bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Tramline Sign in the Prediction of Placenta Accreta Spectrum and Perioperative Outcomes in Anterior Placenta Previa
Authors: Dall’Asta Andrea , Forlani Francesco , Shah Harsha , Paramasivam Gowrishankar , Yazbek Joseph , Bourne Tom , Calì Giuseppe , Lees Christoph
Published: February 2021

Purpose To evaluate perioperative outcomes and the prognostic role of the tramline sign in a cohort of women with anterior placenta previa.

Materials and Methods Retrospective analysis of 3D ultrasound volumes from women with anterior placenta previa who underwent ultrasound examination beyond 32 weeks. 3D and 3D color volumes were obtained from a sagittal section of the uterus bisecting a partially full bladder and processed using Crystal Vue and Crystal Vue Flow rendering to look for the “tramline sign”. “Partial obliteration” was defined as a loss of some or part of the uterine-serosal interface and “full obliteration” as when both interfaces were interrupted. Postnatal ascertainment of placenta accreta spectrum (PAS) was confirmed by findings recorded intraoperatively or on a pathology report.

Results 65 cases were included. The tramline sign was “partially” (17) or “fully” (19) obliterated in 36 cases (55.4 %), and present in 29 (44.6 %). Obliteration was associated with earlier gestational age at delivery (35 + 1 (26 + 3–38 + 3) vs. 36 + 4 (25 + 3–38 + 0) weeks, p = 0.005), greater estimated blood loss (800 (400–11 000) vs. 600 (300–2100) mls, p = 0.003), longer operative time (155 (60–240) vs. 54 (25–80) minutes, p < 0.001), higher rate of hysterectomy (97.2 % vs. 0.0 %, p < 0.001), longer postoperative admission (7 (3–19) vs. 3 (1–5) days, p < 0.001) and a 100 % rate of postnatal diagnosis of PAS. The finding of an “obliterated” tramline sign identified all women that required hysterectomy and all cases of PAS.

Conclusion A “partially or fully obliterated” tramline sign is strongly associated with indicators of operative complexity, the postnatal confirmation of PAS, and the need for peripartum hysterectomy.
Heiminfusionstherapie bei Morbus Pompe: Konsensusempfehlungen für den
deutschsprachigen Raum
Authors: Hahn Andreas , Lampe Christina , Boentert Matthias , Hundsberger Thomas , Löscher Wolfgang , Wenninger Stephan , Ziegler Andreas , Lagler Florian , Ballhausen Diana , Schlegel Thomas , Schoser Benedikt
Published: February 2021

Hintergrund Der Morbus Pompe ist eine lysosomale Multisystemerkrankung mit
prädominanter Myopathie, für die eine Enzymersatztherapie (EET) mit rekombinanter
α-Glucosidase verfügbar ist. Diese muss aktuell zweiwöchentlich lebenslang erfolgen. Um
die Belastung durch diese Behandlungsform gering zu halten, besteht bei vielen Betroffenen
der Wunsch, die EET zu Hause als sog. Heiminfusionstherapie durchzuführen.

Ziele und Methoden Im Rahmen zweier Deutsch-Österreichisch-Schweizerischer
Konsensus-Expertentreffen in den Jahren 2019 und 2020 wurde diskutiert, welche
Voraussetzungen gegeben sein müssen, damit eine Heiminfusionstherapie medizinisch
vertretbar erfolgen kann, wie diese sachgemäß durchzuführen ist und wie die Rechtslage für
delegierende Ärzte aussieht.

Ergebnisse und Diskussion Prinzipiell ist bei Patienten mit Morbus Pompe eine
Heiminfusionstherapie möglich, wenn bestimmte Voraussetzungen erfüllt sind. Die
Entscheidung muss für jeden Patienten individuell getroffen werden. Der behandelnde Arzt
delegiert die Durchführung der Heiminfusionstherapie ad personam an eine
Pflegekraft. Die Endverantwortung für die korrekte Durchführung der EET verbleibt aber
beim Arzt. Die Heiminfusionstherapie muss durch speziell geschultes Pflegepersonal
erfolgen. Hauptrisiko ist das Auftreten allergischer Reaktionen. Deren adäquate
Erstbehandlung muss ebenso sichergestellt sein wie die Verfügbarkeit einer
notfallmedizinischen Versorgung. Um die psychosoziale Belastung von Patienten mit Morbus
Pompe in deutschsprachigen Ländern zu minimieren und delegierenden Ärzten größere
Rechtssicherheit zu geben, sind klarere Regelungen für die Durchführung einer
Heiminfusionstherapie wünschenswert.
Access to Highly Substituted Pyrimidine N-Oxides and 4-Acetoxymethyl-Substituted Pyrimidines via the LANCA Three-Component Reaction–Cyclocondensation Sequence
Authors: Zimmer Reinhold , Reissig Hans-Ulrich , Schefzig Luise , Kurzawa Timon , Rancan Giaime , Linder Igor , Leisering Stefan , Bera Mrinal K. , Gart Max
Published: February 2021

The LANCA three-component reaction of lithiated alkoxy­allenes (LA), nitriles (N), and carboxylic acids (CA) smoothly provides β-alkoxy-β-ketoenamides in broad structural variety. The subsequent cyclocondensation of these compounds with hydroxylamine hydrochloride afforded a large library of pyrimidine N-oxides under mild conditions and in good yields. Their synthetic utility was further increased by the Boekelheide rearrangement leading to 4-acetoxymethyl-substituted pyrimidines. With trifluoroacetic anhydride the rearrangement proceeds even at room temperature and directly furnishes 4-hydroxymethyl-substituted pyrimidine derivatives. The key reactions are very robust and work well even in the presence of sterically demanding substituents.
Reconstruction of a Severely Damaged Cartilaginous Septum with a Bypass L-Strut Graft using Costal Cartilage
Authors: Choi Woo Ri , Jang Yong Ju
Published: February 2021

Objective Reconstruction of a weakened septal cartilage is a key procedure for the correction of deformed noses. However, when septal mucoperichondrium dissection is technically challenging, reconstruction of the lower two-thirds of the nose should be performed bypassing the damaged septal cartilage and mucosa. This article summarizes our experience with treating patients with severely damaged septal cartilage with bypass L-strut graft using costal cartilage.

Methods We retrospectively reviewed 26 patients who underwent rhinoplasty using bypass L-strut graft. Autologous costal cartilage was used for creating L-strut in two different ways: (1) by fashioning the L-shaped graft as one unit using the sixth rib cartilage and (2) by integrating a dorsal strut with a columellar strut using slices of the seventh rib cartilage. The caudal strut is fixated to the anterior nasal spine; the dorsal L-strut is placed on the nasal dorsum with no fixation to the nasal bone. Medical records were assessed for demographic, clinical, and treatment information.

Results One-piece-type L-strut graft was used for 11 patients and integrated-type L-strut graft was used for 15 patients. No statistical differences were found in postoperative aesthetic outcomes between the two groups. The postoperative assessment of surgical outcomes was excellent in 10 patients, good in 10, fair in 6, and poor in none. Functionally, all 26 patients experienced improvements in nasal breathing.

Conclusion Bypass L-strut graft using costal cartilage is a useful surgical maneuver of septal reconstruction in particular nasal deformity when the creation of the septal mucoperichondrial pocket is difficult or better to be avoided.
Kma Entscheider Blog: Die drei zentralen Erfolgsfaktoren für Kliniken 2021
Authors: Heurich Manuel
Published: February 2021

In diesem Jahr stehen viele Stakeholder des Gesundheitswesens und insbesondere der Krankenhäuser vor einem Scheideweg zwischen Erfolg und Misserfolg. Die Kernthemen und wichtigsten Voraussetzungen für ein erfolgreiches Jahr 2021 erörtere ich in diesem Artikel.
Thieme Management Award 2020: Feierliche Ehrung trotz Corona
Authors: Orth Anne
Published: February 2021

Auch zum Jahresbeginn 2021 haben kma Klinik Management aktuell und der Club der Gesundheitswirtschaft den Thieme Management Award verliehen – erstmals in einer virtuellen Gala.
Impfbereitschaft: Ringen um einen kleinen Piks
Authors: Doelfs Guntram , Kohrs Jens
Published: February 2021

Wie steht es um die Impfbereitschaft des medizinischen Personals? Was können Kliniken tun, wenn sich nicht genügend Beschäftigte impfen lassen? Der vermeintliche Ausweg aus der Pandemie ist bislang vor allem eines – Grund für Diskussionen und immer neue Fragen.
Strategische Patientenverlegung: Vertrauen aufs Kleeblatt
Authors: Kohrs Jens
Published: February 2021

Überlastete Intensivstationen sind der Albtraum der Klinikchefs. Um Häuser in stark von der Pandemie betroffenen Regionen zu helfen, können Patienten bundesweit verlegt werden. Dafür gibt es das neue Kleeblattkonzept. Nach den ersten Erfahrungen sehen sich die Planer bestätigt.
Computertomographie: Diagnostik im Container
Authors: Lang Michael
Published: February 2021

Container-basierte Computertomographen ermöglichen in der Pandemie, eine Patientengruppe räumlich isoliert von anderen Patienten und Krankenhausmitarbeitern zu untersuchen.
Exoskelett Für Neurochirurgen: Mehr Präzision bei langen OPs
Authors: Kucera Martin
Published: February 2021

Die negativen Folgen von Haltungsschäden für Chirurgen während langer OPs sind vielfältig. Seit Frühjahr 2020 testen Neurochirurgen der Uniklinik Tübingen und der Universitätsmedizin Göttingen ein spezielles Exoskelett, um sie zu vermeiden. Die Erfahrungen sind vielversprechend.
A Behavioral Intervention Increases Consumption of a New Biofortified Food by School Children: Evidence from a Field Experiment in Nigeria
Authors: Just David R. , Okello Julius J. , Gabrielyan Gnel , Adekambi Souleimane , Kwikiriza Norman , Abidin Putri E. , Carey Edward
Published: February 2021

Children’s diets can have major implications for a wide range of diseases and their development outcomes. In Africa, micronutrient deficiency remains a major challenge and affects the health and development of vulnerable populations, especially children. A major effort to combat micronutrient deficiency has targeted biofortification of staple foods, with greatest potential being registered in the enrichment of, among others, sweetpotato with beta carotene—a precursor for vitamin A. However, overcoming vitamin A deficiency is made all the more complicated by children’s general resistance to unfamiliar foods. We report the results of a field experiment in Nigerian schools designed to use behavioral techniques to promote consumption of an unfamiliar food: the pro-vitamin A rich orange-fleshed sweetpotato. We find that children eat more, on average, when the sweetpotato is introduced alongside behavioral nudges such as songs or association with aspirational figures. These results appear to conform to results found in a developed country context.
Experiencing and supporting institutional regionalization in Belgium: a normative and interpretive policy feedback perspective
Authors: Verhaegen Soetkin , Dupuy Claire , Van Ingelgom Virginie
Published: February 2021

Regionalization has been a defining feature of European politics since the 1970s. Previous work has studied political drivers of the movements of competences to the subnational level, including the role of citizens’ preferences. Yet, we still know little about how these new divisions of competences between government levels have impacted the development of public opinion about this division. The article builds on the literature on policy feedback and argues that institutional regionalization may both directly and indirectly affect support for regionalization through normative and interpretive effects. To empirically qualify these expectations, the article uses eight cross sections of the Flemish and Walloon populations in Belgium (1991–2019). This approach explains differences in support for regionalization between citizens that were socialized in different institutional and regional contexts. The analyses show that Walloons who came of age in the context of more institutional regionalization tend to be more supportive of regionalization. In Flanders, in contrast, support for regionalization is most consistently and substantially explained by regional and Belgian identification. However, our analyses show no support for the expectation that coming of age in a more regionalized Belgium is associated with a greater sense of regional identification.
Multiscale adaptive multifractal analysis and its applications
Authors: Han Guo-Sheng , Zhou Fang-Xin , Jiang Huan-Wen
Published: February 2021

To precisely analyze the fractal nature of a short-term time series under the multiscale framework, this study introduces multiscale adaptive multifractal analysis (MAMFA) combining the adaptive fractal analysis method with the multiscale multifractal analysis (MMA). MAMFA and MMA are both applied to the two kinds of simulation sequences, and the results show that the MAMFA method achieves better performances than MMA. MAMFA is also applied to the Chinese and American stock indexes and the R-R interval of heart rate data. It is found that the multifractal characteristics of stock sequences are related to the selection of the scale range s. There is a big difference in the Hurst surface's shape of Chinese and American stock indexes and Chinese stock indexes have more obvious multifractal characteristics. For the R-R interval sequence, we find that the subjects with abnormal heart rate have significant shape changes in three areas of Hurst surface compared with healthy subjects, thereby patients can be effectively distinguished from healthy subjects.
Magnetohydrodynamics model of an X-class flare in NOAA active region 12017 initiated with non-force-free extrapolation
Authors: Nayak Sushree S. , Bhattacharyya R. , Kumar Sanjay
Published: February 2021

We present a three-dimensional magnetohydrodynamic simulation of the NOAA active region 12017 to explore the onset of an X-class flare on 2014 March 29 at 17:48 UT. The simulation is initiated with a magnetic field constructed by non-force-free-field extrapolation of the photospheric magnetic field. Importantly, the initial field contains a three-dimensional magnetic null, a pair of magnetic flux ropes, and a set of sheared arcades overlying the flux ropes at the flare location. A set of magnetic field lines are also identified which connect the flaring location to a distant region affected by the flare. The simulated evolution documents the magnetic reconnections at the null, which can potentially explain the observed chromospheric brightenings during the flare. The sheared arcades also appear to rise and participate in reconnections at the null. Notably, under the favorable initial Lorentz force, the flux ropes lose their twist due to reconnection. The terminal geometry of the ropes and the arcades are similar to the observed post-flare loops. Interestingly, the connecting field lines appear to take part in reconnections at the null, which may lead to the brightenings at the distant region. Further, the free energy released during the evolution which turns out to be ≈6.8×1031 ergs matches well with the observation.
Precipitation of dopants on acceptor-doped LaMnO3±δ revealed by defect chemistry from first principles
Authors: Hess Franziska , Yildiz Bilge
Published: February 2021

Perovskite oxides degrade at elevated temperatures while precipitating dopant-rich particles on the surface. A knowledge-based improvement of surface stability requires a fundamental and quantitative understanding of the dopant precipitation mechanism on these materials. We propose that dopant precipitation is a consequence of the variation of dopant solubility between calcination and operating conditions in solid oxide fuel cells (SOFCs) and electrolyzer cells (SOECs). To study dopant precipitation, we use 20% (D = Ca, Sr, Ba)-doped LaMnO3+δ (LDM20) as a model system. We employ a defect model taking input from density functional theory calculations. The defect model considers the equilibration of LDM20 with a reservoir consisting of dopant oxide (DO), peroxide (DO2), and O2 in the gas phase. The equilibrated non-stoichiometry of the A-site and B-site as a function of temperature, T, and oxygen partial pressure, p(O2), reveals three regimes for LDM20: A-site deficient (oxidizing conditions), A-site rich (atmospheric conditions), and near-stoichiometric (reducing conditions). Assuming an initial A/B non-stoichiometry, we compute the dopant precipitation boundaries in a p–T phase diagram. Our model predicts precipitation both under reducing (DO) and under highly oxidizing conditions (DO2). We found precipitation under anodic, SOEC conditions to be promoted by large dopant size, while under cathodic, SOFC conditions precipitation is promoted by initial A-site excess. The main driving forces for precipitation are oxygen uptake by the condensed phase under oxidizing conditions and oxygen release assisted by B-site vacancies under reducing conditions. Possible strategies for mitigating dopant precipitation under in electrolytic and fuel cell conditions are discussed.
Digital communication using a cyclic level scheme in an atomic radio-over-fiber device
Authors: Pradosh K. N. , Adwaith K. V. , Meena M. S. , Narayanan Andal
Published: February 2021

We experimentally demonstrate binary phase-shift keying and multi-stage four phase shift keying of a microwave carrier and its corresponding demodulation in the optical regime using room temperature Rb atoms. We use a cyclic three-level scheme in 85Rb atoms to achieve this. The importance of our scheme is that the cyclic, closed interaction of the atomic levels with electromagnetic fields makes our system inherently sensitive to the phase of the microwave field. This enables our system to directly encode a phase modulated digital signal in the microwave field and decode it as intensity modulation in the optical field. We measure the correlation of our demodulated optical signal with an ideal template and establish a viable signal bandwidth of about 1 MHz. Our atomic scheme also enables phase dependent amplification of the demodulated optical signal through a hybrid second order nonlinearity. This phase dependent atomic antenna has inherent features of demodulation, radio-to-optical conversion, and amplification. The ground states used in our scheme are quantum memory storage spin states, which makes our scheme inherently suitable for applications involving communication and storage and retrieval of quantum signals.
A comprehensive model and numerical analysis of electron mobility in GaN-based high electron mobility transistors
Authors: Berdalovic I. , Poljak M. , Suligoj T.
Published: February 2021

GaN-based heterostructures have been used in high-power radio frequency applications for a number of years due to the wide bandgap of GaN and high values of spontaneous and piezoelectric polarization, resulting in high breakdown voltages and high 2D carrier concentrations. However, the accurate modeling of low-field electron mobility within such structures remains a topic of interest. This paper presents a comprehensive numerical model for calculating the carrier mobility within a 2D electron gas in AlxGa1−xN/GaN high electron mobility transistors. The model is based on solving the Schrödinger and Poisson equations self-consistently, taking into account the polarization charges at material interfaces and performing semi-classical numerical calculations of low-field electron mobility within the momentum relaxation time approximation, taking into account all relevant scattering mechanisms. Both intra- and inter-subband transitions are considered, and the differences in intra- and inter-subband scattering rates are analyzed for some of the key scattering mechanisms. The importance of including inter-subband transitions in the calculations is demonstrated by comparing the calculated results with experimentally measured mobilities.
Crack-free femtosecond laser processing of lithium niobate benefited by high substrate temperature
Authors: Li Zhixuan , Wu Qiang , Hu Xiaoyang , Jiang Xinda , Zhang Jianmin , Pan Chongpei , Yao Jianghong , Xu Jingjun
Published: February 2021

Femtosecond lasers (fs-lasers) offer a powerful and advantageous tool for fabricating a very large variety of materials. When processing transparent dielectrics, structural defects, such as cracks and broken edges, are always present, thus restricting the precision of fs-laser processing. In this paper, the formation and suppression mechanism of fs-laser induced structural defects are systematically studied. We demonstrate a novel method to improve the processing precision of lithium niobate (LiNbO3) by elevating the substrate temperature. A crack-free ablation hole with a smooth edge was fabricated at the substrate temperature of 1000 °C. Our results show that the increase of absorptivity and the suppression of incubation effects are responsible for the high precision processing at a high substrate temperature, which not only inhibits the formation of defects, but also additionally increases the efficiency of fs-laser processing. This work provides a simple method to efficiently suppress the defect formation induced by fs-laser in LiNbO3 samples, paving the way for a new technique for high precision fs-laser processing.
Hematite reconstruction of Late Triassic hydroclimate over the Colorado Plateau
Authors: Lepre Christopher J. , Olsen Paul E.
Published: February 2021

Significance

Hematite provides much of the color for the classic Triassic–Jurassic “red beds” of North America and elsewhere. Measuring the spectrum of visible light reflected and absorbed by the red beds, we demonstrate that the hematite concentrations faithfully track 14.5 million years of Late Triassic monsoonal rainfall over the Colorado Plateau of Arizona and use this information to assess interrelationships between environmental perturbations, climate, and the evolution of terrestrial vertebrates. The research challenges conventional ideas that the hematite has limited use for interpreting the ancient past because it is a product of natural chemical alterations that occurred long after the beds were initially deposited.
The Krüppel-like factor Cabut has cell cycle regulatory properties similar to E2F1
Authors: Zhang Peng , Katzaroff Alexia J. , Buttitta Laura A. , Ma Yiqin , Jiang Huaqi , Nickerson Derek W. , Øvrebø Jan Inge , Edgar Bruce A.
Published: February 2021

Significance

We discovered that the
Drosophila
transcription factor, Cabut, an ortholog of human KLF-10 and KLF-11, is capable of
trans
-activating a large set of cell cycle genes that are also E2F1 targets. Thereby, Cabut can drive ectopic cell cycles in many
Drosophila
cell types. That Cabut has E2F-like activity is especially interesting when one considers that the E2Fs, which are the best characterized transcriptional regulators of the eukaryotic cell cycle, are not actually essential for cell cycle gene transcription or cell cycle progression. Hence, it is clear that other transcription factors must also regulate the transcription of the 300 to 400 genes necessary for DNA replication and mitosis. Cabut appears to be one these missing transcription factors that can complement E2F.
A new role for joint mobility in reconstructing vertebrate locomotor evolution
Authors: Manafzadeh Armita R. , Kambic Robert E. , Gatesy Stephen M.
Published: February 2021

Reconstructions of movement in extinct animals are critical to our understanding of major transformations in vertebrate locomotor evolution. Estimates of joint range of motion (ROM) have long been used to exclude anatomically impossible joint poses from hypothesized gait cycles. Here we demonstrate how comparative ROM data can be harnessed in a different way to better constrain locomotor reconstructions. As a case study, we measured nearly 600,000 poses from the hindlimb joints of the Helmeted Guineafowl and American alligator, which represent an extant phylogenetic bracket for the archosaurian ancestor and its pseudosuchian (crocodilian line) and ornithodiran (bird line) descendants. We then used joint mobility mapping to search for a consistent relationship between full potential joint mobility and the subset of joint poses used during locomotion. We found that walking and running poses are predictably located within full mobility, revealing additional constraints for reconstructions of extinct archosaurs. The inferential framework that we develop here can be expanded to identify ROM-based constraints for other animals and, in turn, will help to unravel the history of vertebrate locomotor evolution.
The measurement of deformation of elastic shapers of various stiffness and assessment of the influence of shaper deformation on the parameters of the shock pulse
Authors: Shtreker D S , Popov A N , Reshetov D V , Utkin G A
Published: February 2021

In this paper the influence of the deformation of the shapers of various stiffness on the vibration characteristics of the impact is estimated. In particular, the influence of the deformation on the high-frequency vibrations that appears during the operation of the shapers is also estimated. Both analytical and experimental results of measuring of deformation of shapers are presented. The structure of the model of the shock testing machine developed in Peter the Great St. Petersburg Polytechnic University is described in details. An algorithm for the analysis of vibration characteristics obtained during the tests on the model of an impact machine is presented. The results of studies of the characteristics of the materials which the shock pulse shapers are made of are presented. The life of the shapers made of various materials is estimated. Analytic and experimental dependences of the shaper deformation on the lifting height of the shock table are presented. Conclusions about the effect of shaper deformation on impact parameters are drawn.
Investigation of the suitable dimensions for hydraulic prop support of self-advancing hydraulic roof support in underground mining at Quang Ninh coal basin in Viet Nam
Authors: Lykov Yu V , Nhu Bui Thanh , Trong Do Duc , Tung Le Van
Published: February 2021

According to the study, the authors have calculated and determined the reasonable size of hydraulic prop support of self-advancing hydraulic roof support, used in underground coal mining in the Quang Ninh area. The study took into account various factors that are related to the geological conditions of the mine areas, the manufacturing materials, and mining technology. The results obtained from the study can be reasonably applied to calculate the suitable size of the hydraulic prop support based on the durability and stability required for coal mines with similar geological conditions as the Quang Ninh mines. The study was carried out with the aim of improving the efficiency of using hydraulic prop support and reducing product costs. In addition, the research results can be the basis for calculating other types of hydraulic prop support used as a reference for manufacturing other underground coal mining supports at Quang Ninh coal basin.
Method of development of snow mobility maps
Authors: Zhukov S S , Makarov V S , Belyakov V V
Published: February 2021

The article discusses the need to create mobility maps as the next stage of the development of the mobility theory of Professor Belyakov. The analysis is based on data showing that the development of “snow mobility maps” is relevant for Russia. The main stages of the methodology for constructing “snow mobility maps” are given, which include: analysis of the terrain in order to determine the characteristic zones of movement, determining the parameters of moving objects and calculation of the parameters of vehicles mobility with reference to graphic information systems.
Increasing the breaking capacity of the 10 kV VAC in comparison with its own axial and radial magnetic fields
Authors: Cherenkov V A , Ivanov D V , Frolov V Y , Malavanh Onepavina
Published: February 2021

The research work considers vacuum arc-extinguishing chambers with axial and radial magnetic fields. The object of research is vacuum arc suppression chambers with an axial magnetic field of 10 kV, 20 kA and with a radial magnetic field of 10 kV, 40 kA as well as ways to increase the breaking capacity by changing the configuration for each type of chambers. The research work uses the method of mathematical modeling of physical processes in the Comsol Multiphysics software package, graphical modeling of chambers is performed in Compass v18. 0. The results showed that changing the geometric parameters of vacuum arc-extinguishing chambers can increase the breaking capacity. Based on the results obtained, it can be concluded that to increase the maximum cut-off current, it is sufficient to change the geometry of the vacuum arc-extinguishing chamber. In combination with other ways to increase the breaking capacity, it is possible to expand the area of application of vacuum interrupters - the most reliable, safe and environmentally friendly switching devices.
Electrotechnical complex for autonomous power supply of oil leakage detection systems and stop valves drive control systems for pipelines in arctic region
Authors: Belsky A A , Dobush V S , Ivanchenko D I , Gluhanich D Y
Published: February 2021

The article is dedicated to the important task of detection and elimination of liquid hydrocarbon leak in oil pipelines. The technological, regulatory and geographical aspects of the use of existing oil leakage detection systems (LDSs) and pipeline stop valves drive control systems are considered. The authors have proposed a new solution for autonomous power supply of oil LDS and stop valve drive control systems for pipelines located in inaccessible areas. The proposed autonomous power supply complex is based on thermoelectric generation units. The composition and parametric sufficiency of the autonomous complex is substantiated. The authors have developed the laboratory test bench, which verified the technical characteristics of the complex. The authors have substantiated the possibility of various designs for application of such complexes in existing pipelines.
To the question of determining bending stress of a buried pipeline from the ground surface
Authors: Aginey R V , Firstov A A , Kapachinskikh Zh Yu
Published: February 2021

The laying of buried pipelines in difficult engineering and geological conditions is associated with the need to take into account a large number of factors affecting the process of pipeline operation. It is practically impossible to take into account all these factors at the design stage. In this regard, methods that make it possible to assess the technical condition of the pipeline at a specific point in time acquire particular relevance. One of the promising methods for assessing the technical condition of underground pipelines is to survey the depth of the axis of the underground pipeline from the ground surface with subsequent use of the data obtained to assess the level of bending stress. The low popularity of this method lies in the large errors obtained in the calculations according to the developed methods. In the work, the reasons for the occurrence of significant errors in determining bending stresses when using survey data were analyzed, mathematical dependencies were proposed that make it possible to evaluate bending stress based on the data obtained with the accuracy specified at the design stage of the experiment. Calculations are provided that confirm the adequacy of the proposed mathematical models.
Centralizing devices to complement acoustic logging tools
Authors: Gilmanova A M
Published: February 2021

One of the cornerstones to high-precision acoustic logging equipment is high reliability and maneuverability of tools in a sophisticated well. The paper outlines the requirements for centralizing devices (CD), experimental and theoretical rationale for different configurations, and the need for appropriate calculations. The outputs involve a series of updated centralizing devices, the classification of centralizing devices and a crossplot that all allow for an optimal centralizing configuration to be selected depending on the equipment available and a well examined.
Effect Implementation of Information Technology Software On Improving Performance Capacity Academic and Non Academic Service Sunan Ampel Islamic University of Surabaya
Authors: Ilham  , Eliyana Anis , Rizki Sridadi Ahmad , Usman Indrianawati , Purnomo Agung
Published: February 2021

This research was conducted to examine the effect of applying information technology software to increase the capacity of academic and non-academic performance at the Sunan Ampel State Islamic University in Surabaya as a work support tool. The aim is to apply a software that is able to identify the needs of increasing performance capacity at Sunan Ampel State Islamic University in Surabaya, both academic and non-academic, so that systematic control and evaluation of all academic and non-academic operations can be carried out. The research respondents were 60 students and employees from the Faculty of Science and Technology of the Sunan Ampel State Islamic University in Surabaya. This research uses a quantitative approach with the analysis technique used is path analysis with SmartPLS software-based data processing and the overall results support the hypothesis. Based on the results of the study stated that Information Technology has a positive and significant effect on performance, Information Technology has a positive and significant effect on academic services, Information Technology has a positive and significant effect on non-academic services, but performance has no effect on academic and non-academic services. The conclusion of the research is the influence of the application of information technology software can improve academic and non-academic performance and services at the Sunan Ampel State Islamic University of Surabaya
Design of Discovery Learning Model Biodiversity Integrated to Develop the Scientific Attitude of Student
Authors: Mulyani Aty , Rusdi Muhammad , Yelianti Upik , Syahrial
Published: February 2021

In learning Biology with a scientific approach, the scientific attitude becomes important to be developed in students, the problem is not all teachers have the creativity and innovation to develop the scientific attitude. In this study, stages will be carried out to design a scientific approach to discretion for the subject of integrated ethnobotany biodiversity and religious value. The Ethnobotany Study is interesting because this study discusses the biodiversity of local plant species, the names of these plants in local terms, scientific names, benefits for life, as well as including their classification in Plant taxonomies. This type of research is a qualitative descriptive research. In this study, the research team conducted observations, interviews with officers and resource persons at Perhutani Jambi with address: Jln Lintas Jambi-Palembang, Kenali Asam Bawah, Kota Baru, Jambi, KM 11, Jambi. Data obtained related to the type of local plants are carried out verification and data reduction, and integrating local plant knowledge in the context of ethnobotany in the subject of Biodiversity in Biology. The results of the study found five main local plants in tropical forests, namely (1) Jatropha (Ricinus communis). (2) Bulian (Eusideroxylon zwageri), (3) Meranti Bunga (Shorea leprosula Miq), (4) Meranti Putih (Shore spp) (5) Jengkol (Archidendron pauciflorum) (6) Gaharu (Aquilaria malaccensis), (7) Ketapang (Terminalia cattapa) In this study it was also found that local plants as ethnobotany were cultivated mostly for blandar wood (beam), Usuk, and house sills, because they were resistant to termites, namely Bulian, Meranti Bunga, Meranti Putih plants, Gaharu type plants for deodorant can be taken, other types of productive plants found fruit, and ornamental plants for parks or protectors to be planted on the roadside. In its application, the information obtained from these types of plants and their benefits are packaged in the study of Biodiversity in Biological Materials. The design of teaching materials, the teacher assigns assignments to students for observation, interviews, analyzing data, and presenting their findings in the Perhutani Tropical Forest to increase the scientific attitude of students.And assigns assignments to discovers sens of religious value at The Holy Alquran related to religious values on biodiversity material.
Implementation of Google Meet Application in the Learning of Basic Science in the Covid-19 Pandemic Period of Student Learning Interests
Authors: Septantiningtyas Niken , Juhji Juhji , Sutarman Adang , Rahman Abd , Sa’adah Nurus , Nawisa
Published: February 2021

This research is a quantitative study aimed to find the effect of the Google meet application on student interest in the University of Nurul Jadid Paiton Probolinggo by using experimental design research design using two parallel classes, one class is used for experimental treatments and one other class as a control class. There is a significant difference between the experimental class conducted by learning using the Google Meet application and the control class where the learning process is carried out directly (face to face). The highest interval of interest in learning is found in the experimental class with a score of 110 and the lowest with a score of 94 with an average interval of 101.84. While the control class only had the highest score of 106 and the lowest score of 70 with an average interval of 89.52. So with this overall data that learning using the Google meet application has a very high influence on student interest in learning this is because the learner is very easy to implement, time is flexible and can be implemented where each student is located.
Self-Regulation using Moodle Virtual Learning Environment (VLE) in Solar System Practice
Authors: Rosyadi BR , Nisa Khoirun , Afandi Irfan , Rozi Fathor , Fawaid Ahmad , Fajri Zaenol , Hasanah Uswatun , Maimunah  , Sri Helmiati S
Published: February 2021

The purpose of this study is to measure the level of self-regulated students obtained from their academic achievements when learning to use Moodle virtual learning environment (VLE) in the practice of the solar system. This study involved 37 students of grade IX junior high school in Paiton Probolinggo, of which 18 students in the experimental group studied using Moodle Virtual Learning Environment (VLE), and 19 students in the control group who studied with conventional learning. In this study, students’ self-regulated measures were measured using a 4-point Likert scale. The results of this study indicate that the level of self-regulated students who learn to use Moodle virtual learning environment (VLE) is higher than students who study conventionally.
Ethnomathematics in Balinese Traditional Dance: A Study of Angles in Hand Gestures
Authors: Radiusman R , Wardani K S K , Apsari R A , Nurmawanti I , Gunawan G
Published: February 2021

The study was aimed to explore the ethnomathematics in hand gestures of Balinese traditional dances. The scope of ethnomathematics discussed was limited to the geometry object, specifically angles. The object of the study was Pendet Dance, one of the popular traditional dance from Bali which usually perform to welcome the guest in a formal and informal event. The method of the research was a case study in which we deeply analyse the hand gestures in Pendet Dance. The data were gathered from observation of the dance and interview the experts in Balinese Dance. The data were analysed qualitatively using descriptive method. From the analysis, it was found that the hand gestures of the dancers in Pendet Dance is forming three types of angles, i.e. acute angle (0° < a < 90°), right angle (a = 90°) and obtuse angle (90° < a < 180°). The angles can be seen in a number of pattern of the hand gestures such as in ngumbang, agem, ulap-ulap and ngelung movement.
Misconceptions and Errors in Integer Operations: A Study in Preservice Elementary School Teachers (PGSD)
Authors: Rosyidah A N K , Maulyda M A , Jiwandono I S , Oktaviyanti I , Gunawan G
Published: February 2021

This study aimed to describe the types of misconceptions conducted by preservice elementary teachers (PGSD) students in integer operations. Misconceptions are classified into 3 types: 1) Careless Errors (Ca); 2) Concept errors (Co); 3) Careless errors and Concept errors (Ca and Co). The researcher presented 6 problems about of integer operation to 45 students of PGSD (preservice teachers for elementary school) students that were taking elementary mathematics subject. The results showed that 10% of students made Careless errors (Ca) misconceptions in integer addition and subtraction. The highest portion of the students, 53% performed Concept error (Co) in subtracting negative numbers. Another 9% showed Careless and Concept error (Ca and Co) misconception in subtraction of integers of the same sign (negative with negative or positive with positive).
Assessment of an air quality surveillance network through passive pollution measurement with mobile sensors
Authors: Lorenzo-Sáez Edgar , Oliver-Villanueva Jose-Vicente , Lemus-Zúñiga Lenin-Guillermo , Coll-Aliaga Eloina , Castillo Carolina Perpiñá , Lavalle Carlo
Published: February 2021

Today, about 55% of the world population lives in cities and this is foreseen to increase to 68% by 2050. The urban activities of such a large number of people in relatively small spaces can make the air quality levels in cities harmful to human health. For this reason, the European Union (EU) has established a regulatory framework to control and improve air quality levels in cities (Directive 2008/50/EC) by defining a number of fixed stations and other requirements. The aim of this work is to evaluate the air quality reported by the official fixed stations via the installation of a complementary mobile network of air quality based on passive dosimetry of NO2 measurement during the period 2017–2019. In this study, Valencia (Spain) is selected as a representative European city with seven fixed stations and a network of 424 passive dosimetry sensors distributed throughout the city. In addition, an index of impact of pollutant on population is developed to optimize the locations of air quality stations among neighbourhoods across the city based on the levels of pollution measured by mobile sensors and the population directly affected. The results obtained show that 43.7% of mobile sensors in Valencia exceeded the limit value established by the EU Directive as well as by the World Health Organization during the assessment period. This indicates that the air quality levels offered by the fixed stations are neither representative nor reliable for the air quality monitoring of the city. Thus, the fixed stations currently operating do not provide reliable information on the areas of the city where the majority of the population breathes air with the highest level of pollution. Specifically, the results show that 34.6% of citizens live in areas with an average annual value above the limit recommended for the protection of human health.
Quantum particle on dual root lattice in Weyl alcove
Authors: Brus Adam , Hrivnák Jiří , Motlochová Lenka
Published: February 2021

Classes of discrete quantum models that describe a free non-relativistic quantum particle propagating on rescaled and shifted dual root lattices inside closures of Weyl alcoves are constructed. Boundary conditions of the discrete quantum billiard systems on the borders of the Weyl alcoves are controlled by specific combinations of Dirichlet and Neumann walls that result from sign homomorphisms and admissible shifts inherent in generalized dual root lattice Fourier–Weyl transforms. The amplitudes of the particle’s jumps to neighbouring positions are controlled by a complex-valued dual root lattice hopping function with finite support. The solutions of the time-independent Schrödinger equation together with the eigenenergies of the quantum systems are explicitly determined. The matrix Hamiltonians and eigenenergies of the discrete models are exemplified for the rank two cases A
2 and C
2.
Integrability in the multistate Landau-Zener model with time-quadratic commuting operators
Authors: Chernyak Vladimir Y , Sinitsyn Nikolai A
Published: February 2021

All currently known exactly solvable multistate Landau–Zener (MLZ) models are associated with families of operators that commute with the MLZ Hamiltonians and depend on time linearly. There can also be operators that satisfy the integrability conditions with the MLZ Hamiltonians but depend on time quadratically. We show that, among the MLZ systems, such time-quadratic operators are much more common. We demonstrate then that such operators generally lead to constraints on the independent variables that parametrize the scattering matrix. Such constraints lead to asymptotically exact expressions for the transition probabilities in the adiabatic limit of a three-level MLZ model. New more complex fully solvable MLZ systems are also found.
Matrix moments in a real, doubly correlated algebraic generalization of the Wishart model
Authors: Guhr Thomas , Schell Andreas
Published: February 2021

The Wishart model of random covariance or correlation matrices continues to find ever more applications as the wealth of data on complex systems of all types grows. The heavy tails often encountered prompt generalizations of the Wishart model, involving algebraic distributions instead of a Gaussian. The mathematical properties pose new challenges, particularly for the doubly correlated versions. Here we investigate such a doubly correlated algebraic model for real covariance or correlation matrices, which is known as matrix variate t-distribution in the statistics literature. We focus on the matrix moments and explicitly calculate the first and the second one, the computation of the latter is non-trivial. We solve the problem by relating it to the Aomoto integral and by extending the recursive technique to calculate Ingham–Siegel integrals. We compare our results with the Gaussian case.
Experimental studies into the kinetics of the process of vacuum drying of carrot chips
Authors: Ustinova M E , Yashonkov A A
Published: February 2021

The need to develop a technology for the production of a new healthy food product from vegetable raw materials has been substantiated in the paper. The choice of carrots of the cultivar Chantenay royal, Champion, Dordogne for use as the feedstock is justified. The design and principle of operation of the installation for conducting experimental studies are described. Experimental studies and a comparative analysis of their results in the production of carrot chips by drying at atmospheric pressure, vacuum drying at a pressure of 10 kPa and using preliminary pore formation followed by vacuum drying at a pressure of 10 kPa has been carried out. By the method of selection of objects according to their belonging to one of the structural elements (product, pores) by analyzing photographs of slices of chips, the dependence of the surface area of moisture evaporation on drying methods has been determined. It was found that the use of preliminary pore formation between the periods of heating the material and a constant drying rate significantly increased the energy efficiency of the process.