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Ti R.,Nanjing University | Huang F.,Nanjing University | Zhu W.,Nanjing University | He J.,Nanjing University | And 5 more authors.
Ceramics International | Year: 2015

Single phase Bi4LaTi3FeO15 ceramics with a four-layered Aurivillius structure were synthesized by successfully inserting LaFeO3 into Bi4Ti3O12 matrix, and their structural, multiferroic and dielectric properties were investigated. Typical ferroelectric behavior with remnant polarization (2Pr) of about 12 μC/cm2, large dielectric constant, small dielectric loss and a weak ferromagnetic behavior are obtained simultaneously at room temperature. As a result, possible magnetoelectric coupling effect is obtained near the ferromagnetic Curie temperature. Meanwhile, the weak ferromagnetism can be enhanced at lower temperature, and thus a larger saturation magnetization of about 1.2 emu/g is obtained at 5 K. In addition, two sets of dielectric relaxation are observed and discussed based on defect relaxation theory. © 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Liu F.,Tsinghua University | Cao X.,Tsinghua University | He W.,Tsinghua University | Song J.,Astronaut Research and Training Center | And 6 more authors.
Journal of Biomedical Optics | Year: 2012

Subsurface fluorescence molecular tomography (FMT) has promising potential for noninvasive characterization of molecular and cellular activities in small animals by tomographic means in reflectance geometry. In this work, subsurface FMT is employed to monitor the therapeutic response of cisplatin in tumor-bearing mice in vivo. The localization and quantification accuracy of subsurface FMT are demonstrated in phantom. In the in vivo study, the red fluorescent protein activities not only on the surface but in the interior tumor are tracked three-dimensionally during the antitumor treatment. © 2012 Society of Photo-Optical Instrumentation Engineers (SPIE).

Song J.,State Key Laboratory of Space Medicine Fundamentals and Application | Song J.,Astronaut Research and Training Center | Yan H.,State Key Laboratory of Space Medicine Fundamentals and Application | Yan H.,Astronaut Research and Training Center | And 6 more authors.
Journal of Mechanics in Medicine and Biology | Year: 2011

Changes of STT complex are the main indicators in myocardial ischemia detection based on electrocardiogram (ECG) signals. However, STT complex is highly sensitive to interferences (baseline wandering, postural changes, electrode interference, etc.), especially T-wave has a large morphological variability. Therefore, the feature points of ECG STT complex are very difficult to detect accurately. Currently, the commonly used detection methods for ST-segment include R + x and J + x, but they often misjudges the T-wave rising limb as ST-segment. Therefore, a new accurate hybrid approach for STT detection was proposed in this paper. First, T-wave onsets and offsets were detected using regional method and T-wave peaks were located using function comparing method. Then, a squeeze approach for ST-segment detection was proposed based on R-wave peak and T-wave onset. Long-term ST database (LTST) verification demonstrated that the accuracy of STT detection reached above 91%. In addition, it had a good timeliness and robustness and was easy to implement. © 2011 World Scientific Publishing Company.

Liu D.,Zhejiang University | Lei L.,Zhejiang University | Yang B.,Zhejiang University | Yu Q.,Zhejiang University | And 2 more authors.
Bioresource Technology | Year: 2013

Pentachlorophenol (PCP) was dechlorinated by electrochemically active bacteria using an electrode as the direct electron donor. Dechlorination efficiency and coulombic efficiency (CE) were investigated. When hydrogen evolution reaction was eliminated by controlling the potential, both dechlorination efficiency and CE increase as the potential decreases, which implied the dechlorination was stimulated by electric current rather than hydrogen gas. Further investigation of the cyclic voltammetry characterization of the medium revealed nearly no redox mediator secreted by the bacteria. Moreover, the comparison of dechlorination experiments carried out with filtered and unfiltered medium provided convincible evidence that the dominating electron transfer mechanism for the dechlorination is direct electron transfer. Additionally, 454 pyrosequencing technique was employed to gain a comprehensive understanding of the biocathodic microbial community. The results showed Proteobacteria, Bacteroidetes and Firmicutes were the three predominant groups. This paper demonstrated the direct electron transfer mechanism could be involved in PCP dechlorination with a biocathode. © 2013 Elsevier Ltd.

PubMed | 306th Hospital of Peoples Liberation Army, Astronaut Research and Training Center and Chinese People's Liberation Army
Type: Journal Article | Journal: Chinese medical journal | Year: 2017

Few studies have focused on peripheral nerve conduction during exposure to microgravity. The -6 head-down tilt (HDT) comprises an experimental model used to simulate the space flight environment. This study investigated nerve conduction characteristics of rhesus monkeys before and after prolonged exposure to HDT.Six rhesus monkeys (3-4 years old) were tilted backward 6 from the horizontal. Nerve conduction studies (NCSs) were performed on the median, ulnar, tibial, and fibular motor nerves. Analysis of variance with a randomized block design was conducted to compare the differences in the NCS before and 7, 21, and 42 days after the -6 HDT.The proximal amplitude of the CMAP of the median nerve was significantly decreased at 21 and 42 days of HDT compared with the amplitude before HDT (4.38 2.83 vs. 8.40 2.66 mV, F = 4.85, P = 0.013 and 3.30 2.70 vs. 8.40 2.66 mV, F = 5.93, P = 0.004, respectively). The distal amplitude of the CMAP of the median nerve was significantly decreased at 7, 21, and 42 days of HDT compared with the amplitude before HDT (7.28 1.27 vs. 10.25 3.40 mV, F = 4.03, P = 0.039; 5.05 2.01 vs. 10.25 3.40 mV, F = 6.25, P = 0.04; and 3.95 2.79 vs. 10.25 3.40 mV, F = 7.35, P = 0.01; respectively). The proximal amplitude of the CMAP of the tibial nerve was significantly decreased at 42 days of HDT compared with the amplitude before HDT (6.14 1.94 vs. 11.87 3.19 mV, F = 5.02, P = 0.039).This study demonstrates that the compound muscle action potential amplitudes of nerves are decreased under simulated microgravity in rhesus monkeys. Moreover, rhesus monkeys exposed to HDT might be served as an experimental model for the study of NCS under microgravity.

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