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BaTiO3 has advantages of high permittivity, low dielectric loss, low cost and environment friendly. However, due to the nonlinear dielectric behavior occurred around the phase transition temperature of BaTiO3 ceramic, its availability in the field of temperature-stable capacitor is limited. To modify the dielectric-temperature properties of BaTiO3, a series of BaTi1-xCexO3 (x=0-0.20) ceramics was synthesized by solid-state reaction method. Ce dopant was introduced into the B-site (Ti-site) of BaTiO3. The effects of Ce dopant on the phase evolution, defect state, microstructure and dielectric properties were investigated. The modifying mechanism was also discussed with the help of first-principles calculation method. In all ceramic samples, it is revealed that Ce element completely enters the B-site of BaTiO3 in the form of Ce4+ ion. With the increase of Ce doping concentration, the room temperature structure of BaTi1-xCexO3 ceramics transforms from tetragonal/pseudo-cubic structure into orthorhombic/tetragonal structure, then into pseudo-cubic structure. Owing to the radius difference between Ce4+ and Ti4+ ions, Ce doping will lead to the rising of lattice parameters, accompanied by the appearance of local distortion and the decrease of long-range ferroelectric order, the variation of band structure, density of states and charge density configuration, as well as the generation of Ba and Ti vacancies. Compared with pure BaTiO3 ceramic, the average grain size of Ce-doped ceramics decreases first and then increases with the increase of Ce content, while the relative density of ceramics increases gradually. The peak dielectric constant of BaTi1-xCexO3 ceramic increases first and then decreases as the Ce concentration increasing. The corresponding temperature is slowly reduced from 122 ℃ to 112 ℃ in the x value range of 0-0.08, then rapidly declines to -3 ℃ in the x value range of 0.08-0.20. BaTi1-xCexO3 ceramics with x≥0.06 have the dielectric behavior of diffused phase transition (DPT). And the x=0.20 ceramic exhibits the typical characteristic of relaxor ferroelectric, with the room temperature dielectric constant of 3258.38, and the |Δεr/εr25 ℃|≤22% temperature range of -60-87 ℃, which matches the requirement of EIA X5S standard. Therefore, it can be concluded that B-site Ce doping will effectively enhance the permittivity stability of BaTiO3 in a variable temperature environment. This will provide some new ideas to develop dielectric materials with stable dielectric properties in wide temperature range.

Owing to the feature of ultrahigh power density, the dielectric capacitors play an increasingly important role in the field of industrial production, basic scientific research, aerospace, and military industry in recent years. However, the relatively low energy storage density of the dielectric capacitors generally leads to their big sizes, which is difficult to meet the miniaturization requirements of future devices. Polymer-ceramic nanocomposites can combine high permittivity of the ceramic fillers and the excellent breakdown strength of the polymer matrix, thus achieving excellent energy storage performance. At present, developing the polymer-ceramic nanocomposites with high energy storage density is the key to realize the miniaturization goal of dielectric capacitors in the future. The current research progress of polymer-ceramic nanocomposites for energy storage capacitor applications from three perspectives was systematically summarized, including regulation of the nanofillers, optimization of the interfaces, and design of the multilayer composite structure. Notably, the influences of the dimension, size, species, hierarchical structure of the nanofillers, interface optimization methods such as surface modification and core-shell structure construction, as well as multilayer structure design such as sandwich structure and gradient structure on the permittivity, breakdown strength and the energy storage density of the nanocomposites were introduced in detail. Meanwhile, the structure-activity relationships between the microstructure of nanocomposites and their energy storage properties were further analyzed and discussed. Finally, based on the challenges and shortcomings of the current research, the important development directions of this field in the future were proposed, including selecting the new 2D nanofillers, enhancing the energy storage efficiency, employing multimode combined optimization strategy, and constructing the corresponding dielectric capacitors.

Background: Clear and complete reporting of the components of complex interventions is required in clinical trials to ensure that research can be reliably replicated and successfully translated into clinical practice. Movement-based mind-body exercises, such as Tai Chi, qigong, and Yoga (TQY), are considered complex interventions and recommended for individuals with osteoarthritis in the latest guidelines of the American College of Rheumatology. This review analyzes the intervention reporting of randomized controlled trials of TQY to guide the implementation in osteoarthritis exercise programs. Methods: We searched PubMed, Cochrane Central Register of Controlled Trials, and EMBASE for TQY exercise trials in osteoarthritis between 2000 and 2020. Pairs of researchers independently screened the records, extracted study characteristics, and assessed 19 items on the Consensus on Exercise Reporting Template (CERT) checklist. For each of these items, the numbers of studies that clearly reported the item were calculated. We then identified the items in the studies that are key to delivering home-based exercises for further analysis. Results: We included 27 publications reporting 22 TQY interventions in the analysis. None of the studies reported sufficient details on all the 19 CERT items. The median completeness of reporting score was 11 and ranged from 6 to 15 of 19. The most frequently incompletely reported items (number reporting and percentage of studies) were "starting level rule" (n = 1, 5%) and "progression rule" (n = 1, 5%). Other incompletely reported items included "fidelity or adherence (planned)" (n = 9, 41%), "motivations" (n = 9, 41%), and "progression description" (n = 5, 23%). Conclusions: The content analysis highlights motivational strategies for long-term adherence to home-based exercises, which may help clinicians develop interventions for their patients. Details of TQY exercises interventions for osteoarthritis are incompletely reported in the included studies. The study suggests that improvements in content reporting are especially needed on items related to exercise intensity and program progression decisions, and motivational strategies in future implementation.

Dissemination research is the study of distributing information and intervention materials to a specific clinical practice or public health audience. Acupuncture, a healthcare practice involving the stimulation of certain body points, often with thin needles, is considered an evidence-based treatment for low back pain (LBP), but is underutilized in the United States. Body: We will use the example of acupuncture for LBP to identify opportunities to leverage dissemination research to increase utilization of acupuncture. Deficits in the awareness or knowledge of acupuncture may limit its adoption by patients and other stakeholders. Thus, we summarize methods to gather data on stakeholder awareness and knowledge of acupuncture for LBP, i.e., audience research. Engaging multiple stakeholder audiences (e.g., health system leaders, primary care providers, patients), is needed to generate knowledge on promising dissemination strategies for each audience. Audience segmentation is important for identifying population subgroups for whom adoption of acupuncture may require a more intensive or tailored dissemination strategy. To illustrate potential audience 'segments', our research discussion focused on developing dissemination strategies by age (i.e., older adults - those age 65 years or older, and younger adults - those under age 65 ). This decision was prompted by Medicare's recent policy covering acupuncture for chronic LBP. We leverage current knowledge of barriers and facilitators of acupuncture use to discuss how further tailoring of dissemination strategies might optimize adoption of acupuncture in both groups of adults. Experimental study designs could then be used to compare the effectiveness of such strategies to increase awareness, knowledge, or adoption of acupuncture. Conclusions: Conducting dissemination research may improve awareness and knowledge of acupuncture, and ultimately the adoption of acupuncture in biomedical settings. We anticipate that the concepts highlighted in this manuscript will also be helpful for those disseminating information about other complementary and integrative health approaches.