bluuebunny/crossref_metadata_2025_split huggingface dataset:
Calcification of bioprosthetic heart valves treated with ethylene glycol diglycidyl ether
Authors: Glushkova T. V. , Kostyunin A. E. 
Published: June 2021

Highlights. The morphology and elemental composition of calcium deposits formed in the tissues of epoxytreated aortic and mitral bioprostheses do not differ from those in the mineralized matrix of stenotic human aortic valve leaflets. Despite similar elemental composition of mineral deposits in the KemCor and UniLine bioprostheses, the morphology of these calcifications differs between bioprosthetic heart valve substitutes and, apparently, is associated with the specific structure of the fibrous matrix of the biological tissues that are used for their manufacturing.Aim. To analyze the morphology and elemental composition of mineral deposits formed in epoxy-treated aortic and mitral bioprosthetic heart valves made from xenoaortic or xenopericardial material and to compare the obtained findings with the data on calcified human aortic valve.Methods. Leaflets of the mitral and aortic bioprosthetic heart valves KemCor and UniLine (NeoKor, L Russia, Kemerovo) that were explanted due to their failure, as well as leaflets of the calcified native aortic valve were evaluated. The morphology of calcifications was studied by scanning electron microscopy using an S-3400N microscope (Hitachi, Japan). The elemental composition of calcium deposits was studied by electron probe microanalysis using Hitachi S-3400N microscope with energy dispersive spectrometer Bruker XFlash 4010 (Bruker, Germany).Results. Large calcifications located at the internal layers of samples were surrounded by collagen fibers commonly with evident signs of the onset of mineralization. Calcium deposits in the native aortic valve and xenoartic bioprostheses KemCor were located mainly at the spongy layer and had a loose structure, while dense lamellar deposits were found at the leaflets of pericardial bioprostheses UniLine. The elemental composition of calcium deposits showed the presence of Ca, P, O, Mg, and Na in the mineralized regions and the presence of S in the regions of low electron density. The calcium to phosphorus ratio (Ca:P) in the calcifications of the aortic valve leaflets was 1.81 (1.79-1.84; min - 1.48; max - 2.05), whereas the Ca:P ratios in the UniLine and KemCor bioprostheses were 1.78 (1.75-1.86; min - 1.52; max - 2.03) and 1.82 (1.81-1.88; min - 1.71; max - 2.06), respectively. There were no significant differences in the Ca:P ratios between calcifications in the study groups (p>0.05).Conclusion. Calcium deposits detected in epoxy-treated bioprostheses and human aortic valve appeared to be formed under dystrophic calcification. The morphology of calcifications in bioprostheses depended on the type of biological tissue. None correlations between the morphological structure of calcifications and the implantation position were found in bioprosthetic leaflets. The elemental composition of mineral deposits was similar in all study samples.
Risk factors for the occurrence of typical atrial flutter in patients undergoing pulmonary vein isolation
Authors: Safonov N. V. , Baranovich V. Yu. , Faibushevich A. G. 
Published: June 2021

Highlights. Cavatricuspid isthmus ablation with pulmonary vein isolation is indicated to all patients with documented or intraoperatively induced typical atrial flutter. The preventive cavatricuspid isthmus ablation remains an issue of concern. The article discusses the risk factors for the onset of typical atrial flutter pulmonary vein isolation.Aim. To determine the need for preventive ablation of the cavatricuspid isthmus in patients referred to elective pulmonary vein isolation.Methods. 632 patients (the mean age of 63 years) were enrolled in a single-center retrospective study between 2015 to 2018. The inclusion criteria were as follows: paroxysmal AF, absence of documented AFL. All patients underwent pulmonary vein isolation. The exclusion criteria were as follows: a history of typical or AFL. The endpoints included major cardiovascular events, reoperations, occurrence of AFL. The primary endpoint was the absence of paroxysms of AF and AFL during the blind period. The secondary endpoint was the absence of AF paroxysms documented on the ECG or according to Holter monitoring data. The follow-up period was 12 months.Results. During the blind period, AF paroxysms were recorded in 148 (23.7%) patients. The efficiency of the operation within one year was 78.2% (494 patients). 138 patients (21.8%) had recurrent tachycardia. Of them, 28 patients (4.4%) were diagnosed with atrial fibrillation and others (17.4%) had AFL. Risk factors for AFL included COPD found in 18 patients (64.29%) (OR 25.4; CI 95%; 10.991-58.609), chronic heart failure in 20 patients (71.43%) (OR 7.434; CI 95%; 3.209-17.225), prolonged pr interval in 18 patients (64.29%) (OR 5.77; CI 95%; 2.288-14.5), a history of myocardial infarction in 6 patients (28.57%) (OR 6.591; CI 95%; 2.447-17.751), and smoking in 7 patients (67.86%) (OR 11.034; CI 95%; 4.849-25.112).Conclusion. Chronic obstructive pulmonary disease, chronic heart failure, a history of myocardial infarction, and smoking prolong right atrial conduction time, thereby increasing the risk of AFL in the postoperative period. Preventive cavatricuspid isthmus ablation should be considered in patients with risk factors for developing AFL.
Remote outpatient follow-up of patients with arterial hypertenson: the role of a nurse
Authors: Strokolskaya I. L. , Kilizhekova D. V. , Artamonova G. V. 
Published: June 2021

Highlights. Telehealth remote monitoring for patients with arterial hypertension has been developed and implemented. A nurse coaching approach has been reported.Aim. To develop and implement the technology of remote dispensary observation of patients with arterial hypertension (AH) using telemedicine, in which the main performer is a clinic nurse.Methods. The research object is patients with AH who are under dispensary observation at the territorial polyclinic. The study included 183 patients aged 53±12.5 years, of which 64.5% were women. The duration of observation is from 30 to 90 days. The effectiveness was evaluated on the basis of the achievement of target values of blood pressure (BP), number of visits to the doctor for hypertension decompensation, patient compliance. The program used data processing technology applying telemedicine devices for automatic BP measurement.Results. In 75.5% of cases, there was a decrease in the average level of systolic and diastolic BP in comparison with the initial levels. A decrease in the maximum systolic BP and in the frequency of decompensation episodes of BP above 160 mm Hg was recorded in 15.8% of patients. Achievement of the target BP level was identified in 64.2% of patients, in 11.3% there was a positive dynamic in the clinical condition without achieving the target figures, in 24.5% of cases, no dynamics was found. The majority of patients (84.2%) preferred remote forms of counseling while maintaining a stable level of indicators. Among 15.8% of patients, the number of visits to a doctor decreased from 2.0 to 0.75 visits per month. High adherence to preventive measures was observed in 88.7% of cases; 100% of patients in the observation group confirmed the use of prescribed antihypertensive drugs.Conclusion. The original technology of remote dispensary observation of patients with AH using telemedicine devices enhances the continuity in “doctor-nurse-patient” interactions, which contributes to the improvement of medical efficiency by increasing the proportion of patients in the dispensary group who have reached the target level of BP and increase the patients' adherence to preventive measures. Telemedicine technologies reduce the number of scheduled and urgent patient visits to a polyclinic, which is relevant in the context of the shortage of medical personnel and the transition to remote consultation due to the restrictions caused by the epidemic threat [17].
Migrações internacionais de jovens rurais: limites da reprodução social de agricultores familiares e construções da autonomia pessoal / International migration of rural youth: limits of family farmers social reproduction and constructions of personal auto
Authors: Marin Joel Orlando Bevilaqua , Drebes Laila Mayara 
Published: June 2021

O artigo tem como objetivo compreender o fenômeno das migrações internacionais vividas por jovens rurais, a partir da inter-relação de fatores objetivos e subjetivos que interferem na reprodução familiar de agricultores. A pesquisa foi realizada em Itapuranga, estado de Goiás, com base em dados qualitativos, obtidos por meio de entrevistas semiestruturadas. As migrações internacionais estão relacionadas com a desestruturação da produção agrícola e dos meios de vida dos agricultores familiares, que limitam a construção da autonomia dos jovens rurais e de processos de sucessão hereditária. Ancoradas em longa tradição, as migrações internacionais de jovens rurais passaram a representar estratégias de ascensão social, emancipação pessoal e transição para a vida adulta. In this article, we aim to analyze the phenomenon of international migrations experienced by rural young people, based on the interrelationship between objective and subjective factors that limit the traditional strategies of social reproduction in agriculture and the construction processes of social autonomy and entry into adult life. The research was carried out in Itapuranga, state of Goiás, Brazil, based on qualitative data, obtained through semi-structured interviews. International migrations are related to the disruption of agricultural production and the livelihoods of family farmers and to changes in perceptions of rural life and work, which limit the processes of hereditary succession and the construction of the autonomy of rural youth. Anchored in a long tradition, the international migrations of rural youth have begun to represent strategies of social ascension, personal emancipation and transition to adult life.
Percursos migratórios nos territórios da costura / Migratory routes in the sewing territories
Authors: Freitas Patrícia Tavares de 
Published: June 2021

Neste artigo, abordaremos os percursos migratórios de bolivianos e bolivianas no interior dos territórios da costura em São Paulo e Buenos Aires. A partir de uma caracterização dessa migração como território circulatório, argumentamos ser necessária a compreensão das formas como os migrantes articulam, em sua experiência social, os vários fatos de mobilidade que compõem seus percursos migratórios na costura. Para tanto, propomos a metodologia das narrativas de vida como narrativas de práticas. Finalizamos o artigo com a apresentação de dois percursos típicos: i) aqueles que se integram de fato em uma das sociedades de destino, apresentando pouca probabilidade de retorno, mesmo quando seguem engajados nos territórios da costura e, ii) aqueles que retornam para a Bolívia após uma primeira experiência, com alta probabilidade de reinserção nos territórios da costura. In this article, we will approach the migratory routes of Bolivians within the sewing territories in São Paulo and Buenos Aires. Based on a characterization of this migration as a circulatory territory, we argue that it is necessary to understand the ways in which migrants articulate, in their social experience, the various mobility facts that make up their migratory routes in sewing territories. Therefore, we propose the methodology of life narratives as narratives of practice. To conclude, we present two typical routes: i) those who actually integrate into one of the destination cities, presenting little probability of return, even when they remain engaged in the sewing territories and; ii) those who return to Bolivia after a first experience, with a high probability of reintegration in the sewing territories.
FST-Convoy: A Leader Tracking Control of Vehicles Connected by Shape Sensor FST
Authors: Ura Daisuke ,   Osaka University Central Terrace 5F, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan, Masumoto Kotaro , Osuka Koichi 
Published: June 2021

This paper describes FST-Convoy, a leader tracking control system for vehicles using the shape sensor flexible sensor tube (FST).	Among many methods of autonomous driving, follow-driving is one of them.	Some of these have been put into practical use in a limited environment.	Unfortunately, there are situations in which such sensors do not work well.	One of these is underground.	In the underground, GNSS signals do not reach vehicles, so they cannot obtain their positions.	Therefore, we propose a new way to achieve follow-driving in such environments.	We used the shape sensor, FST.	The FST is a shape sensor with a serial link structure and many joints.	It can measure its shape by solving its kinematics and determine the relative position of the start link to the end link.	Therefore, we can measure the relative positions of vehicles that connected a leader and a follower using FST.	We call this system FST-Convoy.	We developed and verified the system using a platooning-driving experiment.
Factors in Teachers’ Awareness of Pedagogical Gestures as Enhancement Technique Among English Teachers in Secondary Schools in Enugu State, Nigeria
Authors: Iwe Nkechinyere 
Published: June 2021

The study seeks to ascertain Nigerian language teachers’ awareness of pedagogical gestures as an enhancement to teaching and whether this awareness is influenced by teaching location and teacher qualification. The study adopts the survey research design with a sample size of 262 drawn using multi-staged sampling techniques. The Z-test method was used in testing the hypothesis of the study. It was discovered that there was high mean response of teachers on the awareness of pedagogical gestures. There were significant differences in the mean response of urban/rural teachers and no significant differences in the mean response of graduate/non-graduate teacher’s awareness of pedagogical gestures as enhancement technique. Our conclusion is that pedagogical gestures are indispensable in lesson delivery and that their pedagogic values are gained through awareness of them as enhancement technique.
The Influence of Trap Magmatism on the Geochemical Composition of Brines of Petroliferous Deposits in the Western Areas of the Kureika Syneclise (Siberian Platform)
Authors: Novikov D.A. , Gordeeva A.I. , Chernykh A.V. , Dultsev F.F. , Zhitova L.M. 
Published: June 2021

Abstract
—We present the results of study of the influence of trap magmatism on the geochemical composition of brines and on the geothermal regime of the Earth’s interior in the western areas of the Kureika syneclise. The Siberian trap province, which unites all cutting and layered tholeiite–basic magmatic intrusions and erupted basaltic lava, is the world’s largest Phanerozoic continental basalt province. Brines, hydrocarbon deposits, and organic matter of the sedimentary cover were subjected to a significant thermal impact as a result of the Permo-Triassic trap magmatism. During the trap intrusion, the maximum paleotemperatures in major Silurian (D’yavolskii), Ordovician (Baikit), and Cambrian (Deltula–Tanachi, Abakun, and Moktakon) productive horizons reached 650 °C. The Paleozoic and Proterozoic deposits of the study area contain brines with TDS = 50–470 g/dm3. By chemical composition, they are of Na, Na–Ca, Ca–Na, Ca–Mg, and Ca chloride types (according to the classification by S.A. Shchukarev), with mixed Ca–Na and Na–Ca chloride brines dominating. The studied brines can be divided into three groups according to the degree of metamorphism: low (S1), medium (S2), and high (S3). The first group includes mainly sodium chloride brines with TDS = 50–370 g/dm3 (rNa/rCl = 0.60–0.95; S ≤ 100). The second (dominating) group comprises Na–Ca, Ca–Na, Ca, and Ca–Mg chloride brines with TDS = 150–470 g/dm3 (rNa/rCl = 0.10–0.87; 100 ≤ S ≤ 300). The third group is Ca–Na and Ca chloride brines with TDS = 223–381 g/dm3 (rNa/rCl = 0.12–0.45; S ≥ 300). We have first established changes in the hydrogeochemical field (major- and trace-component and gas compositions) with distance from the contacts of intruded dolerite sills and dikes. Hydrocarbons (CH4, C2H6, C3H8, i-C4H10, n-C4H10, i-C5H12, n-C5H12, and C6H14) and water-soluble components I, B, and NH4 were most actively subjected to destruction. For example, at a distance of 100 m from the intrusion zone, the water-dissolved gases are dominated by CO2 (&gt;90 vol.%), and CH4 amounts to 5 vol.%, whereas at a distance of 250 m, the concentration of CO2 decreases to 30 vol.%, and that of CH4 increases to 60–70 vol.%. In addition to the negative effect on the hydrocarbon preservation in the contact zone (≤400 m), the intrusive trap magmatism favored the formation of hydrocarbons in remote horizons. The reaction of intruding traps with brines of the sedimentary cover led to the saturation of the latter with iron, aluminum, and silica, which suggests extraction of metals in the form of salts from magmatic melts into an ore-bearing fluid.
The Akhunovo–Petropavlovsk Granitoid Area as a Continental-Margin Center of the Long-Term Mantle–Crust Interaction: The Role of Subductional and Rift–Plume Sources
Authors: Kholodnov V.V. , Shagalov E.S. , Kallistov G.A. , Shardakova G.Yu. , Salikhov D.N. , Konovalova E.V. 
Published: June 2021

Abstract
—The Akhunovo–Petropavlovsk area of the late Paleozoic granite magmatism is located in the northeast of the Magnitogorsk megazone (MMZ) in the South Urals. It is a series of successively intruded rocks (Petropavlovsk, Akhunovo, Karagai, and Uiskii Bor intrusions) differing not only in composition, the depth of formation, and ore content but also in the relationship with magmatic and fluid sources and in magma generation mechanisms. This area differs significantly in the number and composition of intrusive complexes from the igneous rocks and ore associations in the central and western parts of the MMZ. The granite magmatism pulses alternated with the collisional shearing/spreading and rifting stages. The Petropavlovsk mesoabyssal granite intrusion (347.0 ± 8.6 Ma) formed at the early stage of the area evolution. Its rocks are similar in composition to a suprasubductional series (melting products of a mantle source enriched not only in water fluid but also in Cl). Later (310–306 Ma), at the collision–compression stage, crustal intrusion of the Akhunovo–Karagai granodiorite–granite complex took place. The intruded rocks are similar to the Middle Urals continental-margin gabbro-tonalite–grano-diorite–granite plutons (320–290 Ma) bearing large gold–sulfide–quartz deposits (Berezovskoe etc.). At the final stage of the area evolution, during the transition from continental-margin regime to hard collision between the East European and Kazakhstan continents (late Carboniferous) and the intense shearing/spreading deformations, the Uiskii Bor granosyenite–granite intrusion (304.0 ± 4.8 Ma) rich in K and HFSE formed. Granite intrusions of this type have been revealed in the MMZ for the first time. Thus, the granitoid complexes of the Akhunovo–Petropavlovsk area formed under changes in geodynamic settings and are characterized by different compositions, depths of occurrence, and genesis. This permits us to consider the area a typical continental-margin center of the long-term mantle–crust interaction, where magma generation proceeded at different mantle and crust levels, with the participation of both suprasubductional and enriched plume-related rift sources.
Petrogenesis of the Despen Volcanic Rocks of the Middle–Late Ordovician Volcanoplutonic Association of the Tannu-Ola Terrane (Southwestern Tuva)
Authors: Vetrov E.V. , Uvarov A.N. , Vetrova N.I. , Letnikov F.A. , Vishnevskaya I.A. , Zhimulev F.I. , Andreeva E.S. , Chervyakovskaya M.V. 
Published: June 2021

Abstract
––We have studied the structure and composition of a volcanic unit in the valley of the Despen River, on the southern slope of the East Tannu-Ola Ridge. The unit was earlier assigned to the Lower Devonian Kendei Formation. The new geological and geochronological data show that it resulted from explosive volcanism at 460–450 Ma. The Despen volcanic rocks formed in association with granitoids of the Argolik complex at the end of the accretion–collision stage of evolution of the Altai–Sayan region, in particular, the Tannu-Ola terrane. These are predominantly felsic ferroan metaluminous and weakly peraluminous nappe volcanic rocks resulted from the differentiation of tholeiitic basalts. Their REE patterns, like those of the Argolik granitoids, are flat in the HREE, show a distinct Eu anomaly, and suggest magma generation at shallow depths in the upper crust. The magmatic source was of subduction origin, as evidenced by the negative Ta–Nb anomalies in the multielement patterns and by εNd(T) = +3.1 to +5.6, and has a Neoproterozoic model age, TNd(DM-2st) = 0.94–0.69 Ga.
Chimeric Virus-like Particles of Universal Antigen Epitopes of Coronavirus and Phage Qβ Coat Protein Trigger the Production of Neutralizing Antibodies
Authors: Guo Yukun , Guo Ruizhen , Ma Yingxian , Chang Wenru , Ming Shengli , Yang Guoyu , Guo Yujie 
Published: June 2021

Background:
Virus-like Particles (VLPs) are non-genetic multimeric nanoparticles synthesized
through in vitro or in vivo self-assembly of one or more viral structural proteins. Immunogenicity
and safety of VLPs make them ideal candidates for vaccine development and efficient
nanocarriers for foreign antigens or adjuvants to activate the immune system.

Aims:
The present study aimed to design and synthesize a chimeric VLP vaccine of the phage Qbeta
(Qβ) coat protein presenting the universal epitope of the coronavirus.

Methods:
The RNA phage Qβ coat protein was designed and synthesized, denoted as Qbeta. The
CoV epitope, a universal epitope of coronavirus, was inserted into the C-terminal of Qbeta using
genetic recombination, designated as Qbeta-CoV. The N-terminal of Qbeta-CoV was successively
inserted into the TEV restriction site using mCherry red fluorescent label and modified affinity purified
histidine label 6xHE, which was denoted as HE-Qbeta-CoV. Isopropyl β-D-1-thiogalactopyranoside
(IPTG) assessment revealed the expression of Qbeta, Qbeta-CoV, and HE-Qbeta-CoV in
the BL21 (DE3) cells. The fusion protein was purified by salting out using ammonium sulfate and
affinity chromatography. The morphology of particles was observed using electron microscopy.
The female BALB/C mice were immunized intraperitoneally with the Qbeta-CoV and HE-Qbeta--
CoV chimeric VLPs vaccines and their sera were collected for the detection of antibody level and
antibody titer using ELISA. The serum is used for the neutralization test of the three viruses of
MHV, PEDV, and PDCoV.

Results:
The results revealed that the fusion proteins Qbeta, Qbeta-CoV, and HE-Qbeta-CoV could
all obtain successful expression. Particles with high purity were obtained after purification; the
chimeric particles of Qbeta-CoV and HE-Qbeta-CoV were found to be similar to Qbeta particles in
morphology and formed chimeric VLPs. In addition, two chimeric VLP vaccines induced specific
antibody responses in mice and the antibodies showed certain neutralizing activity.

Conclusion:
The successful construction of the chimeric VLPs of the phage Qβ coat protein presenting
the universal epitope of coronavirus provides a vaccine form with potential clinical applications
for the treatment of coronavirus disease.