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It is known that high-index perovskite ferroelectric thin films exhibit giant permittivity, piezoelectric response, and a particular switching behavior. However, the fine domain configuration in high-index ferroelectric films is not yet clarified, which triggers difficulties to further modulate their electric properties. In this work, we focus on the tetragonal PbTiO3 thin films with thicknesses of 20, 40, 55, and 70 nm deposited on a [101]-oriented KTaO3 substrate. By using piezoresponse force microscopy and state-of-the-art scanning transmission electron microscopy, the stripe a/c domains with alternately wide c and narrow a domains are observed in all these PbTiO3 films. The periodic stripe a/c domains with {101} domain walls extend along the in-plane [ 11 1 ¯ ] or [ 1 1 ¯ 1 ¯ ] direction, which almost completely relaxes the misfit strain between the PbTiO3 films and the KTaO3 substrate. The domain width decreases as the film thickness is reduced following the square root dependence. This results in an increase of ferroelastic a/c domain walls and promotes the enhancement of the piezoresponse amplitude for the thinner PbTiO3 films. In addition, the piezoresponse amplitude of a 20 nm PbTiO3 film is comparable to that of a 40 nm PbTiO3 film, which indicates that the piezoelectric response of ferroelectric films may saturate at a certain film thickness and scarcely increase even after the film thickness reduces further. These results clarify the domain configurations of [101]-oriented PbTiO3 thin films and provide useful information for understanding the relationship between microstructures and piezoelectric properties in ferroelectric films. [ABSTRACT FROM AUTHOR]

Topological structures in ferroelectric materials play a crucial role in the potential applications of high-density memories and are currently the subject of intensive interest. Interfaces with local symmetry breaking have garnered wide attention in designing the topological domains in ferroelectric films by regulating the different boundary conditions. Here, we present multiple topological polar nanodomains near the heterointerfaces in the trilayered systems of BiFeO3/GdScO3/BiFeO3 grown on [110]-oriented TbScO3 substrates. The formation and stabilization of these topological polar states depend on the electrical and mechanical boundary conditions of the BiFeO3 layers. Aberration-corrected transmission electron microscopy observation reveals that the topological polar nanodomains, including nano-scale vortices and flux-closures at the termination of 109° domain walls and the semi-vortices at the end of 180° domain walls, are stabilized in the BiFeO3 layers confined by two orthorhombic structures. Furthermore, the formation of flux-closures near the BiFeO3/GdScO3 interface is influenced by the domain structures in the adjacent BiFeO3 layers, which is preferred by the 180° domain patterns rather than the 109° domain patterns. This work provides further understanding into the influences of boundary conditions on topological polar configurations and would offer guidance for designing novel topological states that enable the development of high-density memory devices. [ABSTRACT FROM AUTHOR]

Domain walls in ferroelectric materials attract great interest since they can possess fascinating functionalities. Therefore, it is very important to modulate domain structures. Our recent experiments showed that oxygen vacancy plates could induce charged domain walls with different types. However, the detailed transition behavior between different charged domain walls was not explored. In this work, systematical phase field simulations were performed to reveal the evolution of domain structures with the size and charge density of the oxygen vacancy plate. These results could provide a route to build complex patterns of charged domain walls. [ABSTRACT FROM AUTHOR]

Ranking fuzzy numbers(FNs) was a critical issue in fuzzy computing field. Generally, triangular FNs, trapezoidal FNs, and even interval-valued FNs(IVFNs) were often expressed in ranking. However, ranking intuitionistic FNs(IFNs) were less mentioned due to the complicated components in membership functions. Herein, we will develop fuzzy binary relation that is an extended fuzzy preference relation(EFPR) to express the preference degree of two IFNs, and then the relation is improved to be a relative preference relation(RPR) used to rank a set of IFNs. Since EFPR on IFNs is a total ordering relation, RPR will be also a total ordering relation. Based on belonging and non-belonging components of membership functions in IFNs, using EFPR being also fuzzy preference relation(FPR) is suitable to compare FNs on pairwise, but time complexity on fuzzy operation of comparison computing is complicated. Hence, RPR is developed to avoid comparing on pairwise. Through yielding RPR values for a set of IFNs, IFNs are effectively and efficiently ranked to utilize related decision-making problems. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to assess the application value of distal femur 90° locking plate fixation for supracondylar femoral fractures (SFF) in children. PATIENTS AND METHODS: A total of 100 SFF children with or without diabetes who were enrolled in our hospital from January 2018 to January 2020 were randomized into a control group and a study group by the random number table method. The study group received distal femur locking plate fixation, and the control group adopted Kirschner wire (K wire) internal fixation. The primary outcomes of the two groups of children and the secondary outcomes of the diabetic patients were compared. RESULTS: The fracture union rate of the study group was significantly higher than that of the control group at 12 weeks, 16 weeks, 20 weeks and 24 weeks after the operation (p<0.05), while the rate showed no significant difference between the two groups at 28 weeks after the operation (p>0.05). The two groups showed similar operation time, intraoperative blood loss, intraoperative fluoroscopy time, and hospital stay (p>0.05). The study group yielded a more favorable outcome with regard to the Harris-Hip-Score (HHS) scores, HHS excellent- and-good rate, and Flynn scores satisfaction rate than the control group (p<0.001 or 0.05). The intracavitary pressure of the knee joint of the two groups presented a gradual decline with time, with remarkably lower results in the study group compared with the control group at 8 weeks and 16 weeks after the surgery (p<0.05), and differences at 24 weeks after the surgery did not come up to the statistical standard (p>0.05). Patients experienced fewer postoperative complications after locking plate fixation, as compared to those who received K wire treatment (p<0.05). Compared with the control group, the fracture union rate of diabetic children in the study group was significantly higher at 12 weeks, 16 weeks, and 20 weeks after surgery, respectively (p<0.05), while there was no significant difference between the two groups at 24 weeks and 28 weeks (p>0.05). CONCLUSIONS: The distal femur 90° locking plate fixation for diabetic children with SFF obviates the need for plate shaping and ensures firm fixation, with biomechanical design, promising efficacy, and few complications. The distal femur 90° locking plate fixation has better efficacy for children with diabetes. It shows great potential as the treatment of choice for diabetic children with SFF. [ABSTRACT FROM AUTHOR]

The mathematical model of infectious disease is a typical problem in mathematical modeling, and the common infectious disease models include the susceptible-infected (SI) model, the susceptible-infected-recovered model (SIR), the susceptible-infected-recovered-susceptible model (SIRS) and the susceptible-exposed-infected-recovered (SEIR) model. These models can be used to predict the impact of regional return to work after the epidemic. In this paper, we use the SEIR model to solve the dynamic medicine demand information in humanitarian relief phase. A multistage mixed integer programming model for the humanitarian logistics and transport resource is proposed. The objective functions of the model include delay cost and minimum running time in the time-space network. The model describes that how to distribute and deliver medicine resources from supply locations to demand locations with an efficient and lower-cost way through a transportation network. The linear programming problem is solved by the proposed Benders decomposition algorithm. Finally, we use two cases to calculate model and algorithm. The results of the case prove the validity of the model and algorithm. [ABSTRACT FROM AUTHOR]

Tobacco leaf quality matter its value but is easily influenced by environmental factors, such as antibiotics, which reside in soil by utilization of manure. Experiments were conducted by adding ciprofloxacin (CIP) and oxytetracycline (OTC) compounds to hydroponic tobacco seedlings with three varieties, Honghua Dajinyuan (HD), Yunyan87 (Y87) and K326, and their growth was observed. Results showed that concentration of chlorophyll a decreased by 83.33%, 88.36% and 87.59% in HD, Y87 and K326 at 60 mg L-1 CIP+60 mg L-1 OTC treatment. Aboveground fresh weight decreased from 1.24 g to 0.2 g in HD, from 0.53 g to 0.25 g in Y87 and from 0.83 g to 0.38 g in K326 at 60 mg L-1 CIP+60 mg L-1 OTC treatment. With increasing antibiotic concentrations, CIP was accumulated from 1.33 to 1.56 µg g-1 in Y87 and from 4.66 to 7.98 µg g-1 in K326, and OTC was accumulated from 0.54 to 0.84 µg g-1 in Y87 and from 3.30 to 5.53 µg g-1 in HD. With increasing antibiotic concentrations, chlorophyll and carotenoid contents, root activity, enzyme activity and fresh weight decreased significantly, and more antibiotics accumulated from 0.54-7.98 µg g-1 differently in all three varieties of tobacco. Comparing experiment results it suggests that chlorophyll and carotenoid contents and aboveground fresh weight decreased less in Y87, and it accumulated less antibiotics as well. Y87 could grow better and accumulate less antibiotic compared with the other two varieties. [ABSTRACT FROM AUTHOR]