bluuebunny/crossref_metadata_2025 huggingface dataset:
Extraction of typical driving cycles in plateau based on improved short-stroke method
Authors: Shi Feng , Cui Shichao , Bu Han , Chen Bingshuo , He Yulong
Published: August 2020

Vehicle driving cycles is a speed time curve used to describe the characteristics of vehicle driving in a specific traffic environment. It can represent the law of speed change in the tested area. The commonly used extraction methods of driving cycles are short stroke method and Markov chain method. However, in the mountainous areas of the plateau, the poor road environment makes the driving cycles very complex. The driving cycles of automobile in plateau area has the characteristics of small proportion of idling condition, and the result of using conventional short stroke method to construct driving cycles is not ideal. In view of this, this paper proposes an improved short stroke method, which uses three parameters of speed, torque and time to divide the kinematic segments. The collected test data is divided into one kinematic segment every 60s. If the value of the 60s torque in the kinematic segment is large (greater than 85% of the total test data), it is divided into the minimum value in the 55-65s interval. Compare the actual driving cycles with the extracted driving cycles, and it is found that the driving cycles constructed by the improved short distance method are consistent with the driving characteristics of vehicles in the plateau area.
Investigation on the thermal problems of wet clutches for the tracked DCT vehicle during the launching process
Authors: Yang Zhe
Published: August 2020

Tracked vehicles usually travel on unstructured roads, and the transmission system bears heavy impact load. As one of the most vulnerable parts, wet clutches slip to transfer the engine power. To investigate the thermal condition of these wearing components, a dynamic system is built firstly to describe the launching process of the tracked vehicle. After that, a thermal resistance model is established for the gearbox cooling system based on the lumped parameter method. Combing these two models, a coupled model is proposed for the tracked DCT vehicle. From the simulation results, under the condition of launching with one clutch, the temperature rise is 42°C; while, when two clutches involved, the temperature is 21°C and 14°C respectively, which means the mitigation of the thermal problem. In addition, compared with the condition of launching with one clutch, the shock load decreased from 2250 N·m to 1745 N·m and the launching time is reduced by 1.0s by launching with two clutches.
Control strategy and simulation verification of hardware-in-the-loop system of automotive steering device
Authors: Zhen Yajing , Wang Zhaojian , Liu Jiawei , Guan Tian , Zhang Yaoming , Wang Mengen , Song Xiaoli , Zhang Dongsheng
Published: August 2020

As one of the key technologies of intelligent assisted driving simulation, hardware-in-the-loop control system has gradually become the focus of attention. Driverless has gradually become a hot topic. This paper designs a hardware-in-the-loop system of the steering device, that is, the steering device and the software system form a closed loop. This paper studies two control strategies including manual driving and driverless driving. This hardware-in-the-loop system is designed by the upper computer and controlled by the lower computer. The communication between the steering wheel and the upper computer is realized through the serial communication protocol. This hardware-in-the-loop system can simulate two modes of manual driving and driverless driving, and a visual interface is made on the display screen, which can effectively analyse the steering in real time. It provides a basic platform for the research of automobile steering and driverless driving.
Design of license plate recognition system based on capsule network
Authors: Guan Tian , Zhen Yajing , Song Xiaoli , Liu Jiawei , Wang Mengen , Wang Zhaojian , Zhang Yaoming , Zhang Dongsheng
Published: August 2020

With the development of automobile industry, the license plate, as the unique identifier of the vehicle, plays an important role in vehicle management. License plate recognition technology is mainly realized by image processing technology. It mainly includes image preprocessing, license plate positioning, character segmentation and other processes. In the actual process of license plate recognition, it is often impossible to accurately recognize the license plate due to the positional relationship such as angle. Therefore, this paper proposes a license plate recognition program based on the capsule network. First, through image preprocessing, license plate positioning, and character segmentation, and then use capsule neural network for training and simulation in order to achieve the object of accurate character recognition.
Experiments on the damping characteristics of a high-speed train hydraulic damper under low-temperature conditions
Authors: Wang Wenlin , Kong Xin , Wu Yongming
Published: August 2020

Aiming at studying the low-temperature damping characteristics of hydraulic damper, experimental research in the temperature range of -50°C∼+30°C was carried out to test the dynamic damping characteristics of a Chinese CRH high-speed train hydraulic yaw damper. Research results show that damping characteristics of the hydraulic damper will vary significantly at low temperature conditions when compared with that at normal temperatures, in general cases, the Force-displacement (F-s) curves are distorted and the damping forces are in abnormal levels; at very low temperatures, when the excitation speed is increasing, more severe empty strokes will occur during the damper compressions, so the absorption works of the damper will decrease significantly in these cases; in addition, dynamic stiffness of the damper will increase with the decreasing of temperatures, but in the compression stroke with large excitation speed, the dynamic stiffness at very low temperature conditions will drop sharply due to empty strokes. The results obtained in this study are significant for reference to improve the environment adaptability of high-speed rail hydraulic dampers and dynamics of the train operating under extreme cold weather conditions.
Application of hybrid MCGDM model combined with VIKOR method in power grid equipment optimization
Authors: Yang Yatang , Sun Gang , Liu Yansong , Chen Fumin
Published: August 2020

The evaluation index of national grid equipment procurement source value system has multi-dimensional, multilateral and multi-attribute characteristics which can cause problems, in order to solve these problems and find out optimize grid equipment suppliers, this paper put forward a hybrid multi-criteria group decision-making (HMCGDM) model combined with VIKOR algorithm. Firstly, constructing the index stereo network and introducing the intuitionistic fuzzy number (IFN) into the model in order to avoid the hard division of the decision judgment matrix. Secondly, using the ANP algorithm to calculate the joint-edge relationship value of each index at individual layers, and constructing the weighted super matrix to calculate the subjective weight value of the bottom indexes. Then, calculating the objective weight value of the bottom evaluation index by using Entropy method, and combining it with the subjective weight value to modify the overall weight value. Finally, using the VIKOR algorithm to rank the alternative programmes, and making comparison with the model formed through the TOPSIS method. The results show that the VIKOR algorithm can calculate the weight values of the bottom indexes in the complex relational network objectively and effectively, and having a good applicability for the equipment optimization.
Effect of motor characteristics on uncertainty of electric flow diverter with large pipe diameter
Authors: Li Haiyang , Li Xuejing , Chen Yuyang , Sun Lijun
Published: August 2020

Standard flow facility is a platform for performance test of flowmeters. Flow diverter is an essential component of liquid flow facility based on flying start-and-stop method, and is also a key equipment deciding the uncertainty of flow facility. In order to improve the accuracy of large flow facilities, the effects of acceleration performance and liquid shock force on the uncertainty of the flow diverter with large flow rate is analyzed. The actuation structure using servo motor and reducer to drive the flow diverter is put forward. The effect of step motor and servo motor on the uncertainty of the flow diverter is verified by real-flow test. The results of experiment indicate that servo motor driven flow diverter has faster transfer acceleration and more stable transfer process. The test results of transition time difference method show that the uncertainty of servo motor driven flow diverter is less than 0.003%.
Al/Ti-film-resistor based thermal heater with Zig-Zag configuration for MEMS application
Authors: Wang Xinghua , Jiang Zhijie , Qin Jiangyi , Liu Hongwei , Fan Guangteng , Hu Canbin
Published: August 2020

In this paper, we proposed a micro-heater based on Al/Ti-film resistors for MEMS application. The film heater, designed with unique Zig-Zag configuration, has a high heating efficiency as generated Joule heat could be confined in Zig-Zag area. Consequently, much higher maximum temperature could be achieved under the lower applied voltage, compared with conventional strategy. Based on MEMS technique, thin film based micro-heater was fabricated, and experimental characterization was carried out in room temperature. Since the micro-heaters are all in the form of thin film-resistors, the structure design is simple and fabrication process compatibility is good, which is particularly suitable in the fields of MEMS integration and actuation application.
Simulation analysis of shot peening on the surface of high-load connecting rod
Authors: Bai Long , Chen Jianjun , Liang Guoxiang , Tian Tian , Xie Lijing , Li Quanping
Published: August 2020

This paper is aimed at the high load connecting rod of the engine, which bears huge combustion pressure and inertia during the working process. Using process simulation technology to establish limited shot blast Meta-model, the law of influence of shot peening time, shot speed, shot angle, shot diameter and other parameters on the surface integrity of the connecting rod was obtained. The shot peening test of the connecting rod verified the correctness of the simulation and reached the project technical requirements.
Innovative and optimized design of automatic adjustment system for beaded rope of new diamond wire sawing machine
Authors: Wei Bangju , Liang Huiping , feng JiaHao , Liu JianWei , Xie Shenyan
Published: August 2020

Compared with traditional stone cutting technology, the diamond wire saw cutting technology is more efficient, safer and less polluting. Therefore, wire saw technology is more and more widely used in stone mining and other fields. However, the existing wire sawing machine must ensure the tension of the string bead wire at all time during the cutting process. Therefore, after cutting for a period of time, the wire breaking work must be performed, which greatly reduces the engineering efficiency, so this paper introduces a new automatic adjustment device of a diamond wire saw. Firstly, the overall structural design of the diamond wire saw is introduced. Secondly, the mechanical structure and sensing control of the automatic adjusting device of the diamond wire saw are introduced in detail. On the basis of the original wire saw, an adjustable wheel that can be automatically moved is added, and the working pressure of the string bead wire is measured in real time by a pressure sensor, the back and forth movement of the adjusting wheel can be controlled to drive the stretching of the string bead wire, thereby realizing the automatic tensioning of the string bead wire; Finally, working parameters of the wire saw are transmitted by Bluetooth or other wireless communications to achieve remote control operation of the wire saw. Through the innovative and optimized design of the automatic adjustment system for string bead wires of the wire saw, it provides a good reference for the high-efficiency, low-cost and environmentally-friendly quarrying technology.
Multi-target visual recognition and positioning methods for sorting robots
Authors: Liu Xinying , Jin Shoufeng
Published: August 2020

Aiming at the problems of complex shape and random placement of sorting robots, this paper proposes a multi-objective visual recognition and positioning methods for sorting robots. A sorting robot system with visual perception was constructed,which based on the four-degree-of-freedom DOBOT robot. What’s more, the visual system acquires images of multiple targets on the conveyor belt, the image preprocessing algorithm improves the contrast of the sorting targets, thus circular and linear structural elements are constructed in order to fill and smooth the multi-target regions segmented by the largest inter-class variance method. Besides, Establishing centroid coordinates based on image information to identify and locate connected domains of multi-target regions. The experimental results show that the method can achieve statistics on the number of multi-targets. On the basis of the hand-eye calibration of the sorting robot, the multi-objects with complex shapes and random positions are identified and positioned, and the positional information provides the autonomous grasping and sorting for the sorting robot.
Study on fuzzy duration of serial coupled iterative design tasks in product development
Authors: Tian Qi Hua , Zhang Ci , Zhu Wei , Kang Huang Jia , Zhang Yu Rong , Man Zhou Xiang
Published: August 2020

The existing serial coupling iterative design in product development has the uncertainty of the task duration, and it is difficult to solve the task duration. Based on the Markov chain method and the fuzzy theory, a fuzzy duration model of serial coupled iterative design task was constructed, and the fuzzy durations of each stage of product design task were obtained. Taking the body design process of an electric vehicle as an example, this method was applied for analysis. The research shows that the execution time of each stage task is prolonged under serial coupling iteration, and the longer the serial coupling iteration task execution chain is, the more the task execution time increases. This study has a certain reference function for complex serial coupled iterative design planning.
Accuracy analysis and errors compensation of 4-DOF reconfigurable punching robot
Authors: Ge Zhenghao , Chen Hao , Han Xiaoyu
Published: August 2020

The aims of this paper were to enhance the accuracy of the 4-DOF reconfigurable punching robot when it was working, as well as to reduce the error made by robots when they were loading and unloading materials. For these ends, by elucidating the composition and function of 4-DOF serial re-configurable punching robot, the static pose error model and the dynamic pose error model of the robot actuator were built in the present paper. Besides, MATLAB was employed to plot the actuator pose error curve. Subsequently, the pose error of the robot actuator under was delved into based on both static and dynamic factors. Afterwards, the comprehensive pose error model of the actuator was developed to plot the comprehensive pose error curve of the actuator. The perturbation compensation method was used to compensate the robot actuators. The results showed that the positioning accuracy of the robot was effectively improved. These the mentioned efforts, a solid basis was laid for manufacturing the 4-DOF reconfigurable punching robot, as well as enhancing its accuracy.
Research on finite element analysis and modelling of bolted joint
Authors: Li Pengyang , Li Wei , Wei Peiliang , Wang Quandai
Published: August 2020

The bolted joint is one of the most widely used fixed joints in mechanical structures, and has considerable impact on the dynamic characteristics of mechanical structures. Therefore, the correctness of bolt joint modeling is the key to the dynamic performance analysis and behavior prediction of the entire mechanical system. In this paper, the stiffness of the lapped beam structures was calculated according to the empirical formula for the dynamic stiffness of the joint surface, and an equivalent model of the bolt joint was established using the spring-damping element in ANSYS. Meanwhile, another equivalent model of the bolt joint was established by using the virtual material layer method. Finally, the modal test of the lapped beam structure with the bolted joint was carried out, and the simulation results obtained from the two theoretical modeling methods were compared with the modal test results. The results showed that the modeling method using the spring-damping element has higher modeling accuracy compared with the virtual material layer method, and the errors in the first six natural frequencies were within 2.2%, which verified the correctness and effectiveness of the spring-damping element modeling method, and provided a basis for the modeling of bolted joints in practical structures.
A novel control method for roll gap of roller crusher based on Fuzzy-PID with decision factor self-correction
Authors: Yang Yinwei , Fan Kai , Xu Jing
Published: August 2020

Roller crusher is widely used in solid and block material pulverizing. Roll gap between the rollers is usually adjusted to satisfy the particle size of output material. In order to realize convenient adjustment, a roll gap control scheme based on electro-hydraulic technology is designed and optimized. And Fuzzy-PID is applied to realize the automatic process. Moreover, decision factor self-correction is introduced to balance the number of Fuzzy rules and system precision. Finally, an experiment platform and some simulations are conducted to validate the performance of the proposed approach.
Fault monitoring of inner frame paper cutting transmission coupling of packaging machine based on intelligent analysis of noise
Authors: Li Guangcai , Zhen Huanju , Wang Deji
Published: August 2020

This article analyzes the noise signal of the packaging machine coupling through artificial intelligence technology, performs feature extraction and analysis on it, and realizes the status recognition and health analysis of the device. This method can successfully analyze the machinery and equipment to find the manual inspection. The problem that is neglected, the method of monitoring packaging equipment through noise energy is a new method with great potential for the actual plant environment.
Study on mechanical properties of thin-walled cavity structure with a large aspect ratio for ultra-precision optical instrument
Authors: Li Lin , Zhong Jun , Sui Jie , Zhang Yun-fang , Lv Wei-zhen , Wang Xiao-yan
Published: August 2020

The maximum size scale of a Thin-walled Cavity Structure (TSC) with A Large Aspect Ratio (TCSA) for ultra-precision optical instrument used in space station is more than 500. The TCSA should be strong enough, and at the same time, its mass should be lighter. Firstly, the characteristics of the thin-walled structure with ring-rib and longitudinal rib cavity were discussed, and the optimization design method of the rib structure was put forward based on the rib contribution theory. Secondly, the mathematical model was established, and the sensitivity analysis of the design variables and objective functions was carried out. On this basis, the iterative formula of the optimization of the rib structure was derived, and the optimization design of the TCSA was carried out. Finally, the system level simulation analysis and mechanical test were carried out for the optimized structure. The results show that the maximum relative changing rate of the first-order frequency before and after the test is 2.05%, the maximum relative error of the first-order frequency between the calculation mode and the test mode is 1.23%, and the fundamental frequency of the whole instrument is greater than 120Hz, which proves that the finite element model is more accurate. The displacement of random response of TCSA after optimization is 0.61mm, the maximum stress is 39.2mpa, far less than the allowable stress, which meets the mechanical requirements, and the adopted optimization method was proved to be useful. At the same time, the high precision optical instrument with good mechanical properties was also proved.
Research on thin spray-on technology and equipment of coal mine
Authors: Min Fusong , Chen Ke , Li Xiangyang , Pang Shudong
Published: August 2020

Based on the existing problems and demands of coal mine support, as well as the advantages of thin spray-on liner in coal mine support and gas sealing, the research on thin spray-on material is carried out. Two kinds of thin spray-on products are qualitatively analyzed, and the thin spray-on equipment is developed and applied. The results show that the performance of thin spray-on material meets the requirements of coal mine. The production efficiency and construction speed are improved, and the underground material transportation volume and the number of workers are reduced. At the same time, gas infiltration is reduced and the safety of the underground is improved.
Synthesis and networking of tetrahedral deployable mechanism based on screw theory
Authors: Huang Zhirong , Ma Xiaofei , Hu Fei , Zhu Jialong , Xu Yundou
Published: August 2020

Aiming at the synchronous motion of tetrahedral deployable unit, the kinematic pair is designed and the coupling motion branch is synthesized based on screw theory. The optimal deployable unit is determined by the application. According to the networking requirements, a networking mechanism composed of multiple units with coupling degree of freedom (DOF) is synthesized. The application of the screw theory in the configuration synthesis of deployable mechanism is realized in this paper. The mechanism is suitable for the deployable mechanism of satellite antenna reflector or other space surface deployable support mechanism, which has broad application prospects.
A simple process optimization route to fabricate curved bionic compound eye array
Authors: Huang Shengzhou , Wang Lei , Zheng Yanchang , Su Yongsheng , Wang Fengtao
Published: August 2020

In this paper, a complete and simple process optimization route for the curved bionic compound eye (BCE) array fabrication is presented based on digital micromirror device (DMD) maskless lithography. Firstly, based on the study of edge bulge effect in the thermal reflow process, a proper curved BCE structure is designed. Then, through the optimization of multilayer coating process it can obtain a better uniformity of different photoresist layer and accurate thickness. Next, combined the DMD maskless lithography technology with the Poor Man’s dissolution rate monitor (DRM) approach, well-preformed hierarchical cylindrical structure can be simply fabricated. Lastly, the curved BCE structure can be obtained precisely by choosing the reasonable process control parameters, which depended on the study of two-step thermal reflow processes. This process optimization route makes it very easy to realize the curved BCE array structures with different ommatidium shapes. Experimental results showed the effectiveness of our process optimization method. The presented method is expected to provide a fast, economic and simple strategy for curved BCE array fabrication.
A method based on ASTME1012 to adjust the alignment of the material testing machine
Authors: Xu Jian , Zhao Yinming , Chai Jixin , Chen Kexing
Published: August 2020

A method by using strain-gauged transducer to adjust the alignment of the materials testing machine is introduced in this paper. In order to improve the accuracy of the material test, the alignment of the material testing machine should be adjusted before tests. A transducer with three levels of strain gauges is applied before the specimens are tested. By calculating the bending stress according to the equation in ASTME1012,an adjustment suggestion to reduce the angular misalignment and concentric misalignment is given by the calculation results. Through adjusting the direction and position of the grips until the value of the strain gauges meet the requirement, the misalignment of the material testing machine will be removed.
Experimental study on vibration fatigue of a certain chassis
Authors: Cao Weizhong , Hu Changming , Liao Tao , Rui Shen
Published: August 2020

The chassis is the structure for installing and protecting various circuit units, components and mechanical components inside the electronic device. Vibration fatigue damage is a major form of structural damage, and the vibration fatigue life prediction of the chassis structure is of great significance. The theoretical calculation of structural vibration fatigue life has frequency domain method and time domain method, but it has certain limitations. The theoretical calculation method can not accurately obtain the vibration fatigue life of the structure. According to the actual structure of a chassis, this paper designs and processes a test model of a chassis, applies a random vibration load to the vibration table, and performs vibration fatigue test to predict the vibration fatigue life of a chassis structure. The results show that the vibration fatigue life of the chassis is 40 hours, and fatigue fracture occurs first at the pin.
Analysis of the structure of wood-plastic composite coated co-extrusion head
Authors: Ge Zhenghao , Chang Hongli , Ren Shanshan
Published: August 2020

In order to further solve the problem of the flow path of the head of the existing wood-plastic composite co-extrusion, the structural defects of the head are accurately found. This article first simulates the core and shell flow channels separately to simulate whether they are uniformly extruded and whether the exit speed is consistent. It is further analyzed that the cause of the uneven coating of the part is the problem of the shell flow channel and its structure. It does not meet the design requirements. Then, by proposing a variety of different flow channel structure optimization schemes, further simulations are performed, and the fluid flow trend is analyzed based on the simulation results. First of all it is determined that the existing flow path shape itself has problems. Considering the structure of the overall nozzle flow channel, based on the analysis of the flow channel trend, a new solution for the design of the co-extrusion ring flow channel is proposed. Further solve the structural problem of the coating head,which improved the design efficiency and reduced the waste of personnel and materials caused by continuous die testing. It has certain reference value for follow-up.
Study on molding technique for millimeter-wave radome with frequency selective surface
Authors: Yang Chunxia , Zhu Yongming , Gui Tao
Published: August 2020

In the paper, the molding process of the millimeter-wave radome with frequency selective surface was studied, and the key factors were discussed such as the selection of the material, the design of the mould and the curing parameters. The millimeter-wave radome with FSS has the high requirement for thickness uniformity and surface precision. The layout design and the moulding parameters control were discussed to achieve the high performance of the radome. The testing results show that the manufactured radome has the smooth surface and thickness precision of ±0.1mm. The average transmission efficiency of the radome working at the operating frequency and in the sweep range is ≥90%. The performances of the radome entirely meet the design requirements.
Fracture analysis for reasons of bellows with braided hose
Authors: Sun Gang , Mao Lina , Li Xiaolin , Sun Xiaona , Huo Ningfei
Published: August 2020

The fracture of metal braided hose around bellows were found in working condition. Then, the macroscopic analysis, fracture analysis, metallographic analysis and chemical composition analysis were performed separately by using Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS) and other equipment. The causes of the damage in the braided hose are studied in this paper. The results show that the pitting corrosion and stress corrosion caused by chloride ion are the major factors of wire breakage. In follow, the preventive measures for such accidents for this fracture accidents are put forward.
Natural lubrication mechanism of twisting in ring spinning and its experimental analysis
Authors: Chen Ge , Gao Yongshan , Zhou Honglei , Xue Wenliang
Published: August 2020

In the spinning process, the natural lubricating film between the ring and the traveller changes the dry friction between them. In this paper, the composition of natural lubricating film is analyzed by DA1-180M microscope observation and Fourier infrared spectrometer. The eddy current sensor was used to detect the movement of the traveller on-line. The number of abnormal acceleration of the traveller reflects the stress stability of the traveller, and the lubrication effect of the natural lubrication film was analyzed. The experiment shows that the natural lubricating film is composed of the spun fiber, which can make the stress of the traveller relatively stable in the short term, but in the long term its lubricating effect cannot eliminate the wear between the ring and the traveller.
Structural analysis of coreless spoiler
Authors: Song Jia , Lv Haicui , Wang Yanli
Published: August 2020

In this paper, a coreless spoiler is proposed to be an alternative solution for moisture absorbed honeycomb core. The honeycomb core is removed from the spoiler and the coreless spoiler is analyzed by using finite element tool, Abaqus. The results show that the upper skin fails at region near to the actuator, Tsai-Hill is more than 1. Few options, such as ßrib, spar and Carbon Fiber Reinforced Plastic (CFRP) patch are introduced to support the weak region of coreless spoiler. The effectiveness of these notions is evaluated based on Tsai-Hill failure. The spar outperformed the other options. Only the spar is capable of giving sufficient support to the coreless spoiler and the structure does not fail in term of Tsai-Hill index.
The collapse response of web-core sandwich panels partially filled with metallic foams under drop-weight impact
Authors: Xie Zhongyou
Published: August 2020

Thin-walled web-core sandwich structures are widely applied due to their weight specific mechanical performance. When subjected to a transverse load, the sandwich structures are apt to undergo local deformation which would considerably decrease the cross-sectional height and their global load resistance, especially under a concentrated load. In the paper, a novel method is proposed only to fill the upper compressive region of the web-core sandwich panels other than the whole cross section with metallic foams, which would effectively restrain the local deformation at the cost of slight increase of the structural total mass. The collapse response of web-core sandwich panels with four different reinforcing configurations under drop-weight impact is investigated using ABAQUS code. The numerical results show that the two empty panels without foam filler have a close valley force and the foam filler significantly improves the structural load-carrying capacity after the initial elastic peak force. Moreover, it is noticeable that the partially filled panel suggested here demonstrates the similar load resistance to the fully filled one and much more weigh specific energy-absorbing performance than the other three sandwich panels.
Machine learning for faster and smarter fluorescence lifetime imaging microscopy
Authors: Mannam Varun , Zhang Yide , Yuan Xiaotong , Ravasio Cara , Howard Scott S
Published: August 2020

Fluorescence lifetime imaging microscopy (FLIM) is a powerful technique in biomedical research that uses the fluorophore decay rate to provide additional contrast in fluorescence microscopy. However, at present, the calculation, analysis, and interpretation of FLIM is a complex, slow, and computationally expensive process. Machine learning (ML) techniques are well suited to extract and interpret measurements from multi-dimensional FLIM data sets with substantial improvement in speed over conventional methods. In this topical review, we first discuss the basics of FILM and ML. Second, we provide a summary of lifetime extraction strategies using ML and its applications in classifying and segmenting FILM images with higher accuracy compared to conventional methods. Finally, we discuss two potential directions to improve FLIM with ML with proof of concept demonstrations.
Medication appropriateness on an acute geriatric care unit: the impact of the removal of a clinical pharmacist
Authors:   The Investigators of the MAGIC-PHARM Study, Khazaka Michael , Laverdière Jeanne , Li Chen Chen , Correal Florence , Mallet Louise , Poitras Mariane , Nguyen Patrick Viet-Quoc
Published: August 2020

Background

evidence is largely available indicating benefits to adding a pharmacist on acute care wards. The benefits of maintaining pharmacotherapeutic consultant services on a geriatric ward remain unexplored.

Objectives

to determine the impact of the removal of a clinical pharmacist from an acute geriatric ward on patients’ Medication Appropriateness Index (MAI) scores, admission-related outcomes and drug burdens.

Methods

researchers consulted the archives for records of patients admitted to the geriatric care unit before and after the pharmacist’s withdrawal. The primary outcome of differential MAI scores and secondary outcomes of rehospitalisations, emergency department visits, durations of hospitalisation and differential drug count were compared pre- and post-intervention. An interrupted time series analysis regression model was used for the primary outcome.

Results

a total of 305 patients admitted before (n = 208) and after (n = 97) the pharmacist’s withdrawal were included in the study. The intervention had a significant impact on the primary outcome, increasing the relative differential MAI score (adjusted mean) by 9.3 points (95% confidence interval 3.9–14.6). As for the secondary outcomes, differences in admission-related outcomes were non-significant but the mean differential drug count significantly increased post-intervention from 0.02 to 1.36 (P < 0.001).

Conclusion

the removal of the pharmacist led to an increase in inappropriate drug prescription. Careful consideration should be given to decisions regarding the removal of the pharmacist from acute geriatric care teams.
Planning to move into a nursing home in old age: does sexual orientation matter?
Authors: Buczak-Stec Elzbieta , König Hans-Helmut , Hajek André
Published: August 2020

Background

Qualitative studies showed that community-dwelling Lesbian, Gay, Bisexual and Transgender (LGBT) individuals perceive that LGBT individuals are discriminated against in nursing homes (NHs) due to their sexual orientation. Therefore, the objective of this quantitative, population-based study was to investigate the link between sexual orientation and planning to move into a NH in old age.

Methods

Cross-sectional data from the most recent sixth wave of the nationally representative German Ageing Survey (n = 4,645) were used. The sexual orientation was dichotomized (heterosexual; sexual minorities including gay/lesbian, bisexual and other). Planning to move into a NH in the future (yes/no) was our outcome measure. Multiple logistic regressions were performed (adjusting for various socioeconomic, psychosocial and health-related covariates).

Results

Regressions showed that sexual orientation was not significantly associated with plans to move to a NH. Preference to move into NH were consistently positively associated with age (OR: 1.04 (1.02–1.07), not having at least one child (OR: 2.17 (1.41–3.36)), high education (OR: 3.82 (1.32–11.11)), greater loneliness (OR: 1.44 (1.05–1.96)) and worse physical functioning (OR: 0.99 (0.98–1.00)).

Conclusions

Unexpectedly, our results showed that plans to move to a NH did not differ significantly between heterosexual individuals and sexual minorities. This indicates that sexual orientation does not play a significant role in shaping preferences around moving into a NH ‘in general’. In contrast, other factors like age, greater loneliness and worse physical functioning were important. Those factors should be taken into account when shaping and updating policies on nursing homes.
Gender-Specific Drinking Contexts Are Associated With Social Harms Resulting From Drinking Among Australian Young Adults at 30 Years
Authors: Meque Ivete , Salom Caroline L , Betts Kim S , Najman Jake , Alati Rosa
Published: August 2020

Aims

Understanding contexts in which social harms from drinking occur can help develop context-based harm reduction efforts. However, there is little knowledge of specific drinking contexts where such harms occur and whether these are gender or age specific. We aimed to investigate associations of a range of drinking contexts and social harms from drinking among young adults at age 30.

Methods

We used data from 2187 30-year-old adults. Latent constructs of gender-specific drinking contexts were created using factor analysis. We performed multivariate logistic regression between drinking contexts and a range of social harms from drinking, separately by gender.

Results

After accounting for social roles and binge drinking, gender-specific solitary drinking contexts (‘home drinking’ for men and ‘daytime drinking’ for women) were positively associated with marital problems and problems with other family members and friends. Conversely, ‘social drinking’ was not. Work-related drinking among men was associated with marital/intimate relationship problems and friendship problems. After accounting for mental health symptoms, women’s home drinking was associated with marital problems.

Conclusion

We found that experiences of social harms from drinking at 30 years differ depending on the drinker’s gender and context. Our findings suggest that risky contexts and associated harms are still significant among 30-year-old adults, indicating that a range of gender-specific drinking contexts should be represented in harm reduction campaigns. The current findings also highlight the need to consider gender to inform context-based harm reduction measures and to widen the age target for these beyond emerging adults.
Warrants to conserve
Authors: Stanhope Jonathan
Published: August 2020

This paper is about reasons to conserve, in particular why some things warrant being conserved. In discussing G. A. Cohen’s conservatism, I find strains of four answers to the question why, presumptively, we should not sacrifice existing valuable things, a fortiori destroy them for no overall gain in value. After criticizing the first three, I develop the fourth into a deflationary proposal. That is, it implicates just one sub-type of value and takes certain first-order properties – or the value supervening on them – directly to warrant conservation of the things instantiating them. Rather than sanitizing status quo bias, moreover, my proposal happily bypasses it.
XV—On Consistency and Existence in Mathematics
Authors: Dean Walter
Published: August 2020

This paper engages the question ‘Does the consistency of a set of axioms entail the existence of a model in which they are satisfied?’ within the frame of the Frege-Hilbert controversy. The question is related historically to the formulation, proof and reception of Gödel’s Completeness Theorem. Tools from mathematical logic are then used to argue that there are precise senses in which Frege was correct to maintain that demonstrating consistency is as difficult as it can be, but also in which Hilbert was correct to maintain that demonstrating existence given consistency is as easy as it can be.
LongAGE: defining breakpoints of genomic structural variants through optimal and memory efficient alignments of long reads
Authors: Tran Quang , Abyzov Alexej
Published: August 2020

Defining the precise location of structural variations (SVs) at single-nucleotide breakpoint resolution is a challenging problem due to large gaps in alignment. Previously, Alignment with Gap Excision (AGE) enabled us to define breakpoints of SVs at single-nucleotide resolution; however, AGE requires a vast amount of memory when aligning a pair of long sequences. To address this, we developed a memory-efficient implementation—LongAGE—based on the classical Hirschberg algorithm. We demonstrate an application of LongAGE for resolving breakpoints of SVs embedded into segmental duplications on Pacific Biosciences (PacBio) reads that can be longer than 10 kb. Furthermore, we observed different breakpoints for a deletion and a duplication in the same locus, providing direct evidence that such multi-allelic copy number variants (mCNVs) arise from two or more independent ancestral mutations.

Availability and implementation

LongAGE is implemented in C++ and available on Github at https://github.com/Coaxecva/LongAGE.

Supplementary information

Supplementary data are available at Bioinformatics online.
Allometric scaling in two bushcricket species (Orthoptera: Tettigoniidae) suggests sexual selection on song-generating structures
Authors: Rebrina Fran , Anichini Marianna , Reinhold Klaus , Lehmann Gerlind U C
Published: August 2020

In acoustically communicating bushcrickets (Orthoptera: Tettigoniidae), most signal properties are influenced by the dimensions of the stridulatory apparatus, which in turn reflects body size and condition of the signaller. Females can assess male quality based on acoustic signals, suggesting that male stridulatory structures may be under sexual selection. We investigated scaling relationships between stridulatory structures, body size and body mass in males of the bushcricket Poecilimon veluchianus veluchianus, in comparison to the congeneric Poecilimon ampliatus. Stridulatory structures in P. v. veluchianus exhibited strong left–right correlation and coupling with body size and mass, indicating stabilizing selection for functional integration. In addition, sound-generating (the width of stridulatory teeth) and sound-radiating (mirror area on the right tegmen) structures scaled hyperallometrically to tegmen area, suggesting that both are under sexual selection. Finally, interspecies comparison revealed a steeper slope in tegmen area and stridulatory file length in relation to body size in P. ampliatus than in P. v. veluchianus, implying stronger sexual selection in the former, smaller species. Our study emphasizes the significance of a comparative allometric approach in elucidating evolutionary patterns of sound-generating and -radiating structures.
Ancient divergence, a crisis of salt and another of ice shaped the evolution of the west Mediterranean butterflyEuchloe tagis
Authors: Marabuto Eduardo , Pina-Martins Francisco , Rebelo Maria Teresa , Paulo Octávio S
Published: August 2020

The Mediterranean region is an extremely complex hotspot where, since the Miocene, extensive geological, habitat and climate changes have taken place, alternating between warm and cold periods. These phenomena have taken a toll on the genetic composition of species, and surviving lineages have often adapted locally and diverged to the point of (complete) speciation. To study these phenomena, in this study we used one of the most enigmatic butterflies, the Portuguese dappled white, Euchloe tagis, a west Mediterranean endemic with fragmented, morphologically differentiated populations whose status have long been disputed. Even its affiliations with other Anthocharidini are largely unresolved. We used mitochondrial and nuclear markers under a phylogenetic and phylogeographical framework to evaluate its placement among relatives and population differentiation, reconstructing its evolutionary history. We found that this species had a Miocene origin ~15 Mya and was nearest to Euchloe s.s. and Elphinstonia. Its populations showed high genetic diversity but all coalesced to 5.3 Mya, when European and all but one African population diverged. Our multiple findings concerning the evolution of E. tagis through a changing, narrow habitable area might provide a more general perspective on how species survive within this hotspot of paramount importance.
Drug Control Policy, Normalization, and Symbolic Boundaries in Amsterdam’s Coffee Shops
Authors: Dickinson Timothy , Jacques Scott
Published: August 2020

This study examines the relationship between drug control policy, normalization and symbolic boundary work among drug traders. Taking from interviews with 50 personnel in Amsterdam’s coffee shops, we find that Dutch drug policy shapes their understanding of what comprises morally acceptable drug use and sales. Conversely, the rules set by the state also guide personnel’s definitions of what is morally unacceptable: using hard drugs or committing predatory crimes. To normalize their own involvement with cannabis, personnel must identify potential rule breakers and criminals. To do so, they construct symbolic boundaries differentiating themselves from these persons. We conclude by discussing the theoretical implications of our findings for normalization and symbolic boundaries and by suggesting a potential negative secondary impact of cannabis decriminalization or legalization: the further marginalization of hard drug users.
Opening the Time Capsule of ACEs: Reflections on How we Conceptualise Children’s Experiences of Adversity and the Issue of Temporality
Authors: Devaney John , Frederick John , Spratt Trevor
Published: August 2020

In this article, we engage with some of the fundamental concepts underpinning the original adverse childhood experiences (ACEs) study and subsequent work, whilst recognising that the terminology of ACEs has in some ways become reductionist and problematic. Although an imperfect concept covering a range of childhood adversities at a personal, intrapersonal and community level, ACEs have utility in bridging scientific and lay communities. The evidence clearly identifies that ‘numbers matter’ and that whereas children may be able to cope with a little adversity over a short period of time when they have good support networks, too much adversity over too long a time period, even with good support, will be problematic for the child and their family. Alongside exploring the cumulative impact of adversity, social workers and other professionals need to engage with the temporal component of when adversity is experienced, and for how long, together with the consequences for helping services in deciding when to intervene and for what period of time. This opens the discussion of who is best placed to support children and families experiencing certain types of adversity and how we think about structural issues such as poverty and community violence within the ACEs discourse.
Covid-19 and the ‘new normal’: are remote video consultations here to stay?
Authors: Bidmead Elaine , Marshall Alison
Published: August 2020

Introduction

During the UK Covid-19 lockdown, video consultations (telemedicine) were encouraged. The extent of usage, and to which concerns to earlier implementation were set aside, is unknown; this is worthy of exploration as data becomes available.

Sources of data

Sources of data are as follows: published case studies, editorials, news articles and government guidance.

Areas of agreement

Video can be clinically effective, especially where patients cannot attend due to illness or infection risk. Patients are positive, and they can benefit from savings in time and money. Adoption of telemedicine is hindered by a range of known barriers including clinician resistance due to technological problems, disrupted routines, increased workload, decreased work satisfaction and organizational readiness.

Areas of controversy

Despite policy impetus and successful pilots, telemedicine has not been adopted at scale.

Growing points

Increased use of telemedicine during the Covid-19 crisis presents opportunities to obtain robust evidence of issues and create service transformation effectively.

Areas timely for developing research

Examination of telemedicine use during the Covid-19 crisis to ensure that the benefits and usage continue into the post-lockdown, ‘new normal’ world.