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121.
利用超强超短激光脉冲产生的高能质子束的库仑能量损失可以重建稠密等离子体的二维密度分布,使用同时迭代重建算法(SIRT算法)研究等离子体二维密度重建的影响因素.研究等离子体密度梯度、密度量级和质子束入射能量对重建误差的影响,分析质子束成像探测等离子体密度之前获得等离子体大概方位的重要性,通过数据拟合确定了能量噪声和重建误差之间的解析关系式. 相似文献
122.
123.
The present article reports the heat transfer characteristics of a vertical stainless steel foil of 0.15 mm thickness (SS304) by circular impinging jets of various fluids such as pure water, nano-fluids (Al2O3-water, ф = 0.15%, 0.6%), and aqueous high-alcohol surfactant (HAS, i.e., 2-ethyl-hexanol, 100–400 ppm) studied using an infrared thermal imaging camera (A655sc, FLIR System). The enhancement in the heat transfer rates for Al2O3-water nano-fluids with ф = 0.15%, ф = 0.60%, and aqueous surfactant solution (150ppm) is found to be 140%, 207%, and 117% higher compared to pure water results, respectively. The surface characteristics of the foil after jet impingement by various fluids are also studied using scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and surface wettability. 相似文献
124.
磁共振图像的重建、后处理及可视化是磁共振成像(MRI)系统的重要组成部分.本文开发了一个新的用于磁共振图像重建、后处理及可视化的开源框架YAP(Yet Another Pipeline),利用此框架可以方便地构建图像处理流水线.与现有的一些其他开源框架相比,本文开发的框架具有如下特点:(1)采用基于接口的设计,可使用基于接口的插件对流水线的功能进行扩展;(2)允许用户使用编写脚本的方式构建图像处理流水线,编辑与修改流水线都很方便;(3)支持带有分支结构的流水线,便于流水线的构建与调试.目前,该框架已经在商用系统中获得了应用. 相似文献
125.
Liang Chen Yu Fan Jieru Qiu Dr. Régis Laurent Jin Li Prof. Dr. Jérôme Bignon Prof. Dr. Serge Mignani Prof. Dr. Anne-Marie Caminade Prof. Dr. Xiangyang Shi Prof. Dr. Jean-Pierre Majoral 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(26):5903-5910
First-in-class CuII and AuIII metaled phosphorus dendrons were synthesized and showed significant antiproliferative activity against several aggressive breast cancer cell lines. The data suggest that the cytotoxicity increases with reducing length of the alkyl chains, whereas the replacement of CuII with AuIII considerably increases the antiproliferative activity of metaled phosphorus dendrons. Very interestingly, we found that the cell death pathway is related to the nature of the metal complexed by the plain dendrons. CuII metaled dendrons showed a potent caspase-independent cell death pathway, whereas AuIII metaled dendrons displayed a caspase-dependent apoptotic pathway. The complexation of plain dendrons with AuIII increased the cellular lethality versus dendrons with CuII and promoted the translocation of Bax into the mitochondria and the release of Cytochrome C (Cyto C). 相似文献
126.
Xingxing Ge Xicheng Liu Zhenzhen Tian Shujiao Chen Xinyu Liu Lihua Guo Peiwei Gong Baoping Ling Xiang‐Ai Yuan Zhe Liu 《应用有机金属化学》2019,33(11)
Four half‐sandwich rutheniumII (RuII) complexes with triphenylamine‐modifed dipyridine frameworks were synthesized and characterized. The cytotoxicity of target complexes toward A549 (lung cancer cells), HeLa (cervical cancer cells) and HepG2 (hepatoma cells) were obtained by the MTT assay, which were superior to cisplatin with the IC50 values changed from 2.4 ± 0.1 μM to 9.2 ± 2.7 μM. Meanwhile, complexes possess the ability of antimetastasis to cancer cells. RuII complexes could be transported by serum albumin, catalyze the conversion of NADH (the reduced state of nicotinamide‐adenine dinucleotide) to NAD+ and induce the accumulation of reactive oxygen species, which confirmed the antineoplastic mechanism of oxidation. RuII complexes could enter A549 cells followed by a non‐energy dependent cellular uptake mechanism, target lysosomes with the Pearson's colocalization coefficient of 0.75, lead to lysosomal damage, disturb the cell cycle (S phase), and eventually induce apoptosis. The results demonstrate that these RuII complexes are potential anticancer agents with dual functions, including metastasis inhibition and lysosomal damage. 相似文献
127.
Jesús Emmanuel Solís‐Prez Jos Francisco Gmez‐Aguilar Lizeth Torres Ricardo Fabricio Escobar‐Jimnez Juan Reyes‐Reyes 《Mathematical Methods in the Applied Sciences》2019,42(18):7335-7348
In this work, the design of spectral observers for signal reconstruction based on Kalman filters is performed and evaluated. The conformable derivative and the beta‐derivative were used to design the Kalman filters. Both derivatives satisfy the same formulas of the classical derivation, eg, the chain rule. The derivative order, the Ricatti equation parameters, and the observers tuning parameters were optimized using an optimization algorithm based on the bat's echolocation behavior (Bat algorithm). The simulation results showed the advantages of using the proposed observers for the signal reconstruction. 相似文献
128.
In this study, Fe3O4@TiO2 nanoparticles were synthesized as a new Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) hybrid imaging agent and radiolabeled with 89Zr. In addition, Fe3O4 nanoparticles were synthesized and radiolabeled with 89Zr. Df-Bz-NCS was used as bifunctional ligand. The nanoconjugates were characterized with transmission electron microscopy, scanning electron microscopy, and dynamic light scattering. Radiolabeling yields were 100%. Breast and prostate cancer cell affinities and cytotoxicity were determined using in vitro cell culture assays. The results demonstrated that Fe3O4@TiO2 nanoparticles are promising for PET/MR imaging. Finally, unlike Fe3O4 nanoparticles, Fe3O4@TiO2 nanoparticles showed a fluorescence spectrum at an excitation wavelength of 250 nm and an emission wavelength of 314 nm. Therefore, in addition to bearing the magnetic properties of Fe3O4 nanoparticles, Fe3O4@TiO2 nanoparticles display fluorescence emission. This provides them with photodynamic therapy potential. Therefore multimodal treatment was performed with the combination of PDT and RT by using human prostate cancer cell line (PC3). The development of 89Zr-Df-Bz-NCS-Fe3O4@TiO2 nanoparticles as a new multifunctional PET/MRI agent with photodynamic therapy and hyperthermia therapeutic ability would be very useful. 相似文献
129.
Dr. Jinghui Zhang Lei Gong Xiaoshuang Zhang Dr. Mengliang Zhu Chaorui Su Qing Ma Dr. Dongdong Qi Prof. Yongzhong Bian Prof. Hongwu Du Prof. Jianzhuang Jiang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(61):13842-13848
Two-photon excited fluorescent (TPEF) materials are highly desirable for bioimaging applications owing to their unique characteristics of deep-tissue penetration and high spatiotemporal resolution. Herein, by connecting one, two, or three electron-deficient zinc porphyrin units to an electron-rich triazatruxene core via ethynyl π-bridges, conjugated multipolar molecules TAT-(ZnP) n (n=1–3) were developed as TPEF materials for cell imaging. The three new dyes present high fluorescence quantum yields (0.40–0.47) and rationally improved two-photon absorption (TPA) properties. In particular, the peak TPA cross section of TAT-ZnP (436 GM) is significantly larger than that of the ZnP reference (59 GM). The δTPA values of TAT-(ZnP)2 and TAT-(ZnP)3 further increase to 1031 and up to 1496 GM, respectively, indicating the effect of incorporated ZnP units on the TPA properties. The substantial improvement of the TPEF properties is attributed to the formation of π-conjugated quadrapole/octupole molecules and the extension of D -π-A-D systems, which has been rationalized by density function theory (DFT) calculations. Moreover, all of the three new dyes display good biocompatibility and preferential targeting ability toward cytomembrane, thus can be superior candidates for TPEF imaging of living cells. Overall, this work demonstrated a promising strategy for the development of porphyrin-based TPEF materials by the construction and extension of D -π-A-D multipolar array. 相似文献
130.
Wei Zhang Lin Deng Guangchao Wang Xianrong Guo Qiujin Li Jianfei Zhang Niveen M. Khashab 《Particle & Particle Systems Characterization》2014,31(9):985-993
Multifunctional magnetic microcapsules (MMCs) for the combined cancer cells hyperthermia and chemotherapy in addition to MR imaging are successfully developed. A classical layer‐by‐layer technique of oppositely charged polyelectrolytes (poly(allylamine hydrochloride) (PAH) and poly(4‐styrene sulfonate sodium) (PSS)) is used as it affords great controllability over the preparation together with enhanced loading of the chemotherapeutic drug (doxorubicin, DOX) in the microcapsules. Superparamagnetic iron oxide (SPIOs) nanoparticles are layered in the system to afford MMC1 (one SPIOs layer) and MMC2 (two SPIOs layers). Most interestingly, MMC1 and MMC2 show efficient hyperthermia cell death and controlled DOX release although their magnetic saturation value falls below 2.5 emu g?1, which is lower than the 7–22 emu g?1 reported to be the minimum value needed for biomedical applications. Moreover, MMCs are pH responsive where a pH 5.5 (often reported for cancer cells) combined with hyperthermia increases DOX release predictably. Both systems prove viable when used as T2 contrast agents for MR imaging in HeLa cells with high biocompatibility. Thus, MMCs hold a great promise to be used commercially as a theranostic platform as they are controllably prepared, reproducibly enhanced, and serve as drug delivery, hyperthermia, and MRI contrast agents at the same time. 相似文献