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This review covers methods and recent developments of the theoretical study of domain structures in ultrathin ferroelectric films. The review begins with an introduction to some basic concepts and theories (e.g., polarization and its modern theory, ferroelectric phase transition, domain formation, and finite size effects, etc.) that are relevant to the study of domain structures in ultrathin ferroelectric films. Basic techniques and recent progress of a variety of important approaches for domain structure simulation, including first-principles calculation, molecular dynamics, Monte Carlo simulation, effective Hamiltonian approach and phase field modeling, as well as multiscale simulation are then elaborated. For each approach, its important features and relative merits over other approaches for modeling domain structures in ultrathin ferroelectric films are discussed. Finally, we review recent theoretical studies on some important issues of domain structures in ultrathin ferroelectric films, with an emphasis on the effects of interfacial electrostatics, boundary conditions and external loads. 相似文献
994.
Cu electrodeposition was performed on a cylindrical AZ80 substrate with a U-shaped surface. A uniform deposition of Cu was achieved on an AZ80 electrode via galvanostatic etching, followed by Cu electrodeposition in an eco-friendly alkaline Cu plating bath. Improper wetting and lower rotational speeds of the AZ80 electrode resulted in an uneven Cu deposition at the inner upper site of the U-shaped surface during the Cu electroplating process. This wetting effect could be deduced from the variation in the anodic potential during the galvanostatic etching. The corrosion resistance of the Cu-deposited AZ80 electrode can be considerably improved after Ni electroplating. 相似文献
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996.
Sheng-Qiang Gao Li-Dong Huang Rui-Jie Dai Dong-Dong Chen Wei-Jian Hu Yun-Feng Shan 《International journal of clinical and experimental pathology》2015,8(11):14779-14785
Peripheral blood-derived inflammation-based scores such as the neutrophil-lymphocyte ratio (NLR) have recently been proposed as prognostic markers in ulcerative colitis. In some previous serological markers are commonly used to detect the severity of the Crohn’s disease (CD), but their sensitivity and specificity are relatively low. So we want to use simple indicators which are easy to obtain to predict disease severity. Now, we investigated and compared the capacity of NLR and other inflammatory markers in detecting CD activity and differentiating CD patients from healthy controls. These CD patients had not received corticosteroid or immunosuppressive drugs within a defined period of time. Data from our hospital between 2010 and 2012 was used. Neutrophil-lymphocyte ratio (NLR), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cells (WBC), platelet count and albumin were measured in 44 patients with active CD, 66 patients with inactive CD, and 55 healthy blood donors. Disease activity was assessed by the Crohn’s Disease Activity Index. In the active CD group, NLR values were found to be elevated compared to inactive CD patients and controls (6.00±7.38, 5.53±6.18 and 1.84±0.85, respectively), but statistical difference was not found between active and inactive CD groups. The overall accuracy of NLR (cutoff: 2.13 fl), CRP (cutoff: 10.5 mg/dl), ESR (cutoff: 19.5 mm/hour) and WBC (cutoff: 9.2 × 109/l) in differentiating CD patients from healthy controls was 80.9%, 67.3%, 71% and 60% respectively. NLR values were found to be correlated with WBC and CRP levels. NLR increased in CD patients compared with healthy subjects. NLR had the best accuracy in determination of CD patients and healthy controls. NLR did not show a discriminative value in disease activity. 相似文献
997.
Liang Zhu Xiaohua Shi Huadan Xue Huanwen Wu Ge Chen Hao Sun Yonglan He Zhengyu Jin Zhiyong Liang Zhuoli Zhang 《Medicine》2016,95(5)
This study aimed to determine whether changes in contrast-enhanced computed tomography (CT) parameters could predict postsurgery overall and progression-free survival (PFS) in pancreatic cancer patients. Seventy-nine patients with a final pathological diagnosis of pancreatic adenocarcinoma were included in this study from June 2008 to August 2012. Dynamic contrast-enhanced (DCE) CT of tumors was obtained before curative-intent surgery. Absolute enhancement change (AEC) and relative enhancement change (REC) were evaluated on DCE-CT. PFS and overall survival (OS) were compared based on CT enhancement patterns. The markers of fibrogenic alpha-smooth muscle antigen (α-SMA) and periostin in tumor specimens were evaluated by immunohistochemical staining. The χ2 test was performed to determine whether CT enhancement patterns were associated with α-SMA-periostin expression levels (recorded as positive or negative). Lower REC (<0.9) was associated with shorter PFS (HR 0.51, 95% CI: 0.31–0.89) and OS (HR 0.44, 95% CI: 0.25–0.78). The α-SMA and periostin expression level were negatively correlated with REC (both P = 0). Among several CT enhancement parameters, REC was the best predictor of patient postsurgery survival. Low REC was associated with a short progression-free time and poor survival. The pathological studies suggested that REC might be a reflection of cancer fibrogenic potential. 相似文献
998.
A large number of long noncoding RNAs (lncRNAs) have been found to be implicated in varieties of tumors. However, the contributions of lncRNAs to tumorigenesis in renal clear cell carcinoma (RCCC) remain largely unknown.We performed a genome-wide analysis of lncRNA expression in RCCC and matched nontumor (NT) tissues to identify new targets for further study of renal carcinoma.The genome-wide analysis of lncRNA expression in 3 RCCC and matched NT tissues were conducted using 4 × 180K Agilent lncRNA Chips and 6 lncRNAs were selected and validated by qRT-PCR in 90 RCCC patients. The differentially expressed lncRNAs and mRNAs were recognized through P value and fold-change (FC) filtering. Potential targets associated with RCCC were identified by gene ontology and pathway analyses. Construction of the co-expression network was accomplished using Cytoscape.A total of 3862 lncRNAs and 2935 mRNAs were deregulated in RCCC tissues, compared with paired NT tissues. PCR results showed the expressions of these 6 lncRNAs were consistent with the chips. Moreover, the co-expression network analysis portended 641 nodes and 571 connections between 109 lncRNAs and 532 coding genes. Lastly, NONHSAT123350 could be involved in the pathogenesis of RCCC and its expression level was closely related to disease-free survival (DFS) and overall survival (OS) in patients without distant metastasis.Our results indicated that these abnormal lncRNAs could respond to renal carcinoma progression and NONHSAT123350 may act as a potential target for future treatment of RCCC. 相似文献
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1000.
Thoracoscopic bronchoplasty combined with pulmonary arterial angioplasty can be particularly challenging. In the past, it was often done by using a conventional incision or hybrid video-assisted small incision. In recent years, anecdotal articles have described the application of thoracoscopic bronchoplasty/pulmonary arterial angioplasty. This chapter will describe the details associated with thoracoscopic bronchoplasty/pulmonary arterial angioplasty. 相似文献