bluuebunny/crossref_metadata_2025 huggingface dataset:
A network-based microfoundation of Granovetter’s threshold model for social tipping
Authors: Wiedermann Marc , Smith E. Keith , Heitzig Jobst , Donges Jonathan F.
Published: July 2020

Social tipping, where minorities trigger larger populations to engage in collective action, has been suggested as one key aspect in addressing contemporary global challenges. Here, we refine Granovetter’s widely acknowledged theoretical threshold model of collective behavior as a numerical modelling tool for understanding social tipping processes and resolve issues that so far have hindered such applications. Based on real-world observations and social movement theory, we group the population into certain or potential actors, such that – in contrast to its original formulation – the model predicts non-trivial final shares of acting individuals. Then, we use a network cascade model to explain and analytically derive that previously hypothesized broad threshold distributions emerge if individuals become active via social interaction. Thus, through intuitive parameters and low dimensionality our refined model is adaptable to explain the likelihood of engaging in collective behavior where social-tipping-like processes emerge as saddle-node bifurcations and hysteresis.
Microinjection induces changes in the transcriptome of bovine oocytes
Authors: Tan Minjie , van Tol Helena T. A. , Mokry Michal , Stout Tom A. E. , Roelen Bernard A. J.
Published: July 2020

Gene knockdown techniques are widely used to examine the function of specific genes or proteins. While a variety of techniques are available, a technique commonly used on mammalian oocytes is mRNA knockdown by microinjection of small interfering RNA (siRNA), with non-specific siRNA injection used as a technical control. Here, we investigate whether and how the microinjection procedure itself affects the transcriptome of bovine oocytes. Injection of non-specific siRNA resulted in differential expression of 119 transcripts, of which 76 were down-regulated. Gene ontology analysis revealed that the differentially regulated genes were enriched in the biological processes of ATP synthesis, molecular transport and regulation of protein polyubiquitination. This study establishes a background effect of the microinjection procedure that should be borne in mind by those using microinjection to manipulate gene expression in oocytes.
Let-7c regulated epithelial-mesenchymal transition leads to osimertinib resistance in NSCLC cells with EGFR T790M mutations
Authors: Li Xiao-Feng , Shen Wei-Zhang , Jin Xin , Ren Ping , Zhang Jie
Published: July 2020

Epidermal growth factor receptor- tyrosine kinase inhibitors (EGFR-TKIs) have shown promise against non-small cell lung cancers (NSCLCs) in clinics but the utility is often short-lived because of T790M mutations in EGFR that help evade TKIs’ action. Osimertinib is the third and latest generation TKI that targets EGFRs with T790M mutations. However, there are already reports on acquired resistance against Osimertinib. Recent work has revealed the role that miRNAs, particularly tumor suppressor let-7c, play in the invasiveness and acquired resistance of NSCLCs, but the mechanistic details, particularly in Osimertinib resistance, remain elusive. Using two cells lines, H1975 (endogenous T790M mutation) and HCC827-T790M (with acquired T790M mutation), we found that let-7c is a regulator of EMT, as well as it affects CSC phenotype. In both the cell lines, transfection with pre-let-7c led to reversal of EMT as studied through EMT markers e-cadherin and ZEB1. This resulted in reduced proliferation and invasion. Conversely, reduced expression of let-7c through anti-let-7c transfections significantly increased proliferation and invasion of lung cancer cells. Expression of let-7c was functionally relevant as EMT correlated with resistance to Osimertinib. High let-7c expression reversed EMT and made cells sensitive to Osimertinib, and vice versa. WNT1 and TCF-4 were found to be two targets of let-7c which were epigenetic suppressed by let-7c through increased methylation. In vivo, pre-let-7c inhibited while anti-let-7c potentiated tumor growth and WNT1 and TCF-4 were downregulated in xenografts with pre-let-7c. Silencing of both WNT1 and TCF-4 resulted in potentiation of Osimertinib action. Our results suggest an important role of let-7c in regulating EMT and the resulting Osimertinib resistance in T790M NSCLCs. More clinical studies need to be performed to fully understand the translational relevance of this novel mechanism.
AChR antibodies show a complex interaction with human skeletal muscle cells in a transcriptomic study
Authors: Hong Yu , Liang Xiao , Gilhus Nils Erik
Published: July 2020

Acetylcholine receptor (AChR) antibodies are the most important pathogenic marker in patients with myasthenia gravis (MG). The antibodies bind to AChRs on the postsynaptic membrane, and this leads to receptor degradation, destruction, or functional blocking with impaired signal at the neuromuscular junction. In this study, we have explored the effects of AChR antibodies binding to mature human myotubes with agrin-induced AChR clusters and pathways relevant for AChR degradation using bulk RNA sequencing. Protein-coding RNAs and lncRNAs were examined by RNA sequencing analysis. AChR antibodies induced marked changes of the transcriptomic profiles, with over 400 genes differentially expressed. Cholesterol metabolic processes and extracellular matrix organization gene sets were influenced and represent AChR-trafficking related pathways. Muscle contraction and cellular homeostasis gene sets were also affected, and independently of AChR trafficking. Furthermore, we found changes in a protein-coding RNA and lncRNA network, where expression of lncRNA MEG3 correlated closely with protein-coding genes for cellular homeostasis. We conclude that AChR antibodies induce an active response in human skeletal muscle cells which affects key intra- and extracellular pathways.
Regioselective remote C5 cyanoalkoxylation and cyanoalkylation of 8-aminoquinolines with azobisisobutyronitrile
Authors: Wen Chunxia , Zhong Ronglin , Qin Zengxin , Zhao Mengfei , Li Jizhen
Published: July 2020

The C5–H cyanoalkoxylation and cyanoalkylation of 8-aminoquinoline derivatives were achieved with azobisisobutyronitrile under different catalysis systems.
A formal [3+2] cycloaddition reaction of N-methylimidazole as a masked hydrogen cyanide: access to 1,3-disubstitued-1H-1,2,4-triazoles
Authors: Yavari Issa , Khaledian Omid
Published: July 2020

N-Methylimidazole (NMI) can act as a masked HCN in the synthesis of 1,3-disubstitued-1H-1,2,4-triazoles via a formal cycloaddition reaction of hydrazonoyl chloride with NMI.
Simply translating mercury detection into a temperature measurement: using an aggregation-activated oxidase-like activity of gold nanoparticles
Authors: An Pengli , Rao Honghong , Gao Min , Xue Xin , Liu Xiuhui , Lu Xiaoquan , Xue Zhonghua
Published: July 2020

A new household thermometer-based POCT analysis for mercury based on the aggregation-activated oxidase-like activity of gold nanoparticles.
Visible light photoredox alkylazidation of alkenes with sodium azide and heteroarenium salts: entry to azido-containing 1,4-dihydropyridines
Authors: Yang Yuan , Xu Chong-Hui , Xiong Zhi-Qiang , Li Jin-Heng
Published: July 2020

Azido radical-initiated alkene photoredox alkylazidation using heteroarenium salts as alkyl reagents for producing 2-azido-1-(1,4-dihydropyridin-4-yl)-ethanes is depicted.
DMAP and PivOH-promoted amination/allenization reaction
Authors: Zhang Bo-Sheng , Li Yuke , Gou Xue-Ya , Zhang Zhe , An Yang , Wang Xin-Gang , Liang Yong-Min
Published: July 2020

This report described the first DMAP and PivOH-promoted ortho-C–H amination and ipso-allenization reaction of iodobenzenes realized by Pd/norbornene cooperative catalysis.
Fluoroalkyl sulfides as photoredox-active coupling reagents for alkene difunctionalization
Authors: Kosobokov Mikhail D. , Zubkov Mikhail O. , Levin Vitalij V. , Kokorekin Vladimir A. , Dilman Alexander D.
Published: July 2020

A visible-light-promoted fluoroalkylation-thiolation of alkenes is described.
Spatial dynamics of lithiation and lithium plating during high-rate operation of graphite electrodes
Authors: Finegan Donal P. , Quinn Alexander , Wragg David S. , Colclasure Andrew M. , Lu Xuekun , Tan Chun , Heenan Thomas M. M. , Jervis Rhodri , Brett Dan J. L. , Das Supratim , Gao Tao , Cogswell Daniel A. , Bazant Martin Z. , Di Michiel Marco , Checchia Stefano , Shearing Paul R. , Smith Kandler
Published: July 2020

Favorable conditions for lithium plating on graphite electrodes occur at high charge rates, causing accelerated degradation and safety concerns. A detailed map of lithiation and lithium plating dyamics is presented.
Iterative multi-energy calibration and its application in online alloy smelting process monitoring using laser-induced breakdown spectroscopy
Authors: Li Xin , Zhao Tianzhuo , Zhong Qixiu , Nie Shuzhen , Xiao Hong , Zhao Shenghai , Huang Wendi , Fan Zhongwei
Published: July 2020

IMEC: one standard sample, multiple rounds of self-correction, and higher performance.
Speeding up biphasic reactions with surface nanodroplets
Authors: Li Zhengxin , Kiyama Akihito , Zeng Hongbo , Lohse Detlef , Zhang Xuehua
Published: July 2020

The kinetics of a model biphasic reaction at the interface of surface nanodroplets is quantitatively studied. The droplet reaction time scales with ∼Pe−2/3of the reactant flow. Enhanced mass transport contributes to accelerated kinetics.
Anticancer potential of some imidazole and fused imidazole derivatives: exploring the mechanism via epidermal growth factor receptor (EGFR) inhibition
Authors: Kalra Sourav , Joshi Gaurav , Kumar Manvendra , Arora Sahil , Kaur Harsimrat , Singh Sandeep , Munshi Anjana , Kumar Raj
Published: July 2020

Imidazole-based epidermal growth factor receptor (EGFR) inhibitors were computationally designed and synthesized.
A dual-trigger-mode ionic hydrogel sensor for contact or contactless motion recognition
Authors: Wang Qiao , Ding Hongyao , Hu Xiaosai , Liang Xiaoxu , Wang Miaomiao , Liu Qing , Li Zongjin , Sun Guoxing
Published: July 2020

The sandwiched hydrogel capacitive system is designed to fabricate a dual-trigger mode ionic sensor for recognizing mechanical stimuli and diverse touch-free gestures simultaneously, performing high responsivity and accurate spatial resolution.
Detection of Al3+ and Fe3+ ions by nitrobenzoxadiazole bearing pyridine-2,6-dicarboxamide based chemosensors: effect of solvents on detection
Authors: Sudheer  , Kumar Vijay , Kumar Pramod , Gupta Rajeev
Published: July 2020

Hybrid chemosensors, based on a pyridine-2,6-dicarboxamide fragment while containing a 4-nitrobenzoxadiazole group, are used for the sensing of Al3+ and Fe3+ ions where detection was significantly controlled by the selection of a solvent.
Doxorubicin-loaded micelles with high drug-loading capacity and stability based on zwitterionic oligopeptides
Authors: Xue Weili , Trital Ashish , Liu Sihang , Xu Liangbo
Published: July 2020

Scheme of preparing doxorubicin-loaded micelles based on zwitterionic oligopeptides EKCEK.
Self-healing hybrids fabricated by metal complexation with imidazole-containing silsesquioxane nanoparticles
Authors: Sasaki Yusuke , Mori Hideharu
Published: July 2020

Simultaneous achievement of self-healing ability and material hardness in materials is challenging because these properties are contradictory. In this study, we designed self-healing hybrids with tunable flexibility and healing properties.
An approach towards the construction of the tetracyclic skeleton of palhinine alkaloids
Authors: Han Congcong , Chen Yang , Ching Yin-Cheung , Lee Chi-Sing , He Shuzhong
Published: July 2020

A bifunctional Lewis acid catalyzed Diels–Alder/carbocyclization cascade process was developed for the rapid construction of the tetracyclic core of palhinine alkaloids.
A laser etched zinc ion microbattery with excellent flexibility and self-healability
Authors: Du Xiaoyu , Shi Junjie , Chen Zhicheng , Ni Tong , Li Jiaxin , Ruan Limin , Zeng Wei , Cheng Feng , Yue Yang , Wang Siliang
Published: July 2020

Aqueous zinc ion microbatteries (ZIMBs) exhibit excellent flexibility and self-healability.
Snapping elastic disks as microswimmers: swimming at low Reynolds numbers by shape hysteresis
Authors: Wischnewski Christian , Kierfeld Jan
Published: July 2020

An elastic disk with a snapping transition triggered by local swelling swims in a viscous fluid at low Reynolds numbers because of the hysteretic nature of the snapping transition.
Arginine-rich dipeptide-repeat proteins as phase disruptors in C9-ALS/FTD
Authors: Odeh Hana M. , Shorter James
Published: July 2020

A hexanucleotide repeat expansion GGGGCC (G4C2) within chromosome 9 open reading frame 72 (C9orf72) is the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia (C9-ALS/FTD). This seminal realization has rapidly focused our attention to the non-canonical translation (RAN translation) of the repeat expansion, which yields dipeptide-repeat protein products (DPRs). The mechanisms by which DPRs might contribute to C9-ALS/FTD are widely studied. Arginine-rich DPRs (R-DPRs) are the most toxic of the five different DPRs produced in neurons, but how do R-DPRs promote C9-ALS/FTD pathogenesis? Proteomic analyses have uncovered potential pathways to explore. For example, the vast majority of the R-DPR interactome is comprised of disease-linked RNA-binding proteins (RBPs) with low-complexity domains (LCDs), strongly suggesting a link between R-DPRs and aberrations in liquid–liquid phase separation (LLPS). In this review, we showcase several potential mechanisms by which R-DPRs disrupt various phase-separated compartments to elicit deleterious neurodegeneration. We also discuss potential therapeutic strategies to counter R-DPR toxicity in C9-ALS/FTD.
Feedback of molecular outflows from protostars in NGC 1333 revealed by Herschel and Spitzer spectro-imaging observations
Authors: Dionatos Odysseas , Kristensen Lars. E. , Tafalla Mario , Güdel Manuel , Persson Magnus
Published: July 2020

Context. Far infrared cooling of excited gas around protostars has been predominantly studied in the context of pointed observations. Large-scale spectral maps of star forming regions enable the simultaneous, comparative study of the gas excitation around an ensemble of sources at a common frame of reference, therefore, providing direct insights in the multitude of physical processes involved.

Aims. We employ extended spectral-line maps to decipher the excitation, the kinematical, and dynamical processes in NGC 1333 as revealed by a number of different molecular and atomic lines, aiming to set a reference for the applicability and limitations of different tracers in constraining particular physical processes.

Methods. We reconstructed line maps for H2, CO, H2O, and [C I] using data obtained with the Spitzer infrared spectrograph and the Herschel HIFI and SPIRE instruments. We compared the morphological features revealed in the maps and derive the gas excitation conditions for regions of interest employing local thermodynamic equilibrium (LTE) and non-LTE methods. We also calculated the kinematical and dynamical properties for each outflow tracer in a consistent manner for all observed outflows driven by protostars in NGC 1333. We finally measured the water abundance in outflows with respect to carbon monoxide and molecular hydrogen.

Results. CO and H2 are highly excited around B-stars and, at lower, levels trace protostellar outflows. H2O emission is dominated by a moderately fast component associated with outflows. H2O also displays a weak, narrow-line component in the vicinity of B-stars associated to their ultraviolet (UV) field. This narrow component is also present in a few of outflows, indicating UV radiation generated in shocks. Intermediate J CO lines appear brightest at the locations traced by the narrow H2O component, indicating that beyond the dominating collisional processes, a secondary, radiative excitation component can also be active. The morphology, kinematics, excitation, and abundance variations of water are consistent with its excitation and partial dissociation in shocks. Water abundance ranges between 5 × 10−7 and ~10−5, with the lower values being more representative. Water is brightest and most abundant around IRAS 4A, which is consistent with the latter hosting a hot corino source. [C I] traces dense and warm gas in the envelopes surrounding protostars. Outflow mass flux is highest for CO and decreases by one and two orders of magnitude for H2 and H2O, respectively.

Conclusions. Large-scale spectral line maps can provide unique insights into the excitation of gas in star-forming regions. A comparative analysis of line excitation and morphologies at different locations allows us to decipher the dominant excitation conditions in each region in addition to isolating exceptional cases.
TheXMM-Newtonserendipitous survey
Authors: Traulsen I. , Schwope A. D. , Lamer G. , Ballet J. , Carrera F. J. , Ceballos M. T. , Coriat M. , Freyberg M. J. , Koliopanos F. , Kurpas J. , Michel L. , Motch C. , Page M. J. , Watson M. G. , Webb N. A.
Published: July 2020

Context.TheXMM-NewtonSurvey Science Centre Consortium (SSC) develops software in close collaboration with the Science Operations Centre to perform a pipeline analysis of allXMM-Newtonobservations. In celebration of the twentieth anniversary of theXMM-Newtonlaunch, the SSC has compiled the fourth generation of serendipitous source catalogues, 4XMM.

Aims.The catalogue described here, 4XMM-DR9s, explores sky areas that were observed more than once byXMM-Newton. These observations are bundled in groups referred to as stacks. Stacking leads to a higher sensitivity, resulting in newly discovered sources and better constrained source parameters, and unveils long-term brightness variations.

Methods.The 4XMM-DR9s catalogue was constructed from simultaneous source detection on overlapping observations. As a novel feature, positional rectification was applied beforehand. Observations with all filters and suitable camera settings were included. Exposures with a high background were discarded. The high-background thresholds were determined through a statistical analysis of all exposures in each instrument configuration. The X-ray background maps used in source detection were modelled via an adaptive smoothing procedure with newly determined parameters. Source fluxes were derived for all contributing observations, irrespective of whether the source would be detectable in an individual observation.

Results.The new catalogue lists the X-ray sources detected in 1329 stacks with 6604 contributing observations over repeatedly covered 300 square degrees in the sky. Most stacks are composed of two observations, the largest one comprises 352 observations. We find 288 191 sources of which 218 283 were observed several times. The number of observations of a source ranges from 1 to 40. Auxiliary products, like X-ray full-band and false-colour images, long-term X-ray light curves, and optical finding charts, are published as well.

Conclusions.4XMM-DR9s contains new detections and is considered a prime resource to explore long-term variability of X-ray sources discovered byXMM-Newton. Regular incremental releases, including new public observations, are planned.
The data processing pipeline for the MUSE instrument
Authors: Weilbacher Peter M. , Palsa Ralf , Streicher Ole , Bacon Roland , Urrutia Tanya , Wisotzki Lutz , Conseil Simon , Husemann Bernd , Jarno Aurélien , Kelz Andreas , Pécontal-Rousset Arlette , Richard Johan , Roth Martin M. , Selman Fernando , Vernet Joël
Published: July 2020

The processing of raw data from modern astronomical instruments is often carried out nowadays using dedicated software, known as pipelines, largely run in automated operation. In this paper we describe the data reduction pipeline of the Multi Unit Spectroscopic Explorer (MUSE) integral field spectrograph operated at the ESO Paranal Observatory. This spectrograph is a complex machine: it records data of 1152 separate spatial elements on detectors in its 24 integral field units. Efficiently handling such data requires sophisticated software with a high degree of automation and parallelization. We describe the algorithms of all processing steps that operate on calibrations and science data in detail, and explain how the raw science data is transformed into calibrated datacubes. We finally check the quality of selected procedures and output data products, and demonstrate that the pipeline provides datacubes ready for scientific analysis.
Limitations on seismic effects of technological explosions in the combined development of the Sarbai deposit
Authors: Kutuev Vyacheslav , Zharikov Sergey
Published: July 2020

The issue of joint production of drilling-and-blasting operations (DBO) is acute in the combined field workings with the condition of underground mining in the edge massif of the pit walls. Normally, the underground mine construction begins with the quarry depth approaching the end marks. In this situation, even if there is any volume for wall cutback, it is very insignificant and blasting works come closely to the limit circuit of the quarry, behind which the protected massif is located and underground workings is supposed to be carried out in the future. The main task in carrying out DBO under such conditions is to maintain the stability of this massif. Timely explosion shielding and the creation of contour fracture surfaces by applying controlled blasting reduce the negative explosion impact on the edge, yet do not always prevent the stress waves spread across the massif caused by seismic effect. Therefore, limiting the explosion seismic action in the border zone is as important for the massif stability as the professional pre-splitting.
About transition processes in blasthole drilling at quarries
Authors: Regotunov Andrey , Sukhov Rudolf , Bersenyov Gennady
Published: July 2020

As a system, the mining enterprise develops under constantly changing conditions of the external and internal environment. These conditions affect the state of the most important drilling subsystem: blasthole drilling technology, safety, performance, power consumption of the boring rigs and roller bits used. The main transition processes as necessary responses of the subsystem to changing conditions were identified as a result of fragmentary data analysis showing decisions taken over the past 15-20 years, which increase drilling activity efficiency and safety of smaller quarries of Russia, which contain a significant amount of material resources. The main transition processes contribute to the growth of drilling performance and consist of changing the following: bit design for specific rocks; drilling method; drilling mode; boring rig design; controlled parameters of drilling process and rock properties redetermination; parameters of maintenance and repair system. Based on the performed analysis, the systematization results of the main factors predetermining the need for transition processes implementation in the “drilling operations” subsystem were obtained and presented. The proposed approach allowed to reveal a holistic picture of the main interacting factors in the “drilling operations” subsystem. Based on the factors systematization presented in the article it is possible to envisage changes of individual factors depending on changes of other factors, not functionally related directly when planning drilling operations.
Simulation of the preparation and face drilling processes with laser scanning and automated marking of the drilling grid
Authors: Volkova Evgeniya , Druzhinin Aleksey , Kuzminykh Roman , Poluzadov Vladimir
Published: July 2020

The article discusses the methods of calculating the drilling and blasting scheme and constructing a drilling grid, manual and automatic calculation options are compared. A method for automatically constructing a drilling grid based on laser scanning is proposed. Moreover, the proposed method can be implemented using cheap equipment - a laser rangefinder and an Arduino microcomputer. Based on the data of the laser rangefinder with openCV and SciPy libraries, a polygonal 3D model of the face is built. The transfer of the drilling grid to the 3D model is implemented using the bilinear interpolation algorithm. The constructed polygonal model can be improved by making changes to the construction algorithm, since it is developed by the authors and can be further developed. The simulation model is created in Anylogic software and shows the drilling process taking into account the previously calculated drilling pattern. The proposed models can be used as a basis for further research and software development.
Automation of the process of reverse engineering of urban development projects based on the results of aerial photographic operations
Authors: Akulova Elena , Alybaev Aleksandr , Buzina Daria
Published: July 2020

3D models of objects of urban development, created by the results of aerial photographic operations or laser scanning, have high metric accuracy, but require significant labor costs, both in terms of creation and visualization. To construct three-dimensional models that allow the user to perceive information in the usual spatial form, and satisfying the accuracy requirements for solving urban planning problems, it is proposed to automate the reverse engineering process based on the Metashape and ContextCapture software products.
Zoning of town on undermined territory using GIS software
Authors: Zuev Pavel , Vedernikov Andrey
Published: July 2020

for settlements located near mines and quarries, it is often necessary to zoning areas that are affected by mining operations. Most often, their influence is manifested in the form of subsidence of the earth's surface, sometimes sinkholes. It is particularly relevant for the "factory-type" towns of the Urals, where historically industrial settlements developed together and on the basis of mining and metallurgical industries, often having common borders. After decades, and sometimes centuries, the justified and safe use of these territories causes serious problems due to fragmentation and lack of information about their condition. A similar problem was encountered by the Berezovskiy town in the Middle Urals, most of whose territory was undermined. The closure and subsequent flooding of part of the mines of the previously city-forming gold mine led to the need to study its territory. To do this, a method was developed and zoning was performed in a step-by-step manner in the geoinformation system, and the consequences of flooding were established. In the process of implementation, all the engineering-geological, geodetic and other information provided by the mine was used. The results are unique due to the uniqueness and heterogeneity of the parameters of underground workings, sinkholes on the earth's surface caused by workings that are densely located on the studied territory.
The study of the movement of a piece on the camera crushing in network type bases as applied to the workflow of the FCC
Authors: Lagunova Yuliya , Shestakov Victor , Ibrayeva Nazira
Published: July 2020

The paper considers a software-modelling structure for solving the problem of crushing of solid materials, mountain mineral raw materials of different strength and composition. The task is to study the movement of a piece along the crushing chamber of a cone crusher, the stages of destruction of pieces are considered. Setting the main parameters of the FCC, the working process of the crusher and the parameters of the destruction of pieces in the crushing chamber. The study of the basic characteristics of the movement process, the interaction and destruction of pieces is the main aspect of the work process. More precisely, the issues were examined, on the basis of which the dependencies were compiled, which are used in the algorithm of the model of the working process of FCC at the beginning of the cycle of the mode of movement. One of the processes considered in the article is squeezing a piece between the armors with a subsequent decrease in the distance between the armors.
Development of a digital model of the working process of a hydraulic excavator
Authors: Nabiullin Rustem , Komissarov Anatoliy , Shestakov Viktor
Published: July 2020

In this work, we consider a method for determining the rational values of the structural and operational parameters of the lever - hydraulic mechanisms of hydraulic excavators based on an analysis of the results of a computational experiment obtained at the output of a mathematical model of a workflow. It is shown that the presence of kinematic connections between the engine (hydraulic cylinder) and the links of the lever-hydraulic mechanism causes a change in the relationship between the operating parameters of the engine and the power parameters implemented on the driven members (bucket, handle and arrow), depending on the geometric parameters (lengths) of links and coordinates of points (axes) connections links. A simulation model of the working process is developed, which allows to determine the operational parameters of the lever - hydraulic mechanisms.
Development of engineering approach to the assessment of stress raisers in metal structures of dragline excavators
Authors: Pobegailo Petr , Kritsky Dmitry , Suslov Nikolai , Gilmanshina Tatiana
Published: July 2020

In the present work, its authors present the new results obtained on the creation and development of an engineering approach to the assessment of stress raisers in the metal structures of dragline excavators, convenient to be applied in the express diagnostics system to test the condition of such machines. The main result of this work is the conclusion that the value of the geometric stress concentration factor for the fillet weld of metal structures of the excavator arm EH-10/70A under working conditions can be written using the Afanasiev formula.
Analysis of the dependence of the stressed state of the tracked track of a career excavator from an angle slope
Authors: Rakhutin Maxim , Simba Navarrete , Khoroshavin Sergey
Published: July 2020

Conducted static research and determined the strength characteristics of the loaded three-dimensional model of the caterpillar track when working at different slope angles. The parameters were calculated in the 3D modeling system “SolidWorks”. As a result of research, it was found that with an increase in the slope angle, the values of the static equivalent stress and strain in the caterpillar track increase in direct proportion, while the value of the safety factor decreases accordingly.
Heat transfer enhancement of the open-type heat recovery unit
Authors: Davydov Stanislav , Apakashev Rafail , Kokarev Konstantin
Published: July 2020

An increase in the heat transfer efficiency of the open-type heat recovery unit due to the sequential heat and mass transfer enhancement is considered. The graphs of variances in the water temperature, gas temperature, gas enthalpy and gas specific humidity at the end of each site are presented. The proposed designs of the open-type heat recovery unit can be used for the flue gas disposal, including the disposal of natural gas combustion products in the greenhouse facility.
Influence of climatic and hydrodynamic factors on the quarry water purification process from nitrogen compounds
Authors: Khokhryakov Alexander , Studenok Gennady , Studenok Andrey , Olkhovsky Alexander , Boltyrov Vladimir
Published: July 2020

The nitrogen compounds, namely ammonium, nitrite and nitrate nitrogen, are the main substances polluting the quarry and drainage waters of mining enterprises that use the ammonium nitrate-based explosives for drilling-and-blasting rock mass preparation. In accordance with the legislation, such waters are subject to treatment prior to discharge into the water bodies. At the mining enterprises, the promising treatment method is the treated water conditioning in the flooded abandoned open-pit mines, during which the natural microbiological nitrification of ammonium and nitrite nitrogen contained in the quarry drainage waters is performed with an efficiency of more than 95%. The article discusses the influence of natural climatic and hydrodynamic factors on the nitrification process according to the results of a purification process study that has been performed since 2014 until the present time at a large mining enterprise. The relevant conclusions and recommendations are given.
The peculiarities of tourism development as a driver of economic development of the region
Authors: Tsatkhlanova Tamara , Erdnieva Elzata , Ubushaeva Bayrta , Burkutbaeva Namina , Erendzhenova Danara
Published: July 2020

This article is devoted to the disclosure of the essence and structure of the tourist complex as a specific type of socio-economic system at the regional level. The efficient and successful functioning of the economy of any territory as a single economic complex should be accompanied by the improvement of the organization of production structures and the rationalization of its sectoral composition. Thus, the improvement of the tourism sector occupies one of the most important places among a large set of interrelated issues in the development of the regional economy, which is due to the multiplier effect in the development of this industry. The authors analyzed the state, unique characteristics, level of potential and prospects of development of the tourism industry in order to identify the vector of social and economic growth of the region on the example of the Republic of Kalmykia.
Development of regional transport and logistics systems in the transformation of Russia's role in global value chains
Authors: Verbitskaya Natalia
Published: July 2020

This article discusses the transformational capabilities of regional transport and logistics systems in the context of global value chains development, the so-called GVCs (Global value chains) [1], also related to the mining industry in Russia. The GVCs in the world economy are associated with increasing the efficiency of using national economies resources, creating and maintaining new jobs, increasing welfare and political stability, considered in the context of sustainable global development.
Subsurface management model: interdisciplinary approach in conditions of contemporary challenges, risks and uncertainties
Authors: Lebedev Yu.V. , Kokarev K.V. , Gorbunov A.V. , Oleynikova L.N.
Published: July 2020

Difficult environmental, economic, social and political conditions require an in-depth analysis of interdisciplinary relationships at industrial areas. The “Subsurface Management System” is a complex of developed subsoil resource fields characterized by geological, geomechanical and aerogasdynamic processes, and industries linked with each other through flows of energy, matter and information, integrated with civil society and environment. The flow of biogenic elements in subsurface management areas tend to increase the physical flows exporting the elements of biological product flow to the global ocean. The flows of energy in subsurface management areas in form of clean primary production of bioenvironment are changing fundamentally towards expansion of anthropogenic (man-made) factor channel by 8-12%. The flows of environmental information in subsurface management areas contain details about compliance of the environmental conditions with biological regelation. The introduced original term “subsurface management system” accounts for distribution of flows of energy, matter and information between the system components, enabling objective analysis of effective performance of the system and its compliance with sustainable development strategy of industrial areas.
Priorities of innovative activity of Orenburg region's subsoil users
Authors: Novikova Anna , Eremenko Olga , Vashuk Irina
Published: July 2020

.Instability of the global energy market and internal problems of operation of the mature Orenburg oil and gas condensate field have led to the need for innovation. The relevance of new technologies is explained by the fact that since 1967, the development of the field has been complicated by the aggressiveness of the extracted hydrogen sulfide gas and the activity of water manifestations. The lack of effective technologies has led to a deterioration in the conditions of field preparation of raw materials, a drop in reservoir pressure and flow rate of wells, and an increase in their water content. As a result, oil and gas production and environmental and economic efficiency indicators are rapidly declining. In this regard, priorities have been set for technological improvement of subsurface use: 1) reduction of operating costs through the introduction of resource-saving and energy-efficient technologies; 2) application of environmental innovations in order to reduce the man-made impact on the environment. This paper presents measures aimed at solving the identified problems: re-equipment of oil wells with an automated plunger-lift on solar batteries without reconstruction of fountain fittings; arrangement of a system for utilization of gases degassing of sulfur on the Claus process plant;etc.
Determinants of business value increase
Authors: Loginov Aleksandr , Maltsev Nikolay
Published: July 2020

The study is focused on identification of the main indicators promoting increase of business value by way of decomposition of value drivers, depending on used approach to the assessment. The authors analyzed the most common approaches to assessment of business value, identified and generalized the main factors with consideration of indigenous specifics, generated a list of primary indicators of company’s business activities impacting increase of the business value.
Testing a new type of mine brattice and its applications in production units
Authors: Nikolaev Aleksandr , Klishin Vladimir , Maksimov Petr
Published: July 2020

The article describes the ventilation schemes of the potash mine production units, in which, due to the action of natural draughts (thermal depressions), as well as the use of portable mine brattice (MB), safety and energy efficiency of mining operations is increased. The design and test results of a new type of mine brattice capable of quickly and reliably isolating a mine site from the passage of "excess" air (normal ventilation mode) and flue gases (emergency ventilation mode) are given.
Information technologies for landslides and mudflows research
Authors: Biibosunov Bolotbek , Beksulanov Jenish
Published: July 2020

This article presents the results of research using computer technology and mathematical modeling in relation to hydrodynamic processes that determine such natural disasters as landslides and mudflows common in the territory of the Kyrgyz Republic. A specialized website is proposed, which contains the results of scientific research on natural and man-made disasters and exogenous geological processes (EGP). The following systems were used as the main database management systems (DBMS): MS Access, My SQL and PostgreSQL. Thus, the main means of developing computer programs and computational procedures are Delphi, Python, Visual Basic, Java and JavaScript. Web technologies and the following software tools were used to design and create the site: Python, JavaScript, PhP and HTML. Modern level of scientific research presumes and obliges development and using of new information technologies. In this regard there was defined a problem on mathematical modelling and information technologies using for research and forecasting of EGP on the territory of Kyrgyzstan. There are proposed hydrodynamic models and numerical methods of their solution. Information system is developed for landslides, mudflows, and other EGP types, typical for Kyrgyzstan.
2-Aminoquinazolines by Chan–Evans–Lam Coupling of Guanidines with (2-Formylphenyl)boronic Acids
Authors: Jirgensons Aigars , Solomin Vitalii V. , Seins Alberts
Published: July 2020

A new method is presented for the synthesis of 2-aminoquinazolines, which is based on a Chan–Evans–Lam coupling of (2-formylphenyl)boronic acids with guanidines. Relatively mild conditions involving the use of inexpensive CuI as a catalyst and methanol as a solvent permit the application of the method to a wide range of substrates. Nonsubstituted, N-monosubstituted, and N,N-disubstituted guanidines can be used as reactants to give the corresponding 2-aminoquinazolines in moderate yields from readily available (2-formylphenyl)boronic acids.
A Two-Step Synthesis of a Novel 7,8-Dihydro-5,8-ethanoindolizine-6,9(5H)-dione
Authors: Chacón-García Luis , Gallardo-Alfonzo Salvador , Cortés-Garcia Carlos Jesus , Mejía-Farfán Itzel , López Yliana , Mojica Martha , Contreras-Celedón Claudia
Published: July 2020

A two-step synthesis of the novel 5,8-dimethyl-7,8-dihydro-5,8-ethanoindolizine-6,9(5H)-dione from 2,3-dimethyl-1,4-benzoquinone is described. The key step of the synthesis of this unusual fused tricyclic system is the intramolecular regiospecific aza-Michael addition of a pyrrole to an activated double bond by reaction with tetrabutylammonium fluoride under mechanochemical conditions.
Effect of agency costs on the optimal matching grant rate in a model of tax competition with benefit spillovers
Authors: Yang Tong
Published: July 2020

Agency problems arise in any environment involving a principal–agent relationship. This study examines the effect of horizontal fiscal externalities on the optimal matching grant rate in a model where agency costs are inevitable. Because this study takes agency costs into account, the main results should differ from the standard conclusions of the tax competition literature. This study finds that the degree of agency costs and benefit spillovers determine the relationship between tax competition and the optimal matching grant rate. If agency costs are relatively small, and benefit spillover is zero, the optimal matching grant rate should increase with the factors of production demand elasticities with respect to the factor tax rate and vice versa. Tax competition thus may ease the inefficiency arising from agency costs only if the disutility of effort is so large that the benefits from tax competition exceed the costs when benefit spillover is zero.
Kinetic damping of radially localized kinetic toroidal Alfvén eigenmodes in tokamak plasmas
Authors: Shahzad M. , Rizvi H. , Panwar A. , Ryu C. M. , Rhee T.
Published: July 2020

A global eigenvalue solver code is used to analyze the kinetic damping of radially localized kinetic toroidal Alfvén eigenmodes (KTAEs). By including the finite-Larmor-radius effects of ions, KTAEs are found in the Alfvén continuum well above the upper boundary of the TAE gap. The numerical calculations reveal that the real frequency and the kinetic damping of the KTAEs increase with increasing ion Larmor radius, with the ion-Larmor-radius effect intensifying for KTAEs with higher radial mode number. With increasing plasma β, the real frequency of the KTAEs increases whereas the damping rate remains almost constant. At an intermediate plasma β, the real frequencies, damping rates, and mode structures of each pair of KTAEs with radial mode numbers p and p + 1 merge into each other. The damping of KTAEs with lower radial mode number remains unchanged with the tokamak aspect ratio, whereas it increases for KTAEs with higher radial mode number. The KTAEs have lower kinetic damping and a broader mode structure near the core region of a tokamak having a flat core q equilibrium.
Sensitive neutron transverse polarization analysis using a 3He spin filter
Authors: Jau Y. -Y. , Chen W. C. , Gentile T. R. , Hussey D. S.
Published: July 2020

We report an experimental implementation for neutron transverse polarization analysis that is capable of detecting a small angular change (≪10−3 rad) in neutron spin orientation. This approach is demonstrated for monochromatic beams, and we show that it could be extended to polychromatic neutron beams. Our approach employs a 3He spin filter inside a solenoid with an analyzing direction perpendicular to the incident neutron polarization direction. The method was tested with polarized neutron beams and a spin rotator placed inside a μ-metal shield just upstream of the analyzer. No cryogenic superconducting shields or additional neutron spin manipulations are needed. With a counting detector, we experimentally show that the angular resolution δθ=1/(PnAN) rad is only determined by the counting statistics for the total counts N and the product of the neutron polarization Pn and the analyzing power A. With a high-flux neutron beam, 10−6 rad angular sensitivity is feasible within a day. This simple, classical-quantum-limited transverse polarization analysis scheme may reduce the overall complexity of experimental implementation for applications requiring sensitive neutron polarimetry and improve the precision in fundamental science studies and polarized neutron imaging.
Magnetic anisotropy of doped Cr2O3 antiferromagnetic films evaluated by utilizing parasitic magnetization
Authors: Nozaki Tomohiro , Al-Mahdawi Muftah , Shiokawa Yohei , Pati Satya Prakash , Imamura Hiroshi , Sahashi Masashi
Published: July 2020

In Cr2O3 thin films doped with Al or Ir, we have discovered a parasitic magnetization, accompanied by the antiferromagnetic order, with tunable direction and magnitude. In this study, by utilizing the parasitic magnetization, the antiferromagnetic anisotropy KAF of the doped Cr2O3 thin films was evaluated. A much greater improvement of KAF was obtained for Al-doped Cr2O3 films than that of bulk. The maximum KAF in this study was ∼9 × 104 J/m3, obtained for the Al 3.7%-doped Cr2O3 film sample. The enhancement of the magnetic dipole anisotropy KMD due to the site-selective substitution is speculated for the dominant origin of the enhancement. Furthermore, based on the obtained KAF, the influence of the parasitic magnetization on the exchange bias blocking temperature TB of the doped-Cr2O3/Co exchange coupled system was discussed. TB greatly increases when the parasitic magnetization is coupled antiparallel to ferromagnetic moment, such as Al-doped Cr2O3/Co systems.
A state-specific multireference coupled-cluster method based on the bivariational principle
Authors: Bodenstein Tilmann , Kvaal Simen
Published: July 2020

A state-specific multireference coupled-cluster (MRCC) method based on Arponen’s bivariational principle is presented, the bivar-MRCC method. The method is based on single-reference theory and therefore has a relatively straightforward formulation and modest computational complexity. The main difference from established methods is the bivariational formulation, in which independent parameterizations of the wave function (ket) and its complex conjugate (bra) are made. Importantly, this allows manifest multiplicative separability of the state (exact in the extended bivar-MRECC version of the method and approximate otherwise), and additive separability of the energy, while preserving polynomial scaling of the working equations. A feature of the bivariational principle is that the formal bra and ket references can be included as bivariational parameters, which eliminates much of the bias toward the formal reference. A pilot implementation is described, and extensive benchmark calculations on several standard problems are performed. The results from the bivar-MRCC method are comparable to established state-specific multireference methods. Considering the relative affordability of the bivar-MRCC method, it may become a practical tool for non-experts.