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Open access

Yun-Wei Zhang, Yun-Zhuan Zhou, Hai-Bo Lu, Deng-Yu Zheng and Yan-Hua Huang

Abstract

Sucrose phosphate synthase (SPS) is a key enzyme catalyzing sucrose metabolism in plants. In this study, we isolated the SPS cDNA from Saccharum spontaneum and designated as SsSPS (GenBank accession no. MF398541). The full-length of SsSPS cDNA was 4153-bp with an opening reading frame (ORF) of 3132 nucleotides, which encoded a 1043-amino acid protein. The nucleotide sequences alignment showed that it had 98%, 97% and 87% homology with S. officinarum, Setaria italica and Lolium perenne, respectively. Moreover, the SsSPS was detected to express in leaf and stem tissues of S. spontaneum and exhibited a predominant expression in the stem tissue. However, there was no significant difference in the expression level of SsSPS between young leaves and mature ones. Additionally, we generated transgenic S. spontaneum using Agrobacterium-mediated transformation. Our data will provide a valuable foundation for further study of the potential role of SPS in plants.

Open access

Wei Song, Huai-yuan Liu, Bin Xiang, Hong Hu, Cheng-jiang Wang and Ling-yun Wan

Open access

Yun Wei, Ying Yu, Lifeng Xu, Wei Huang, Jianhua Guo, Ying Wan and Jinde Cao

Abstract

Vehicle emission calculation is critical for evaluating motor vehicle related environmental protection policies. Currently, many studies calculate vehicle emissions from integrating the microscopic traffic simulation model and the vehicle emission model. However, conventionally vehicle emission models are presented as a stand-alone software, requiring a laborious processing of the simulated second-by-second vehicle activity data. This is inefficient, in particular, when multiple runs of vehicle emission calculations are needed. Therefore, an integrated vehicle emission computation system is proposed around a microscopic traffic simulation model. In doing so, the relational database technique is used to store the simulated traffic activity data, and these data are used in emission computation through a built-in emission computation module developed based on the IVE model. In order to ensure the validity of the simulated vehicle activity data, the simulation model is calibrated using the genetic algorithm. The proposed system was implemented for a central urban region of Nanjing city. Hourly vehicle emissions of three types of vehicles were computed using the proposed system for the afternoon peak period, and the results were compared with those computed directly from the IVE software with a trivial difference in the results from the proposed system and the IVE software, indicating the validity of the proposed system. In addition, it was found for the study region that passenger cars are critical for controlling CO, buses are critical for controlling CO and VOC, and trucks are critical for controlling NOx and CO2. Future work is to test the proposed system in more traffic management and control strategies, and more vehicle emission models are to be incorporated in the system.

Open access

Wei Guo, Jie Zhang, Jing-yun Li, Yue Ma and Sheng-hui Cui

Abstract

Objective A prospective study was conducted in a tertiary care center to identify the risk factors of ventilator associated pneumonia (VAP) through phenotypic and molecular biological methods.

Methods The patients who were mechanically ventilated in the respiratory intensive care unit (RICU) and the neurological internal intensive care unit (NICU) were enrolled in our study, and samples were collected from the lower respiratory tract, oropharynx and stomach. Other samples, including the environmental air, swabs of nurses’ hands, subglottic secretion and ventilator circuit, were also collected. Microorganisms in the collected samples were recovered and identified at species level by biochemical detection. Genetic relationship of dominant species was further characterized by pulsed field gel electrophoresis (PFGE).

Results Out of 48 enrolled patients, 22 cases developed VAP and bacterial cultures were recovered from the lower respiratory tract samples of 14 cases. The average hospitalization time with VAP was significantly longer than that of patients without VAP (P < 0.05). Among the recovered bacteria cultures, multidrug-resistant Pseudomonas aeruginosa and Stenotrophomonas maltophilia were dominant. It was more likely that subglottic secretion and gastric juice samples contained the same isolates as recovered in the lower respiratory tract by PFGE analysis.

Conclusions Mechanical ventilation in RICU and NICU was a high risk factor for VAP development. Special emphasis of VAP prophylaxis should be paid on subglottic secretion and gastric juice reflux.

Open access

Yun Gao, Mohammad Reza Farahani and Wei Gao

Abstract

In this article, we propose an ontology learning algorithm for ontology similarity measure and ontology mapping in view of distance function learning techniques. Using the distance computation formulation, all the pairs of ontology vertices are mapped into real numbers which express the distance of their corresponding vectors. The more distance between two vertices, the smaller similarity between their corresponding concepts. The stabilities of our learning algorithm are defined and several bounds are yielded via stability assumptions. The simulation experimental conclusions show that the new proposed ontology algorithm has high efficiency and accuracy in ontology similarity measure and ontology mapping in certain engineering applications.

Open access

Ninga Sun, Ying-chaoa Zhang, Wei-guoa Zhang, En-lua Cheng and Yun-ping

Abstract

In order to effectively solve condensation and icing problems of radiosonde in low-temperature environment at high altitude, humidity sensor heated automatic alternately to remove pollution and improve the measurement accuracy. Heat experiments obtained the curve of rising temperature and responsible time on heated twin humidity sensor in normal temperature and pressure, by expanded responsible curve to obtain heated model of twin heated humidity sensor and by the analysis of heating model, use DMC and PID control for heating respectively. Simulation results show that the DMC control meets the practical requirements of measure at high altitude.

Open access

Yu Dai, Quan-yang Ma, Xiao-hua Li, Xi Zhang, Fa-ping Hu, Yun Zhang and Wei-dong Xie

Abstract

In this paper, crushability of foundry sand particles was studied. Three kinds of in-service silica sands in foundry enterprises selected as the study object, and foundry sand particles were subjected to mechanical load and thermal load during service were analyzed. A set of methods for simulating mechanical load and thermal load by milling and thermal-cold cycling were designed and researched, which were used to characterize the crushability for silica sand particles, the microstructure was observed by SEM. According to the user’s experience in actual application, the crushability of Sand C was the best and then Sand B, the last Sand A. The results indicated that mechanical load, thermal load and thermal-mechanical load can all be used to characterize the crushability of foundry sand particles. Microscopic appearances can qualitatively characterize the crushability of foundry sand particles to a certain extent, combining with the additions and cracks which are observed on the surface.

Open access

Xiao-Dong Zhang, Yi-Fang Feng, Xu Zhang, Mi Tian, Tao Wu, Peng-Fei Ye, Wei Zhang, Yue-Yun Ding, Zong-Jun Yin and Ming-Xing Chu

Abstract

To justify the function of miRNAs in reproductive regulation in swine, the expression of miR-145, miR-429 and their related genes were studied in reproductive tissues of sows. Wannan black pig and Yorkshire pigs with extremely high (n=6) and low (n=6) litter size were sampled, and real-time quantitative PCR (qPCR) was performed on tissue samples from ovaries, uterus, oviduct, hypothalamus, and pituitary. The results indicated that miR-145, miR-429, and zinc finger E-box binding homeobox 1 gene (ZEB1) were expressed significantly different in Wannan black pig and Yorkshire pigs. In pigs with different fecundity, miR-145 in the uterus was expressed significantly lower in pigs with high litter size, than in pigs with low litter size. The miR-429 expression in the oviduct and pituitary of pigs with high litter size was significantly higher compared with tissues sampled from pigs with low litter size. The ZEB1 expression in the pituitary was lower in pigs with high litter size in comparison to pigs with low litter size, while luteinizing hormone beta subunit (LHβ) showed the opposite pattern of expression. In conclusion, miR-145 and miR-429 were differently expressed in pigs with high and low litter size and might have a role in affecting litter size of sows.

Open access

Chun Xie, Yi-Xuan Hou, Yu-Ting Zhao, Xue-Hui Cai, Cai-Ying Li, Pei-Feng Li, Yun-Zhang Li, Xue Su, Xiu-Wei Yue, Shu-Jie Wang, Yong-Gang Liu, Wei-Jun Yang, Cong-Li Yuan, Li Cu, Xiu-Guo Hua and Zhi-Biao Yang

Abstract

Five pathogen-free miniature pigs (minipigs) were infected with the virulent strain SH08 of Streptococcus suis 2 (SS2) by intramuscular injection. The pigs died consecutively within 72 h after the challenge. An additional five non-infected pigs were euthanised and used as controls. Microstructural observations showed that degeneration, bleeding, congestion, cellular necrosis, and an increase in inflammatory cells were present in all organs and tissues except the brain. Ultrastructural observations revealed mitochondrial vacuolation and malformed or missing cristae, indicating that infection of minipigs with strain SH08 of SS2 can lead to extensive lesions in major internal organs and tissues. The findings also demonstrated that the minipig is a useful model for the study of SS2 infection.

Open access

Ming-hui Li, Yao Xie, Yao Lu, Guo-hua Qiu, Lu Zhang, Ge Shen, Li-wei Zhuang, Ju-long Hu, Jian-ping Dong, Cai-qin Mu, Lei-ping Hu, Li-jun Chen, Xing-hong Li, Min Yang, Yun-zhong Wu, Hui Zhao, Shu-jing Song, Jun Cheng and Dao-zhen Xu

Abstract

Objective To investigate the effects of individualised treatment with peginterferon alpha-2a (40 kD) plus ribavirin in Chinese patients with CHC.

Methods Total of 297 consecutive Chinese patients were enrolled, including 250 naïve cases and 47 cases who were previously treated. Treatment duration was determined according to viral genotypes, prior treatment history and viral responses at week 4, 12 and 24.

Results Totally, 235 patients (79.1%) completed treatment and 186 (87.3%) achieved SVR. And 219 out of 289 (75.8%) patients achieved HCV RNA negative at week 4 (RVR) and 259 of 276 (93.8%) at week 12. Among the 164 patients with RVR who completed follow-up, 158 (96.3%) achieved SVR. Patients with RVR had lower baseline viral loads than patients without RVR (P = 0.034). The positive predictive value (PPV) of RVR for SVR was 90.7% (OR 2.10 vs. non-RVR, 95% CI: 0.50 - 8.7). Similar outcomes were observed among patients with HCV undetectable at week 12.

Conclusions Complete viral suppression by week 4 is associated with a high rate of treatment success in treatment naïve and experienced patients receiving individualized CHC therapy.