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The study used multi-layer graphene, synthesized by thermal chemical vapor deposition, as the material for a homo-junction pn device formation. Due to the oxygen adsorption in air, the synthesized pristine graphene behaved as a p-type semiconductor. In order to modulate the graphene semiconductor type, the nitrogen plasma treatment with radio-frequency power as a parameter was used to transfer the semiconductor characteristics. The graphene-based field-effect transistor transfer characteristics were subsequently measured to confirm whether the modified graphene was p-type or n-type. Different nitrogen doping levels affected the diode properties differently. It demonstrated that the rectification effect of the formed pn device was clearly observed using this simple strategy. We also successfully produced this graphene lateral pn device applying a half-wave rectification circuit. The effective formed pn device can be further applied in bipolar junction transistor development. [ABSTRACT FROM AUTHOR]

This study investigated the antioxidant and anti-inflammatory properties of the fractionated tea extract, a lower-polymerized polyphenol-rich extract ultrafiltrated from oolong tea. The amounts of total polyphenols, flavonoids and condensed tannin were enriched in fractionated tea extract compared to oolong tea. Furthermore, fractionated tea extract was a stronger scavenger of nitric oxide and 2,2-diphenyl-1-picryhydrazyl radicals than oolong tea. When lipopolysaccharide-treated RAW264.7 macrophages were co-incubated with both tea extracts (500 μg/mL) or (-)-epigallocatechin gallate (100 μg/mL) for 16 h, all samples (oolong tea, fractionated tea extract, and (-)-epigallocatechin gallate) suppressed nitric oxide production by 60, 48, and 46%, respectively, and the suppression was due to nitric oxide-scavenging. However, only fractionated tea extract lowered the proportion of phospholipid arachidonic acid and type II-cyclooxygenase expression, thereby decreasing PGE2synthesis by 29%. In conclusion, fractionated tea extract was rich in potent antioxidant substances capable of inhibiting the production of pro-inflammatory mediators. [ABSTRACT FROM PUBLISHER]

The effects of Li2 O- ZnO- B2 O3 ( LZB) glass addition on densification and dielectric properties of Ba4( Nd0.85 Bi0.15)9.33 Ti18 O54 ( BNBT) have been investigated. At a given ratio of ZnO/ B2 O3, the glass softening point decreases, but the thermal expansion coefficient and dielectric constant increase with increasing Li2 O content in the LZB glass. With 10 vol% LZB glass, the densification temperature reduces greatly from 1300°C for pure BNBT to 875°C-900°C for BNBT + LZB dielectric, and the densification enhancement becomes more significant with increasing Li2 O content in the LZB glass. The above result is attributed to a chemical reaction taking place at the interface of LZB/ BNBT during firing, which becomes less extensive with increasing Li2 O content in the LZB glass. Therefore, more residual LZB glass, which acts as a densification promoter to BNBT, is left with increasing Li2 O content. For the LZB glass with a Li2 O content in the range 10-30 mol%, the resulting 90 vol% BNBT + 10 vol% LZB microwave dielectric has a dielectric constant of 55-70, product ( Q × fr) of quality factor ( Q) and resonant frequency ( fr) of 1000-3000 GHz at 5-5.79 GHz, and a temperature coefficient of resonant frequency (τf) of 10-60 ppm/°C in the temperature range between 25°C and 80°C. [ABSTRACT FROM AUTHOR]

BACKGROUND: The authors investigated the clinical implication of plasma Epstein-Barr virus (EBV) DNA assay and 18F-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography (PET) in the detection of recurrent nasopharyngeal carcinoma (NPC). METHODS: Two hundred forty-five patients with NPC who had previously received treatment and were in a state of remission were monitored prospectively using a plasma EBV DNA assay every 3 to 6 months. 18F-FDG PET studies were obtained when abnormal EBV DNA or clinically suggestive signs of recurrence were noted. RESULTS: Thirty-six of 245 patients (14.7%) patients had abnormal EBV DNA tests and underwent PET scans. In the remaining 209 patients, 3658 blood tests were negative. PET scans also were obtained in 5 patients who had undetectable EBV DNA levels but signs that were clinically suggestive of disease recurrence. Subsequent analyses focused on 41 patients who had PET studies. In lesion-based analyses, the sensitivity, specificity, and accuracy of PET by visual interpretation were 81.8%, 77.1%, and 79.2%, respectively, for all 125 lesions. In patient-based analyses, the accuracy of PET by visual interpretation was 51.2%. All 36 patients who had detectable plasma levels of EBV DNA had demonstrable NPC recurrences, whereas no recurrences were noted in 5 patients who had undetectable EBV DNA levels but signs that clinically mimicked a recurrence. Compared with annual PET, the annual cost of blood tests every 3 to 6 months per patient saved approximately 77% ∼ 88% in expenses. CONCLUSIONS: The plasma EBV DNA assay correctly predicted all NPC recurrences, and PET had high capacity to localize potential lesion sites. The authors concluded that applying the strategy of EBV DNA screening followed by PET scanning may guide appropriate further treatment planning in a cost-effective manner. Cancer 2011;. © 2011 American Cancer Society. [ABSTRACT FROM AUTHOR]

Background: The authors investigated the clinical implication of plasma Epstein-Barr virus (EBV) DNA assay and (18) F-fluoro-2-deoxy-D-glucose ((18) F-FDG) positron emission tomography (PET) in the detection of recurrent nasopharyngeal carcinoma (NPC)., Methods: Two hundred forty-five patients with NPC who had previously received treatment and were in a state of remission were monitored prospectively using a plasma EBV DNA assay every 3 to 6 months. (18) F-FDG PET studies were obtained when abnormal EBV DNA or clinically suggestive signs of recurrence were noted., Results: Thirty-six of 245 patients (14.7%) patients had abnormal EBV DNA tests and underwent PET scans. In the remaining 209 patients, 3658 blood tests were negative. PET scans also were obtained in 5 patients who had undetectable EBV DNA levels but signs that were clinically suggestive of disease recurrence. Subsequent analyses focused on 41 patients who had PET studies. In lesion-based analyses, the sensitivity, specificity, and accuracy of PET by visual interpretation were 81.8%, 77.1%, and 79.2%, respectively, for all 125 lesions. In patient-based analyses, the accuracy of PET by visual interpretation was 51.2%. All 36 patients who had detectable plasma levels of EBV DNA had demonstrable NPC recurrences, whereas no recurrences were noted in 5 patients who had undetectable EBV DNA levels but signs that clinically mimicked a recurrence. Compared with annual PET, the annual cost of blood tests every 3 to 6 months per patient saved approximately 77% ∼ 88% in expenses., Conclusions: The plasma EBV DNA assay correctly predicted all NPC recurrences, and PET had high capacity to localize potential lesion sites. The authors concluded that applying the strategy of EBV DNA screening followed by PET scanning may guide appropriate further treatment planning in a cost-effective manner., (Copyright © 2011 American Cancer Society.)