bluuebunny/crossref_metadata_2025 huggingface dataset:
A three‐stage economy optimization method for the aggregator based on electric vehicle user response volumes
Authors: Lin Hui , Zhou Yichen , Li Yonggang , Zheng Haoyang , Yang Yang , Zhen Xinghao , Bian Zhaoyuan , Yue Ziyi
Published: August 2023

With the development of intelligent distribution networks and the proposal of the carbon peaking and carbon neutrality goals, the importance of demand‐side management for the improvement of flexible power operation systems is becoming increasingly prominent. To solve the problems of the excessive peak–valley load differences, the insufficient utilization of demand‐side resources, and the unreasonable pricing of aggregators, this paper proposes a three‐stage economy optimization method for the aggregator based on EV(electric vehicle) user response volumes. To gain the advantages of different types of EVs while increasing the dispatchable capacity, the contract mode between the aggregator and EVs is divided into three categories: complete dispatching, rolling reward and punishment mechanism dispatching, and free dispatching. Based on the cloud model, considering loss aversion, the user's own time flexibility, and the impact of the tariff set by the aggregator on the user's decision‐making, we introduced indicator weights to obtain the improved cloud model. Based on the improved cloud model, a user response volume model is obtained. Then, the aggregator performs a three‐stage pricing optimization operation for EVs based on the bid‐winning peak shaving capacity. In the first stage, the attraction between EVs and charging stations is determined based on the law of gravity, and the charging and discharging reward electricity price is set. In the second stage, the dynamic electricity price of three types of EVs and the charging punishment electricity prices of the rolling reward and punishment mechanism dispatching type are determined. In the third stage, the electricity price of the rolling reward and punishment dispatching EVs is further optimized based on their lack of peak shaving capacity. The method proposed in the paper has been verified to be effective in increasing aggregator profits, increasing EV dispatch capacity, and reducing EV charging costs through the example analysis.
Wideband circularly polarised antenna with dual‐fed strategy simplification based on common mode and differential mode
Authors: Luo Yang , Chen Zhan , Hu Zhipeng , Li Changjiang
Published: August 2023

A novel circularly polarised (CP) antenna design, termed differential mode (DM) and common mode (CM) design, is presented with equal‐amplitude in‐phase feed (EAIPF) in this article. At first, the CM and DM of the antenna are excited separately using the dual ports. Then, the CP antenna is obtained with EAIPF by adjusting the radiation amplitude of CM and DM, due to the orthogonality with a 90° phase difference for CM and DM. Finally, the obtained operational bandwidth of the presented antenna is 1.75–2.30 GHz (27.1%), with a reflection coefficient < −10 dB and axial ratio <3 dB. This CP antenna design eliminates the need to design 90° phase shifter as well as reduces the complexity of the feed structure of CP antennas, providing a novel idea for the design of CP antennas.
Significant enhancement of dielectric properties in polyimides with sulfonyl groups in the side chains
Authors: Luo Jinpeng , Tong Hui , Cao Shimo , Liu Junbiao , Li Xiaomin
Published: August 2023

Polymer dielectrics with excellent thermal resistance and superior energy storage behaviour are extensively demanded with the increasing development of film capacitors applied in hostile environments. In this study, novel diamine with sulfonyl‐containing side chain was designed and synthesised. The corresponding polyimide (PI) dielectrics derived from the sulfonyl‐containing diamine were prepared, so were the polyimides possessing the same backbone but without side chains. Consequently, superior thermal resistance of glass transition temperature ranged from 162–208°C was obtained. Moreover, the polyimides presented permittivity of 3.34–5.89 at 1 kHz, Weibull breakdown strength of 377–538 MV/m and discharged energy density of 3.82–5.85 J/cm3. In particular, sulfonyl‐containing polyimide of SPI‐2 with flexible backbone and sulfonyl side chain indicates the highest discharged energy density and charge‐discharge efficiency simultaneously. The introduction of the strong polar sulfonyl group in the side chain enhances dielectric and energy storage properties effectively. In addition, it is found that the dipolar moment density (μ/Vvdw) calculated from molecular simulation is closely correlated to permittivity measured from experiments. The combined method of molecular simulation and experiments would offer an effective approach to assist in molecular design of high‐performance polymer dielectrics.
Modified indirect rotor field‐oriented control strategies for wye‐connected three‐phase induction motor drives under an open‐phase fault
Authors: Yousefi Bahman , Ghanbari Mahmood , Ebrahimi Reza , Jannati Mohammad
Published: August 2023

Field‐oriented control (FOC) has been broadly used as an accurate control method for electric drives. The traditional FOC approach has been effectively developed to 3‐phase induction motor (3φ IM) drive systems in recent decades. Despite the usefulness of FOC methods during normal condition, these strategies are unable to control a wye‐connected 3φ IM (3φ IMy) under the stator winding open circuit fault (SWOCF). This paper discusses modified indirect rotor FOC (FOCIR) strategies for 3φ IMy drives under the SWOCF. The stationary reference frame (RF) model is presented and utilized to develop vector control systems for the faulty 3φ IMy using asymmetrical transformations. This model is also used to propose a modified FOCIR method for 3φ IMy drives against the SWOCF based on the symmetrical/traditional transformation and using the bi‐voltage controller. The performances of the presented control methods are confirmed via simulations and experiments for a 3φ IMy considering the SWOCF. The achieved results show the effectiveness of modified FOCIR strategies for vector control of the faulty 3φ IMy drive.
New insight on filamentary charge‐loaded flows originated by pulsating glow‐type unipolar coronas in atmospheric air
Authors: Lattarulo Francesco
Published: August 2023

The diffusional process involving elastic collisions between charge carriers and neutrals has long been the predominant candidate for post‐injection momentum loss in the far wider drift region outside confined DC corona discharges in gases. A supplementary research paradigm is here put forward for the interest of a greater understanding of corona‐assisted unipolar ion flows in atmospheric air. In this respect, the auto‐pulsing mode of glow‐type coronas in air is modelled as a source of momentum whose conservation is substantially preserved across the external transfer region. The tangible prospect of charge‐bearing flows in the form of a filamentary convection, with negligible drifting component, in buffer gas is put forward in relation to spontaneous symmetry‐breaking instability. This setting bears some resemblance to the self‐organised collective behaviour of self‐propelled (active) particles. The value of this scheme gains strength precisely in relation to the strong inhomogeneity of the electric field surrounding electrodes prone to go into corona. On such a basis, it is believed that the drift of corona‐generated ions deserves to be reconsidered in view of the arguments set out in the present modelling.
HCS background magnetic field study HYTARO+
Authors: Arrazola D. , Blanco J. J. , Hidalgo M. A.
Published: August 2023

Context. HYTARO+ is an analytical model developed to evaluate the influence of the solar magnetic dipole in the topology of the local structure of the heliospheric current sheet (HCS).

Aims. Statistical methods such as MVA, which are typically used in the study of the HCS come with two limitations. On one hand, they do not provide any information about the physical properties of the current sheet and, on the other, they do not offer the possibility of defining the local structure of the HCS from the physical conditions that prevail in the two sectors that separate the sheet. HYTARO model describes the interaction between the magnetic field that defines the structure of the current sheet and the plasma confined within it. HYTARO+ goes deeper into the study of the background magnetic field that is included in the HYTARO model with the aim of identifying its source.

Methods. Multipole expansion is used to provide a general approach to any physical phenomenon of some system, thereby allowing for a potential function representation. In our case, we considered the dipolar and quadrupolar Sun magnetic field contribution in the HCS.

Results. In the development of the HYTARO+ model, we estimated the components of the dipole and quadrupole magnetic fields at 1 AU. In the present study, we establish that the Z component of the dipole field and the X component of the quadrupole field are the more relevant terms of the background field present in the data that correspond to the discontinuities. A summary of the contribution of the multipolar components along the 23 solar cycle is incorporated.
Ensuring the seismic resistance of operated CHP buildings
Authors: Bellendir E.N , Rubin O.D. , Antonov A.S. , Baklykov I.V. , Zyuzin R.S.
Published: August 2023

The main structures of the engine room of the CHP are among the most responsible reinforced concrete structures, since during operation they are subjected to significant technological loads, including those not provided for by the project. One of the most significant impacts is seismic. During the long-term operation of the CHP, the building structures have experienced significant alternating loads. As a result, the thermal power plants built 45-60 years ago and currently in operation have a reduced level of seismic resistance. As recent events in Turkey have shown, ensuring the safe operation of power plants is a key task. However, new construction is expensive and not always justified, in this regard, the task is to ensure the seismic resistance of existing power plants in seismically hazardous areas.
Analysis of risks arising at the stages of production, transportation, installation of large-sized modules in the design position
Authors: Ambartsumyan Sergey , Mochalin Dmitry , Avetisyan Robert , Siebeva Julia
Published: August 2023

The paper considers the prospects for the development of large-sized modular housing construction in the face of industrial and managerial risks. The authors consider the risks identified at the time of production of a large-sized module, transportation and installation in the design position. The risk planning management algorithm is considered. The article identifies the factors that arise at the stage of production, transportation, installation of a large-sized module in the design position. A literary analysis was carried out on the topic of large-sized volume-block housing construction. The technical and economic prerequisites for the construction of buildings from large-sized modules and obtaining an economic effect are considered, in comparison with the construction of similar buildings in a large-panel or monolithic design. An algorithm for studying potentially significant factors is considered. Practical experiments were carried out, which made it possible to determine the risks affecting the quality of large-sized modules. The task of this work is to identify risks that affect the quality of large-sized modules at various stages: production, transportation, installation of a large-sized module in the design position. As a result, risks were identified by three groups for further qualitative and quantitative analysis, response planning, monitoring, and risk management. The relevance of the considered topic lies in the implementation of investment projects, in their implementation in the field of management.
Logistic indicators of locomotives of diesel traction in Marokand-Kattakurgan section of Uzbek railway
Authors: Ablyalimov Oleg , Avdeyeva Anna
Published: August 2023

The results of a study on the substantiation of the parameters of the logistical indicators of rail freight traffic implemented by diesel locomotives of the UzTE16M3 series when moving with stops on the hilly-mountainous section of Marokand -Kattakurgan of the Uzbek railway are presented. The research methodology is a graphical method for solving the differential equation of train movement in the accepted range of changes in the mass of the composition of freight trains as a result of the implementation of which the authors obtained complete and reduced kinematic parameters of the movement of freight trains per one kilometer of the railway track and the parameters of the logistic indicators of the energy efficiency of these diesel locomotives in the form of tabular data, graphical dependencies, as well as regression equations with the subsequent development of nomograms for their calculation. The results of the study can be used by specialists of the Bukhara locomotive depot, which will allow them to develop recommendations for saving diesel fuel by the diesel locomotives under study, considering various conditions for organizing rail transportation of goods.
Preface
Authors: Uzakov Gulom , Abdullozoda Ramazon , Bovtrikova Elena , Gibadullin Arthur , Toshmamatov Bobir , Morkovkin Dmitry , Sadullozoda Shahriyor
Published: August 2023

Within the framework of the presented material, the results of the conducted VI International Conference on Actual Problems of the Energy Complex and Environmental Protection (APEC-VI-2023).
Identification of parameters of power transformer models using artificial intelligence methods
Authors: Alyunov A N , Vyatkina O S
Published: August 2023

A large number of tasks for analyzing the state of power transformers are solved on the basis of mathematical models, the validity of which is undeniable. The disadvantage of standard methods for diagnosing current-carrying parts of transformers is the requirement to remove voltage. The applied diagnostic methods without stress relief require improvement in terms of increasing accuracy, speed and ensuring predictive response. The paper presents methods for identifying the parameters of mathematical models of power transformers using artificial neural networks.
Results of the calculation of the absorber temperature in a flat solar air heater
Authors: Abbasov Yorqin , Umurzakova Muyassar , Sharofov Salokhiddin
Published: August 2023

The article discusses a method for calculating the temperature of the solar air heater absorber under conditions of still air in the collector and under conditions of low forced convection. The problem of determining the temperature of the air heater absorber tst is considered for the climatic conditions of Fergana, with a horizontal collector and when solar radiation passes through double glass. It is assumed that over the considered short period of time, the temperature of the absorber is constant and the heat loss through the insulation of the bottom of the collector is negligible. Solar radiation passes through ordinary transparent colorless glass with a reflectance of 8%. Taking into account the losses of the heat flux of solar radiation when passing through glass 1 and 2 by the reflection coefficients K1 and K2, in the first version the Stefan-Boltzmann equation is solved, as a result of which the temperature value of the absorber surface is obtained. In the second variant, the absorber temperatures were obtained taking into account convection.
Insulating joints as a destabilizing factor in the operation of the track circuit
Authors: Tarasov Evgeny , Nadezhkin Vadim , Nadezhkina Snezhana , Zolkin Alexander , Popova Elena , Zhuravleva Irina
Published: August 2023

The role of railway transport in the modern economy is highlighted in the article. Directions for improving automation and telemechanics devices have been determined: the creation and implementation of modern devices for monitoring track occupancy of a new type, as well as increasing the reliability of track devices to a large extent, and putting into operation systems for interval regulation of train traffic. The importance of such an element of the railway infrastructure as a rail circuit is also determined. The authors of the work revealed the function of track circuits. In addition to this, the article presents an information diagram of the search for failures in an extensive rail circuit of electrical centralization. The concept of a decision device is disclosed. Possible expressions of the Bayes criterion are also considered. A priori probabilities of finding rail lines are singled out. As a result, a decision rule is revealed that leads to the minimization of the average damage.
Causes of corrosion cracking of pipe metal and methods for their protection
Authors: Garifullina Gulnaz
Published: August 2023

The article is devoted to studying the problem of corrosion cracking of pipelines and methods of their protection. An analysis of the main factors that determine the phenomenon of corrosion cracking is given. The article deals with the issue of identification of corrosion cracking based on the “carbonate theory”. The main methods of protection of metal structures from corrosion cracking are given.
Derivation of the equation of state for a superionic conductor
Authors: Rakhymbekov A Zh
Published: August 2023

The purpose of this article is an analytical consideration of the features of the physical characteristics of the quantities of a hightemperature ceramic solid oxide superionic conductor, using the example of an oxygen pump made of stabilized zirconia. Based on the consideration of an elementary axial section of a superionic tube with geometric data on the length, thickness, and diameter of the tube, an equation was obtained that relates all adjustable quantities of an oxygen pump in the entire range of oxygen dosing, in particular, to select the geometric dimensions of the device and the optimal ratios of controlled quantities. The derivation of such an equation for the pumping section of an oxygen pump is based on a number of assumptions as for an idealized oxygen pump. The currentvoltage characteristic of an oxygen pump in the region of deep pumping, associated with the appearance of electronic conductivity of the ceramics of the pumping section of the oxygen pump, leading to its destruction, electrochemical aging or degradation, has been studied. It is substantiated that the volt-ampere characteristic of the oxygen pump is the only informative curve, which is used to judge the correct mode of operation of the superionic pump and prevent the onset of electrochemical degradation. When developing a research method and setting problems for a ceramic oxide superionic conductor, a number of assumptions were taken into account, as for an idealized electrolyte. The considered solid oxide superionic conductor or solid electrolyte is a ceramic material in the form of tubes, test tubes, tablets, initially containing impurity cations of lower valence, such as calcium, yttrium, scandium, than zirconium. It is these impurity cations that create the presence of vacancies or holes in the solid cubic structure of zirconium dioxide. Through these vacancies, under the influence of external factors, high temperature and direct current electric field, only oxygen anions will be transported. The research method is based on the measurement of the electromotive force, which is recorded at the boundary section: air/electrode/superionic, unambiguously related mathematically to the oxygen concentration in the air flow. Mathematical formulas are given for calculating the desired oxygen concentration depending on various external conditions. Theoretical conclusions and substantiations on the possibility of using the phenomenological transport properties of a superionic conductor under production conditions are presented.
Diverse analysis method and its application to identify vulnerabilities of emergency protection of sodium generation boilers
Authors: Gorobchenko Stanislav , Kovalev Dmitriy , Taraban Maria , Krivonogova Alexandra , Voinash Sergey , Sabitov Linar , Kiyamov Ilgam
Published: August 2023

The paper considers the possibility of assessing the development of accidents on the basis of a system-functional approach applied to the analysis of the probability of accidents in soda recovery boilers (SRBs). The main attention is paid to identifying the most vulnerable elements of the SRB and the possibility of diagnosing and preventing accidents based on the development of diagnostic systems in the existing APCS systems of the most important section of the SRB - the black liquor combustion system.
EcoGIS-Simulation Software for riverbed sediments modeling
Authors: Khrapov Sergey , Agafonnikova Ekaterina , Potaptseva Polina , Makoveev Ilya , Klikunova Anna
Published: August 2023

The paper describes the EcoGIS-Simulation software and hardware complex for numerical hydrological modeling of river systems. The computing core makes it possible to carry out a non-stationary self-consistent calculation of the dynamics of surface and groundwater, as well as the transfer of entrained and suspended sediments. The main attention is paid to the organization of geoinformation support for such calculations at the stages of preparation of initial data, processing of results and their visualization. EcoGIS-Simulation software is designed to simulate non-stationary self-consistent dynamics of surface and groundwater together with the transport of entrained and suspended sediments. The strong dependence of the nature of sediment transport on the particle size in the conditions of the Medveditsa River in the vicinity of the city of Mikhailovka (Volgograd Region, Russia) is shown.
Promising technologies of coal ash and slag waste recycling
Authors: Korolev Michael , Totok Irina , Mesyats Maria
Published: August 2023

Coal ash and slag waste are the products of coal processing that can be recycled into other useful products, but most part of them is accumulated in dumps which causes several environmental consequences. The paper presents a review of the most promising ways of coal ash and slag waste processing based on patent analytics and scientific literature review. Since the patenting process usually comes before innovation implementation, this approach allows to identify the most promising technologies even if they haven’t been implemented yet.
Phytochemical composition of the underground part of Paeonia tenuifolia L. and leaves of Petrocoma hoefftiana (Fisch.) Rupr.
Authors: Kvashin Vadim , Tsakhkhaeva Zukhra , Shamarina Marina , Toguzova Anna , Morozova Elizaveta
Published: August 2023

The phytochemical composition of plants is very diverse and includes many biologically active substances, and their combination determines the pharmacological activity. This article examines the phytochemical composition of the underground part of Paeonia tenuifolia L. and leaves of Petrocoma hoefftiana (Fisch.) Rupr. It was found that the studied objects contain glycyrrhizic acid, peucedanin, flavonoids, phloroglucides, tannins, ascorbic acid. The studied plants can be considered as a new type of plant raw materials, promising for further study.
Research of bittern concentration processes lake Karaumbet and Barsakelmes
Authors: Otakuziyev Ziyodullo , Absattorov Diyorbek , Rifky Mohamed , Rakhimkulov Shokir , Usmanov Ilkham , Ramazonova Dilbar , Matkarimov Zaynobiddin , Samadiy Murodjon
Published: August 2023

The conducted studies on the concentration of brine from lakes Karaumbet and Barsakelmes under conditions close to industrial ones showed the possibility of obtaining practically pure sodium chloride and magnesium chloride melt. To do this, the evaporation process must be carried out in two stages. The evaporation to a density of 1.550 g/sm3 increases the content of magnesium chloride from 7.20% to 28.24%. At the same time, the content of sodium ions decreases from 8.05% to 0.91%. The evaporation at the first and second stages must be carried out to a density of 1.340-1.345 g/sm3, which contributes to the release of sodium chloride into the precipitate. The evaporation of the mother liquor makes it possible to obtain practically pure sodium chloride. The content of magnesium chloride after evaporation in the first stage is 15-16%.
Dendroclimatic studies of aspen growth in Moscow
Authors: Lipatkin Vladimir , Rumyantsev Denis , Vorobyeva Natalia , Sirotova Anna
Published: August 2023

This article presents the results of studying aspen (Populus tremula L.) growth in urbanized environment of Moscow metropolis with the help of dendrochronology method. Four significant correlation coefficients for data of two aspen chronologies and the group of forty-eight meteoparameters of current calendar year and the calendar year which was previous to the year of tree ring formation were established by the dendroclimatic method. According to the results of correlation calculation it was established that correlations sustainable for both considered chronologies as well as biologically interpretable ones between radial growth fluctuations and climatic data fluctuations are absent. It is due to the fact that the aspen trees on considered plots are in the conditions near the optimum zone and the factors, which are limiting radial growth size, change from year to year. One year one factor has strong deviation from optimal for species parameters, and another year it will be another factor. In this case the correlation analysis gives results about the lack of correlation, but it does not mean that climatic factors have no impact on tree ring formation. The absence of correlation, for instance, to the temperatures observed in May of the current year is important as this is a period of great cambium activity and assimilation biomass forming. So, the increase in temperature of this month, probably predicted with global warming, will not have a negative effect on aspen growth in the conditions of the studied stands.
To the study of block lithospheric structures of seismically vulnerable zones in the region
Authors: Mukhin A S , Pavlova A V , Telyatnikov I S
Published: August 2023

The paper describes a method for using regional seismic data based on processing the results of experiments carried out using a tiltmeter to study dangerous seismic conditions and clarify the structural boundaries of lithospheric units in the region. The use of experimental methods will make it possible to determine the true parameters of the block structure, which are necessary for the practical application of the block element method in the study of regional seismicity.
Plants of the calcifilic flora exposition of the N.V. Tsitsin Main Botanical Garden of the Russian Academy of Sciences, listed in the regional Red Data Books of Central Russia
Authors: Shustov M V , Mamontov A K , Zueva M A , Stogova A V
Published: August 2023

The results of conservation of plants of the exposition of the calciphilous flora of the Main Botanical Garden of the Russian Academy of Sciences, listed in the regional Red Data Books of Central Russia, are shown. For 12 years, in the culture of GBS RAS, in the conditions of Moscow, 118 calciphilous species listed in the regional Red Books, represented by 77 genera from 34 families, were studied. Among them, in terms of introduction resistance, resistant ones prevail - 46% and highly resistant - 35.5%, weakly resistant - 13.5%, unstable - 5%. The main groups according to ecological confinement are considered: obligate (25%) and facultative (75%) calciphilic species. The experiment proved the importance of using special agricultural techniques for the successful adaptation of representatives of this group. In total, an average of 70% of calciphilous taxa of regional protected lists were tested. The representation of calciphilic species in the regional Red Data Books of Central Russia is different and is due to the natural features of the distribution of their classical habitats. In the regions of the Chernozem region, this figure ranges from 55% in the Belgorod region to 24% in the Tambov region. In the Non-Chernozem region: Bryansk, Ryazan, Tula regions, calciphilic species in relation to the total number of protected species also represent a significant part - 25%. For Vladimir, Ivanovo, Kaluga, Kostroma, Smolensk, Tver, Yaroslavl regions and the federal city of Moscow, calciphilic taxa represent an average of 9% of protected lists. The share of calciphilous species of categories: 0, 1, 2 in the regional Red Data Books of Central Russia averages 58%, which indicates a high vulnerability of this group and the need for ex situ study
Study on proppant settlement and migration in a single microfracture
Authors: Lv Sen , Liu Chen Wei , Zeng Xu , Yan Silin , Li Haojia
Published: August 2023

Micro-fractures are widely developed in deep shale gas reservoirs after fracturing. Effective support of micro-fractures is of great significance to slow down the production decline rate of shale gas Wells. When the particles enter the fracture, they can be effectively supported to provide a channel with high conductivity for oil and gas transport. The level of conductivity depends on the distribution of proppant in the fracture, so it is very important to analyse and describe the settlement, migration and placement of proppant. Therefore, based on CFD-DEM method, this paper systematically studied the migration and placement of proppant in a single rough micro-fracture, and explored the influence of related factors.
Dynamic Access Control Through Cryptography in Cloud
Authors: M Sankari , KS Kamatchi , T Venketbabu , G Sangeetha , D Sheema
Published: August 2023

In recent days, enabling encrypted access control to hosted data is attractive to organizations and many users in untrusted cloud. However, an efficient encrypted progressive access control system designing in the cloud remains a challenge. This paper proposes DAC in cryptographic, for effective access control that provides practical encryption in the system. DAC in cryptography removes permission by designate to update the encrypted data in cloud. DAC in cryptography includes file encryption with a well- formed key list that document a file key and a set of lock keys. A dedicated administrator is required to replace a new revocation key by comparing the previous key. Revocation requires a dedicated administrator to upload a new revocation key to encrypt files with the new encryption level and update the encryption key list accordingly in cloud. DAC in cryptography proposes a three-key technique to limit the key list size and later on encryption. As a result, change in access control is enforced using DAC in cryptography. This improves efficiency by not requiring high decryption or re-encryption and to upload or re-upload of large quantity of data by the administrator and assures security by revoking permissions immediately. It demonstrates the construction safety and efficiency using formalization framework and system implementations.
Derivation via Hamilton's principle of a new shallow-water model using a color function for the macroscopic description of partial wetting phenomena
Authors: Delacroix Bastien , Bouyges Maxime , Blanchard Ghislain , Laurent Claire , Villedieu Philippe
Published: August 2023

This paper presents a new shallow-water type model suitable for the simulation of partially wetting liquid films without the need for very fine resolution of the contact line phenomena, which is particularly suitable for industrial applications. This model is based on the introduction of a color function, propagated at the averaged velocity of the bulk flow, and equal to one where there is a liquid film and zero in the dry zone, which implies a non zero gradient only at the interface. This approach has the advantage of easily locating the interface, allowing to model macroscopically the forces acting at the contact line, which is essential for the simulation of partial wetting phenomena. The formal derivation of this model is based on the principle of least action known as Hamilton's principle. Here this principle is applied in a full Eulerian form to derive the complete system of equations with the color function. This method proves to be particularly suitable for this type of development and as an illustration it is also applied to recover another model proposed by Lallement et al. [39, 73]. Finally, both models are compared from a theoretical point of view and the advantages of the new color function based model are discussed.
Developmental dysplasia of the hip is common in patients undergoing total hip arthroplasty under 50 years of age
Authors: Muddaluru Varun , Boughton Oliver , Donnelly Thomas , O’Byrne John , Cashman James , Green Connor
Published: August 2023

Introduction: Developmental dysplasia of the hip (DDH) refers to congenital and/or developmental hip instability that can result in hip joint subluxation or dislocation. When detected neonatally, conservative treatment with hip bracing can restore normal hip anatomy. Missed detection of DDH in the neonatal period or late development of DDH often requires surgical intervention to correct the abnormal anatomy. Furthermore, despite surgical intervention, residual sequelae may persist leading to early osteoarthritis of the hip joint requiring joint replacement surgery. Aim: This study investigates the prevalence of hip dysplasia in patients undergoing total hip arthroplasty (THA) under 50 years of age. Methods: The hip arthroplasty database at a national referral centre was investigated from January 2014 to December 2020. In patients under 50 years of age, those with an adequate pre-operative anteroposterior pelvic radiograph without previous hip arthroplasty were included, while those with inadequate radiographs were excluded. The following measurements were made on the contralateral non-operated hip: (1) lateral centre-edge angle (LCEA), (2) Tönnis angle, (3) acetabular version, (4) acetabular depth, (5) femoral head lateralisation, (6) femoral head extrusion index, and (7) acetabular depth-to-width ratio. Results: In total, 451 patients were included in this study. Twenty two percent of the patients had hip dysplasia, based on a LCEA of <25° and 42.6% of patients had hip dysplasia, based on a Tönnis angle of > 10°. The mean LCEA and Tönnis angle were 31.47 ± 9.64 and 9.82 ± 6.79°, respectively. Conclusion: Hip dysplasia is common in patients undergoing THA under the age of 50 years with over 40% having dysplasia according to the Tönnis angle. Classification of primary and secondary osteoarthritis in the joint registries will benefit our knowledge on the prevalence of DDH in the adult population.
Krebstherapien und Herzrhythmusstörungen – worauf muss ich achten?
Authors: de Wall Claudia , Berliner Dominik , Duncker David
Published: August 2023

Im Rahmen onkologischer Therapien ist das Auftreten von nahezu allen bradykarden und tachykarden Herzrhythmusstörungen beschrieben. Die Arrhythmien können Auswirkungen auf die
Krebsbehandlung haben und lebensbedrohliche Ausmaße annehmen. Die Kenntnis des Nebenwirkungsprofils der eingesetzten Substanzklassen ist bedeutsam für das Monitoring der Patienten. Oftmals
werden QTc-Zeit-verlängernde Substanzen verabreicht. Eine QTc-Zeit von > 500 ms geht mit einem erhöhten Risiko für ventrikuläre Tachykardien einher und bedarf eines strukturierten
Vorgehens gemäß neuer ESC-Leitlinie. Ein Absetzen der lebenswichtigen Krebstherapie sollte der letzte Schritt sein. Die bei Vorhofflimmern etablierten Scoring-Systeme zur
Risikostratifizierung sind für Krebspatienten nicht validiert, sodass vor Einleitung einer oralen Antikoagulation eine individuelle Nutzen-Risiko-Abwägung erfolgen sollte.
Riechtraining mit ätherischen Ölen nach Geruchsverlust
Authors: Thumm Anusati
Published: August 2023

Störungen des Geruchssinns zählen zu den häufigen Begleiterscheinungen einer viralen Infektion. Aber auch mit zunehmendem Alter oder bei gewissen neurologischen Erkrankungen nimmt die Riechfähigkeit des Menschen ab. Ein gezieltes Training mit ätherischen Ölen kann helfen, die Nase zu reaktivieren und die Lebensqualität der Betroffenen deutlich zu verbessern.
Heiserkeit
Authors: Welsch Katja , Stern Cornelia , Schreiber Thomas , Lorenz Daniel
Published: August 2023

Die Autoren stellen jeweils eine Behandlungsstrategie gegen Heiserkeit vor.
Ganzheitliche Beratung bei Krebserkrankungen
Authors: Irmey György
Published: August 2023

Krebs ist von seinem Verlauf als chronische Erkrankung in den vergangenen Jahren besser verstanden worden. Sowohl Personen, die über lange Zeit mit Therapien und Maßnahmen sowie den resultierenden Einschränkungen leben, als auch Patientinnen und Patienten, die nach relativ kurzer Behandlung geheilt werden, profitieren von einer aktiven Haltung. Schlüsselfaktoren sind dabei die erlebte Selbstkompetenz und Selbstwirksamkeit, aus denen Patientenkompetenz wachsen kann. In diesem Zusammenhang ist die Arzt-Patienten-Beziehung von tragender Bedeutung. Mit der Erforschung der Lebensstilfaktoren Entspannung, Ernährung und Bewegung in ihrem Einfluss auf die Krebserkrankung haben Therapeuten viele Hebel, die sie bewusst neben ihren therapeutischen Maßnahmen in die Hände ihrer Patienten geben können. Die Gesellschaft für Biologische Krebsabwehr e. V. (GfBK) berät Personen, die von einer Krebserkrankung selbst betroffen sind, und deren Angehörige und Ärzte. Anlässlich des 40. Jubiläums der Gesellschaft im vergangenen Jahr wurde eine Umfrage bei den Mitgliedern – die meisten davon Krebspatienten – wie auch bei den Berater und Ärzte durchgeführt. Die für die therapeutische Beratungspraxis wichtigsten Ergebnisse werden hier fokussiert angesprochen.
Akzeptanz und Nutzermotivation einer Digitalen Alkohol
Nachsorge App (DANA) bei Rehabilitand:innen mit
Alkoholgebrauchsstörungen
Authors: Liekefett Leander , Rumpf Hans-Jürgen , Bischof Gallus
Published: August 2023

Ziel Digitale Behandlungskonzepte haben das Potenzial, die
Behandlungslücke bei Menschen mit Abhängigkeitserkrankungen zu
verringern, wenn entsprechende Angebote für die Zielgruppe als attraktiv
wahrgenommen werden. Zugleich ist die Akzeptanz und Nutzungsmotivation
entsprechender Angebote in der Zielpopulation bislang unzureichend
untersucht.

Methodik Auf Grundlage einer Literatursuche wurde Elemente
telemedizinischer und Nachsorgebausteine als Bestandteile einer fiktiven
digitale Alkohol-Nachsorge-App („DANA“) beschrieben und
konsekutiv rekrutierte Patient:innen (n=102) einer
Alkoholentwöhnungseinrichtung nach mittels standardisierter
Fragebögen zu ihrer Akzeptanz und Nutzungsmotivation der jeweiligen
Bausteine befragt. Bei 96 Patient:innen mit vollständigen bzw.
plausiblen Antworten wurden die Einflüsse von Geschlecht, Alter und
Selbstwirksamkeitserwartung auf die Nutzungsmotivation analysiert.

Ergebnisse Faktorenanalytisch konnten zwei Dimensionen identifiziert
werden, die als „Lebensstilförderung“ und
„Selbst- und Fremdkontrolle“ interpretiert werden konnten. Die
Analyse von Subgruppen ergab, dass jüngeres Alter auf beide Dimensionen
und höhere Selbstwirksamkeit auf die Dimension
„Lebensstilförderung“ einen signifikant positiven
Einfluss auf die Akzeptanz- und Nutzermotivation haben. Das Geschlecht der
Patient:innen beeinflusst nach dieser Studie die Akzeptanz und Nutzermotivation
nicht signifikant. Mehrheitlich wurde von den Patient:innen eine Kombination von
persönlicher und digitaler Nachsorge als attraktiv eingestuft.

Diskussion Digitale Nachsorgeangebote weisen bei Patient:innen mit
Alkoholabhängigkeit als Addendum zu persönlicher Nachsorge hohe
Akzeptanz auf, insbesondere bei jüngeren Zielgruppen.
Machine Learning for Decision-Support in Acute Abdominal Pain – Proof of Concept and Central Considerations
Authors: Henn Jonas , Hatterscheidt Simon , Sahu Anshupa , Buness Andreas , Dohmen Jonas , Arensmeyer Jan , Feodorovici Philipp , Sommer Nils , Schmidt Joachim , Kalff Jörg C. , Matthaei Hanno
Published: August 2023

Acute abdominal pain is a common presenting symptom in the emergency department and represents heterogeneous causes and diagnoses. There is often a decision to be made regarding emergency
surgical care. Machine learning (ML) could be used here as a decision-support and relieve the time and personnel resource shortage.

Patients with acute abdominal pain presenting to the Department of Surgery at Bonn University Hospital in 2020 and 2021 were retrospectively analyzed. Clinical parameters as well as
laboratory values were used as predictors. After randomly splitting into a training and test data set (ratio 80 to 20), three ML algorithms were comparatively trained and validated. The
entire procedure was repeated 20 times.

A total of 1357 patients were identified and included in the analysis, with one in five (n = 276, 20.3%) requiring emergency abdominal surgery within 24 hours. Patients operated on were
more likely to be male (p = 0.026), older (p = 0.006), had more gastrointestinal symptoms (nausea: p < 0.001, vomiting p < 0.001) as well as a more recent onset of pain
(p < 0.001). Tenderness (p < 0.001) and guarding (p < 0.001) were more common in surgically treated patients and blood analyses showed increased inflammation levels (white blood
cell count: p < 0.001, CRP: p < 0.001) and onset of organ dysfunction (creatinine: p < 0.014, quick p < 0.001). Of the three trained algorithms, the tree-based methods (h2o
random forest and cforest) showed the best performance. The algorithms classified patients, i.e., predicted surgery, with a median AUC ROC of 0.81 and 0.79 and AUC PRC of 0.56 in test
sets.

A proof-of-concept was achieved with the development of an ML model for predicting timely surgical therapy for acute abdomen. The ML algorithm can be a valuable tool in decision-making.
Especially in the context of heavily used medical resources, the algorithm can help to use these scarce resources more effectively. Technological progress, especially regarding artificial
intelligence, increasingly enables evidence-based approaches in surgery but requires a strictly interdisciplinary approach. In the future, the use and handling of ML should be integrated
into surgical training.
Synthesis and Immunological Evaluation of Escherichia coli O1-
Derived Oligosaccharide–Protein Conjugates toward Avian Pathogenic Escherichia coli O1 Vaccine Development
Authors: Toshima Kazunobu , Takahashi Daisuke , Seki Katsunori , Makikawa Takumi
Published: August 2023

Avian pathogenic Escherichia coli O1 (APEC O1) is a pathogenic bacterium that causes significant economic losses in the poultry industry and raises concerns about zoonotic infections. The development of effective vaccines against APEC O1 is essential due to antibiotic resistance and the potential for severe symptoms in both chickens and humans. In this context, we have been focusing on the O1A, O1B, and O1C antigen structures derived from E. coli O1 lipopolysaccharide (LPS). In this study, the first synthesis of the pentasaccharide repeating units of the O1B and O1C antigens was successfully achieved. The synthesis and immunological evaluation of their conjugates with bovine serum albumin (BSA) were conducted. Only the O1A-pentasaccharide structure is a glycotope candidate for APEC O1. Keyhole limpet hemocyanin (KLH)–O1A-pentasaccharide conjugate was also synthesized, and its immunogenicity was evaluated by the ELISA assay. The efficient production of antibodies capable of binding to both APEC O1 LPS and the O1A-pentasaccharide structure was observed, indicating that O1A-pentasaccharide is a promising vaccine candidate against APEC O1.
Prins Cyclization: Novel Strategy towards the Diastereoselective Total Synthesis of (–)-Cryptocaryolone
Authors: Yadav Jhillu Singh , Reddy Basi V. Subba , Biradar Dhanraj O. , Mane Yogesh D.
Published: August 2023

A highly diastereoselective total synthesis of TBDPS-protected (–)-cryptocaryolone has been achieved in 12 linear steps with an overall yield of 7.1%, following a recently developed Prins cyclization strategy for the construction of trans-2,6-disubstituted 3,4-dihydropyrans. Another key intermediate, i.e. syn-1,3-diol, was prepared by the Wacker oxidation followed by a hydroxyl-directed syn-reduction of the keto functionality. In this report, the versatility of Prins cyclization in the total synthesis of TBDPS-protected (–)-cryptocaryolone is demonstrated. The key steps involved in the approach are Prins cyclization for the construction of the trans-2,6-disubstituted dihydropyran, Wacker oxidation and a hydroxyl-directed syn-reduction reaction.
Local Methotrexate Plus Uterine Artery Embolization for High-Risk Interstitial Ectopic Pregnancy
Authors: Mikhitarian Mark , Goodnight III William , Keefe Nicole
Published: August 2023

Interstitial ectopic pregnancy involves the interstitial portion of the fallopian tube and is among the most hazardous of all ectopic pregnancies, with the highest risk of uterine rupture and maternal mortality. Unlike tubal ectopic pregnancy, management of interstitial pregnancy is not well standardized. Systemic methotrexate (MTX) and surgical resection are the primary treatment options; however, failure rates and risk of bleeding remain high. Alternative minimally invasive techniques have been described—including uterine artery embolization (UAE) and local injection of MTX or potassium chloride—and may confer improved success rates. We report a case of a high-risk 28-year-old female with an interstitial ectopic pregnancy successfully treated with combined local injection of MTX plus UAE. We describe our technique and the unique medical management in the setting of a known bleeding disorder.
Placenta Accreta Spectrum: The Role of Interventional Radiology in Multidisciplinary Management
Authors: Sanders Troy K. , Stewart Jessica K.
Published: August 2023

Placenta accreta spectrum is increasing in prevalence and poses significant risks to obstetric patients. This article defines characteristics, diagnosis, management, and outcomes of placenta accreta spectrum, highlighting interventional radiology's role in its management as part of a multidisciplinary approach.
Antiplatelet Therapy in Neurointervention
Authors: Ma Alice , Detaram Harshil Dharamdasani , Steinfort Brendan , Harrington Tim , Nguyen Thanh N. , Abdalkader Mohamad , Siopis George , Bath Philip M. , Dhillon Permesh Singh , Podlasek Anna , Qureshi Adnan I. , Qiu Zhongming , Krishnan Kailash
Published: August 2023

The aim of this review is to provide an overview of the use of antiplatelet medication in neurointervention, with a focus on the clinical indications for antiplatelet use in both preventing and reducing platelet aggregation. This review will cover current antiplatelet medications, pharmacokinetics, and pharmacodynamics. We will provide an overview of different endovascular devices and discuss the antiplatelet regimes in neurointervention, highlighting gaps in evidence and scope for future studies.

Two randomized controlled trials have evaluated antiplatelet use in the setting of acute large vessel occlusion stroke, with neither demonstrating benefit in their overall cohorts. Evidence on antiplatelet medication for both acute and elective stenting for acute stroke and treatment of cerebral aneurysms is currently based on large case series, and practice in neurointervention has increasingly utilized dual antiplatelet regimes with clopidogrel and second-line agents like prasugrel and ticagrelor. Clopidogrel function testing has an increasing role in neurointerventional procedures, particularly for high metal surface area stents such as the braided flow diverter type stents. Intravenous glycoprotein IIB/IIIA inhibitors have been utilized for both acute bridging and rescue therapy.

Antiplatelet decision making is complex, and there are few randomized control trials to guide clinical practice. Comparative trials to guide decision making remain important in both the acute and elective settings. Standardised protocols incorporating platelet function testing may play a role in assisting decision making until more robust clinical evidence is available, particularly in the context of acute neurointerventional stenting for stroke and ruptured cerebral aneurysms.