bluuebunny/crossref_metadata_2025 huggingface dataset:
Effectiveness of Seismically Resistant Braced Frames to Blast Loading
Authors: Kapoor Akshay , Setia Saraswati
Published: December 2020

The increment in the tally of terrorist radicalisation from the past time has exhibited that the consequence of blast loads on structures is a crucial matter that should be taken into cogitation. This paper considers the effect of blast load on seismically designed framing systems namely Moment Resisting Frame (MRF), Concentric Braced Frame (CBF), Eccentric Braced Frame (EBF) and Buckling Restraint Braced Frame (BRBF). The bracings are one of the efficient lateral load resisting systems and their behaviour is observed under the blast loading. The burst load is estimated to be an unconfined surface burst explosion on front face of the structure. Comparative analysis of storey displacement among different framing systems is performed. Failure of members is studied through the analysis of plastic hinge formation. The results indicate that braced frames perform better when exposed to such kind of impact load. Buckling Restraint brace (BRB) exhibited higher level of resistance to blast loading due to its ability to yield in both compression and tension.
Shear Mode Damper Testing Using Flake Shape Based Magnetorheological Fluids
Authors: Patel D. M. , Bhatt D. V. , Upadhyay R. V.
Published: December 2020

Use of anisotropic iron particles in the magnetorheological (MR) fluid having a high yield stress is a challenge as it increases the viscosity of the fluid in off-state. In this clause, a novel flake shaped iron powder based MR fluid with high yield stress is synthesized and used in shear mode MR damper (SMMD). MR damper design is optimized using fluid properties and Bingham model. Damping performance of newly synthesized MR fluid damper is at par with the available friction based damper used in front loaded washing machine. The unique feature of this design is minimal volume of the fluid (1.5 ml) required to achieve damping force of 50N. Effect of different volume percentage of particles in MR fluid is evaluated in terms of damping force. Effect of testing parameters like displacement and frequency of excitation on damping force was evaluated. Effect of settling of particle on damper performance is discussed in this work. It shows that the flakes shaped-based MR fluid show better stability against gravity. The smaller quantity of present flake shaped-based MR fluid will reduce the cost of shear mode damper.
Surface Characteristics Enhancement of Biocompatible Mg Alloy AZ31B by Cryogenic Milling
Authors: Chhetri Subham , Tariq Mohammad , Mohapatra Stephen Dilip , Vikali Sumi V , Zhimomi Alomi P , Davis Rahul , Singh Abhishek
Published: December 2020

The mechanical, physical and chemical properties of Magnesium alloys have undoubtedly proven compatible and efficient for their aid in biomedical sector. Magnesium tends to corrode rapidly in in-vivo environment limiting its efficiency and life expectancy as a biomedical implant. This has led to the study and research of the properties of these excellent materials in order to increase its corrosion resistivity property. In the recent years through thorough research and study it has been proven that cryogenic machining is an efficient technique for surface integrity improvements which plays a vital role in the increment of corrosion resistivity of a material. This work in particular is one of the studies in which the milling operation is carried out on a CNC milling machine on the commercially available AZ31B Magnesium alloy by a cemented carbide tool under two different milling environments namely wet and cryogenic. Different machining factors were opted and comparative investigation was conducted between the two machining conditions. The post machined results were further compared for minimum surface roughness. The comparative analysis presented a better surface finish in case of cryogenic milling than wet milling.
Reduction of positional error in a path of a 2 DOF serial planar manipulator
Authors: Tatte R N , Thorat H T , Deosant P V
Published: December 2020

Tracing a path is one of the major applications of a robotic arm. In this paper, a 2 DOF serial planar manipulator which traces the desired path is discussed. Quite often the path is defined by accuracy points lying on it. To trace these points, joints of links of the manipulator are required to be given as a coordinated inputs θ
1 and θ
2 (input angles of two links). This path is traced with a desired speed indicated by the time at which the accuracy points are reached.

In open-loop control, this is achieved by giving time, voltage/current input to driving motors. This path is determined based on the torque, acceleration, velocity of the linkages and individual joints. Hence the relationship between time and joint angles is necessary. When joint angles θ
1 and θ
2 are interpolated between two accuracy points, precise coordinated motion is not possible. Some deviation from the desired path will occur. This is the positional error for tracing the path. Here, analysis has been done to find the effect of degree of interpolation on the positional error.
Bending analysis of a sandwich plate with elliptical/circular cutout
Authors: Lal Achchhe , Sutaria B.M , Kumar Rahul
Published: December 2020

Applications of sandwich plate as light weight structural member rapidly increased since last two decades because of its higher flexural rigidity to weight ratio. From aerospace vehicle to racing car, from giant submarine to small boat, from bicycle to high speed train all these weight sensitive areas have various parts made up by composite sandwich plates. Sometimes these members have hole of various shape for access of internal parts, lighting, ventilation etc. due to presence of these geometrical discontinuities in the form of hole, the structure gets more vulnerable to failure. During functioning, these parts usually acted upon by transverse force which may cause large deflection in the member or failure of the structure. Therefore, proper analysis of these structural member is desired for efficient and safe design. In the present work bending analysis of sandwich plate with elliptical and circular hole is carried out using finite element based first order shear deformation theory. A MATLAB program is developed for the present analysis. The efficiency of the program is found good as present results shows good agreements with the already published results.
Post-buckling analysis of the shape memory polymer sandwich composite beam under dynamic temperature variation
Authors: Lal Achchhe , Markad Kanif
Published: December 2020

Post-buckling analysis of the shape memory polymer sandwich composite (SMPSC) beam under HSDT utilizing von Karman kinematics using FEM is performed in present analysis. The aim of the study is to develop a model which accurately perform the buckling analysis. The nondimensional critical buckling load (NCBL) evaluation under the action of inplane uniform load with different boundary conditions (BC), plate thickness ratio, under dynamic temperature variation for SMPSC. The study clearly reveled the differentiation between SMPC and SMPSC beam.
ABAQUS Implementation to Analyze the Stress Intensity Factor for Laminated Composite Plate
Authors: Lal Achchhe , Vaghela M. B.
Published: December 2020

The objective of this work is Abaqus implementation to analyze the effect of fibre orientation angle on stress intensity factor for Single Edge Notched (SEN) 3D laminate composite plate under tensile loading by various cases. The Abaqus software is used to analyze the various problems through the extended finite element method (XFEM). The effects of various fibre orientation angles on Sress Intensity Factor (SIF), Von Misses stress and displacement are also investigated. The presented work would be useful for enhancing the use of Abaqus software to analyze the composite structure with crack and other discontinuities under various conditions.
Finite element analysis of AISI 8620 alloy spur gear hot forging
Authors: Kanani J B , Lalwani D I
Published: December 2020

Among all manufacturing processes, a forging process has a remarkable position in which parts with desired mechanical properties and minimum wastage of material can be produced. Despite of mentioned advantages, forging process has few drawbacks such as high tonnage capacity machineries, expensive dies, high initial investment and die failure. The overall cost of the forging process directly depends upon the required forging load, ejection load and dies arrangements. In this paper, Finite Element Analysis (FEA) of a spur gear forging process made of low carbon alloy steel (AISI 8620) is carried out. Two load reduction methods (elastically attached die and relief hole) are simultaneously used and analyzed using DEFORM- 3D software. The required forging load is compared between non-elastic die arrangements and elastic die arrangements with the relief hole. Velocity distribution is also discussed at nine different locations.
Effect of rotational speed on structural and optical properties of spin coated SnO thin films
Authors: Priyanka L , Hymavathi B , Kumar B Rajesh
Published: December 2020

Tin monoxide films were synthesized by sol-gel process followed by spin coating at the spinning speeds from 1000 to 3000 rpm. X-ray diffraction profiles of the films exhibits amorphous nature. Surface morphological and elemental confirmation of SnO films were studied by scanning electron microscope and energy dispersive of X-ray spectroscopy. The optical transmittance of the films had an increment from 60 to 72% with the increase of spinning speed from 1000 to 3000 rpm. The band gap of SnO thin films varied from 2.96 to 3.52 eV with an increment in rotational speed due to Burstein-Moss (B-M) effect. The estimated particle size from the optical absorbance spectra using effective mass approximation method is decreased from 23.6 nm to 11.6 nm with an increment in the spin speed from 1000 to 3000 rpm.
Heat Transfer Characteristics of Water Cooled Minichannel Heat Sink Using Different Fluid Flow Geometries
Authors: Makam Jugal Shrinivas , Totla Nilesh Balkishanji
Published: December 2020

Efficient heat transfer for compact electronic components has become a major need in these days. For this purpose, we require a minichannel heat sink with a liquid cooling system that makes these requirements as possible. In this work, both analytical and CFD investigations have been carried out to calculate the heat transfer performance of a minichannel heat sink consisting of cross sections with three different shapes of a rectangular, trapezoidal and hexagonal in which working fluid is made to flow. The simulation is conducted with water as the working fluid for three different shapes with Reynolds number ranging from 200 to 1000 and analyzed numerically for the single-phase laminar flow with the boundary condition of constant heat flux. The channel dimensions and inlet velocity effects on the Nusselt number, pressure drop, and heat transfer coefficient are studied. The 3D steady-state, laminar flow, and governing equations of heat transfer are solved using the finite volume method by commercial ICEM-Fluent software.
Dynamic Analysis of Fixed-Fixed Beam Under Mechanical Shock Loads
Authors: Sharma G. , Mishra Abhishek , Selvaraj P.
Published: December 2020

Aerospace missions are very expensive and any carelessness may lead to mission failure. So, each component that should be installed in a launch vehicle and spacecraft essentially be designed and developed to ensure its reliability. In this paper, a beam made up of Al 6061 T6 material is modeled in the ANSYS 18.0 software and subject to a similar condition to the component of the launcher vehicle. Transient acceleration load having magnitude approximately equal to the amplitude of acceleration developed during pyrotechnic events is applied in X, Y and Z direction of the beam and response of the beam at different locations of the beam is calculated and based on the response acceleration time history a Shock Response Spectrum (SRS) is plotted for locations of interest on the beam. Furthermore, Response Spectrum Analysis is performed on the beam based on the SRS of pyroshock event, provided by the Laboratory for Electro-Optics Systems (LEOS), Indian Space Research Organization (ISRO).
Effect of Spindle Speed, Feed Rate and Cooling Medium on the Burr Structure of Aluminium through Milling
Authors: Sharma Aman , Dwivedi Vijay Kumar
Published: December 2020

The burr is formed during milling, when the tool exits the work piece in any machining operation. The burr formation on a milling machine with the use of end mill cutter with different speed and different cooling mediums like air, water, and cutting fluid are discusses. The tool used for the machining operation is an end mill cutter tool. This work is taken up to examine the effect of different speeds and different cooling mediums on burr formation in the milling operation of aluminium in a dry and wet atmosphere. Results are found on the exit edge of the work piece, found during the milling operation. This paper manages with the aspects that influence the formation of burr and type of burr formed while doing experiment. The parameters considered are, the maximum length of stroke, drive speed (step cone pulley), range of speed arrangement groove and the selection of a cooling medium. The drive speed of the milling machine was measuring by Tachometer in all drive stages. The pictures of produced burrs were taken with the support of a digital microscope and digital camera.
Effect of Two Stages Artificial Ageing on Microstructure and Mechanical Behavior of Lm 25 Aluminium Alloy
Authors: Bhaskara Raju VVS , Sevanam Sambi Reddy , Varadala Ananda Babu , Chitturi Suresh
Published: December 2020

In the present investigation the influence of two stages artificial ageing, 1st stage at 160°C followed by 2nd stage at 140°C on microstructure and mechanical properties of LM 25 alloy was studied. It is observed that the microstructure changed under the influence of two stages ageing. It is also observed that the decrease in ageing temperature in the second stage, increases mechanical properties of the alloy. The tensile strength of the alloy in single stage ageing at 160°C is studied and compared with two stages ageing.
Stabilization of Expansive Soil by using Jute Fiber
Authors: Lal Dharmesh , Reddy Pravalika , Kumar R. Sandeep , Rao V. Govardhan
Published: December 2020

The instability of structure lies mainly in the properties of soil under which it is constructed. For instance, if the soil is having weak engineering properties, there are chances of crack formation and settlement. One of the major problematic soils of this type are the Black cotton soils which are mainly classified as expansive soils. They are obviously a hindrance to the strength and stability of structures. The present study deals with the improvement of soil characteristics with the addition of Jute fiber sheet. A series of Triaxial and CBR tests were done on normal soil and Jute fiber reinforced one. The observed values indicate a significant contribution of strength improvement when fiber sheets were added.
A Review of Ultrasonic Assisted Electrolytic In-Process Dressing (UA-ELID)
Authors: Awati Dhanesh B , Chanmanwar Rahul M
Published: December 2020

This paper presents previous research work of researchers on electrolytic in-process dressing and its ultrasonic-assisted system variant. This paper also contains information about the ELID system and applications of ultrasonic-assisted ELID. This technique enables continuous dressing of wheels made using metallic bond in the grinding process itself while retaining sharp grits from the super abrasive wheels. An ultrasonic-assisted setup requires an ultrasonic power generator, piezoelectric transducer (PZT), horn assembly. An ultrasonic generator generates ultrasonic pulses, which are supplied to the piezoelectric transducer. The piezoelectric transducer then converts electrical energy to mechanical energy and vibrates either in longitudinal mode or in transverse mode. The horn system then amplifies these vibrations, and amplified vibration is supplied to the grinding tool. The relevance of research papers referred to regarding setup development of ultrasonic-assisted electrolytic in-process dressing, effect of process parameters and modeling of the ultrasonic-assisted ELID process is described in this paper.
Superhard Alloys: A Review of Empirical Modeling and Computational Strategies
Authors: Chandramouli Ch. , Venkatesh B. , Hussain M.Manzoor
Published: December 2020

Superhard alloys has gained major research interest in recent past as it represents an effort to create man made alloys with hardness on par with the hardest substance available to us i.e. a naturally occurring diamond. They are virtually incompressible solids with high electron density and high bond covalency. Present paper aims to review the empirical methods and computational techniques developed by employing them using published literature, in order to attain a better understanding of complexities involved in synthesis of such compounds as a first step towards developing a new superhard metallurgical composition with similar mechanical attributes.
Design Failure Mode and Effect Analysis – Case Study
Authors: Nadaf Adila R. , Chanmanwar Rahul M.
Published: December 2020

Design-Failure mode and effect analysis (D-FMEA) is very important tool used in industries to detect failure during design stage. D-FMEA is a technique to find out causes of failure and their effects on the performance of a system(parts) during design phase. In this paper, the D-FMEA of critical components of designed automatic tilting mechanism trolley is carried out. The critical components of automatic tilting mechanism trolley are identified and analyzed by the D-FMEA tool. This paper provides risk priority number of components of trolley. The component with higher risk priority number has higher chances of failure. The risk priority number of critical components is reduced by incorporating corrective actions. This paper provides probable causes of failure, effects of failure and corrective actions to be undertaken during design phase of Automatic tilting mechanism trolley. The D-FMEA tools helps in reducing accidents.
Optimization of Helical Coil Tube Heat Exchanger: A Systematic Review
Authors: Rafi Shaik , Sivarajan Dr.C. , Mallikarjun.Ch Dr.
Published: December 2020

Helical coil heat exchanger is used in the food industries, air cooling industries etc.., due to its advantage of structural compact and high heat transfer coefficient. Many existing researches have been carried to improve the heat transfer efficiency and pressure drop. Mathematical model of the heat exchanger has been used to validate the performance of the heat exchanger. This paper involves in review the researches related to the optimization of helical coil tube heat exchanger. Some of the optimization methods such as Taguchi method, Genetic Algorithm (GA) and Multi-Objective Genetic Algorithm (MOGA) is used. From the analysis, Artificial Neural Network (ANN) and GA method has efficient performance in modelling and optimization of heat exchanger. Although, some methods involved in economic optimization of heat exchanger and these method has lower performance.
An Approach to Develop a Sustainable Preference Index for Self Compacting Concrete
Authors: Vanga Renuka
Published: December 2020

In construction industry, selecting a right material from the various alternatives is a critical task in contributing to promote sustainability. For evaluating performance of the material different conflicting attributes are considered which is very complex to make a decision. Focusing on that point, there is a necessity to implement an effective MCDM (Multi-Criteria Decision Making) technique in the building construction which helps the decision makers to choose the feasible sustainable material from the alternatives. The present study explores about the application of Preference Selection Index Method to develop an approach in selecting the optimum Supplementary Cementitious Materials which is called as Sustainable Preference Index (SPI). The foremost concern in the study is to optimize the use of SCM’s as a substitute for cement in Self Compacting Concrete (SCC) to assess sustainable performance by considering technical, environment and ecological traits. To illustrate an approach to develop a Sustainable Preference Index a case study has been considered by varying mineral admixtures such as Fly Ash and GGBS by 10%, 20%, 30%, 40% replacement of the mass of cement in SCC. From different available SCC mixes, the possible alternate in Self Compacting Concrete can be identified based on Sustainable Preference Index value which indicates sustainable performance. Among the FA and GGBS based Self Compacting Concrete mixes, 40GGBS-SCC has attained the highest Sustainable Preference Index (SPI) value. For 40GGBS-SCC the SPI value obtained is 0.891 whereas for 100OPC-SCC it is 0.740. From the SPI values attained, it can be concluded that 40GGBS-SCC is 20.4% more sustainable than the 100OPC-SCC.
An Emphasis of Geopolymer Concrete with Single Activator and Conventional Concrete with Recycled Aggregate and Data Analyzing using Artificial Neural Network
Authors: Rao G. Mallikarjuna , Kumar K. Satheesh , Poloju Kiran Kumar , Srinivasu Kota
Published: December 2020

The emphasis of concrete in the advancement of construction industry is essential. Due to the rapid increase in the development of infrastructure, there is a considerable demand for the construction materials. The construction materials drained gradually due to continue use in construction and there is a degree for the advancement of these development materials. Therefore, in this context, a rapid increase in the price of conventional construction materials and various governments have put restrictions on fine aggregates. In this circumstance, the investigation attempted to determine the appropriateness of the substitute materials in concrete development because these materials are eas ily available at very low cost as compared to conventional fine and coarse aggregates. The effect of recycled aggregates on the strength of conventional concrete and Geo-polymer concrete was studied. The natural aggregates are replaced by the crushed aggregates of intervals of 10%,20%, 30%, 40 %, and 50% in both geo-polymer and conventional concrete. The different strengths of 20MPa, 40MPa, and 60MPa werestudied in this research work. The conventional concrete cubes were cured in normal water and geopolymer concrete cubes cured in ambient room temperature. The coarse aggregates used were of size 20mm and 10mm sieved and the recycled aggregates contains a cement mortar attached to it. The outcomes show that a slight decline in the strength of conventional concrete and high strength found with 30% substitution of coarse aggregate and eventually the prediction of data was analyzed using Artificial Neural Network
Experimental Studies of Stellite-6 Hardfaced Layer on Ferrous Materials by Tig Surfacing Process
Authors: Chandra C Dinesh , Rushikesh B , Numan Mohammed , Venkatesh B
Published: December 2020

Hardfacing is the cheapest technique and it is the deposition of coatings of hard, wear resistant materials on a worn or new component that is subjected to wear, impact, high temperature, and oxidation. Weld hard facing is used to deposit thick layers of hard material by Tungsten Inert Gas (TIG) welding technique. This layer acts as a sacrificial layer at the point of impact and safeguards the base metal from wear out and corrosion. It is also used to fill the worn out part of a component there by increasing its durability and lifetime. A thick layer of stellite-6 of width 1mm is deposited on the base metals (i.e mild steel and EN-8) varying the weld currents as 120A, 140A, 160A. Vickers Hardness testing machine is used to measure the hardness of the hardfaced components and the variation of the hardness with varying weld current for both substrates. The specimens are subjected to oxidation at elevated temperature of 973K by muffle furnace for 5, 10, 15 hours duration and to study the oxidation rate with respect to different processing currents. The microstructural analysis is performed using optical microscopy on hardfaced samples. The aim of the paper is to study the effect in rate of oxidation, hardness, and microstructure with respect to varying parameters in stellite-6 hardfacing on ferrous materials.
Blue and bluish-white colors from the luminescent ZrO2 and ZrO2: Al3+ films prepared by the USP method
Authors: Martínez-Martínez R , Juárez-López G , García-Hipólito M , Díaz J J Bautista , Carmona Téllez Salvador , Aguilar-Frutis Miguel A , Alarcón Flores Gilberto , Falcony C
Published: December 2020

ZrO2 and ZrO2: Al3+(× at.%) films were deposited by ultrasonic spray pyrolysis process. Luminescent films were produced from Oxychloride Zirconium Octahydrate and Aluminium Chloride Hexahydrate as precursors. Measurements of photo and cathodoluminescence were carried out doing variations on deposition temperature and doping concentration (× at.% Al3+ions). With the increase in substrate temperature, an overall growth of photo-cathodoluminescence intensities was perceived. Furthermore, these films presented luminescence concentration quenching with hight Al doping concentration. Chromaticity coordinates indicated blue emission from host lattice (ZrO2 films) and cold-white emissions from ZrO2: Al3+(× at.%) films. Closest CIE coordinates to the perfect white emission were x = 0.303, y = 0.337. XRD patterns, measured with variations of substrate temperature, showed tetragonal phase of nano-zirconium oxide films. In addition, surface morphology characteristics for studied films are presented.
An easy-to-fabricate source measure unit for real-time DC and time-varying characterization of multi-terminal semiconductor devices
Authors: Das Avishek
Published: December 2020

A versatile Arduino based source measure unit (ASMU) is fabricated for measuring both the DC and low-frequency AC electrical characteristics of multi-terminal semiconductor devices. The ASMU system is capable of bidirectional voltage sourcing and current measurement in all four quadrants. The system is programmed with the LabVIEW environment for real-time data acquisition. The voltage bias and current measurement range are observed to be ±4.65 V and ±14.6 mA with an optimum resolution of 5 mV and 7.8125 μA, respectively. Both the two- and three-terminal passive and active devices can be characterized without changing any circuit configuration. The electronic and optoelectronic current-voltage, current-time, and transistor’s input/output characteristics can be performed only by customizing the programming codes. The performance of the ASMU system is found to be highly comparable with commercial measurement systems. The experimental results suggest its potential application in characterizing semiconductor devices with maintaining adequate precision, cost-effectiveness, and low-power consumption.
Differentiable programming for online training of a neural artificial viscosity function within a staggered grid Lagrangian hydrodynamics scheme
Authors: Melland Pake , Albright Jason , Urban Nathan M
Published: December 2020

Lagrangian methods to solve the inviscid Euler equations produce numerical oscillations near shock waves. A common approach to reducing these oscillations is to add artificial viscosity (AV) to the discrete equations. The AV term acts as a dissipative mechanism that attenuates oscillations by smearing the shock across a finite number of computational cells. However, AV introduces several control parameters that are not determined by the underlying physical model, and hence, in practice are tuned to the characteristics of a given problem. We seek to improve the standard quadratic-linear AV form by replacing it with a learned neural function that reduces oscillations relative to exact solutions of the Euler equations, resulting in a hybrid numerical-neural hydrodynamic solver. Because AV is an artificial construct that exists solely to improve the numerical properties of a hydrodynamic code, there is no offline ‘viscosity data’ against which a neural network can be trained before inserting into a numerical simulation, thus requiring online training. We achieve this via differentiable programming, i.e. end-to-end backpropagation or adjoint solution through both the neural and differential equation code, using automatic differentiation of the hybrid code in the Julia programming language to calculate the necessary loss function gradients. A novel offline pre-training step accelerates training by initializing the neural network to the default numerical AV scheme, which can be learned rapidly by space-filling sampling over the AV input space. We find that online training over early time steps of simulation is sufficient to learn a neural AV function that reduces numerical oscillations in long-term hydrodynamic shock simulations. These results offer an early proof-of-principle that online differentiable training of hybrid numerical schemes with novel neural network components can improve certain performance aspects existing in purely numerical schemes.
Characterization and Quantitation of Personal Exposures to Epoxy Paints in Construction Using a Combination of Novel Personal Samplers and Analytical Techniques: CIP-10MI, Liquid Chromatography–Tandem Mass Spectrometry and Ion Chromatography
Authors: Xue Yalong , Bello Anila , Bello Dhimiter
Published: December 2020

Epoxy resins are extremely versatile products that are widely used in construction for coatings, adhesives, primers, and sealers. Occupational exposures to epoxies cause allergic contact dermatitis, occupational asthma, hypersensitivity pneumonitis (epoxy-resin lung) and acute decline in lung function. Despite these health concerns, there is a striking paucity of quantitative exposure data to epoxy resins in construction. The lack of practical analytical methods and suitable personal samplers for monitoring of reactive two-component epoxide systems in real-world applications has been an unmet challenge for decades. Sampling and analysis methods for epoxies should be able to collect the paint aerosols efficiently, stop polymerization reactions at the time of sample collection, and subsequently provide detailed multispecies characterization of epoxides, as well as the total epoxide group (TEG) content of a sample, to properly document the chemical composition of exposures to epoxide paints.

In this work, we present the development and application of two new complementary quantitative analytical methods—liquid chromatography–tandem mass spectrometry with online ultraviolet detection and ion chromatography (IC)—for multispecies characterization of raw products, as well as inhalation and skin exposures to epoxy formulations in real-world construction applications. A novel personal sampler, CIP-10MI, was used for personal sampling of airborne epoxies. We report for the first time the results of personal inhalation and potential skin exposures to individual monomers and oligomers of bisphenol A diglycidyl ether (BADGE), as well as TEG, during metal structure coatings in construction; compare analytical results of the two analytical methods; and provide recommendations for method selection in future field studies. High inhalation and potential skin exposures to epoxies point to the need for interventions to reduce exposures among painters in construction.
The impact of the COVID-19 pandemic upon patients, staff, and on the future practices of percutaneous coronary intervention
Authors: Banning Adrian P. , Sabate Manel , Valgimigli Marco
Published: December 2020

The COVID pandemic in 2020 had unpredictable consequences on the presentation and management of patients with ischaemic heart disease. Subsequent to these initial responses the impact of the initial pandemic can be reviewed and responses can be considered. It is clear that there are new opportunities for optimising patient management pathways and in particular enhanced use of information technology. Changes in attitudes towards health and perceived risk are evident within both the catheter lab teams and our patient cohorts. Summating both the intellectual and emotional experiences of the pandemic are essential to prepare for either a second wave of COVID 19 or any new pandemic threat in the future.
End-stage heart failure patients should be treated instantly despite a pandemic with all-time available technology to ensure best outcomes
Authors: Bories Marie-Cécile , Abi Akar Ramzi
Published: December 2020

Since the earliest cases of coronavirus disease 2019 (COVID-19) infection were reported, our care delivery systems have been reorganized and challenged in unprecedent ways, specifically the cardiovascular community. COVID-19 poses a challenge for heart transplantation, affecting donor selection, immunosuppression, and posttransplant management. Left Ventricular Assist Device (LVAD) therapy is currently a viable option for patients with end-stage heart failure as a bridge to heart transplantation or destination therapy. Here, we present a therapeutic strategy for the management of acute HF with Intermacs profiles from 1 to 4, with or without Covid-19 infection, exemplified by serie of patients presenting with severe HF and successfully treated by LVAD therapy during the spread of the Covid-19 pandemic and the French national lockdown. This experience has shown that we still have the capacity to provide the right therapy for the right disease to the right patient. LVAD implantation seems to be the treatment of choice for advanced HF due to the lack of healthy donor hearts for cardiac transplantation. Covid or non-Covid context, we have to take care of our patients with end-stage HF the best we can.
Weighing Overall Fairness: A Critique of Balancing under the Criminal Limb of Article 6 of the European Convention on Human Rights
Authors: Samartzis Andreas
Published: December 2020

This article focuses on a specific standard by which the right to a fair trial is interpreted in the context of the right to legal assistance and the right to examine witnesses under Article 6 ECHR, the standard of overall fairness. The first section argues that the standard of overall fairness undermines the rule of law and represents a problematic conception of the right to a fair trial. The second section links overall fairness to the Court’s wider methodological approach to adjudication, namely ad hoc balancing, and establishes that ad hoc balancing is vulnerable to similar critiques. The third section advocates for a legal doctrine which rejects the theoretical assumptions of balancing and sets the basis for a reconceptualisation of the European Court of Human Rights’ approach to methodology and to the grant of remedies.
Spawning phenology of a rapidly shifting marine fish species throughout its range
Authors: Slesinger Emily , Jensen Olaf P , Saba Grace
Published: December 2020

Ocean warming is leading to poleward range shifts for many fish species, and while well described, potential life history phenology differences within fish populations along a gradient from their historic to current distributional range have not been studied. In a rapidly shifting fish population, the Northern stock of black sea bass (Centropristis striata), we investigated spawning phenology and output across the US Northeast Shelf to comprise locations in their historic and more recently occupied range near their northern range boundary. Spawning started later in the northern extreme of our study but also ended earlier, leading to decreased spawning duration from south to north. Spawning phenology was mostly driven by Julian day followed by temperature and latitude. Gonadosomatic index, a proxy for reproductive output, was lower in the northern region, indicating that black sea bass did not compensate for the shorter spawning season there. Hepatosomatic index was lower in the northern regions indicating lower pre-spawning liver energy reserves, potentially leading to lower reproductive output. These results suggest a potential for lower recruitment in the recently occupied range and should be further investigated to predict the impacts of ocean warming and for proactive fisheries management as black sea bass distributional range expands poleward.
The impact of gender on emotional reactions, perceived susceptibility and perceived knowledge about COVID-19 among the Israeli public
Authors: Levkovich Inbar , Shinan-Altman Shiri
Published: December 2020

Background

The current COVID-19 outbreak is seriously affecting the lives and health of people across the globe. While gender remains a key determinant of health, attempts to address the gendered dimensions of health face complex challenges.

Methods

In a cross-sectional study 482 participants (men=237, women=245) completed questionnaires on precautionary behaviour, perceived knowledge about COVID-19 risk factors, emotional reactions toward COVID-19 and perceived susceptibility. We examined gender differences in perceived knowledge about COVID-19 risk factors, healthy behaviours, threat perceptions and emotional responses, as well as the role of gender as a moderating factor.

Results

Women reported higher levels of precautionary behaviour (t(475)=3.91, p<0.001) and more negative emotional reactions toward COVID-19 (t(475)=6.07, p<0.001). No gender differences emerged in perceived susceptibility or knowledge about COVID-19. The multiple regression model is significant and explains 30% of the variance in precautionary behaviour, which was found to be higher among women and older participants, those with higher perceived knowledge about COVID-19 risk factors and those with higher emotional reactions. Gender exhibited a significant moderating role in the relationship between perceived knowledge and precautionary behaviour (B=0.16, SE=0.07, β=0.13, p=0.02, 95% CI 0.03 to 0.30).

Conclusion

Women exhibited higher levels of precautionary behaviour and emotional responses.
A Method for Diagnosing Organophosphate Pesticide Exposure in Humans Using Liquid Chromatography Coupled to Tandem Mass Spectrometry
Authors: Indapurkar Amruta S , Eangoor Padmanabhan , Yeh Jihee Stephanie , Vakkalanka Manideepika , Cashman John R , Knaack Jennifer S
Published: December 2020

Organophosphate (OP) pesticides are commonly utilized worldwide for agricultural purposes and pose a health threat through air, ground and water contamination. Here, we present a convenient method for diagnosing exposure to OP pesticides in humans. This immunoprecipitation method relies on extraction of butyrylcholinesterase (BChE), a biomarker of OP poisoning that adducts OP compounds, from human serum using agarose beads conjugated to anti-BChE antibodies. Extracted BChE was then digested with pepsin and analyzed for unadducted and OP-adducted peptides by high-performance liquid chromatography coupled to tandem mass spectrometry. To characterize and validate this method, pooled human plasma was exposed to parathion and dichlorvos to form diethoxyphospho, aged ethoxyphospho and dimethoxyphospho adducts with BChE. Untreated plasma was also analyzed for unadducted peptides. Additionally, samples were analyzed using Ellman’s assay to measure BChE functional activity. The percent inhibition of BChE was 53.5 ± 5.76 and 95.2 ± 0.37%, respectively, for plasma treated with parathion for 1 and 24 h. The percent inhibition was 97.2 ± 0.98% for plasma treated with dichlorvos for 1 h. The percent inhibition was 97.9 ± 0.41% when the plasma treated with parathion (for 1 and 24 h) and dichlorvos (for 1 h) were mixed. Individual adducts were quantified in a single chromatographic run. Untreated plasma contained 26.4 ± 1.87 ng/mL of unadducted BChE and no adducted peptides. In contrast, the plasma sample treated with both pesticides contained no unadducted BChE, but did contain 9.46 ± 1.10, 10.9 ± 0.98 and 14.1 ± 1.10 ng/mL of diethoxyphospho, aged ethoxyphospho and dimethoxyphospho peptides, respectively. The ability to identify and measure BChE and BChE adducts to parathion and dichlorvos is expected to be useful for diagnosing human exposure to multiple OP pesticides.
Parent Traumatic Events and Adolescent Internalizing Symptoms: The Mediating Role of Parental Depression Among Youth with Persistent Post-concussive Symptoms
Authors: Marcynyszyn Lyscha A , McCarty Carolyn A , Rivara Frederick P , Johnson Ashleigh M , Wang Jin , Zatzick Douglas F
Published: December 2020

Objective

Research has demonstrated associations between parental depression (PD) and negative psychological outcomes among their children. However, little is known about the pathways through which lifetime parent traumatic events (PTEs) influence their adolescents’ internalizing symptoms. Our study examined whether PD mediates the association between PTE and adolescent depressive and anxious symptoms among youth with persistent postconcussive symptoms (PPCS).

Methods

We used baseline data from a randomized effectiveness trial of collaborative care for treatment of persistent postconcussive symptoms among sports-injured adolescents aged 11–18 years. Parent–adolescent dyads were recruited from pediatric clinics throughout western Washington. Eligible adolescents had three or more PPCS that lasted for at least 1 month but <9 months and spoke English. Of 1,870 potentially eligible adolescents, 1,480 (79%) were excluded for not meeting the inclusion criteria. Of the eligible 390 adolescents, 189 (49%) declined to participate/consent. Participants included 200 parent–adolescent dyads (adolescent Mage = 14.7 years, SD = 1.7). Parent respondents were mostly female (83%) and mothers (81%). Adolescents reported on their depressive (Patient Health Questionnaire-9; PHQ-9) and anxious symptoms (Revised Child Anxiety and Depression Scale-Short Version [anxiety subscale]) and parents reported on their depressive symptoms (M = 3.7, SD = 3.7; PHQ-9).

Results

Mediation analyses revealed two (out of four) significant indirect effects of PTE on both adolescent and parent report of depressive symptoms, but not anxiety.

Conclusions

This study elucidates one pathway (PD) through which PTE history influences adolescent depressive symptoms, supporting a two-generation approach to pediatric patient care for youth experiencing PPCS.
Making Sense of the Gender Gap in South Koreans’ Attitudes towards North Korean Defectors
Authors: Lim Sijeong
Published: December 2020

South Korean women are less favourable towards open admission policies for North Korean defectors, less supportive of assistance to defectors, and less willing to integrate with defectors than are South Korean men. Such a gender gap contradicts the findings of studies on refugee attitudes in Western countries. This article proposes two distinct explanations for the gap: 1. intra-gender competition induced by a gendered labour market and gender-imbalanced defector inflows and 2. gendered outgroup attitudes where women show greater anxiety and aversion towards an unfamiliar outgroup than do men. The explanations are tested using annually repeated cross-sectional survey data (2007–18). I find more consistent support for the gendered outgroup attitude explanation. Whilst South Koreans of both genders increasingly see the two Koreas as socio-culturally distinct, such perceptions of otherness are more strongly linked to negative defector attitudes among South Korean women. I also provide first-cut evidence that knowledge of North Korean society and politics mitigates the outgroup anxiety and, in turn, can mitigate the gender gap in defector attitudes. These findings hold implications for defector and refugee policies in South Korea and other refugee host countries in the region.
Delayed presentation of a rare and complex multi-vessel pulmonary arteriovenous fistula following penetrating chest-wall trauma
Authors: Williams Aman B , Lax Lauren G
Published: December 2020

The formation of a pulmonary arteriovenous malformation (PAVM) following penetrating chest trauma is a rare occurrence, often rapidly fatal or requiring emergency surgery. Even rarer still, is for the malformation to formed by an entangled and grossly tortuous network of multiple arteries and veins, with symptoms and eventual presentation to a medical facility taking place years after the initial injury. Without substantial literature available, and nil regarding instances of more than one involved artery and vein, we present the case of a complex left-sided PAVM, becoming symptomatic 15 years after a chest-wall stabbing. Clinical examination revealed hypoxia, tachycardia and an extracardiac bruit—prompting delineation with a computed tomography pulmonary angiogram and revealing the PAVM. Subsequent attempt at endovascular embolization was unsuccessful, though interrogation provided vital planning information for workup of urgent open-surgical ligation and resection. Surgery carries high morbidity and mortality, as does natural progression if left undealt.
A programmable omnipotent Argonaute nuclease from mesophilic bacteria Kurthia massiliensis
Authors: Liu Yang , Li Wenqiang , Jiang Xiaoman , Wang Yaping , Zhang Zhiwei , Liu Qi , He Ruyi , Chen Quan , Yang Jun , Wang Longyu , Wang Fei , Ma Lixin
Published: December 2020

Argonaute (Ago) proteins are conserved nucleic acid-guided proteins present in all domains of life. Eukaryotic Argonaute proteins (eAgos) are key players in RNA interference pathways and function as RNA-guided RNA endonucleases at physiological temperatures. Although eAgos are considered to evolve from prokaryotic Argonaute proteins (pAgos), previously studied pAgos were unable to catalyze RNA-guided RNA cleavage at physiological temperatures. Here, we describe a distinctive pAgo from mesophilic bacteria Kurthia massiliensis (KmAgo). KmAgo utilizes DNA guides to cleave single-stranded DNA (ssDNA) and RNA targets with high activity. KmAgo also utilizes RNA guides to cleave ssDNA and RNA targets at moderate temperatures. We show that KmAgo can use 5′ phosphorylated DNA guides as small as 9-mers to cut ssDNA and RNA, like Clostridium butyricum Ago. Small DNA binding confers remarkable thermostability on KmAgo, and we can suppress the guide-independent plasmid processing activity of empty KmAgo by elevating the DNA guide loaded temperature. Moreover, KmAgo performs programmable cleavage of double-stranded DNA and highly structured RNA at 37°C. Therefore, KmAgo can be regarded as a DNA-guided programmable omnipotent nuclease for cleaving most types of nucleic acids efficiently. This study broadens our understanding of Ago proteins and could expand the pAgo-based DNA and RNA manipulation toolbox.
The forkhead transcription factor FOXK2 premarks lineage-specific genes in human embryonic stem cells for activation during differentiation
Authors: Ji Zongling , Li Yaoyong , Liu Sean X , Sharrocks Andrew D
Published: December 2020

Enhancers play important roles in controlling gene expression in a choreographed spatial and temporal manner during development. However, it is unclear how these regulatory regions are established during differentiation. Here we investigated the genome-wide binding profile of the forkhead transcription factor FOXK2 in human embryonic stem cells (ESCs) and downstream cell types. This transcription factor is bound to thousands of regulatory regions in human ESCs, and binding at many sites is maintained as cells differentiate to mesendodermal and neural precursor cell (NPC) types, alongside the emergence of new binding regions. FOXK2 binding is generally associated with active histone marks in any given cell type. Furthermore newly acquired, or retained FOXK2 binding regions show elevated levels of activating histone marks following differentiation to NPCs. In keeping with this association with activating marks, we demonstrate a role for FOXK transcription factors in gene activation during NPC differentiation. FOXK2 occupancy in ESCs is therefore an early mark for delineating the regulatory regions, which become activated in later lineages.