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Dietary flavonoids show beneficial effects in the prevention of chronic diseases. However, flavonoid bioavailability is poor, probably due to their interaction with serum albumins. In the current work, the binding interactions of eight related flavonoids, sharing a similar core structure, with bovine serum albumin (BSA) were investigated by fluorescence spectroscopy. The binding affinities of the flavonoids with BSA were in the order hesperetin (KA=5.59 × 105)> quercetin (4.94 × 105) > naringenin (3.04 × 105) > isoquercitrin (4.66 × 104) > icariin (3.60 × 104) > rutin (1.65 × 104) > hesperidin (2.50 × 103) > naringin (8.70 × 102). The associations of specific structural components of the flavonoids with their binding properties to BSA were also explored and hydrophobicity, functional group substituents, steric hindrance effects and the spatial arrangements of substituents seem to be the key factors for the affinities of flavonoids towards BSA. The results from the current work contribute to a better understanding of the transport of flavonoids in plasma and helping predict their physiological functions based on their intrinsic structures.

Macroscopic network traffic state analysis is the premise of relieving urban traffic congestion. Computer simulations contribute to settle the complexity of the urban network traffic flow dynamics in traffic states research. In this paper, we make a simulation of urban network gridlock formation process for the study of the variability of vehicle densities. Based on the simulation results, we get there important conclusions about network vehicle densities and put forward the concept of the standard deviation of the number of vehicles on all links (SDVL). We also use a mathematic matrix analysis method to verify the conclusions. Then we show that there exist macroscopic fundamental diagrams (MFD) based on SDVL. We describe and explain the shape of the SDVL-MFD using simulation data. And an effective macroscopic traffic state analysis method is proposed on the basis of macroscopic fundamental relations of SDVL, which could provide decision support for signal control scheme optimization and traffic state forecasting.

Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid amplification method performed under isothermal conditions and has a high specificity and efficiency. We developed a LAMP assay targeting the 16S rRNA gene for rapid detection of Haemophilus parasuis. The results obtained from testing 31 H. parasuis strains and 28 other bacterial species strains showed that LAMP was as specific as, and more sensitive than, nested PCR. Fifty-five lung samples were collected from 55 healthy pigs. All the samples were negative for H. parasuis by bacterial isolation, nested PCR and LAMP, respectively. In addition, 122 lung samples were collected from 122 pigs with apparent respiratory problems. Sixty-five were positive by bacterial isolation. All the samples that were positive by bacterial isolation were also positive by nested PCR and LAMP. The LAMP assay demonstrated higher sensitivity than nested PCR, picking up 16 additional cases. The LAMP assay also gave a same result compared with the nested PCR when the two assays were used, respectively, to detect H. parasuis from samples obtained from experimentally infected pigs. We concluded that LAMP is a highly sensitive and reliable method for detection of H. parasuis infection.

A localization system for indoor mobile robots using ultrasonic net is presented in this paper. In positioning process, a triangle localization algorithm and an averaging filter method are introduced. After constructing an experimental platform and ultrasonic net, static and dynamic experiments are performed to acquire the accuracy of localization system. Then, positioning experiments for a moving robot are implemented with four different speeds. Integrated with all experiments, causes of positioning error are analyzed. As a result, the system is stable, reliable and easy to realize. It can meet the general requirement of localization for indoor mobile robots.

First, a cDNA library from Gloydius shedaoensis shedaoensis venom gland (GSSG) was constructed using SMART technique. The total RNA in a pair of GSSGs was separated and the mRNA was further isolated from it. The first-strand cDNA was synthesized through PowerScript(™) reverse transcriptase by a CDS III/3' PCR primer. A SMART IV(™) -oligonucleotide was used as the template for the synthesis of double-strand cDNA and amplified by long-distance polymerase chain reaction (LD-PCR). LD-PCR product was purified, digested, fractionated, and finally ligated to pDNR-LIB vector. The recombinant DNA was transformed into Escherichia coli DH10B. The titer of this library was 8 × 10(7) cfu/mL. Most inserts were1,000 bp with great recombination efficacy. 216 GSSG-cDNAs were randomly analyzed and obtained 211 expressed sequence tags (ESTs) in high quality. A total of 84 ESTs were known functional genes showing significant similarities to known function proteins, 29 ESTs were unknown functional genes showing significant similarities to unknown function proteins, and 98 ESTs were novel genes with no match in any database, which account for 39.8%, 13.7%, and 46.5% of obtained ESTs. We successfully constructed a cDNA library and characterized partial ESTs of GSSG, which provides a solid base for cloning and expressing target genes and studying the biological functions of target proteins from GSS.

Loop-mediated isothermal amplification (LAMP) is a novel nucleic acid amplification method performed under isothermal conditions and has a high specificity and efficiency. We developed a LAMP assay targeting the 16S rRNA gene for rapid detection of Haemophilus parasuis. The results obtained from testing 31 H. parasuis strains and 28 other bacterial species strains showed that LAMP was as specific as, and more sensitive than, nested PCR. Fifty-five lung samples were collected from 55 healthy pigs. All the samples were negative for H. parasuis by bacterial isolation, nested PCR and LAMP, respectively. In addition, 122 lung samples were collected from 122 pigs with apparent respiratory problems. Sixty-five were positive by bacterial isolation. All the samples that were positive by bacterial isolation were also positive by nested PCR and LAMP. The LAMP assay demonstrated higher sensitivity than nested PCR, picking up 16 additional cases. The LAMP assay also gave a same result compared with the nested PCR when the two assays were used, respectively, to detect H. parasuis from samples obtained from experimentally infected pigs. We concluded that LAMP is a highly sensitive and reliable method for detection of H. parasuis infection.