| 1 | Generating dense and super-resolution ISAR image by combining bandwidth extrapolation and compressive sensing显示文摘Recent developing compressive sensing (CS) theory indicates that it is possible to obtain precise recovery of a sparse signal from very limited measurements,which provides a new way for data acquisition and signal processing as nature signals usually involve some degree of sparsity.In this paper,we present an algorithm for inversed synthetic aperture radar (ISAR) imaging with super resolution by combining CS and bandwidth extrapolation (BWE) technique.For ISAR imaging,the backscattering field of target is usually contributed by a few strong scattering centers,whose number is much less than that of image pixels.Thus,CS is intuitively suitable for constructing super resolution ISAR image.According to CS theory,the number of extracted dominating scatterers relies on the signal length,which indicates that if only limited data is available,it is difficult to generate dense ISAR image robustly by CS,and some signal components tend to lose.To soften this constraint,BWE is combined with CS imaging to increase the degree of freedom of signal while preserving its coherence.A refined CS-based formation for ISAR image-resolution enhancement is then developed.Both real and simulated data experiments are performed to evaluate the proposed approach,and an example of using this technique demonstrates the enhanced image resolution in application of maneuvering target imaging. | QUAN YingHui ZHANG Lei GUO Rui XING MengDao BAO Zheng | 2011 | Science China(Information Sciences)2011，54，10： | 15 |
| 3 | Influence of moderate hypothermia on cerebral oxygenation in pigs with intracranial hypertension显示文摘BACKGROUND: Moderate hypothermia is one of the effective therapeutic methods for head injury in recent years, there are many mechanisms of moderate hypothermia for brain protection, and its influence on cerebral oxygenation is also one of them. OBJECTIVE: To observe the influence of moderate hypothermia on cerebral oxygenation of animals with acute intracranial hypertension, and further investigate the protective mechanism of moderate hypothermia. DESIGN: A randomized controlled trial. SETTING: Department of Neurosurgery, Renji Hospital affiliated to the Medical College of Shanghai Jiao Tong University. MATERIALS: Twenty healthy little pigs, either male or female, weighing 4.5–5.5 kg, were used. Neurotrend-typed multiparameter monitoring system (Diametrics Company, British); CMA/100 micro-injection pump (Carnegie Company, Sweden). METHODS: The experiment was conducted in the Changzheng Hospital affiliated to the Second Military Medical University of Chinese PLA in November, 2001. The pigs were randomized into two groups: the normothermia group (control group, n =10) and moderate hypothermia group (n =10). ① Bilateral femoral arteries were separated, one was connected to pressometer for monitoring mean arterial pressure (MEP), and the other for analysis of blood gases [including peripheral blood pH value, arterial partial pressure of carbon dioxide (PaCO2), arterial partial pressure of carbon dioxide (PaCO2), HCO3–]. ② Rectal temperature was monitored with mercurial thermometer. ③ Intracranial pressure was monitored using Camino optic ICP probe placed in the subdural space. ④ Neurotrend multiparameter monitoring sensor was inserted into the white matter for about 4 cm to determine cerebral perfusion pressure (CPP, CPP=MAP(ICP), brain tissue partial oxygen pressure (PO2), partial pressure of carbon dioxide (PCO2), HCO3– and brain temperature. The rectal temperature of animals in the moderate hypothermia group was lowered to 34 ℃ using ice bags, and the body temperature was maintained at 33–35 ℃ for 2 hours. The changes of the parameters were observed continuously, and the pigs in the normothermia group were not treated with cooling. MAIN OUTCOME MEASURES: ① MAP, ICP, rectal temperature, CCP; Indexes of cerebral oxygenation detected with Neurotrend-typed multiparameter monitoring system; ② Results of blood gases analysis in the moderate hypothermia group. RESULTS: All the 20 pigs were involved in the analysis of results. ① MAP, ICP, rectal temperature, CCP and indexes of cerebral oxygenation: In the moderate hypothermia group, the ICP after cooling was obviously lower than that before cooling [(3.31±1.19), (5.33±0.95) kPa, P < 0.05], CCP was higher, brain tissue PCO2 [(12.03±1.73), (10.59±2.01) kPa, P < 0.05], and brain tissue pH value was higher [(7.03± 1.63), (9.40±1.30) kPa, P < 0.05], whereas the brain temperature was decreased as compared with that before cooling [(34.9±0.3), (37.2±0.2) ℃, P < 0.05]. ② Results of blood gases analysis in the moderate hypothermia group: There were no significant differences in the parameters of peripheral arterial blood gases analysis before and after cooling in the moderate hypothermia group (P > 0.05) CONCLUSION: Moderate hypothermia will not impair the cerebral oxygenation, and it can reduce brain tissue CO2 and decrease brain tissue acidosis. | Yinghui Bao Yumin Liang Jiyao Jiang Qizhong Luo Yicheng Lu | 2007 | Neural Regeneration Research2007，2，5： | 0 |
| 4 | Cooperative coordination-mediated multi-component self-assembly of“all-in-one”nanospike theranostic nano-platform for MRI-guided synergistic therapy against breast cancer显示文摘Carrier-free multi-component self-assembled nano-systems have attracted widespread attention owing to their easy preparation,high drug-loading efficiency,and excellent therapeutic efficacy.Herein,MnAs-ICG nanospike was generated by self-assembly of indocyanine green(ICG),manganese ions(Mn^(2+)),and arsenate(AsO_(4)^(3−))based on electrostatic and coordination interactions,effectively integrating the bimodal imaging ability of magnetic resonance imaging(MRI)and fluorescence(FL)imaging-guided synergistic therapy of photothermal/chemo/chemodynamic therapy within an“all-in-one”theranostic nano-platform.The as-prepared MnAs-ICG nanospike had a uniform size,well-defined nanospike morphology,and impressive loading capacities.The MnAs-ICG nanospike exhibited sensitive responsiveness to the acidic tumor microenvironment with morphological transformation and dimensional variability,enabling deep penetration into tumor tissue and on-demand release of functional therapeutic components.In vitro and in vivo results revealed that MnAs-ICG nanospike showed synergistic tumor-killing effect,prolonged blood circulation and increased tumor accumulation compared to their individual components,effectively resulting in synergistic therapy of photothermal/chemo/chemodynamic therapy with excellent anti-tumor effect.Taken together,this new strategy might hold great promise for rationally engineering multifunctional theranostic nano-platforms for breast cancer treatment. | Xiaojie Chen Xudong Fan Yue Zhang Yinghui Wei Hangsheng Zheng Dandan Bao Hengwu Xu Ji-Gang Piao Fanzhu Li Hongyue Zheng | 2022 | Acta Pharmaceutica Sinica B2022，12，9： | 0 |
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