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The generally nonpolar SrTiO3 has attracted more attention recently because of its possibly induced novel polar states and related paraelectric-ferroelectric phase transitions. By using controlled pulsed laser deposition, high-quality, ultrathin, and strained SrTiO3 layers were obtained. Here, transmission electron microscopy and theoretical simulations have unveiled highly polar states in SrTiO3 films even down to one unit cell at room temperature, which were stabilized in the PbTiO3/SrTiO3/PbTiO3 sandwich structures by in-plane tensile strain and interfacial coupling, as evidenced by large tetragonality (â¼1.05), notable polar ion displacement (0.019 nm), and thus ultrahigh spontaneous polarization (up to â¼50 µC/cm2). These values are nearly comparable to those of the strong ferroelectrics as the PbZrxTi1-xO3 family. Our findings provide an effective and practical approach for integrating large strain states into oxide films and inducing polarization in nonpolar materials, which may broaden the functionality of nonpolar oxides and pave the way for the discovery of new electronic materials.
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Antiferroelectrics characterized by voltage-driven reversible transitions between antiparallel and parallel polarity are promising for cutting-edge electronic and electrical power applications. Wide-ranging explorations revealing the macroscopic performances and microstructural characteristics of typical antiferroelectric systems have been conducted. However, the underlying mechanism has not yet been fully unraveled, which depends largely on the atomistic processes. Herein, based on atomic-resolution transmission electron microscopy, the deterministic phase transition pathway along with the underlying lattice-by-lattice details in lead zirconate thin films was elucidated. Specifically, we identified a new type of ferrielectric-like dipole configuration with both angular and amplitude modulations, which plays the role of a precursor for a subsequent antiferroelectric to ferroelectric transformation. With the participation of the ferrielectric-like phase, the phase transition pathways driven by the phase boundary have been revealed. We provide new insights into the consecutive phase transformation in low-dimensional lead zirconate, which thus would promote potential antiferroelectric-based multifunctional devices.
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BACKGROUND: Managing increasing numbers of diabetic patients is placing increasing pressure on healthcare providers, especially general practitioners, who usually serve in multiple roles. This situation has caused generally poor results in terms of diabetes management. However, community nurses in some countries have successfully and effectively controlled chronic diseases among their patients. Therefore, the effects of nurse-led management is worth further exploration in order to better understand and promote this mode of care. PURPOSE: To explore the effects of community-nurse-led team management on diabetes patients. METHODS: An experimental research design was adopted. Patients with type 2 diabetes were recruited from two community health centers (the first for the intervention group, the second for the control group) in Wuhou District, Chengdu City, China. The intervention group received nurse-led team management care for 2 years, while the control group received standard care. The evaluations were conducted before the intervention and at 6, 12, and 24 months into the intervention. Outcomes included glycosylated hemoglobin (HbA1c) level, body mass index, waist circumference, visual acuity, ankle brachial index, kidney function index, urinary protein level, and electrocardiogram. RESULTS: The 179 participants included 88 in the intervention group and 91 in the control group. After the intervention, HbA1c level, ankle brachial index, and waist circumference were all significantly better in the intervention group than in the control group (F = 28.894, p < .01; F = 4.065, p < .01; F = 5.540, p < .01). The other outcome variables remained statistically similar between both groups throughout the study period. CONCLUSIONS: Community nurse-led team management is an effective mode of care in terms of controlling blood glucose control and preventing diabetes-related complications.
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Servicios de Salud Comunitaria , Diabetes Mellitus Tipo 2/terapia , Enfermeras y Enfermeros , Grupo de Atención al Paciente , Adulto , Anciano , Diabetes Mellitus Tipo 2/sangre , Femenino , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Based on data obtained from 572 branches of 45 Chinese fir trees in Jiangle Forest Farm, Fujian Province, southeast China, prediction models for branch, foliage biomass and total branch and foliage biomass of individual tree were developed by linear mixed effects (LME) method, and tested by independent samples. The results showed that the LME models provided better performance than the multiple linear regression models for the branch, foliage and total biomass prediction of Chinese fir plantation. The LME models with different combinations of the random effects parameters had different fitting precisions. The LME models including variance structures could effectively remove the heteroscedasticity in the data and improved the precision. The LME model with the exponential function as the variance structure had better fitting precisions for the total biomass and foliage biomass models, and that with the constant plus power function as the variance structure had better performance for the branch biomass model. Model validation confirmed that the LME models with the random effects and heteroscedasticity structure could significantly improve the precision of prediction, compared to the multiple linear regression models.
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Cunninghamia/crecimiento & desarrollo , Bosques , Modelos Lineales , Biomasa , China , Árboles/crecimiento & desarrolloRESUMEN
PURPOSE: To explore associations of CYP2E1 and NAT2 polymorphisms with lung cancer susceptibility among Mongolian and Han populations in the Inner Mongolian region. MATERIALS AND METHODS: CYP2E1 and NAT2 polymorphisms were detected by PCR-RFLP in 930 lung cancer patients and 1000 controls. RESULTS: (1) Disequilibrium of the distribution of NAT2 polymorphism was found in lung cancer patients among Han and Mongolian populations (p=0.031). (2) Lung cancer risk was higher in individuals with c1, D allele of CYP2E1 RsaI/PstI, DraI polymorphisms and slow acetylation of NAT2 (c1 compared with c2, OR=1.382, 95%CI: 1.178- 1.587, p=0.003; D compared with C, OR=1.241, 95%CI: 1.053-1.419, P<0.001; slow acetylation compared with rapid acetylation, OR=1.359, 95%CI:1.042-1.768, p=0.056) (3) Compared with c2/c2 and rapid acetylation, c1/c1 together with slow acetylation synergetically increased risk of lung cancer 2.83 fold. (4) Smokers with CYP2E1 c1/c1, DD, and NAT2 slow acetylation have 2.365, 1.916, 1.841 fold lung cancer risk than others with c2/c2, CC and NAT2 rapid acetylation, respectively. (5) Han smokers with NAT2 slow acetylation have 1.974 fold lung cancer risk than others with rapid acetylation. CONCLUSIONS: Disequilibrium distribution of NAT2 polymorphism was found in lung cancer patients among Han and Mongolian populations. Besides, Han smokers with NAT2 slow acetylation may have higher lung cancer risk compared with rapid acetylation couterparts. CYP2E1 c1/ c1, DD and NAT2 slow acetylation, especially combined with smoking, contributes to the development of lung cancer. CYP2E1 c1/c1 or DD genotype and NAT2 slow acetylation have strong synergistic action in increasing lung cancer risk.