64 results on '"Xiao-Fen, Wang"'
Search Results
2. A Cloud-based IoMT Data Sharing Scheme with Conditional Anonymous Source Authentication.
- Author
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Yan-Ping Wang, Xiao-Fen Wang, Hong-Ning Dai, Xiaosong Zhang 0001, Yu Su, Muhammad Imran 0001, and Nidal Nasser
- Published
- 2022
- Full Text
- View/download PDF
3. Privacy-Preserving Data Collection for Mobile Phone Sensing Tasks.
- Author
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Yi-Ning Liu 0002, Yan-Ping Wang, Xiao-Fen Wang, Zhe Xia, and Jingfang Xu
- Published
- 2018
- Full Text
- View/download PDF
4. Privacy-preserving raw data collection without a trusted authority for IoT.
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Yi-Ning Liu 0002, Yan-Ping Wang, Xiao-Fen Wang, Zhe Xia, and Jingfang Xu
- Published
- 2019
- Full Text
- View/download PDF
5. Block-Level Message-Locked Encryption with Polynomial Commitment for IoT Data.
- Author
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Ke Huang 0002, Xiaosong Zhang 0001, and Xiao-Fen Wang
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- 2017
6. Competence of clinical teachers: A survey on perception of masters of nursing specialist postgraduates, their clinical teachers, and head nurses
- Author
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Xiao-fen Wang, Ling Zhao, Hong-juan Hu, Gao-wen Ou, and Li Liao
- Subjects
Clinical teachers ,Education, Nursing, Graduate ,Masters of nursing specialist ,Performance appraisal ,Nursing ,RT1-120 - Abstract
Objectives: To explore the current admittance situation of clinical teachers for masters of nursing specialist (MNS) postgraduates and to test the competence of clinical teachers in self-evaluation and other evaluations. Methods: In this cross-sectional study, using a random number table, we chose 80 MNS postgraduates under clinical practice, their clinical teachers, and head nurses each from six hospitals in Hunan and Guangdong. The participants were tested on the basis of the Clinical Teachers' Competence Inventory of MNS Postgraduates. The competences of clinical teachers were evaluated by the three groups of participants. Results: The aggregated scores of teacher competence as evaluated by the MNS postgraduates (181.33 ± 24.95) were lower than those assigned by both clinical teachers (190.75 ± 24.30) and their head nurses (198.53 ± 18.90), with significant differences in all dimensions except for clinical managing ability. The five highest rated items from all participants focused on the teachers' clinical nursing ability, and the five lowest rated items were mainly about their clinical research ability. Conclusion: The evaluation from MNS postgraduates is obviously lower than the self-evaluation of clinical teachers, and all participants are aware of the deficiency in research ability of the teachers. Thus, the admittance and examination of clinical teachers should be controlled strictly. Training should be carried out immediately to strengthen their comprehensive abilities, especially their research ability.
- Published
- 2017
- Full Text
- View/download PDF
7. The effects of fermentation and adsorption using lactic acid bacteria culture broth on the feed quality of rice straw
- Author
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Jing-jing LIU, Xiao-ping LIU, Ji-wei REN, Hong-yan ZHAO, Xu-feng YUAN, Xiao-fen WANG, Abdelfattah Z M Salem, and Zong-jun CUI
- Subjects
adsorption ,fermentation ,lactic acid bacteria culture broth ,rice straw ,Agriculture (General) ,S1-972 - Abstract
To improve the nutritional value and the palatability of air-dried rice straw, culture broth of the lactic acid bacteria community SFC-2 was used to examine the effects of two different treatments, fermentation and adsorption. Air-dried and chopped rice straw was treated with either fermentation for 30 d after adding 1.5 L nutrient solution (50 mL inocula L−1, 1.2×1012 CFU mL−1 inocula) kg−1 straw dry matter, or spraying a large amount of culture broth (1.5 L kg−1 straw dry matter, 1.5×1011 CFU mL−1 culture broth) on the straw and allowing it to adsorb for 30 min. The feed quality and aerobic stability of the resulting forage were examined. Both treatments improved the feed quality of rice straw, and adsorption was better than fermentation for preserving nutrients and improving digestibility, as evidenced by higher dry matter (DM) and crude protein (CP) concentrations, lower neutral detergent fiber (NDF), acid detergent fiber (ADF) and NH3-N concentrations, as well as higher lactic acid production and in vitro digestibility of DM (IVDMD). The aerobic stability of the adsorbed straw and the fermented straw was 392 and 480 h, respectively. After being exposed to air, chemical components and microbial community of the fermented straw were more stable than the adsorbed straw.
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- 2015
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8. Research on the Energy Hole Problem Based on Non-uniform Node Distribution for Wireless Sensor Networks.
- Author
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Tang Liu 0001, Jian Peng 0002, Xiao-fen Wang, Jin Yang, and Bing Guo
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- 2012
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9. Microbial Community Dynamics During Biogas Slurry and Cow Manure Compost
- Author
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Hong-yan ZHAO, Jie LI, Jing-jing LIU, Yu-cai LÜ, Xiao-fen WANG, and Zong-jun CUI
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biogas slurry fermentation compost ,denaturing gradient gel electrophoresis (DGGE) ,gene clone library ,maturity ,Agriculture (General) ,S1-972 - Abstract
This study evaluated the microbial community dynamics and maturation time of two compost systems: biogas slurry compost and cow manure compost, with the aim of evaluating the potential utility of a biogas slurry compost system. Denaturing gradient gel electrophoresis (DGGE), gene clone library, temperature, C/N ratio, and the germination index were employed for the investigation, cow manure compost was used as the control. Results showed that the basic strip and dominant strips of the DGGE bands for biogas slurry compost were similar to those of cow manure compost, but the brightness of the respective strips for each system were different. Shannon-Weaver indices of the two compost systems differed, possessing only 22% similarity in the primary and maturity stages of the compost process. Using bacterial 16S rRNA gene clone library analysis, 88 bacterial clones were detected. Further, 18 and 13 operational taxonomic units (OTUs) were present in biogas slurry and cow manure compost, respectively. The 18 OTUs of the biogas slurry compost belonged to nine bacterial genera, of which the dominant strains were Bacillus sp. and Carnobacterium sp.; the 13 OTUs of the cow manure compost belonged to eight bacterial genera, of which the dominant strains were Psychrobacter sp., Pseudomonas sp., and Clostridium sp. Results demonstrated that the duration of the thermophilic phase (more than 50°C) for biogas slurry compost was 8 d less than the according duration for cow manure compost, and the maturation times for biogas slurry and cow manure compost were 45 and 60 d, respectively. It is an effective biogas slurry assimilate technology by application of biogas slurry as nitrogen additives in the manufacture of organic fertilizer.
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- 2013
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10. Privacy-preserving raw data collection without a trusted authority for IoT
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Zhe Xia, Yining Liu, Jing-Fang Xu, Xiao-Fen Wang, and Yan-Ping Wang
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Scheme (programming language) ,Computer Networks and Communications ,business.industry ,Computer science ,Big data ,020206 networking & telecommunications ,02 engineering and technology ,Trusted authority ,Computer security ,computer.software_genre ,Privacy preserving ,Information sensitivity ,Order (business) ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Internet of Things ,business ,Raw data ,computer ,computer.programming_language - Abstract
With the rapid developments of IoT technologies, a large amount of real-time data is collected and shared, having important impacts on many applications, such as business advertisement and decision-making assistance. However, most users are unwilling to share their personal data directly to any third party for either academic research or commercial analysis because personal data contains private or sensitive information, such as economic status or living habits. Balancing the utility of big data and users’ privacy is a vital issue in academia and industry. In this paper, a privacy-preserving raw data collection scheme for IoT is proposed, in which the participant's data is collected and obfuscated with the other participants’ data within a group in order to mask the individual's privacy. Specifically, individual data is kept in its raw format to enhance its value for the data consumer, while no other users outside of the user herself know the source of the collected data. In addition, no trusted authority (TA) is needed in our proposed scheme, which is more suitable for real-world applications. Moreover, efficiency analysis is performed by simulation, and the result shows that our proposed scheme is practical for IoT systems.
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- 2019
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11. Competence of clinical teachers: A survey on perception of masters of nursing specialist postgraduates, their clinical teachers, and head nurses
- Author
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Ling Zhao, Hong-juan Hu, Li Liao, Xiao-fen Wang, and Gao-wen Ou
- Subjects
lcsh:RT1-120 ,Performance appraisal ,lcsh:Nursing ,030504 nursing ,business.industry ,Masters of nursing specialist ,media_common.quotation_subject ,education ,behavioral disciplines and activities ,03 medical and health sciences ,0302 clinical medicine ,Nursing ,Perception ,mental disorders ,Clinical teachers ,Medicine ,Original Article ,030212 general & internal medicine ,0305 other medical science ,business ,Education, Nursing, Graduate ,Competence (human resources) ,General Nursing ,media_common - Abstract
OBJECTIVES: To explore the current admittance situation of clinical teachers for masters of nursing specialist (MNS) postgraduates and to test the competence of clinical teachers in self-evaluation and other evaluations. METHODS: In this cross-sectional study, using a random number table, we chose 80 MNS postgraduates under clinical practice, their clinical teachers, and head nurses each from six hospitals in Hunan and Guangdong. The participants were tested on the basis of the Clinical Teachers' Competence Inventory of MNS Postgraduates. The competences of clinical teachers were evaluated by the three groups of participants. RESULTS: The aggregated scores of teacher competence as evaluated by the MNS postgraduates (181.33 ± 24.95) were lower than those assigned by both clinical teachers (190.75 ± 24.30) and their head nurses (198.53 ± 18.90), with significant differences in all dimensions except for clinical managing ability. The five highest rated items from all participants focused on the teachers' clinical nursing ability, and the five lowest rated items were mainly about their clinical research ability. CONCLUSION: The evaluation from MNS postgraduates is obviously lower than the self-evaluation of clinical teachers, and all participants are aware of the deficiency in research ability of the teachers. Thus, the admittance and examination of clinical teachers should be controlled strictly. Training should be carried out immediately to strengthen their comprehensive abilities, especially their research ability.
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- 2017
- Full Text
- View/download PDF
12. Research on modelling digital paper-cut preservation.
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Xiao-Fen Wang, Ying-Rui Liu, and Wen-Sheng Zhang
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- 2009
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13. Privacy-Preserving Data Collection for Mobile Phone Sensing Tasks
- Author
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Jing-Fang Xu, Zhe Xia, Yining Liu, Xiao-Fen Wang, and Yan-Ping Wang
- Subjects
Scheme (programming language) ,021110 strategic, defence & security studies ,Data collection ,Computer science ,0211 other engineering and technologies ,020206 networking & telecommunications ,02 engineering and technology ,Task (project management) ,Privacy preserving ,Mobile phone ,Human–computer interaction ,Obstacle ,0202 electrical engineering, electronic engineering, information engineering ,Statistical inference ,computer ,Anonymity ,computer.programming_language - Abstract
Lack of reliable data is a major obstacle in some research works because users are unwilling to provide their own private data to any third parties directly. Since statistical inference is aimed to analyze the overall data of a well-defined group rather than a specific individual, the paradigm of privacy-preserving data collection scheme is proposed recently, which can motivate users to contribute their data to research works. In this paper, two probable properties that promote the success of sensing tasks are analyzed, and a fog-assisted data collection scheme for mobile phone sensing tasks is proposed. Sensitive measurements are particularly protected by obfuscating them with the group values, which not only provides anonymity for participants but also enables accurate data for the task provider. Especially, the dynamic change of participants is also considered. Theoretical analysis shows that this method achieves the desired security goals, and experiments are performed to demonstrate the efficiency and feasibility.
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- 2018
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14. EBD-MLE: Enabling Block Dynamics under BL-MLE for Ubiquitous Data
- Author
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Xiao-Fen Wang, Ke Huang, Ruonan Zhang, Xiaojiang Du, and Xiaosong Zhang
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Metadata ,Computer science ,business.industry ,Server ,Distributed computing ,Data deduplication ,Access control ,Cloud computing ,business ,Encryption ,Cloud storage ,Block (data storage) - Abstract
Ubiquitous devices exchange and store data at all times and places under a pervasive environment. Using cloud storage to manage these data is cost-effective. However, ubiquitous data suffers from efficiency, privacy, and functionality issues. BL-MLE is an ideal tool for encrypting user data while enabling block-level deduplication for storage saving. BL-MLE or any other deduplication system cannot support block dynamics. The major difficulties are three-fold: (1) Integrity breaches; (2) Ownership management and access control; (3) Key updates. To address these, we propose a scheme called Enabling Block Dynamics under Block-Level Message-Locked Encryption (EBD-MLE) to enable full-block dynamics under BL-MLE for ubiquitous data. In general, EBD-MLE is a complete mechanism that allows a single-block to be inserted, modified, or deleted securely and efficiently each time under BL-MLE. In this work, we classify users into three categories for access control concerns. We identify that only those users who own files can perform block operations on the file. Meanwhile, we introduce the concept of shadow sets, trivial tag sets, and metadata completion to solve the above three issues. While security proof validates our proposal, the experimental evidence suggests that EBD-MLE is sufficient for a computation-restrained device
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- 2017
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15. Statistical modeling and signal reconstruction processing method of EMF for slurry flow measurement
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Ran Zhang, Zhen Zhang, Shuang-Long Yang, Ke-Jun Xu, Li-Ping Liang, and Xiao-Fen Wang
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Engineering ,Digital signal processor ,Accuracy and precision ,Signal reconstruction ,business.industry ,Water flow ,Applied Mathematics ,Acoustics ,Response time ,Condensed Matter Physics ,Slurry ,Electronic engineering ,Electrical and Electronic Engineering ,business ,Instrumentation ,Digital signal processing ,Voltage - Abstract
According to the experimental data, an amplitude probability density function (PDF) model of the slurry flow signal is built up for electromagnetic flowmeter (EMF) by the method combining statistical analysis with numerical fitting, in order to reveal the effect of slurry noise on the flow signal and describe the features of slurry flow signal. Based on this model, a signal reconstruction processing algorithm is proposed to deal with the output signal of EMF sensor for realizing the slurry flow measurement. At the same time, the high-low voltage switching mode based square-wave excitation method is presented for EMF so as to reduce the slurry noise interferences. A slurry-type EMF transmitter is developed with a DSP chip – TMS320F28335, to implement the signal processing algorithm and control function. Finally water flow calibrations and slurry flow experiments are conducted to verify the reliability and stability of the method and system. Experimental results show that its measurement accuracy of water flow is better than 0.5%, and its steady-state volatility of paper slurry is less than 3%, and its dynamic response time is less than 4 s.
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- 2014
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16. Image Retrieval of Self-Adapt Distance Measure Based on SLLE
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Xiao Fen Wang, Jiang Ping Song, Xiu Rong Qiu, Ke Xin Zhang, and Hai Na Zhang
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business.industry ,General Engineering ,Nonlinear dimensionality reduction ,Pattern recognition ,Interval (mathematics) ,Measure (mathematics) ,Discriminative model ,Dimension (vector space) ,Content (measure theory) ,Computer vision ,Artificial intelligence ,business ,Image retrieval ,Distance transform ,Mathematics - Abstract
Self-adapt distance measure supervised locally linear embedding solves the problem that Euclidean distance measure can not apart from samples in content-based image retrieval. This method uses discriminative distance measure to construct k-NN and effectively keeps its topological structure in high dimension space, meanwhile it broadens interval of samples and strengthens the ability of classifying. Experiment results show the ADM-SLLE date-reducing-dimension method speeds up the image retrieval and acquires high accurate rate in retrieval.
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- 2014
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17. Design and Development of Virtual Interactive System for Paper-Cut Producing Process
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Yan Zhen Wang and Xiao Fen Wang
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Multimedia ,Process (engineering) ,Computer science ,Paper cut ,General Medicine ,medicine.disease ,computer.software_genre ,Visual arts education ,Product (business) ,Inheritance (object-oriented programming) ,Development (topology) ,Order (business) ,medicine ,computer - Abstract
In order to satisfy the strong demands of learning paper-cut from the public and paper-cut lovers and the needs of art education and training to practical ability for children and teenagers.Taking full use of the advantages and features of 2D interactive animation, we designed and implemented a virtual interactive system based on the classification of paper-cutting technique. Learners without paper-cutting experience can master the basic techniques of paper-cutting, and appreciate the integrity of the production process of paper-cutting through this system, which will promote the inheritance and development of folk paper-cut product techniques.
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- 2014
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18. Cerebral ischemia-reperfusion-induced autophagy protects against neuronal injury by mitochondrial clearance
- Author
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Zhong Chen, Yun Cheng, Haijing Yan, Xiao-fen Wang, Xiangnan Zhang, Jieqiong Gao, Guanghui Wang, Weiwei Hu, Zhe Shen, Yang Yuan, Yao Shen, and Rong-rong Wang
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Male ,Programmed cell death ,Ubiquitin-Protein Ligases ,ATG5 ,Ischemia ,Apoptosis ,Biology ,Mitochondrion ,Autophagy-Related Protein 7 ,Neuroprotection ,Autophagy-Related Protein 5 ,Brain Ischemia ,Mice ,Mitophagy ,Autophagy ,medicine ,Animals ,Hypoxia ,Molecular Biology ,Quinazolinones ,Neurons ,Adenine ,Cytochromes c ,Correction ,Cell Biology ,Anatomy ,medicine.disease ,Mitochondria ,Rats ,Cell biology ,Mice, Inbred C57BL ,Glucose ,Cytoprotection ,Reperfusion Injury ,Microtubule-Associated Proteins - Abstract
Cerebral ischemia-reperfusion (I-R) is a complex pathological process. Although autophagy can be evoked by ischemia, its involvement in the reperfusion phase after ischemia and its contribution to the fate of neurons remains largely unknown. In the present investigation, we found that autophagy was activated in the reperfusion phase, as revealed in both mice with middle cerebral artery occlusion and oxygen-glucose deprived cortical neurons in culture. Interestingly, in contrast to that in permanent ischemia, inhibition of autophagy (by 3-methyladenine, bafilomycin A 1, Atg7 knockdown or in atg5(-/-) MEF cells) in the reperfusion phase reinforced, rather than reduced, the brain and cell injury induced by I-R. Inhibition of autophagy either with 3-methyladenine or Atg7 knockdown enhanced the I-R-induced release of cytochrome c and the downstream activation of apoptosis. Moreover, MitoTracker Red-labeled neuronal mitochondria increasingly overlapped with GFP-LC3-labeled autophagosomes during reperfusion, suggesting the presence of mitophagy. The mitochondrial clearance in I-R was reversed by 3-methyladenine and Atg7 silencing, further suggesting that mitophagy underlies the neuroprotection by autophagy. In support, administration of the mitophagy inhibitor mdivi-1 in the reperfusion phase aggravated the ischemia-induced neuronal injury both in vivo and in vitro. PARK2 translocated to mitochondria during reperfusion and Park2 knockdown aggravated ischemia-induced neuronal cell death. In conclusion, the results indicated that autophagy plays different roles in cerebral ischemia and subsequent reperfusion. The protective role of autophagy during reperfusion may be attributable to mitophagy-related mitochondrial clearance and inhibition of downstream apoptosis. PARK2 may be involved in the mitophagy process.
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- 2013
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19. Transient Lack of Glucose but not O2is Involved in Ischemic Postconditioning-Induced Neuroprotection
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Zhong Chen, Zhe Shen, Xiao-fen Wang, Xiangnan Zhang, Weiwei Hu, Ping He, Yanying Fan, and Yao Shen
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Brain Infarction ,Male ,Time Factors ,Ischemia ,Glutamic Acid ,Infarction ,Endogeny ,In Vitro Techniques ,Pharmacology ,Neuroprotection ,Mice ,Glutamate-Ammonia Ligase ,Physiology (medical) ,Occlusion ,medicine ,Animals ,Pharmacology (medical) ,Hypoxia ,Chromatography, High Pressure Liquid ,gamma-Aminobutyric Acid ,business.industry ,Glutamate receptor ,Infarction, Middle Cerebral Artery ,Original Articles ,Hypoxia (medical) ,medicine.disease ,Mice, Inbred C57BL ,carbohydrates (lipids) ,Disease Models, Animal ,Psychiatry and Mental health ,Glucose ,nervous system ,Anesthesia ,Reperfusion ,medicine.symptom ,business ,Reperfusion injury - Abstract
Summary Aim Cerebral ischemic postconditioning has emerged recently as a kind of endogenous strategy for neuroprotection. We set out to test whether hypoxia or glucose deprivation (GD) would substitute for ischemia in postconditioning. Methods Adult male C57BL/6J mice were treated with postconditioning evoked by ischemia (bilateral common carotid arteries occlusion) or hypoxia (8% O2) after 45-min middle cerebral arterial occlusion. Corticostriatal slices from mice were subjected to 1-min oxygen-glucose deprivation (OGD), GD, or oxygen deprivation (OD) postconditioning at 5 min after 15-min OGD. Results Hypoxic postconditioning did not decrease infarct volume or improve neurologic function at 24 h after reperfusion, while ischemic postconditioning did. Similarly, OGD and GD but not OD postconditioning attenuated the OGD/reperfusion-induced injury in corticostriatal slices. The effective duration of low-glucose (1 mmol/L) postconditioning was longer than that of OGD postconditioning. Moreover, OGD and GD but not OD postconditioning reversed the changes of glutamate, GABA, glutamate transporter-1 protein expression, and glutamine synthetase activity induced by OGD/reperfusion. Conclusions These results suggest that the transient lack of glucose but not oxygen plays a key role in ischemic postconditioning-induced neuroprotection, at least partly by regulating glutamate metabolism. Low-glucose postconditioning might be a clinically safe and feasible therapeutic approach against cerebral ischemia/reperfusion injury.
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- 2012
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20. Acidic preconditioning protects against ischemia-induced brain injury
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Xiao-fen Wang, Xiao-hui Song, Chen-hui Zhang, Xiangnan Zhang, Zhong Chen, Jing-ying Zhang, Jia-yan Xiong, Ying-Ying Tang, Qing Li, Zhe Shen, Jieqiong Gao, Yao Shen, and Yanying Fan
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Male ,Cell ,Ischemia ,Hippocampal formation ,Pharmacology ,Brain Ischemia ,Mice ,chemistry.chemical_compound ,Animals ,Medicine ,Ischemic Preconditioning ,Acidosis ,Brain Chemistry ,Membrane potential ,business.industry ,General Neuroscience ,MPTP ,Carbon Dioxide ,Hydrogen-Ion Concentration ,medicine.disease ,Mice, Inbred C57BL ,Treatment Outcome ,medicine.anatomical_structure ,chemistry ,Apoptosis ,Brain Injuries ,Anesthesia ,Ischemic preconditioning ,medicine.symptom ,business - Abstract
Ischemic preconditioning protects against cerebral ischemia. Recent investigations indicated that acidic preconditioning (APC) protects against ischemia-induced cardiomyocytes injury. However, it is not clear whether APC can protect against cerebral ischemia. To address this issue, C57BL/6 mice were exposed 3 times at 10-min intervals to a normoxic atmosphere containing 20% CO(2) for 5 min before being further subjected to bilateral common carotid artery occlusion. APC reversed the ischemia-induced brain injury as revealed by improved performance in passive avoidance experiments and decreased neuron loss in the hippocampal CA1 region. Consistently, both APC-treated brain slices and primary cultured neurons were more resistant to oxygen-glucose-deprivation (OGD)-induced injury, in a pH- and time-dependent manner, as revealed by reversed cell/tissue viability. In addition, the APC treatment prevented OGD-induced mitochondrial transmembrane potential loss and apoptosis, which was inhibited by the mitochondrial permeability transport pore opener atractyloside. Taken together, these findings indicated that APC protects against ischemia-induced neuronal injury. The beneficial effects may be attributed, at least in part, to decreased mitochondria-dependent neuronal apoptosis.
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- 2012
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21. Survival and Performance of Two Cellulose-Degrading Microbial Systems Inoculated into Wheat Straw-Amended Soil
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Xiao juan Wang, Dong Dong Zhang, Pei Pei Li, Xiao Fen Wang, and Zongjun Cui
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DNA, Bacterial ,Cellulase ,Biology ,DNA, Ribosomal ,complex mixtures ,Applied Microbiology and Biotechnology ,Incubation period ,Soil ,RNA, Ribosomal, 16S ,Organic Chemicals ,Cellulose ,DNA, Fungal ,Microbial inoculant ,Incubation ,Soil Microbiology ,Triticum ,Microbial Viability ,Plant Stems ,Denaturing Gradient Gel Electrophoresis ,Soil organic matter ,food and beverages ,Sequence Analysis, DNA ,General Medicine ,Mineralization (soil science) ,Straw ,Biota ,DNA Fingerprinting ,Horticulture ,Agronomy ,RNA, Ribosomal ,biology.protein ,Temperature gradient gel electrophoresis ,Biotechnology - Abstract
A cellulose-degrading composite microbial system containing a mixture of microbes was previously shown to demonstrate a high straw-degrading capacity. To estimate its potential utilization as an inoculant to accelerate straw biodegradation after returning straw to the field, two cellulose-degrading composite microbial systems named ADS3 and WSD5 were inoculated into wheat straw-amended soil in the laboratory. The microbial survival of the inoculant was confirmed by a denaturing gradient gel electrophoresis (DGGE) analysis, whereas the enhancement of straw degradation in soil was assessed by measuring the mineralization of the soil organic matter and the soil cellulase activity. The results indicated that most of the DGGE bands from ADS3 were detected after inoculation into straw-amended autoclaved soil, yet only certain bands from ADS3 and WSD5 were detected after inoculation into straw-amended non-autoclaved soil during five weeks of incubation; some bands were detected during the first two weeks after inoculation, and then disappeared in later stages. Organic matter mineralization was significantly higher in the soil inoculants ADS3 and WSD5 than in the uninoculated controls during the first week, yet the enhanced degradation did not persist during the subsequent incubation. Similar to the increase in soil organic matter, the cellulase activity also increased during the first week in the ADS3 and WSD5 treatments, yet decreased during the remainder of the incubation period. Thus, it was concluded that, although the survival and performance of the two inoculants did not persist in the soil, a significant enhancement of degradation was present during the early stage of incubation.
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- 2012
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22. Research on modelling digital paper-cut preservation
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Ying-Rui Liu, Xiao-Fen Wang, and Wen-Sheng Zhang
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Multimedia ,Intangible cultural heritage ,Computer science ,business.industry ,Applied Mathematics ,computer.software_genre ,Information science ,Computer Science Applications ,Cultural heritage ,Control and Systems Engineering ,Digital preservation ,Modeling and Simulation ,Icon ,Artificial intelligence ,business ,computer ,Digitization ,Folk culture ,Digital paper ,computer.programming_language - Abstract
This paper studies the model of the digital preservation of paper-cut after analyzing the state-of-the-art of the preservation of intangible cultural heritage at home and abroad, focusing on paper-cutting in Hebei, China in a comprehensive approach of sociology, anthropology, folk art, folklore, communication, computer, and information science. Models, methods, and solutions for the preservation and retention of national and folk cultural heritage are proposed. A virtual multimedia interactive system framework of the digital preservation of national and folk cultural heritage is constructed. The standards of paper-cut digitization are studied. The main content of the paper involves: regulated data collection and recording of the scattered Chinese folk paper-cut works in Hebei; digitization, optimization, compression, classification, icon and pattern extraction, vectorization, and work analysis of the first-hand material. This paper also investigates the demonstration, dissemination, database construction, and retrieval of the classified material, icons, and patterns; the demonstration of the reconstruction and application of icon and pattern database; the design and development of an immersive virtual gaming platform of the multi-media scenes and production process of folk paper-cut.
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- 2009
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23. Identification of sensor block model using Volterra series and frequency response function
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Xiao-Fen Wang and Ke-Jun Xu
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Frequency response ,Nonlinear system identification ,Noise (signal processing) ,Applied Mathematics ,Volterra series ,Condensed Matter Physics ,Nonlinear system ,symbols.namesake ,Gaussian noise ,Control theory ,symbols ,Electrical and Electronic Engineering ,Instrumentation ,Bispectrum ,Mathematics ,Block (data storage) - Abstract
This paper proposes a kind of identification method of block models to describe the nonlinear dynamic characteristics of sensors. The Volterra series are employed to analyze the block models and separate the higher-order Volterra kernels of the block models. The estimation method of frequency response function in the non-parametric form is used to identify the model of linear dynamic subsystem. And then coefficients of the nonlinear static subsystem are determined according to the nonlinear outputs of various orders. The identification method only needs the step or impact signal with different amplitudes as the input. These experimental data can be obtained in the calibration experiments of sensors easily. Considering the random noise or Gaussian noise in calibration experiments, the correlation function and bispectrum are used to reduce the influence of noise and improve the calculation precision. The method is applied to the hot-film mass air flow sensor for building its nonlinear dynamic model.
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- 2008
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24. Fundamental wave extraction and frequency measurement based on IIR wavelet filter banks
- Author
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Ke-Jun Xu, Yong-Shan Li, and Xiao-Fen Wang
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Discrete wavelet transform ,Engineering ,business.industry ,Applied Mathematics ,Second-generation wavelet transform ,Stationary wavelet transform ,Wavelet transform ,Filter (signal processing) ,Condensed Matter Physics ,Wavelet packet decomposition ,Wavelet ,Electronic engineering ,Electrical and Electronic Engineering ,business ,Instrumentation ,Digital signal processing - Abstract
A wavelet function with good frequency response was adopted and the optimal decomposition level of wavelet transform was studied in order to improve the accuracy of fundamental wave extraction and frequency measurement in signal processing. In frequency measurements, an evaluating method was proposed to determine right maximal value points, and the fundamental frequency of signal was estimated by the least squares method, which could reduce the influence of low frequency noises. An interpolation method in parabola form was used to eliminate the error of the non-integral period sampling. A digital signal processing system was developed with a digital signal processor (DSP) to realise the wavelet filter and frequency measurement algorithms in real time. The testing results show that both the methods and system proposed by this paper are effective.
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- 2007
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25. Identification and application of the signal model for the electromagnetic flowmeter under sinusoidal excitation
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Xiao-Fen Wang and Ke-Jun Xu
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Physics ,Applied Mathematics ,Phase (waves) ,law.invention ,Signal transition ,Amplitude ,Analog signal ,law ,Control theory ,Demodulation ,Signal transfer function ,Transformer ,Instrumentation ,Engineering (miscellaneous) ,Group delay and phase delay - Abstract
The sensor output of the electromagnetic flowmeter with sinusoidal excitation is analysed theoretically, and the signal expression is deduced to describe the variations of the amplitude and phase shift with the flow rate and excitation and to reflect the effects of transformer and eddy current. The parameters of the signal model are identified by means of the least-squares fitting according to the experimental data. Compared with the existing signal models, this signal model expresses fully the time delay of the sensor signal and contains completely the actions of both the frequency and amplitude of the exciting current. Furthermore, the phase information provided by the signal model is applied to adjust the phase of the reference signal in demodulation and reduce the zero offset of the sensor output.
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- 2007
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26. Signal modeling of electromagnetic flowmeter under sine wave excitation using two-stage fitting method
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Ke-Jun Xu and Xiao-Fen Wang
- Subjects
Physics ,Acoustics ,Metals and Alloys ,Condensed Matter Physics ,Electromagnetic flowmeter ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Volumetric flow rate ,law.invention ,Amplitude ,Sine wave ,Signal modeling ,law ,Electronic engineering ,Eddy current ,Electrical and Electronic Engineering ,Transformer ,Instrumentation ,Excitation - Abstract
The current signal models of electromagnetic flowmeter under sinusoidal excitation cannot describe quantitatively the relationship among the sensor output, flow rate and exciting signal. A two-stage fitting method is proposed to build up the accurate signal model based on experimental data. The first step of the method is to approximate the relationship between the sensor output and the flow rate, and the second one is to fit the relationship between the model coefficients and the frequency or amplitude of exciting current. This method can determine the terms and coefficients of signal model, and reflect the effects of transformer and eddy current.
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- 2007
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27. Non-linear dynamic modeling of hot-film/wire MAF sensors with two-stage identification based on Hammerstein model
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Hao Ren, Xiao-Fen Wang, Qin Teng, and Ke-Jun Xu
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Automotive engine ,Accuracy and precision ,Measure (data warehouse) ,Engineering ,business.industry ,Mass flow sensor ,Metals and Alloys ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Step response ,Control theory ,Range (statistics) ,Air–fuel ratio ,Electrical and Electronic Engineering ,business ,Instrumentation ,Reliability (statistics) - Abstract
The hot-film/wire MAF sensors are widely used in automotive engines to measure the intake mass air flow for controlling the air fuel ratio due to their quick response, wide range and high reliability. However their non-linear dynamic characteristics influence the measurement accuracy of the hot-film/wire MAF sensors. In order to describe the sensor characteristics, this paper proposes a two-stage identification method based on the Hammerstein model and the experimental data of multi-amplitude step response. The modeling results show that the non-linear dynamic models of hot-film/wire MAF sensors are more accurate than the linear dynamic models, and convenient for sensor non-linear dynamic correction. This modeling method can also be applied to other sensors.
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- 2007
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28. Effects of water-soluble carbohydrate content on silage fermentation of wheat straw
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Zongjun Cui, Jian Bin Liu, Yasuo Igarashi, Hongyan Yang, Masaharu Ishii, Li Juan Gao, and Xiao Fen Wang
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Electrophoresis ,Time Factors ,Silage ,Carbohydrates ,Bioengineering ,Applied Microbiology and Biotechnology ,chemistry.chemical_compound ,Animal science ,Botany ,Dry matter ,Lactic Acid ,Water content ,Phylogeny ,Triticum ,Water ,food and beverages ,Hydrogen-Ion Concentration ,Carbohydrate ,Straw ,Lactic acid ,Glucose ,chemistry ,Fermentation ,Carbohydrate Metabolism ,Temperature gradient gel electrophoresis ,Biotechnology - Abstract
To determine a suitable initial water-soluble carbohydrate (WSC) content to make wheat straw natural fermentation successful and to study fermentation characteristics, glucose was used to adjust the initial WSC content to 1.4%, 4.0%, 5.0%, 6.0%, 7.0%, 8.0%, 9.0%, and 10.0% dry matter (DM) in the wheat straw. At 30 d of fermentation, there were three pHs: when the initial WSC content was 1.4%, the pH was 5.5; when the initial WSC contents were 4.0%, 5.0% and 6.0%, the pHs were near 5.1; and when the initial WSC contents were 7.0%, 8.0%, 9.0% and 10.0%, the pHs were near 4.0. The pattern of changes in WSC content during the fermentation was similar to that in pH. At 30 d of fermentation, there existed a dividing line in WSC remnants between the initial 6.0% WSC treatment and the initial 7.0% WSC treatment. When the initial WSC content was more than 7.0%, the remaining WSC content was more than 23.7 g/kg DM. When the initial WSC content was less than 6.0%, the remaining WSC content was less than 13.6 g/kg DM. Particularly for the 1.4% WSC treatment, the remaining WSC content was 2.1 g/kg DM. The results of the microbiological enumeration showed that with the increase in initial WSC content, the numbers of lactic acid bacteria (LAB) and other bacteria generally decreased. Denaturing gradient gel electrophoresis (DGGE) results showed that when the initial WSC content was beyond 7.0%, the LAB of the fermentation system were detected.
- Published
- 2006
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29. Blocking Platelet Aggregation Inhibits Thromboxane A2 Formation by Low Dose Agonists But Does Not Inhibit Phosphorylation and Activation of Cytosolic Phospholipase A2
- Author
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Roger C. Carroll, Xiao-fen Wang, Beat Steiner, François Lanza, and W. C. Kouns
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Blood Platelets ,Agonist ,Serotonin ,medicine.medical_specialty ,medicine.drug_class ,Platelet Glycoprotein GPIIb-IIIa Complex ,Acetates ,Cytoplasmic Granules ,Serotonin secretion ,Plasma ,Thromboxane A2 ,chemistry.chemical_compound ,Cytosol ,Phospholipase A2 ,Internal medicine ,Lysophosphatidic acid ,Thrombin receptor ,medicine ,Humans ,Vasoconstrictor Agents ,Phosphorylase a ,Platelet ,Phosphorylation ,Dose-Response Relationship, Drug ,biology ,Hematology ,Peptide Fragments ,Adenosine Diphosphate ,Enzyme Activation ,Endocrinology ,chemistry ,15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid ,biology.protein ,Tyrosine ,Platelet aggregation inhibitor ,lipids (amino acids, peptides, and proteins) ,Lysophospholipids ,Platelet Aggregation Inhibitors ,Thrombasthenia ,circulatory and respiratory physiology - Abstract
Inhibition of aggregation by Ro 44-9883, a potent and selective non-peptide GPIIb/IIIa antagonist, resulted in inhibition of serotonin secretion induced by weak agonists such as ADP or low doses of either thrombin receptor agonist peptide (TRAP) or collagen. In contrast, alpha granule secretion was inhibited to different extents dependent on donor, averaging 60% inhibition. Inhibition of serotonin secretion correlated with an inhibition of thromboxane A2 (TxA2) formation, both of which were overcome by higher doses of TRAP or collagen. Ro 44-9883 had no effect on the already reduced serotonin secretion and TxA2 formation in Glanzmann's thrombasthenic platelets. Restoration of serotonin secretion in the absence of aggregation requires both TxA2 and lysophosphatidic acid. In addition, Ro 44-9883 inhibition of TxA2 formation was not due to a lack of phospholipase A2 (PLA2) phosphorylation and activation as assayed in vitro. These results suggest that aggregation is required for weak or low dose agonist induced in vivo activity of PLA2, possibly by either regulating phospholipid substrate availability or interaction of PLA2 with platelet membranes.
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- 1997
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30. Histamine H3 receptors aggravate cerebral ischaemic injury by histamine-independent mechanisms
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Xiangnan Zhang, Zhong Chen, Weiwei Hu, Hiroshi Ohtsu, Xingzhou Zhang, Haijing Yan, Guanghui Wang, Yao Shen, Jing Ma, Jianxin Lv, Feng Han, Wei-Wei Hou, Xiao-fen Wang, and Jieqiong Gao
- Subjects
Agonist ,Male ,medicine.drug_class ,General Physics and Astronomy ,Pharmacology ,Histidine Decarboxylase ,Neuroprotection ,General Biochemistry, Genetics and Molecular Biology ,Article ,Autophagy-Related Protein 5 ,Brain Ischemia ,Histamine Agonists ,Mitochondrial Proteins ,chemistry.chemical_compound ,Mice ,Chloride Channels ,medicine ,Animals ,Receptors, Histamine H3 ,Receptor ,PI3K/AKT/mTOR pathway ,Mice, Knockout ,Multidisciplinary ,Autophagy ,General Chemistry ,Histidine decarboxylase ,chemistry ,Histamine H3 receptor ,Microtubule-Associated Proteins ,Histamine ,Histamine H3 Antagonists - Abstract
The role of the histamine H3 receptor (H3R) in cerebral ischaemia/reperfusion (I/R) injury remains unknown. Here we show that H3R expression is upregulated after I/R in two mouse models. H3R antagonists and H3R knockout attenuate I/R injury, which is reversed by an H3R-selective agonist. Interestingly, H1R and H2R antagonists, a histidine decarboxylase (HDC) inhibitor and HDC knockout all fail to compromise the protection by H3R blockade. H3R blockade inhibits mTOR phosphorylation and reinforces autophagy. The neuroprotection by H3R antagonism is reversed by 3-methyladenine and siRNA for Atg7, and is diminished in Atg5−/− mouse embryonic fibroblasts. Furthermore, the peptide Tat-H3RCT414-436, which blocks CLIC4 binding with H3Rs, or siRNA for CLIC4, further increases I/R-induced autophagy and protects against I/R injury. Therefore, H3R promotes I/R injury while its antagonism protects against ischaemic injury via histamine-independent mechanisms that involve suppressing H3R/CLIC4 binding-activated autophagy, suggesting that H3R inhibition is a therapeutic target for cerebral ischaemia., Histamine H3 receptor dysregulation is a hallmark of pathological conditions in the central nervous system, and H3 receptor antagonism is neuroprotective. Here Chen et al. show that histamine-independent H3 receptor activation can enhance neuronal cell death during cerebral ischaemia by suppressing autophagy.
- Published
- 2013
31. Characteristics and community diversity of a wheat straw-colonizing microbial community
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Xu feng Yuan, Xiao juan Wang, Xiao Fen Wang, Zongjun Cui, Jiajia Li, and Hui Wang
- Subjects
food and beverages ,Cellulase ,Biology ,Straw ,Applied Microbiology and Biotechnology ,Enzyme assay ,chemistry.chemical_compound ,chemistry ,Microbial population biology ,Botany ,Genetics ,Xylanase ,biology.protein ,Lignin ,Microbial community, lignocellulose degradation, filter paper activity, CMCase, avicelase, β- glucosidase, xylanase ,Hemicellulose ,Food science ,Cellulose ,Agronomy and Crop Science ,Molecular Biology ,Biotechnology - Abstract
A microbial community named WSD-5 was successfully selected from plant litter and soil after longterm directed acclimation at normal temperature. After 15 days of cultivation at 30°C, the degradation rate of wheat straw by WSD-5 was 75.6%. For cellulose, hemicellulose and lignin, the degradation rates were 94.2, 81.9 and 21.3%, respectively. The optimal pH for filter paper, CMCase, avicelase, β- glucosidase and xylanse activities was 6.24, 6.24, 5.91, 5.91 and 6.24, respectively. The optimal reaction temperature for all enzyme activity was 55°C. Filter paper enzyme, cellulase and xylanase were secreted from the degradation of wheat straw by WSD-5. The highest filter paper, cellulose endonuclease (CMCase), cellulose exonuclease (avicelase), β-glucosidase and xylanase activities were 1.30, 4.35, 0.60, 0.43 and 15.16 U/ml, respectively. A library of bacterial and fungal ribosomal gene sequences obtained from the community showed the presence of Ochrobactrum sp, Coprinus cinereus and Pseudallescheria boydii . To our knowledge, this was the first report of a microbial community which consisted of bacteria and fungi and was selected in the presence of wheat straw to produce extracellular filter paper enzyme, cellulase and xylanase. Key words: Microbial community, lignocellulose degradation, filter paper activity, CMCase, avicelase, β- glucosidase, xylanase.
- Published
- 2013
32. Modulation of astrocytic glutamine synthetase expression and cell viability by histamine in cultured cortical astrocytes exposed to OGD insults
- Author
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Li Tan, Haijing Yan, Zhong Chen, Jieqiong Gao, Weiwei Hu, Juan Li, Wei-Wei Hou, Xiao-fen Wang, Yueyang Tian, Xiaojie Shi, and Yao Shen
- Subjects
medicine.medical_specialty ,Cell Survival ,Histamine H1 receptor ,Biology ,Neuroprotection ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Histamine H2 receptor ,Glutamate-Ammonia Ligase ,Internal medicine ,Glutamine synthetase ,medicine ,Animals ,Cell damage ,Cells, Cultured ,Cerebral Cortex ,Dose-Response Relationship, Drug ,General Neuroscience ,Glutamate receptor ,medicine.disease ,Rats ,Oxygen ,medicine.anatomical_structure ,Endocrinology ,Glucose ,chemistry ,Astrocytes ,Histamine ,Astrocyte - Abstract
Histamine, a neurotransmitter or neuromodulator has been demonstrated to be neuroprotective in cerebral ischemia. However, few reports concern its function on astrocytes during cerebral ischemia. The purpose of this study was to investigate the effects of histamine on astrocytic cell damage and glutamate signaling, especially on glutamine synthetase (GS) expression in primary cultured cortical astrocytes exposed to oxygen-glucose deprivation (OGD) insult. OGD for 6h caused a severe damage of astrocytic mitochondrial function, and decreased GS expression and then increased the extracellular glutamate level. Pretreatment with histamine significantly prevented the cell damage and rescued the expression of GS in a concentration-dependent manner. The protective effect of histamine on astrocytic cell damage could be partly reversed either by H1 receptor antagonist pyrilamine or H2 receptor antagonist cimetidine. However, the regulatory effect of histamine on GS expression was antagonized only by pyrilamine. In addition, bisindolylmaleimide II, a broad-spectrum inhibitor of PKC, reversed the regulatory action of histamine on GS expression. These results indicate that histamine can effectively protect against OGD-induced cell damage in astrocytes through H1 and H2 receptors, and its regulatory effect on astrocytic GS expression may be due to the activation of H1 receptor and PKC pathway. Histamine may be an endogenous protective factor and calls for its further study as a regulator of astrocyte function during ischemic stroke.
- Published
- 2013
33. Histamine up-regulates astrocytic glutamate transporter 1 and protects neurons against ischemic injury
- Author
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Miaomiao Jin, Xiao-fen Wang, Weiwei Hu, Qi Fang, Wei-Zheng Zeng, Tian-Le Xu, Yao Shen, Shi-Hong Zhang, Yang Yang, Zhong Chen, Guo-Dong Lou, and Haijing Yan
- Subjects
Male ,Excitotoxicity ,Histamine H1 receptor ,Pharmacology ,Biology ,medicine.disease_cause ,Neuroprotection ,Hippocampus ,Brain Ischemia ,Rats, Sprague-Dawley ,Cellular and Molecular Neuroscience ,chemistry.chemical_compound ,medicine ,Glutamate aspartate transporter ,Animals ,Neurons ,Histamine trifluoromethyl toluidide ,Cell Death ,Glutamate receptor ,Rats ,Up-Regulation ,Neuroprotective Agents ,chemistry ,Biochemistry ,Excitatory Amino Acid Transporter 2 ,Astrocytes ,biology.protein ,Histamine H3 receptor ,Histamine - Abstract
Astrocytic glutamate transporter 1 (GLT-1) is responsible for the majority of extracellular glutamate clearance and is essential for preventing excitotoxicity in the brain. Up-regulation of GLT-1 shows benefit effect on ischemia-induced neuronal damage. In present study, we examined the effect of histamine, a neurotransmitter or neuromodulator, on GLT-1 expression and function. In acute hippocampal slices, histamine selectively increased GLT-1 expression independent of neuronal activities. Similar up-regulation of GLT-1 was also observed after histamine treatment in pure cultured astrocytes, which was abolished by H1 receptor antagonist or PKC inhibitor. Cell surface biotinylation and whole-cell patch recordings of glutamate transporter current confirmed the up-regulation of functional GLT-1 following histamine exposure. Histamine treatment decreased the extracellular glutamate content and alleviated neuronal cell death induced by exogenous glutamate challenge. Moreover, we found a significant neuroprotective effect of histamine in brain slices after oxygen-glucose deprivation (OGD). In addition, histidine, the precursor of histamine, also showed neuroprotection against ischemic injury, which was accompanied by reversion of declined expression of GLT-1 in adult rats subjected to middle cerebral artery occlusion (MCAO). These neuroprotective effects of histamine/histidine were blocked by GLT-1 specific inhibitor dihydrokainate or H1 receptor antagonist. In summary, our results suggest that histamine up-regulates GLT-1 expression and function via astrocytic H1 receptors, thus resulting in neuroprotection against excitotoxicity and ischemic injury.
- Published
- 2013
34. Enhancing the anaerobic digestion of corn stalks using composite microbial pretreatment
- Author
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Xu feng Yuan, Xiao Fen Wang, Xu Cheng, Hui Wang, Pei Pei Li, and Zongjun Cui
- Subjects
Time Factors ,Applied Microbiology and Biotechnology ,Zea mays ,Hydrolysate ,Butyric acid ,chemistry.chemical_compound ,Biogas ,Bioenergy ,Hemicellulose ,Food science ,Anaerobiosis ,Cellulose ,Volatile Organic Compounds ,Bacteria ,Plant Stems ,Hydrolysis ,General Medicine ,Anaerobic digestion ,Agronomy ,chemistry ,Biofuels ,Fermentation ,Digestion ,Methane ,Biotechnology - Abstract
A composite microbial system (XDC-2) was used to pretreat and hydrolyze corn stalk to enhance anaerobic digestion. The results of pretreatment indicated that sCOD concentrations of hydrolysate were highest (8,233 mg/l) at the fifth day. XDC-2 efficiently degraded the corn stalk by nearly 45%, decreasing the cellulose content by 22.7% and the hemicellulose content by 74.1%. Total levels of volatile products peaked on the fifth day. The six major compounds present were ethanol (0.29 g/l), acetic acid (0.55 g/l), 1,2-ethanediol (0.49 g/l), propionic acid (0.15 g/l), butyric acid (0.22 g/l), and glycerine (2.48 g/l). The results of anaerobic digestion showed that corn stalks treated by XDC-2 produced 68.3% more total biogas and 87.9% more total methane than untreated controls. The technical digestion time for the treated corn stalks was 35.7% shorter than without treatment. The composite microbial system pretreatment could be a cost-effective and environmentally friendly microbial method for efficient biological conversion of corn stalk into bioenergy.
- Published
- 2011
35. Paper Construction of a Digital Artistic System for Paper-Cut
- Author
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Na Chen, Shu-feng Duan, Xiao-Fen Wang, Ying-Rui Liu, and Zheng-Xu Zhao
- Subjects
Engineering ,Multimedia ,Folklore ,business.industry ,Paper cut ,Information and Computer Science ,Virtual reality ,medicine.disease ,computer.software_genre ,medicine ,Database construction ,Image tracing ,Icon ,business ,computer ,Digitization ,computer.programming_language - Abstract
This article studies a paper cutting platform in a comprehensive approach to folk art, folklore, communication, computer and information science focusing on paper-cut in Hebei China. The main content includes:①the data collecting and recording of the scattered Chinese folk paper-cut work in Hebei,②the digitization, optimization, compression, classification, icon and pattern extraction, vectorization and work analysis of the first-hand material, ③the demonstration, dissemination, database construction and retrieval of the classified material, icons and patterns,④ the demonstration of the reconstruction and application of icon and pattern database, and ⑤the design and development of immersive virtual gaming platform of the multi-media scenes and production process of folk paper-cut. In this article, a virtual multi-media system framework of paper cutting is constructed.
- Published
- 2010
- Full Text
- View/download PDF
36. Characteristics of a high efficient complex microbial community for degradation of cellulose and lindane
- Author
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Zong-jun Cui, Jun-Ling Niu, Guo-Xue Li, Xiao-fen Wang, and Chang-Li Liu
- Subjects
chemistry.chemical_compound ,Electrophoresis ,Chromatography ,chemistry ,Microbial population biology ,Filter paper ,Microorganism ,Cellulose ,Absorbent cotton ,Pulp and paper industry ,Lindane ,Temperature gradient gel electrophoresis - Abstract
A microbial community with lignocellulose and lindane degradation ability was constructed and domesticated from overheated composting pile. Denaturing gradient gel electrophoresis (DGGE) showed that the DGGE band patterns of the community were different in different cultivation period. The community could degrade different cellulose materials with high efficiency, especially had high degrading activity for the materials with higher native cellulose such as filter paper and absorbent cotton. The more cellulose was decomposed, the more lindane was degraded. The optimum temperature for the community was in the range of 50 to 60°C. It could keep a high capability for degrading cellulose in a wide range of pH, especially under the condition of neutrality and hemi-alkli. Lindane could be degraded effectively under the condition of pH 7∼9, which also was the optimum condition for cellulose degradation. But under the condition of pH 10, the degradation ratio of lindane was reached to 49.62, whereas cellulose was less degraded.
- Published
- 2010
- Full Text
- View/download PDF
37. [Characteristics and diversity of a microbial community decomposing wheat straw under aerobic conditions]
- Author
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Yu-Ling, Dong, Wan-Bin, Zhu, Peng, Guo, Xiao-Fen, Wang, Li-Li, Zhang, and Zong-Jun, Cui
- Subjects
Bacteria, Aerobic ,Clostridium ,Comamonadaceae ,Biodegradation, Environmental ,Plant Stems ,Pseudomonas ,Bacteroides ,Biodiversity ,Triticum ,Refuse Disposal - Abstract
A microbial community with the stable ability of effectively decomposing wheat stalks was constructed at room temperature under aerobic conditions by the method of restricted cultivation. The degradation ability of the microbial community shows that when performed in 100 mL improved CMC liquid medium, the depth and diamerer of the fluid level were 2 cm and 9 cm, it kept higher degradation efficiency with capability of decomposing straws of 66.1% during the initial six days. By the tenth day of decomposition, the degradation ratio was slowly up to 77.0%. Analysis of the components of wheat stalk (1.86 g) showed that the cellulose lost 0.78 g, hemicellulose lost 0.16 g and lignin lost 0.24 g. The composition diversity of the microbial community shows that 13 genera of microorganisms were identified by the technologies of clone library and isolation of pure strain. The results indicated that the dominate genera were Hydrogenophaga, Pseudomonas, Bacteroides and Clostridium taking up 78% in one hundred of positive clones. Phylogenetic dendrogram indicates that the relations among clones and isolated strains and their closest relatives presented certain distances; both Isolated 7 (FJ439527) and Clone 86 (EU834839) were closely related to Pseudomonas xiamenensis.
- Published
- 2010
38. [Screening and characteristics of normal temperature lignocellulose-degradation microbial community]
- Author
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Chang-li, Liu, Wan-bin, Zhu, Peng, Guo, Xiao-juan, Wang, Xiao-fen, Wang, and Zong-jun, Cui
- Subjects
Clostridium ,Biodegradation, Environmental ,Plant Stems ,Temperature ,Brevibacterium ,Oryza ,Lignin ,Refuse Disposal ,Rhizobium - Abstract
A normal temperature lignocellulose-degrading microflora has been constructed by our laboratory. We researched the degradation activity and compose of the community in 28 degrees C fermentation condition. The results showed that the microbial community could degrade 39.6% of rice stew gross weight within five days.The volatile products were detected using CP-Chirasil-Dex CB capillary column by GC-MS, propionic acid, ethanol, isopropyl alcohol, 4-amino-1-butanol, butanoic acid, diethoxydimethyl-silane, lactic acid, ethanol,2,2'-oxybis-, diethyl phthalate and glycerin,more than 10 kinds of volatile products were detected. The state volatile products of changed largely along with the process of decompose, the productions gradually increase, and the content changes much with the process of decompose. Denaturing gradient gel electrophoresis (DGGE) detected the dynamic change of bacterium compose, the bacterium changes much in different period,the result of Blast from 16S rDNA sequence was found that the closest relative in community belong to Clostridium sp., Brevibacillus sp., Rhizobium sp., Bacterium sp. four genera.
- Published
- 2009
39. [Composition diversity of the multifunctional bacterium community NSC-7]
- Author
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Chang-Li, Liu, Xiao-Fen, Wang, Jun-Ling, Niu, Yu-Cai, Lü, Peng, Guo, Hai-Long, Shen, and Zong-Jun, Cui
- Subjects
Clostridium ,Bacteria, Anaerobic ,Bacteria ,RNA, Ribosomal, 16S ,Fermentation ,Proteobacteria ,Electrophoresis, Polyacrylamide Gel ,Biodiversity ,Cellulose ,Paenibacillus ,Hexachlorocyclohexane - Abstract
The NSC-7 microbial community could decompose cellulose and lindan with high efficiency. In order to determine the bacterial composition of the community, 11 isolate strains were detected by plate isolation, while a community reset by the 11 isolate strains lost the capacity of degrading cellulose. The capacity of degrading of the filter paper in double deck plate and monolayer plate were determined, only the filter paper in double deck plate were degraded, that means the main or key microbe are anaerobic. The denaturing gradient gel electrophoresis (DGGE) and construction of 16S rDNA clone library were used to identify the composition diversity of NSC-7 community. 195 clones and 25 strains were detected in clone library, and about 60% closest relative among them was known the detailed information which were belonged to Clostridium, Petrobacter, Bacteria, Paenibacillus, Proteobacterium. Furthermore, there were 40% closest relative belonged to uncultured bacterium clone.
- Published
- 2009
40. [Carbendazim affects testicular development and spermatogenic function in rats]
- Author
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Gong-chang, Yu, Lin, Xie, Yan-zhong, Liu, and Xiao-fen, Wang
- Subjects
Male ,Testis ,Animals ,Down-Regulation ,Apoptosis ,Benzimidazoles ,Carbamates ,Rats, Wistar ,Spermatogenesis ,Rats ,bcl-2-Associated X Protein - Abstract
To explore the effects of carbendazim on the testicular development and spermatogenic function of male rats and its action mechanism.Forty clean-grade impubic male Wistar rats were equally randomized into a low-dose, a medium-dose, a high-dose and a control group, treated respectively with carbendazim at 20, 100 and 200 mg/kg (bw) and Tween-80 solution, all by oral gavage once a day for 80 days. After treatment, the rats were weighed, their testes and epididymides immediately excised, their morphological changes observed and the weights of the right testis and epididymis obtained. Sperm motility and counts in the left cauda epididymis were determined. Histopathological changes, cell apoptosis and the expression of Bcl-2/Bax in the testis were detected by HE staining, TUNEL and immunohistochemical SABC method.The medium- and high-dose groups showed obviously atrophic testes and epididymides, marked histopathological abnormality of the testis, reduced weight of the right testis and epididymis, and decreased sperm motility and counts in the left cauda epididymis (P0.01). With the increasing dose of carbendazim, the apoptosis rate and Bax expression were significantly raised, while the expression of Bcl-2 significantly decreased (P0.05, P0.01).Carbendazim affects the testicular development and spermatogenic function of male rats, and the mechanism may involve cell apoptosis induced by down-regulation of Bcl-2 and up-regulation of Bax.
- Published
- 2009
41. [Degradation of cyanide and maturity in cassava processing wastes composting]
- Author
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Yu-Cai, Lü, Xiao-Fen, Wang, Wan-Bin, Zhu, Xu, Cheng, and Zong-Jun, Cui
- Subjects
Biodegradation, Environmental ,Cyanides ,Manihot ,Fermentation ,Refuse Disposal - Abstract
An investigation was carried out to approach the degradation of cyanide and maturity during the cassava processing wastes composting process. Mixtures of cassava hull, cassava residues and pig manure were used in the experiment. Parameters like temperature, pH, cyanide, cellulose, hemicellulose, lignin and C/N ratio were assessed during the composting process, the effect of composting process on the degradation of cyanide and maturity were evaluated. The results reveal that the content of cyanide decreases sharply and declines to 2.08 mg/kg (30 days of composting), the degradation rate of cyanide is 94.16% and is in accord with food safety standard. After 15 days of the composting process, degradation of composting materials containing carbon (starch, cellulose, hemicellulose) and cyanide are quick and the degradation rates of them are more than 80%, properties tend towards stability basically. During 30 days of the composting process, the composting temperature drops to normal temperature and tends to stability, pH remains stable at 7.2. Parameters like C/N ratio, nitrate-nitrogen (NO3(-)-N) and ammonia nitrogen (NH4(+)-N) as maturity evaluation index were measured, and the results indicate that physical and chemical properties keep stability after 15 days of cassava processing wastes composting process. At the end of fermentation, C/N ratio is 17.55, the content of nitrate-nitrogen and ammonia nitrogen reach 2.5g/kg and 10 mg/kg respectively, NO3(-)-N/NH4(+)-N ratio is 250. The changes of these above mentioned parameters meet with maturity evaluation standard. Proving that cassava processing wastes during 30 days of composting treatment can achieve stability and security state.
- Published
- 2009
42. Applied digital signal processing systems for vortex flowmeter with digital signal processing
- Author
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Sanshan Liu, Zhihai Zhu, Yunzhi Huang, Xiao-Fen Wang, Ke-Jun Xu, Yang Zhou, and Zhi-Yuan Chen
- Subjects
Digital down converter ,Analog transmission ,Computer science ,business.industry ,computer.software_genre ,Digital delay line ,Multidimensional signal processing ,Analog signal ,Electronic engineering ,Signal transfer function ,business ,Audio signal processing ,Instrumentation ,computer ,Digital signal processing - Abstract
The spectral analysis is combined with digital filter to process the vortex sensor signal for reducing the effect of disturbance at low frequency from pipe vibrations and increasing the turndown ratio. Using digital signal processing chip, two kinds of digital signal processing systems are developed to implement these algorithms. One is an integrative system, and the other is a separated system. A limiting amplifier is designed in the input analog condition circuit to adapt large amplitude variation of sensor signal. Some technique measures are taken to improve the accuracy of the output pulse, speed up the response time of the meter, and reduce the fluctuation of the output signal. The experimental results demonstrate the validity of the digital signal processing systems.
- Published
- 2009
43. Involvement of Sertoli cells in spermatogenic failure induced by carbendazim
- Author
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Yanzhong Liu, Lin Xie, Gongchang Yu, and Xiao-fen Wang
- Subjects
Pharmacology ,endocrine system ,medicine.medical_specialty ,biology ,urogenital system ,Carbendazim ,Health, Toxicology and Mutagenesis ,Benzimidazole fungicide ,Motility ,Vimentin ,General Medicine ,Toxicology ,Sertoli cell ,chemistry.chemical_compound ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Internal medicine ,medicine ,biology.protein ,Spermatogenesis ,Spermatogenic failure ,Sperm motility ,medicine.drug - Abstract
The aim of this study is to determine whether Sertoli cells are involved in spermatogenic failure induced by carbendazim, a benzimidazole fungicide that is widely used in agriculture. Total 40 rats were treated with carbendazim by oral gavage at dosages of 0, 20, 100 and 200mg/kg for 60 days. The testis weight, sperm counts, sperm motility and Sertoli cell morphology and secretions including vimentin, ABP, inhibin B, SCFs and SCFm in testis were examined. In 100 and 200mg/kg groups, the testis weight, the sperm counts and motility and SCFm levels were significantly decreased, the sloughing of germ cells and ABP levels were increased, and the vimentin filaments and Sertoli cell morphology were altered. Inhibin B and SCFs levels were unchanged. The results suggested that alterations of Sertoli cell morphology and function were involved in spermatogenic failure induced by carbendazim.
- Published
- 2008
44. [Degradation of cassava residue by the cellulose degradation composite microbial system MC1]
- Author
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Peng, Guo, Xiao-Fen, Wang, Wan-Bin, Zhu, Xu, Cheng, and Zong-Jun, Cui
- Subjects
Biodegradation, Environmental ,Manihot ,Bacteria ,Fermentation ,Cellulose ,Methane - Abstract
The lignocelluloses of cassava residue are good biomass resources. They are mainly used to produce feeds and alcohol. It is a promising approach to utilize them to produce methane. But it is difficult to use cassava residue for producing methane because of its dispersive solid matter and much water. A cellulose degradation composite microbial system MC1 was applied to degrade cassava residue discarded from cassava starch manufactory, and the composition of the lignocelluloses and the soluble ingredients of cassava residue were analyzed. After 18 days' cultivation, the total weight of the cassava residue was reduced by 47.3%, the cellulose, hemi-cellulose and lignin of the cassava residue were reduced by 22.7%, 90.4% and 11.3%, respectively, and 85% of the whole weight relief was made by MC1 within 6 days. The soluble ingredients of the cassava residue were increased from the incipient 18% to 33% in the third day which was the peak value in the process. The total amount of the volatile products, analyzed by GC-MS, came to a maximum in the sixth day. Twelve kinds of volatile products in the fermentation broth were determined, in which ethanol, acetic acid, 1, 2-ethanediol, butanoic acid and glycerine were the major compounds, and they can be utilized by methanogenic organism directly or be changed into compounds that can be utilized by methanogens organism directly. Accordingly, it is very hopeful to use MC1 to degrade cassava residue as a method of prefermentation in methane fermentation.
- Published
- 2008
45. Development of an enrichment culture growing at low temperature used for ensiling rice straw
- Author
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Hong Yan, Yang, Xiao Fen, Wang, Li Juan, Gao, Shin, Haruta, Masaharu, Ishii, Yasuo, Igarashi, and Zong Jun, Cui
- Subjects
DNA, Bacterial ,China ,Plant Stems ,Molecular Sequence Data ,Oryza ,Hydrogen-Ion Concentration ,DNA, Ribosomal ,Cold Temperature ,Lactobacillus ,RNA, Ribosomal, 16S ,Fermentation ,Leuconostoc ,Phylogeny ,Soil Microbiology - Abstract
To speed up the conversion of rice straw into feeds in a low-temperature region, a start culture used for ensiling rice straw at low temperature was selected by continuous enrichment cultivation. During the selection, the microbial source for enrichment was rice straw and soil from two places in Northeast China. Lab-scale rice straw fermentation at 10 degrees C verified, compared with the commercial inocculant, that the selected start culture lowered the pH of the fermented rice straw more rapidly and produced more lactic acid. The results from denatured gradient gel eletrophoresis showed that the selected start culture could colonize into the rice straw fermentation system. To analyze the composition of the culture, a 16S clone library was constructed. Sequencing results showed that the culture mainly consisted of two bacterial species. One (A) belonged to Lactobacillus and another (B) belonged to Leuconostoc. To make clear the roles of composition microbes in the fermented system, quantitative PCR was used. For species A, the DNA mass increased continuously until sixteen days of the fermentation, which occupied 65%. For species B, the DNA mass amounted to 5.5% at six days of the fermentation, which was the maximum relative value during the fermentation. To the authors' best knowledge, this is the first report on ensiling rice straw with a selected starter at low temperature and investigation of the fermented characteristics.
- Published
- 2008
46. [Productions analyses and pH dynamics during rice straw degradation by the lignocellulose degradation bacteria system WSC-6]
- Author
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Wei-Dong, Wang, Xiao-Fen, Wang, Chang-Li, Liu, Yu-Hua, Li, Yu-Cai, Lü, and Zong-Jun, Cui
- Subjects
Glycerol ,Biodegradation, Environmental ,Bacteria ,Plant Stems ,Fermentation ,Oryza ,Lactic Acid ,Hydrogen-Ion Concentration ,Lignin ,Gas Chromatography-Mass Spectrometry ,Acetic Acid ,Culture Media - Abstract
To detect the metabolic characteristic of rice straw degradation by composite microbial system WSC-6, we cultured WSC-6 in the media used rice straw as the limiting carbon source. The rice straw was added in the style of different quantity once or the same quantity at the different time intervals during 90 days culture. The systems were cultivated under static condition at 50 degrees C. The degradation ratio, absolute degradation quantity,products from degradation and dynamics of pH value of fermentation system were all investigated. The results showed: when 1% rice straw was added once, the pH of fermentation system decreased from initial 7.8 to 6.0 within the first three days inoculation, and after six-day cultivation, it increased to 8.0 and was stable. For dissolved oxygen concentration (DO), the value was maintained at range of 0.01 to 0.12 mg x L(-1) of microaerobic condition. During the rice straw degradation, more than ten kinds of products including ethanol, acetic acid, lactic acid and glycerol and so on were detected using GC-MS. Especially, the highest concentration of lactic acid among all products was 7.381 g x L(-1) at 24 h after inoculation. During 90-day cultivation, for the addition treatments of the different quantity once, the more rice straw added, the quicker and lower the pH decreased, and the longer time intervals returned the pHs were. Especially for 5.0% addition, when 5.0% of rice straw was added once, pH did not increase again after it decreased. Among the addition of the same quantity at the different time intervals, the trend of decrease-increase in pH at 12-day and 15-day intervals could be repeated and high degradation activity well maintained. After 90-day of inoculation, the highest degradation ratio occurred in the treatment at 15-day interval, which was 86.7%. The highest absolute quantity occurred in the treatment at 6-day interval, which was 32.4 g. The trend of pH changes can indicate the activity of lignocellulose degradation and degradation process of the WSC-6.
- Published
- 2008
47. [Microbial dynamics during the composting process]
- Author
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Wei-Dong, Wang, Xiao-Fen, Wang, Zhe, Piao, Chang-Li, Liu, Xiu-Zhi, Gao, and Zong-Jun, Cui
- Subjects
Actinobacteria ,Clostridium ,DNA, Bacterial ,Bacteria ,RNA, Ribosomal, 16S ,Population Dynamics ,Fungi ,Electrophoresis, Polyacrylamide Gel ,Fertilizers ,Refuse Disposal - Abstract
Microbial dynamics of microbial community during the composting process was investigated with the methods of denaturing gradient gel electrophoresis (DGGE) and plating. The results showed that the most of microorganism count was bacterium, the second was actinomycete and the least was fungi. At the same time, the count of the thermophilic microorganism was always less than that of the mesophilic during the composting process. The count of mesophilic microorganism at later stage was less than that at the initial stage. However, the count of thermophilic antinomycete and fungi at later stage were more than that at initial stage, and the count of thermophilic bacterium was stable throughout the composting process. The bands pattern of DGGE and 16S rDNA analyses indicated that bacterial succession was presented during the composting process. The genera of Bdellovibrio, Clostridia bacterium and Bacillus were dominant species at initial stage (before the first 15 days), and Beta proteobacterium, Petrobacter succinimandens, Nitrospirae bacterium and Paenibacillus were dominant species at middle and later stage. Moreover, Clostridium was found throughout the process.
- Published
- 2008
48. [Effects of a lactic acid bacteria community SFC-2 treated on rice straw]
- Author
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Li-Juan, Gao, Xiao-Fen, Wang, Hong-Yan, Yang, Xiu-Zhi, Gao, Yu-Cai, Lü, and Zong-Jun, Cui
- Subjects
Lactobacillus ,Plant Stems ,Fermentation ,Electrophoresis, Polyacrylamide Gel ,Oryza ,Lactic Acid ,Refuse Disposal - Abstract
Aimed to utilize rice straw and lessen the pressure of environment, the rice straw was used as the fermentation material, and a lactic acid bacteria community SFC-2 from my laboratory was inoculated into the rice straw to investigate the inoculation effects. After 30 days fermentation, the inoculated fermented straw smelt acid-fragrant, and the pH value was 3.8, which was lower than the control of 4.1. Furthermore, lactic acid concentration was more than that in the control. Especially L-lactic acid concentration was two times more than in the control, and the crude protein content was 10.16% higher than that in the control, and the crude fiber content was 3.2% lower than that in the control. From the patterns of denaturing gradient gel electrophoresis (DGGE), Lactobacillus plantarum, Lactobacillus fermentum and Lactobacillus paracasei rapidly became the advantageous species in the inoculated straws. However, Enterobacter sakazakii, Pantoea agglomerans, Enterobacter endosymbiont, Pantoea ananatis, whichwere predominate in the controls, were not detected in the inoculated straws, and the fermented quality was improved significantly.
- Published
- 2007
49. [Construction and composition diversity of a lactic acid bacterial community SFC-2]
- Author
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Li-juan, Gao, Xiao-fen, Wang, Hong-yan, Yang, Xian-mei, Li, and Zong-jun, Cui
- Subjects
Lactobacillus ,Plant Stems ,RNA, Ribosomal, 16S ,Fermentation ,Oryza ,Biodiversity ,Lactic Acid ,Zea mays - Abstract
To obtain the community that could accelerate the fermentation of the air-dried crop straws, a lactic acid bacteria community SFC-2 was constructed from the natural fermented products of the corn straw and rice straw by continuous restricted subcultivation in the MRS-S broth. The SFC-2 could lower the pH of the broth quickly, and produce high amount of lactic acid. The microbial composition of the SFC-2 became stable from the 25th generation according to the results of denaturing gradient gel electrophoresis (DGGE). The pH value of the SFC-2 dropped to 3.8 and the amount of lactic acid reached 10.64 mg x mL(-1) after 12 h cultivation in the broth, which contained 64% L-(+) lactic acid. Using morphological methods, four strains were isolated from the SFC-2 and they all belonged to Lactobacillus. The closest species were L. fermentum, L. plantarum, L. paracasei and L. paracasei sub sp., respectively. At the same time, the composition of the SFC-2 was also analyzed by constructing 16S rDNA clone library. The results of 16S rDNA sequencing showed that the closest species of seven clones were mainly L. fermentum, L. plantarum and L. paracasei. In clone libraries, 76.3% belonged to L. fermentum, 20.3% belonged to L. plantarum and 3.4% belonged to L. paracasei.
- Published
- 2007
50. [Composition diversity of lactic acid bacteria (LAB) community Al2 used for alfalfa silage]
- Author
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Xiao-Fen, Wang, Li-Juan, Gao, Hong-Yan, Yang, Wei-Dong, Wang, and Zong-Jun, Cui
- Subjects
Lactobacillus ,Silage ,RNA, Ribosomal, 16S ,Fermentation ,Electrophoresis, Polyacrylamide Gel ,Medicago sativa - Abstract
Alfalfa is the most important forage grass that is difficult to ensile for good quality. Using silage inoculants are the important way for preservation of alfalfa silage. Through continuous restricted subcultivation, a lactic acid bacteria (LAB) community Al2 was selected from well-fermented alfalfa silage. Plate isolation and Denaturing Gradient Gel Electrophoresis (DGGE), construction of 16S rDNA clone library were used to identify the composition diversity of Al2 community, with 7 strains detected, and they were all belonged to Lactobacillus. The composition ratios of the 7 strains were 55.21%, 19.79%, 14.58%, 3.13%, 3.13%, 3.13%, 1.03% according to 16S rDNA clone library. Al2-1i, Al2-2i, Al2-3i, corresponding to L. plantarum (99.9%), L. kimchii (99.4%), L. farciminis (100%) were detected by plate isolation. Among 3 isolates, Al2-1i had the highest ability of dropping pH and producing lactic acid, and the amount of lactic acid was reach to 18g/L at 24h cultivated in MRS media. The ability of dropping pH and producing lactic acid of Al2-3i was the lowest. From DGGE profiles, the dominant strains in Al2 community were L. plantarum and L. kimchii. L. plantarum was detected during the whole process, and L. kimchii was detected in the later phase.
- Published
- 2006
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