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Li G.-Y.,National University of Defense Technology | Li X.-D.,National University of Defense Technology | Wang H.,National University of Defense Technology | Liu L.,Wuhan Mechanical Technology College
Applied Physics A: Materials Science and Processing | Year: 2010

In this communication, we report on the attempt to make full use of the off-gases from polycarbosilane-derived SiC preparation, and we successfully synthesized long SiC nanowires in large areas with Fe(NO3) 3 as catalyst. The nanowires have diameters of about 80-300 nm and lengths of millimeters, and they are identified as single crystals β-SiC along the 〈111〉 direction. The VLS mechanism was employed to interpret the nanowire growth. © 2009 Springer-Verlag. Source

Yan L.-R.,Wuhan General Hospital of Guangzhou Command | Wu Y.-B.,Wuhan Mechanical Technology College | Zeng X.-H.,Wuhan General Hospital of Guangzhou Command | Gao L.-C.,Wuhan General Hospital of Guangzhou Command
Frontiers in Human Neuroscience | Year: 2015

Parkinson’s disease (PD) is a neurodegenerative disorder affecting middle-aged and elderly people. PD can be viewed as “circuit disorder,” indicating that large scale cortico-subcortical pathways were involved in its pathophysiology. The brain network in an experimental context is emerging as an important biomarker in disease diagnosis and prognosis prediction. This context-dependent network for PD and the underling functional mechanism remains unclear. In this paper, the brain network profiles in 11 PD patients without dementia were studied and compared with 12 healthy controls. The functional magnetic resonance imaging (fMRI) data were acquired when the subjects were performing a pseudorandomized unimanual or bimanual finger-to-thumb movement task. The activation was detected and the network profiles were analyzed by psychophysiological interaction (PPI) toolbox. For the controls and PD patients, the motor areas including the primary motor and premotor areas, supplementary motor area, the cerebellum and parts of the frontal, temporal and parietal gyrus were activated. The right putamen exhibited significant control > PD activation and weaker activity during the bimanual movement relative to the unimanual movement in the control group. The decreased putamen modulation on some nucleus in basal ganglia, such as putamen, thalamus and caudate, and some cortical areas, such as cingulate, parietal, angular, frontal, temporal and occipital gyrus was detected in the bimanual movement condition relative to the unimanual movement condition. Between-group PPI difference was detected in cingulate gyrus, angular gyrus and precuneus (control > PD) and inferior frontal gyrus (PD > control). The deficient putamen activation and its enhanced connectivity with the frontal gyrus could be a correlate of impaired basal ganglia inhibition and frontal gyrus compensation to maintain the task performance during the motor programs of PD patients. © 2015 Yan, Wu, Zeng and Gao. Source

Dai N.,Huazhong University of Science and Technology | Xu B.,Huazhong University of Science and Technology | Xu B.,Wuhan Mechanical Technology College | Jiang Z.,Huazhong University of Science and Technology | And 5 more authors.
Optics Express | Year: 2010

The effect of Yb3+ concentration on the broadband emission intensity and peak wavelength shift in Yb/Bi ions co-doped silicate glasses is investigated. The optimal Bi2O3 concentration range is about 2.0-2.5mol% in 65SiO2-10Al2O3-25CaO matrix (SAC glasses). For Yb/Bi codoped SAC glasses, the maximum emission intensity excited by 980nm LD is ∼30 times and 1.5 times higher than that of single Bi-doped SAC glasses excited by 980nm and 808nm LD, respectively, the peak emission shows obvious red-shift from 1185 nm to 1235 nm band with the Yb2O3 concentration change from 0 to 3.0 mol%. For the same Yb2O3 concentration in SAC glasses, the measured fluorescence lifetime near 1020nm of single Yb3+-doped glasses is longer than that of Yb/Bi codoping glasses, which implyes the efficient energy transfer from Yb3+ to Bin+ in SAC glasses. The results indicate Yb2O3 can be induced into the bismuthdoped silicate glasses to enhance the emission intensity and control the peak wavelength. © 2010 Optical Society of America. Source

Zheng Y.,Huazhong University of Science and Technology | Huang C.,Huazhong University of Science and Technology | Cheng Z.,Wuhan Mechanical Technology College | Chen M.,Huazhong University of Science and Technology
Journal of Innovative Optical Health Sciences | Year: 2012

Background and aims: The spectral properties of enhanced green fluorescent protein (EGFP) used in current visualizable animal models for nasopharyngeal carcinoma (NPC) result in a limited imaging depth. Far-red fluorescent proteins have optimal spectral wavelengths that allow deep tissue penetration, thus are well-suited for the imaging of tumor growth and metastases in live animals. This study aims to establish an imageable animal model of NPC using far-red fluorescent proteins. Methods: Eukaryotic expression vectors of far-red fluorescent proteins, mLumin and Katushka S158A, were separately transfected into 5-8F NPC cells, and cell lines stably expressing the far-red fluorescent proteins were obtained. These cells were intraperitoneally or intravenously injected into mice, and their tumorigenic and metastatic potential were examined through fluorescence imaging. Finally, factors affecting their tumorigenic ability were further assessed through testing side population (SP) cells proportion by flow cytometry. Results: NPC cell line with high tumorigenicity and metastasis (5-8F-mL2) was screened out, which stably expressed far-red fluorescent protein. Intraperitoneal and intravenous injection of 5-8F-mL2 cells resulted in an abdomen metastasis model and a lung metastasis model. In addition, NPC cell line without tumorigenicity (5-8F-Katushka S158A) was screened out. The percentage of SP cells between 5-8F-mL2 and 5-8F-Katushka S158A was found different, suggesting that the SP cell proportion may play a key role in the determination of cell tumorigenic ability. Conclusion: We successfully established animal models for NPC with high tumorigenicity and metastasis using a super-bright far-red fluorescent protein. Owing to the super-brightness and excellent wavelength parameters, these models may be applied as useful tools for intuitive and efficient monitoring of tumor growth and metastasis, as well as assessing the efficacy of nasopharyngeal cancer drugs. © 2012 World Scientific Publishing Company. Source

Dai N.,Huazhong University of Science and Technology | Luan H.,Huazhong University of Science and Technology | Xu B.,Wuhan Mechanical Technology College | Yang L.,Huazhong University of Science and Technology | And 3 more authors.
Journal of Non-Crystalline Solids | Year: 2012

We have studied the effects of Si doping on the near infrared (NIR) luminescence observed in low Bi doped (0.1 mol%) glasses and the energy transfer from Yb3+ to Bi. The broadband near infrared can only be observed when Si is introduced in the Bi-doped glass. The origin of this fluorescence can be attributed to Bi ions at low valence. Efficient energy transfer from Yb 3+ to Bi NIR active ions is achieved by co-doping of Si. There is an increment of about ~ 29 times of the emission intensity from Bi-related active center as the Yb3+ concentration varies from 0 to 2.0 mol% and the amount of Si is 0.05 mol% under 980 nm excitation. The possible mechanism of energy transfer from Yb3+ to Bi is also discussed. © 2011 Elsevier B.V. All rights reserved. Source

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