bluuebunny/crossref_metadata_2025 huggingface dataset:
Discourses and practices of attention in video chat
Authors: Cserző Dorottya
Published: May 2021

This paper examines the use of video chat (VC) with a focus on expectations and construction of attention. It is based on micro analyses of recorded VC sessions (gathered between 2013 and 2015) and thematic analysis of 29 semi-structured interviews about VC practices (conducted in 2014 and 2015). Building on multimodal (inter)action analysis (Norris, S. (2004). Analysing multimodal interaction: a methdological framework. Routledge, Norris, S. (2016). Concepts in multimodal discourse analysis with examples from video conferencing. Yearbook of the Poznan Linguistic Meeting 2: 141–165) and key concepts from nexus analysis (Scollon, R. and Scollon, S.W. (2004). Nexus Analysis: Discourse and the emerging internet. Routledge), I examine how focused attention is constructed in VCs and how these practices are shaped by experiences with other forms of communication. I demonstrate that unlike other forms of distance communication, typical VC encounters require a full investment of attention. This can be formulated as an interactional maxim: focus your attention on the VC interaction. I discuss how other activities can be interwoven with a VC and examine the exceptional practice of lapsed VC encounters (previously open connections or always-on video). I argue that participants display an orientation towards the maxim when pursuing other courses of action, and that lapsed encounters operate under a different value system than typical focused VC encounters. Finally, I reason that VC is reserved for close relationships because of the required investment of attention.
Crystal structure of cyclopropane-1,2,3-triyltris(phenylmethanone), C24H18O3
Authors: Zeng Li , Tang Gui-Yun , Wang Yu-Cai , Liu Chun-Yan
Published: May 2021

C24H18O3, monoclinic, P21/n (no. 14), a = 5.376(2) Å, b = 15.787(6) Å, c = 21.103(7) Å, β = 92.356(6)°, V = 1789.5(11) Å3, Z = 4, R

gt
(F) = 0.0569, wR

ref
(F
2) = 0.1166, T = 296 K.
A New Method for the Large-Scale Documentation of Pottery Sherds Through Simultaneous Multiple 3D Model Capture Using Structure from Motion: Phoenician Carinated-Shoulder Amphorae from Tell el-Burak (Lebanon) as a Case Study
Authors: Göttlich Fanet , Schmitt Aaron , Kilian Andrea , Gries Helen , Badreshany Kamal
Published: May 2021

This paper presents a new rapid, low-cost method for the large-scale documentation of pottery sherds through simultaneous multiple 3D model capture using Structure from Motion (SfM). The method has great potential to enhance and replace time-consuming and expensive conventional approaches for pottery documentation, i.e., 2D photographs and drawing on paper with subsequent digitization of the drawings. To showcase the method’s effectiveness and applicability, a case study was developed in the context of an investigation of the Phoenician economy at the Lebanese site of Tell el-Burak, which is based on a large collection of amphora sherds. The same set of sherds were drawn by an experienced draftsperson and then documented through SfM using our new workflow to allow for a direct comparison. The results show that the new technique detailed here is accessible, more cost-effective, and allows for the documentation of ceramic data at a far-greater scale, while producing more consistent and reproducible results. We expect that these factors will enable excavators to greatly increase digital access to their material, which will significantly enhance its utility for subsequent research.
Rational engineering of specialized metabolites in bacteria and fungi
Authors: Kamdem Ramsay Soup Teoua , Ogbole Omonike , Wafo Pascal , Philip F. Uzor , Ali Zulfiqar , Ntie-Kang Fidele , Khan Ikhlas A. , Spiteller Peter
Published: May 2021

Bacteria and fungi have a high potential to produce compounds that display large structural change and diversity, thus displaying an extensive range of biological activities. Secondary metabolism or specialized metabolism is a term for pathways and small molecule products of metabolism that are not mandatory for the subsistence of the organism but improve and control their phenotype. Their interesting biological activities have occasioned their application in the fields of agriculture, food, and pharmaceuticals. Metabolic engineering is a powerful approach to improve access to these treasured molecules or to rationally engineer new ones. A thorough overview of engineering methods in secondary metabolism is presented, both in heterologous and epigenetic modification. Engineering methods to modify the structure of some secondary metabolite classes in their host are also intensively assessed.
Inorganic luminescent pigments
Authors: Pfaff Gerhard
Published: May 2021

Inorganic luminescent pigments (luminescent materials, luminophores, phosphors) as synthetically generated crystalline compositions absorb energy followed by emission of light with lower energy, respectively, longer wavelengths. The light emission occurs often in the visible spectral range. External energy is necessary to enable luminescent materials to generate light. Luminescent pigments are divided into fluorescent and phosphorescent pigments. This classification goes back to different energy transitions. Emission based on allowed optical transitions, with decay times in the order of µs or faster is defined as fluorescence. Emission with longer decay times is called phosphorescence. The occurrence of fluorescence or phosphorescence as well as the decay time depend on structure and composition of a specific luminophore. There are four luminescence mechanisms discussed for inorganic luminescent materials: center luminescence, charge-transfer luminescence, donor–acceptor pair luminescence, and long-afterglow phosphorescence. The emission of luminescent light can have its origin in different excitation mechanisms such as optical excitation (UV radiation or even visible light), high-voltage or low-voltage electroluminescence and excitation with high energy particles (X-rays, γ-rays). Inorganic luminescent pigments are used mainly in fluorescent lamps, cathode-ray tubes, projection television tubes, plasma display panels, light-emitting diodes (LEDs) and for X-ray and γ-ray detection. The pigment particles are dispersed for the applications in specific binder systems. They are applied in form of thin layers and by means of luminophore/solvent suspensions, containing adhesive agents, on a substrate.
Mixed metal oxide pigments
Authors: Pfaff Gerhard
Published: May 2021

Mixed metal oxide (MMO) pigments, also knowns as complex inorganic color pigments (CICPs), are an important class of inorganic pigments. They are representatives of the blue, green, yellow, brown, and black pigments. These pigments are called mixed complex because they contain two or more different metals in the composition. Their main advantages are high opacity, heat stability, useful infrared properties, light- and weather fastness, and chemical resistance. MMOs are solid solutions of metal oxides, which are homogenously distributed in their crystal lattices. They are based on different types of crystal structures, such as rutile, spinel, inverse spinel, hematite, priderite, and pseudobrookite. Other products belonging to the CICPs besides the rutile and spinel type MMOs are pigments based on zirconium silicate (zircon, ZrSiO4). Such compositions belong to the class of ceramic pigments (color stains for glazes).
Special effect pigments
Authors: Pfaff Gerhard
Published: May 2021

Special effect pigments are in the very most cases synthetic pigments, characterized by high luster, brilliance and iridescent colors known from optically thin films. The visual appearance has its origin in reflection and refraction of light at thin single and multiple layers. The pigments are either transparent, semitransparent or light-absorbing platelet-shaped crystals or layer systems. They can consist of single crystals, but also of monolayer or a multilayer structures in which the layers have different refractive indices and light absorption properties. Pigment based on the layer-substrate principle represent the technically most important class of special effect pigments. There are many variation and combination possibilities for the layer and substrate materials used. Special effect pigments based on platelets of natural or synthetic mica, on alumina, silica, or borosilicate flakes are the main representatives of layer-substrate pigments. They are manufactured in most cases by wet chemical processes combined with high-temperature processes. The production of substrate particles includes mechanical processes, but also crystal growth, glass formation, and web coating.
Titanium dioxide pigments
Authors: Pfaff Gerhard
Published: May 2021

Titanium dioxide (TiO2) is by far the most important white pigment. The extraordinary scattering behavior of TiO2 together with the lack of absorption in the visible range and the stability in different application systems is the reason why TiO2 is the most commonly used pigment. Of the three TiO2 modifications, only rutile and anatase play a role for pigment uses, whereas brookite has no technical importance. Two main processes are used for the production of TiO2 pigments, the sulfate process and the chloride process. Many TiO2 pigments are equipped with an additional surface treatment (aftertreatment) to improve weather resistance and lightfastness of the pigment itself and of the pigmented organic matrix. A second aim of the surface treatment is the improvement of the dispersibility of the pigments in the application system.
Transparent pigments
Authors: Pfaff Gerhard
Published: May 2021

Transparent pigments are characterized by very small particles with sizes in the range below 100 nm and large specific surface areas. Most of the technically relevant pigments consist of inorganic compounds. Transparent pigments are classified as nanomaterials. Nanosized primary particles do not or only slightly scatter visible light, which is the reason for their transparency. Pigmentation with these pigments leads to a transparent appearance of the application systems. There are colored and colorless transparent pigments. If colored pigments such as α-FeOOH, α-Fe2O3, and CoAl2O4 are used, the application medium takes on color while remaining transparent. Colorless transparent pigments are nearly invisible in the application system. Only in combination with effect pigments or conventional colored pigments, effects with a special appearance are possible, e.g., frost effects. There are two industrially relevant colorless transparent pigments, TiO2 and ZnO. Both pigments find their main applications as functional powders. They are characterized by strong UV absorption and are therefore applied as UV absorbers. As such, they are used for the protection of organic materials such as plastics and coatings. They are used in addition in a broad diversity of sun screen products where they protect human skin. The manufacture of transparent pigments takes place mostly using wet-chemical or gas-phase reactions.
White pigments
Authors: Pfaff Gerhard
Published: May 2021

White pigments are inorganic pigments, whose optical action is mainly based on non-selective light scattering. White pigments do not show absorption in the range of visible light, but have high scattering power leading to high hiding power in their applications. The greater the difference between the refractive index of the white pigment and that of the surrounding medium, the higher the scattering power.
Fluorescence quenching detection of UO2
2+ in aqueous solution based on an organic molecule probe of 6-chloro-2H-1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide
Authors: Elabd Amira A. , Elhefnawy Olivea A.
Published: May 2021

A new organic molecule probe has been introduced as a “turn-off” fluorescent sensor to detect trace quantities of UO2
2+ in the presence of several transition metals with promising results. The procedure is based on quenching the fluorescence intensity of 6-chloro-2H-1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide (L) in the presence of various UO2
2+ concentrations in methanol. The UO2
2+ and L species interact through electrostatic interaction between negatively charged nitrogen atom of the sulfonamide group of L and positively charged UO2
2+, thus facilitating the non-radiative recombination of UO2
2+ and L through the charge transfer or electron transfer processes and leading to the fluorescence quenching of L. The mechanism of quenching was addressed and proved to be static quenching. The impressive quenching of the fluorescence intensity of L by different concentrations of UO2
2+ has been successfully used as a new sensor to measure UO2
2+ in methanol at λ
ex = 340 nm, λ
em = 380 nm with a linear dynamic range of 0.08–5.0 µM and detection limit and quantification limit of 0.0276 and 0.0837 µM, respectively. The L sensor shows interesting advantages compared to other developed sensors with adequate performance, such as broader linear range and lower detection limit, selectivity, and simplicity, which illustrate its useful practical use.
Inheritance and Stockholding: The Role of Expectations
Authors: Luik Marc-André , Salland Jan
Published: May 2021

This paper uses data from the Health and Retirement Study to investigate the role of inheritances for stockholding. Individual heir fixed-effects estimates show that an inheritance receipt increases subsequent stock market participation. The respective magnitude of this shift is higher for large and fully anticipated receipts, whereas it seems to be largest for fully but larger-than-expected transfers. Generally, our effects are driven by households entering the stock market. Also, a less pre-inheritance liquidity constrained household shows higher post-inheritance stock ownership probability. This suggests, inheritance size as well as receipt and size anticipation are determinants for stockholding. In the context of stock market participation, our results highlight considerable heir and transfer heterogeneity which can have important implications for bequest taxation and economic welfare. By means of the intergenerational transmission of inequality and socio-economic status via the ‘wealth channel’, households not only benefit from transfer receipt but also from later capital gains, due to stock market participation.
Fusion of sequential LiDAR measurements for semantic segmentation of multi-layer grid maps
Authors: Bieder Frank , Wirges Sascha , Richter Sven , Stiller Christoph
Published: May 2021

In this work, we improve the semantic segmentation of multi-layer top-view grid maps in the context of LiDAR-based perception for autonomous vehicles. To achieve this goal, we fuse sequential information from multiple consecutive LiDAR measurements with respect to the driven trajectory of an autonomous vehicle. By doing so, we enrich the multi-layer grid maps which are subsequently used as the input of a neural network. Our approach can be used for LiDAR-only 360 ° surround view semantic scene segmentation while being suitable for real-time critical systems. We evaluate the benefit of fusing sequential information using a dense semantic ground truth and discuss the effect on different classes.
Hormones in experimental autoimmune encephalomyelitis (EAE) animal models
Authors: Ghareghani Majid , Ghanbari Amir , Eid Ali , Shaito Abdullah , Mohamed Wael , Mondello Stefania , Zibara Kazem
Published: May 2021

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) in which activated immune cells attack the CNS and cause inflammation and demyelination. While the etiology of MS is still largely unknown, the interaction between hormones and the immune system plays a role in disease progression, but the mechanisms by which this occurs are incompletely understood. Severalin vitroandin vivoexperimental, but also clinical studies, have addressed the possible role of the endocrine system in susceptibility and severity of autoimmune diseases. Although there are several demyelinating models, experimental autoimmune encephalomyelitis (EAE) is the oldest and most commonly used model for MS in laboratory animals which enables researchers to translate their findings from EAE into human. Evidences imply that there is great heterogeneity in the susceptibility to the induction, the method of induction, and the response to various immunological or pharmacological interventions, which led to conflicting results on the role of specific hormones in the EAE model. In this review, we address the role of endocrine system in EAE model to provide a comprehensive view and a better understanding of the interactions between the endocrine and the immune systems in various models of EAE, to open up a ground for further detailed studies in this field by considering and comparing the results and models used in previous studies.
Auf dem Weg zum austeritätspolitischen Föderalismus in Bayern? Eine historisch-materialistische Politikanalyse sparpolitischer Restrukturierungsprozesse in der Raumordnung.
Authors: Dudek Simon
Published: May 2021

Die als Erfolgsmodell geltende bayerische Raumplanung wurde in den letzten Jahren kontinuierlich geschwächt. Mit der materialistischen Staatstheorie lässt sich dieser Wandel als Folge austeritärer Staatlichkeit fassen. Vor diesem Hintergrund ergründet der Beitrag die Konsequenzen dieser Verschiebung für die Raumordnung. Anhand feststellbarer Prozesse der Kommunalisierung, Verwettbewerblichung und Responsibilisierung lässt sich die Herausbildung eines austeritätspolitischen Föderalismus feststellen.
Die doppelte Fetischisierung der Staatsschulden
Authors: Belina Bernd
Published: May 2021

Staatsschulden werden in diesem Beitrag auf ihre doppelte Fetischisierung hin untersucht. Sie erscheinen, obschon Resultat komplexer gesellschaftlicher Prozesse, als Ding, das mit simplen moralischen Urteilen aufgeladen werden kann. Unter Rückgriff auf die Fetischtheorie von Karl Marx und die darauf aufbauende Verdinglichungstheorie von Georg Lukács wird argumentiert, dass diese Verdinglichungen in den grundlegenden Strukturen des Kapitalismus angelegt sind, den sozialen Formen; und dass sie durch theoretische Kritik und politische Praxis verflüssigt werden können. Dabei wird unter Bezugnahme auf weitere Positionen des Westlichen Marxismus mit Lukács über Lukács hinausgegangen, indem die spezifischen Fetischisierungen des Schuldenfetischs und des Territorialfetischs bestimmt werden und ihre Kombination zur Erklärung der extremen Verdinglichung der Staatsschulden herangezogen wird. Insgesamt plädiert der Beitrag für eine an die Dialektik von Verdinglichung und Verflüssigung orientierte Untersuchung und Kritik geographischer Gegenstände.
ULTRASONİK DESTEKLİ EKSTRAKSİYON PARAMETRELERİNİN KUŞBURNU (ROSA CANINA L.) MEYVESİNİN TOPLAM FENOLİK VE KAROTENOİD MİKTARLARI İLE ANTİOKSİDAN AKTİVİTESİ ÜZERİNE ETKİSİ
Authors: TURAN Semra , ATALAY Derya , SOLAK Rukiye , ÖZOĞUL Meliha , DEMİRTAŞ Melek
Published: May 2021

Bu çalışmanın amacı, ultrasonik ekstraksiyon parametrelerinden sonikasyon süresi (3, 6, 9, 12 ve 15 dakika), genlik (%25, 50 ve 100), sıcaklık (20, 30 ve 40°C) ve çözücü:meyve ezmesi oranlarının (5, 10 ve 15 mL/g) kuşburnunun toplam fenolik ve karotenoid miktarları üzerine etkisini belirlemektir. Ultrasonikasyon süresi artırıldığında toplam fenolik madde miktarı 3.18 mg/g değerinden 4.51 mg/g değerine; toplam karotenoid miktarı ise 4.29 mg/kg değerinden 18.70 mg/kg değerine yükselmiştir. Ultrasonikasyon genliğinin toplam karotenoid miktarı üzerine etkisi istatistiksel olarak anlamlı (P <0.05) olup, toplam fenolik madde miktarı ve antioksidan aktivite üzerine etkisi anlamlı bulunmamıştır (P >0.05). Sıcaklığın artırılması toplam fenolik madde miktarında istatistiksel olarak anlamlı (P <0.05) değişime neden olurken, toplam karotenoid miktarı ve antioksidan aktivite üzerine etkisi anlamlı olmamıştır (P >0.05). Diğer taraftan, ultrasonik ekstraksiyon sırasında çözücü:meyve ezmesi oranının artırılması daha fazla karotenoidin ekstraksiyonunu sağlamıştır. Elde edilen sonuçlara göre, ultrasonik ekstraksiyon yönteminin kuşburnu meyvesindeki biyoaktif bileşiklerin ekstraksiyonunda başarıyla kullanılabileceği belirlenmiştir.
ÇİLEK AROMASININ DEPOLAMA KARARLILIĞI ÜZERİNE PÜSKÜRTEREK KURUTMA YÖNTEMİYLE ENKAPSÜLASYON İŞLEMİNİN ETKİSİ VE MİKROKAPSÜLLERİN MODEL GIDALARDA ETKİNLİĞİNİN BELİRLENMESİ
Authors: BALCI TORUN Ferhan , OZDEMİR Feramuz
Published: May 2021

Çalışmada sıvı çilek aroması püskürterek kurutma yöntemiyle enkapsüle edilmiş ve elde edilen mikrokapsüllerin depolama stabilitesi ve model gıdalarda kullanım etkinliği belirlenmiştir. Bu amaçla mikrokapsüller farklı sıcaklıklarda (4 ve 25 °C) 60 gün süre ile depolanmış ve aroma salınımı, nem miktarı, su aktivitesi, kitle yoğunluğu ve parçacık boyutu dağılımı analizleri yapılmıştır. Ayrıca ticari sıvı ve enkapsüle çilek aromaları kullanılarak üretilen çikolata ve keklerde duyusal analizler gerçekleştirilmiştir. Çalışma sonuçları enkapsülasyon işleminin aroma salınımını yaklaşık %50 oranında azalttığını, düşük sıcaklıklardaki depolamanın aroma korunumunu daha iyi sağladığını göstermiştir.z mikrokapsüllerin nem miktarı, su aktivitesi ve parçacık boyutu değerleri depolama süresi ile birlikte artış gösterirken, kitle yoğunluğu değerinin azaldığı tespit edilmiştir. Duyusal analiz sonucunda enkapsüle çilek aromaları ile üretilen çikolata ve keklerin koku, tat, aroma ve genel beğeni açısından sıvı formda aroma kullanılarak üretilen ürünlere göre daha çok beğenildiği belirlenmiştir. Sonuçlar enkapsülasyon işleminin depolama stabilitesini arttırmasının yanında katkılandığı gıdaların işlenmesi sırasındaki kararlılıklarını da geliştirdiğini göstermiştir.
Hand rejuvenation with CaHA guided by ultrasound
Authors: Poggi Barbara
Published: May 2021

Volumizing the dorsal hand is one of the anatomical regions most frequently requested during the last decade. Calcium hydroxyapatite is the material used for this procedure since its beginning, due to its several benefits. However, despite the consensus among doctors of the dermal filler to be applied, the same does not happen to the chosen technique. This variation in methods is due to the divergence between anatomical studies in this region. Through this, we review the literature in order to establish the best method and confirming the correct plan through ultrasound to inject this material.
Realisasi Penerapan Kebijakan Protokol Kesehatan dalam Salat Berjamaah di Tempat Ibadah Pada Masa Pandemi Covid-19; Studi Kasus Kegiatan Beribadah Pada Desa Masangan Kulon, Jawa Timur dan Desa Talang Makmur, Jambi
Authors: Aziz Azalia Wardha , Wardhani Nanda Kusuma , Junaedi Junaedi
Published: May 2021

The Covid-19 pandemic since the beginning of 2020 has caused various sectors and community activities to be limited. This is done to prevent the spread of the Covid-19 virus from spreading throughout the country. Starting from teaching and learning activities, trade to worship. To return to normal activities, people are required to protect themselves and others by implementing health protocol policies. In fact, there are still many places of worship and worshipers who have not implemented health protocol policies. Therefore, this study aims to find out how to pray in congregation in places of worship during the Covid-19 pandemic and how to implement policies on implementing health protocols in congregational prayers at places of worship during the Covid-19 pandemic by researching directly at Masangan Kulon Village and Masangan Kulon Village. Prosperous Talang. The research method used in this study is a qualitative method with a case study approach. The results of the study indicate that the realization of health protocol policies in congregational prayers in places of worship during the Covid-19 pandemic has not been realized properly or has not been optimal.Keywords: Realization; Health Protocol; Congregational Prayers; Covid-19 AbstrakPandemi Covid-19  sejak awal tahun 2020 menyebabkan berbagai sektor dan kegiatan aktivitas masyarakat menjadi terbatas. Hal ini dilakukan guna mencegah penyebaran virus Covid-19 merajalela di seluruh bagian tanah air. Mulai dari kegiatan aktivitas belajar mengajar, perdagangan hingga peribadatan. Untuk kembali melakukan aktivitas seperti biasa, masyarakat dituntut untuk melindungi dirinya dan orang lain dengan menerapkan kebijakan protokol kesehatan. Pada kenyataannya, masih banyak tempat ibadah dan jamaah tempat ibadah yang belum menerapkan kebijakan protokol kesehatan. Oleh sebab itu, penelitian ini bertujuan untuk mengetahui bagaimana salat berjamaah di tempat ibadah pada masa pandemi Covid-19 dan bagaimana realisasi kebijakan penerapan protokol kesehatan dalam salat berjamaah di tempat ibadah pada masa pandemi Covid-19 dengan meneliti secara langsung pada Desa Masangan Kulon dan Desa Talang Makmur. Metode penelitian yang digunakan pada penelitian ini, adalah metode kualitatif dengan pendekatan studi kasus. Hasil penelitian menunjukkan bahwa realisasi kebijakan protokol kesehatan dalam salat berjamaah di tempat ibadah pada masa pandemi Covid-19 belumlah terealisasi dengan baik atau belum optimal.Kata Kunci: Realisasi; Protokol Kesehatan; Salat Berjamaah; Covid-19
A Study of Clinical Profile of Thyroid Disorders in Children in A Tertiary Care Hospital, Kurnool
Authors:   Assistant Professor in Peadiatrics, Viswabharathi Medical College, R. T. Nagar, Penchikalapadu, Kurnool, Andhra Pradesh, India., Ramesh Vedartham
Published: May 2021

Background: Thyroid hormone abnormalities are the commonest endocrine disorder in India and also the commonest preventable cause of mental retardation, so we want to determine the prevalence of thyroid dysfunction in children at kurnool district. Materials and Methods: A hospital based prospective observational study performed in new born and children below 18 years fulfilling the inclusion criteria visiting the pediatric OPD and IPD in Viswabharathi medical college, Kurnool if they had clinical suspicion of thyroid dysfunction. If suspicion of hypothyroidism, Free T4, Total T4, TSH levels and if suspicion of hyperthyroidism Free T3 and TSH were done. Results: Out of 70 case 3 cases (4.3%) are hyperthyroidism and 67 cases (95.7%) are hypothyroidism in these 3 (4.3%) cases had family history of thyroid disorders, male to female ratio was 1.3:6 and prevalence rate was high in the age group of 10 - 12 years 32.9% (23 cases). 13 (18.6%) cases had thyroid enlargement and 48 (68.57%) cases had anaemia. Treatment was started according to standard guidelines. Conclusion: The higher prevalence rate of thyroid disorders in childhood that to in female children and age group of 10 - 12 years in and around kurnool. Hence, screening of all new-borns and children should be mandatory as early diagnosis and treatment helps in prevention of complications of thyroid disorders. KEY WORDS: Free T3, Free T4, Goiter, Hyperthyroidism, Hypothyroidism, and Thyroid stimulating hormone.
Cooling of an Active Magnetic Bearing
Authors:   Samara State Technical University, Ivannikov Yuri , Goriachkin Aleksandr ,   Samara State Technical University, Bragin Dmitry ,   Samara State Technical University
Published: May 2021

In this paper temperature field of the magnetic bearing of a gas compressor unit was considered. A two dimension mathematical model was prepared. Model parameters were calculated with using of analytical techniques and laws of similarity. In result of numerical simulation temperature distribution of the magnetic bearing was made specific. Possibility of using of heat pipes for a magnetic bearing cooling improve was consid-ered. In result of this research temperature distribution of the magnetic bearing was identified. The particular characteristic of this a magnetic bearing design is significant influence of more hot rotor on coil thermal condition. Improve of rotor cooling based on using of heat pipes can decrease maximum temperature of rotor and coil stator. Found results can be using for development of cooling system of an active magnetic bearing.
Method for Excitation Control of Synchronous Motor in Start and Resynchronization Modes
Authors:   Donetsk National Technical University, Syvokobylenko Vitalii , Derkachev Sergey ,   Donetsk National Technical University
Published: May 2021

In the article proposed a method for excitation control of synchronous motor in the starting, self-starting and resynchronization modes, which makes it possible to increase the stability or facilitate the pulling into synchronism of heavily loaded synchronous motors due to the alternating connection of the excitation winding to an additional active resistance or to an exciter with a forced excitation voltage. For this, on the basis of the instantaneous values measurements of the phase currents and stator voltages, the reactive and active powers are determined, and using a criterion equal to the power polynomial from the power ratio, the asynchronous mode is revealed. The control of switching the excitation winding to an additional resistance or to the exciter is car-ried out using another criterion, defined as a derivative of the asynchronous mode criterion. The results of mathematical modeling are presented, which confirm that the proposed method for controlling the excitation of a synchronous motor allows one to identify the asynchronous mode of both excited and non-excited synchronous motors and provide easier resynchronization conditions by increasing the torque of the synchronous motor at low slip values, as well as to ensure successful start and retraction in synchronism loaded synchronous motor.
Research of the Influence of a Ferromagnetic Shunt on the Characteristics of the Electromagnetic Actuator of a Low-Voltage Contactor
Authors:   Platov South-Russian State Polytechnic University (NPI), Kramarov Andrey , Batishchev Denis ,   Platov South-Russian State Polytechnic University (NPI), Bolshenko Irina ,   Platov South-Russian State Polytechnic University (NPI), Gummel Andrey ,   Platov South-Russian State Polytechnic University (NPI)
Published: May 2021

The article presents the results of a research of the influence of a ferromagnetic shunt (FMS) on the static and dynamic characteristics of the control electromagnet of the KTP 6000 series contactor by means of computer numerical simulation in the ANSYS Electromagnetic Suite software package. A computer numerical model of an electromagnetic actuator with FMS is proposed and verified, the influence of the geometrical dimensions of the shunt on the static and dynamic characteristics of the electromagnetic actuator of a low-voltage DC contactor is investigated. Recommendations are given for the selection of the FMS dimensions in the design calcu-lation of the valve-type electromagnetic drive, which will increase the dynamic traction force of the electromagnet and reduce its response time.
Universal Computer Model for Studying the Dynamics of a Two-Motor Scraper Conveyor
Authors:   Tula State University, Shprekher Dmitry , Babokin Gennady ,   National research technological University «MISIS», Zelenkov Alexandr ,   Tula State University, Ovsyannikov Dmitry ,   Tula State University
Published: May 2021

The article proposes to study the dynamics of the scraper conveyor (SC), which is one of the main components of the mechanized complex of the coal face, to use a universal computer model in which the multi-mass system of the traction body (TB) with concentrated parameters is replaced by a script in the form of a MATLAB function, the code for modeling the system of equations of the TB in which is developed using the Matlab pro-gramming language. With the help of Simulink blocks, models of electric motors, transmissions, drive sprockets, as well as the elementary masses of TB are created. This solution made it possible to change the number of elementary masses in a wide range, and to ensure the study of dynamic processes in the electromechanical system of the SC with a predetermined accuracy. The most common type of multi-motor conveyor is considered: two-drive, with head and end drives connected through transmissions and sprockets by an infinite chain with scrapers. The simulation of the direct start modes at full load and empty load was carried out. The results showed that the proposed model provided 2 times faster simulation of the developed model compared to the model of a conveyor made up of the same number of individual elementary masses, while the accuracy of the simulation in terms of the speed of movement of the chain is 5% in the interval with the real conveyor. It is concluded that it is necessary to develop an effective method of controlling the head and tail drives of the scraper conveyor in order to equal their load. The results of the simulation can be used to predict the fatigue life and determine the optimal pretensioning force at an early design stage, when only a few design parameters are known.
Practical Implementation of the System of Feeder Diagnostics of Single-Phase Earth Faults with Online Distributed Data Collection
Authors:   Kazan State Power Engineering University, Fedotov Alexander , Basyrov Rafik ,   Kazan National Research Technical University, Vagapov Georgii ,   Kazan State Power Engineering University, Abdullazyanov Ainur ,   Kazan State Power Engineering University
Published: May 2021

Single-phase earth faults are one of the main problem of the distribution electrical networks with voltage 6 - 35 kV with isolated neutral. Single-phase earth fault is one of the reasons decrease of the power quality and the reliability of power supply. The paper presents the theoretical base of the monitoring parameters selection during the single-phase earth fault process and its practical implementation as an installed system at a power substation with a 110/10 kV level voltage. The hardware part of the feeder monitoring system allows implementing the determination of feeder with fault and the phase of this feeder with fault without the need to switch off of the feeders. The software part of the system allows for ongoing monitoring of feeders with built-in alarm and viewing the event archive on the supervisor computer.
Methods for Evaluating the Influence of Non-Sinusidal Voltage on Capacitor Units in Power Supply Systems
Authors:   Donetsk National Technical University, Kourennyi Eduard , Bulgakov Alexander ,   Donetsk National Technical University, Kolomytsev Arkady ,   Donetsk National Technical University
Published: May 2021

The problems of evaluating the EMC for capacitor units (CU) in power supply systems are considered. The admissible value of the current non-sinusoidal component for the CU was found, it corresponds to the actual standards. The dynamic model of the «supply line – CU» circuit has been substantiated. An equivalent circuit is given. A non-sinusoidal signal is considered as the sum of a sinusoidal and non-sinusoidal component. As a non-sinusoidal component, a voltage pulse noise model with oppositely polar periodic rectangular pulses and pauses was used. Two approaches to determine the useful signal are considered. A physically substantiated interpretation of the concept of non-sinusoidal voltage is proposed for impulse noise. Expressions are given to determine the current noise of the CU. An example of the practical calculation of voltage and current distortion is given. The graphs of the voltage impulse noise and the resulting current noise are shown. An algorithm has been developed to evaluate the effectiveness of means for reducing impulse noise.
Letter regarding “Chronic mechanical irritation and oral squamous cell carcinoma: A systematic review and meta-analysis”
Authors: Xie Jian , Li Lang
Published: May 2021

Dear Editor:

We have read with a great interest the article by Gupta et al. [1] who performed a meta-analysis exploring the association between chronic mechanical irritation and oral squamous cell carcinoma. The conclusion of the meta-analysis is that chronic oral mucosa irritation has a significant association with oral squamous cell carcinoma, and the nature of association could be that of a potential co-factor (dependent risk factor) rather than an independent risk factor.

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Protocol_mask_RCNN_CT_tensorflow v1
Authors: Yang Ching-Juei , Wang Jing-Yao
Published: May 2021

This document outlines the implementation of mask-RCNN of computed tomography under tensorflow This testing protocol includes the public medical images from "The Cancer Imaging Archive" (TCIA)(https://www.cancerimagingarchive.net/), Google Brain's Tensorflow (https://github.com/tensorflow), TensorBoard, pre-trained COCO dataset, OpenCV library under Python 3 and NVIDIA GPU. @ Ching-Juei Mark Yang @ Jing-Yao Wang May 9, 2021
The analysis of influential parameters on calibration and feeding accuracy of belt feeders
Authors: Živanić Dragan , Ilanković Nikola , Zuber Ninoslav , Đokić Radomir , Zdravković Nebojš , Zelić Atila
Published: May 2021

Continual material feeding represents a process of great importance for process industries. Feeding with belt feeders represents one of the most common methods. Belt feeders are devices that require little space, they are not expensive and, most importantly, they do not
interrupt material flow while feeding. Calibration of belt feeders, as well as other measuring devices, is a prerequisite for measuring and achieving a defined level of measurement accuracy. On the other hand, the defined level of measurement accuracy is often difficult to
achieve in practice due to the multitude of factors that affect the operation of belt feeders. Existing mathematical models indicate a number of influential factors on measurement accuracy. The paper presents the measurement procedure performed on a belt feeder in laboratory conditions, with variable speeds and belt tensions and the known raised position of the measuring idler. Based on the obtained results, appropriate conclusions were made about the influences on calibration and measurement accuracy
Hypofractioned skull base meningioma radiosurgery (case report)
Authors: Tokarev A. S. , Zuev S. E. , Rak V. A. , Stepanov V. N. , Koynash G. V. , Evdokimova O. L. , Grin A. A. , Sinitsyn V. E. , Prirodov A. V.
Published: May 2021

The objective is to describe a case of hypofractioned skull base meningioma radiosurgery.

Clinical case. For 5 years, female patient S., 55 years old, suffered from headaches. In 2012, magnetic resonance imaging of the brain showed petroclival meningioma on the left actively and homogenously accumulating the contrast agent. The patient refrained from any type of treatment. Control magnetic resonance imaging showed an increase in tumor size up to 24 × 45 × 27 mm; at the lateral margin it spread to the left temporal area, at the medial margin it grew around the left optic nerve, chiasm spreading into the left maxillary sinus. We performed three-fraction radiosurgery for skull base meningioma according to hypofractionation scheme (7 Gr / fraction with 2 day interval). 37 months postoperatively, tumor volume had complete regression. There are no optic disturbances.

Conclusion. This case report demonstrates treatment results of difficult structure tumor and describe radiosurgical possibilities in big size meningiomas.
Neurofibromatosis 2: new perspectives in treatment (case report)
Authors: Makashova E. S. , Zolotova S. V. , Kostyuchenko V. V. , Galkin M. V. , Ginzberg M. A. , Danilov G. V. , Antipina N. A. , Konovalov N. A. , Golanov A. V.
Published: May 2021

Neurofibromatosis 2 is one of the most prevalence disease among phakomatoses characterized by appearance of new central and peripheral nerve system tumors. The main treatment for this patient is a surgery, but in real time we observe the significant changes in treatment and rehabilitation in this patients including radiation therapy and pharmacotherapy. In this paper, we present the case of a different treatment options in young female with neurofibromatosis. She completed surgical treatment, Gamma Knife radiosurgery and bevacizumab on different stage of disease. Development of genetic and molecular methods and appearance of new way for treatment could help to achieve a good functional result and stable local control but new clinical and fundamental research are needed.
A case of successful surgical treatment of a patient with a cement embolism of the right heart chambers after vertebroplasty
Authors: Muratov R. M. , Khramchenkov A. G. , Sachkov A. S. , Babenko S. I. , Meshchanov B. V.
Published: May 2021

Cement embolism of the right chambers of the heart after vertebral surgery is an extremely rare complication and occurs in 4 % of cases. The strategies for choosing the treatment of this complication are open-heart surgery under conditions of cardiopulmonary bypass, conservative treatment, or endovascular support. In the case of a fatal complication of embolism, such as perforation of the heart with the development of tamponade or life-threatening arrhythmias, the patient is shown an open operation with infrared. According to the literature, only 14 such operations are described, performed to save the patient’s life. We performed a successful operation of embolectomy from the right heart chambers in a 69‑year-old patient who had previously undergone vertebroplasty of the thoracic vertebrae.
High-grade gliomas: a literature review. Part 1. Epidemiology, classification and approaches to combination treatment
Authors: Gretskikh K. V. , Tokarev A. S.
Published: May 2021

Malignant brain tumors remain one of the most complex problem in modern oncology, being among the most dangerous types of cancer not only because of their poor prognosis, but also due to the immediate consequences for quality of life and cognitive functions. It is expected that the number of such patients will increase as the life expectancy of the population increases.

The mortality rate of patients with malignant gliomas remains the highest among all cancer patients. The median survival rate in this population does not exceed 24.5 months. Despite serious progress in the study of the molecular biology of this type of tumor, the question of effective application of this knowledge in the treatment process remains open.

The review highlights the most advanced diagnostic methods and analyzes the effectiveness of a multidisciplinary therapeutic strategy. Special attention is given to the search for new approaches to radiosurgical treatment of highgrade gliomas in order to increase the duration and improve the quality of life of patients.

The literature review is divided into 2 parts. Part 1 covers the epidemiology, clinic, and diagnosis of high-grade gliomas, as well as a combined approach to the treatment of the disease.
Magnetic resonance imaging in the diagnosis of brain arteriovenous malformations and in the evaluation of the results of stereotactic radiosurgery (review)
Authors: Tokarev A. S. , Chuvilin S. A. , Neznanova M. V.
Published: May 2021

Arteriovenous malformations (AVM) are quite rare, but they are dangerous pathology due to the risk of rupture and intracranial hemorrhage, which leads to disability. This review enlights the epidemiology of AVM and their symptoms, current methods of diagnostics and treatment as well as prognosis and treatment outcomes. Nowadays microsurgical removal, endovascular embolization, stereotactic radiosurgery and combination of these methods are used in clinical practice for AVMs treatment. Stereotactic radiosurgery is a highly effective non-invasive technique resulting in high degree of AVM obliteration with low risk of complications. The results of magnetic resonance imaging usage in assessing the degree of obliteration and the development of post-radiation complications are presented in this article. The optimization of magnetic resonance imaging algorithm is necessary for determination of statistically significant factors affecting the obliteration process.
Tandem spinal stenosis: clinical pattern, diagnosis and surgical tactics
Authors: Feniksov V. M. , Zelenkov P. V.
Published: May 2021

The purpose of this review is to present an up-to-date look at the features of diagnosis and treatment of tandem spinal stenosis. Tandem spinal stenosis is a degenerative narrowing of the spinal canal of two or more parts of the spine column. Diagnosis of the one-level degenerative spinal stenosis is commonly quite easy in the practice of a spinal surgeons, while the diagnosis of tandem spinal stenosis is often difficult. The clinical presentation of tandem spinal stenosis presents a constellation of different symptoms and often cause late diagnosis. Data on the prevalence of tandem spinal stenosis are very variable, and the etiology cannot be fully studied. Thereby, comprehensive assessments of the symptoms and imaging provide assistance with the accurate and timely diagnosis. The choice of surgical method should consider possibility of staged decompression of each stenotic levels with priority for proximal parts of spine column.
Staged radiosurgery in the managment of patients with brain metastases
Authors: Osinov I. K. , Golanov A. V. , Banov S. M. , Artemenkova A. E. , Kostuchenko V. V. , Dalechina A. V.
Published: May 2021

The study objective is to present the results of the treatment of metastatic brain patients by the staged radiosurgery with the Gamma Knife.

Materials and methods. The retrospective analysis included 31 patients (13 men and 18 women) with brain metastases, whose radiosurgery treatment was carried out in 2 sessions. The operation was contraindicated in all patients due to the risk of neurological deficits or due to the high anesthesiological risk.

Results. Local control of metastases growth was achieved in 31 (96.9 %) of 32 foci 3 months after treatment, and in 92.5 and 83.8 %, after 6 and 12 months, respectively. The age <50 years were associated with higher progression-free survival respectively. The median time of grade I–II radiation complications was 3.0 months, complications were observed in 11 (45.8 %) of 24 patients. Radiation complications of grade II (perifocal edema) were observed in 8 (33.3 %) patients, grade III (radionecrosis) – in 2 (8.3 %) patients. Overall survival at 6 and 12 months was 55.6 and 40.8 %, respectively (median 6.9 months), in patients receiving antitumor drug treatment – 80.0 and 56.8 %, respectively. All patients who did not received antitumor drug therapy died within 6 months.

Conclusion. Two-stage radiosurgery, carried out in 2 sessions with an interval of 2–4 weeks, provides satisfactory local control with an acceptable level of post-radiation complications. This method of treatment can be used in patients with large brain metastases who are not subject to surgical treatment.