bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of different parameters related to milling tools to maximize the allowable cutting depth for chatter-free machining
Authors: Mokhtari Ali , Jalili Mohammad Mahdi , Mazidi Abbas
Published: July 2020

Determination of optimal parameters of cutting tool is one of the most significant factors in any operation planning of metal elements, especially in micro-milling process. This article presents an optimization procedure, based on genetic algorithms, to optimize some parameters related to micro-milling tool including number of teeth, shank diameter, fluted section diameter, shank length, taper length, and length of fluted section. The aim of this optimization is maximizing the minimum value of cutting depth on the border of stability lobe diagrams, which is called allowable cutting depth, for chatter-free machining. Cutting tool is modeled as a three-dimensional spinning cantilever Timoshenko beam based on strain gradient elasticity theory. Structural nonlinearity, gyroscopic moment, rotary inertia, and velocity-dependent process damping are also considered in the cutting tool model. The values of natural frequency, damping ratio, and material length scale of the micro-milling tool are calculated using a system identification based on genetic algorithm to match the analytical response with recorded experimental vibration signal. Using beam model, the allowable cutting depth is increased in the optimization process for a specific range of spindle speed to avoid the chatter phenomenon. Analytical study of micro-milling process stability is carried out to determine the cost function of the genetic algorithm. A plot of the greatest fitness in each generation is sketched. In addition, stability lobe diagrams before and after optimization process are presented to show the efficiency of the optimized micro-milling tool. In the presented examples, the results of genetic algorithm may lead to design or find a micro-milling tool that its acceptable cutting depth increases up to 1.9313 times.
Investigating the relation between debinding atmosphere and mechanical properties of stereolithography-based three-dimensional printed Al2O3 ceramic
Authors: Li He , Liu Yongsheng , Liu Yansong , Hu Kehui , Lu Zhigang , Liang Jingjing
Published: July 2020

Ceramic green bodies fabricated by stereolithography-based three-dimensional printing technology often have high loading of ultraviolet curable resins, which produce undesirable phenomena such as cracking, deformation, and blistering during the debinding process. Results showed that compared to argon and vacuum, air atmosphere provided higher flexural strength owing to the elevated density. The differences in microstructure between specimens prepared under these atmospheres were attributed to exothermic oxidation reactions occurred under air when compared to endothermic pyrolysis reactions under vacuum and argon. The debinding atmosphere showed little effect on crystallite size due to the elevated sintering temperature, which would determine the final crystallite size of Al2O3. Debinding under air atmosphere resulted in flexural strength of 176.69 MPa and open porosity of 23.4%. The flexural strength of the ceramics debinded in air was 21.6% higher than the ceramics debinded in argon atmosphere.
Comparison of arterial wave intensity analysis by pressure–velocity and diameter–velocity methods in a virtual population of adult subjects
Authors: Reavette Ryan M , Sherwin Spencer J , Tang Mengxing , Weinberg Peter D
Published: July 2020

Pressure–velocity-based analysis of arterial wave intensity gives clinically relevant information about the performance of the heart and vessels, but its utility is limited because accurate pressure measurements can only be obtained invasively. Diameter–velocity-based wave intensity can be obtained noninvasively using ultrasound; however, due to the nonlinear relationship between blood pressure and arterial diameter, the two wave intensities might give disparate clinical indications. To test the magnitude of the disagreement, we have generated an age-stratified virtual population to investigate how the two dominant nonlinearities, viscoelasticity and strain-stiffening, cause the two formulations to differ. We found strong agreement between the pressure–velocity and diameter–velocity methods, particularly for the systolic wave energy, the ratio between systolic and diastolic wave heights, and older subjects. The results are promising regarding the introduction of noninvasive wave intensities in the clinic.
Non-ischemic endocardial scar geometric remodeling toward topological machine learning
Authors: Singh Yashbir , Shakyawar Deepa , Hu Weichih
Published: July 2020

Scar tissues have been important factors in determining the progression of myocardial diseases and the development of adverse cardiac failure outcomes. Accurate segmentation of the scar tissues can be helpful to the clinicians for risk prediction and better evaluation of cardiovascular diseases. Our goal is to apply topology data analysis toward machine learning algorithms to confirm the geometry of scar tissue, in addition to gaining better visualization and quantification of the scar tissue present. We have introduced architecture for integrating geometry in the form of topology toward machine learning. Morphological image processing was carried out to define the regions of the endocardial wall. We implemented convolutional neural networks on delayed enhancement cardiac computed tomography images for the recognition of scar tissue. Segmented two-dimensional images were stacked up to build the geometry of the scar area for visualization purposes. Mathematical calculations were executed for the validation of the scar tissue in addition to performing morphological image processing and marking the scar tissue present on the endocardial wall of the left ventricular. We applied convolutional neural network over convolution and pooling the layers with small sizes; we achieved 89.23% accuracy, 91.11% sensitivity, and 87.75% specificity, and found the dissimilarity distance between the normal endocardial tissue distances to be 9.37. This new concept in this study contributes toward a better understanding of scar structure and transmural variation of the endocardial wall of the left ventricular.
Hemodynamic performance of a compact centrifugal left ventricular assist device with fully magnetic levitation under pulsatile operation: An in vitro study
Authors: Wu Tingting , Lin Hao , Zhu Yuxin , Huang Penghui , Lin Frank , Chen Chen , Hsu Po-Lin
Published: July 2020

Long-term using continuous flow ventricular assist devices could trigger complications associated with diminished pulsatility, such as valve insufficiency and gastrointestinal bleeding. One feasible solution is to produce pulsatile flow assist with speed regulation in continuous flow ventricular assist devices. A third-generation blood pump with pulsatile operation control algorithm was first characterized alone under pulsatile mode at various speeds, amplitudes, and waveforms. The pump was then incorporated in a Mock circulation system to evaluate in vitro hemodynamic effects when using continuous and different pulsatile operations. Pulsatility was evaluated by surplus hemodynamic energy. Results showed that pulsatile operations provided sufficient hemodynamic assistance and increased pulsatility of the circulatory system (53% increment), the mean aortic pressure (65% increment), and cardiac output (27% increment). The pulsatility of the system under pulsatile operation support was increased 147% compared with continuous operation support. The hemodynamic performance of pulsatile operations is susceptible to phase shifts, which could be a tacking angle for physiological control optimization. This study found third-generation blood pumps using different pulsatile operations for ventricular assistance promising.
Design and validation of a foot–ankle dynamic simulator with a 6-degree-of-freedom parallel mechanism
Authors: Wang Dongmei , Wang Wei , Guo Qinyang , Shi Guanglin , Zhu Genrui , Wang Xu , Liu Anmin
Published: July 2020

An in vitro simulation test using a designed well-targeted test rig has been regarded as an effective way to understand the kinematics and dynamics of the foot and ankle complex in the dynamic stance phase, and it also allows alterations in both internal and external control compared to in vivo tests. However, current simulators are limited by some assumptions. In this study, a novel foot and ankle bionic dynamic simulator was developed and validated. A movable 6-degree-of-freedom parallel mechanism, known as Steward platform, was used as the core structure to drive the tibia, with a tibial force actuator applied with different loads. Four major muscle groups were actuated by four sensored pulling cables connected to muscle tendons. Simulation processes were controlled using a software developed based on a proportional–integral–derivative control loop, with tension–compression sensors mounted on tendon pulling cables and used as real-time monitor signals. An iterative learning module for tibial force control was integrated into the control software. Six specimens of the cadaveric foot–ankle were used to validate the simulator. The stance phase was successfully simulated within 5 s, and the tibia loads were applied based on the body weight of the cadaveric specimen donors. Typical three-dimensional ground reaction forces were successfully reproduced. The coefficient of multiple correlation analysis demonstrated good repeatability of the dynamic simulator for the ground reaction force (coefficient of multiple correlation > 0.89) and the range of ankle motion (coefficient of multiple correlation > 0.87 with only one exception). The simulated ranges of the foot–ankle joint rotation in stance were consistent with in vivo measurements, indicating the success of the dynamic simulation process. The proposed dynamic simulator can enhance the understanding of the mechanism of the foot–ankle movement, related injury prevention, and surgical intervention.
Fixation of distal tibia fracture through plating, nailing, and nailing with Poller screws: A comparative biomechanical-based experimental and numerical investigation
Authors: Baseri Amin , Bagheri Mohammad Ali , Rouhi Gholamreza , Aghighi Mohammad Reza , Bagheri Nima
Published: July 2020

The goal of this study was to investigate two commonly used methods of fixation of distal metaphyseal tibia fractures, plating and nailing as well as the less frequently employed nailing with Poller screws, from a biomechanical perspective. Despite numerous studies, the best method to repair fractures of tibia the remains up for of debate. This study includes an in vitro experimental phase on human cadaveric tibias followed by a finite element analysis. In the experimental phase, under partial weight-bearing axial loading, the axial stiffness of the bone-implant construct and interfragmentary movements for each of the fixation methods, bone-plate, bone-nail, and bone-nail-Poller screw, were measured and compared with each other. Shear interfragmentary movement and stress distribution in the bone-implant construct for the three mentioned fixation methods were also determined from FE models and compared with each other. Results of in vitro experiments, i.e., the exertion of axial loading on the tibia-plate, tibia-nail, and tibia-nail-Poller screw, showed that utilization of tibia-nail and tibia-nail-Poller screw led to a stiffer bone-implant construct, and consequently, lower interfragmentary movement, compared to the tibia-plate construct ( p values for tibia-nail and tibia-nail-Poller screw, and for both axial stiffness and interfragmentary movement, compared to those of tibia-plate construct, were less than 0.05). Numerical analyses showed that nailing produced less undesirable shear interfragmentary movement, compared to the plating, and application of a Poller screw decreased the shear movements, compared to tibia-nail. Furthermore, using the finite element analysis, maximum von Mises stress of adding a screw in tibia-nail, tibia-plate, and tibia-nail-Poller screw, was found to be: 51.5, 78.6, and 60.5 MPa, respectively. The results of this study suggested that from a biomechanical standpoint, nailing both with and without a Poller screw is superior to plating for the treatment of distal tibia fractures.
Design and implementation of a hybrid control for the energy management system in electric traction
Authors: Bejaoui Fatah , Mechmeche Chokri , Tlili Ali Sghaier , Yahoui Hamed
Published: July 2020

This article intends designing and implementing a hysteresis current controller for the energy management system within an electric traction to maintain the output voltage in a certain interval whatever the disturbances to the system. The energy management system within an electric traction encompasses a battery functioning as a fuel cell within the primary energy source, an ultracapacitor considered as an auxiliary source and two direct current to direct current converters renowned as boost and buck/boost converters, whose modeling is constantly contemplated as a very difficult task. As a matter of fact, these converters are designed as switching circuits with a prevalent change of structures, which makes them strongly nonlinear. Thereby, they can be assumed as hybrid dynamical systems whose continuous parts are especially characterized by electrical magnitudes, namely, the currents and voltages in the converters, and whose discrete part is illustrated by the high-frequency switching metal–oxide–semiconductor field-effect transistor which demands faster control mechanisms to ensure proper regulation of the output voltage of two direct current to direct current converters. The validity and effectiveness strategy control of the energy management system are highlighted by numerical simulation as well as by experimental implementation on the DSPACE1104 R&D Controller Board.
Motion control of a cable-suspended robot using image recognition with coordinate transformation
Authors: Lin Jonqlan , Chiang Cheng-Kai
Published: July 2020

This study will concern the implementation of a vision-based controller for cable-suspended robots, and especially for the pick-and-place function. This work will develop a novel algorithm that combines cable-suspended robot coordinate transformation with image recognition to manipulate the suspended gripper to the desired position for material-handling tasks. Two webcams sense the position of the end-effector; one will be used to calculate the horizontal planar coordinate of the target, and the other will be used to determine the vertical height of the target. Accordingly, the two-dimensional spatial image can be converted into three-dimensional image coordinates. Based on the sensed information, the robot can convert the position of the target to required cable lengths and then drive the servomotor to retract (or release) the cables to move the suspended gripper to the desired position. Various experiments will be conducted to verify the proposed methodology. The framework that is developed herein is easily implemented for real-time control and is suitable for inclusion in mechatronic kits in a university control course. The large variety of ideas that are addressed in this work apply to cranes, aerostats, and other large-scale manufacturing equipment that requires cable-driven robots.
Fault diagnosis based on deep learning by extracting inherent common feature of multi-source heterogeneous data
Authors: Zhou Funa , Yang Shuai , He Yifan , Chen Danmin , Wen Chenglin
Published: July 2020

Fault diagnosis can provide a basic guarantee for safe operation of industrial equipment. Deep learning has attracted much attention from experts in the field of fault diagnosis because of its powerful feature representation ability. But traditional deep learning methods cannot well extract common feature from multi-source heterogeneous data which is the inherent character of the monitored object. Using only one kind of heterogeneous data for deep learning fault diagnosis will inevitably result in poor diagnosis accuracy. Aiming at this problem, this article proposes a deep common feature extraction method by designing a fusion network with alternating optimization mechanism. The rough features extracted independently from two kinds of heterogeneous data are used to train the designed fusion network in an alternative optimization way. A new loss function required by alternative optimization is established; thus, all the networks can be tuned globally. The deep common features of multi-source heterogeneous data can be well extracted by alternating optimization training process of the fusion network, which improves the accuracy of deep learning fault diagnosis method. Experiments for rolling bearings fault diagnosis testify the effectiveness of the proposed algorithm.
Fire, humans and climate as drivers of environmental change on Broughton Island, New South Wales, Australia
Authors: Mooney Scott D. , Hope Geoffrey , Horne Dylan , Kamminga Johan , Williams Alan N.
Published: July 2020

In Australia, the drivers of precolonial fire regimes remain contentious, with some advocating an anthropogenic-dominated regime, and others highlighting the importance of climate, climatic variability or alternatively some nexus between climate and human activity. Here, we explore the inter-relationships between fire, humans and vegetation using macroscopic charcoal, archaeology and palynology over the last ~5430 cal. year BP from Broughton Island, a small, near-shore island located in eastern Australia. We find a clear link between fire and the reduction of arboreal pollen and rainforest indicators on the island, especially at ~4.0 ka and in the last ~1000 years. Similarities with comparable palaeoenvironmental records of fire in the region and a record of strong El Niño (dry, fire-prone) events supports the contention that climate was a significant influence on the fire regimes of Broughton Island. However, two periods of enhanced fire activity, at ~4000 years BP and ~<600 years BP have weaker links to climate, and perhaps reflect anthropogenic activity. Changes to the fire regime in the last ~600 years corresponds with the earliest evidence of Indigenous archaeology on the island, and coincides with implications that Polynesian people were present in the region. After the mid-Twentieth Century a human-dominated fire regime is also an obvious feature of the reconstructed fire record on Broughton Island.
Vegetation response to wildfire and climate forcing in a Rocky Mountain lodgepole pine forest over the past 2500 years
Authors: Chileen Barrie V , McLauchlan Kendra K , Higuera Philip E , Parish Meredith , Shuman Bryan N
Published: July 2020

Wildfire is a ubiquitous disturbance agent in subalpine forests in western North America. Lodgepole pine ( Pinus contorta var. latifolia), a dominant tree species in these forests, is largely resilient to high-severity fires, but this resilience may be compromised under future scenarios of altered climate and fire activity. We investigated fire occurrence and post-fire vegetation change in a lodgepole pine forest over the past 2500 years to understand ecosystem responses to variability in wildfire and climate. We reconstructed vegetation composition from pollen preserved in a sediment core from Chickaree Lake, Colorado, USA (1.5-ha lake), in Rocky Mountain National Park, and compared vegetation change to an existing fire history record. Pollen samples ( n = 52) were analyzed to characterize millennial-scale and short-term (decadal-scale) changes in vegetation associated with multiple high-severity fire events. Pollen assemblages were dominated by Pinus throughout the record, reflecting the persistence of lodgepole pine. Wildfires resulted in significant declines in Pinus pollen percentages, but pollen assemblages returned to pre-fire conditions after 18 fire events, within c.75 years. The primary broad-scale change was an increase in Picea, Artemisia, Rosaceae, and Arceuthobium pollen types, around 1155 calibrated years before present. The timing of this change is coincident with changes in regional pollen records, and a shift toward wetter winter conditions identified from regional paleoclimate records. Our results indicate the overall stability of vegetation in Rocky Mountain lodgepole pine forests during climate changes and repeated high-severity fires. Contemporary deviations from this pattern of resilience could indicate future recovery challenges in these ecosystems.
From doubt to trust: Swedish mothers’ and counsellors’ experience testing a parenting programme for mothers exposed to intimate partner violence whose children have developed behavioural problems
Authors: Draxler Helena , McDonald Renée , Hjärthag Fredrik , Almqvist Kjerstin
Published: July 2020

Many countries seek evidence-based interventions for children who have been exposed to domestic violence, and they frequently turn to interventions developed in the US and disseminated to Europe as a solution. Societal and cultural differences may, however, pose barriers to successful implementation. Project Support (PS), piloted in this study through social services agencies in Sweden, has shown positive effects in the US for families with children who have been exposed to intimate partner violence (IPV). The aim of this study was to investigate counselors’ and caregivers’ experiences when giving/receiving PS in Sweden.

The study was based on interviews conducted with 11 mothers and 13 counselors with experience in the programme. A thematic analysis showed three themes (Initial doubts, Confidence from positive change, and Flexibility- challenge for the organization) and the study adds information about obstacles for implementation of PS in Sweden. Cultural and organizational differences between Sweden and the US in practice and child-rearing attitudes are highlighted, as well as the importance of making adjustments while maintaining treatment fidelity, and promoting the dissemination of the approach.
The strong column–weak beam design philosophy in reinforced concrete frame structures: A literature review
Authors: Nie Xuefei , Zhang Shishun , Jiang Tao , Yu Tao
Published: July 2020

This article presents a literature review of existing research on the strong column–weak beam design philosophy, which has been widely adopted in the seismic design of frame structures. A comprehensive review of this design philosophy, including its concept and research history, especially factors affecting the accurate calculation of the flexural capacity of beams [Formula: see text] and the determination of the column-to-beam flexural strength ratio [Formula: see text], is presented first. The development of design provisions of four representative countries for this design philosophy is also reviewed. The implementation of strong column–weak beam hierarchy in real structural design is then discussed, and existing problems are pointed out. Finally, different techniques for the seismic retrofit of existing reinforced concrete frames are reviewed.
Experimental investigation on the effect of injector hole number on engine performance and particle number emissions in a light-duty diesel engine
Authors: Mohiuddin Khawar , Kwon Heesun , Choi Minhoo , Park Sungwook
Published: July 2020

Particle number emissions need to be monitored and controlled in order to comply with the latest emission legislations for gasoline and diesel engines. This research focuses on performance and emission analysis of a light-duty diesel engine with various injector hole numbers. A 500cc single-cylinder diesel engine was used for this purpose, and injectors with hole numbers varying from 7 to 10 were analyzed. Different operating conditions were selected to test the engine at all types of loading conditions. Start of injection and exhaust gas recirculation swings were carried out at all the test cases to see the variation of particle number and other emissions. Increasing injector hole number from 7 to 9, in-cylinder pressure heat release rate and combustion duration increased while ignition delay was shortened. Soot-NOx and ISFC-NOx trade-offs also improved with decreasing hole diameter for these hole numbers. Particle number emissions reduced significantly with increasing hole number. However, the 10-hole injector exhibited a different behavior than the other injectors. For low loading case, cylinder pressure and heat release rate were higher than those of the 9-hole injector but for medium and high loading cases, in-cylinder pressure, heat release rate, and combustion duration of the 10-hole injector were found to be lesser than the 9-hole injector. For medium and high loading cases, particle number emissions from the 10-hole nozzle also increased as compared to the 9-hole injector. Optical engine investigation revealed a higher flame-flame interference in case of the 10-hole injector which resulted in degraded combustion performance and higher particle number emissions.
On the functional model–based method for vibration-based robust damage detection: versions and experimental assessment
Authors: Aravanis Tryfon-Chrysovalantis , Sakellariou John , Fassois Spilios
Published: July 2020

The problem of random vibration–based robust damage detection for structures operating under varying and non-measurable environmental and operating conditions is considered via a novel unsupervised functional model–based method. Two versions of the method are employed based on either the residual variance or uncorrelatedness (whiteness) of a proper functional model that incorporates the varying environmental and operating conditions in a scheduling vector. This article constitutes a proof-of-concept study in which a comprehensive laboratory assessment of the functional model–based method is undertaken using hundreds of experiments with a composite tail structure of an unmanned aerial vehicle and two early-stage damages under a considerable number of different environmental and operating conditions. Comparisons with two alternative state-of-the-art statistical time series type methods, that is, a multiple model–based method and a principal component analysis–based method, are also performed. The results indicate ideal detection performance for the functional model–based and multiple model–based methods, with the true positive rate reaching 100% at 0% false positive rate, but degraded performance for the pricipal component analysis–based method.
Mechanism of the effect of temperature on frequency based on long-term monitoring of an arch bridge
Authors: Teng Jun , Tang De-Hui , Hu Wei-Hua , Lu Wei , Feng Zhi-Wen , Ao Chun-Feng , Liao Ming-Hao
Published: July 2020

In this study, the mechanism of the effect of temperature on structural frequency is investigated by integrating correlation analysis, numerical simulation, and neural network techniques. First, the different spatial–temporal influence patterns of the temperature field on frequency are observed using correlation analysis based on the long-term monitoring of an arch bridge. Subsequently, a numerical simulation is performed to quantitatively analyze the effect of temperature on frequency in terms of internal force, geometric size, elastic modulus, and boundary condition. It is observed that an unknown factor—except for the elastic modulus—leads to variation in the frequency of the beam mode. The spatial effect of the temperature field is separated by a genetic-algorithm-optimized backpropagation neural network. It is inferred that the frequency of the beam mode is influenced in terms of the boundary condition and the elastic modulus because of temperature, whereas the frequency of the arch mode is only influenced by the changing elastic modulus.
Automated wireless monitoring system for cable tension forces using deep learning
Authors: Jeong Seunghoo , Kim Hyunjun , Lee Junhwa , Sim Sung-Han
Published: July 2020

As demand for long-span bridges is increasing worldwide, effective maintenance has become a critical issue to maintain their structural integrity and prolong their lifetime. Given that a stay-cable is the principal load-carrying component in cable-stayed bridges, monitoring tension forces in stay-cables provides critical data regarding the structural condition of bridges. Indeed, various methodologies have been proposed to measure cable tension forces, including the magneto-elastic effect-based sensor technique, direct measurement using load cells, and indirect tension estimation based on cable vibration. In particular, vibration-based tension estimation has been widely applied to systems for tension monitoring and is known as a cost-effective approach. However, full automation under different cable tension forces has not been reported in the literature thus far. This study proposes an automated cable tension monitoring system using deep learning and wireless smart sensors that enables tension forces to be estimated. A fully automated peak-picking algorithm tailored to cable vibration is developed using a region-based convolution neural network to apply the vibration-based tension estimation method to automated cable tension monitoring. The developed system features embedded processing on wireless smart sensors, which includes data acquisition, power spectral density calculation, peak-picking, post-processing for peak-selection, and tension estimation. A series of laboratory and field tests are conducted on a cable to validate the performance of the proposed automated monitoring system.
Third harmonic shear horizontal waves for material degradation monitoring
Authors: Wen Fuzhen , Shan Shengbo , Cheng Li
Published: July 2020

Early detection of incipient damage in structures through material degradation monitoring is a challenging and important topic. Nonlinear guided waves, through their interaction with material micro-defects, allow possible detection of structural damage at its early stage of initiations. This issue is investigated using both the second harmonic Lamb waves and the third harmonic shear horizontal waves in this article. A brief analysis first highlights the selection of the primary–secondary S0 Lamb wave mode pair and primary–tertiary SH0 mode pair from the perspective of cumulative high-order harmonic wave generation. Through a tactic design, an experiment is then conducted to compare the sensitivity of the third harmonic shear horizontal waves and the second harmonic Lamb waves to microstructural changes on the same plate subjected to a dedicated thermal heating treatment. The third harmonic shear horizontal waves are finally applied to monitor the microstructural changes and material degradation in a plate subjected to a thermal aging sequence, cross-checked by Vickers hardness tests. The experiment results demonstrate that the third harmonic shear horizontal waves indeed exhibit higher sensitivity to microstructural changes than the commonly used second harmonic Lamb waves. In addition, results demonstrate that the designed third harmonic shear horizontal wave–based system entails effective characterization of thermal aging–induced microstructural changes in metallic plates.
Commentary: Michael Hand’s ‘on the necessity of school punishment’
Authors: Goodman Joan
Published: July 2020

Michael Hand maintains that punishment is necessary for school children to insure compliance with the important rules – those he calls moral and scholastic. I make three arguments against this position: First, Hand fails to separate the sorts of behaviors legitimately classified as interfering with teaching and learning from more trivial rules, leaving that determination entirely to the discretion of teachers. While Hand acknowledges a teacher must exercise ‘fine-grained judgement’ in determining the rules, fine-grained can easily become arbitrary; a subjective exercise that transforms a teacher’s preferred practice into a scholastic must-be-obeyed punishable offense. Second, Hand also fails to clarify which, among the vast array of sanctions teachers impose upon students, are to be included in the category of punishment. How is punishment cordoned off from corrections, penalties, and discipline? Third, in assuming that without punishment self-interest (selfishness) will prevail over unselfishness, and that punishment supports moral formation (consideration of others), Hand oversimplifies the complex motives that shape behavior.
Stability of an electrified liquid jet approaching to critical point
Authors: Fang Zixuan , Wang Ping
Published: July 2020

This article reports the linear stability analysis of a thermodynamic-transcritical jet sprayed to a radial electrical field. An asymptotic approach was used to obtain the stability solution of a supercritical jet subjected to electrical field. In order to obtain the solutions for the electrified supercritical jet, the surface tension was decreased and consequently led the increase in Weber number in the linear governing equation of subcritical charged jet. To investigate the role of surface tension and electric stress playing in the destabilizing process when approaching the critical point, the energy budget is performed by tracing the energy sources. It was found that, when the Weber number is increased to a sufficiently large value, the solution will become an asymptotic value, which can be considered as a solution under the supercritical conditions. The electric stress can increase both the maximum growth rate and the dominant wave number of electrified supercritical jet, that is, higher electrical field intensity would enhance the instability of the electrified supercritical jet and decrease the wavelength of the disturbances.
Quadrature Kalman filter–based state of charge estimation for lithium-ion battery
Authors: Huang Mengtao , Wang Chao , Liu Bao , Wang Fan , Wang Jingting
Published: July 2020

This article presents an approach to lithium-ion battery state of charge estimation based on the quadrature Kalman filter. Among the existing state of charge estimation approaches, the extended Kalman filter–based state of charge and unscented filter–based state of charge algorithms are influenced by the linearization or the solution of sigma points. The proposed quadrature Kalman filter–based state of charge algorithm avoids these problems. Specifically, the battery system equations are built based on the second-order resistance–capacitance equivalent circuit model, and the parameters are identified according to the hybrid pulse power characterization discharging test. Then, the quadrature points and corresponding weights are defined by the Gauss–Hermite quadrature rule, and the Kronecker tensor product is adopted to solve the points of multivariate. In addition, the stability of quadrature Kalman filter–based state of charge is verified. Finally, the simulation is carried out under the discharging and urban dynamometer driving schedule condition, which demonstrates that the quadrature Kalman filter–based state of charge algorithm has a better performance compared with extended Kalman filter–based state of charge and unscented filter–based state of charge.
Double-blinding of an acupuncture randomized controlled trial optimized with clinical translational science award resources
Authors: Steffen Alana D , Burke Larisa A , Pauls Heather A , Suarez Marie L , Yao Yingwei , Kobak William H , Takayama Miho , Yajima Hiroyoshi , Kaptchuk Ted J , Takakura Nobuari , Wilkie Diana J , Schlaeger Judith M
Published: July 2020

Background

Clinical trial articles often lack detailed descriptions of the methods used to randomize participants, conceal allocation, and blind subjects and investigators to group assignment. We describe our systematic approach to implement and measure blinding success in a double-blind phase 2 randomized controlled trial testing the efficacy of acupuncture for the treatment of vulvodynia.

Methods

Randomization stratified by vulvodynia subtype is managed by Research Electronic Data Capture software’s randomization module adapted to achieve complete masking of group allocation. Subject and acupuncturist blinding assessments are conducted multiple times to identify possible correlates of unblinding.

Results

At present, 48 subjects have been randomized and completed the protocol resulting in 87 subject and 206 acupuncturist blinding assessments.

Discussion

Our approach to blinding and blinding assessment has the potential to improve our understanding of unblinding over time in the presence of possible clinical improvement.
Pernio as the clinical presentation of celiac disease: A case report
Authors: Lemieux Alexandre , Sanchez Vivas Natasha Emily , Powell Julie , Jantchou Prévost , Morin Marie-Paule
Published: July 2020

We present the case of a 12-year-old girl with severe pernio as the sole clinical presentation of celiac disease (CD), without associated gastrointestinal symptoms. Lesions greatly improved once a gluten free diet was initiated. At 5-year follow-up, she remains in clinical remission throughout the year with no pharmacological treatment, without skin lesions flare-up in the winter months.
Innocuous wound with occult central vascular injury: A case report
Authors: Kumar Abhinav , Choudhary Narendra , Ghoshal Soumya , Agarwal Harshit
Published: July 2020

Penetrating trauma is one of the most common cause of occult vascular injury, especially in low velocity penetrating injury. This is usually in pretext of an innocuous looking small external wound. It is important for clinician to have high index of suspicion for such types of injuries, as the clinical examination with presenting signs and symptoms may be deceptive. Radiological evaluation is of paramount importance and essential to rule out any occult vascular insult. Conventional open surgical exploration is the gold standard for vascular injuries in neck. Minimal invasive endovascular stenting has selective role based on zone of neck, mechanism of injury, hemodynamic stability, neurological status and resource availability at treating centre. Early diagnosis and referral to an appropriate higher centre, preferably a trauma centre with expertise in handling major vascular injuries, improve the outcome. We present a case report of small innocuous looking external wound harbouring major central vessel injury underneath following low-velocity penetrating injury.
No significant relation of proinflammatory slanDCs with uremic pruritus
Authors: Ulrich Christof , Leonhardt Anja , Trojanowicz Bogusz , Seibert Eric , Fiedler Roman , Girndt Matthias
Published: July 2020

The pathogenesis of the pruritus associated with chronic kidney disease-(CKD-aP) is not completely understood. Endocrine, metabolic, neuropathic, and inflammatory disorders were suspected to be the origin of CKD-aP. Based on the hypothesis which suggests that deregulated systemic inflammation may play a crucial role in CKD-a, we investigated the potential relation of an inflammatory monocyte subset (slanDCs) with CKD-aP. Itch questionnaire, visual analogue scale (VAS)-scoring, and Dermatology Life Quality Index (DQLI) were applied for the characterization of itch sensation. VAS-scoring was re-evaluated after 6 months. Monocytes were flow-cytometrically categorized into classical, intermediate, and non-classical subsets. slanDCs are part of the non-classical monocyte subpopulation. Sixty-six hemodialysis patients (CKD5-D) were screened of whom 43 met the study inclusion criteria. In all, 46.5% of patients were scored pruritus-positive (CKD-aP+). CKD-aP severity level of patients was moderate at the start of the study (VAS 5.3 ± 2.5) and remained unchanged after 6 months (VAS: 5.2 ± 1.9, P < 0.757). Thirty percent of patients were affected with mild, 30.0% with moderate, and 35.0% with severe itchiness. In contrast to all other factors tested solely slanDC showed a weak correlation to VAS-score (r = 0.41, P = 0.07). slanDC frequencies between CKD5-D patients with and without itch sensation, however, were not significantly different. Endocrine problems appeared to influence CKD-aP. CKD-aP + patients had significantly higher L-thyroxin supplementation than CKD-aP- (50.0% vs 8.7%, P < 0.005). A binary logistic regression model confirmed the significance of L-thyroxin medication on chronic itch problems of our CKD5-D patients ( P < 0.007). There is no clear evidence that slanDCs are related to uremic pruritus. Therefore, other factors underlie the pathophysiology of CKD-aP.
Anti-inflammatory effects of rosuvastatin treatment on coronary artery ectasia patients of different age groups
Authors: Fan Cheng-Hui , Hao Ying , Liu Yong-Hua , Li Xiao-Lin , Huang Zhen-Hao , Luo Yu , Li Rui-Lin
Published: July 2020

Background

Coronary artery ectasia (CAE) is an angiographic finding of abnormal coronary dilatation. Inflammation plays a major role in all phases of atherosclerosis. We investigated the relationship between CAE and serum high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) levels to test our hypothesis that patient age is associated with the efficacy of anti-inflammatory therapy for CAE.

Methods

We conducted a prospective analysis of 217 patients with CAE treated at the Department of Cardiology, Shanghai East Hospital, Ji’an Campus and the Baoshan People’s Hospital, from January 1, 2015 to July 30, 2019. Baseline data of patients, including sex; age; and history of hypertension, hyperlipidemia, and diabetes, were collected from patient medical records. Study participants were grouped by age as follows: CAE-A (n = 60, age ≤ 50 years), CAE-B (n = 83, 50 years  70). Additionally, there was a control (NC) group (n = 73) with normal coronary arteries.

Results

All patients received oral rosuvastatin therapy (10 mg, QN quaque nocte) when they were diagnosed with CAE and maintained good follow-up, with a loss rate of 0.0% at the end of the 6-month follow-up. The NC group received regular symptom-relieving treatments and rosuvastatin therapy. Of these four groups, the inflammatory markers, hs-CRP and IL-6, were significantly higher in patients with CAE than in the NCs (p < 0.05). Post-hoc tests showed that hs-CRP and Il-6 levels had significant differences between the CAE-A and CAE-C groups (P = 0.048, P = 0.025). Logistic regression analysis showed that hs-CRP (OR = 1.782, 95% CI: 1.124–2.014, P = 0.021) and IL-6 (OR = 1.584, 95% CI: 1.112–1.986, P = 0.030) were independent predictors of CAE. The inflammatory markers were higher in the CAE-A group than in the CAE-B group and higher in the CAE-B group than in the CAE-C group. Follow-up after 6 months of rosuvastatin therapy showed a significantly greater reduction in hs-CRP and IL-6 levels in the CAE-A group than in the CAE-B group, which again were greater in the CAE-B group than in the CAE-C group.

Conclusions

Anti-inflammatory therapy using rosuvastatin was more effective in younger CAE patients, indicating the need for early statin therapy in CAE.
When a viral eruption hides another one: intrafamilial outbreak of parvovirus B19 and measles virus co-infections: case report
Authors: Grolhier Claire , Pronier Charlotte , Belem Arielle , Dina Julia , Vabret Astrid , Grau José-Hector Aranda , Tattevin Pierre , Thibault Vincent
Published: July 2020

Background

Despite high overall population vaccine coverage, identified clusters of persons refraining from vaccination interfere with pursued measles elimination. Clinical diagnosis of measles is often obvious due to its typical rash. Yet, febrile rashes may occur during many viral infections. Misdiagnosis of a specific primary viral infection may have severe consequences, particularly in immunocompromised subjects or pregnant women. To our knowledge, this case presentation is the first description of a measles and parvovirus B19 coinfection outbreak. Analysis of this outbreak underlines rash diagnosis difficulties and potential serology interpretation pitfalls. This case report is helpful for the clinicians in the context of measles re-emergence and proposes several methods to improve the diagnosis approach.

Case presentation

We investigated an outbreak of rash in 6 out of 8 Traveler family members presenting to Rennes University Hospital (West of France). Anti-B19V and measles IgM/IgG antibodies were measured and detection of Parvovirus B19 and measles virus genomes were done on blood and/or respiratory samples. Virological investigations finally documented 6 cases of parvovirus B19 infections, including 4 associated with measles. Interestingly, in the four coinfection cases, the rash was typical of B19V primary infection for the two children but typical of measles for the two adults. Clinical diagnosis of rash may be misleading and thorough virological investigations may be required to avoid misdiagnosis.

Conclusions

This investigation first reports an intra-familial outbreak of MeV/B19V coinfections highlighting the high transmissibility of both viruses and the diagnostic challenges of dual rash-associated infections. This report also underlines the potential deleterious consequences of failure to identify measles cases, especially in a community with low vaccination coverage.
Recurrent pneumonia in a patient with new coronavirus infection after discharge from hospital for insufficient antibody production: a case report
Authors: Zhou Xiaoxi , Zhou Jianfeng , Zhao Jianping
Published: July 2020

Background

The rapid spread of coronavirus disease 2019 (COVID-19) was declared as an emerging public health threat by the World Health Organization. As various measures have been taken successfully to combat the epidemic caused by SARS-CoV-2, a growing number of fully recovered patients have been discharged from hospitals. However, some of them have relapsed. Little is known about the causes that triggered the relapse.

Case presentation

We report a case of a 40 years old man who suffered from recurrent pulmonary infection with progression of lesions on chest computed tomography (CT), elevated levels of ferritin and IL2R, reduced lymphocyte count and positive oropharyngeal swab test for SARS-CoV-2 again after 5 days discharge from hospital. The anti-SARS-CoV-2 antibody level of this patient was very low at the time of relapse, suggesting a weak humoral immune response to the virus. Total exon sequencing revealed mutations in TRNT1 gene, which may be responsible for B cell immunodeficiency. Therefore, uncleared SARS-CoV-2 at his first discharge was likely to lead to his recurrence. However, viral superinfection and non-infectious organizing pneumonia could not be completely excluded.

Conclusion

COVID-19 relapse may occur in a part of discharged patients with low titers of anti-SARS-CoV-2 antibodies. These patients should be maintained in isolation for longer time even after discharge. A more sensitive method to detect SARS-CoV-2 needs to be established and serological testing for specific antibodies may be used as a reference to determine the duration of isolation.