71 research outputs found

    Synthesis of 2-((3-(ethoxycarbonyl)-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)amino)-4-(4-methoxyphenyl)-4-oxobut-2-enoate

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    Will be discussed synthesis of 2-((3-(ethoxycarbonyl)-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)amino)-4-(4-methoxyphenyl)-4-oxobut-2-enoate.The work was supported by an RFBR grant 19-43-590023

    Synthesis of 2-((3-(ethoxycarbonyl)-4,5,6,7-tetrahydrobenzo [b] thiophen-2-yl)amino)-4-(4-methoxyphenyl)-4-oxobut-2-enoate

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    2-((3-(Ethoxycarbonyl)-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)amino)-4-(4-methoxyphenyl)-4-oxobut-2-enoate has been synthesized by the reaction of ethyl (E)-2-((5-(4-methoxyphenyl)-2-oxofuran-3(2H)-ylidene)amino)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate or 2-((3-(ethoxycarbonyl)-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)amino)-4-(4-methoxyphenyl)-4-oxobut-2-enoate with potassium tert-butoxide. © 2022 Author(s).The work was done with the financial support of the Russian Foundation for Basic Research (project no. 19-43-590023)

    Use of nano-sized components in multilayer composite materials

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    Introduction. In our country, the use of composite materials for creating parts and structural components in the construction industry is not as widespread as it could be. Composite materials are multilayer structures made of reinforcing fibers, impregnated with a polymer binder, which is also an adhesive. The strength properties of layered structural materials are achieved through various reinforcing fillers and adhesive binders. Both glass fibre and carbon fibre fabrics and fibers themselves are widely available as layered materials. Various thermosetting resins (epoxy, phenolic, polyester, polyimide, polyamideimide, polyamide, etc.) are used as binding components. Among them, epoxy resins with high strength, wettability and adhesion to various materials are widely used. Layered composite materials (LCM) are used to make polymer reinforcement for reinforcing concrete structures, various pipes, shell frames to strengthen existing metal and reinforced concrete structures, load-bearing elements in light-loaded structures of bridges and crossings. However, at the same time they have a significant drawback – low interlayer strength (propensity to layering). As a result, the connection between the layers is disrupted, which leads to a significant decrease in the rigidity and strength of the structure. This phenomenon applies to all types of fabrics and fibers. Most often, defects in the form of layering are formed under the influence of shock loads. To improve the performance characteristics of such materials, various fillers have now begun to be used – powders (micro- and nano-sized) introduced into binder compositions. Main part. The analysis of the academic literature has shown that it is possible to increase the interlayer strength in structural elements made of LCM through the use of nanofilled binders and the introduction of nanoadditives into the interlayer space of layered materials. The article reviews the related inventions in Russia, USA, etc., which can be applied in the construction industry using nanodispersed components. With the widespread use of the presented materials (in bridges, pedestrian bridges and bridge decks, etc.), significant performance advantages can be achieved compared to materials traditionally used in the construction industry. Methods and materials. By comparing the data from the submitted patents for inventions, it was revealed that the introduction of from 2% to 5% of various nanocomponents to form a nanocomposite material provides a new means of modifying the physical properties of polymer binders. Results. It was revealed that the use of nanoparticles ensures the decrease in the fluidity of prepregs and the gelation time, and the increase in residual compressive strength and specific fracture energy – indicators characterizing the crack resistance of composite materials. As a result, fracture toughness, endurance and survivability increase. Conclusion. Increasing the reliability of composite materials leads to longer service life of products and structural elements in the construction industr

    Organizational evolution and the Olympic Games: the case of sport climbing

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    This paper discusses the processes underpinning the evolutionary development of sport climbing in recent decades, with a particular focus on the impact of its inclusion in the Olympic Games. New institutionalism and resource-dependence theory provide an analytical and explanatory framework for this study. The research adopted a qualitative method strategy comprising a series of interviews and the analysis of documents, reports, press and social media. The recent inclusion of the sport in the Tokyo 2020 Olympic programme has created challenges, primarily because of strong values inherent within the sport. The research, however, shows that the values of a sport can expand and develop in order to fit the regulatory legitimacy required by inclusion in the Olympic Games. Nonetheless, the research also shows that involvement with the IOC raises questions about who ‘owns’ the sport

    The role of prefrontal cortex in working-memory capacity, executive attention, and general fluid intelligence: An individual-differences perspective

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    Training during the COVID-19 lockdown : knowledge, beliefs, and practices of 12,526 athletes from 142 countries and six continents

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    OBJECTIVE Our objective was to explore the training-related knowledge, beliefs, and practices of athletes and the influence of lockdowns in response to the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS Athletes (n = 12,526, comprising 13% world class, 21% international, 36% national, 24% state, and 6% recreational) completed an online survey that was available from 17 May to 5 July 2020 and explored their training behaviors (training knowledge, beliefs/attitudes, and practices), including specific questions on their training intensity, frequency, and session duration before and during lockdown (March–June 2020). RESULTS Overall, 85% of athletes wanted to “maintain training,” and 79% disagreed with the statement that it is “okay to not train during lockdown,” with a greater prevalence for both in higher-level athletes. In total, 60% of athletes considered “coaching by correspondence (remote coaching)” to be sufficient (highest amongst world-class athletes). During lockdown, < 40% were able to maintain sport-specific training (e.g., long endurance [39%], interval training [35%], weightlifting [33%], most (83%) training for “general fitness and health maintenance” during lockdown. Athletes trained alone (80%) and focused on bodyweight (65%) and cardiovascular (59%) exercise/training during lockdown. Compared with before lockdown, most athletes reported reduced training frequency (from between five and seven sessions per week to four or fewer), shorter training sessions (from ≄ 60 to < 60 min), and lower sport-specific intensity (~ 38% reduction), irrespective of athlete classification. CONCLUSIONS COVID-19-related lockdowns saw marked reductions in athletic training specificity, intensity, frequency, and duration, with notable within-sample differences (by athlete classification). Higher classification athletes had the strongest desire to “maintain” training and the greatest opposition to “not training” during lockdowns. These higher classification athletes retained training specificity to a greater degree than others, probably because of preferential access to limited training resources. More higher classification athletes considered “coaching by correspondence” as sufficient than did lower classification athletes. These lockdown-mediated changes in training were not conducive to maintenance or progression of athletes’ physical capacities and were also likely detrimental to athletes’ mental health. These data can be used by policy makers, athletes, and their multidisciplinary teams to modulate their practice, with a degree of individualization, in the current and continued pandemic-related scenario. Furthermore, the data may drive training-related educational resources for athletes and their multidisciplinary teams. Such upskilling would provide athletes with evidence to inform their training modifications in response to germane situations (e.g., COVID related, injury, and illness).A specific funding was provided by the National Sports Institute of Malaysia for this study.The National Sports Institute of Malaysia.https://www.springer.com/journal/40279am2023Sports Medicin

    COVID-19 lockdown : a global study investigating athletes’ sport classification and sex on training practices

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    PURPOSE : To investigate differences in athletes’ knowledge, beliefs, and training practices during COVID-19 lockdowns with reference to sport classification and sex. This work extends an initial descriptive evaluation focusing on athlete classification. METHODS : Athletes (12,526; 66% male; 142 countries) completed an online survey (May–July 2020) assessing knowledge, beliefs, and practices toward training. Sports were classified as team sports (45%), endurance (20%), power/technical (10%), combat (9%), aquatic (6%), recreational (4%), racquet (3%), precision (2%), parasports (1%), and others (1%). Further analysis by sex was performed. RESULTS : During lockdown, athletes practiced body-weight-based exercises routinely (67% females and 64% males), ranging from 50% (precision) to 78% (parasports). More sport-specific technical skills were performed in combat, parasports, and precision (∌50%) than other sports (∌35%). Most athletes (range: 50% [parasports] to 75% [endurance]) performed cardiorespiratory training (trivial sex differences). Compared to prelockdown, perceived training intensity was reduced by 29% to 41%, depending on sport (largest decline: ∌38% in team sports, unaffected by sex). Some athletes (range: 7%–49%) maintained their training intensity for strength, endurance, speed, plyometric, change-of-direction, and technical training. Athletes who previously trained ≄5 sessions per week reduced their volume (range: 18%–28%) during lockdown. The proportion of athletes (81%) training ≄60 min/session reduced by 31% to 43% during lockdown. Males and females had comparable moderate levels of training knowledge (56% vs 58%) and beliefs/attitudes (54% vs 56%). CONCLUSIONS : Changes in athletes’ training practices were sport-specific, with few or no sex differences. Team-based sports were generally more susceptible to changes than individual sports. Policy makers should provide athletes with specific training arrangements and educational resources to facilitate remote and/or home-based training during lockdown-type events.https://journals.humankinetics.com/view/journals/ijspp/ijspp-overview.xmlhj2023Sports Medicin
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