bluuebunny/crossref_metadata_2025 huggingface dataset:
Microstructure and mechanical properties of a nickel-base superalloy heavily alloyed with substitution elements
Authors: Zainullin R I , Ganeev A A , Shakhov R V , Mukhtarov S K , Imayev V M , Imayev R M
Published: January 2021

The present work is devoted to a study of the microstructure and mechanical properties of a new heat resistant nickel-base superalloy Ni-14(Al, Ta)-30.7(Co, Cr, W, Hf) (wt.%) intended for using as a die material. The superalloy contains about 70 vol.% of the γ′(NÎ3AI) phase and a small amount (about 3 vol.%) of carbides and topologically close-packed phases. Compression tests were carried for the new superalloy at 1000-1200°C. The superalloy showed the yield stress values at 1100-1200°C comparable with those obtained for the Russian VKNA-superalloys based on the γ′(NÍ3Al) phase. Tensile tests were performed for the cast and heat treated and wrought conditions of the superalloy. The tensile properties show that the new superalloy can be considered as an advanced disc material for gas turbine engines as well.
Effect of post-forging heat treatment on the microstructure and mechanical properties of a nickel-base superalloy SDZhS-15
Authors: Mukhtarova K S , Shakhov R V , Ganeev A A , Mukhtarov S K , Logunov A V , Imayev V M
Published: January 2021

The newly designed ingot-metallurgy Ni-base superalloy SDZhS-15 intended for disc applications was subjected to multiple heat treatment and forging in the temperature range (Ts-70)-Ts, where Ts is the γ’ solvus temperature, followed by solid solution treatment and ageing. A fine-grained microstructure was attained in the forged condition as a result of recrystallization processes occurring during processing. It was revealed that solution treatment at T>(Ts-50) led to a fast γ grain growth, which in turn led to a decrease in strength and ductility of the superalloy. At the same time, the solution treatment at slightly lower temperatures, at (Ts-60)-(Ts-50), allowed to save fine γ grains (d
γ
= 10-20 μm) and to provide the formation of secondary γ′ precipitates with a mean size of about 0.1 The superalloy in the forged and heat treated condition showed superior mechanical properties as compared with those of other disc superalloys.
Structure and properties of Cu-based alloys diluted by Pd and Ag
Authors: Volkova E G , Novikova O S , Kostina A E , Glukhov A V , Volkov A Yu
Published: January 2021

The microstructure, mechanical and electrical properties of Cu-Pd alloys (with Pd content not more than 8 at.%) and triple Cu-Pd-Ag alloys with 5 at.%Ag were studied. It was established that the strength and the recrystallization temperature of the Cu-Pd alloys increased with palladium content. A comparison of the electrical properties of these alloys when Pd content was increased from 0 to 8 at.%Pd was done. An anomaly was revealed in the Cu-5.9Pd and Cu-8Pd alloys: the plastic deformation does not lead to an increase in the electrical resistivity. It is due to the destruction of short range atomic order in the quenched Cu-Pd alloys under deformation. The alloying with silver leads to a further increase in strength with a constant electrical conductivity. It was found that annealing of the deformed Cu-Pd-Ag alloys at 200-300°C led to an increase in strength. It was shown that the effect was not related to the Pd-content and was due to silver only.
Effect of accumulative high-pressure torsion on the structure of steel 10
Authors: Ramazanov I A , Gunderov D V , Astanin V V , Sitdikov V D , Zakiryanova G T , Sharafutdinov A V
Published: January 2021

The effect of processing by accumulative high-pressure torsion on the structure of steel 10 is investigated. It is found that after processing by accumulative HPT, a stronger structure refinement takes place in steel 10 as compared to regular HPT processing for the same number of revolutions.
High density of shear bands in the Vitreloy bulk metallic glass subjected to high-pressure torsion
Authors: Astanin Vasily , Gunderov Dmitry , Qiang Ren Zhi , Valiev Ruslan , Wang Jing Tao
Published: January 2021

Plastic deformation by high-pressure torsion allows one to achieve high strains of bulk metallic glasses without their failure. It is shown that inclusions of the primary crystalline phase in the Vit105 alloy provoke the formation of cracks, and shear bands themselves have a complex composite structure and are prone to branching and merging during the development of deformation. The density of the bands reaches 1.76 μm−1, with a distance between them 80-120 μm.
Calculation of hardening contributions of the TiNi alloy undergoing martensitic transformations in a free state
Authors: Churakova A A , Gunderov D V , Tolstov N E , Magomedova D K
Published: January 2021

The paper reports on the studies of the effect of thermal cycling on the microstructure of the Ti - 50.8 at. % Ni alloy in coarse-grained and ultrafine-grained states, mechanical properties, and calculation of contributions to hardening in the studied states. The comparison of the calculated and experimental values of the yield stress in the TiNi alloy was carried out.
Influence of free torsion deformation modes on the microstructure and mechanical properties of commercially pure copper
Authors: Kodirov I S , Aleshin G N , Raab A G
Published: January 2021

The paper investigates the effect of the free torsion rate of cylindrical specimes of commercially pure copper (grade M1) on their deformed state, microstructure, and mechanical properties. The study of the microstructure was carried out by means of transmission electron microscopy and X-ray diffraction analysis in the central region and at the periphery of the deformed rod. The mechanical properties were evaluated by measuring the microhardness. It was found that an increase of the torsion rate, other things being equal, promotes more intensive strengthening and refinement of the microstructure.
Structure of copper-containing nanocomposites obtained by electrochemical synthesis
Authors: Isaeva I Yu , Ostaeva G Yu , Odinokova I V , Eliseeva E A , Busko V I
Published: January 2021

The properties of copper nanocomposites obtained by electrochemical reduction in an aqueous-alcohol electrolyte solution (CUSO4) with the addition of poly(N-vinylpyrrolidone) were investigated. Electrolysis was carried out at direct current using copper electrodes: the anode is made as a hollow cylinder, and the cathode in the form of a bundle of insulated wires with open cross sections, placed inside the cylinder with a working solution. The stabilizing properties of the polymer and the influence of the cathode on the electrochemical deposition processes were shown. The composition, morphology and size characteristics of synthesized copper-containing nanocomposites were determined. The resulting nanoparticles have a crystal cut, and also a high copper content.
Effect of the structural elements size of crumpled graphene on hydrogen sorption: atomistic simulation
Authors: Apkadirova N G , Krylova K A
Published: January 2021

The effect of the size of carbon flakes of crumpled graphene on the physical hydrogen sorption is considered using molecular dynamics simulation. Hydrogenated crumpled graphene was subjected to hydrostatic compression up to ε = 0.77, hydrogen dynamics in the dense structure is studied at 77 and 300 K. It has been found that the hydrogen sorption of crumpled graphene depends on its specific surface area. The highest sorption capacity was observed for crumpled graphene with carbon nanoflakes 20 nm in diameter. The difference in volumetric sorption capacity of flakes with the diameters of 9.5 and 20 nm was about 10% for a compression strain of ε = 0.77 at 20 ps at 77 K.
Molecular dynamics simulation of crumpled graphene filled with Ni nanoparticles
Authors: Safina L R , Murzaev R T , Krylova K A
Published: January 2021

Graphene-nickel composites are novel structures with improved properties intensively studied in the last decades. In the present work, molecular dynamics simulation is used to study the process of formation of a composite obtained from well-known crumplec graphene mixed with Ni nanoparticles on the atomistic level. To obtain the composite from initially separated structural units, hydrostatic compression at elevated temperatures is applied. As it is found, the composite structure can be obtained only at high temperatures ir 1200 < T < 1500 K range. Numerical tensile tests showed that the higher is the temperature during hydrostatic compression, the smaller is the pore size at the final stage of tension. Compression at high temperature leads to the formation of new chemical bonds between graphene flakes, supports the spread of Ni atoms inside the graphene structure and results in a formation of an excellent composite structure.
Contribution of structural parameters to the strength and electrical conductivity of Cu-0.5%Cr alloy subjected to ECAP and cold rolling
Authors: Sarkeeva E A , Alexandrov I V
Published: January 2021

The effect of cold rolling with a reduction rate of 95% at room temperature and subsequent aging on the evolution of the microstructure, strength properties and electrical conductivity of the Cu-0.5Cr alloy (wt.%), which is widely used in the electrical industry in the form of strips and ribbons, has been studied. The cold rolling and aging of the alloy was carried out in coarse-grained and ultrafine-grained states after equal-channel angular pressing. The regularities found were used to assess the contribution of various structural parameters to the level of strength properties as well as the electrical conductivity of the alloy in the obtained states.
Influence of rolling modes and the level of accumulated deformation on the mechanical and plastic properties of stainless austenitic steel AISI 304L
Authors: Raab A G , Raab G I , Dobatkin S V , Tokar A A , La P
Published: January 2021

The paper presents the results of studies of rolling modes (direct, reverse, cross ones) at 500°C for samples of stainless steel AISI 304L and their influence on mechanical and plastic properties of the material. The stress-strain state was investigated using a numerical simulation program and the deformation parameters of processing were established. The mechanical properties were studied by microhardness measuring and tensile testing methods. The results of the experiment were analyzed and discussed, and conclusions were drawn. The regularities of the effect of strength parameters depending on the modes of processing and accumulated deformation during rolling have been established.
Features of the formation of a diffusion layer and the mechanism of diffusion during boronizing of steels
Authors: Guryev A.M. , Ivanov S. G. , Guryev M. A. , Mei S. , Lygdenov B.D.
Published: January 2021

The paper presents the results of studies on the formation of a diffusion layer during the boriding of steel with a carbon content of 0.38 wt%. The study of diffusion coatings by SEM and TEM methods allows one to more clearly determine the mechanisms of diffusion of boron atoms and the formation of diffusion boride coatings. Diffusion of boron in the processes of diffusion boriding of iron-carbon alloys proceeds by a mixed mechanism: the delivery of active boron atoms to the diffusion front proceeds along the grain and phase boundaries. The reaction mechanism is realized by a gradual substitution of carbon with boron in iron carbides. Due to the continuous diffusion of boron, the reaction boundary is constantly moving in the direction from the surface to the core of the saturated material. In this case, as the diffusion proceeds, the concentration of carbon atoms under the boride layer constantly increases. This provides resistance to diffusion of boron atoms by the atomic mechanism and provokes diffusion by the reaction mechanism.
Microstructure and phase composition of Al-Nb metal-matrix composites produced by shear deformation under pressure
Authors: Danilenko V N , Kiekkuzhina L U , Nazarov K S , Mulyukov R R
Published: January 2021

Al and Nb billets with a coarse grain structure in the form of thin discs were stacked in the order of Al-Nb-Al and then deformed by shear under pressure. After the deformation the samples were annealed at 500°C for 30 min. The formation of an intermetallic compound AUNb was revealed by using X-ray diffraction and energy-dispersive spectroscopy. After postdeformation annealing, the amount of this compound increased. At the same time, the study of microhardness demonstrates a decrease of the value of microhardness after post-deformation annealing.
Dynamics of supersonic N-crowdions in bcc tungsten
Authors: Murzaev R T , Korznikova E A , Dmitriev S V
Published: January 2021

An interstitial atom placed in a close-packed atomic row of a crystal is called a crowdion. Such defects are highly mobile; they can move along the close-packed row at subsonic and even supersonic speeds, transferring mass and energy. In this paper, we consider the initial conditions for excitation of N-crowdions, in which N-atoms move simultaneously with high speed. The most efficient methods for initiating supersonic N-crowdions with N = 2 and 4 are demonstrated using molecular dynamics modelling for bcc tungsten.
Concentration wave method for description of all possible energy states of A2BC ordered alloy
Authors: Khalikov A R , Nguen V T , Valitov V A , Dmitriev S V
Published: January 2021

The procedure for describing all possible energy states of an alloy based on the concentration wave method proposed by Khachaturian is employed to describe all possible energy states of ordered A
2
BC alloy based on N-dimensional lattice. Within the framework of this method, a complete enumeration of the structures obtained by the superposition of N plane concentration waves with all possible wave vectors is carried out, provided that the given stoichiometry is preserved. For each such superposition, the order parameters on the first I coordination spheres are calculated, thereby determining the point in the I-dimensional order parameter space corresponding to the given structure. For the case of I = 2 it is shown that a complete enumeration of all structures generated by one plane concentration wave fills a non-convex figure in the space of two order parameters.
Properties of one-dimensional nonlinear vibrational modes in triangular lattice with Lennard-Jones interactions
Authors: Sunagatova I R , Subkhangulova A M , Semenova M N , Borisov D I , Semenov A S , Dmitriev S V
Published: January 2021

Crystal lattices support delocalized nonlinear vibrational modes (DNVMs), which are determined solely by the lattice point symmetry, and are exact solutions of the equations of atomic motion for any interatomic potential. DNVMs can be used for setting initial conditions to excite spatially localized vibrational modes called discrete breathers (DBs). In this study, DNVMs derived for instability can result in the formation of localized vibrational modes concentrating a significant part of the lattice energy. In some cases, localized vibrational modes can be obtained by imposing localizing functions upon DNVM.
Modelling of WEDM Parameters Using Taguchi & Fuzzy Logic
Authors: Sharma Siddharth , Goyal Ashish , Sharma Love Kishore
Published: January 2021

This work highlights the Fuzzy Logic approach for predicting best operating parameters of WEDM. This process is attracting the industries/researchers due to precision in machining. The only limitations that exist are high tool costing and lower value of finished surface. Four parameters are opted for conducting experiments viz Ton, Toff, Wire Feed & Current and their impacts are calculated for SRR and Ra. The DOE is done using Taguchi (L9) OA. ANOVA test for identification of parameters with high significance is considered.
Uncontaminating Concrete Mix Using Sugarcane Bagasse Ash: A Review on its Hardened Properties
Authors: Philip R B , Das G N , Kuriakose S K , Jacob D , Prabha A S
Published: January 2021

Concrete is one among the most used material for construction other than water. Cement is the important constituent of concrete. During the production of cement high amount of carbon dioxide is emitted and is responsible for global warming. High amount of cement production is causing environmental problem. Use of agro-waste materials like bagasse ash, increases the strength characteristics of concrete and also causes proper disposal of the waste materials. In this paper, use of sugarcane bagasse ash, an agro-waste product, as a partial replacement of the cement in concrete mix and its effect on the strength parameters of concrete are also identified on the basis of compressive strength, spilt tensile strength and flexural strength. This waste usage is very economical and also have positive impacts on minimizing environmental pollutions.
Parametric optimization of TIG welding of duplex stainless steel without filler rod by PCA method
Authors: Mondal S. , Nandi G. , Pal P. K.
Published: January 2021

The weld quality is mostly depended on the welding input factors. Welding quality is controlled by appropriately controlling the using process factors with sound knowledge base. The major influencing Tungsten Inert Gas (TIG) welding parameters are welding current, gas flow rate and speed of the welding. Controlling these parameters, the quality of the Duplex Stainless Steel (DSS) welding joints are improved. These welding process parameters are optimized to achieve the better quality of DSS welding joints. Here, the Principal Component Analysis (PCA) method and concept of Taguchi’s signal to noise ratio (S/N) are used to optimize the above TIG welding process parameters of UNS 2205 DSS. The quality of the TIG welding of DSS has been evaluated in term of tensile test. Statistical tool like Analysis of Variance (ANOVA) is applied to evaluate the significance of the individual factors on the desired responses like ultimate tensile strength, yield strength etc. The optimal result is verified by the additional experiment. This result shows the application possibility of the PCA method for incessant development of welding quality of DSS in many fields, like chemical industries, oil & gas refineries, manufacturing industries etc.
Analysis of a Structure for Efficient Energy Utilization Using Design Builder
Authors: Bharath B , Sami Abdus , Rastogi Kartikeya
Published: January 2021

A major concern for the Indian Construction industry is its negligence of energy efficiency aspects of the various building projects being undertaken nowadays. Moreover, it is a concern for the citizens as well. Heat island and climate change phenomenon has led to a massive increment in the ambient temperatures, intensified reliance on energy resources, created discomfort conditions. By 2030, India’s dependence on energy imports is expected to exceed 53% of the country’s total energy consumption [5]. As growth is inevitable, a multifaceted and scalable solution is needed to temper the environmental impacts of growing cities. The growth in the cities leads to hot urban environments. The temperature variation between urban areas and adjacent rural areas is called the “heat island phenomenon”. It is found that the heat island phenomenon triples the peak electricity demand, doubles the building’s cooling load, and reduces the mechanical cooling system’s coefficient of performance by 25% [5]. To ease our lives in such a climate we need to invent the cooling techniques and those too are energy and cost-efficient. Many of the environmentalists and architects are putting forward their contributions toward it, suggesting solutions to make use of more and more sustainable systems of energy not like those being practiced in earlier times like courtyards and cavities but newer techniques which merges out with the present form of architecture, few of which are namely, the green roof techniques, terracotta pot, outdoor cooling systems. In this paper, we have analysed the Academic Block 4 building of our college and estimated the size of an outdoor cooling plant based on weather data, occupancy, and constructional details of the building such as heat absorbed by various facades due to internal and solar gains, etc.
Combustion analysis of porous radiant burner for commercial cooking applications
Authors: Sharma Loveneesh , Sehgal Satbir Singh , Tonk Ravinder , Chhabra Saurabh
Published: January 2021

High efficiency and low efficiency were observed by using porous burner technology for commercial cooking. The whole research consists of survey of these three types of burners. Like burners diameter having convergent 100mm, straight 100mm and80mm divergent shape burner. LPG is the fuel i.e. liquid petroleum gas is used in the all experiment. The two zones combustion and preheating zones comprise by a porous burner. Preheating zone having steel balls of width 6.5mm where combustion zone has Sic matric of 10ppi was used. 150mm is the constant altitude of three burners comprise of combustion zone and having equivalence ratio from 0.10-0.60. The range at which burner was operated 79% is the maximum efficiency analyzed for porous burner having dimensions like 100mm diameter at power equal to 0.84 kW and equivalence ratio (Φ) equal to 0.49.
Identification of Fruits Using Deep Learning Approach
Authors: Bongulwar Deepali M
Published: January 2021

The paper intends to build a Model for the identification and classification of fruits using the concept of deep learning. The objective is to build an automatic system for feature extraction using convolutional neural networks. The system can sort the fruits. It can be put-to-use in checking the condition of fruits, whether they are fresh or not. The self-service system in the retail market can use it to identify fruits. The proposed system uses high quality ‘ImageNet’ dataset. The dataset consists of five different categories of fruit images. Dataset is very challenging. The model uses Convolutional Neural Networks to identify fruits from images. The accuracy obtained is 92.23%. Deep learning outperforms machine learning algorithms.
Serrated flow behaviors in a Ni-based superalloy
Authors: Zhang Xiaoyang , Dong Ruifeng , Zhao Yuhong , Liu Dong , Yang Ling , Hou Hua
Published: January 2021

Serrated flow behaviors in Ni-20Cr-18W alloy were studied under different deformation conditions. It was found that there are no serrations observed on the tensile curves of the alloy at the temperature of lower than 250 °C and the strain rate of 10−3 s−1. As the deformation temperature improves, the serrations first starts with the type A (250 °C) and transfers to the mixed type A + B (300 °C and 400 °C), then to the mixed type B + C (500 °C). Meanwhile, the serration behaviors are closely related with the strain rate. It showed that when the deformation temperature is fixed, the serration curves starts with the type A (10−3 s−1), then transfers to the mixed type A + B (10−2 s−1) and eventually to type D (10−1 s−1) with the increasing strain rates from 10−3 s−1 to 10−1 s−1. Results showed that the serration behaviors of the alloy are related to the normal PLC effect. Combined with the McCormick’s model, the activation energy for the serrated flow behavior in this alloy is calculated to be 103.386 kJ mol−1 and the value of m + β to be 2.514, which suggests that the serrated flow of Ni-20Cr-18W superalloy is related to the interplay between the substitutional solute atoms and the movable dislocations.
The role of twist on tensile and frictional characteristics of aramid filament yarns (AFYs)
Authors: Ding Zuowei , Zhao Huihui , Hu Wanjin , Wang Rui
Published: January 2021

In this study, the role of twist on the tensile and frictional characteristics of aramid filament yarns (AFYs) were systematically studied. The results revealed that the twist is incredibly crucial in optimizing the final properties of AFYs. It was found that the extension at break and the initial modulus had a high rise with the increase of the twist angle. Furthermore, an optimum twist value provided the maximum breaking strength of AFYs. Meanwhile, breaking strength emerged the tendency of enhancement firstly and then descended continuously till to the fracture of AFYs. In addition, it was inferred that the larger the twist angle, the more sharply the aramid filaments were drafted. In conclusion, if reasonably controlled, AFYs will emerge better tensile capability in axial direction, which are significant in actual industry use, especially in the field that sustained destructive power and constant friction.
Coherent IC-sheaves on type 𝐴_{𝑛} affine Grassmannians and dual canonical basis of affine type 𝐴₁
Authors: Finkelberg Michael , Fujita Ryo
Published: January 2021

The convolution ring
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper K Superscript upper G upper L Super Subscript n Superscript left-parenthesis script upper O right-parenthesis right-normal-factor-semidirect-product double-struck upper C Super Superscript times Baseline left-parenthesis normal upper G normal r Subscript upper G upper L Sub Subscript n Subscript Baseline right-parenthesis">

K

G

L
n

(

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G
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K^{GL_n(\mathcal {O})\rtimes \mathbb {C}^\times }(\mathrm {Gr}_{GL_n})

was identified with a quantum unipotent cell of the loop group

L
S

L
2

LSL_2

in Cautis and Williams [J. Amer. Math. Soc. 32 (2019), pp. 709–778]. We identify the basis formed by the classes of irreducible equivariant perverse coherent sheaves with the dual canonical basis of the quantum unipotent cell.
Training matters! Narrative from a Black scientist
Authors: Riggs Blake
Published: January 2021

As STEM (Science, Technology, Engineering, and Math) professionals, we are tasked with increasing our understanding of the universe and generating discoveries that advance our society. An essential aspect is the training of the next generation of scientists, including concerted efforts to increase diversity within the scientific field. Despite these efforts, there remains disproportional underrepresentation of Black scientists in STEM. Further, efforts to recruit and hire Black faculty and researchers have been largely unsuccessful, in part due to a lack of minority candidates. Several factors contribute to this including access to opportunities, negative training experiences, lack of effective mentoring, and other more lucrative career options. This is a narrative of a Black male scientist to illustrate some of the issues in retaining Black students in STEM and to highlight the impact of toxic training environments that exists at many institutions. To increase Black participation in STEM careers, we must first acknowledge, then address, the problems that exist within our STEM training environments in hopes to inspire and retain Black students at every level of training.
2. Reconstructing ancient Egypt
Authors: Shaw Ian
Published: January 2021

‘Reconstructing ancient Egypt’ discusses the challenge of reconstructing ancient Egypt. New paradigms have been adopted by different generations of Egyptologists, gradually transforming the accepted picture of ancient Egyptian culture. Moreover, new methods, such as innovative excavation techniques or sophisticated processes of scientific analysis, have, at various times, altered people's perceptions of the surviving evidence from ancient Egypt. An important question to ask is: what can geology and archaeology reveal about the origins of the Narmer Palette? The discoveries of the Avaris frescos and the Amarna Letters, as well as the excavations of Flinders Petrie, are all important parts of this history.
7. Death
Authors: Shaw Ian
Published: January 2021

‘Death’ describes ancient Egyptian attitudes to death and the cult of Osiris, looking at the tomb of King Djer at Abydos. The tomb has been regarded as the ultimate, quintessential royal funerary memorial: the mythical burial place of the god Osiris, whose entire religious cult was intimately connected with the concept of the dead king. The combination of Osiris's associations with fertility and death almost inevitably ensured that he became the ultimate god of resurrection. Thus, it became essential for the mummified body to be associated with Osiris in order to gain eternal life. Of course Egyptian mummification and Egyptian funerary beliefs are important areas of study within the broader subject of ‘death’.
8. Religion
Authors: Shaw Ian
Published: January 2021

‘Religion’ studies ancient Egyptian religion, the history of which was at one stage concerned principally with the beliefs and temples of the pharaonic period. Now it has become increasingly clear that there is a significant prehistory of Egyptian religion. If the provision of offerings represents a relatively familiar aspect of Egyptian religion, there is another recurrent aspect of many of the Egyptian religious cults that Egyptologists of the late 19th and early 20th century frequently preferred to ignore. This was the tendency towards ‘phallocentrism’, involving cults dedicated to very obviously ithyphallic gods. The relationship of Egyptian religion with Egyptian kingship and Egyptian ideology is an important area to examine.
9. Egyptomania
Authors: Shaw Ian
Published: January 2021

‘Egyptomania’ highlights the phenomenon of Egyptomania. In this recycling and exploitation of the ancient Egyptian database, some aspects of the culture and history have tended to appeal more to different ages or audiences. One of the most obvious topics of fierce interpretative debate over the years has been the question of why the pyramids took the form that they did, and what this suggests about the purpose that they served. This ‘pyramidology’ is virtually a subject in its own right. It is important to reflect on the sculpting and deconstruction of the images of Akhenaten, Nefertiti, and Cleopatra and consider the rise of the ‘alternative’ Egyptologist.
What’s ‘neo’ about liberalism?
Authors: Steger Manfred B. , Roy Ravi K.
Published: January 2021

This chapter discusses the core ideas and principles of neoliberalism. The best way to conceptualize neoliberalism is to think of it as four intertwined manifestations: an ideology; a mode of governance; a policy package; and a particular form of capitalism. Built upon the classical liberal ideal of the self-regulating market, neoliberalism comes in several strands and variations. Although neoliberalism comes in several forms, one can find an early systematic formulation of its economic principles in those of the Mont Pelerin Society. Founded in 1947 by Friedrich August von Hayek, the Society sought to revive classical liberalism in its attempt to challenge the dominance of Keynesian ideas.
Neoliberalism in the Asia-Pacific region
Authors: Steger Manfred B. , Roy Ravi K.
Published: January 2021

This chapter traces the evolution of neoliberalism in the Asia-Pacific Region, looking at the economic developments of Japan, China, and India. It should be noted that in Asian countries, the market-oriented ideas of liberalization, deregulation, and privatization had to contend with an opposing dynamic of state interventionism and economic centralism. Ultimately, neoliberalism in the Asia-Pacific Region evolved within highly differentiated political-economic systems that were rooted in a regional developmental state model. Different nations have found unique ways of entering an increasingly globalized marketplace. Once these Asian governments adapted neoliberalism to meet their specific needs, they scarcely hesitated to incorporate suitable portions of an economic nationalist programme.
Seven threats to thinking about ethics
Authors: Blackburn Simon
Published: January 2021

‘Seven threats to thinking about ethics’ discusses the seven threats to ethical thinking, looking at ideas that destabilize one when one thinks about standards of choice and conduct. In various ways, these ideas seem to suggest that ethical thought is somehow impossible. They are important because they themselves can seep into the moral environment. When they do, they can change what people expect from each other and themselves, usually for the worse. How big are the threats of the death of God, relativism, egoism, evolutionary theory, determinism and futility, unreasonable demands, and the false consciousness?
Some ethical ideas
Authors: Blackburn Simon
Published: January 2021

‘Some ethical ideas’ explores some ethical ideas on desire, happiness, freedom, birth, and death. The flexibility of the term ‘freedom’ undoubtedly plays a huge role in the rhetoric of political demands, particularly when the language of rights mingles with the language of freedom. The enemy here would be any elitism, or paternalism, supposing that some particular kinds of people—through superior reason or knowledge or wisdom—are best fitted to govern the rest, since they know people’s interests better than the people themselves do. The language of ‘natural rights’ is an important consideration within ethical ideas and this includes the concepts of decency, civility, and trust.
Introduction
Authors: Wilson Charles Reagan
Published: January 2021

The ‘Introduction’ provides an overview of the American South. Its early history illuminates the expansion of Europe into the New World, creating a colonial, plantation, slave society that made it different from other parts of the United States. Two broad geographical subdivisions anchor what became known as “the South”: an Uplands and a Lowlands. Ultimately, speaking of the South brings attention to the importance of regionalism in American history. Atlanta Olympics refurbished the South’s claim to a special southern hospitality, epitomizing such themes as race relations, economic development, and cultural expression that figure prominently in the larger story of the American South.
7. Hybrid sounds
Authors: Wilson Charles Reagan
Published: January 2021

‘Hybrid sounds’ highlights southern music. The first association of music with the American South came from the presence of African American slaves. The pre-Civil War blackface minstrel shows displayed southern connections in its imagery of the plantation. After emancipation, African Americans gained employment in such groups as the Georgia Minstrels, as they moved to New Orleans, Memphis, and St. Louis, where they adopted the trumpet, the piano, and other instruments that soon became familiar in the music of black southerners. Sacred music, blues music, jazz, and folk music were all important musical genres which shaped Southern culture and the importance of the commercialization of African American music played a role.
Rhynchophylline improves trophocyte mobility potential by upregulating ZEB1 level via the inhibition of miR-141-3p level
Authors: Yang Qian , Zheng Meiyun , Yan Jinyu , Wu Jun , Liu Xiang
Published: January 2021

Preeclampsia (PE) is characterized by the impaired invasive ability of trophocytes, which can be modulated by microRNAs (miRs). In the current study, the effects of rhynchophylline (Rhy) on the viability and invasive ability of trophocytes were explored by focusing on miR-141-3p/ZEB1 axis. The level of miR-141-3p was modulated in human trophocytes and the changes in cell viability, apoptosis, invasive ability, and ZEB1 level were detected. Then the trophocytes with miR-141-3p overexpression were treated with Rhy and the effects on trophocyte phenotypes were assessed. The induced miR-141-3p level suppressed cell viability, induced apoptosis, and inhibited invasion and ZEB1 level in trophocytes. The treatment of Rhy restored the viability and invasive ability of trophocytes under the overexpression of miR-141-3p, indicating the protective effects of Rhy on trophocytes. The findings in the current study highlighted the protective effects of Rhy on trophocytes during PE progression, which was associated with the inhibition of miR-141-3p.
Perspectives of using Cloud computing in integrative analysis of multi-omics data
Authors: Augustyn Dariusz R , Wyciślik Łukasz , Mrozek Dariusz
Published: January 2021

Integrative analysis of multi-omics data is usually computationally demanding. It frequently requires building complex, multi-step analysis pipelines, applying dedicated techniques for data processing and combining several data sources. These efforts lead to a better understanding of life processes, current health state or the effects of therapeutic activities. However, many omics data analysis solutions focus only on a selected problem, disease, types of data or organisms. Moreover, they are implemented for general-purpose scientific computational platforms that most often do not easily scale the calculations natively. These features are not conducive to advances in understanding genotype–phenotypic relationships. Fortunately, with new technological paradigms, including Cloud computing, virtualization and containerization, these functionalities could be orchestrated for easy scaling and building independent analysis pipelines for omics data. Therefore, solutions can be re-used for purposes that they were not primarily designed.

This paper shows perspectives of using Cloud computing advances and containerization approach for such a purpose. We first review how the Cloud computing model is utilized in multi-omics data analysis and show weak points of the adopted solutions. Then, we introduce containerization concepts, which allow both scaling and linking of functional services designed for various purposes. Finally, on the Bioconductor software package example, we disclose a verified concept model of a universal solution that exhibits the potentials for performing integrative analysis of multiple omics data sources.
Curation of over 10 000 transcriptomic studies to enable data reuse
Authors: Lim Nathaniel , Tesar Stepan , Belmadani Manuel , Poirier-Morency Guillaume , Mancarci Burak Ogan , Sicherman Jordan , Jacobson Matthew , Leong Justin , Tan Patrick , Pavlidis Paul
Published: January 2021

Vast amounts of transcriptomic data reside in public repositories, but effective reuse remains challenging. Issues include unstructured dataset metadata, inconsistent data processing and quality control, and inconsistent probe–gene mappings across microarray technologies. Thus, extensive curation and data reprocessing are necessary prior to any reuse. The Gemma bioinformatics system was created to help address these issues. Gemma consists of a database of curated transcriptomic datasets, analytical software, a web interface and web services. Here we present an update on Gemma’s holdings, data processing and analysis pipelines, our curation guidelines, and software features. As of June 2020, Gemma contains 10 811 manually curated datasets (primarily human, mouse and rat), over 395 000 samples and hundreds of curated transcriptomic platforms (both microarray and RNA sequencing). Dataset topics were represented with 10 215 distinct terms from 12 ontologies, for a total of 54 316 topic annotations (mean topics/dataset = 5.2). While Gemma has broad coverage of conditions and tissues, it captures a large majority of available brain-related datasets, accounting for 34% of its holdings. Users can access the curated data and differential expression analyses through the Gemma website, RESTful service and an R package.

Database URL: https://gemma.msl.ubc.ca/home.html
Is It Possible to Obtain the Chemical Profile From Ethanol-Preserved Specimens? The Hydrocarbon and Fatty Acid Composition of the Social WaspPolybia paulista(Hymenoptera: Vespidae: Epiponini)
Authors: da Silva Cunha Dayana Alves , Telles Menezes Rodolpho Santos , Lima Cardoso Claudia Andrea , Antonialli Junior William Fernando
Published: January 2021

Cuticular hydrocarbons perform multiple functions in insects such as protecting against desiccation and pathogenic infection, and signaling interactions. Evaluation of cuticular hydrocarbon (CHC) profiles of insects is commonly performed by extraction using a nonpolar solvent such as hexane. Specimens intended for CHC analysis are ideally handled by avoiding contact with solvents such as ethanol. However, insects are frequently stored in ethanol after collection, especially if intended for molecular analysis. To determine if it is possible that chemical compounds in the cuticles of specimens can withstand previous exposure to ethanol, we evaluated the efficiency of CHC extraction from specimens preserved in 95% ethanol. We extracted cuticular compounds from specimens of the social wasp Polybia paulista (Ihering) with no contact with ethanol solvents and compared them with those from specimens stored in 95% ethanol. We analyzed chemical composition from wasps and the 95% ethanol in which they had been stored by a gas chromatograph coupled to a mass spectrometer. In total, 56 compounds were detected: 50 that were classified as hydrocarbons which were mostly branched alkanes, followed by linear alkanes and alkenes. Three compounds were identified as fatty acids, and three compounds were unidentifiable. The ethanol-preserved specimens showed similar chemical profiles to those of specimens that had no contact with ethanol. Thus, we suggest that it is possible to study the chemical profiles of ethanol-preserved specimens.
Predictors of survival in paediatric mitral valve replacement
Authors: Brancaccio Gianluca , Trezzi Matteo , Chinali Marcello , Vignaroli Walter , D’Anna Carolina , Iodice Francesca , Giorni Chiara , Iacobelli Roberta , Iorio Fiore , Galletti Lorenzo , Croci Ileana , Carotti Adriano
Published: January 2021

OBJECTIVES

The aim of this study was to identify the predictors of death and of reintervention after mitral valve replacement (MVR) in children.

METHODS

A single-centre retrospective study was performed including 115 patients under the age of 18 undergoing MVR between 1982 and 2019. For all patients, the ratio of prosthetic valve size (diameter in mm) to weight (kg) at surgery was calculated and long-term result was assessed. The primary outcome was freedom from mitral valve (MV) re-replacement. The composite secondary outcome was freedom from death or transplant.

RESULTS

Fifty-four patients had a previous surgical attempt to MV repair. The median age at surgery was 5.5 years (interquartile range 1.21–9.87). Death/transplant-free survival was 77 ± 4% at 5 years and 72 ± 5% at 10 years. Univariate analysis showed a size/weight ratio higher than 2 and age <2 years as significant risk factors for death or transplant. Freedom from MV re-replacement at 5 and 10 years was 90 ± 3% and 72 ± 6%, respectively. Biological prosthesis implanted at first replacement (P = 0.007) and size/weight ratio higher than 2 (P = 0.048) were predictors of reoperation. Significant upsizing (P < 0.0001) of mitral prosthesis was observed at re-replacement.

CONCLUSIONS

MVR is a viable strategy in children with unrepairable MV disease. Mortality can be predicted based on size/weight ratio and age <2 years. MV re-replacement can be performed with low morbidity and mortality and a larger-size prosthesis can often be placed at the time of redo.
Adult coronary artery bypass grafting by congenital surgeons—a propensity matched analysis
Authors: Rapetto Filippo , Bruno Vito D , Rajakaruna Cha , Bryan Alan J , Parry Andrew J , Caputo Massimo , Stoica Serban C
Published: January 2021

OBJECTIVES

Surgical myocardial revascularization will be increasingly needed in adult patients with congenital heart disease. We investigated the results of coronary artery bypass grafting (CABG) performed on adults by congenital cardiac surgeons at our institution.

METHODS

We conducted a retrospective, single-centre study. Adults undergoing isolated or combined CABG from 2004 to 2017 were included. Early and late outcomes were analyzed for the whole cohort. Furthermore, a propensity matched analysis was conducted comparing the results of isolated CABG between congenital and adult surgeons.

RESULTS

A total of 514 and 113 patients had isolated and combined CABG for acquired heart disease, respectively. A total of 33 patients had myocardial revascularization at the time of surgery for congenital heart disease. Overall early mortality was 1.2%, the rate of re-exploration for bleeding was 4.5%, and an internal mammary artery to left anterior descending artery graft was used in 85.6% patients. One-year survival was 97.5% (96.2–98.8%), and 5-year survival was 88.0% (84.8–91.3%). After propensity matching (468 pairs), early mortality (0.6% vs 1.2%, P = 0.51), re-exploration for bleeding (3.6% vs 3.0%, P = 0.72), use of internal mammary artery to left anterior descending artery graft (92.7% vs 91.9%, P = 0.70) and late survival did not differ between congenital surgeons and adult surgeons, respectively.

CONCLUSIONS

Surgical myocardial revascularization can be required for adult congenital patients in a broad spectrum of clinical situations. Despite lower volumes, congenital cardiac surgeons perform CABG safely and with results that are comparable to those of the adult surgeons at our centre.
Utility of the CHA2DS2-VASc score for predicting ischaemic stroke in patients with or without atrial fibrillation: a systematic review and meta-analysis
Authors: Siddiqi Tariq Jamal , Usman Muhammad Shariq , Shahid Izza , Ahmed Jawad , Khan Safi U , Ya’qoub Lina , Rihal Charanjit S , Alkhouli Mohamad
Published: January 2021

Aims

Anticoagulants are the mainstay treatment for stroke prevention in patients with non-valvular atrial fibrillation (NVAF), and the CHA2DS2-VASc score is widely used to guide anticoagulation therapy in this cohort. However, utility of CHA2DS2-VASc in NVAF patients is debated, primarily because it is a vascular scoring system, which does not incorporate atrial fibrillation related parameters. Therefore, we conducted a meta-analysis to estimate the discrimination ability of CHA2DS2-VASc in predicting ischaemic stroke overall, and in subgroups of patients with or without NVAF.

Methods and results

PubMed and Embase databases were searched till June 2020 for published articles that assessed the discrimination ability of CHA2DS2-VASc, as measured by C-statistics, during mid-term (2–5 years) and long-term (>5 years) follow-up. Summary estimates were reported as random effects C-statistics with 95% confidence intervals (CIs). Seventeen articles were included in the analysis. Nine studies (n = 453 747 patients) reported the discrimination ability of CHA2DS2-VASc in NVAF patients, and 10 studies (n = 138 262 patients) in patients without NVAF. During mid-term follow-up, CHA2DS2-VASc predicted stroke with modest discrimination in the overall cohort [0.67 (0.65–0.69)], with similar discrimination ability in patients with NVAF [0.65 (0.63–0.68)] and in those without NVAF [0.69 (0.68–0.71)] (P-interaction = 0.08). Similarly, at long-term follow-up, CHA2DS2-VASc had modest discrimination [0.66 (0.63–0.69)], which was consistent among patients with NVAF [0.63 (0.54–0.71)] and those without NVAF [0.67 (0.64–0.70)] (P-interaction = 0.39).

Conclusion

This meta-analysis suggests that the discrimination power of the CHA2DS2-VASc score in predicting ischaemic stroke is modest, and is similar in the presence or absence of NVAF. More accurate stroke prediction models are thus needed for the NVAF population.
Withdrawn as duplicate: Optimized Implementation of cardiac resynchronization therapy – a call for action for referral and optimization of care
Authors: Mullens Wilfried , Auricchio Angelo , Martens Pieter , Witte Klaus , Cowie Martin R , Delgado Victoria , Dickstein Kenneth , Linde Cecilia , Vernooy Kevin , Leyva Francisco , Bauersachs Johann , Israel Carsten W , Lund Lars , Donal Erwan , Boriani Giuseppe , Jaarsma Tiny , Berruezo Antonio , Traykov Vassil , Yousef Zaheer , Kalarus Zbigniew , Cosedis Nielsen Jens , Steffel Jan , Vardas Panos , Coats Andrew , Seferovic Petar , Edvardsen Thor , Heidbuchel Hein , Ruschitzka Frank , Leclercq Christophe
Published: January 2021

This article has been withdrawn due to a publisher error that caused the article to be duplicated. The definitive version of this article is published under https://doi.org/10.1093/europace/euaa411.