bluuebunny/crossref_metadata_2025 huggingface dataset:
Research of nickel-based coatings erosion-corrosion wear
Authors: Nazarov A N , Prozhega M V , Yu Ivannikov A , Boytsova O V , Novikov A V
Published: March 2020

This article demonstrates the results of testing a nickel-based coating deposited by plasma spraying. According to the criterion of the relative volumetric wear rate, samples were compared at different concentrations of abrasive, impact angle of 45° and 90°, in an acidic media. A wear of a Ni coating with a steel substrate has been compared.
Interaction model of one jaw of a vibrating jaw crusher with the processed rock, taking into account the properties of the electric motor
Authors: Altshul G M , Gouskov A M , Panovko G Y , Shokhin A E
Published: March 2020

Vibratory jaw crushers are modern machines for grinding and rock crushing. Single jaw of vibratory jaw crusher is considered in this paper. Phenomenological model of interaction of the jaw and rock is proposed. Two options for considering the power of an unbalanced drive are considered. In the first, an unbalanced vibrator has a constant angular velocity relative to the bed. In the second, the electromechanical characteristics of the electric motor, which drives the unbalanced vibrator, are taken into account. The impact of crushed material on the vibrational modes of the jaw and the rotation characteristics of the vibrator for each of the vibration excitation variants is considered. The distribution of the technological load obtained based on this model over the jaw is shown

A post-publication change was made to this article on 20 Mar 2020 to correct an author affiliation.
The impact of nonorthogonality of the axial electromagnetic bearing disk on the stability region of a rigid rotor on a full electromagnetic suspension
Authors: Kapitanov D V , Bobylkov A G , Kapitanova O V
Published: March 2020

The paper presents the results of a research of the stability of a rigid homogeneous rotor with a symmetrical relative to the middle arrangement of radial EMB, supported in the vertical direction by an axial EMB. In the first part of the work, the researches were held using a proportional-differential regulator in the system. In the second part of the work was considered the impact of the control function parameters in the cases of instantaneous generation of the displacement signal and with delay.
Special Rotordynamics: Simulation of Contact Rotor System
Authors: Nikiforov A
Published: March 2020

The paper discusses four contact models used in the dynamic analysis of rotor systems. A mathematical imperfection of two models by a real example is shown. It consists in a significant overstatement of the calculated whirl-whip speed in case of the rotor slipping on the stator.
Investigation of dynamic characteristics of spindle units of CNC lathes batch
Authors: Sabirov F S , Bogan A N , Mikhaylov I S
Published: March 2020

Studies of the dynamic characteristics of a batch of CNC lathes of the same model, in particular, the frequency response of spindle units, which are obtained experimentally by pulsed excitation of an elastic system, are considered.
Comparison between three mathematical models of three well defined ultrasonic NDT cases
Authors: Semenova M , Wirdelius H , Persson G
Published: March 2020

Ultrasonic nondestructive testing (NDT) is commonly used for in-service inspection in different areas. But reliability of NDT method is highly dependent on the equipment and crack features. Although, it is possible to use thoroughly validated mathematical models to avoid complicated and costly experimental work, when it is necessary to qualify new procedures. Finite Element Model (FEM) is a powerful tool, which is commonly used for such cases. In this paper three mathematical models of three well defined cases will be compared with each other.
Capabilities of vibration cutting at turning of hard-to-cut materials and built-up surfaces
Authors: Vladimirov A A , Afonin A N , Makarov A V
Published: March 2020

The article describes the results of vibration turning research for cutting the parts produced of austenitic steel of high ductility and strength, as well as for the machining of the surfaces reworked by the method of build-up welding. Lathe turning with a superposition of pendular-type harmonic vibrations to the cutting tool is one of the productive cutting methods of austenitic steel, from which parts of mining machines and equipment are made, and built-up surfaces as a result of repair of various parts of mining equipment. Selection of optimal amplitude-frequency parameters of cutting tool vibration allows to increase a period of tool material lifetime, to ensure constant process of chip breaking and helps to reduce a cutting force. When turning the materials with generation of pendular vibrations in cutting zone, some phenomena occur that are not observed during cutting without vibrations. Based on the results of tests of vibration turning the main facts were defined, which have the greatest influence on lifetime of cutting tools during cutting of austenitic class steels and built-up surfaces, it is expedient to consider: vibration velocity, vibration acceleration, vibrating influence energy dispersion. The concept of the vibration impact generalized function (VIGF) was introduced, which allows to describe mathematically three main factors of pendulum vibrations influence in the cutting zone. The equation of the mathematical model of vibration turning with VIGF is presented, which describes the dependence of the tool lifetime period on vibration parameters. The process of generation and breaking of the chips when turning the hard-to-cut materials is studied. The fields of temperature distribution in the cutting zone at turning are investigated.
Personalized biomechanical analysis of mandible teeth loosening during periodontal treatment with non-removable polymer splints with considering the different approach to physical and mechanical characteristics determining of bone tissue
Authors: Levchenko I M , Gribov D A , Krupnin A E , Arutyunov S D
Published: March 2020

A 3-dimensional finite element model of mandible anterior section, including a segment of mandibular bone tissue, four incisors, periodontal ligament (PDL), polymethylmethacrylate (PMMA) immobilizing splint of 0.5 mm thickness was developed. The stress-strain state of the model components is considered for the cases of a splinting structure presence and absence from the action of a typical occlusal load F = 200 N. The influence of the physicomechanical properties determining method for mandible bone tissue on the obtained results is evaluated.
Research of orientation characteristics of visual intersection illusion
Authors: Rakcheeva T A , Kostoev A T
Published: March 2020

During visual perception of an inclined line, partially passing behind an opaque object, an error (Poggendorff illusion) arises assosiated with an inadequate extrapolation of the line extension after its passing behind the object. The quantitative relations of the illusion values of displacement from the geometric and orientational parameters of the Poggendorf configuration are determined.
Generative design of biosimilar structures
Authors: Stepanyan I V
Published: March 2020

The article discusses ideas at the junction of various paradigms for the synthesis of new structures and shapes, where part of the calculation processes is based on computer technology using non-Euclidean geometry. Algorithms for generating bio-similar surfaces, parts, and textures that can be used in industry, in particular in additive technologies are given. The article has the descriptions of equations based on hyper-complex systems and conditions of the analyticity of functions. The algorithms for generating biosimilar surfaces can be used in generative design. While determining the parameters of hypercomplex systems and assessing the mechanical characteristics of the final products require additional research, the relative simplicity of mathematical algorithms for generating structures and shapes with non-Euclidean geometry opens up the possibility of applying the proposed method in various fields.
Use of the chord method for analyzing workspaces of a parallel structure mechanism
Authors: Antonov A V , Chernetsov R A , Ulyanov E E , Ivanov K A
Published: March 2020

The size and shape of the mechanism working area are one of the most important criteria of its performance. Known approaches to the analysis of the workspace, such as the geometric method or the discretization method, have a number of features that limit their effective application. This paper considers the optimization chord method for determining the working areas of various types on the example of a planar parallel mechanism. The simulation results for maximum, constant orientation and dextrous workspaces are presented.
About features of management of mobile robots with stepping movers of a rope type in a water environment
Authors: Briskin E S , Gulevsky V V , Penshin I S , Sharonov N G
Published: March 2020

The methods of moving robotic platforms having in their arsenal either an anchor-rope or an anchor-rope-tracked mover are analyzed. The algorithms of operation of caterpillar-anchor-cable movers of various designs and gait algorithms for a platform with an anchor-cable mover are determined.
About determination of the bearing capacity of the soil on the route of the walking robot with orthogonal drives
Authors: Burkhanov A A , Ryabova Y S , Ustinov S A , Leonard A V , Gavrilov A E
Published: March 2020

Problems of determining of bearing ability of a ground on a route of the walking robot with orthogonal drives are considered. The approach for definition of bearing ability of a ground with use of a support orthogonal walking drives a method of penetration is offered. The architecture of information - measuring system of the walking robot providing movement on a route with determining of bearing ability of a ground is offered.
Increasing the effective workspace of the planar 3-RRR mechanism by using kinematic redundancy
Authors: Erastova K G
Published: March 2020

A significant issue of parallel mechanisms is the existence of singularities where the end-effector can lose their mobility or cannot be controlled. The closeness to singularities affects the performance of the mechanism, for example, the actuation efforts increase, thus reducing the effective workspace of the mechanism. Kinematic redundancy can be used for avoiding the singularity and increase the effective workspace. The approach is considered on the example of a planar 3-RRR mechanism.
Holes manufacturing technology influence on the strength of fibrous composites
Authors: Kh Akhmedshin E , Polilov A N , Tatus’ N A
Published: March 2020

The hole effect on the unidirectional composite specimen bearing capacity describes in the article describes. A comparison of the finite element calculation of the plates with holes made in various ways with experimental data is carried out. Good convergence of the FEM calculation and experimental data is shown.
Approach to cross-platform 3d-models binary format development
Authors: Alpatova M.V. , Demidov D.G. , Vinokur A.I. , Krupenin V.L.
Published: March 2020

The article presents the process of analysis, processing and compression of 3D objects for their further transfer to the end user over the network. The necessity to optimize the disk storage occupied by 3D textured models and to convert data into a format compatible with any robotic systems is a subject of the discussion. Comparison of a developed binary format with counterparts is resulted.
Study of adhesive line quality and capacitance parameter in shaft/bush joints
Authors: Maslennikova E V
Published: March 2020

This article contains the analysis of application of adhesive joints and peculiarities of the control carried out for these joints. Requirements to a control unit, which shall be built into a conveyer line, are described. Besides, a new technique of shaft/bush joints is analyzed; a new control method is tested based on this technique. Obtained results allow making conclusions regarding the applicability of this method and its purposefulness.
Definition of service area of agricultural loading robot with manipulator of parallel-serial structure
Authors: Nikolaev M E , Nesmianov I A , Zaharov E N
Published: March 2020

For the mechanization of loading and transport work when harvesting vegetables packed in nets, the design of the loading manipulator on the mobile chassis is proposed. The design feature is that the component of the loading manipulator is a mechanism of parallel structure - a tripod. The required number of degrees of freedom of capture for the quality assurance of the process is substantiated.
Correct FRP tensile specimen
Authors: Zhavyrkin V V , Polilov A N , Arutjunova A S , Tatus’ N A
Published: March 2020

The article depicts a problem of creating a correct composite tensile specimen. Loading of the sample was carried out by shear stresses applied on the gripping part of its lateral surface. The calculation of the stress state of the object of study was carried out with the use of ANSYS software. The results obtained were compared with a standard flat sample.
Stability system design of flying body elevator control
Authors: Yass Muhammad A. R , Abdulaziz Abrahem Hussian
Published: March 2020

This paper, suggest the solution of a dynamic non-homogenous longitudinal pitch-mode flying body equation to analysis motion stability by determining the transfer function of a pitch mode control system from feedback control system diagram. It used a flying actuator design system to estimate optimum system stability and control using the time response method and root locus diagram for different gain values (K) and Gyro sensitivity values (GR) to obtain the best stability, peak value and time response. The results shows that the best stability and control behavior are achieved when K=1.4 and GR=1.2.
DESIGN AND IMPLEMENTATION OF AN AUTOMATIC CONTROL SYSTEM TO AVOID FOULING IN PIPES WITH BLOW DOWN HEAT RECOVERY IN STEAM BOILERS
Authors: Ibrahim Raheek I. , Humod Abdulrahim T. , Essa Najat A.
Published: March 2020

The aim of the present work is to solve the problem of fouling in boiler pipes and improve energy efficiency of steam boilers in the south refineries company, Al-Basrah province, Iraq. An automatic control system with a novel electronic circuit has been proposed to achieve this aim. This system consists of an on-line conductivity sensor and a conductivity monitor connected to an additional resistance to measure the concentrations of dissolved solids in boiler water. A square wave feedback has been employed to determine the levels of solid concentrations and controls the surface blow down process through electronic circuit. This circuit consists of a D.C power supply, an amplifier, a rectifier, comparators and a driver sub-circuits for solenoid valve. The driver sub-circuit consists of two transistors and three relays. The solenoid valve is used with throttle valve to control the flow rate of boiler blow down water. Two flow meters are used to measure blow down and feed water flow rates. The design and implementation of a heat recovery unit is also included. It consists of a heat exchanger (shell and coiled tube) type used to recover heat energy from blow down water. To measure the inlet and outlet temperatures of feed water and blow down water, four (k-type) thermocouples were used. A pump was used to pump feed water from the storage tank in to the boiler. To automatically control water level inside the boiler two electrodes (water level sensor) were used integrated with the float less level switch circuit. The experimental results proved the effectiveness of the innovative control system in improving boiler efficiency and in fouling control through enhancing the blow down process and reducing indirect losses. The blow down quantity reduced from 2244.897 kg/h to 1111.111 kg/h. Which provided 27210.864 kg/day of blow down water. Hence, saved 158450201.2 ID/year or 83.16% of the energy lost with blow-down water can be recovered using heat-recovery unit with an energy saving of 103411.8 MJ/day. Which will save a mass of fuel equals to 482.46 ton/year. The automatic control system proved to be a good solution for saving energy and reducing harmful emissions to the environment and it contributes to the maintenance of sewage pipes from damage caused by the heat of discharged water.
A Hardware Implementation of Neuro-PMD Model classifier based FPGA
Authors: Ali Wisam H. , Jaafar Ismail Sammar , Jaafar Ismail Reem
Published: March 2020

A classifier (polarization mode dispersion) has been introduced in this article. The suggested NeuroPMD classifier uses various types of fiber optics, and it’s deviation effect properties to handle light transmission using Polarization Mode Desperation (PMD). The suggested classifier receives an unspecified signal with many percentage points, classifies it base on stored signals and shows the reliability of the received signal. The proposed system is built using VHDL, modeled by the Xilinx package (ISE 9.2i), the proposed NeuroPMD is implemented on the Spartan-3A XC3S700A kit. simulation and Implementation behavioral results demonstrate that the proposed model satisfies the specified operational requirements and gives solutions to overcome the scattering problems in the optical systems.
Obstacle Avoidance Method for Highly Redundant Robotic Arms
Authors: Hameed Firas S. , Alwan Hassan M. , Ateia Qasim A.
Published: March 2020

Obstacle avoidance is an important concept to be considered when a robotic system is installed in an environment. Obstacles within the working space of a robotic system can prevent the robot from performing the tasks assigned to it properly; hence, the designer of the robotic system must program the robot to follow an emergency strategy that enables it to avoid any contact with a probable obstacle anywhere anytime within the working space of the robot. For mobile robots this task is relatively easier to accomplish since this type of robots have the flexibility to change their routes and take alternatives that are free of obstacles. For fixed robotic arm manipulators the situation is much more complex. In this paper we are only concerned with obstacle avoidance techniques and present a real-time obstacle avoidance method for fixed robotic arms that combines the benefits of both global and local techniques in that it can be used for both static and dynamic environments with a reduced computational effort.
Design and implementation of a single-side flat synchronous linear motor model
Authors: Ahmed Raghda’a , Mahel Mohammed Farag , Abdul-Kareem Mohammed Jamal
Published: March 2020

In recent decades, the demand for a linear motor has increased in various applications, due to its ability to develop a linear motion directly. One of the significant problems facing the operation of the linear motor is the presence of force ripple caused by the irregular magnetic field of the permanent magnets. Accordingly, a developed single-side permanent magnet synchronous flat linear motor (PMSLM) model has been designed based on minimizing its force ripple produced. A Maxwell ANSYS simulation is performed to study and enhance the dynamic characteristics and performance of the model and then verifying it with experimental measurements. Multi-objective optimization had been achieved through reducing the size of permanent magnets and reaction rail at specific rates with maintaining the required thrust and reducing the cogging force. The results of the improved model design showed that the maximum value of the force ripple is reduced by about 81.13% compared with the primary model at a smaller ripple coefficient of 0.22%. The comparison between the experimental measurements and numerical analysis showed a good agreement and accuracy of the analytical results.
Adaptive Control Using NARMA-L2 Model and Electric Circuit for Condenser of Thermal Power Plant
Authors: Salim Anead Hosham , Faisal Sultan Khalid , Jawad Raheel
Published: March 2020

Design and implantation electric circuit for enhancement performance of steam power plant and artificial neural networks technique used to control of condenser. Artificial neural network has been applied to control of the important variables of condenser in Al–Dura power plant in Baghdad such as pressure, temperature. in this study, applied Simulink model in Matlab program (v 2014 a) by using artificial neural network toolbox. the model of condenser of neural network by using NARMA to generated data and train network and using back propagation algorithm for training neural network. The method of control by ANN is off line. the electric circuit of pressure sensor and temperature sensor consist of transformer, dc bridge and voltage regulator. Experimental data of actual power plant obtained from al-dura power plant. comparing results of modelling neural network and electric circuit with experimental data of actual power plant. the results shown the maximum deviation between the ANN and electric circuit with experimental data is less than 4%. artificial neural network can be used in many industrial and engineering application.
The hybrid Photovoltaic-Thermal double-pass solar system for drying applications
Authors: Jadallah Abdullatif A. , Alsaadi Mohammed K. , Hussien Saifalddeen A.
Published: March 2020

In this paper, is devoted to evaluating the performance of the double-pass hybrid Photovoltaic-Thermal (PVT) solar system proposed for drying purposes theoretically and experimentally as well as the system is designed, fabricate and modeled in order to simulate the productivity of this system. The hot air extracted from the PVT collector can be used as a heat source for the drying application. The critical parameter such as temperature distribution, useful heat gain, electrical power, and thermal efficiency are computed using MATLAB 2015b program built for this purpose. Results show that the higher output fluid temperature was 63°C at a lesser mass flow rate which 0.017 kg/s and the maximum efficiencies of electrical, thermal and overall at a higher mass flow rate which reached 12.65%, 56.73%, and 85% respectively at mass flow rate 0.031 kg/s. In addition, the optimum electrical power and thermal energy reached 50.57 W and 389.37 W at 0.031 kg/s.
Photovoltaic Thermal (PV/T) Collector Performance Evaluation as Electricity Generation and Hot Air Supplier For Partially Covered with PV Modules
Authors: Mohammed Jalil Jalal , Abdulqader Hussein Ahmed , Jabbar Faisal Anwar
Published: March 2020

This study experienced the performance of air biased PV/T collector partially covered with glass at various values of irradiance (400, 600, 800, 1000) W/m
2 and constant ambient temperature. A three various configurations have been demonstrated in this work, case A (glass at inlet portion), case B (glass at mid portion) and case C (glass at outlet portion). The investigation has been performed in term of outlet air temperature and electrical power. A numerical model was developed via using the computational fluid dynamic (CFD) program. 3D steady state, turbulent forced convection model is utilized to solve Navier Stokes and energy equations of air flowing inside the duct. The results compared with the experimental measurements that carried out from indoor conditions using solar simulator, a strong agreement has been achieved between experimental and numerical outcomes. It has been observed that case C ( glass at outlet portion) is more favorable in electrical and thermal gain, which generates 44.3°C hot air and 26.6 W electric power, while the maximum outlet air temperature and electric power reach 39 °C, 25.4 W and 43 °C, 21.05 W for configurations A and B respectively. Furthermore, the analysis of PV/T system concluded that the PV/T system should be operate at moderate air flowrate (0.013 kg/s) which is the specific or optimum flowrate.
Impacts of non-homogeneous nanofluid approach and orientation angle on convection heat transfer within a 3D wavy cavity
Authors: Alsabery Ammar I. , Ayaal Adel H. , Hashim Ishak
Published: March 2020

Steady laminar natural convection and heat transfer inside a tilted 3D wavy cavity filled by water-Al2O3 nanofluid does examined numerically by applying the finite element technique. An isothermal curved heater is located at the right surface of the chamber while the left surface remains in a steady cold temperature. The top and bottom horizontal surfaces (top and bottom) are held adiabatic. The governing equations are formulated in the non-dimensional model using the two-component non-homogeneous equilibrium model through transporting phenomena in nanofluids connecting among the influences of Brownian diffusion and thermophoresis. The results of the dimensionless buoyancy-driven parameter, inclination angle, nanoparticle volume fraction and number of undulations were examined. It is shown that the inclination angle, the wavy shape of the surface plus the features of nanofluid are outstanding control parameters to the rate of the heat transfer and the distribution of the fluid flow.
Utilizing the Computation Intelligence Technique for Boiler Pressure Controlling
Authors: Anead Hosham S. , Sultan Khalid F. , Ahmed Ayat
Published: March 2020

This paper aims to detect a damage in boiler of steam plant by using intelligence technique to improve the boiler performance. Experimental information is obtain by use an industrial boiler operating at AL-Dura power plant. This manuscript presents is to compare intelligence technique for boiler of steam power plant PID, ANFIS, PSO technique . Designing various pressure controllers to keep the boiler operating in normal conditions and enhance the efficiency. Those parameters are regulated through building a model and implementing in MATLAB, based on steam power plant requisite and the aims of the control. Results have shown that the PSO algorithm is optimal controlled and offers superior power plant performance from the PID controller. PSO, ANFIS and PID were implemented in AL–Dora power plant in Baghdad. Those techniques have been extensively utilized in numerous industry applications.
INFLUENCE OF ROUGHNESS PARAMETERS ON THE HARDENING OF CAST STEEL PLATES
Authors: Lopatin A.A. , Obeid Hassoun Enaam , Abdulaziz Abrahem Hussain , Eremeeva Ch. F. , Gabdullina R.A.
Published: March 2020

This paper presents the experimental and numerical analysis of the effect of roughness parameters on the hardening of a 148 mm x 148 mm cast steel plate. The temperature distribution on the plate surface was measured at various points, and the infabstractrared (IR) camera was used to capture infrared images during the cooling process. In this study, the temperature distribution on the plate surface was evaluated at each pixel image, and the data was collected and recorded using the Therma CAM researcher 2001 software. The results show that the cooling rates on the smooth and rough sides were significantly high at 500 C. Also, it has been found that the total amount of energy is constant over the entire thickness of the sample
Experimental and Modelling the Combined Measurements Technique for Microwave Absorbing Coatings Testing with Finite Difference Time Domain Method
Authors: Hassan Abdulkadhim A. , Saadie Janan H.
Published: March 2020

Because of the structure property of radar absorbing coatings, using of the existing methods for testing these materials is quite difficult. In this paper, a combined-measurement technique was proposed for broadband characterization of microwave absorbing coatings using flanged rectangular waveguide sensor. The technique combines both frequency sweep reflections measurement and two-layer method to provide two different test conditions of the needed reflection coefficients necessary to extract both complex permittivity and complex permeability over a given frequency range. The first set of reflection coefficients is obtained by directly placing the sensor alongside the coating material and performing broadband measurement using frequency sweep over the selected frequency points of frequency range. The same procedure is applied on a combination of known material followed by the test material to measure the second set of the respective reflection coefficients. Finite Difference Time Domain (FDTD) method was employed to numerically calculate the sensor reflection coefficient and analyse the influence of the sensor geometry and coating material thickness on measurement accuracy. The measurement results of both complex permittivity and permeability for various samples of microwave absorbing coatings were agreed well with reference data. Simple interpolation approximation was introduced in their extraction process from multiple reflection coefficient data since they are frequency dependent parameters . The proposed technique speeds up and simplifies coating materials testing, while it decreases the error due to repeatability of measurement.
Performance Analysis of Linear Topology Wireless Sensor Network in Oil and Gas Industry
Authors: Lee M.Y. , Azman A.S. , Subramaniam S.K. , Feroz F.S.
Published: March 2020

Oil and gas industry is one of the largest corporations in the world. The process and machinery involved for the petroleum product to be extracted, refined and transported are usually critical and complex. Hence, it is crucial to have a stable and reliable system to control, monitor and manage the security the industrial assets. Since Wireless Sensor Network (WSN) can sense, process and communicate, it is one of the best and popular solution to the problem existed in the oil and gas industry. In this paper, a detailed performance analysis of AODV, DSDV and FIXRT with 32 and 128 packet size is presented by using linear topology in accordance with IEEE 802.11 standards by using ns2.35 simulator. The results showed that FIXRT protocol increases the overall performance of the network by almost 30%.
Albuminuria, Kidney Function, and Cancer Risk in the Community
Authors: Mok Yejin , Ballew Shoshana H , Sang Yingying , Coresh Josef , Joshu Corinne E , Platz Elizabeth A , Matsushita Kunihiro
Published: March 2020

Few studies have comprehensively investigated the association of 2 key kidney disease measures, estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (ACR), with cancer incidence. In 8,935 participants at the baseline (1996–1998) from the Atherosclerosis Risk in Communities study, we quantified the associations of eGFR (based on creatinine and cystatin C) and ACR with cancer risk using Cox regression models adjusted for potential confounders. Due to changing guidelines for prostate cancer screening during the follow-up period, we investigated overall cancer, overall nonprostate cancer, and site-specific cancer. During a median follow-up of 14.7 years, 2,030 incident cancer cases occurred. In demographically adjusted models, low eGFR and high ACR were associated with cancer incidence (both overall and overall nonprostate cancer). These associations were attenuated after adjusting for other shared risk factors, with a significant association remaining only for ACR (≥103 compared with 5 mg/g) and overall nonprostate cancer. For site-specific cancer, only high ACR showed a significant association with lung and urinary tract cancers. Of these, the association between ACR and lung cancer appeared most robust in several sensitivity analyses. Kidney disease measures, particularly high ACR, were independently associated with cancer risk. The association between ACR and lung cancer was uniquely robust, warranting future studies to explore potential mechanisms.
Full spectra coloration and condition-dependent signaling in a skin-based carotenoid sexual ornament
Authors: Harris Sarah , Kervinen Matti , Lebigre Christophe , Pike Thomas W , Soulsbury Carl D
Published: March 2020

Carotenoid-based traits commonly act as condition-dependent signals of quality to both males and females. Such colors are typically quantified using summary metrics (e.g., redness) derived by partitioning measured reflectance spectra into blocks. However, perceived coloration is a product of the whole spectrum. Recently, new methods have quantified a range of environmental factors and their impact on reflection data at narrow wavebands across the whole spectrum. Using this approach, we modeled the reflectance of red integumentary eye combs displayed by male black grouse (Lyrurus tetrix) as a function of ornament size and variables related to male quality. We investigated the strength and direction of effect sizes of variables at each waveband. The strongest effect on the spectra came from eye comb size, with a negative effect in the red part of the spectrum and a positive effect in ultraviolet reflectance. Plasma carotenoid concentration and body mass were also related to reflectance variance in differing directions across the entire spectra. Comparisons of yearlings and adults showed that the effects were similar but stronger on adult reflectance spectra. These findings suggest that reflectance in different parts of the spectrum is indicative of differing components of quality. This method also allows a more accurate understanding of how biologically relevant variables may interact to produce perceived coloration and multicomponent signals and where the strongest biological effects are found.
A statistical framework for predicting critical regions of p53-dependent enhancers
Authors: Niu Xiaohui , Deng Kaixuan , Liu Lifen , Yang Kun , Hu Xuehai
Published: March 2020

P53 is the ‘guardian of the genome’ and is responsible for regulating cell cycle and apoptosis. The genomic p53 binding regions, where activating transcriptional factors and cofactors like p300 simultaneously bind, are called ‘p53-dependent enhancers’, which play an important role in tumorigenesis. Current experimental assays generally provide a broad peak of each enhancer element, leaving our knowledge about critical enhancer regions (CERs) limited. Under the inspiration of enhancer dissection by CRISPR-Cas9 screen library on genome-wide p53 binding sites, here we introduce a statistical framework called ‘Computational CRISPR Strategy’ (CCS), to predict whether a given DNA fragment will be a p53-dependent CER by employing 7-mer as feature extractions along with random forest as the regressor. When training on a p53 CRISPR enhancer dataset, CCS not only accurately fitted the top-ranked enriched single guide RNAs (sgRNAs) but also successfully reproduced two known CERs that were validated by experiments. When applying it to an independent testing dataset on a tilling of a 2K-b genomic region of CRISPR-deCDKN1A-Lib, the trained model shows great generalizability by identifying a CER containing five top-ranked sgRNAs. A feature importance analysis further indicates that top-ranked 7-mers are mapped onto informative TF motifs including POU5F1 and SOX5, which are differentially enriched in p53-dependent CERs and are potential factors to make a general p53 binding site to form a p53-dependent CER, providing the interpretability of the trained model. Our results demonstrate that CCS is an alternative way of the CRISPR experiment to screen the genome for mapping p53-dependent CERs.
How much did pottery workers know about classical art and civilisation?
Authors: Hall Edith
Published: March 2020

The voices of pottery workers across the British Isles during the heyday of the taste for classically themed ceramics are almost silent to us, since so few left memoirs or diaries. But other sources cumulatively build up a picture of skilled male, female, and child workers familiar with multifarious ancient artefacts and books visually reproducing them. At Etruria and Herculaneum, workers were encouraged to see themselves as participants in the rebirth of the ancient ceramic arts; they were trained in painstaking reproduction of details not only from ancient vases but from ancient gems, intaglios, ivories, coins, bas-reliefs, frescoes, friezes, statues, and sarcophagi. They were familiar with the stories of a substantial number of ancient mythical and historical figures, and the different aesthetic conventions of classical Athenian, Hellenistic, and Roman art. Some were even able to study antiquity at institutions of adult education, and had access to well-stocked workers’ libraries.
Position-wise binding preference is important for miRNA target site prediction
Authors: Talukder Amlan , Li Xiaoman , Hu Haiyan
Published: March 2020

Motivation

It is a fundamental task to identify microRNAs (miRNAs) targets and accurately locate their target sites. Genome-scale experiments for miRNA target site detection are still costly. The prediction accuracies of existing computational algorithms and tools are often not up to the expectation due to a large number of false positives. One major obstacle to achieve a higher accuracy is the lack of knowledge of the target binding features of miRNAs. The published high-throughput experimental data provide an opportunity to analyze position-wise preference of miRNAs in terms of target binding, which can be an important feature in miRNA target prediction algorithms.

Results

We developed a Markov model to characterize position-wise pairing patterns of miRNA–target interactions. We further integrated this model as a scoring method and developed a dynamic programming (DP) algorithm, MDPS (Markov model-scored Dynamic Programming algorithm for miRNA target site Selection) that can screen putative target sites of miRNA-target binding. The MDPS algorithm thus can take into account both the dependency of neighboring pairing positions and the global pairing information. Based on the trained Markov models from both miRNA-specific and general datasets, we discovered that the position-wise binding information specific to a given miRNA would benefit its target prediction. We also found that miRNAs maintain region-wise similarity in their target binding patterns. Combining MDPS with existing methods significantly improves their precision while only slightly reduces their recall. Therefore, position-wise pairing patterns have the promise to improve target prediction if incorporated into existing software tools.

Availability and implementation

The source code and tool to calculate MDPS score is available at http://hulab.ucf.edu/research/projects/MDPS/index.html.

Supplementary information

Supplementary data are available at Bioinformatics online.
Sequence comparisons of cytochrome P450 aromatases from Australian animals predict differences in enzymatic activity and/or efficiency†
Authors: Fatima Anam , Holien Jessica K , Tiwari Chandni , Parker Michael W , Rodgers Raymond J , Martin Lisandra L
Published: March 2020

Aromatase (P450arom, CYP19A1) is the terminal enzyme in the synthesis of the steroid hormone family of estrogens. Not surprisingly, this enzyme has structural similarities between the limited number of species studied thus far. This study examined the structure of aromatases from four diverse Australian species including a marsupial (tammar wallaby; Macropus eugenii), monotreme (platypus; Ornithorhynchus anatinus), ratite (emu; Dromaius novaehollandiae) and lizard (bearded dragon; Pogona vitticeps). We successfully built homology models for each species, using the only crystallographically determined structure available, human aromatase. The amino acid sequences showed high amino acid sequence identity to the human aromatase: wallaby 81%, platypus 73%, emu 75% and bearded dragon at 74%. The overall structure was highly conserved among the five species, although there were non-secondary structures (loops and bends) that were variable and flexible that may result in some differences in catalytic activity. At the N-terminal regions, there were deletions and variations that suggest that functional distinctions may be found. We found that the active sites of all these proteins were identical, except for a slight variation in the emu. The electrostatic potential across the surfaces of these aromatases highlighted likely variations to the protein-protein interactions of these enzymes with both redox partner cytochrome P450 reductase and possibly homodimerization in the case of the platypus, which has been postulated for the human aromatase enzyme. Given the high natural selection pressures on reproductive strategies, the relatively high degree of conservation of aromatase sequence and structure across species suggests that there is biochemically very little scope for changes to have evolved without the loss of enzyme activity.
Genetic Contributions to Multivariate Data-Driven Brain Networks Constructed via Source-Based Morphometry
Authors: Rodrigue Amanda L , Alexander-Bloch Aaron F , Knowles Emma E M , Mathias Samuel R , Mollon Josephine , Koenis Marinka M G , Perrone-Bizzozero Nora I , Almasy Laura , Turner Jessica A , Calhoun Vince D , Glahn David C
Published: March 2020

Identifying genetic factors underlying neuroanatomical variation has been difficult. Traditional methods have used brain regions from predetermined parcellation schemes as phenotypes for genetic analyses, although these parcellations often do not reflect brain function and/or do not account for covariance between regions. We proposed that network-based phenotypes derived via source-based morphometry (SBM) may provide additional insight into the genetic architecture of neuroanatomy given its data-driven approach and consideration of covariance between voxels. We found that anatomical SBM networks constructed on ~ 20 000 individuals from the UK Biobank were heritable and shared functionally meaningful genetic overlap with each other. We additionally identified 27 unique genetic loci that contributed to one or more SBM networks. Both GWA and genetic correlation results indicated complex patterns of pleiotropy and polygenicity similar to other complex traits. Lastly, we found genetic overlap between a network related to the default mode and schizophrenia, a disorder commonly associated with neuroanatomic alterations.
Susceptibility to Hepatitis A Virus Infection in the United States, 2007–2016
Authors: Yin Shaoman , Barker Laurie , Ly Kathleen N , Kilmer Greta , Foster Monique A , Drobeniuc Jan , Jiles Ruth B
Published: March 2020

Background

Despite national immunization efforts, including universal childhood hepatitis A (HepA) vaccination recommendations in 2006, hepatitis A virus (HAV)–associated outbreaks have increased in the United States. Unvaccinated or previously uninfected persons are susceptible to HAV infection, yet the susceptibility in the US population is not well known.

Methods

Using National Health and Nutrition Examination Survey 2007–2016 data, we estimated HAV susceptibility prevalence (total HAV antibody negative) among persons aged ≥2 years. Among US-born adults aged ≥20 years, we examined prevalence, predictors, and age-adjusted trends of HAV susceptibility by sociodemographic characteristics. We assessed HAV susceptibility and self-reported nonvaccination to HepA among risk groups and the “immunization cohort” (those born in or after 2004).

Results

Among US-born adults aged ≥20 years, HAV susceptibility prevalence was 74.1% (95% confidence interval, 72.9–75.3%) during 2007–2016. Predictors of HAV susceptibility were age group 30–49 years, non-Hispanic white/black, 130% above the poverty level, and no health insurance. Prevalences of HAV susceptibility and nonvaccination to HepA, respectively, were 72.9% and 73.1% among persons who reported injection drug use, 67.5% and 65.2% among men who had sex with men, 55.2% and 75.1% among persons with hepatitis B or hepatitis C, and 22.6% and 25.9% among the immunization cohort. Susceptibility and nonvaccination decreased over time among the immunization cohort but remained stable among risk groups.

Conclusions

During 2007–2016, approximately three-fourths of US-born adults remained HAV susceptible. Enhanced vaccination efforts are critically needed, particularly targeting adults at highest risk for HAV infection, to mitigate the current outbreaks.
Phạm Duy Khiêm, classical reception, and colonial subversion in early 20th century Vietnam and France
Authors: Nguyen Kelly
Published: March 2020

The tradition of the Vietnamese reception of classical literature has not yet been examined, and this article is the first to venture into this intersection between Classics and Vietnamese studies. In this article, I focus on Phạm Duy Khiêm (1908–74) and his use of Classics to translate and mediate his Vietnamese heritage to his French audience. Phạm lived during a particularly turbulent time in Vietnamese history: he experienced Vietnam as a French protectorate called Annam, he witnessed his compatriots defy French rule and win independence for Vietnam, and he saw the civil war that challenged that new independence. Throughout these changing political contexts, Phạm navigated the politics of polarity that separated the colonizer from the colonized as he struggled to make sense of these supposedly irreconcilable differences between the two, which contested his own intercultural identity. In this article, I argue that Phạm used his classical education and its cultural capital not only to explain Vietnamese culture to his French audience, but also to elevate it as equal, and perhaps even superior, to that of the French and their supposed classical inheritance.
Educational Transitions and Educational Inequality: A Multiple Pathways Sequential Logit Model Analysis of Finnish Birth Cohorts 1960–1985
Authors: Härkönen Juho , Sirniö Outi
Published: March 2020

We developed a multiple pathways sequential logit model for analysing social background inequality in completed education and applied it to analyse educational inequality in Finland (birth cohorts 1960–1985). Our model builds on the sequential logit model for educational transitions, originally presented by Robert D. Mare and later extended by Maarten Buis, which disaggregates inequality in completed education into the weighted sum of inequalities in the transitions leading to it. Although the educational transitions framework is popular among educational stratification researchers, its applications have almost exclusively focused on analysing inequalities in separate educational transitions. Buis presented a unifying model of inequalities in educational transitions and completed education, which gives a substantive interpretation to the weights that link them. We applied this to an educational system in which the same educational outcomes can be reached through multiple pathways. Our analysis of Finnish register data shows that intergenerational educational persistence increased, particularly among women. The main reasons are increased inequality in academic upper-secondary (gymnasium) completion and gymnasium expansion that increased the weight of this transition as well as of the transition to university. We discuss the integration of structural and allocative mechanisms in educational stratification research.
Impacts of copper and lead exposure on prokaryotic communities from contaminated contrasted coastal seawaters: the influence of previous metal exposure
Authors: Coclet Clément , Garnier Cédric , Durrieu Gaël , D'onofrio Sébastien , Layglon Nicolas , Briand Jean-François , Misson Benjamin
Published: March 2020

Our understanding of environmental factors controlling prokaryotic community is largely hampered by the large environmental variability across spatial scales (e.g. trace metal contamination, nutrient enrichment and physicochemical variations) and the broad diversity of bacterial pre-exposure to environmental factors. In this article, we investigated the specific influence of copper (Cu) and lead (Pb) on prokaryotic communities from the uncontaminated site, using mesocosm experiments. In addition, we studied how pre-exposure (i.e. life history) affects communities, with reference to previous metal exposure on the response of three prokaryotic communities to similar Cu exposition. This study showed a stronger influence of Cu contamination than Pb contamination on prokaryotic diversity and structure. We identified 12 and 34 bacterial families and genera, respectively, contributing to the significant differences observed in community structure between control and spiked conditions. Taken altogether, our results point toward a combination of direct negative responses to Cu contamination and indirect responses mediated by interaction with phytoplankton. These identified responses were largely conditioned by the previous exposure of community to contaminants.