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BACKGROUND:Critical energy release rate is a global fracture parameter that could be measured during the failing process,and its value may change under different failure modes even in the same structure. OBJECTIVE:To propose an approach to predict the critical energy release rate in the femoral cortical bone structure under different failure modes. METHODS:Three-point bending and axial compression experiments and the corresponding fracture simulations were performed on the rat femoral cortical bone structures.Different critical energy release rates were repeatedly assigned to the models to perform fracture simulation,and the predicted load-displacement curves in each simulation were compared with the experimental data to back-calculate the critical energy release rate.The successful fit was that the differences in the fracture parameters between the predicted and experimental results were less than 5%. RESULTS AND CONCLUSION:(1)The results showed that the cortical bone structure occurred tensile open failure under three-point bending load,and the predicted critical energy release rate was 0.16 N/mm.(2)The same cortical bone structure occurred shear open failure under axial compression load,and the predicted critical energy release rate was 0.12 N/mm,which indicates that the critical energy release rate of the same cortical bone structure under different failure modes was different.(3)A comprehensive analysis from the perspectives of material mechanical properties and damage mechanism was conducted to reveal the reasons for the differences in the critical energy release rate in the cortical bone structure under different failure modes,which provided a theoretical basis for the measurement of the energy release rate and the accurate fracture simulation.
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Objective:To analyze the performance characteristics of the energy output of defibrillation device at different lifecycle stages of the equipment,and to improve the level of management,so as to ensure the safety and effectiveness of using the device.Methods:A total of 90 defibrillation devices of using 10 types included 861290 and CardioServ(included scrapped devices)during the period of 2015-2022 were retrospectively analyzed.The detected data of energy output of defibrillation device were analyzed as statistical method,and the error of releasing energy was calculated.A total of 36 defibrillation devices that were in the early stages of use(at the first three years of device use)were divided into the first year,the second year and the third year,and the data of energy outputs of devices among three years were compared.The data of the type A and type B defibrillation devices,which were the largest number of devices in the normal stage of use(the middle stage of use),were calibrated according to the energy release in the three years between 2018 and 2000.The difference of releasing energy at the preseted value of 100J between the two types of devices was analyzed.Finally,the errors of energy releases of 8 devices,which energy outputs exceeded the deadline,in the scrap period between 2015 and 2022 were summarized.Results:In the data of three groups of devices in the early stages of use,the differences at the first and second year of device use among 100J,150J and 200J of the energy releases of the preseted values were significant(t=-0.17,-0.17,-0.58,P>0.05).The difference of the measured values between the first and third years of device use was not significant(Z=-0.70,-0.38,-0.86,P>0.05).The results of variance analysis of repeated measurement of the energy releases of the devices in normal stage indicated that the difference of the energy release at 100J preseted point among different types of 41 devices was significant(F=4.40,P<0.05).The energy release of type X defibrillator appeared constantly high,and the relative error increased with the increasing of preseted values.The repeatability of the device was better,and the relationship between preseted energy(x)and release energy(y)conformed to linear relationship(R2=0.9985).In these defibrillation devices that were using,the qualified rate of energy output of>100J preseted point was 97.68%.Conclusion:There is slight difference in the mean value of energy release between different type of defibrillation devices within the qualified range,and the energy release still is a performance indicator that should be highly focused for defibrillation devices.We should combine with the maintenance and repair data of device to conduct in-depth analysis,so as to grasp the operating status of the device,and optimize the strategy of quality control,and ensure the safety of defibrillator in clinical use.
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A fundamentally new direction in the theory and practice of quantum nonlinear phenomena in non-ideal and very close to non-degenerate plasma has been developed, for the first time the existence of a new state of matter-imperfect plasma-quantum plasma condensate, combining the properties of ordinary liquid and ionized plasma, has been theoretically predicted and confirmed. The quantum non-ideality of non-degenerate plasma and the exchange interaction of electrons in it, leading to effective energy release in the plasma process under study, were investigated. The directions of use of this energy have been determined: for heating, lighting, conversion by means of photocells or MHD-movements into electrical, for obtaining energy in the ultraviolet range. Particular attention in the work is paid to one of the most popular applications of quantum non-ideal plasma - for heating, at which its plasma combustion occurs, and the generation of electrical energy based on the use of a quantum plasma-MHD generator with plasma delamination. Detection of this kind of phase state of non-ideal non-degenerate plasma and its use in engineering and technology will create a fundamentally new effective energy system corresponding to the Sixth Technological Order on a global scale. This source of energy is the only environmentally friendly, not destroying or polluting our planet, and its use cleanses our ecosphere. The paper shows that the use of existing energy undermines people's health, reduces their immunity and resistance to coronaviruses. Measures have been proposed to end coronavirus pandemics on Earth. Information is provided on the technical capabilities of the proposed fundamentally new structures - Universal Modules of Industrial Disintegrators / Activators, which allow to implement grandiose, payback state projects on the basis of the developed nanotechnologies, representing the work of tens of millions of people
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O objetivo deste estudo foi analisar o desempenho supra-máximo no nado crawl (vmax) pelas relações entre energia anaeróbia (Eanaer), potência muscular (Po) e propulsiva (Pu), eficiência mecânica (emec) e propulsiva (ep), economia e força de arrasto (Fr). Onze competidores submeteram-se à avaliação de Fr pelo método de Perturbação da Velocidade e à estimativa da ep, pelas relações entre Fr e a ação do hidrofólio. Eanaer foi quantificada pelo equivalente energético do lactato e da fosfocreatina. Correlações de vmax com Eanaer (0,71), economia (0,65), Fr (0,68), Pu (0,79) e Po (0,69) sugerem que força, potência e disponibilidade de energia sustentam o desempenho em vmax. Contudo, ao restringir Eanaer em vmax, apenas a economia acomoda-se a esta condição (-0,95), enquanto que emec torna-se determinante para Fr (0,97), Pu (0,90) e Po (0,98). Conclui-se que a taxa de trabalho é decisiva no desempenho supramáximo, e que Eanaer subsidia sua produção, mas quando restrita, emec e economia interagem-se como fatores fundamentais para manter a taxa de trabalho no patamar demandado por esta condição de nado.
The purpose of this study was to analyze crawl performance at supramaximal intensity (vmax) from relationships between anaerobic energy (Eanaer), mechanical and propulsive power (Po, Pu), mechanical and propulsive efficiency (emec, ep), and drag force (Fr). Eleven experience swimmers were undergone to the measurement of Fr from the method of Velocity Perturbation, and to estimative the ep from Fr relationships to hydrofoil action. Eanaer was estimated from lactate and phosphocreatine energy equivalents. Correlations of vmax to Eanaer (0,72), economy (0,65), Fr (0,68), Pu (0,79), and Po (0,69) suggest a trend to force, power and energy release to determine performance at vmax. Once Eanaer became constrained, only economy was able to accommodated to these context (-0,95), whereas emec improve their influence on Fr (0,97), Pu (0,90), and Po (0,98). In conclusion, work rate is the main parameter to ensure supramaximal performance, and Eanaer is the major factor in power availability, but when it is constrained, emec and economy interactions plays a fundamental role to maintain the level of work rate production enough to reach supramaximal swim requirements.