Nurick grade, modified Japanese Orthopedic Association (mJOA) score) were documented at these time points. A 5-minute motor and proprioceptive performance test aided by a smartphone with the N-outcome App was also performed. Motor performance in rapid alternating movements and finger tapping improved in correlation with improvements in standard grading scale scores. Clinical improvements were seen in maximum reflex acceleration and in Romberg testing which showed less closed/open eyes variation, suggesting pyramidal and proprioceptive function recovery. We demonstrate that using the N-Outcome App as an adjunct to clinical evaluation of compressive myelopathy is feasible and potentially useful. The results correlate with the results of clinical assessment obtained by standard validated myelopathy scores.
A Numerical and Experimental Study of the Time-Averaged and Transient Flow Downstream of a Butterfly Valve
Authors: Tao Junyu , Lin Zhe , Zhang Guang , Su Jingpan , Zhu Zuchao 
Published: October 2021

Abstract
This research took the DN50 butterfly valve as the research object and studied the flow situation of butterfly valves with different shafts. The resistance characteristics, flow state, characteristics, and flow instability of butterfly valves with different structures were studied by experiments and numerical simulations. Research shows that the flow separation occurs at the edge of the valve disk, and the drag of the valve disk fluctuates nonperiodically with time. Under different opening degrees, the velocity distribution downstream of the valve varies, and the effect of the shaft on the velocity fluctuation is different. Finally, the unstable region of flow downstream of the valve is determined. This study provides a reference for the use and optimization of butterfly valves.
Effects of Different Friction Coefficients on Input Torque Distribution in the Bolt Tightening Process Based on the Energy Method
Authors: Jiang Kai , Liu Zhifeng , Wang Yida , Tian Yang , Zhang Caixia , Zhang Tao 
Published: October 2021

Abstract
Bolted joints are one of the most common fastening methods in engineering applications. To meet the requirements of structural parts, the torque method is often used for controlling the bolted joint performance. However, only a few investigations have been carried out on the conversion efficiency of bolt torque to the tensile force, leading to uncertainty and potential safety hazards during the bolt tightening. In order to study the input torque distribution and overcome problems caused by the Motosh method and experimental investigations, a new energy-based torque distribution model is established in the present study. In the proposed model, numerous affecting parameters, including the connector compression work, effective bearing radius, effective thread contact radius, and spiral angle are considered. Then a parameterized thread mesh model using finite element technology is proposed to analyze the influence of different bolt friction coefficients on the bolt tightening process. Based on 16 types of tightening analyses, it is concluded that as bolt friction coefficient increases, the corresponding torque conversion rate decreases from 14.45% to 7.89%. Compared with the Motosh method, the torque conversion rate obtained by the proposed method is relatively large, which makes the actual pre-tightening force larger than the design value. However, there is still a possibility of bolt failure.
Effects of Wing Kinematics on Modulating Odor Plume Structures in the Odor Tracking Flight of Fruit Flies
Authors: Lei Menglong , Li Chengyu 
Published: October 2021

Abstract
Insects rely on their olfactory system to forage, prey, and mate. They can sense odorant plumes emitted from sources of their interests with their bilateral odorant antennae, and track down odor sources using their highly efficient flapping-wing mechanism. The odor-tracking process typically consists of two distinct behaviors: surging upwind and zigzagging crosswind. Despite the extensive numerical and experimental studies on the flying trajectories and wing flapping kinematics during odor tracking flight, we have limited understanding of how the flying trajectories and flapping wings modulate odor plume structures. In this study, a fully coupled three-way numerical solver is developed, which solves the 3D Navier-Stokes equations coupled with equations of motion for the passive flapping wings, and the odorant convection-diffusion equation. This numerical solver is applied to investigate the unsteady flow field and the odorant transport phenomena of a fruit fly model in both surging upwind and zigzagging crosswind cases. The unsteady flow generated by flapping wings perturbs the odor plume structure and significantly impacts the odor intensity at the olfactory receptors (i.e., antennae). During zigzagging crosswind flight, the differences in odor perception time and peak odor intensity at the receptors potentially help create stereo odorant mapping to track odor source. Our simulation results will provide new insights into the mechanism of how fruit flies perceive odor landscape and inspire the future design of odor-guided micro aerial vehicles (MAVs) for surveillance and detection missions.
Numerical Analysis on the Flow Bifurcation and Heat Transfer Regulation in the Constricted Cavity Under the Transverse Magnetic Field Using OpenFOAM
Authors: Singh Ranjit J. , Gohil Trushar B. 
Published: October 2021

Abstract
In this study, the heat transfer pattern and flow bifurcation in the fluid is observed by the application of low intensity magnetic field in the gradually constricted cavity. The natural convection flow solver with Lorentz force and Boussinesq approximation as a source term is developed in the open-source CFD platform OpenFOAM. The Lorentz force in the flow is altered by varying the Hartmann number of Ha = 0 – 100, however the buoyancy force is kept constant in the flow at fixed Rayleigh number of Ra = 106. The orientation of magnetic field is exposed to be in the y-direction (By). The significance of using the By magnetic field with its various intensity in the constricted enclosure on the heat transfer and flow pattern is reported. It is perceived that the transverse magnetic field (By) and its varying intensity regulates the heat transfer with multiple convection rings. The detail study on the isotherms, streamlines, and the time average Nusselt number is reported.
CFD Analysis of Refrigeration Cycle Ejector
Authors: Forster Franz X. , Deravanessian Alexander E. , Nazarian Matthew J. , Rubio Mariano , Anderson Kevin R. 
Published: October 2021

Abstract
The use of ejector cycles for increased performance and efficiency is becoming more prevalent in industry. The goal of this study is to evaluate an ejector using Computational Fluid Dynamics (CFD) to evaluate flow patterns, perform trade studies varying the type of refrigerant, and determine the entrainment ratio for each working fluid, over a range of boundary condition pressures, set at points along the ejector’s flow path. The 2012 Toyota Prius V is one of the first automobiles using an ejector cycle in their internal cabin refrigeration system. The DENSO Corporation ejector hardware was used as the basis for the creation of geometry for the CFD mode of the ejector. Three working fluids were simulated, R-134a, R-245fa, and R-1235yf. The primary findings of this study were as follows. The CFD study here indicates that R-245fa performs the best out of the three working fluids, when examining their entrainment ratios (ratio of secondary to primary flow rates in the ejector). For all three working fluids, the entrainment ratio was seen to peak performance at an ejector inlet pressure of 1.75 × 105 Pa. The ejector mixing chamber pressure and ejector outlet pressure boundary conditions also witnessed a rise in entrainment ratios, during an increase of their respective pressure values.
Teaching Limiting Behavior of Plane Oblique Shocks
Authors: Farokhi S. , Taghavi R. 
Published: October 2021

Abstract
Plane oblique shocks are formed in supersonic flows that cause abrupt flow deceleration, compression and turning. This behavior persists up to a maximum flow turning angle, θmax and a corresponding shock angle βmax for any upstream Mach number M1 with corresponding Mach angle, μ1. Beyond the maximum turning angle, the oblique shock becomes detached from the body and forms a bow shock. In teaching limiting behavior of plane oblique shocks, over a broad Mach range, from 1.5 to 5.0, we discover two interesting correlations. The first is on βmax which remains nearly invariant and the second is (μ1 + θmax) that remains nearly constant. In air with γ = 1.4, βmax is nearly 65.64° with 0.67° standard deviation and (μ1 + θmax) is nearly 53.24° with 0.32° standard deviation angle. Rankine-Hugoniot and Prandtl oblique shock relations are used in theoretical demonstrations of limiting behavior of plane oblique shocks.
Behavior of Cell Under Wall Shear Stress in Flow Field: Comparison Among Cell Types
Authors: Hashimoto Shigehiro , Yoshinaka Kiyoshi , Yonezawa Hiroki 
Published: October 2021

Abstract
Does the hysteresis effect remain in each cell after division? In the present study, the cell activity has been investigated after division under a shear stress field. To apply the constant shear stress field on cells, a Couette type flow device has been manufactured: between parallel walls (a lower stationary culture disk, and an upper rotating disk) with a constant gap. The wall shear stress was controlled by the rotating speed of the upper disk. Four types of cells were used in the test: C2C12 (mouse myoblast cell line), HUVEC (Human Umbilical Vein Endothelial Cells), 3T3-L1 (mouse fat precursor cells), and L929 (mouse fibroblast connective tissue). After cultivation without flow for 24 hours for adhesion of cells on the lower plate, the shear stress of 1 Pa was continuously applied on cells for 7 days at 310 K. The behavior (alignment and deformation) of each cell was traced at the time lapse image observed by an inverted phase contrast microscope placed in an incubator. The experimental results show the following behavior of each type of cell: C2C12 tends to return to the same direction as that of before division. Deformed 3T3-L1 tends to tilt to the flow direction.
Machine Learning Approach to Predict Sand Transport in Horizontal and Inclined Flow
Authors: Vieira R. E. , Xu B. , Karimi S. , Shirazi S. A. 
Published: October 2021

Abstract
Model predictions are routinely used to help in the decision-making process. For instance, in the oil and gas industry, the accumulation of solid particles, such as sand, and the formation of a bed of solids at the bottom of the pipe can be consequential. Such accumulation may decrease the efficiency of the pipeline due to the increase in the frictional pressure loss; increase the risk of pipeline damage due to erosion; or increase the possibility of pipeline corrosion damage under the bed of solids. In order to transport the solid particles in the pipe, the fluid velocity must exceed the critical velocity required for solid particle transport. Mechanistic models are used to provide a reasonable estimate for the critical velocity needed to transport the particles. However, those models are commonly applicable in their respective ranges of data fitting; and are limited by the applicability of the empirically based closure relations that are a part of such models. On the other hand, the accumulation of experimental data makes possible the application of data-driven methods for characterizing multiphase flow for a broader range of flow conditions. This paper presents a framework to predict the fluid velocity needed to transport solid particles in a pipeline via machine learning (ML) approach. In order to prepare a dataset for training ML models, the critical velocity data are collected from available sources in literature. With the purpose of decreasing the number of input parameters for ML algorithms and to make the model similar for different types of carrying fluids, a set of dimensionless variables has been used. To create the predictive models, three ML algorithms are applied: Random Forest, Support Vector Machine, and Gradient Boosting. The fine-tuned models are compared using statistical analysis to identify the ones that provide the most accurate velocity predictions for different operating conditions. Moreover, the predictive abilities of the models are further validated by comparing their performance with different mechanistic models. The proposed ML approach demonstrates high accuracy in predicting critical velocity across a wide range of flow conditions and inclination angles.
Three-Dimensional Weighted Multiple-Relaxation-Time Pseudopotential Lattice Boltzmann Method for Multiphase Flow
Authors: Tang Jun , Zhang Shengyuan , Wu Huiying 
Published: October 2021

Abstract
The pseudopotential lattice Boltzmann (LB) method has been widely used for simulating multiphase flow due to its concise concept and computational simplicity. In this paper, based on the weighted orthogonal transformation matrix, a three-dimensional (3D) weighted multiple-relaxation-time pseudopotential lattice Boltzmann method (WRMT-LBM) is developed, in which the standard lattice stencil D3Q19 is adopted. Compared with the classical multiple-relaxation-time pseudopotential lattice Boltzmann method (CMRT-LBM) based on the orthogonal transformation matrix, the expressions of the equilibrium density distribution function and discrete force term in moment space are simplified in the present model, which contributes to simplifying the program implementation and improving the computational efficiency. Moreover, an additional discrete source term in moment space compatible with the proposed model is introduced to achieve tunable surface tension. A series of numerical tests are then implemented to investigate the performance of the proposed model. Compared with the CMRT-LBM, the results of the present model can achieve lower spurious velocity and higher computational efficiency while keeping comparable accuracy. Furthermore, using the present model, three benchmark cases, including droplet oscillation, droplet impacting on wall and droplet impact on thin film, are performed to investigate the performance of this model. The numerical results are in good agreement with the analytical solutions or the empirical correlations in the literature, which demonstrates that the present model can simulate the multiphase flow with large density ratio.
Study on Overall Design of a Vertical Take-Off and Landing Unmanned Aerial Vehicle Powered by Electric Ducted Fans
Authors: Chou Tawei , Ying Qiyu , Qian Yuping , Zhuge Weilin , Zhang Yangjun 
Published: October 2021

Abstract
Facing the growing traffic fleet in the cities nowadays, it is believed that three-dimensional urban transportation could be a solution and will be introduced in the near future. Vertical take-off and landing flying platforms powered by ducted fans will attract increasingly attention because it has advantages on high propulsion efficiency, low noise, and better safety. However, unlike traditional open-blade multi-rotor drones, ducted fan drones lack a systematic design approach that comprehensively considers the overall system performance and the power unit efficiency. Current design procedure leads to insufficient load capacity and low efficiency systems. This paper proposes an overall design method for a ducted fan-type vertical take-off and landing flight platform. The ducted fan and motor of the core power unit are designed and selected aiming at improving aerodynamic efficiency and structural utilization of the system. A heavy-load vertical take-off and landing Unmanned Aerial Vehicle (UAV) powered by ducted fans with a take-off weight of 450kg is designed based on this method. CFD simulation is utilized to calculate the performance of the designed Unmanned Aerial Vehicle, and finite element analysis is carried out to examine the overall strength safety. The final design results show that the overall design method plays a great role in the development of ducted fan UAV.
Investigation of Tool-Joint Effect on Non-Newtonian Drilling Fluids Following the Herschel–Bulkley Model Flow Behavior in Oil Well Drilling
Authors: Gholami Ardeshir , Mansoori Zohreh , Saffar Aval Majid , Ahmadi Goodarz 
Published: October 2021

Abstract
The prediction of frictional pressure loss in many oil wells drillings is of the utmost importance. Most studies in this area concerned fluid flow in pipes and annulus in order to predict friction losses. However, studies on the tool-joint effect in frictional pressure estimations were limited to only a few experimental and theoretical studies on water-based power-law drilling muds. (Tool-joint is the part in which two drill strings connect where the annulus has a gradual decrease and increase, respectively). The tool-joint plays an important role in extending the drill pipe, and its effect on pressure losses cannot be ignored. As of today, drilling muds must have certain qualities such as providing formation integrity, transporting the cuttings from bit to surface, drill pipe lubrication and heat transfer, and low-pressure loss to perform as a qualified and effective drilling fluid. Therefore, drilling muds have become more complex and expensive, and the process of choosing appropriate drilling muds is of great importance. For this reason, oil-based viscoplastic drilling muds are being used in more drilling operations, but for these drilling muds, almost no studies were conducted to predict the effect of the tool-joints on flow behavior and pressure loss.
In this paper, the behavior of fluid flows and frictional pressure losses in weld-on tool-joints of different grades according to the IADC standard manual was studied using CFD simulations. The simulations were conducted using a drilling fluid with viscoplastic properties, following the Herschel–Bulkley model of Non-Newtonian fluids. And the characteristics of fluid flows in these tool-joints under different thermal boundary conditions were studied. The results show that tool-joints significantly affect the frictional pressure loss in the annulus. We also provided an accurate pressure loss prediction for the flow of oil-based viscoplastic muds passing through the tool-joint geometry. Furthermore, assuming the thixotropic behavior using the Moore-Cheng model for the drilling mud, the results showed that the flow behavior does not differ significantly from the Herschel-Bulkley drilling fluid in the range of study.