bluuebunny/crossref_metadata_2025 huggingface dataset:
The intelligent system for daily nuclear power plants loading control
Authors: Shishkin V A , Danilov A D , Gusev K Yu , Gusev P Yu
Published: November 2020

The average share of nuclear generation in a power balance of Russia approximates 20%, in some parts of a power supply system of the country the contribution of the nuclear power plants (NPP) significantly above. NPP output is increasing (despite the decommissioning of RBMK units) and is provided by the commissioning of capacities of new advanced generation III+ units operating under the Power Delivery Program (power supply contracts). Power unit No. 4 of Beloyarsk NPP, No. 6 and 7 of Novovoronezh NPP, and No. 5 of Leningrad NPP have been commissioned recently. The power unit №6 on the Leningrad NPP will be put into operation in 2020. The dynamic construction of VVER-TOI at Kursk site is underway. An increase in the share of power generated by a nuclear power plant leads to the need for their regulation and frequency response in accordance with the daily load pattern and management of emergency situations in power systems. This means that operation of NPP power units in a load following mode to ensure the stable operation of the power system is a resent challenge. The paper analyzes the existing possibilities of daily control of the plant load, and also proposes to arrange a system of daily loading control of nuclear power plants based on the experience gained.
Theoretical foundations of the application of intergroup interchangeability of the “piston - cylinder liner” connections in the overhaul of engines
Authors: Shkaruba N , Leonov O , Temasova G , Golinitskiy P , Antonova U
Published: November 2020

The article proves that when using ten selection groups instead of five for engines of the Zavolzhsky Motor Plant, an additional wear margin will appear, equal to 12 microns. This will not only lead to an increase in the durability of the connections, but also have a positive effect on such parameters as oil consumption for waste, compression, power, noise, etc. This technology of doubling the selection groups will significantly reduce or completely eliminate work-in-progress, since it is possible to use intergroup interchangeability. Despite the labor costs, with group sorting, it pays off, since the low cost of control pays off with the high quality of the connections.
Prospective recovery of rare earth elements from waste
Authors: Kashurin R R , Gerasev S A , Litvinova T E , Zhadovskiy I T
Published: November 2020

The article provides the fundamental possibility of the associated extraction of Rare Earth Metals during carbonate conversion of phosphogypsum and red muds. There are the isotherms of solubility of carbonates, phosphates and hydroxides of europium, neodymium, holmium, cerium, and ytterbium obtained in carbonate solutions. By changing the carbonation conditions, Rare Earth Elements are transferred to a carbonate solution in the form of water-soluble complexes. Then they can be recovered by precipitation. Also, there were found the optimum conditions with the maximum degree of recovery into the solution.
The optimal profile of wind generator blade modelling with CFD-method
Authors: Khudoyarov Vadim , Samsonenko Dmitry , Nikulin Artyom , Barbashov Nikolai , Abdullina Leila
Published: November 2020

Using of renewable energy sources, instead of traditional oil, gas and coal, is the one of the ways by which it’s possible to hold global warming mechanisms. One of these sources is the wind energy and the device-transformer for it is the wind generator. This paper deals with the problem of the optimal wind generator blade design which allows getting the device efficiency maximum. The alternative wind generators realisations and their advantages are showed in the work. The numerical methods for fluid dynamic equations solving were applied for the optimal profile definition. The advantages of this way were showed, also the model, which was the best fitted for the concerned conditions, was chosen. Modelling was realized in ANSYS Fluent. The results were compared with the real wind generations data.
The analysis the use of intelligent electric networks and Smart Grid systems
Authors: Lukovenko A S , Kukartsev V V , Semenova E I , Leonteva A A , Gek D K , Shagaeva O A
Published: November 2020

Currently, much awareness is paid to the effects of smart grids on efficiency of power systems and energy districts, and the selection of suitable operating modes for equipment for transmitting electric energy. Modern intelligent networks have an impact on ensuring a stable state of power system operation modes, increasing their reliability in operation, and increasing the quality of electric energy. The article analyzes the use of intelligent electrical networks and intelligent network systems in both Western countries and the Russian Federation. Statistical data on electricity consumption and forecast values for this rate of consumption are given. In the future, until 2020-2025, there will be a gradual transition to a new type of electric grid organization - smart grids. The use of electric power systems in conjunction with innovative digital information management systems will significantly change the technical and economic characteristics of future power systems in a positive way. The comparison of technical parameters of traditional and intelligent electric networks, as well as the classification of the main groups of devices controlled (flexible) by AC power transmission systems is carried out. Systems are divided according to the principle of power regulation. Implemented projects of using flexible alternative current transmission system devices in the world are presented. As a result of the analysis, it was found that China is actively developing managed (flexible) AC power transmission systems, with a large amount of investment from the state, the volume of investment is much larger and amounts to about $ 70 billion per year.
Methodological approaches to increase the fault tolerance of software system in multiversion environments
Authors: Losev V V , Kovalev I V , Saramud M V , Testoyedov N A , Lifar A S
Published: November 2020

The article considers the approach to develop of adaptive n-variant software based on versioning. The technological process is presented as a model of functionality. This article proposes approach based on the segmentation of versions functionality. Note that approach is aimed at increasing the unit algorithmic fullness of the version. It is shown that spatially-distributed architecture of model is formed using the proposed approach. The article presents approach to form logical functional levels that is focused on prioritization of functional tasks taking into account the system operational needs.
Effects of drip irrigation regimes on growth, quality plum seedlings, and water use efficiency in European Russia
Authors: Dubenok N N , Gemonov A V , Lebedev A V
Published: November 2020

Currently, there is a lack of capacity in Russia nursery breeding, as a result of which a significant part of the planting material comes from abroad. Drip irrigation is one of the types of resource-saving technologies that make it possible to intensify agricultural production, including in the field of growing planting material for horticulture. The results of the experiment show that for a more rational use of irrigation water and obtaining high-quality planting material of plums in the nursery, it is recommended to use an irrigation regime with maintaining soil moisture in the range of 70-90 and 80-100% of the lowest moisture capacity with a soaking depth in the first year of 30 cm, for the second year - 40 cm, and in the third year - 50 cm. With this irrigation regime, the maximum development of seedlings, their quality and quantity are observed.
Mathematical simulation of the reactor for the ethylbenzene to styrene dehydrogenation reaction
Authors: Solovev S A , Soloveva O V , Gilmurahmanov B Sh , Lamberov A A
Published: November 2020

In this work, we carried out a numerical simulation of an industrial reactor of a radial type with a fixed catalyst bed for the process of ethylbenzene to styrene dehydrogenation. We solved the problem in the approximation of two-dimensional axial symmetry. The parameters of the chemically reacting gas mixture movement in the catalyst bed are considered. The reactor zones which have a negative impact on the reaction efficiency have been determined.
Investigation of collinear acousto-optical diffraction of light fluxes
Authors: Pichugin V N , Lukishin A V , Pakhomova O A , Dubrovina O A , Yagin E V
Published: November 2020

A system of differential equations describing collinear light diffraction on a three-dimensional acoustic Zug of finite length with a sinc-shaped time envelope, where linear frequency modulation is used, is obtained. The obtained solutions of differential equations allow us to describe the longitudinal and transverse distribution of the amplitudes of transmitted and diffracted light under strong acoustic-optical interaction. The dependence of the acousto-optical cell bandwidth on the ratio of the Zug length to the crystal, and the filter transmission during light diffraction on acoustic zugs with a sinc-shaped time envelope is studied. The result of this study can be formulated as the development of analytical and software methods for analyzing diffraction pattern of electromagnetic waves in multi-wave mode of reception on infinitely extended object in free space, as well as a software method for calculating diffraction characteristics at frequencies exceeding the basic frequency, taking into account the inhomogeneity of electromagnetic fields in these conditions. The practical significance is the research results used in the development of a universal technique for design and development of radar systems capable of working adequately in conditions of electromagnetic environment in question. The results of this research will allow a more complete description of the electrodynamic picture of wave propagation and its diffraction, namely, taking into account the diffraction properties of radar systems will allow us to develop a direction for their wider production and distribution.
The method of increasing the reliability of noise immunity when receiving information in radio communication systems of the SHF and EHF ranges
Authors: Lipatnikov V A , Kuzin P I , Rabin A V
Published: November 2020

A fairly large number of methods are known to increase the efficiency of changing the adaptation parameters when receiving information via radio channels, but they have a number of disadvantages. The most significant of them are high energy costs for the transmission of discrete information via radio communication channels and significant time intervals of downtime of radio communication channels, which reduces the noise immunity of transmitted discrete information. The article proposes a new method of noise immunity of radio equipment, taking into account these disadvantages.
Role of sea surface temperature patterns for the Southern Hemisphere jet stream response to CO2 forcing
Authors: Wood Tom , McKenna Christine M , Chrysanthou Andreas , Maycock Amanda C
Published: November 2020

The Southern Hemisphere (SH) eddy-driven jet stream has been shown to move poleward in climate models in response to greenhouse gas forcing, but the magnitude of the shift is uncertain. Here we address the fact that the latest Coupled Model Intercomparison Project phase 6 (CMIP6) models simulate, on average, a smaller jet shift in response to an abrupt quadrupling in CO2 than the predecessor models (Coupled Model Intercomparison Project phase 5 (CMIP5)), despite producing larger global average surface warming. We focus on the response in the first decade when the majority of the long-term jet shift occurs and when the difference between CMIP5 and CMIP6 models emerges. We hypothesise the smaller poleward jet shift is related to the weaker increase in the meridional sea surface temperature (SST) gradient across the southern extratropics in CMIP6 models. We impose the multi-model mean SST patterns alongside a quadrupling in CO2 in an intermediate complexity general circulation model (IGCM4) and show that many of the regional and seasonal differences in lower tropospheric zonal winds between CMIP5 and CMIP6 models are reproduced by prescribing the SST patterns. The main exception is in austral summer when the imposed SST patterns and CO2 increase in IGCM4 produce weaker differences in zonal wind response compared to those simulated by CMIP5/6 models. Further IGCM4 experiments that prescribe only SH extratropical SSTs simulate a weaker jet shift for CMIP6 SSTs than for CMIP5, comparable to the full experiment. The results demonstrate that SH SST patterns are an important source of uncertainty for the shift of the midlatitude circulation in response to CO2 forcing. The study also provides an alternative explanation than was proposed by Curtis et al (2020 Environ. Res. Lett.
15 64011), who suggested model improvements in jet biases could account for the smaller jet shift in CMIP6 models in the extended austral winter season.
Micro-storage State and Mechanism of Shale Gas
Authors: Zhao Tianyi , Peng Zeyang , Chen Gang , Tian Lingyu , Qiao Hui , Li Qianwen
Published: November 2020

Shale gas has attracted increasing attention as a new potential source of natural gas in recent years. Accurate micro-storage and mechanism of shale gas is important for defining and describing the adsorption characteristics, gas-in-place estimates. Organic-rich shale gas reservoirs were usually deposited under water environment which has great impact on shale gas adsorption. Different from the widely used solid-gas interface adsorption theory, the pore system in original shale reservoir is divided into solid-gas system and solid-liquid-gas system. In same statement, shale pores have stronger interaction with water molecules than CH4 molecules, especially in solid-gas system. Water molecules mainly formed as competitive adsorption with shale gas on solid surface (solid-gas system) and liquid water surface (solid-liquid-gas system). Maxim gravitational potential energy, Ψ
max, the distance where Ψ
max occurs, z
m and limited pore side, D
L are given. When pore size D < D
L, no matter in what position the adsorbed molecules is, it force by both sides of the pore silts. When D > D
L, the ratio of unaffected area increases to approximately 100% with pore side. When D < 10 nm, the ratio increases rapidly this means that the ratio of free gas increases quickly. When D > 50 nm, the ratio of unaffected area almost reaches 100%, which means that the content of free gas is far greater than the adsorbed gas. This study not only provides a new classification of shale pore system, but also can act as a reference to better understanding the adsorption mechanism of shale reservoir.
Research on Key Technologies of Data Collection for Energy Storage Power Station Based on “Multi-Station Fusion”
Authors: Wang Peng , Yang Jinsong , Chen Jing , Guo Ruixiang , Yang Desheng , Guo Zheng
Published: November 2020

In view of the current situation of energy storage power station management and data collection, this topic takes the data collection of energy storage power station as the main research object. By analyzing the problems of localized management and inconsistent data collection standards of energy storage power station, an efficient and accurate data collection and lean management mode is explored. It lays a foundation for promoting the construction of “Multi-Station fusion” and provides technical support for the management decision-making of “Multi-Station fusion”.
Analysis of Temporal and Spatial Variations in Actual Evapotranspiration in the Headwaters of the Yellow River Based on Remote Sensing Data
Authors: Dang Suzhen , Guo Xinwei , Zhang Wenge , Yin Huijuan
Published: November 2020

The evapotranspiration product of Global Land Evaporation Amsterdam Model from 1980 to 2017 was used in this study to analyze the spatial and temporal variations of ET in the headwaters of the Yellow River. The results showed that the mean annual ET in the study area was 416.8mm for the period of 1980-2017, increasing gradually from west to east. The ET presented a unimodal distribution, with lower values in January, February, November, and December, and increased significantly from May to September, with the largest ET in July and August. From 1980 to 2017, the annual ET showed a non-significant increasing trend, and the change point for ET is around 2004.
The Applied Research on Bidirectional energy-dissipating damper in High-rise Building Structure
Authors: Wang Ling
Published: November 2020

The bidirectional energy-dissipating damper is applied to the actual engineering structure of a high-rise building. The SAP2000 software was used to establish a three-dimensional model of a high-rise structure, and through the nonlinear dynamic analysis of the structure under the action of an 8 degree earthquake, the effect of the bidirectional energy-dissipating damper on the actual high-rise building structure was studied[1].
Study on Migration and Transformation of Cd in BHMTPMPA Remediation Soil
Authors: Jiang Changjia , Song Jianhui , Cui Shuang , Feng Qi , Li Ping , Shang Liyan , Zhang Qikai
Published: November 2020

Organic phosphonic acid has good chelation ability, easy biodegradation, and belongs to environmental friendly reagent. It can be used as eluent to remediate soil contaminated by heavy metal Cd. This paper studied the migration and transformation process of Cd in organic phosphonic acid BHMTPMPA remediation soil. The results showed that the concentration of exchangeable Cd in 1-7 layer of soil column was significantly higher than that in control, and the concentration of exchangeable Cd in 8-10 layer was not significantly different. The activation effect of BHMTPMPA on Cd in soil column is mainly concentrated in the depth of 0-70 cm soil layer. The exchangeable states in layer 2 Cd the highest concentration, and the exchangeable states in other soil layers Cd no obvious migration occurs, which indicated that the migration mainly occurred in the depth of 0-20 cm soil layer, and the Cd of other forms in the soil column did not occur obvious migration phenomenon.
The effect of manganese(II) on recharge clogging of groundwater heat pump
Authors: Kang Han , Gao Rongyao , Zang Chunyue , Li Dan , Wang Mouwei
Published: November 2020

In order to obtain the mechanism of recharge clogging in the case of manganese ion(Mn2+), the effects of Mn2+ on recharge clogging and microbial community were studied in laboratory sand column. Comparative experiments with four concentrations of Mn2+ were performed. The process of recharge was simulated twice a day, and the daily water flux was detected. The microbial quantity was detected after sand column clogging at 20d, and the microbial structure was analyzed at the end of experiment. The results showed that Mn2+ had little effect on recharge clogging and promoted the growth of microorganisms. The dominant microorganisms in sand column were Flavobacterium sp., Pseudomonas sp., Janthinobacterium sp., and unclassified Comamonadaceae. Manganese ions improved the competitiveness of Flavobacterium sp., but Pseudomonas sp., unclassified Comamonadaceae, Janthinobacterium sp. were inhibited under high manganese concentration.
Effect of Oil Groove Depth on Friction Performance of Copper based Friction Materials with Different Graphite Content
Authors: Du Jianhua , Zhang Nan , Hu Zheng , Ning Keyan , Zhang Wanhao , Han Junjiao , Ji Zhen
Published: November 2020

Copper-based friction materials with different oil groove depth and graphite content were prepared by powder metallurgy process. The effect of oil groove depth on the friction performance of copper based friction materials with different graphite content at different linear velocities was studied. The results show that the dynamic friction coefficient of material decreases with the increase of oil groove depth at low linear velocity of 16.5m/s, and increases with the increase of oil groove depth when linear velocity is ≥ 20m / s. With the increase of oil groove depth and graphite content, the heat resistance of the friction material increases and the wear rate decreases.
An Integrated Process of Reductive Desulfurization by Sodium Borohydride and Its Electroreduction Regeneration in Ionic Liquid
Authors: Shu Chenhua , Liu Xunzheng , Zhu Weihua , Wang Mengjiao , Cai Shuiping , Xie Wenjing , Li Wenting
Published: November 2020

In this study, a novel desulfurization method was developed by introducing ionic liquid (IL) into the integrated process of reductive desulfurization by NaBH4 and its regeneration via NaBO2 electroreduction, where ILs play a dual role of electrolyte and extracting agent. Under the conditions of -2.4 V forward pulse voltage, 0.6 V reverse pulse voltage, 0.6 s forward pulse time, 0.4 s reverse pulse time, 0.8 s turn-off time, 80 min electrolytic time, 4/1 IL/oil volume ratio, sulfur removal reached more than 95% for model fuel oil. Therefore, the novel integrated process of reductive desulfurization by NaBH4 and its electroreduction regeneration in IL is feasible and promising.
Effects of Storage Temperature on the Performance of Sulfonated Scetone-formaldehyde Superplasticizers
Authors: Liu Zunyu
Published: November 2020

Taking temperature as the research object, the effects of different storage temperatures on the performance of sulfonated acetone-formaldehyde superplasticizers (SAF) were studied. The molecular weight of the SAF were characterized by GPC, and disperse performance were evaluated by cement paste fluidity test. The results showed that when the temperature was higher than 40°C, the relative molecular weight of the SAF increased during storage process, and its disperse performance became worse. The influence of storage temperature on the disperse performance of the SAF can be weakened by adding the chain terminator.
A new agent for the treatment of lung cancer: B13 loaded solid lipid nanoparticles
Authors: Çömlekçi Emre , Kutlu Hatice Mehtap , Vejselova Sezer Canan
Published: November 2020

Lung cancer is the leading cause of cancer-related deaths in humans. Recently, the effects of nano-carriers as chemotherapeutic agents on the treatment of lung cancer are in the main focus of cancer research. The use of solid lipid nanoparticles (SLNs) promises high hopes in treatment with the advantages of providing drug localisation in terms of action by both passive and active targeting based on their unique properties, including hydrophilic or hydrophobic loads. SLNs open new limits for long-term and side-specific drug delivery. In this study, a novel SLN of the ceramidase inhibitor, B13 (D-NMAPPD), with modified targeting property was designed, synthesised, and evaluated as potential anticancer agent on human lung cancer cells. Our results implied the efficiency of newly synthesised SLNs on lung cancer in the manner of anti-cancer activity with high cytotoxicity on cancer cells.
Reinvestigation on polarization and strain response of electrically poled lead titanate zirconate ceramics under low-to-medium electric field loading
Authors: Dong Wanjing , Hui Tong , Zhengyi Liu
Published: November 2020

The polarization and strain response of electrically poled lead zirconate titanate ceramics was reinvestigated under low-to-medium electric field loading. A phenomenon that is usually ignored was pointed out and discussed. That is, under low-to-medium cyclic electric field loading, remnant strains measured under a negative electric field loading are larger than those measured under a positive electric field loading. Here, ‘positive’ and ‘negative’ mean that the applied electric field is aligned or antiparallel to the pre-poling direction of the material, respectively. Moreover, a reverse trend was observed for remnant polarizations. Texture-dependent domain switching, defect dipole reorientation, and interactions between them were used to rationalize this phenomenon. In addition, the equation

S

=

d

init

+
α

E

0

⁎
E
±

α
2

E

0

2

−

E

2

,

which is used to describe the strain response, was modified by taking the asymmetry of the electric field versus strain curve into consideration. The modified equation can better describe the strain response than the original equation.
What religion does
Authors: Tweed Thomas A.
Published: November 2020

“What religion does,” continues the discussion of definitions by listing criteria for deciding which one might be most useful, and then it notes that adequate accounts describe not only what religion is but also what it does. At this point a definition is offered that aims to show how religion functions. Religion provides a sense of identity and orientation, and it is a force for social cohesion. It is sticky. It creates bonds within the group, cohesion, and bonds outside the group, adhesion. A socially effective religion will cohere, but not so much as to prevent members from making bonds with those of other faiths. Religion also provides personal meaning and wields social power. As an example of how it exerts power, the chapter examines the way that religion both supported and challenged racial injustice in South Africa.
How religion is expressed
Authors: Tweed Thomas A.
Published: November 2020

“How religion is expressed,” aims to understand how religion functions by looking at how religion is mediated and expressed. Contrary to some writers who have been called mystics, the author suggests there is no unmediated religious experience. Religion is mediated by institutions and technologies, and also by the body and the senses. The brain shapes thinking and feeling. It orients adherents in time and space and shapes how sensory input is classified and how emotions are expressed. The embodied experience of religion is expressed through sound, smell, taste, touch, and sight. Religion is also expressed in diverse cultural forms. There are eight modes of religious expression: experiencing, imagining, making, narrating, conceptualizing, enacting, performing, and gathering.
Global religion today
Authors: Tweed Thomas A.
Published: November 2020

“Global religion today” begins with a snapshot of religion today, when more than eight-in-ten people identify with a religious group. Religion has played an important role in public life since 1945. In the postwar period it was difficult to say whether religion—and the nationalist impulses and industrial economies it sanctioned—was bringing things together or pulling them apart. That question was even harder to answer after the 1970s, when politically assertive religion staged a comeback, global flows intensified, and environmental damage accelerated. At this moment, we face unresolved crises inherited from the colonial and industrial eras—and are bequeathing new problems to those who follow us. However, there are some reasons for hope. Adherents around the world are mobilizing religion’s resources to meet the challenges in this era when we are brought together by fiber optic cables, global consumer culture, and interfaith peace efforts, but also pulled apart by rising nationalisms, climate changes, and holy wars.
The U.S. Civil War: A Very Short Introduction
Authors: Masur Louis P.
Published: November 2020

The US Civil War: A Very Short Introduction covers a period in American history characterized by decades of intensifying conflict over slavery and government authority, culminating in Abraham Lincoln’s election and eleven states seceding from the Union. The Civil War began as a limited conflict with the aim of restoring the Union. It became a diffuse, violent war that lasted four years, claimed hundreds of thousands of lives, and ultimately led to the abolition of slavery and a vigorous debate over the terms by which the seceded states would be restored to the nation. This VSI ends with a chapter on the aftermath of the war and the remaking of America.
4. Structure for catalysis
Authors: Engel Paul
Published: November 2020

‘Structure for catalysis’ details the various patterns of enzyme mechanism and the various structural features helping to achieve catalysis. One of the striking features of enzyme catalysis is substrate specificity. In the lock-and-key hypothesis, the enzyme is viewed as a precisely shaped lock and only the right key, the substrate, can fit and turn it. The lock-and-key combination is the enzyme–substrate complex. A crucial ingredient of the enzyme’s equipment for achieving outstanding catalysis is the ‘catalytic groups’.
Volcanoes: A Very Short Introduction
Authors: Branney Michael J , Zalasiewicz Jan
Published: November 2020

Volcanoes: A Very Short Introduction explains how volcanoes work and how volcanologists forensically decipher the processes involved. Volcanic eruptions are amongst the most dramatic expressions of the powerful tectonic forces at work in the Earth beneath our feet. However, volcanism encompasses much more than just volcanoes themselves. On a planetary scale, it is an indispensable heat release mechanism; shaping landscapes, releasing gases into the atmosphere, and allowing the conditions for life on Earth. Thus, this VSI also considers how volcanoes interact with other physical processes on the Earth, with life, and with human society.
5. Making and breaking volcanoes
Authors: Branney Michael J. , Zalasiewicz Jan
Published: November 2020

‘Making and breaking volcanoes’ addresses how volcanoes are constructed and denuded and explains the shape of volcanoes and their internal architecture, including the differences between scoria cones, tuff rings, maars, and dome fields, shield volcanoes, and stratocones. Some volcanoes (‘monogenetic’ volcanoes) erupt just once, whereas others (‘polygenetic’ volcanoes) may continue erupting intermittently for millions of years. When sufficient magma is rapidly expelled from the shallow reservoirs beneath the volcano the overlying ground is left unsupported and collapses, creating a large topographic basin known as a caldera. As the caldera founders, its steep sides, formed so abruptly, are unstable and collapse inwards as a series of landslides. Tall volcanoes tend to collapse sideways in giant landslides, then grow and collapse again. Rain and meltwater also wears away volcanoes, forming lahars and floods, and choking drainage systems.
8. What have volcanoes done for us?
Authors: Branney Michael J. , Zalasiewicz Jan
Published: November 2020

‘What have volcanoes done for us?’ outlines how humans have benefited from volcanoes. Volcanism has helped make the planet as it is today, by contributing to the chemical composition of the atmosphere and oceans. Volcanoes provide rich, fertile environments for wildlife and agriculture. Ultimately, volcanoes have been essential for the evolution of the biosphere, the emergence of humanity and human civilization, and for the flowering of culture. However, volcanoes across the world are increasingly being exploited for tourism, quarrying, deforestation, and urbanization. They also pose a hazard, one that increases as burgeoning human populations encroach ever closer. The chapter then looks at methods of monitoring and mitigating volcanic hazards.
Giant Magnetoresistive Nanosensor Analysis of Circulating Tumor DNA Epidermal Growth Factor Receptor Mutations for Diagnosis and Therapy Response Monitoring
Authors: Nesvet Jared C , Antilla Katie A , Pancirer Danielle S , Lozano Alexander X , Preiss Jordan S , Ma Weijie , Fu Aihua , Park Seung-Min , Gambhir Sanjiv S , Fan Alice C , Neal Joel W , Padda Sukhmani K , Das Millie , Li Tianhong , Wakelee Heather A , Wang Shan X
Published: November 2020

Background

Liquid biopsy circulating tumor DNA (ctDNA) mutational analysis holds great promises for precision medicine targeted therapy and more effective cancer management. However, its wide adoption is hampered by high cost and long turnaround time of sequencing assays, or by inadequate analytical sensitivity of existing portable nucleic acid tests to mutant allelic fraction in ctDNA.

Methods

We developed a ctDNA Epidermal Growth Factor Receptor (EGFR) mutational assay using giant magnetoresistive (GMR) nanosensors. This assay was validated in 36 plasma samples of non-small cell lung cancer patients with known EGFR mutations. We assessed therapy response through follow-up blood draws, determined concordance between the GMR assay and radiographic response, and ascertained progression-free survival of patients.

Results

The GMR assay achieved analytical sensitivities of 0.01% mutant allelic fraction. In clinical samples, the assay had 87.5% sensitivity (95% CI = 64.0—97.8%) for Exon19 deletion and 90% sensitivity (95% CI = 69.9—98.2%) for L858R mutation with 100% specificity; our assay detected T790M resistance with 96.3% specificity (95% CI = 81.7–99.8%) with 100% sensitivity. After 2 weeks of therapy, 10 patients showed disappearance of ctDNA by GMR (predicted responders), whereas 3 patients did not (predicted nonresponders). These predictions were 100% concordant with radiographic response. Kaplan-Meier analysis showed responders had significantly (P < 0.0001) longer PFS compared to nonresponders (N/A vs. 12 weeks, respectively).

Conclusions

The GMR assay has high diagnostic sensitivity and specificity and is well suited for detecting EGFR mutations at diagnosis and noninvasively monitoring treatment response at the point-of-care.
Area Convergence of Monoculus Robots With Additional Capabilities
Authors: Pattanayak Debasish , Mondal Kaushik , Mandal Partha Sarathi , Schmid Stefan
Published: November 2020

This paper considers the area convergence problem, which requires a group of robots to gather in a small area not defined a priori. While it is known that robots can gather at a point if they can precisely measure distances, we, in this paper, show that without any agreement on the coordinate system, it is impossible for robots to converge to an area if they cannot measure distances or angles. We denote these robots without the ability to measure distances or angles as monoculus robots. We present a counterexample showing that monoculus robots fail in area convergence even with the capability of measuring angles. However, monoculus robots with a weak notion of distance or minimal agreement on the coordinate system are sufficient to achieve area convergence. In particular, we present area convergence algorithms in asynchronous model for such monoculus robots with one of the two following simple additional capabilities: (1) locality detection ($\mathcal{L}\mathcal{D}$), a notion of distance or (2) orthogonal line agreement ($\mathcal{O}\mathcal{L}\mathcal{A}$), a notion of direction. We discuss extensions corresponding to multiple dimensions and the termination. Additionally, we validate our findings using simulation and show the robustness of our algorithms in the presence of errors in observation or movement.
Technical details of the abdominal part during full robotic-assisted minimally invasive esophagectomy
Authors: Berlth Felix , Mann Carolina , Uzun Eren , Tagkalos Evangelos , Hadzijusufovic Edin , Hillegersberg Richard , Li Hecheng , Egberts Jan Hendrik , Lang Hauke , Grimminger Peter Philipp
Published: November 2020

The full robotic-assisted minimally invasive esophagectomy (RAMIE) is an upcoming approach in the treatment of esophageal and junctional cancer. Potential benefits are seen in angulated precise maneuvers in the abdominal part as well as in the thoracic part, but due to the novelty of this approach the optimal setting of the trocars, the instruments and the operating setting is still under debate. Hereafter, we present a technical description of the ‘Mainz technique’ of the abdominal part of RAMIE carried out as Ivor Lewis procedure. Postoperative complication rate and duration of the abdominal part of 100 consecutive patients from University Medical Center in Mainz are illustrated. In addition, the abdominal phase of the full RAMIE is discussed in general.
Left atrial volume stress echocardiography in chronic coronary syndromes
Authors: Morrone D , Arbucci R , Wierzbowska-Drabik K , Ciampi Q , Peteiro J , Agoston G , Varga A , Camorazano A.C , Boshchenko A , Dekleva M , Simova I , Citro R , Colonna P , Lowenstein J , Picano E
Published: November 2020

Background

An enlarged left atrial volume index (LAVI) at rest mirrors increased LA pressure and/or impairment of LA function. A cardiovascular stress may acutely modify LAVI within minutes.

Purpose

To assess the feasibility and functional correlates of LAVI-stress echocardiography (SE)

Methods

Out of 514 subjects referred to 10 quality-controlled labs, LAVI-SE was completed in 490 (359 male, age 67±12 yrs, ejection fraction 60±10%) with suspected or known chronic coronary syndromes (n=462) or asymptomatic controls (n=28). The utilized stress was exercise in 177, vasodilator in 167, dobutamine in 146. LAVI was measured with the biplane disk summation method. SE was performed with the ABCDE protocol. In a single center sub-study in 50 subjects, including 28 controls and 22 patients, also peak longitudinal atrial strain (PALS, %) was measured as an index of LA reservoir function.

Results

The intra-observer and inter-observer LAVI variability were 5% and 8%, respectively. Δ-LAVI changes (stress-rest) were negatively correlated with resting LAVI (r=−0.271, p<0.001), heart rate reserve (r=−0.239, p<0.001), and Δ-PALS (n=50, r=−0.374, p=0.007).LAVI-dilators were defined as those with stress-rest increase ≥6.8 ml/m2, a cutoff derived from a calculated reference change value above the biological, analytical and observer variability of LAVI. LAVI dilation (see figure) occurred in 56 patients (11%). At multivariable logistic regression analysis, B-lines ≥2 (OR: 2.586, 95% CI =1.1293–5.169, p=0.007) and abnormal left ventricular contractile reserve (OR: 2.207, 95% CI=1.111–4.386, p=0.024) were associated with LAVI dilation.

Conclusion

LAVI-SE is feasible, with high success rate and low variability, in patients with chronic coronary syndromes. A wet (increased B-lines) and weak (reduced LV contractile reserve and LA reservoir function) heart frequently portends LAVI dilation during stress.

Figure 1

Funding Acknowledgement

Type of funding source: None
Functional correlates of left atrial volume dilatation during vasodilator stress echocardiography
Authors: Prota C , Ciampi Q , Cortigiani L , Campagnano E , Morrone D , D'Andrea A , Manganelli F , Colonna P , Wierzbowska-Drabik K , Rodriguez Zanella H , Djordjevic-Dikic A , Citro R , Villari B , Carpeggiani C , Picano E
Published: November 2020

Background

Exercise and dobutamine stress may induce acute left atrial volume index (LAVI) dilatation in 1 out 10 patients. The effect of vasodilator stress in LAVI remains unknown.

Purpose

To assess the feasibility and functional correlates of LAVI change during dipyridamole stress echocardiography (SE).

Methods

We studied 149 patients (99 male, age 66±10 years, ejection fraction 59±8%, 64 with previous myocardial infarction), who underwent dipyridamole ABCDE-SE. LAVI was measured with the biplane disk summation method at rest and peak stress: LAVI-dilators were defined as those with stress-rest increase ≥6.8 ml/m2. Criteria for abnormal response of ABCDE-SE were: stress-induced changes in regional wall motion abnormalities (RWMA) for step A; B-lines at peak stress ≥2 for step B (4-site simplified scan, each site scored from 0= A-lines or black lung to 10= white lung for coalescing B-lines); reduced left ventricular contractile reserve (LVCR, peak/ rest based on force) ≤1.1 for step C; abnormal coronary flow velocity reserve (CFVR) ≤2.0, assessed by pulsed wave Doppler sampling in left anterior descending coronary artery for step D; abnormal heart rate reserve (HRR, peak/rest heart rate) ≤1.22 for step E.

Results

LAVI dilation occurred in 13 patients (9%). The positivity was for step A: RWMA in 6 pts (4%); step B: presence of peak B-lines in 12 pts (8%); step C: abnormal LCVR in 14 pts (9%); step D: reduced CFVR in 17 pts (11%) and step E: abnormal HRR in 46 pts (31%). LAVI dilators showed significantly higher incidence of positivity of steps A-B-C-D (see figure) compared to patients without LAVI dilatation.

Conclusion

Evaluation of LAVI change during vasodilator SE is feasible, and LAVI dilatation is more frequently found with ischemic (step A), wet (step B), weak (step C) and cold (step D) heart.

Figure 1

Funding Acknowledgement

Type of funding source: None
Long term perspective with LBBB: role of stress echocardiography
Authors: Dedic S , Boskovic N , Giga V , Tesic M , Aleksandric S , Jovanovic I , Hadzi Tanovic L , Mihajlovic Varbusova I , Stojicic M , Beleslin B , Djordjevic Dikic A
Published: November 2020

Background

Previous studies have shown that left bundle branch block (LBBB), as a relatively common electrocardiographic (ECG) abnormality, represents the condition with often non benign and sometimes adverse outcome.

Purpose

The Aim of our study was to determine the predictive value of a stress echocardiography test in patients with LBBB.

Methods

Our study population included 189 patients (88 male, 46.6%, mean age 63.08±9.65) with diagnosed left bundle branch block who performed stress echocardiography (SECHO) according to Bruce protocol. Median follow-up of the patients was 56 months (IQR 48–71 months) for the occurrence of cardiovascular death and non-fatal myocardial infarction, repeat revascularization (coronary artery bypass grafting-CABG or percutaneous coronary intervention-PCI).

Results

Out of 189 patients, 32 (16.9%) patients had positive, while 157 (83.1%) patients had negative SECHO test. During the follow up period 28 patients had major adverse cardiac event: 1 nonfatal myocardial infarction, 6 heart failure hospitalizations, 5 CABGs, 8 PCIs, while 8 patients had cardiac death. Using the Cox regression analysis, univariate predictors of adverse cardiac events were diabetes mellitus (HR 4.530 [95% CI 1.355–15.141], p=0.014), PCI (HR 4.288 [95% [95% CI 2.010–9.144], p<0.001) and positive SECHO test (HR 2.289 [95% CI 1.006–5207], p=0.048). In the multivariate analysis only previous PCI remained independent predictor of adverse events (HR 3.650 [95% CI 1.665–8.003], p=0.001). p=0.048). Using the Kaplan-Meier survival curve the patients with negative SECHO had better outcome compared to patients with positive SECHO (140/160; 87,5% vs 21/29; 72.4%, p=0.035) and much longer event-free time (77.4±1.6 months vs 67.1±5.4 months, Log Rank 4.136, p=0.042)

Conclusion

Patients with LBBB and negative SEHO test have good prognosis. Patients with history of CAD and diabetes mellitus and LBBB are at increased risk for future events and need periodical reassessment.

Funding Acknowledgement

Type of funding source: None
Speckle-tracking during dipyridamole stress echocardiography in the detection of myocardial ischemia in patients with suspected coronary artery disease
Authors: Moderato L , Pastorini G , Lazzeroni D , Monello A , Rusticali G , Piepoli M.F , Villani G.Q , Binno S
Published: November 2020

Background

The aim of this study was to investigate the incremental value of global longitudinal strain (GLS), postsystolic strain index (PSI) and prestretch (PSE) by automated function imaging with respect to wall motion (WM) and coronary flow reserve (CFR) for the diagnosis of significant coronary artery disease (CAD) during dipyridamole stress echocardiography.

Methods

We retrospectibely enrolled 227 patients with known or suspected CAD, approaching our echo lab to perform a DSE; all patient underwent coronary angiography within 1 month for clinical reasons. Obstructive CAD was defined as the evidence of >70% stenosis during coronary angiogram. Obstructive CAD was detected in 143 (63%) patients, while 84 (37%) had no significant CAD.

Global longitudinal strain, PSI and PSE were measured at rest and peak of the stress (after 6 minutes of 0,84mg/kg of dipyridamole infusion).

Results

Patient with CAD showed a significantly lower GLS at rest (−16.9±4.2 vs −18.6±3.4; p<0.01) and peak (14.9±3.8 vs −21.50±3.3; p<0.01) Figure A; the behavior of GLS was opposite, in patient with CAD showed an increase while in patient without CAD a significant decrease after dipyridamole infusion. There was also a significant difference between groups for Delta PSI (PSIpeak − PSIrest) and Delta PSE (PSEpeak − PSErest), respectively 126±145 vs −40±97, (p<0.01) and 108±163 vs −41±106 (p<0.01) Figure C. ROC analyses produced a statistically valid model: Average GLS at peak (p 0.001; AUC=0.906, cut-off value −18%, sensitivity 83% and specificity 82%); on the basis of these results, we compared WM and myocardial deformation analysis and GLS was superior to CFR LAD, Delta EF, Delta ESV and Delta WMI (Figure B).

Conclusions

GLS, PSE and PSI show an opposite response to dipyridamole, in patients with CAD in patient without CAD and show much higher sensitivity and specificity compared to the conventional parameters like WMI, EF and CFR in detecting CAD

Funding Acknowledgement

Type of funding source: None
Impact of 2016 ASE/EACVI recommendations on evaluation of left ventricular diastolic function and clinical outcomes in patients with diabetes and hypertension without prior adverse cardiac events
Authors: Foo D , Lam K.H , Igo M , Bujang M.A , Ku M.Y , King T.L , Yeo L.S , Ahip S.S , Sahiran M.F , Mustapha M , Michael J , Abdullah A , Fong A.Y.Y
Published: November 2020

Background

Left ventricular diastolic dysfunction (LVDD) has been shown to be more prevalent in patients with diabetes, and once progress to overt heart failure, carry worse clinical outcomes, compared to those without diabetes. The complexity of previous 2009 ASE/EACVI algorithms makes diastolic function (DF) assessment challenging. Hence, prognostic value of LVDD estimates in clinical setting is not well-established.

Objective

To evaluate the impact of 2016 recommendations in estimates of LVDD and predicting cardiovascular outcomes in patients with diabetes and hypertension.

Materials and methods

A total of 111 patients with diabetes and hypertension who attended diabetic clinic follow-up at the primary healthcare settings were enrolled. All patients were clinically NYHA Class I, had no prior adverse cardiac events, and had preserved left ventricular (LV) ejection fraction on echocardiography at screening. Echocardiography was performed to obtain parameters of LV dimensions, LV volumes and LVDD. Both 2009 and 2016 algorithms were applied in DF assessment. All patients follow-up at 1 year to assess clinical outcomes.

Results

There were 65 (58.6%) female patients. Mean age was 59.86 (7.45); mean duration of diabetes was 10.5 (5.41). 55 (50.5%) patients had LV hypertrophy on echocardiography.

Prevalence of LVDD (14.4% vs 55.0%) and elevated LV filling pressure (9.0% vs 26.1%) were lower with 2016 compared with 2009 recommendations. Prevalence of indeterminate DF was 18.0% and 12.6% according to 2016 and 2009 recommendations respectively. Concordance between 2016 and 2009 recommendations was fair (k=0.29, p<0.001), with a reclassification rate of 45.9%.

None out of 45 patients who were diagnosed with indeterminate and normal DF according to 2016 and LVDD with 2009 algorithms developed MACE at 1 year. Out of 12 patients diagnosed with LVDD based on both 2016 and 2009 recommendations, 4 patients developed MACE at 1 year. 2016 recommendations showed better accuracy (sensitivity=80.0%; specificity=88.68%) than 2009 recommendations (sensitivity=80.0%; specificity= 45.28%) in predicting MACE at 1 year.

Conclusions

The application of 2016 recommendations results in lower prevalence of LVDD. The 2016 criteria detect more advanced cases and predict 1 year cardiovascular outcomes better. Further studies are warranted to investigate the prognostic impact of this criteria.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Institute of Health (NIH), Ministry of Health Malaysia