Capital Normal University

About: Capital Normal University is a education organization based out in Beijing, China. It is known for research contribution in the topics: Terahertz radiation & Quantum entanglement. The organization has 11441 authors who have published 11988 publications receiving 159071 citations. The organization is also known as: Shǒudū Shīfàn Dàxué.

Label-free fluorescent detection of ions, proteins, and small molecules using structure-switching aptamers, SYBR Gold, and exonuclease I.

Abstract: We have demonstrated a label-free sensing strategy employing structure-switching aptamers (SSAs), SYBR Gold, and exonuclease I to detect a broad range of targets including inorganic ions, proteins, and small molecules. This nearly universal biosensor approach is based on the observation that SSAs at binding state with their targets, which fold into secondary structures such as quadruplex structure or Y shape structure, show more resistance to nuclease digestion than SSAs at unfolded states. The amount of aptamer left after nuclease reaction is proportional to the concentrations of the targets and in turn is proportional to the fluorescence intensities from SYBR Gold that can only stain nucleic acids but not their digestion products, nucleoside monophosphates (dNMPs). Fluorescent assays employing this mechanism for the detection of potassium ion (K+) are sensitive, selective, and convenient. Twenty μM K+ is readily detected even at the presence of a 500-fold excess of Na+. Likewise, we have generalized the...

Monodispersed Gold Nanorod-Embedded Silica Particles as Novel Raman Labels for Biosensing†

Abstract: Biocompatible, photostable, and multiplexing-compatible surface-enhanced Raman spectroscopic tagging materials have been developed that are composed of gold nanorod (GNR)-embedded silica particles and organic Raman labels. GNR-embedded silica particles were prepared with different surface coverage by the assembly of GNRs on silica particles based on an electrostatic interaction and subsequent coating of silica with controllable thickness. This method allows the incorporation of various organic Raman labels to generate intense surface-enhanced Raman scattering (SERS) spectra. Furthermore, SERS-active particles are demonstrated as novel Raman tags for immunoassay. The results suggest SERS tags can be used for multiplex and ultrasensitive detection of biomolecules.

Geochemical significance of a garnet lherzolite from the Dahongshan kimberlite, Yangtze Craton, southern China

Abstract: The Dahongshan kimberlite field in Hubei Province, China, is situated in the northern margin of the Proterozoic Yangtze Craton. The kimberlites erupted in the Paleozoic (ca. 326 Ma), some of which are associated with barren lamproites. An unusually fresh garnet lherzolite collected from this kimberlite field provides an opportunity to directly study the nature of the Paleozoic lithospheric mantle beneath the Yangtze Craton. The lherzolite is moderately depleted in major element compositions (2.66wt% Al2O3, 2.82wt% CaO, and 90.9 Mg#), with a forsterite content in olivine around 90.5%. The rare earth element characteristics of the whole rock [(La/Sm)N = 13 and (Eu/Yb)N = 0.48] and of the constituent minerals such as clinopyroxene [(La/Yb)N = 61] reveal that at least two processes were recorded in the lherzolite: depletion followed by enrichment. Depletion process was derived from low degree of partial melting, as demonstrated by relatively high NiO contents (0.50%) in olivines and PPGE-enriched mantle-normalized PGE pattern of the whole rock. The enrichments in LREE and LILE are attributed to melt infiltration that must be an event prior to the kimberlite eruption as constrained by trace element and Sr-Nd isotopic data. The Rb-Sr and Sm-Nd data constrained an age of about 510 Ma, which is much older than the age of kimberlite eruption, but consistent with the eruption time of diamond-bearing lamproites on the centre of the Craton. The stable Gt-Opx-Cpx mineral assemblage gives a T-P estimation of 1042°C and 34 kbar, corresponding to 110 km depth, well within the graphite stability field. The geotherm inferred from this lherzolite was much higher than the typical cratonic geotherm (40 mW/m2), but still lower than the oceanic geotherm. Thus, our study and previous data demonstrate that the lithospheric mantle beneath the Yangtze craton was less depleted and was hotter in Paleozoic than the lithospheric mantle beneath typical old Cratons, i.e., the Kaapvaal, the Siberia, and the North China.

A molecular pathway for CO₂ response in Arabidopsis guard cells.

Abstract: Increasing carbon dioxide (CO₂) levels in the atmosphere have caused global metabolic changes in diverse plant species. CO₂ is not only a carbon donor for photosynthesis but also an environmental signal that regulates stomatal movements and thereby controls plant-water relationships and carbon metabolism. However, the mechanism underlying CO₂ sensing in stomatal guard cells remains unclear. Here we report characterization of Arabidopsis RESISTANT TO HIGH CO₂ (RHC1), a MATE-type transporter that links elevated CO₂ concentration to repression of HT1, a protein kinase that negatively regulates CO₂-induced stomatal closing. We also show that HT1 phosphorylates and inactivates OST1, a kinase which is essential for the activation of the SLAC1 anion channel and stomatal closing. Combining genetic, biochemical and electrophysiological evidence, we reconstituted the molecular relay from CO₂ to SLAC1 activation, thus establishing a core pathway for CO₂ signalling in plant guard cells.

Edge-Oriented Computing Paradigms: A Survey on Architecture Design and System Management

Abstract: While cloud computing has brought paradigm shifts to computing services, researchers and developers have also found some problems inherent to its nature such as bandwidth bottleneck, communication overhead, and location blindness. The concept of fog/edge computing is therefore coined to extend the services from the core in cloud data centers to the edge of the network. In recent years, many systems are proposed to better serve ubiquitous smart devices closer to the user. This article provides a complete and up-to-date review of edge-oriented computing systems by encapsulating relevant proposals on their architecture features, management approaches, and design objectives.