Insight into perovskite antiferroelectric phases: Landau theory and phase field study

Understanding the appearance of commensurate and incommensurate modulations in perovskite antiferroelectrics (AFEs) is of great importance for material design and engineering. The dielectric and elastic properties of the AFE domain boundaries are lack of investigation. In this work, a novel Landau theory is proposed to understand the transformation of AFE commensurate and incommensurate phases, by considering the coupling between the oxygen octahedral tilt mode and the polar mode. The derived relationship between the modulation periodicity and temperature is in good agreement with the experimental results. Using the phase field study, we show that the polarization is suppressed at the AFE domain boundaries, contributing to a remnant polarization and local elastic stress field in AFE incommensurate phases

Domain size and charge defects on the polarization switching of antiferroelectric domains

The switching behavior of antiferroelectric domain structures under the applied electric field is not fully understood. In this work, by using the phase field simulation, we have studied the polarization switching property of antiferroelectric domains. Our results indicate that the ferroelectric domains nucleate preferably at the boundaries of the antiferroelectric domains, and antiferroelectrics with larger initial domain sizes possess a higher coercive electric field as demonstrated by hysteresis loops. Moreover, we introduced charge defects into the sample and numerically investigated their influence. It is also shown that charge defects can induce local ferroelectric domains, which could suppress the saturation polarization and narrow the enclosed area of the hysteresis loop. Our results give insights into understanding antiferroelectric phase transformation and optimizing the energy storage property in experiments

Research on the Effect of Light and Heat Sensing along Meridian of Chinese Medicine

INTRODUCTION: Photonics refers to the technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. Photonic technology in the meridian and acupoints research has shown the unique advantages, by which the microcosmic material basis and macroscopic phenomena research can be integrated to interpret the occurrence of propagated sensation along meridian (PSM) and its underlying mechanism. This study seeks to investigate light and heat sensing action along meridian.METHODS: From the modern research of meridian point of view, PSM is the break point to research the essentiality of meridian. The bio-photonic feature of meridian is the most promising research direction to investigate the PSM phenomena for its contribution to prove the existence of meridian objectively and spontaneously. Therefore, the bio-photonic features of meridian under physiological, pathological, therapeutic, and mechanical conditions were analyzed. Firstly, the four aspects of light sensing action were discussed, i.e. light sensing effect along meridian, blocking effect, laser induced effect and underlying mechanism of light sensing action along meridian. Secondly, the four items of heat sensing action were discussed as well, i.e. thermo-effects, heat perception ability, laser induced heat effect, underlying mechanism on heat sensing effect along meridian.RESULTS: The authors point out that photonic technology, e.g. ultra-weak luminescence, photonic imaging, infrared imaging and infrared spectrum analysis, biological photons detection and laser Doppler application, can achieve purposes of in vivo, dynamic, multiple comparable studies. Thereby, the effect of light and heat sensing along meridian can be detected and illustrated by the use of natural science. The effect of light sensing and heat sensing along meridians with the help of advantages of photonics is expected to interpret and quantify the meridian doctrine, to provide an important experimental basis for meridians and acupoint properties of light and heat, to find a kind of non-invasive diagnostic technique, and to promote the integration and development of meridians and modern medicine.CONCLUSION: Light and heat information can be investigated to analyze the relationship between zang-fu organs and meridians, and the functional characteristics of the meridian. Hence, the effect of light and heat sensing along meridian is the break point of the research of photonics in meridian, which is beneficial to further study the meridian optics

Beyond Gisin's Theorem and its Applications: Violation of Local Realism by Two-Party Einstein-Podolsky-Rosen Steering

We demonstrate here that for a given mixed multi-qubit state if there are at least two observers for whom mutual Einstein-Podolsky-Rosen steering is possible, i.e. each observer is able to steer the other qubits into two different pure states by spontaneous collapses due to von Neumann type measurements on his/her qubit, then nonexistence of local realistic models is fully equivalent to quantum entanglement (this is not so without this condition). This result leads to an enhanced version of Gisin's theorem (originally: all pure entangled states violate local realism). Local realism is violated by all mixed states with the above steering property. The new class of states allows one e.g. to perform three party secret sharing with just pairs of entangled qubits, instead of three qubit entanglements (which are currently available with low fidelity). This significantly increases the feasibility of having high performance versions of such protocols. Finally, we discuss some possible applications.Comment: 9 pages, 1 figur

Diagnosis and treatment of pericallosal artery aneurysms

Objective Pericallosal artery aneurysms are not common clinically. The microsurgery and endovascular therapy are surgically challenging operations. The objective of the study is to summarize their clinical symptoms and optimal treatment strategies of pericallosal artery aneurysms. Methods Nine cases of pericallosal artery aneurysms detected by digital subtraction angiography (DSA) were reviewed. The clinical manifestation, brain imaging characteristics, and optimal treatment methods were summarized. Results Patients with spontaneous aneurysm had good clinical outcomes after endovascular coiling or microsurgical clipping treatment. There were no any neurological function deficits in five patients. One patient suffered from permanent neurological function deficits. Patients with traumatic aneurysm pericallosal had relatively poor outcomes, including two patients showing disturbed consciousness and the paralysis of the lower limbs with slow recovery, and one patient was dead after the surgery. Conclusion Spontaneous subarachnoid hemorrhage and interhemispheric fissure hematoma suggest spontaneously pericallosal aneurysm, while traumatic corpus callosum hematoma as well the accompanying embryo of intraventricular hemorrhage suggest traumatic pericallosal aneurysm. Endovascular embolization is the primary surgical treatment for pericallosal aneurysm, while patients with pericallosal aneurysm are not suitable for surgical treatment. Microsurgical clipping treatment may be a choice. However, both of these treatment strategies have high risk

Seismic loss assessment for buildings with multiple LOD BIM data

Earthquake-induced economic loss of buildings is a fundamental concern for earthquake-resilient cities. The FEMA P-58 method is a state-of-the-art seismic loss assessment method for buildings. Nevertheless, because the FEMA P-58 method is a refined component-level loss assessment method, it requires highly detailed data as the input. Consequently, the knowledge of building details will affect the seismic loss assessment. In this study, a seismic loss assessment approach for buildings combining building information modeling (BIM) with the FEMA P-58 method is proposed. The detailed building data are automatically obtained from the building information model in which the building components may have different levels of development (LODs). The determination of component type and the development of the component vulnerability function when the information is incomplete are proposed. Finally, to demonstrate the rationality of the proposed method, an office building that is available online is selected, and the seismic loss assessments with multi-LOD BIM data are performed as case studies. The results show that, on the one hand, even if the available building information is limited, the proposed method can still produce an acceptable loss assessmenton the other hand, given more information, the accuracy of the assessment can be improved and the uncertainty can be reduced using the proposed method.The study is financial supported by the National Natural Science Foundation of China (No. 51578320)