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1.
Micromachines (Basel) ; 12(8)2021 Jul 28.
Article En | MEDLINE | ID: mdl-34442516

A quartz crystal resonator (QCR) is an indispensable electronic component in the field of the modern electronics industry. By designing and depositing electrodes of different shapes and thicknesses on a quartz wafer with a certain fundamental frequency, the desired target frequency can be obtained. Affected by factors such as the deposition equipment, mask, wafer size and placement position, it is difficult to accurately obtain the target frequency at a given time, especially for mass-produced QCRs. In this work, a laser with a wavelength of 532 nm was used to thin the electrodes of a QCR with a fundamental frequency of 10 MHz. The electrode surface was etched through a preset processing pattern to form a processing method of local thinning of the electrode surface. At the same time, the effect of laser etching on silicon dioxide and resonator performance was analyzed. Satisfactory trimming frequency-increasing results were achieved, such as a frequency modulation accuracy of 1 ppm, frequency distribution with good consistency and equivalent parameters with small changes, by the laser partial etching of the resonator electrode. However, when the surface electrode was etched into using through-holes, the attenuation amplitude of the equivalent parameter became larger, especially in terms of the quality factor (Q), which decreased from 63 K to 1 K, and some resonators which had a serious frequency drift of >40%. In this case, a certain number of QCRs were no longer excited to vibrate, which was due to the disappearance of the piezoelectric effect caused by the local thermal phase change in the quartz wafer.

2.
Phys Chem Chem Phys ; 23(19): 11466-11471, 2021 May 19.
Article En | MEDLINE | ID: mdl-33959738

Using first-principles calculations, we identify a robust R30° reconstruction of a Si3 trimer bilayer on the Si(111) surface with a La coverage of 2/3 monolayer. Each surface unit cell contains two Si3 trimers and two La atoms, where the upper Si3 trimer is located just above the lower one with a rotation of about 60°, while two La atoms with different heights are distributed between the Si3 trimers and located on the T4 top site of the Si(111) surface, forming a honeycomb-like network structure. We find that the two La atoms have different valence states, La2+ and La3+, respectively. The high structural stability is attributed to the lower La atom saturating all the three dangling bonds of the upper Si3 trimer, while the higher La atom compensates two electrons to the lower Si3 trimer. The electronic band structure and band-decomposed charge density distribution show a semiconducting characteristic with a small surface band gap of 42 meV. Moreover, simulated STM images show a good structural match with the recent experimental observations.

3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(2): 320-4, 2015 Feb.
Article Zh | MEDLINE | ID: mdl-25970885

ZnS/CdS composite window layer was prepared by magnetron sputtering method and then applied to CdTe solar cell. The morphology and structure of films were measured. The data of I-V in light and the quantum efficiency of CdTe solar cells with different window layers were also measured. The effect of ZnS films prepared in different conditions on the performance of CdTe solar cells was researched. The effects of both CdS thickness and ZnS/CdS composite layer on the transmission in short wavelength were studied. Particularly, the quantum efficiency of CdTe solar cells with ZnS/CdS window layer was measured. The results show as follows. With the thickness of CdS window layer reducing from 100 to 50 nm, the transmission increase 18.3% averagely in short wavelength and the quantum efficiency of CdTe solar cells increase 27.6% averagely. The grain size of ZnS prepared in 250 degrees C is smaller than prepared at room temperature. The performance of CdTe solar cells with ZnS/CdS window layer is much better if ZnS deposited at 250 degrees C. This indicates grain size has some effect on the electron transportation. When the CdS holds the same thickness, the transmission of ZnS/CdS window layer was improved about 2% in short wavelength compared with CdS window layer. The quantum efficiency of CdTe solar cells with ZnS/CdS window layer was also improved about 2% in short wavelength compared with that based on CdS window layer. These indicate ZnS/CdS composite window layer can increase the photon transmission in short wavelength so that more photons can be absorbed by the absorbent layer of CdTe solar cells.

4.
Biomed Pharmacother ; 68(7): 825-31, 2014 Sep.
Article En | MEDLINE | ID: mdl-25260839

OBJECTIVE: To study the influence of the methylation level of UGT1A1 gene related to CPT-11 metabolic enzymes in colorectal cancer cells on the sensitivity of chemotherapy drugs. METHODS: Test the changes in sensitivity of seven colorectal cancer cell strains that have been/not been subject to DAC treatment to CPT-11, analyze its correlation with CES2, UGT1A1 and GUSB mRNA expression according to IC50; screen the effective interference sequence of UGT1A1 siRNA, test the changes in cytotoxicity of CPT-11 after UGT1A1 siRNA is transfected, select RK0 cells and make them transfected with the chemosynthetic UGT1A1 siRNA after their UGT1A1 expression is restored with or without demethylation treatment. RESULTS: The sensitivity of different colorectal cancer cell strains to CPT-11 showed difference (P<0.05), UGT1A1 expression in colorectal cell lines had a negative correlation with the IC50 (r=0.790648, P<0.05), the interference efficiency of the screened UGT1A1 siRNA was up to 78%. The IC50 value of siRNA decreased by nearly one time after transfected with HT-29 (P<0.01); which of methylated RK0 cells of UGT1A1 gene increased instead after the demethylation treatment. However, the IC50 value of the demethylation treatment group increased compared with the non-demethylation treatment group after UGT1A1 siRNA was transfected. CONCLUSIONS: The cytotoxicity of CPT-11 to colorectal cancer cells has a negative correlation with UGT1A1 expression, and positive correlation with CES2 and GUSB. The specific silencing UGT1A1 gene of siRNA could significantly increase the sensitivity of CPT-11 to the chemotherapy of colorectal cancer cells. UGT1A1 methylation was an important factor affecting the chemosensitivity of CPT-11.


Camptothecin/analogs & derivatives , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , DNA Methylation/genetics , Glucuronosyltransferase/genetics , Antineoplastic Agents/pharmacology , Camptothecin/pharmacology , Carboxylesterase/genetics , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/drug effects , Gene Expression Regulation, Neoplastic/genetics , HCT116 Cells , HT29 Cells , Humans , Irinotecan , RNA, Small Interfering/genetics , Transfection/methods
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(4): 888-93, 2014 Apr.
Article En | MEDLINE | ID: mdl-25007593

The effects of device performance of 1.7 MeV electron irradiation on cadmium telluride polycrystalline thin film solar cells with the structure of anti-radiation glass/ITO/ZnO/CdS/CdTe/ZnTe/ZnTe : Cu/Ni have been studied. Light and dark I-V characteristics, dark C-V characteristics, quantum efficiency (QE), admittance spectrum (AS) and other testing methods were used to analyze cells performance such as the open-circuit voltage (Voc), short-circuit current (Isc), fill factor (FF) and conversion efficiency (eta). It was explored to find out the effects of irradiation on the current transfer characteristic of solar cells combined with the dark current density (Jo), diode ideal factor (A), quantum efficiency, carrier concentration and the depletion layer width. The decline in short-circuit current was very large and the efficiency of solar cells decreased obviously after irradiation. Reverse saturation current density increased, which indicates that p-n junction characteristics of solar cells were damaged, and diode ideal factor was almost the same, so current transport mechanism of solar cells has not changed. Quantum efficiency curves proved that the damage of solar cells' p-n junction influenced the collection of photo-generated carriers. Irradiation made carrier concentration reduce to 40.6%. The analyses have shown that. A new defect was induced by electron irradiation, whose position is close to 0.58 eV above the valence band in the forbidden band, and capture cross section is 1.78 x 10(-16) cm2. These results indicate that irradiation influences the generation of photo-generated carriers, increases the risk of the carrier recombination and the reverse dark current, and eventually makes the short-circuit current of solar cells decay.

6.
Oncol Lett ; 8(1): 190-192, 2014 Jul.
Article En | MEDLINE | ID: mdl-24959243

Compared with female breast cancer, male breast cancer (MBC) has an extremely low morbidity, later staging and fewer breast tissues. The lumps are easier to invade in the center and the majority of the cases are positive for metastatic lymph node, with the typical clinical manifestation as a painless mass in partial breast. MBC with an unknown primary tumor is rare and is often prone to misdiagnosis, resulting in a delay in correct treatment. Such a case is extremely significant for clinical reference. The current study presents a 58-year-old male who developed a painless mass in the left armpit and received armpit mass biopsy and pathological examination which showed glandular cancer, with a high possibility of mammary primary tumor. The patient was administered four cycles of paclitaxel plus oxaliplatin chemotherapy. However, three months later, the patient identified novel disseminated lymph nodes in the left armpit. The initial pathological section and paraffin blocks were re-examined and the patient was finally diagnosed with breast invasive ductal carcinoma based on the metastases pathology and immunohistochemical examination. No breast mass was found on physical examination of the patient and the tumor markers, including cancer antigen 125 and carcinoembryonic antigen, were normal. No primary tumors were observed in the mammography and PET-CT and the primary tumor was not found following the left breast modified radical mastectomy.

7.
Biomed Pharmacother ; 68(1): 31-7, 2014 Feb.
Article En | MEDLINE | ID: mdl-24439671

OBJECTIVE: To evaluate the aberrant methylation gene expression related to the irinotecan (CPT-11) metabolic enzymes in different colorectal cancer cell strains; provide new thoughts and measures for reverse of tumor drug resistance. METHODS: Studied the aberrant methylation state of CES2, UGT1A1 and GUSB in eight colorectal cancer cell strains through MSP method; and analyze the expression of the target gene after being dealt with DAC. RESULTS: UGT1A1 showed methylation in five cell strains, while CES2 and GUSB respectively showed consistent unmethylation or hemimethylation. After being dealt with DAC, CES2 and GUSB mRNA showed different expressions but not significant. The expression quantity of UGT1A1mRNA in the low-expression cell strains increased significantly. The expression of UGT1A1 protein where POSITIVE presented low expression was up-regulated to different degrees. Negative tropism was found in CES2 and UGT1A1. CONCLUSION: Methylation in UGT1A1 gene expression silencing as an important mechanism; methylation could provide an effective target for methylation regulation intervening in the treatment of CPT-11. Meanwhile, studies found that the changes in expressions of CES2 and GUSB might be resulted from some unknown target that still existed during the regulation, or from the influence of methylation in the non-core zone of promoters on the gene transcription.


Antineoplastic Agents, Phytogenic/metabolism , Camptothecin/analogs & derivatives , Colorectal Neoplasms/genetics , Glucuronosyltransferase/genetics , Camptothecin/metabolism , Carboxylesterase/genetics , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/metabolism , DNA Methylation , Gene Expression Regulation, Neoplastic , Gene Silencing , Glucuronidase/genetics , Humans , Irinotecan , Promoter Regions, Genetic/genetics , RNA, Messenger/metabolism , Tumor Cells, Cultured , Up-Regulation/genetics
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(5): 1295-8, 2013 May.
Article Zh | MEDLINE | ID: mdl-23905339

Cd1-xZnxTe:Cu Thin films were prepared by co-evaporation method. X-ray Fluorescence Spectrometry (XRF), scanning electron microscope(SEM), UV-Vis transmission spectra, thermal probe, four-probe method, step profiler and X-ray diffractometer (XRD) were used to investigate the composition, structure, morphology, optical and electrical properties of Cd1-x ZnxTe:Cu thin films with different doping concentration. The results show that the resistivity of 10% copper doped Cd1-x ZnxTe films increased several magnitude and the conductive type changed from p-type to n-type after annealing. The 20% cu-doped Cdl, Zn,Te films had not obvious change in conductive type and electrical resistivity after annealing and they exhibit good surface morphology. The transmissivity of 30% cu-doped Cd1-x, ZnxTe films decreased seriously below 10% after annealing, which indicate that they are not suitable to be the top cell materials in tandem structure. The 20% and 30% cu-doped Cd1-x Zn, Te films were both p-type conductivity.

9.
Zhong Xi Yi Jie He Xue Bao ; 10(6): 635-40, 2012 Jun.
Article Zh | MEDLINE | ID: mdl-22704411

BACKGROUND: Chemotherapy completion rate can reflect the tolerance and compliance of patients to chemotherapy. Poor tolerance may result in delay or suspension of the comprehensive treatment plan, thus affect the efficacy of cancer treatment. Evaluating methods to improve the completion rate of chemotherapy and reduce the occurrence of delayed chemotherapy has gained increasing attention and is the significant area of study in the field of cancer treatment. Studies have shown that Chinese medicine combined with chemotherapy could improve the quality of life in patients with stage IIIB/IV non-small-cell lung cancer (NSCLC). OBJECTIVE: To observe the effects of Feitai Capsule, a Chinese patent herbal drug, combined with chemotherapy in patients with stage IIIB/IV NSCLC. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: A total of 60 diagnosed stage IIIB/IV NSCLC patients from the Department of Oncology, Fuzhou General Hosipital of Najing Military Region were randomly divided into treatment group (30 cases) and control group (30 cases). Patients in the treatment group were treated with chemotherapy plus Feitai Capsule and patients in the control group only received chemotherapy. Both groups of patients were treated for 4 therapeutic cycles. MAIN OUTCOME MEASURES: The chemotherapy completion rate and the chemotherapy delay rate were observed in each cycle of treatment. The therapeutic efficacy was evaluated after 4 cycles. RESULTS: The chemotherapy completion rate was 96.42% in the treatment group, while that of the control group was 74.07%. The chemotherapy delay rate was 3.57% in the treatment group, while that of the control group was 14.8% (P=0.007 0). The disease control rate was 78.6% in the treatment group, while that of the control group was 59.3% (P=0.173 9). CONCLUSION: Feitai Capsule can increase the chemotherapy completion rate in patients with stage IIIB/IV NSCLC.


Carcinoma, Non-Small-Cell Lung/drug therapy , Drugs, Chinese Herbal/therapeutic use , Lung Neoplasms/drug therapy , Phytotherapy , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Capsules , Carcinoma, Non-Small-Cell Lung/pathology , Female , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Treatment Outcome
10.
Chin J Integr Med ; 18(2): 106-11, 2012 Feb.
Article En | MEDLINE | ID: mdl-22311406

OBJECTIVE: To examine the effect of a Chinese medicinal herbal formula (Feitai Capsule, ) on the quality of life (QOL) and progression-free survival (PFS) of patients with unresectable non-small cell lung cancer (NSCLC). METHODS: Sixty-two patients were randomly divided into the treatment group (31 cases) and the control group (31 cases). For the treatment group, 4 capsules (1.2 g/capsule) of Feitai Capsule were administered 3 times a day after meals for 3 weeks; then no drug was administered for 1 week. This schedule was continued for at least 3 more cycles (12 weeks totally). If there were no obvious toxic reactions, the treatment was extended. The patients were evaluated at least once every 8 weeks until progressive disease (PD). For the control group, the regular follow-up and evaluation were performed at least once every 8 weeks until PD. Clinical symptoms, objective response, physical constitution and energy, QOL, and PFS were evaluated regularly. Analysis of variance (ANOVA), a non-parametric test, and analysis of covariance were used to compare clinical features, amelioration of clinical symptoms, physical constitution and energy, and QOL. Kaplan-Meier analysis was used to compare the two-group PFS. RESULTS: Sixty patients finished the final evaluation, with 30 patients in each group. Baseline characters between groups were not significantly different (P>0.05). The control group had a 36.7% improvement in clinical symptoms, while the treatment group had a 73.3% improvement. This difference was statistically significant (Z= -2.632, P=0.008). The control group had a 26.7% improvement in the Karnofsky performance status (KPS), while the treatment group had a 53.4% improvement. This was also significantly different (Z=-2.182, P=0.029). A comparative analysis indicated a positive correlation (r=0.917, P<0.001). Compared with the control group, QOL in the treatment group was significantly improved, except in the social/family condition and doctor-patient relationship indicators. The PFS of the treatment group and control group were 6.23 months and 4.67 months, respectively (P=0.048). CONCLUSION: Feitai Capsule, a Chinese medicinal herbal treatment could improve the QOL and extend the PFS of the unresectable NSCLC patients.


Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/surgery , Drugs, Chinese Herbal/therapeutic use , Lung Neoplasms/drug therapy , Lung Neoplasms/surgery , Quality of Life , Adult , Aged , Capsules , Case-Control Studies , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged
11.
Clin Chem Lab Med ; 48(12): 1733-7, 2010 Dec.
Article En | MEDLINE | ID: mdl-20704542

BACKGROUND: The goal of this study was to evaluate plasma D-dimer as a diagnostic marker for exclusion of suspected aortic dissection (AD). METHODS: Two-hundred and sixty suspected AD patients were enrolled, including acute AD, n=107; chronic AD, n=17; acute myocardial infarction (AMI), n=70; pulmonary embolism (PE), n=18; non-ST elevation myocardial infarction (NSTEMI), n=28; and unstable angina (UA), n=20. All patients had D-dimer testing performed (Roche Diagnostics GmbH) immediately following admission. RESULTS: The D-dimer concentrations in both the acute AD group [median: 3.47; 95% confidence interval (CI): 2.43-4.50 µg/mL] and chronic AD group (median: 1.09; 95% CI: 0.36-3.81 µg/mL) were significantly higher than those in patients in the AMI, NSTEMI and UA groups (p=0.000), but not when compared to the PE group. One (0.8%) patient was identified in the acute AD group who presented with a low D-dimer value (0.04 µg/mL), indicating the existence of intramural hematoma as demonstrated by CT. CONCLUSIONS: D-dimer may be used as a potential marker for suspected AD, with high sensitivity of up to 99.2% (1/124). Regardless of the cut-off threshold selected, the sensitivity of D-dimer was unable to reach 100%. Further examinations, including imaging technology, were necessary to diagnose the suspected AD patients who had negative D-dimer result.


Aortic Aneurysm/diagnosis , Aortic Dissection/diagnosis , Fibrin Fibrinogen Degradation Products/analysis , Biomarkers , Diagnosis, Differential , Diagnostic Imaging , Humans , Sensitivity and Specificity
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(3): 753-6, 2010 Mar.
Article Zh | MEDLINE | ID: mdl-20496702

Polycrystalline CdTe thin films were prepared by close-spaced sublimation (CCS) and were annealed in different condition. The thin films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy(XPS). The content distribution and valence state of all elements after annealing were studied. All results show that the as-deposited CdTe thin films are in a cubic phase and have the preferred orientation in (111) direction. After annealing, the peak intensity of (111), (220), (311) grows and the crystal grains grow up, while the crystal boundary decreases. So the compound probabilities of current carrier decrease, therefore shunt resistance and drain current are improved. From detailed analysis of X-ray photoelectron data, it is proposed that tellurium oxides present and its content reduces with depth increasing and that there are TeCl2O building blocks.

13.
Zhong Xi Yi Jie He Xue Bao ; 7(7): 611-5, 2009 Jul.
Article Zh | MEDLINE | ID: mdl-19615313

BACKGROUND: Recently the maintenance therapy of non-small-cell lung cancer (NSCLC) patients who completed required treatment cycles has caused widespread interests in the medical field. Traditional Chinese medicine may be a useful complement in maintenance treatment of mid-to-late stage NSCLC. OBJECTIVE: To observe the effects of Feitai Capsule, a compound traditional Chinese herbal medicine for expelling blood stasis and phlegm, on the quality of life of the NSCLC patients as a maintenance treatment. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: A total of 62 mid-to-late stage NSCLC patients from Fuzhou General Hospital of Nanjing Military Region were included and randomly divided into treatment group (31 cases) and control group (31 cases). Patients in the treatment group were treated with Feitai Capsule, and patients in the control group did not accept any intervention. Regular observations and follow-up were performed for patients in the two groups. MAIN OUTCOME MEASURES: Analysis of variance, nonparametric test, and analysis of covariance were used to compare clinical features, amelioration of clinical symptoms, physical constitution and energy, and quality of life. RESULTS: There were two dropouts and 60 valid cases. The baseline characteristics of the two groups were similar. In the treatment group, symptom response and physical energy level were improved by 36.6% (Z=-2.632, P=0.008) and 26.7%(Z=-2.182, P=0.029), respectively. There was a positive correlation between these two factors (r=0.917, P<0.001). The patients in treatment group had a significantly improved quality of life after treatment. No serious adverse events were observed. CONCLUSION: Feitai Capsule as maintenance treatment can improve the quality of life of the patients with mild-to-late stage NSCLC.


Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Drugs, Chinese Herbal/therapeutic use , Lung Neoplasms/drug therapy , Phytotherapy , Adult , Aged , Capsules , Female , Humans , Male , Middle Aged , Quality of Life
14.
Ultrasonics ; 44 Suppl 1: e1365-9, 2006 Dec 22.
Article En | MEDLINE | ID: mdl-16806379

In the present study, the possibility of using leaky Rayleigh waves as a nondestructive tool for the evaluation of CVD diamond coating layer is explored experimentally. For this purpose, a set of CVD diamond coated specimens are prepared and the leaky Rayleigh waves are measured in an immersion, pulse-echo setup. For the proper analysis of the acquired signals we propose a novel signal analysis approach, namely the "time trace angular scan (TTAS)" image. Then, the proposed approach together with the backward radiation profiles are applied for the analysis of signals acquired in the initial experiments. The TTAS image shows the entire information on both time-of-arrival and angle of incidence of the signals for the proper "time-angle windowing." Then, the backward radiation profile of the windowed signals provides adequate parameters from which nondestructive evaluation of the coated specimens is carried out.

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