ABSTRACT
Self-assembled growth of blue-green-yellow-red InGaN quantum dots (QDs) on GaN templates using plasma-assisted molecular beam epitaxy were investigated. We concluded that growth conditions, including small N2 flow and high growth temperature are beneficial to the formation of InGaN QDs and improve the crystal quality. The lower In/Ga flux ratio and lower growth temperature are favorable for the formation of QDs of long emission wavelength. Moreover, the nitrogen modulation epitaxy method can extend the wavelength of QDs from green to red. As a result, visible light emissions from 460 nm to 622 nm have been achieved. Furthermore, a 505 nm green light-emitting diode (LED) based on InGaN/GaN MQDs was prepared. The LED has a low external quantum efficiency of 0.14% and shows an efficiency droop with increasing injection current. However, electroluminescence spectra exhibited a strong wavelength stability, with a negligible shift of less than 1.0 nm as injection current density increased from 8 A/cm2 to 160 A/cm2, owing to the screening of polarization-related electric field in QDs.
ABSTRACT
High Al-content AlGaN epilayers were grown on AlN template by using indium (In) surfactant with plasma-assisted molecular beam epitaxy (PA-MBE), and deep ultraviolet emission at 235 nm was obtained at room temperature. The effects and mechanisms of In-surfactant on the crystalline quality and optical properties of AlGaN were investigated. It was found that In-surfactant could facilitate two-dimensional AlGaN growth by reducing activation barrier for Al/Ga atoms to cross steps and effectively increasing the migration rate on the growth surface, and thus improve surface morphology and decrease defect density. The photoluminescence measurements revealed that the optical properties were remarkably improved by adopting In as surfactant, and phase separation was also effectively eliminated. Furthermore, the concentration of impurities including oxygen and silicon was decreased, which is attributed to higher defects formation energy for these impurities with In-surfactant assisted epitaxy growth.
ABSTRACT
As one of the most aggressive malignancies, non-small cell lung carcinoma (NSCLC) has high risks of death. It has been demonstrated that circRNAs accelerate NSCLC progression, but the underlying molecular mechanisms of circRNAs in NSCLC were still obscure. In the first place, the circRNA microarray of NSCLC was investigated in this study, and hsa_circ_0008003 (circ-0008003) was chosen as the research object. Then, it was unveiled that the expression of circ-0008003 examined via qRT-PCR was elevated in tumour tissues relative to the non-tumour tissues, which was associated with TNM stage and lymphatic metastasis in NSCLC. Additionally, the prognosis of NSCLC patients with high circ-0008003 level was poor. Besides, circ-0008003 silencing dampened the invasion and proliferation of NSCLC cells. Next, according to the mechanistic studies, circ-0008003 functioned as a ceRNA of ZNF281 in NSCLC by acting as the endogenous sponge for miR-488, which was proved to be a tumour suppressor in NSCLC. Additionally, ZNF281 overexpression and miR-488 suppression recovered the influences of repressed circ-0008003 on NSCLC cellular processes. It was validated in this research that circ-0008003 triggered tumour formation in NSCLC, which was adjusted via miR-488/ZNF281 axis, casting a novel light on the resultful target for treating NSCLC and predicting the prognosis.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , MicroRNAs , Carcinogenesis/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Cell Proliferation/genetics , Cell Transformation, Neoplastic , Humans , Lung Neoplasms/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Circular/genetics , Repressor ProteinsABSTRACT
In order to explore the correlation between the medicinal propertiesï¼efficacy and application in the same genetic relationshipï¼explain the scientific connotation of the medicinal properties and effects of traditional Chinese medicines(TCM)ï¼promote the academic development of the theory of traditional Chinese medicinesï¼and provide reference for the research and development of the traditional Chinese medicines of a same genus. In this paper, a literature study of ancient and modern works of Chinese herbal medicine was conducted to investigate the correlation between the properties, meridians tropism, efficacy and application of Alpinia officinarumï¼ A. katsumadaiï¼ Galangae Fructus and Alpinae Oxyphyllae Fructus, four kinds of Alpinia Chinese medicinesï¼The results showed that the similar properties of these four kinds of Alpinia Chinese medicines included that they were acrid, warm,and mainly getting into the spleen and stomach channels; the similar efficacies included that dispelling coldï¼relieving painï¼warming stomachï¼anti-nauseaï¼anti-diarrhealï¼reinforcing spleen to promote digestion and other effects; in application aspects, the similarities were that they were all mainly used in treatment of catching cold or spleen deficiency induced by abdominal painï¼vomitingï¼diarrhea,diet indigestion, etc. indicating that phylogenetic relationship was closely related with the herbal properties, efficacy and application. It is an effective way to exploreï¼collate and research traditional Chinese medicine by using plant phylogenetic relationships in exploring the internal relations and laws of TCM theoriesï¼material bases, pharmacological effects and clinical applications, also with a strong maneuverability to explain their scientific connotation.