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To determine the differences in supraclavicular lymph node metastasis between esophageal cancer (EC) and nasopharyngeal cancer (NPC) and explore the feasibility of differential supraclavicular clinical target volume (CTV) contouring between these two diseases based on the involvement of different fascial spaces.One hundred patients with supraclavicular nodes positive for EC or NPC were enrolled, and their pre-treatment images were reviewed. The distribution patterns of nodes between the two diseases were compared in the context of node levels defined by the 2017 Japanese Esophageal Society and 2013 International Consensus on Cervical Lymph Node Level Classification. Grouping supraclavicular nodes based on sub-compartments formed by the cervical fascia was discussed, and the feasibility of differential CTV contouring based on the differences in the involvement of these sub-compartments between EC and NPC was explored.The 2013 Consensus on cervical node levels and 2017 Japanese Esophageal Society node station could not practically guide supraclavicular CTV contouring. We divided the supraclavicular space into six sub-compartments: the para-esophageal space (PES), carotid sheath space (CSS), sub-thyroid pre-trachea space (STPTS), pre-vascular space (PVS), and vascular lateral space (VLS) I and II. EC mainly spread to the PES, STPTS, CSS, and VLS I, whereas NPC tended to spread to the CSS, VLS I, and VLS II. These combinations of sub-compartments may help constitute the supraclavicular CTVs for EC and NPC.The fascia anatomy-based sub-compartments sufficiently distinguished metastasis to the supraclavicular space between EC and NPC, thus facilitating differential CTV contouring between these two diseases.

Highlights • MRI radiomics is promising for NAC early response prediction in NPC patients. • Predictive performance could be improved by the optimized strategy. • The model could help with NPC individualized treatment., Background and purpose Neoadjuvant Chemotherapy (NAC) followed by concurrent chemoradiotherapy (CCRT) is promising in improving the survival rate for advanced nasopharyngeal carcinoma (NPC) patients relative to CCRT alone. However, not all patients respond well to NAC. Therefore, we aimed to develop and evaluate a modified radiomics model for the NAC response prognosis in NPC patients. Methods A total of 165 patients with biopsy-proven locally advanced NPC were retrospectively selected from the database of our hospital. 85 out of them were for training and cross-validation, while the other 80 patients were for independent testing. All patients were treated with NAC and underwent MRI inspection, including T1-weighted (T1), T2-weighted (T2), and contrast-enhanced T1-weighted (T1-cs) sequences before and after two cycles of NAC. We classified the patients into the response or non-response groups by the Response Evaluation Criteria in Solid Tumors 1.1 (RECIST 1.1). Radiomics features were extracted from the primary and lymph node gross tumor volume in each sequence. To further improve the predictive performance, the permutation of multiple combinations of extraction parameters has first ever been investigated in the NAC prognosis for NPC patients. The model was constructed by logistic regression and cross-validated by bootstrapping with a resampling number of 1000. Independent testing was also implemented. In addition, we also applied an imbalance-adjusted bootstrap strategy to decrease the bias of small samples. Results For the cross-validation cohort, the resultant AUC, sensitivity, and specificity in terms of 95% confidence interval were 0.948 ± 0.004, 0.849 ± 0.005, and 0.840 ± 0.010. For the independent testing cohort, the model reached an AUC of 0.925, a sensitivity of 0.821, and a specificity of 0.792. There was a significant difference in the estimated radiomics score between the response and non-response groups (P

ObjectivesIt remains controversial whether sarcopenia has any significant impact on the efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) or immune checkpoint inhibitors (ICIs) in patients with advanced non-small cell lung cancer (NSCLC). Therefore, in this study, we aimed to assess the association between sarcopenia and clinical outcomes in patients with advanced NSCLC receiving EGFR-TKIs or ICIs as a first-line therapy.MethodsWe retrospectively enrolled 131 patients with advanced NSCLC treated with first-line EGFR-TKIs or ICIs between 1 March 2019 and 31 March 2021. To estimate sarcopenia, we calculated skeletal muscle index (SMI) as the ratio of skeletal muscle area (cm2) to height squared (m2). Associations between sarcopenia and overall survival (OS) and progression-free survival (PFS) were evaluated using the Kaplan–Meier method and log-rank tests, respectively. A Cox proportional hazards regression model was used to assess the factors associated with OS and PFS. The Student’s t-test or Mann–Whitney U test was used to compare the SMI between patients with or without objective response and disease control. The chi-squared test was used to compare adverse events (AEs) between patients with and without sarcopenia.ResultsAmong the 131 patients, 35 (26.7%) were diagnosed with sarcopenia. Sarcopenia was an independent predictor of poor OS and PFS (p < 0.05) overall and in the EGFR-TKI- and ICI-treated cohorts. Among all patients, those with sarcopenia showed significantly shorter OS and PFS than those without sarcopenia (median OS and PFS: 13.0 vs. 26.0 months and 6.4 vs. 15.1 months; both p < 0.001). These associations were consistent across the subtypes of most clinical characteristics. Statistically significant differences between the objective response (OR) and non-OR groups were also observed in the mean SMI (OR group, 43.89 ± 7.55 vs. non-OR group, 38.84 ± 7.11 cm2/m2; p < 0.001). In addition, we observed similar results with disease control (DC) and non-DC groups (DC group, 42.46 ± 7.64 vs. non-DCR group, 33.74 ± 4.31 cm2/m2; p < 0.001). The AEs did not differ significantly between the sarcopenia and non-sarcopenia groups.ConclusionSarcopenia before treatment might be a significant predictor of poor clinical outcomes (shorter OS and PFS, fewer ORs, less DC) in patients with advanced NSCLC treated with EGFR-TKIs or ICIs as the first-line therapy.

ObjectivesAlthough lipids have been assessed for their possible roles in cancer survival prediction, studies on the association between serum triglyceride (TG) levels and the prognosis of esophageal squamous cell carcinoma (ESCC) patients are limited. This study aimed to evaluate whether serum TG is associated with outcomes in patients with ESCC and investigate any interaction between serum TG and clinical parameters, especially body fat mass.Materials and methodsWe conducted a prospective case study on patients diagnosed with ESCC between March 2012 and November 2018. We measured patients’ serum TG levels before and after treatment. The association between serum TG and overall survival (OS) was evaluated using hazard ratios. We sought to determine a threshold point using optimal stratification. Survival analysis was performed using Kaplan–Meier curves and a Cox proportional hazards model.ResultsOf the 257 participants diagnosed with ESCC, 200 (77.8%) were men. Median follow-up time was 22.4 months (range 3.3–92.4 months). Using univariate Cox proportional hazard analysis and subsequent multivariate analysis, post-TG levels, Karnofsky performance scores, T stages, and chemotherapy cycles were shown to be independent prognostic factors for OS (p < 0.05). The post-TG cut-off point to best classify patients with respect to time to mortality was 1.47 mmol/L. A post-TG level of ≥ 1.47 mmol/L could independently predict a better OS (hazard ratio: 0.55, 95% confidence interval: 0.37–0.79). The associations were consistent across the subtypes of clinical parameters. Furthermore, the post-body mass index, post-subcutaneous adipose tissue area, post-visceral adipose tissue area, post-total adiposity tissue area, and post-total adipose density exhibited a strong positive association with post-TG levels.ConclusionPost-TG levels were found to be a significant positive prognostic biomarker for body fat mass and OS in ESCC patients.

Upregulation of Forkhead box G1 (FOXG1) has recently been observed in many cancers, while its effect on radiosensitivity in glioma is still unclear. In this study, we hypothesized that FOXG1 be a major player in radioresistance of glioma as well as the underlying mechanism.Immunohistochemistry (IHC) was conducted to assess FOXG1 expression in glioma tissues and glioma-adjacent tissues. Western Blot was implemented to detect the expression of autophagy-related proteins. CCK-8, colony formation and flow cytometry assays were implemented to assess cell viability, proliferation and apoptosis, respectively. Transmission electron microscope (TEM) was used to observe autophagic vesicles. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assay was applied to detect the expression of FOXG1.The present study demonstrated that FOXG1 was highly expressed in glioma tissues. FOXG1 expression level was up-regulated in glioma cells following exposure to X-ray irradiation. FOXG1 can attenuate radiosensitivity of glioma cells. Moreover, it revealed that FOXG1 attenuate radiosensitivity of glioma cells by promoting autophagy.The present study suggests that FOXG1 is a pivotal molecule for circumventing radiation-induced cell death in malignant glioma cells through the regulation of autophagy, and it may be a target for the treatment of human brain glioma.

Purpose and objective Auto planning might reduce the manual time required for the optimization and could also potentially improve the overall plan quality. The aim of this study is to demonstrate the statistical comparison of automatic (AU) and manually (MA) generated nasopharyngeal carcinoma (NPC) intensity-modulated radiation therapy (IMRT) plans. Materials and methods The study included 105 nasopharyngeal carcinoma patients, admitted to our hospital. The patients underwent IMRT treatments. The clinically delivered plans were performed with Eclipse (Version 11.0) using manual optimization. The same plans were optimized successively in PinnacleTM3 (version 9.10) treatment planning system using the auto plan software package module. D95 (dose of 95% volume) and D98 (dose of 98% volume) were calculated for the targets and maximum dose (Dmax) and mean dose (Dmean) for the organ at risks (OARs); moreover, the average doses of each target and OARs for 105 patients were evaluated. Results There is no significant difference in the homogeneity of the target between AU and MA treatment plans, while a significant difference is observed for what is concerning the OARs or most of OARs in 105 patients, OAR doses were significantly reduced in AU plan. For OARs which have no significant difference between AU and MA plans are highlighted, the mean dose of OARs in AU plans was at least not higher than MA plans. Conclusion Nasopharyngeal carcinoma IMRT plans made by an automatic planning tool met the clinical requirements for target prescription dose; moreover, the dose of normal tissues was lower than in MA plans. Clinical physicists' time can be saved and the influence of factors such as the lack of experience in treatment planning can be avoided.

To analyze the distribution pattern of lymph nodes (LNs) metastasis of level Ib in nasopharyngeal cancer (NPC) and propose shrinkage of clinical target volume (CTV) boundaries to avoid unnecessary radiation for some space with very low-risk of involvement.Pretreatment images of pathologically proven NPC patients were reviewed and those with positive level Ib LN metastasis was enrolled. The geometric center of each level Ib LN in the neck was marked on a template CT. The spatial relationship of nodes with key structures in level Ib was analyzed. Modified level Ib CTV according to the 2013 International CTV consensus was proposed based on the LN distribution pattern. A PlanIQ Feasibility DVH module was implemented to evaluate the feasibility analysis of the best possible sparing of organs at risk (OAR) with modified Ib CTV.A total of 1518 NPC patients were reviewed and 54 with positive level Ib nodes were enrolled. Four sub-level anatomical regions were defined within the gross area of level Ib. Of 106 positive nodes identified, none, one, 88, and 17 were found in the intraglandular (IG), medial mandibular (MM), supra perivascular (SP), and infra perivascular (IP) sub-level, respectively. This study proposes sparing the IG and MM sub-level and including the area within a specified distance from the submandibular gland (11 mm for SP, 17 mm for IP) for CTV coverage. Compared with planning based on CTV-consensus, planning based on CTV-proposed results in a significantly reduced CTV volume, and mean dose (DBased on detailed analysis of the relationship between positive node distribution and several important anatomical structures, modified level Ib CTV for prophylactic irradiation was proposed to reduce the dose of OAR irradiation.

We aimed to validate the accuracy and clinical value of a novel semisupervised learning framework for gross tumor volume (GTV) delineation in nasopharyngeal carcinoma.Two hundred fifty-eight patients with magnetic resonance imaging data sets were divided into training (n = 180), validation (n = 20), and testing (n = 58) cohorts. Ground truth contours of nasopharynx GTV (GTVnx) and node GTV (GTVnd) were manually delineated by 2 experienced radiation oncologists. Twenty percent (n = 36) labeled and 80% (n = 144) unlabeled images were used to train the model, producing model-generated contours for patients from the testing cohort. Nine experienced experts were invited to revise model-generated GTV in 20 randomly selected patients from the testing cohort. Six junior oncologists were asked to delineate GTV in 12 randomly selected patients from the testing cohort without and with the assistance of the model, and revision degrees were compared under these 2 modes. The Dice similarity coefficient (DSC) was used to quantify the accuracy of the model.The model-generated contours showed a high accuracy compared with ground truth contours, with an average DSC score of 0.83 and 0.80 for GTVnx and GTVnd, respectively. There was no significant difference in DSC score between T1-2 and T3-4 patients (0.81 vs 0.83; P = .223), or between N1-2 and N3 patients (0.80 vs 0.79; P = .807). The mean revision degree was lower than 10% in 19 (95%) patients for GTVnx and in 16 (80%) patients for GTVnd. With assistance of the model, the mean revision degree for GTVnx and GTVnd by junior oncologists was reduced from 25.63% to 7.75% and from 21.38% to 14.44%, respectively. Meanwhile, the delineating efficiency was improved by over 60%.The proposed semisupervised learning-based model showed a high accuracy for delineating GTV of nasopharyngeal carcinoma. It was clinically applicable and could assist junior oncologists to improve GTV contouring accuracy and save contouring time.

Polycrystalline Ba1.5Sr1.5Co2Fe24O41 ceramics were prepared by the sol–gel method with clear grains and grain boundaries having been identified by the scanning electron microscopy. High-temperature colossal dielectric response has been observed and studied through a series of dielectric and impedance measurements. The electrode effect was also studied and the measurement findings reveal that the colossal dielectric permittivity at low frequency is ascribed to the extrinsic effect of Maxwell Wagner polarization. Dielectric relaxation was identified and investigated by the impedance spectra, which is attributed to the thermally activated model. The complex impedance data is simulated with an equivalent electric circuit and the result suggests that the electric response originates from both the grains and grain boundaries. The activation energies of the grains and grain boundaries are calculated which are 0.62 and 0.67 eV, respectively. The comparable activation energies obtained from the complex impedance spectra and DC conductivity indicates that the relaxation may result from the conduction process. Besides, scaling behaviors are observed below 550 K suggesting that the relaxation time is temperature independent.

Background/Aim forkhead box G1 (FOXG1) has recently been observed in many cancers, while its effect on radio-sensitivity in glioma is still unclear. In this study, we hypothesized that FOXG1 be a major players in radio-resistance of glioma as well as the underlying mechanism.Methods Immunohistochemistry (IHC) was conducted to assess FOXG1 expression in the glioma tissues and glioma-adjacent tissues. Western Blot was applied to detect the expression of autophagy-related proteins. CCK-8 and flow cytometry assays were applied to assess proliferation and apoptosis, respectively.Results The present study demonstrated that FOXG1 was highly expressed in glioma tissues. FOXG1 silencing enhances the effect of X-ray irradiation on proliferation inhibition and apoptosis of glioma cells, while FOXG1 overexpression has the opposite effect. Interestingly, the chloroquine (CQ) of autophagy inhibitor enhanced X-ray irradiation induces proliferation inhibition and apoptosis in glioma cells.Conclusions The present study suggests that FOXG1 is a pivotal molecule for circumventing radiation-induced cell death in malignant glioma cells through the regulation of autophagy and provide a target for the treatment of human brain glioma.

In this study the relationship between brain structure and brain metastases (BM) occurrence was analyzed. A model for predicting the time of BM onset in patients with non-small cell lung cancer (NSCLC) was proposed. Twenty patients were used to develop the model, whereas the remaining 69 were used for independent validation and verification of the model. Magnetic resonance images were segmented into cerebrospinal fluid, gray matter (GM), and white matter using voxel-based morphometry. Automatic anatomic labeling template was used to extract 116 brain regions from the GM volume. The elapsed time between the MRI acquisitions and BM diagnosed was analyzed using the least absolute shrinkage and selection operator method. The model was validated using the leave-one-out cross validation (LOOCV) and permutation test. The GM volume of the extracted 11 regions of interest increased with the progression of BM from NSCLC. LOOCV test on the model indicated that the measured and predicted BM onset were highly correlated (r = 0.834, P = 0.0000). For the 69 independent validating patients, accuracy, sensitivity, and specificity of the model for predicting BM occurrence were 70, 75, and 66%, respectively, in 6 months and 74, 82, and 60%, respectively, in 1 year. The extracted brain GM volumes and interval times for BM occurrence were correlated. The established model based on MRI data may reliably predict BM in 6 months or 1 year. Further studies with larger sample size are needed to validate the findings in a clinical setting.

Background The purpose of this study is to compare the efficacy and safety of concurrent chemoradiotherapy (CCRT) versus chemotherapy alone for patients with stage IV esophageal squamous cell carcinoma (ESCC). Methods Eligible patients were retrospectively enrolled at the authors’s institution from January 2010 to October 2015. Of the 141 patients enrolled, 55 (39.0%) received CCRT and 86 (61.0%) received chemotherapy alone. The outcomes and adverse events (AEs) were compared between the two groups. Results The baseline clinical characteristics of the two groups were similar. However, the CCRT group showed a significantly better primary tumor objective response rate (ORR) than that of the chemotherapy group (74.5% versus 45.3%, p = 0.001). The 1-year, 2-year, 3-year overall survival (OS) rates and median OS were 58.0% versus 43.0%, 25.5% versus 14.0%, 10.7% versus 4.7%, and 14 months versus 11 months for patients treated with CCRT or chemotherapy, respectively (p = 0.007). The 1-year and median progression-free survival (PFS) were 29.8% versus 14.9% and 8 months versus 6 months (p = 0.005). Multivariate analysis identified CCRT (p = 0.013) and solitary metastasis (p = 0.037) as independent factors for greater OS. The frequency of leucocytopenia (grade 3 or higher) was significantly higher in the CCRT group than in the chemotherapy-alone group (p = 0.040), whereas the rates of other AEs did not differ. Conclusions In this study, it is suggested that CCRT is more effective than chemotherapy alone for stage IV ESCC, yielding better primary responses and survival outcomes with tolerable side effects.

Purpose To report an implementation method and the results of independent brachytherapy dose verification software (DVS). Material and methods The DVS was developed based on Visual C++ and adopted a modular structure design. The DICOM RT files exported from a treatment planning system (TPS) were automatically loaded into the DVS. The DVS used the TG-43 formalism for dose calculation. A total of 15 cervical cancer patients who underwent brachytherapy were retrospectively selected to test the DVS. Dosimetric parameters and γ analysis (0.1 cm, 5%) were used to evaluate the dose differences between the DVS and the TPS. Results Compared with the TPS dose, the γ pass rates of the dose calculated by the DVS were higher than 98%. For the clinical target volume (CTV), the dosimetric differences were less than 0.63% for D90% and D100%. For the bladder, rectum, and sigmoid, the agreement of D0.1cc, D1cc, and D2cc were within a 0.78% level. Conclusions With minimal human-computer interactions, the DVS can verify the accuracy of doses calculated by the TPS.

Aims and background Esophageal cancer can cause substantial mortality and there is controversy about the effectiveness of concurrent and sequential chemoradiotherapy (CRT) for this disease. Methods and Study Design Based on established criteria, we searched electronic databases including PubMed, Excerpta Medica Database (Embase), China National Knowledge Infrastruction (CNKI), Wanfang, and Weipu databases up to March 2014 to collect eligible studies. Relative risks (RRs) and their 95% confidence intervals (CIs) were calculated. Q and I2 test were applied to test statistical heterogeneities among studies. Publication bias of total effective rate was evaluated through a funnel plot and sensitive analysis was conducted. Results We identified 10 Chinese studies including 1024 esophageal cancer patients. The RRs of total effective rate and 1-, 2-, and 3-year survival rate for concurrent versus sequential CRT were 1.15 (95% CI 1.07 to 1.24), 1.15 (95% CI 1.05 to 1.26), 1.44 (95% CI 1.21 to 1.73), and 1.66 (95% CI 1.37 to 2.01), respectively, all with statistically significant differences (pConclusions Concurrent CRT was superior to sequential CRT for esophageal cancer management among Chinese people. Though higher toxic effects were revealed in concurrent CRT, it was tolerable. Therefore, concurrent CRT could be applied into esophageal cancer treatments for Chinese patients.

Nasopharyngeal carcinoma (NPC) is a rare malignancy worldwide, but it is endemic in a few areas including Southern China, Southeast Asia, North Africa and the Arctic. The underlying mechanisms behind this remarkable geographic distribution remain unclear. Although Epstein-Barr virus (EBV) infection has been suggested as a necessary cause of undifferentiated NPC, EBV itself is not sufficient to cause this malignancy. Other co-factors, such as environmental risk factors, and/or genetic susceptibility, may interact with EBV to play a role in the carcinogenesis of NPC. Survival rates differ significantly between NPC patients in early stages and late stages. Due to the close associations between EBV infection and NPC risk, EBV-related biomarkers have been used for early detection and screening for NPC in a few high-incidence areas. In the present review article the latest updates are discussed.

Telomerase maintains the length of telomeric DNA at the end of chromosomes; stabilizes the functions of chromosomes, protects the structure of chromosome DNA and regulates normal cell growth. The length and stability of telomeres determine the cellular lifespan, furthermore, they correlate with cellular aging and carcinogenesis. Researches on the role of telomerase in degenerative diseases and cancers show that it regulates cellular senescence in degenerative diseases. Although telomerase is not an oncogene, it does make tumor cells immortal by maintaining the stability of telomeric DNA. Telomerase-based therapies have become a hotspot in new anticancer and degenerative diseases treatments. This review aims to provide a comprehensive understanding of the role of telomerase and telomere in cellular senescence and cancer.

The ZnO-based ceramic films doped with Bi2O3, Sb2O3, MnO, Co2O3 and Cr2O3 were prepared for use as film varistors by a sol–gel method. The formation and the changes of the phases in the films doped with different dopants and annealed at different temperatures were investigated via X-ray diffraction analysis. Three secondary phases, i.e., Bi2O3, Zn7Sb2O12 spinel and ZnCr2O4, were detected in the films when the annealing temperature was above 550 °C. The lattice constants of ZnO and Zn7Sb2O12 spinel phase changed with dopants and the annealing temperature, indicating that the diffusion of the ions into the crystals of ZnO and spinel phase had taken placed. The redistribution of the ions changed the constituents of the intergranular phases and the relevant defect species in ZnO grains, and affected intensively the electrical properties of the films, which were used as film varistors. The highest nonlinear coefficient (α) with the lowest leakage current was achieved when the film, which was doped with Bi2O3, Sb2O3, MnO and Cr2O3, was annealed at 750 °C.

SiO2-doped Ba0.85Sr0.15TiO3 (SBST) glass–ceramic (g–c) films with perovskite structure have been prepared on Pt/Ti/SiO2/Si substrates by sol–gel technique. Differential thermal analysis (DTA), X-ray diffraction (XRD) and atomic force microscopy (AFM) are employed to analyze the synthesize process and microstructure of SBST g–c films. The ferroelectricity and crystallization behavior of SBST films are discussed. It is found that the starting synthesize temperature of SBST15 film is larger than that of pure barium strontium titanate (BST) film for about 60 °C. The grain sizes decrease and the ferroelectricity of SBST g–c films is degenerated, but their loss tangent and leakage current density decrease with increasing SiO2 contents. The temperature coefficient of dielectric (TCD) and the pyroelectric coefficient γ of the films are measured. The results show that TCD and the pyroelectric coefficient γ of SBST5 film at 20–25 °C are, respectively, 4.6% °C−1 and 8.1×10−8 C cm−2 K−1, which is about 2/3 value of the pure BST films. BST g–c film with 5 mol% SiO2 dopant is hopeful to be the advanced candidate material for uncooled infrared focal plane arrays (UFPAs) applied at near room temperature.

ZnO-glass ceramic films doped with Sb2O3, MnO, Co2O3 and Cr2O3 were fabricated by a novel sol-gel process. The precursors were prepared by dispersing the ZnO nano-powders throughout into the sols, which were prepared by dissolving zinc acetate dihydrate and the dopants into 2-methoxyethanol and stabilized by diethanolamine and glacial acetate. The films were prepared on Au/Si substrates by spin coating method and were heat-treated and annealed in air at 450 and 750 °C, respectively. The films with the thickness of about 2 µm were obtained after 10-20-layers deposition. The crystal phases, the residual stress in the crystals and the microstructure of films were studied via XRD analysis, Raman spectroscopy and SEM, respectively. The films were used as film varistors after the upper Au electrodes, the area of which is 3 mm2, were made on the surface of the films by vacuum evaporation. The electrical properties were studied by varistor characteristics testing instrument, and the remarkable nonlinear V-I response was observed. The nonlinear voltage and the nonlinear coefficient (α), which were 3-19 V and 5-15, respectively, were affected obviously by glass content. The highest nonlinearity coefficient with nonlinear voltage of 6.5 V could be achieved when the films contain 8 wt% glass.

(Ba1−xSrx)TiO3 (BST) thin films with different compositions have been prepared on Pt/Ti/SiO2/Si substrates by an improved sol–gel technique. DTA–TGA, XRD and SEM are employed to analyze the thermolysis process of BST gel. The dielectric and ferroelectric properties of BST thin films were measured. The results show that the films exhibit pure perovskite phase through rapid thermal anneal (RTA) above 650 °C and their grain size is about 50–100 nm. The dielectric constants of BT, BST5, BST10 and BST15 are 320, 375, 400 and 425, respectively, at 25 °C and 10 kHz. Their loss tangents are 0.035, 0.041, 0.024 and 0.01, respectively. The remnant polarization, Pr, and coercive field, Ec, of BST10 thin film are 2.5 μC cm−2 and 50 kV cm−1, respectively, and the maximal pyroelectric coefficient reaches 12×10−8 C cm−2 K−1 at 35 °C. BST15 thin film is the advanced candidate material for uncooled infrared focal plane arrays (UFPAs) applied at near ambient temperature.

Lead zirconate titanate (Pb(Zr 0.53 Ti 0.47 )O 3 , PZT) ferroelectric films with 2–60 μm in thickness have been successfully fabricated on Pt-coated oxidized Si substrates(Pt/Ti/SiO 2 /Si) by a new sol–gel based 0-3 method. The films consisted of 0-3 ceramic/ceramic composites formed by dispersing nanopowders in a PZT solution. The precursor solution for spin coating was prepared from lead acetate, tetrabutyl titanate, and zirconium nitrate. The microstructure and morphology of the prepared PZT thick films were investigated by X-ray diffractometry and scanning electron microscopy techniques. The XRD analysis indicates that the thick films possess single-phase perovskite type structure and no pyrochlore phase exists. The SEM micrograph shows that the PZT thick films were of uniformity, density and crack-free. Dielectric constant of 860, loss tangent of 0.03, remnant polarization of 25 μC cm −2 , a coercive field of 40 kV cm −1 were obtained on 50 μm thick films annealed at 700 °C.

The crystalline properties of sol-gel derived lead-based ferroelectric thin films on several kinds of substrates were investigated. The polycrystalline lead zirconium titanate (PZT), lead lanthanum titanate (PLT) and PbTiO 3 ferroelectric thin films, the highly oriented PbTiO 3 ferroelectric thin films and the epitaxial growth PZT, PLT ferroelectric thin films with perovskite-type structure were prepared by the sol-gel method. Lead-based ferroelectric thin films had good ferroelectricity. The remanent polarization P r and coercive field E c of Pb(Zr 0.5 Ti 0.5 )O 3 ceramic thin films at 1 kHz were 20 μC cm -2 and 40 kV cm -1 respectively. P r and E c of the PLTIS ceramic thin films at 1 kHz were 17 μC cm -2 and 46 kV cm -1 respectively. P r and E c of the PbTiO 3 ceramic thin films at 50 Hz were 15 μC cm -2 and 80 kV cm -1 respectively. Lead-based ferroelectric thin films had good pyroelectricity. The pyroelectric coefficients y of the PLT5, PLT10, PLT15 and PbTiO 3 ceramic thin films at room temperature were 3.37 X 10 -8 C cm -2 K -1 , 5.25 X 10 -8 C cm -2 K -1 , 7.10 X 10 -8 C cm -2 K -1 and 2.9 X 10 -8 C cm -2 K -1 respectively. The dielectric constants e γ of PLT and PbTiO 3 ceramic thin films were about 200 and 150. The dielectric losses tan 8 of PLT and PbTiO 3 ceramic thin films were about 0.02 and 0.01 respectively.

e19008 Background: Stage IV non-small cell lung cancer (NSCLC) carries a poor prognosis with a median survivals of 8-10 months. The standard treatment has traditionally been systemic chemotherapy a...

4035 Background: Recombinant human endostatin (endostar) has been documented to be an inhibitor of tumor angiogenesis. The aim of this randomized phase II study was to assess the efficacy and safet...

Yttrium-modified Pb(Zr,Ti)O 3 (PYZT) ferroelectric thin films have been prepared by the sol–gel technique. The annealing temperature and time of the thin films are 600–700°C for 1–10 min in 100% O 2 atmosphere. The influence of the yttrium contents on the ferroelectric properties of PZT thin films has been studied. Experimental results show that PZT ferroelectric thin films doped with yttrium have a large remanent polarization P r , small coercive field E c , small leakage current, good fatigue endurance and lower annealing temperature than the undoped PZT thin films. 2.5 mol% Y is adequate to obtain better ferroelectric properties. The values of P r and E c of (Pb 0.975 Y 0.025 )(Zr 0.53 Ti 0.47 )O 3 thin films are 30 μC cm −2 and 40 kV cm −1 at 1 kHz, respectively.