bluuebunny/crossref_metadata_2025 huggingface dataset:
Large variations in global irrigation withdrawals caused by uncertain irrigation efficiencies
Authors: Puy Arnald , Lankford Bruce , Meier Jonas , van der Kooij Saskia , Saltelli Andrea
Published: February 2022

An assessment of the human impact on the global water cycle requires estimating the volume of water withdrawn for irrigated agriculture. A key parameter in this calculation is the irrigation efficiency, which corrects for the fraction of water lost between irrigation withdrawals and the crop due to management, distribution or conveyance losses. Here we show that the irrigation efficiency used in global irrigation models is flawed for it overlooks key ambiguities in partial efficiencies, irrigation technologies, the definition of ‘large-scale’ irrigated areas or managerial factors. Once accounted for, these uncertainties can make irrigation withdrawal estimates fluctuate by more than one order of magnitude at the country level. Such variability is larger and leads to more extreme values than that caused by the uncertainties related with climate change. Our results highlight the need to embrace deep uncertainties in irrigation efficiency to prevent the design of shortsighted policies at the river basin-water-agricultural interface.
China’s power transformation may drastically change employment patterns in the power sector and its upstream supply chains
Authors: Zhou Sili , Chen Bin , Wei Wendong , Liu Zhaohui , Song Song , Feng Kuishuang , Li Jiashuo
Published: February 2022

China’s power sector, as the major CO2 emitter, has experienced significant restructuring that has had profound impacts on employment in both power and its upstream sectors. Combining input–output and structural path analysis, we quantified the direct and indirect impacts of power transformation on employment in China between 2012 and 2017. Direct employment in the power generation sector witnessed a net growth of 0.12 million, while over 10 times that number of jobs (1.40 million) have been lost in the upstream sectors, mainly in coal mining and washing, finance, oil and gas extraction and transportation. Among the top 10 critical paths, the share of employment driven by solar and wind power increased to 12.31% in 2017, more than nine times that in 2012. Furthermore, three scenarios have been set up to evaluate the employment patterns in 2030 and 2050. Under the 1.5 °C scenario, projection shows that the power sector could support over 5 million jobs in 2050, with more than 80% of these being related to renewable energy. Policy suggestions for a just transition, such as resettlement of laid-off workers and job transfer in upstream industries, are comprehensively discussed.
Statistics of the maximum and the convex hull of a Brownian motion in confined geometries
Authors: De Bruyne Benjamin , Bénichou Olivier , Majumdar Satya N , Schehr Grégory
Published: February 2022

We consider a Brownian particle with diffusion coefficient D in a d-dimensional ball of radius R with reflecting boundaries. We study the maximum M

x
(t) of the trajectory of the particle along the x-direction at time t. In the long time limit, the maximum converges to the radius of the ball M

x
(t) → R for t → ∞. We investigate how this limit is approached and obtain an exact analytical expression for the distribution of the fluctuations Δ(t) = [R − M

x
(t)]/R in the limit of large t in all dimensions. We find that the distribution of Δ(t) exhibits a rich variety of behaviors depending on the dimension d. These results are obtained by establishing a connection between this problem and the narrow escape time problem. We apply our results in d = 2 to study the convex hull of the trajectory of the particle in a disk of radius R with reflecting boundaries. We find that the mean perimeter ⟨L(t)⟩ of the convex hull exhibits a slow convergence towards the perimeter of the circle 2πR with a stretched exponential decay

2
π
R
−

⟨

L

(

t

)

⟩

∝

R

(

D
t

)

1
/
4

e

−
2

2
D
t

/
R

. Finally, we generalise our results to other confining geometries, such as the ellipse with reflecting boundaries. Our results are corroborated by thorough numerical simulations.
Justification of the Technology of Construction of Mine Shafts for the Conditions of the Maly Kuibas Deposit
Authors: Kalmykov V N , Zubkov A A , Volkov P V , Kulsaitov R V
Published: February 2022

The technology of construction of mine shafts for the conditions of the Maly Kuibas deposit is presented. The dimensions of the cross-section of the mine shafts are selected. The parameters of drilling and blasting operations have been calculated. Selected equipment for drilling holes in the borehole and loading the blasted rock mass. The lifting parameters were determined, the ropes were selected, and the lifting machines were selected. The technological schemes and methods of construction of shafts are considered. Designs of mine headframes are proposed.
Assessment of the Possibility of Using ROV in the Mode of Joint Traffic with the Support Vessel
Authors: Kostenko V V , Mokeeva I G
Published: February 2022

The correspondence of the characteristics of the propulsion and steering complex (PSC) to the values required to compensate for the response of the communication cable determines the efficiency of using tethered underwater vehicles. The report assesses the requirements for the thrust characteristics of the PSC, which ensures the maneuvering of the vehicle relative to the carrier or garage in the mode of movement of the complex along an extended bottom object. The assessment is based on the results of calculating the tension of the communication cable in the stream, due to the joint movement of the tethered system “carrier-garage-vehicle”. This tension, together with the hydrodynamic resistance of the apparatus body, determine the requirements for the thrust characteristics of the PSC, as well as for the power supply system of the complex as a whole. An algorithm is proposed for calculating the tension of the communication cable between the vehicle and carrier in a stationary flow, based on the equation of a chain line and numerical integration of the equations of an inextensible flexible thread. An example of using the proposed methodology for calculating the variants of a tethered system is given.
Assessment of the Production Potential of the Arctic Mining Sector
Authors: Tsukerman V A , Goryachevskaya E S
Published: February 2022

It is defined that the development of the world economic system in modern conditions is largely determined by the consumption of natural and, first of all, mineral resources. The process of exploiting Arctic mineral resources is complicated by specific features associated with taking into account climatic features, increased costs and conditions of economic activity. It is shown that in recent years experts showed increased interest in assessing industrial potential which is determined by the need to increase the pace of territorial innovation and industrial development. In this regard the aim of the work is to assess the production potential of the mining sector of the Arctic economy which determines the possibilities of using the entire set of resources for effective growth. The performed analysis of the production potential of the Arctic mining sector showed significant differences in the functioning of industrial enterprises in the Arctic regions. It is determined that the Arctic regions are characterized by raw materials specialization. The extraction and processing of minerals in the Arctic regions accounts for more than 50% of the added value and about 60% of tax revenues to the budgetary system of the Russian Federation.

It is concluded that the most significant production potential of the Arctic mining sector is typical for the Nenets Autonomous Okrug and the minimum - for the Murmansk Region and the Chukotka Autonomous Okrug. It is shown that in terms of production potential the Arctic regions are ahead of the average Russian values but at the same time they are characterized by a low level of innovation activity.

To increase the production potential of the Arctic mining sector it is necessary to conduct scientific research in the direction of ensuring the competitiveness of industry sectors and greening production primarily through the development and implementation of modern innovation technologies.
Generation of Hydrogen at a Gas Distribution Station
Authors: Karimova A A , Farukhshina R R , Kuznetsova E A
Published: February 2022

In 2019 the UN announced a course to achieve carbon neutrality of industries by 2050. In this connection interest in hydron fuel has increased. Hydrogen due to its ecological characteristics is considered to be one of the most promising energy sources. It does not pollute the atmosphere, as the product of its combustion is water; it has a high energy intensity and is also the most abundant element on the planet. Despite the fact that most of the hydrogen is produced by the steam reforming of methane, the most environmentally friendly way to produce hydrogen is the electrolysis of water. However, the problem with this method is the high cost of electricity, which in addition in most cases is a product obtained from the combustion of primary energy sources. A modern gas transmission system can become a secondary source of electricity for hydrogen production, thereby solving the problem of utilizing excess pressure energy at gas distribution stations (GDS). The technological solution for using this energy is the installation of turboexpanders and the electrolysis of water at the GDS in order to generate hydrogen.
Development of Mining Assets in the Mining Industry
Authors: Baurina S B , Khudyakov S V , Aleksandrova E V
Published: February 2022

In practice, the industry and the business sector have felt the impact of the coronavirus that has spread around the world. Today it is not known when the system will recover, but it is already quite clear that the post-covid reality will require radically new approaches to the organization of mining operations. Usually, the conservative mining industry in Russia has felt the influence of new trends set by the pandemic, such as, for example, the transition of employees to remote work, which has spurred an accelerated transition to automated work; a change in the distribution chain, are inseparable from the closure of borders, the acquisition of new skills from staff, and others. This article focuses on the development of mining assets in the mining industry. The article concretizes the essence of geometry. Appropriate solutions for end-to-end optimization of the “mine-factory” system are outlined due to a deep understanding of the characteristics of the ore and the introduction of digital tools. The most popular innovations necessary for implementation into the modern mining process have been identified, ranked according to the categories “Production materials, technologies and equipment”, “Automation and digitalization”, “Field development”, “Technologies of deep processing of raw materials: green chemistry”, “Technologies of deep processing “processing of raw materials: green metallurgy”. The production assets of the Polar Division are analyzed using the example of PJSC Mining and Metallurgical Company Norilsk Nickel. As a project initiative to improve the efficiency of ore mining within the mine field, the reconstruction of a skip ventilation shaft from a cage to a skip-cage is being created. A variant of solving the geomechanical problems of the company is being considered.
Finding Ways to Solve Problems of Waste Recycling: Biodegradable Hemp Materials
Authors: Filimonova L , Matys E , Skvortsova N , Valiullina E
Published: February 2022

The importance of polymeric materials in modern life can hardly be overestimated. The annual growth of their production and consumption is one of the main directions of the development of the world economy. At the same time, the problem of recycling polymer waste after the end of the use of products made on their basis arises (according to various sources, only 10-15% of all produced polymers are used for the manufacture of containers). Fully biodegradable plastics are practically non-existent today. Any of the proposed solutions has its own advantages and disadvantages, which require commensuration with consumer characteristics, price, production costs. Independent examinations show that a truly complete degradation of polymers is possible only if they are made from plant materials. The article discusses the rationale for the feasibility of building a plant for the production of biodegradable materials based on plant materials in the Tyumen region.
The Impact of Natural and Climatic Anomalies on the Dynamics of Economic Development
Authors: Solovyev D A , Nefedova L V
Published: February 2022

Crisis events in the economy of the first half of the 21st century are considered as a manifestation of their inevitable cyclicality based on the correlation analysis of statistics of anomalous natural and climatic phenomena. Using spectral analysis methods, the rhythm of these events in the past was investigated, and simultaneously with the use of a specially developed neural model, their cyclical manifestation is predicted for the coming period - until 2049. It is shown that the cyclical nature of natural and climatic phenomena can be considered as one of the economy’s macroeconomic indicators when conducting long-term forecasting of its dynamics.
The Problem of Choice Between Measurement Techniques
Authors: Demyanenko S N , Chechet V A , Redreev G V
Published: February 2022

The assessment of the current conditions of any technical object is based on measurement. Thus, choosing the qualitative descriptor of the object that is to be assessed represents a relatively complex task. This is related both to the informative value of the qualitative descriptor and to the need for applying one or another measurement technique. There are three different ways to deal with the designated task. One possibility is to fix the required level of informative value and choose the measurement technique based on criteria such as the least money expenses for measuring, the shortest measurement duration and the specialization level of the measurement instruments. The second option is to choose specific measurement techniques and obtain the most complete information possible. The third possibility consists in a compromise between the information content of the descriptor and the overall expenses for measurement techniques. By convention, the first option is applied while facing this task, in which the information on the technical conditions of the object is obtained choosing adequate measurement techniques. Determining the value of the structural parameter of the technical conditions is not always possible. The diagnostic parameter, in its turn, is determined by the structural parameters only at a certain level of probability. The producers of machinery are constantly improving their products, upgrading the design of mating parts, changing the properties of wearing surfaces and introducing new materials. As a result, the aforementioned interrelations between the structural and diagnostic parameters are significantly redetermined, whereas the previously engineered diagnostic devices and the implemented methods lead to the ambiguity of the diagnostics. The areas of such ambiguity are here taken into account using a compression vacuum method in order to determine the technical conditions of the sleeve assembly of an internal combustion engine.
Studying the Aspects of Biological Reclamation of Land Located in an Area with a High Concentration of Mining Enterprises
Authors: Yakovchenko M , Izmulkina E , Stenina N , Ivina O
Published: February 2022

The importance of the biological reclamation issue is dictated by changes in the relief, violation of land use and the formation of technogenic landscape as a result of coal mining, both by open and underground methods. Under these conditions, the development of integrated mining and reclamation technologies for the restoration of anthropogenically disturbed agricultural landscapes, aimed at stabilizing the quality and preserving soil resources, is urgent. The article presents an analysis of the use of green technologies to improve the efficiency of land reclamation located in an area with a high concentration of mining enterprises. These studies will allow us to compare and evaluate the possibilities of using different types of plantings in the restoration of anthropogenic territories.
Concept for Construction of Unmanned Ferry Lines on Russia’s Inland Waterways
Authors: Karetnikov V V , Shakhnov S F , Brodsky E L
Published: February 2022

This article considers the prospects of building highly automated ferry lines on the internal waterways of Russia. To do this, the authors used the engineering-cybernetical approach to determine the basic provisions of the concept for the construction of unmanned ferry lines. The key provisions of the concept account for the integration of unmanned ferry lines in the river information and communications triad based on the hierarchical principle: the corporate river information and communications service - the river information service - the automated ship-traffic control system. The authors consider the prospects of using unmanned ferry lines on rivers where the navigation and information support for the unmanned ferry can be provided using radio technical facilities covering both the points of departure and destination. The authors also reviewed the arrangement of unmanned ferry lines for situations where the departure point and the destination are far from each other. This type of unmanned ferry line is suitable for reservoirs or large lakes.

Finally, the research work also provides a rationalization of the selection of the automation level for unmanned ferry lines following the terminology used by the work team for inland water transport of the Committee for the Inland Water Transport of the UN Economic Commission for Europe (UNECE).
Treatment of Wastewater of Small Sewerage Facilities
Authors: Kolpakova V P , Shevtsov M N , Yeremeyeva Yu N , Anapyanova S B
Published: February 2022

The complexity of treating wastewater of small sewerage facilities lies in the small volumes of treated water, considerable irregularity of their inflow to treatment facilities, inhomogeneity of their composition by hours of inflow to treatment facilities, as well as high requirements for treated wastewater discharged usually into low-power water bodies or to the surface. The treatment facilities should exercise the functions of purifying wastewater from pollutants according to regulatory requirements. A sewerage system and wastewater treatment technology have been considered by the example of the town of Fort-Shevchenko. A technology for purifying similar wastewaters using clarifiers with a sludge blanket formed by activated sludge flakes has been proposed. This technology has been introduced at several treatment facilities in the East Kazakhstan region that are successfully operating in compliance with the technical and engineering operation requirements. The treated wastewater quality indicators are given.
Determination of Eigenvalues in Problems on the Buckling of Compressed Rods (Part I)
Authors: Kulterbayev Kh P
Published: February 2022

In many technical academic courses and in the calculations of mechanical design engineers, buckling is a difficult problem. The applied methods of its solution are of a private nature and are unsuitable for modern, more complex structures in such sectors of the economy as mechanical engineering, construction, instrument making, oil and gas facilities, the nuclear industry, power networks, etc. complex problems of the stability of a compressed rod and at the same time achieve greater clarity and versatility with the proposed methods. Using specific examples, the application of the traditional analytical and the proposed analytical-graphic methods is shown. The proposed mathematical models and decision algorithms are verified using computational experiments. Based on the results obtained, practical conclusions are drawn.
Finite Element Study on Forming Metal Sheets with an English Wheel
Authors: Fann K J
Published: February 2022

Because of the application trends of Industry 4.0, small-volume large-variety production becomes the daily life in the manufacturing industry. Techniques to flexibly shape sheet metal parts are therefore more and more inquired. This paper is thus aimed to have a preliminary glimpse at the shaping process made by the English wheel, which is broadly used by craftsmen, via Finite Element Analysis. As a result, the parts shaped by an English wheel with a zigzag path show a curved surface having a homogeneous curvature. The more the impression from the bottom roll onto the sheet metal, the smaller the radius of the bottom roll, and the thinner as well as the more compliant the sheet metal, the larger the curvature of the shaped metal part.
Influence of design parameters on the fresh and durable properties of self-compacting concrete with recycled aggregate
Authors: Martínez-García R , Jagades P , Fraile-Fernández F J , de Prado-Gil J
Published: February 2022

The objective of this paper is to analyse the influence of design parameters on the fresh and mechanical properties in the manufacture of self-compacting concrete with recycled fine and coarse aggregates. Design parameters such as water-cement ratio, water/paste ratio, total aggregate to cement ratio, fine aggregate to coarse aggregate ratio, water to solid ratio in percentage, superplasticiser content, RCA replacement percentage and RFA replacement percentage are analysed. The design parameters are found to affect the evolution of the fresh and mechanical properties of SCC with recycled aggregates.
Microwave Assisted Synthesis of Molybdenum Disulphide/Tungsten Trioxide/Reduced Graphene Oxide (MoS2/WO3/RGO) Nanocomposites for Organic Vapor Sensing
Authors: Gupta Jyoti , Singhal Prachi , Sunita Rattan S
Published: February 2022

Hybrid nanostructures based on two-dimensional (2-D) materials such as transition metal dichalcogenides (2-D TMD’s), transition metal oxides (2-D TMO’s), and graphene are gaining significant attention for their potential application as semiconductor sensing devices owing to their excellent structural, electronic, and optical characteristics. The present work reported 2-D ternary nanocomposites (MoS2/WO3/RGO) as organic vapor sensing material, synthesized using microwave assisted method. Formation of ternary composite system proves to be an efficient strategy to develop novel high performance vapour sensors, providing multiple degrees of freedom and opportunity to exploit the synergistic properties of the resulting material to its full potential for a particular application. The synthesized MoS2/WO3/RGO nanocomposites has been characterized for morphological, and structural analysis through SEM, XRD and FTIR spectroscopic techniques. The electrical and sensing studies of synthesized material is evaluated through IV characteristics using Keithley electrometer. The sensing characteristics has revealed that the synthesized sensor has high sensitivity, good stability at room temperature and outperforms the result obtained from single or binary counterparts. The formation of the heterojunction and electronic modulations at the interface of MoS2, WO3 and RGO results in improved surface charge transfer mechanism and enhancement of sensing performance.
The effect on the tool flank wear width VBmax during turning of Hybrid Mg/(8wt% SiC(p) +2wt% Al2O3(p) +1wt% Gr(p) MMC using PVD coated cermet tool
Authors: Hira Jaspreet , Manna Alakesh , Jha Binit Kumar , Sharma Rohit , Malik Anup , Bhutani Deepak
Published: February 2022

In this study Taguchi Optimization Technique was used, followed by ANOVA to evaluate the machinability i.e. turning of a hybrid Mg/(8wt%SiCp+2wt%Al2O3p+1wt%Grp) MMC using PVD coated cermet tool under the dry turning conditions. Several experiments were conducted using the L27 (313) orthogonal array on NH26 automated lather machine. ANOVA was used to determine the impression of the turning parameter on the VBmax of the tool flank. The finding of the research work investigated that the cutting speed in the dominant factor influence the tool wear width. The confirmation test revealed that the Taguchi technique has been successful in the optimization of the machining parameters for minimum tool wear. The optimal parameter arrangement for minimum tool wear width is at cutting speed of 120 m/min, with the feed rate of 0.4 mm/rev and depth of cut at 0.75 mm. The scanning electron microscope images revealed notches, groves and pits on the tool flank face that is clearly visible at different magnification units. Herein, this paper discuss about several reported synthesis techniques, various characterization techniques used for structural and surface properties identifications, different morphologies and various potential applications of transition metal oxide based nanocomposites.
A study on bi-objective optimization for end milling of Aluminium based composite
Authors: Saini Pardeep , Kumar Deepak , Maurya Anuj K. , Singh Pradeep K.
Published: February 2022

The composites are renowned for better properties than base alloy. In general, 2-8% weight fraction of reinforcement has been researched for various industrial applications. The addition of reinforcement gives improvement in mechanical properties but badly affects ductility. Liquid route method (casting) has been employed for fabrication of SiC reinforced aluminum composites. Machining has been performed by controlling input parameters such as cutting speed, feed rate and depth of cut. Roughness parameter (Ra) and material removal rate (MRR) have been considered for evaluation of surface quality and productivity respectively. Only MRR has been given consideration for rough machining conditions. Whereas, both surface roughness and MRR have been considered for the finish machining conditions. Standard L9 orthogonal array have been employed for the experimentation. The occurrence of hard reinforcement in the base alloy creates the casted composite tough to machine. The confirmation experiments have been performed with the optimal settings of process parameters to confirm the output responses.
Experimental investigation and optimization of weld bead shape factor and form factor using recycled steel slag as a flux in submerged arc welding process
Authors: Saini Sumit , Singh Kulwant , Garg Jatinder
Published: February 2022

The quality and productivity of welds produced depend upon the weld bead profile which is represented by weld penetration shape factor (WPSF) and weld reinforcement form factor (WRFF). The weld profile is further dependent upon welding parameters used hence optimization of welding parameters is essential. In this research work, the steel slag has been recycled to act as a flux in submerged arc welding. The effect of process parameters on WPSF and WRFF using recycled slag has been evaluated. The mathematical models have been developed from the data created. It was found that the weld deposited with recycled steel slag performs well as the WPSF and WRFF are comparable with that deposited with fresh flux. The welding parameters have been optimized using the desirability approach and genetic algorithm. The genetic algorithm yielded more accurate results as compared to the desirability approach.
Static and Dynamic Mechanical Characterization of Polydimethylsiloxane (PDMS) under Uniaxial Tensile Loading
Authors: Kumar David , Singh Sarthak S.
Published: February 2022

The present study is based on performing mechanical characterization of polydimethylsiloxane (PDMS) under tensile loading. PDMS samples are developed by mixing prepolymer and curing agent with 10:1 ratio. Mechanical characterization of the PDMS samples is carried out using static and dynamic mechanical testing methods. In particular, the material is characterized under monotonic loading, different strain rates, and force-controlled cyclic loading. The monotonic loading tests are performed at different grip tightening levels to optimize gripping that avoids slipping and reaches failure point. The strain rate dependency and cyclic loading tests are performed to study the viscoelastic behaviour of the material. Strain rate dependency tests are carried out at the strain rates of 6.7×10-3 s-1, 3.2×10-2 s-1, and 6.2×10-2 s-1. The hysteresis tests are performed at the force rates of 0.1 – 2 N/s. The obtained results show that fixing the testing specimen made of soft hyperviscoelastic material such as PDMS is challenging and can significantly affect its stress-strain behaviour and mechanical properties. A higher strain rate increases the stiffness of the material due to the viscoelastic nature of the material. Observing the stress-strain curves, with respect to the lowest strain rate case, the curve for 6.2×10-2 s-1 strain rate diverges at 40% strain compared to 3.2×10-2 s-1 strain rate curve that diverges at 80% strain. The material shows a nonlinear hysteresis behaviour and similar energy dissipation for the considered force-controlled cyclic loading cases.
Piezoelectric sensor voltage variation with different adhesives at elevated temperature
Authors: Sharma Sukesha
Published: February 2022

Piezoelectric sensors and actuators are used in various applications. They have electromechanical properties. Electric voltage is generated when strain is applied on them and vice versa. These patches can be used at cryogenic temperatures as well as elevated temperatures according to different applications. Piezoelectric patches are pasted on the surface of the structure to sense the vibrations. Different adhesives can be used to paste piezoelectric patches on the structure. In this paper, two different Adhesives, Araldite and Cyanoacrylate are used to paste piezoelectric patches. Two test set up are prepared using two different adhesives. Sensor voltage is obtained from piezoelectric patches at reference temperature and at elevated temperatures. Results are obtained, compared and analyzed. Performance of adhesives is compared at reference temperature and at elevated temperature. Where, Cyanoacrylate is found to be better adhesive to paste piezoelectric patches on the surface of structure as compared to Araldite adhesive.
Xylene sensing using Dy-doped NiO nanoparticles
Authors: Shailja  , Singh K J , Sharma S
Published: February 2022

Present work reports structural and xylene sensing properties of Dy-doped NiO nanoparticles. The samples were prepared using co-precipitation method. XRD pattern reveals incorporation of dysprosium into the host lattice of nickel oxide. SEM images shows the change in morphology from micro-rods to nanoparticles on doping nickel oxide with dysprosium. Raman spectrum reveals the presence of nickel vacancies which serve as adsorption sites for xylene and hence, improves the sensing performance of doped NiO. Doping with dysprosium has not only improved the sensitivity but also enhanced its selectivity towards xylene when tested against ammonia, benzene, ethanol and acetone at 200 °C. Dysprosium doped device has shown sensor response of 7.4 and response (recovery) time of 50 s (36 s), respectively. Our dysprosium doped sensor show improvement in the response and recovery times of already reported xylene sensing devices employing nickel oxide.
Study of electronic structure and transport coefficients of GaN-MoS2 heterostructure
Authors: Khosa Gurpal Singh , Kumar Ranjan , Gupta Shuchi
Published: February 2022

The electronic structure and transport properties of GaN-MoS2 heterostructure have been theoretically investigated using first principles calculations. Among the various possibilities of stacking MoS2 over GaN monolayers to form heterostructure, we studied the case in which the S atom is directly placed over the Ga atom. This type of stacking is energetically favourable. The GaN-MoS2 heterostructure preserves the direct band gap nature of MoS2 monolayer i.e. it has direct band gap of 0.97 eV. The valence bands and conduction bands adjoining the fermi level are mostly contributed by N and Mo atoms. To study the performance of both n-type and p-type GaN-MoS2 heterostructure in thermoelectric applications, we investigate the transport coefficients on which the ZT parameter depends. We found that p-type heterostructure has high electrical conductivity as compared to n-type heterostructure. Due to which it has a high magnitude of power factor which is one of the deciding factors in the evaluation of ZT parameter.
Hyperspectral microscopy imaging based on Fourier ptychographic microscopy
Authors: Zhang Peiwei , Zhao Jufeng , Lin Binbin , Wu Xiaohui , Cui Guangmang
Published: February 2022

Hyperspectral resolution, high spatial resolution, and a wide field of view (FOV) are the targets of optical spectral microscopy imaging. However, hyperspectral microscopy imaging technology cannot provide a wide FOV and a high spatial resolution at the same time. Fourier ptychographic microscopy (FPM) is a novel microscopy imaging technique that uses LEDs at varying angles to capture a series of low-spatial-resolution images that are used to recover images that have both high spatial resolution and a wide FOV. Since FPM cannot obtain the spectral resolution of the sample, in this paper, an efficient strategy based on the FPM system is proposed for the reconstruction of hyperspectral images. First, the traditional FPM setup is optimized, with a new experimental setup based on halogen lamp illumination and a narrow band-pass filter to capture a series of low-spatial-resolution images at different wavelengths. Second, a new algorithm, combining hyperspectral resolution imaging using interpolation compensation and a phase retrieval algorithm, is proposed to reconstruct high-spatial-resolution, wide FOV, and hyperspectral resolution images. Finally, we verified the feasibility and effectiveness of our experimental setup and algorithm by both simulation and experiment. The results show that our method can not only reconstruct high-spatial-resolution and wide FOV images, but also has a spectral resolution of 5 nm.
Nucleation and growth of discontinuous precipitates in Cu–Ag alloys
Authors: An Bailing , Xin Yan , Niu Rongmei , Xiang Zhaolong , Wang Engang , Han Ke
Published: February 2022

To study discontinuous precipitation, which is an important method for strengthening materials, we observed the nucleation and growth of discontinuous precipitates in Cu–Ag alloys using electron backscatter diffraction and scanning transmission electron microscopy. We found that discontinuous precipitation always started with Ag precipitates, which nucleated on Cu grain boundaries. These precipitates then each took the shape of a large, abutted cone that shared a semi-coherent interface with one of the Cu grains, topped by a small spherical cap that shared an incoherent interface with the Cu grain on the opposite side of the boundary. This formation created a difference between the levels of interface energy on each side of boundary. We assume that this difference and boundary curvature together generates the driving force necessary to push grain boundary migration, thus triggering discontinuous precipitation. Because of grain boundary migration, Ag solute was consumed at one side of the grain, which causes a solute difference. The difference produces mainly driving force, pushing the boundaries to migrate forward.
The Effect of Sr composition on the microstructure and mechanical properties of Al-Si-Zn filler for the brazing of AA6061
Authors: Wang Guangyu , Ma Rui , Wan Mingpan , Zhao Fei
Published: February 2022

The microstructure and properties of Al-Si-Zn-Sr filler metals and brazed 6061-T6 aluminum alloy after heat treatment were studied, and the adsorption energy of Sr element on Si (111) surface was calculated. After Sr was added to Al-6Si-40Zn filler metal, its melting range remained unchanged, and the spreading wettability was improved. The microstructure mainly includes α-Al solid solution, fibrous Si, and η-Zn solid solution. Generally speaking, increasing Sr content could improve the average microhardness of brazed joints. The shear strength of the brazed joint containing Al-6Si-40Zn-0.8Sr filler metal was 134.23 MPa, which was 39.3% higher than that of the brazed joint without Sr The calculation results of adsorption energy showed that the surface of Si (111) mainly adsorbed Sr at the vacancy, which changed the growth mode of Si.
Approximate functionals in hypercomplex Kohn–Sham theory
Authors: Su Neil Qiang
Published: February 2022

The recently developed hypercomplex Kohn–Sham (HCKS) theory shows great potential to overcome the static/strong correlation issue in density functional theory (DFT), which highlights the necessity of further exploration of the HCKS theory toward better handling many-electron problem. This work mainly focuses on approximate functionals in HCKS, seeking to gain more insights into functional development from the comparison between Kohn–Sham (KS) DFT and HCKS. Unlike KS-DFT, HCKS can handle different correlation effects by resorting to a set of auxiliary orbitals with dynamically varying fractional occupations. These orbitals of hierarchical correlation (HCOs) thus contain distinct electronic information for better considering the exchange–correlation effect in HCKS. The test on the triplet–singlet gaps shows that HCKS has much better performance as compared to KS-DFT in use of the same functionals, and the systematic errors of semi-local functionals can be effectively reduced by including appropriate amount of the HCO-dependent Hartree–Fock exchange. In contrast, KS-DFT shows large systematic errors, which are hardly reduced by the functionals tested in this work. Therefore, HCKS creates new channels to address to the strong correlation issue, and further development of functionals that depend on HCOs and their occupations is necessary for the treatment of strongly correlated systems.
Isolation and characterization of antioxidative monoterpenes from Cynanchum atratum roots
Authors: Shu Penghua , Yang Yuan , Zhang Hui , Li Nianci , Liu Guangwei , Zhang Jialong , Zhao Qiuyue , Wei Xialan , Yi Wenhan , Sun Na , Xiao Fugang
Published: February 2022

One novel monoterpene rhamnoside (1) and 7 known monoterpenes (2-8) were isolated from the ethanol extract of Cynanchum atratum for the first time. Their structures were identified by comprehensive spectroscopic data analysis such as nuclear magnetic resonance, high-resolution electrospray ionization mass spectra, optical rotatory dispersion, and acid hydrolysis. In the subsequent antioxidant assay, compound 8 exhibited obvious 2,2-diphenyl-2-picrylhydrazyl hydrate radical scavenging activity.
monaLisa: an R/Bioconductor package for identifying regulatory motifs
Authors: Machlab Dania , Burger Lukas , Soneson Charlotte , Rijli Filippo M , Schübeler Dirk , Stadler Michael B
Published: February 2022

Proteins binding to specific nucleotide sequences, such as transcription factors, play key roles in the regulation of gene expression. Their binding can be indirectly observed via associated changes in transcription, chromatin accessibility, DNA methylation and histone modifications. Identifying candidate factors that are responsible for these observed experimental changes is critical to understand the underlying biological processes. Here, we present monaLisa, an R/Bioconductor package that implements approaches to identify relevant transcription factors from experimental data. The package can be easily integrated with other Bioconductor packages and enables seamless motif analyses without any software dependencies outside of R.

Availability and implementation

monaLisa is implemented in R and available on Bioconductor at https://bioconductor.org/packages/monaLisa with the development version hosted on GitHub at https://github.com/fmicompbio/monaLisa.

Supplementary information

Supplementary data are available at Bioinformatics online.
POIBM: batch correction of heterogeneous RNA-seq datasets through latent sample matching
Authors: Holmström Susanna , Hautaniemi Sampsa , Häkkinen Antti
Published: February 2022

Motivation

RNA sequencing and other high-throughput technologies are essential in understanding complex diseases, such as cancers, but are susceptible to technical factors manifesting as patterns in the measurements. These batch patterns hinder the discovery of biologically relevant patterns. Unbiased batch effect correction in heterogeneous populations currently requires special experimental designs or phenotypic labels, which are not readily available for patient samples in existing datasets.

Results

We present POIBM, an RNA-seq batch correction method, which learns virtual reference samples directly from the data. We use a breast cancer cell line dataset to show that POIBM exceeds or matches the performance of previous methods, while being blind to the phenotypes. Further, we analyze The Cancer Genome Atlas RNA-seq data to show that batch effects plague many cancer types; POIBM effectively discovers the true replicates in stomach adenocarcinoma; and integrating the corrected data in endometrial carcinoma improves cancer subtyping.

Availability and implementation

https://bitbucket.org/anthakki/poibm/ (archived at https://doi.org/10.5281/zenodo.6122436).

Supplementary information

Supplementary data are available at Bioinformatics online.
StAmP-DB: a platform for structures of polymorphic amyloid fibril cores
Authors: Louros Nikolaos , van der Kant Rob , Schymkowitz Joost , Rousseau Frederic
Published: February 2022

Amyloid polymorphism is emerging as a key property that is differentially linked to various conformational diseases, including major neurodegenerative disorders, but also as a feature that potentially relates to complex structural mechanisms mediating transmissibility barriers and selective vulnerability of amyloids. In response to the rapidly expanding number of amyloid fibril structures formed by full-length proteins, we here have developed StAmP-DB, a public database that supports the curation and cross-comparison of experimentally determined three-dimensional amyloid polymorph structures.

Availability and implementation

StAmP-DB is freely accessible for queries and downloads at https://stamp.switchlab.org.
Particle filter efficiency under limited communication
Authors: Sen Deborshee
Published: February 2022

Sequential Monte Carlo methods are typically not straightforward to implement on parallel architectures. This is because standard resampling schemes involve communication between all particles. The $$\alpha$$-sequential Monte Carlo method was proposed recently as a potential solution to this that limits communication between particles. This limited communication is controlled through a sequence of stochastic matrices known as $$\alpha$$ matrices. We study the influence of the communication structure on the convergence and stability properties of the resulting algorithms. In particular, we quantitatively show that the mixing properties of the $$\alpha$$ matrices play an important role in the stability properties of the algorithm. Moreover, we prove that one can ensure good mixing properties by using randomized communication structures where each particle only communicates with a few neighbouring particles. The resulting algorithms converge at the usual Monte Carlo rate. This leads to efficient versions of distributed sequential Monte Carlo.
Recurrent evolutionary changes in pollen shape and ornamentation of the vataireoid clade (Papilionoideae, Fabaceae), an early-branching lineage of florally divergent genera
Authors: De Oliveira Débora Cavalcante , Da Costa Moreira André Luiz , Casas Restrepo Luis Carlos , De Lima Haroldo Cavalcante , De Assis Ribeiro Dos Santos Francisco , Cardoso Domingos
Published: February 2022

Pollen traits have clarified the classification and understanding of the evolutionary history of different groups of angiosperms, due to their wide morphological diversity. To increase our knowledge on the morphological evolution of the vataireoid clade (Fabaceae, Papilionoideae), a lineage comprising 30 species of Neotropical trees in the genera Luetzelburgia, Sweetia, Vatairea and Vataireopsis, pollen materials of 26 species were acetolysed and analysed using light and scanning electron microscopy. Characters were defined to reconstruct the pollen evolution in each of the ancestral nodes of the phylogenetic tree of the clade using Bayesian stochastic character mapping. All vataireoid genera have relatively variable pollen morphology, ranging from small to medium and subtriangular to circular amb, and their aperture margo may be present or absent. The exine ornamentation varies greatly across the clade: perforate (L. praecox and S. fruticosa); rugulate (L. andradelimae); rugulate-foveolate-perforate (Vatairea guianensis and Vatairea heteroptera); reticulate (Vataireopsis araroba) and microreticulate in most species. Analyses of ancestral character reconstruction revealed multiple events of independent evolution in all pollen traits during the diversification of the vataireoid clade in the last 16 Myr, since the Miocene. Just as evolutionary transitions in floral architecture were so recurrent in the vataireoid clade, pollen evolution was relatively labile and exhibited little phylogenetic conservatism in shape or ornamentation.
Association Between Statin Use and Daptomycin-related Musculoskeletal Adverse Events: A Mixed Approach Combining a Meta-analysis and a Disproportionality Analysis
Authors: Chuma Masayuki , Nakamoto Aki , Bando Takashi , Niimura Takahiro , Kondo Yutaka , Hamano Hirofumi , Okada Naoto , Asada Mizuho , Zamami Yoshito , Takechi Kenshi , Goda Mitsuhiro , Miyata Koji , Yagi Kenta , Yoshioka Toshihiko , Izawa-Ishizawa Yuki , Yanagawa Hiroaki , Tasaki Yoshikazu , Ishizawa Keisuke
Published: February 2022

Background

There is a growing concern about the association between the combined use of daptomycin (DAP) and statins and the occurrence of musculoskeletal adverse events (MAEs), but this remains controversial. This study aimed to clarify the association between statin use and DAP-related MAEs.

Methods

We used a mixed approach that combines 2 methodologies. First, we conducted a meta-analysis to examine the effects of statin use on DAP-related MAEs. Second, we conducted a disproportionality analysis using the US Food and Drug Administration Adverse Events Reporting System (FAERS) to further confirm the results of the meta-analysis and to examine the effect of each type of statin on DAP-related MAEs in a large population.

Results

In the meta-analysis, statin use significantly increased the incidence of DAP-related rhabdomyolysis (odds ratio [OR]: 3.83; 95% confidence interval [CI]: 1.43–10.26) but not DAP-related myopathy (OR: 1.72; 95% CI: .95–3.12). In the disproportionality analysis using the FAERS, the use of statin significantly increased the reporting OR (ROR) for DAP-related myopathy (ROR: 5.69; 95% CI: 4.31–7.51) and rhabdomyolysis (ROR: 5.77; 95% CI: 4.33–7.68). Atorvastatin, rosuvastatin, and simvastatin all increased the incidence of DAP-related myopathy and rhabdomyolysis.

Conclusion

The mixed approach combining a meta-analysis and disproportionality analysis showed that statin use was associated with the occurrence of DAP-related rhabdomyolysis. The appropriate use of statins and DAP should be performed with careful consideration of its safety.