13 research outputs found
Horizontal structure of convergent wind shear associated with sporadic E layers over East Asia
At present, the main detection instruments for observing sporadic E (Es) layers are ground-based radars, dense networks of ground-based global navigation satellite system (GNSS) receivers, and GNSS radio occultation, but they cannot capture the whole picture of the horizontal structure of Es layers. This study employs the Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension model (WACCM-X 2.1) to derive the horizontal structure of the ion convergence region (HSICR) to explore the shapes of the large-scale Es layers over East Asia for the period from June 1 to August 31, 2008. The simulation produced the various shapes of the HSICRs elongated in the northwestâsoutheast, northeastâsouthwest, or composed of individual small patches. The close connection between Es layer critical frequency (foEs) and vertical ion convergence indicates that the HSICR is a good candidate for revealing and explaining the horizontal structure of the large-scale Es layers
Dual-Target Electrochemical Biosensing Based on DNA Structural Switching on Gold Nanoparticle-Decorated MoS<sub>2</sub> Nanosheets
A MoS<sub>2</sub>-based electrochemical
aptasensor has been developed for the simultaneous detection of thrombin
and adenosine triphosphate (ATP) based on gold nanoparticles-decorated
MoS<sub>2</sub> (AuNPsâMoS<sub>2</sub>) nanocomposites. Two
different aptamer probes labeled with redox tags were simultaneously
immobilized on an AuNPsâMoS<sub>2</sub> film modified electrode
via AuâS bonds. The aptamers presented structural switches
with the addition of target molecules (thrombin and ATP), resulting
in methylene blue (MB) far from or ferrocene (Fc) close to the electrode
surface. Therefore, a dual signaling detection strategy was developed,
which featured both âsignal-onâ and âsignal-offâ
elements in the detection system because of the target-induced structure
switching. This proposed aptasensor could simultaneously determine
ATP and thrombin as low as 0.74 nM ATP and 0.0012 nM thrombin with
high selectivity, respectively. In addition, thrombin and ATP could
act as inputs to activate an AND logic gate
Luminescence properties of Tb3+-doped oxyfluoride scintillating glasses
Transparent oxyfluoride glasses doped with Tb3+ were prepared by melt quenching method. The transmittance spectra show the glasses have good transmittance in the visible spectrum region. The emission spectra under 376 nm light and X-ray excitations were recorded. Tb3+ doped oxyfluoride glasses show intense green emissions under both excitations. The optimum concentrations of Tb3+ ion are around 8 mol% and around 10 mol% under 376 nm light excitation and X-ray excitation, respectively. The lifetimes of 541 nm emission of oxyfluoride glasses doped with Tb3+ are in the range from 2.65 ms to 3.02 ms. The results indicate that Tb3+-doped oxyfluoride glasses could be an X-ray scintillating material suitable to X-ray detection for slow event. © 2013 Elsevier B.V
Centrosomal Nlp is an oncogenic protein that is gene-amplified in human tumors and causes spontaneous tumorigenesis in transgenic mice
Disruption of mitotic events contributes greatly to genomic instability and results in mutator phenotypes. Indeed, abnormalities of mitotic components are closely associated with malignant transformation and tumorigenesis. Here we show that ninein-like protein (Nlp), a recently identified BRCA1-associated centrosomal protein involved in microtubule nucleation and spindle formation, is an oncogenic protein. Nlp was found to be overexpressed in approximately 80% of human breast and lung carcinomas analyzed. In human lung cancers, this deregulated expression was associated with NLP gene amplification. Further analysis revealed that Nlp exhibited strong oncogenic properties; for example, it conferred to NIH3T3 rodent fibroblasts the capacity for anchorage-independent growth in vitro and tumor formation in nude mice. Consistent with these data, transgenic mice overexpressing Nlp displayed spontaneous tumorigenesis in the breast, ovary, and testicle within 60 weeks. In addition, Nlp overexpression induced more rapid onset of radiation-induced lymphoma. Furthermore, mouse embryonic fibroblasts (MEFs) derived from Nlp transgenic mice showed centrosome amplification, suggesting that Nlp overexpression mimics BRCA1 loss. These findings demonstrate that Nlp abnormalities may contribute to genomic instability and tumorigenesis and suggest that Nlp might serve as a potential biomarker for clinical diagnosis and therapeutic target