Changsha, China
Changsha, China

Hunan University , located in Changsha, Hunan province, is one of the oldest and most important national universities in China. Wikipedia.

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An intelligent and information multi-vehicle collaboratively operating municipal refuse collection and transfer system and method are provided. The system comprises an automated system with multiple-degree of freedom intelligent dustbin grabbing, an operating system with two types of refuse vehicles collaborating, a multi-vehicle collaborative operation information system, and a fixed-point refuse collection operation confirmation and remote monitoring information management system for coordinating overall operation of the systems. The automated system with multiple-degree of freedom intelligent dustbin grabbing system is used for the refuse vehicles to automatically collect dustbins; the operating system with two types of refuse vehicles collaborating comprises a plurality of small- and medium-sized refuse vehicles and large capacity refuse vehicles. The small- and medium-sized refuse vehicles collect refuse in the dustbins according to multi-vehicle collaborative operation information with the support of the multi-vehicle collaborative operation information system, and the large capacity refuse vehicles are used to dock with the collected refuse and transport the refuse out of town with the support of the multi-vehicle collaborative operation information system. The method is the implementation of the above system. The system and method have good operability and high degree of intelligence and provide good results of refuse disposal.

Hunan University and Changsha Boli Electrical Corporation | Date: 2014-09-15

A steady state control method for a three-phase double-mode inverter. Off-grid steady state control is composed of outer loop power droop control, voltage feed-forward quasi-resonant control, and inner current loop dead-beat control. Therefore, the response speed of the inverter is raised, and the influence caused by the load fluctuation of a micro-grid is inhibited. Based on the off-grid steady state control, grid-connected steady state control introduces phase lead control to the power droop control. Therefore, the output voltage of the inverter is always slightly ahead of the power grid voltage, which avoids the energy pour backward phenomenon of the inverter due to a phase error, and realizes stable and reliable running in the grid-connected mode.

Agency: Cordis | Branch: FP7 | Program: CP-FP-SICA | Phase: HEALTH.2010.1.1-3 | Award Amount: 4.87M | Year: 2011

Protein glycosylation is a post-translational phenomenon that is involved in most physiological and disease processes including cancer. Most of the known cancer-associated glycobiomarkers were discovered individually using liquid chromatography and mass spectroscopy. Though valuable, there is room for improvement in these approaches for the discovery phase. There is also a critical need for innovative, rapid, and high-throughput (HTP) technologies that will translate the discovery of cancer-associated glycobiomarkers from basic science to clinical application. The GlycoHIT consortium brings a highly experienced, innovative and interdisciplinary team of researchers from Europe, China and USA representing academia, industry and clinical fields to significantly enhance some of the existing glycoanalytical technologies and to advance novel HTP glycoanalytical technologies beyond current state of the art. Microchip technology and novel partitioning methods will be exploited for nanoscale HTP separations of serum glycoproteins for analysis by HPLC or LCMS. In parallel, lectin array technology will be radically improved by the innovative use of recombinant human lectins and lectin mimics derived by screening large phage displayed combinatorial libraries. Aptamer libraries will be exploited for identification of lectin mimics and development of a glycosignature platform Compatibility of the lectin/lectin mimic array technologies with novel label-free biosensors will be explored. Newly-developed technologies will be validated by analysis of serum samples from a variety of cancer patient cohorts and will be supported throughout by experimental interaction analysis, complex structural modelling and informatics. Effective project management, commercially-aware intellectual property management and targeted dissemination activities supplement the core science and ensure maximum impact for the project.

Fang X.,CAS Beijing National Laboratory for Molecular | Tan W.,University of Florida | Tan W.,Hunan University
Accounts of Chemical Research | Year: 2010

Molecular medicine is an emerging field focused on understanding the molecular basis of diseases and translating this information into strategies for diagnosis and therapy. This approach could lead to personalized medical treatments. Currently, our ability to understand human diseases at the molecular level is limited by the lack of molecular tools to identify and characterize the distinct molecular features of the disease state, especially for diseases such as cancer. Among the new tools being developed by researchers including chemists, engineers, and other scientists is a new class of nucleic acid probes called aptamers, which are ssDNA/RNA molecules selected to target a wide range of molecules and even cells. In this Account, we will focus on the use of aptamers, generated from cell-based selections, as a novel molecular tool for cancer research. Cancers originate from mutations of human genes. These genetic alterations result in molecular changes to diseased cells, which, in turn, lead to changes in cell morphology and physiology. For decades, clinicians have diagnosed cancers primarily based on the morphology of tumor cells or tissues. However, this method does not always give an accurate diagnosis and does not allow clinicians to effectively assess the complex molecular alterations that are predictive of cancer progression. As genomics and proteomics do not yet allow a full access to this molecular knowledge, aptamer probes represent one effective and practical avenue toward this goal. One special feature of aptamers is that we can isolate them by selection against cancer cells without prior knowledge of the number and arrangement of proteins on the cellular surface. These probes can identify molecular differences between normal and tumor cells and can discriminate among tumor cells of different classifications, at different disease stages, or from different patients. This Account summarizes our recent efforts to develop aptamers through cell-SELEX for the study of cancer and apply those aptamers in cancer diagnosis and therapy. We first discuss how we select aptamers against live cancer cells. We then describe uses of these aptamers. Aptamers can serve as agents for molecular profiling of spedfic cancer types. They can also be used to modify therapeutic reagents to develop targeted cancer therapies. Aptamers are also aiding the discovery of new cancer biomarkers through the recognition of membrane protdn targets. Importantly, we demonstrate how molecular assemblies can integrate the properties of aptamers and, for example, nanoparticles or microfluidic devices, to improve cancer cell enrichment, detection and therapy. Figure Presented. © 2010 American Chemical Society.

Yuan L.,Hunan University | Lin W.,Hunan University | Zheng K.,Hunan University | He L.,Hunan University | Huang W.,Hunan University
Chemical Society Reviews | Year: 2013

The long wavelength (far-red to NIR) analyte-responsive fluorescent probes are advantageous for in vivo bioimaging because of minimum photo-damage to biological samples, deep tissue penetration, and minimum interference from background auto-fluorescence by biomolecules in the living systems. Thus, great interest in the development of new long wavelength analyte-responsive fluorescent probes has emerged in recent years. This review highlights the advances in the development of far-red to NIR fluorescent probes since 2000, and the probes are classified according to their organic dye platforms into various categories, including cyanines, rhodamine analogues, BODIPYs, squaraines, and other types (240 references). © The Royal Society of Chemistry 2013.

Wang K.,Hunan University
The Analyst | Year: 2013

Living cell studies can offer tremendous opportunities for biological and disease studies. Due to their high sensitivity and selectivity, minimum interference with living biological systems, ease of design and synthesis, fluorescent nucleic acid probes (FNAPs) have been widely used in living cell studies, such as for intracellular detection, cell detection, and cell-to-cell communication. Here, we review the general requirements and the recent developments in FNAPs for living cell studies. We broadly classify these designs as hybridization probes and aptamer probes. For hybridization probes, we describe recently developed designs, such as nanomaterial-based and amplification-based hybridization probes. For aptamer probes, we discuss four general paradigms that have appeared most frequently in the literature: nanomaterial-based, nanomachine-based, cell surface-anchored and activatable aptamer probe designs in vivo. FNAPs promise to open up new and exciting opportunities in biological marks detection for a wide range of biological and medical applications.

Yu X.,Hunan University | Lu B.,Hunan University | Xu Z.,Hunan University
Advanced Materials | Year: 2014

Nanohoneycomb-like strongly coupled CoMoO4-3D graphene hybird electrodes are synthesized for supercapacitors which exhibit excellent specific capacitance and superior long-term cycle stability. The supercapacitor device can power a 5 mm-diameter LED efficiently for more than 3 min with a charging time of only 2 s, and shows high energy densities and good cycle stability. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Yuan L.,Hunan University | Lin W.,Hunan University | Zheng K.,Hunan University | Zhu S.,Hunan University
Accounts of Chemical Research | Year: 2013

Fluorescence imaging has emerged as a powerful tool for monitoring biomolecules within the context of living systems with high spatial and temporal resolution. Researchers have constructed a large number of synthetic intensity-based fluorescent probes for bio-imaging. However, intensity-based fluorescent probes have some limitations: variations in probe concentration, probe environment, and excitation intensity may influence the fluorescence intensity measurements. In principle, the use of ratiometric fluorescent probes can alleviate this shortcoming. Förster resonance energy transfer (FRET) is one of the most widely used sensing mechanisms for ratiometric fluorescent probes. However, the development of synthetic FRET probes with favorable photophysical properties that are also suitable for biological imaging applications remains challenging.In this Account, we review the rational design and biological applications of synthetic FRET probes, focusing primarily on studies from our laboratory. To construct useful FRET probes, it is a pre-requisite to develop a FRET platform with favorable photophysical properties. The design criteria of a FRET platform include (1) well-resolved absorption spectra of the donor and acceptor, (2) well-separated emission spectra of the donor and acceptor, (3) donors and acceptors with comparable brightness, (4) rigid linkers, and (5) near-perfect efficiency in energy transfer.With an efficient FRET platform in hand, it is then necessary to modulate the donor-acceptor distance or spectral overlap integral in an analyte-dependent fashion for development of FRET probes. Herein, we emphasize our most recent progress on the development of FRET probes by spectral overlap integral, in particular by changing the molar absorption coefficient of the donor dyes such as rhodamine dyes, which undergo unique changes in the absorption profiles during the ring-opening and -closing processes. Although partial success has been obtained in design of first-generation rhodamine-based FRET probes via modulation of acceptor molar absorption coefficient, further improvements in terms of versatility, sensitivity, and synthetic accessibility are required. To address these issues with the first-generation rhodamine-based FRET probes, we have proposed a strategy for the design of second-generation probes. As a demonstration, we have developed FRET imaging probes for diverse targets including Cu2+, NO, HOCl, cysteine, and H2O 2. This discussion of the methods for successfully designing synthetic FRET probes underscores the rational basis for further development of new FRET probes as a molecular toolbox for probing and manipulating a wide variety of biomolecules in living systems. © 2013 American Chemical Society.

Herein, we demonstrated a new optical microscopy method to selectively image small-size gold nanoparticles (GNPs) inside noisy living cells through determination of the difference image between the probe beam (illuminated at the resonance wavelength of GNPs, 532 nm) and the reference beam (illuminated at 473 nm). From computer simulation and single-particle imaging experiments, we demonstrated that GNPs with a diameter of 45 nm could be selectively imaged in the GNPs/cell lysates mixture and inside living cells by dual-wavelength difference (DWD) imaging. The diffusion dynamics of nucleic acids functionalized GNPs on cell membranes and the internalization kinetics of these GNPs by living cells were explored with this method. Our real-time tracking experiments showed that statistically 80% of GNPs were under restricted diffusion on the cell membrane. The cell cytoskeleton fence effect, as observed in the single-particle tracking experiments, may be one of the main factors for the restricted diffusion mode.

We present here a highly selective and sensitive label-free method to detect Hg(2+) ions in aqueous solution by using DNA molecular machine-based fluorescent Ag nanoclusters (AgNCs). This mechanism is based on the Hg(2+) ions triggering machine-like operations of DNA and the "product" of the machine being used to stabilize fluorescent AgNCs. In this method, a tailored DNA, containing a sequence for Hg(2+) ions recognition, a sequence-specific nicking site for Nb BbvC I and a sequence complementary to the DNA as a template for the synthesis of fluorescent AgNCs, was firstly designed. In the presence of Hg(2+) ions, the machine's function operations were triggered. A series of machine-like operations, including replication, scission, and displacement then occurred with the addition of polymerase/dNTPs/Nb BbvC I, which manufactured lots of "product" DNA. The "product" DNA could act as a template for the preparation of fluorescent AgNCs. Thus the fluorescence of the AgNCs could be used as a signal transduction of this DNA machine, which was related to the concentration of the Hg(2+) ions. The repeated synthesis of the "product" and its template effect for AgNCs synthesis led to signal amplification in the assay of Hg(2+) ions. A linear response to the concentration of Hg(2+) ions was observed in the range from 0.08 nM to 20 nM and a detection limit of 0.08 nM was obtained. By contrast, the operation of the machine could not be executed in an Hg(2+) ion-free system. Moreover, the detection was not only label-free but also specific for Hg(2+) ions without being affected by other metal ions.

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