检索结果-南通市图书馆

Study on cellular internalization of poly(vinyldiaminotriazine)-based hydrogen bonding type non-viral transgene vector

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2008年第15期53卷 2307-2314页

作者： YE GuiXiang cao ZhiQiang lin lin CHEN DaYong LIU WenGuang School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin 300072 China

Previously we successfully prepared poly(vinyldiaminotriazine)(PVDT)-based non-viral vectors which complexed plasmid DNA via hydrogen bonding with adenine-thymine base pairs. In this report, surface charges and complex sizes of this system were further examined. The results showed that PVDT-based polymer could cover surface charges of DNA resulting in slightly negative or neutral complexes. It was also found that the complex sizes were governed by two events: the aggregation induced by the insta-bility of neutral particles, and more compact complexes produced by PVDT-based polymers. In the study of cellular uptake, chlorpromazine and filipin Ⅲ were used to inhibit clathrin- and caveolae-me- diated endocytosis, respectively. We found that PVDT-based systems were transported into cells via a non-clathrin, non-caveolae mediated endocytosis. This special process was studied by temperature inhibition and kinetics assays. It was revealed that such a pathway was characterized by (i) a more en-ergy dependent process and (ii) a much slow transfection-effective internalization.

关键词：聚乙烯络合物氢键细胞提取

The Analytic Eigenvalue Structure of the 1+1 Dirac Oscillator

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2020年第9期37卷 10-14页

作者： Bo-Xing cao Fu-lin Zhang Department of Physics School of ScienceTianjin UniversityTianjin 300072China

We study the analytic structure for the eigenvalues of the one-dimensional Dirac oscillator,by analytically continning its frequency on the complex plane.A twofold Riemann surface is found,connecting the two states of a pair of particle and *** can,at least in principle,accomplish the transition from a positive energy state to its antiparticle state by moving the frequency continuously on the complex plane,without changing the Hamiltonian after *** result provides a visual explanation for the absence of a negative energy state with the quantum number n=0.

关键词： transition. Dirac connecting

The essential rate of approximation for radial function manifold

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2011年第9期54卷 1985-1994页

作者： lin ShaoBo cao FeiLong XU ZongBeni Institute for Information and System Sciences Xi'an Jiaotong University Xi'an 710049 China Institute of Metrology and Computational Sciences China Jiliang University Hangzhou 310018 China

In this paper, we investigate the radial function manifolds generated by a linear combination of radial functions. Let Wp^r（B^d） be the usual Sobolev class of functions on the unit ball 54. We study the deviation from the radial function manifolds to WP^r（b^d）. Our results show that the upper and lower bounds of approximation by a linear combination of radial functions are asymptotically identical. We also find that the radial function manifolds and ridge function manifolds generated by a linear combination of ridge functions possess the same rate of approximation.

关键词： radial function rate of approximation Sobolev class ridge function

Hepatitis B virus X protein-mediated upregulation of miR-221 activates the CXCL12-CXCR4 axis to promote NKT cells in HBVrelated hepatocellular carcinoma

在线全文

学校读者我要写书评

暂无评论

BIOCELL 2023年第7期47卷 1537-1548页

作者： YUE cao lin HU YISHU TANG Department of Laboratory Medicine The First Affiliated Hospital of Chongqing Medical UniversityChongqing400016China

Both hepatitis B virus X protein(HBx)and microRNA-221(miR-221)have been implicated in the development of hepatitis B virus(HBV)-related hepatocellular carcinoma(HCC).The present study demonstrates that HBx promotes HCC cell proliferation via the C-X-C motif chemokine ligand 12-C-X-C chemokine receptor type 4(CXCL12-CXCR4)*** predict that HBx/miR-221-mediated CXCL12/CXCR4 signaling induces NKT cells to promote HBV-related ***:After miR-221 mimic,miR-221 mimic negative control,miR-221 inhibitor,miR-221 inhibitor negative control were transfected into cells,the expression of CXCL12 and miR-221 was detected by qPCR and western *** we constructed a stable HBV-HCC cell ***-HCC cells were injected into the nude mice,thus a HBV-HCC mouse model was constructed.Q-PCR and western blot were used to detect the expression of HBx,miR-221,CXCL12 and CXCR4 in tumor *** expression of CXCL12 was detected by immunohistochemistry,and the expression of CXCR4,CD3 and CD56 was detected by *** levels of CXCL12,IL-2 and TNF-αin serum of mice were detected by ***-one patients with HBV-related HCC,61 patients with HBV-related cirrhosis,61 patients with chronic hepatitis B(CHB)and 30 healthy people were ***12,cytokine levels,and clinicopathological parameters were ***:Hepatitis B virus X protein upregulates the expression of miR-221 and CXCL12 in lentivirus(LV5)-HBx-transfected HepG2 *** protein promotes HepG2 cell proliferation in *** protein promoted tumor growth via the miR-221/CXCL12/CXCR4 pathway in a mouse tumor *** protein upregulated natural killer T cell expression via the CXCR4/CXCL12 pathway to promote tumor *** data demonstrated a positive correlation between CXCL12 concentration with Cre levels and Child-Pugh ***12 had an inferior diagnostic efficiency compared to IL-2 and IL-6 for HBV-related ***:We present evidence that HBx/miR-221-mediated CXCL12/CXCR4 sign

关键词： Hepatitis B virus X protein miR-221 Hepatocellular carcinoma CXCL12 NKT

Novel algorithm for detection and identification of radioactive materials in an urban environment

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2023年第10期34卷 103-116页

作者： Hao-lin Liu Hai-Bo Ji Jiang-Mei Zhang Jing Lu cao-lin Zhang Xing-Hua Feng Department of Automation University of Science and Technology of ChinaHefei 230026China School of Information Engineering Southwest University of Science and TechnologyMianyang 621010China Fundamental Science on Nuclear Wastes and Environment Safety Laboratory Southwest University of Science and TechnologyMianyang 621010China School of Automation and Information Engineering Sichuan University of Science and EngineeringZigong 643000China

This study introduces a novel algorithm to detect and identify radioactive materials in urban settings using time-series detector response data. To address the challenges posed by varying backgrounds and to enhance the quality and reliability of the energy spectrum data, we devised a temporal energy window. This partitioned the time-series detector response data, resulting in energy spectra that emphasize the vital information pertaining to radioactive materials. We then extracted characteristic features of these energy spectra, relying on the formation mechanism and measurement principles of the gammaray instrument spectrum. These features encompassed aggregated counts, peak-to-flat ratios, and peak-to-peak ratios. This methodology not only simplified the interpretation of the energy spectra's physical significance but also eliminated the necessity for peak searching and individual peak analyses. Given the requirements of imbalanced multi-classification, we created a detection and identification model using a weighted k-nearest neighbors(KNN) framework. This model recognized that energy spectra of identical radioactive materials exhibit minimal inter-class similarity. Consequently, it considerably boosted the classification accuracy of minority classes, enhancing the classifier's overall efficacy. We also executed a series of comparative experiments. Established methods for radionuclide identification classification, such as standard KNN, support vector machine, Bayesian network, and random tree, were used for comparison purposes. Our proposed algorithm realized an F1 measure of 0.9868 on the time-series detector response data, reflecting a minimum enhancement of 0.3% in comparison with other techniques. The results conclusively show that our algorithm outperforms others when applied to time-series detector response data in urban contexts.

关键词： Gamma-ray spectral analysis Nuclide identification Urban environment Temporal energy window Peakratio spectrum analysis Weighted KNN

A novel approach for feature extraction from a gamma‑ray energy spectrum based on image descriptor transferring for radionuclide identification

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2022年第12期33卷 88-104页

作者： Hao‑lin Liu Hai‑Bo Ji Jiang‑Mei Zhang cao‑lin Zhang Jing Lu Xing‑Hua Feng Department of Automation University of Science and Technology of ChinaHefei 230026China School of Information Engineering Southwest University of Science and TechnologyMianyang 621010China Fundamental Science on Nuclear Wastes and Environment Safety Laboratory Southwest University of Science and TechnologyMianyang 621010China

This study proposes a novel feature extraction approach for radionuclide identification to increase the precision of identification of the gamma-ray energy spectrum *** easier utilization of the information contained in the spectra,the vectors of the gamma-ray energy spectra from Euclidean space,which are fingerprints of the different types of radionuclides,were mapped to matrices in the Banach ***,to make the spectra in matrix form easier to apply to image-based deep learning frameworks,the matrices of the gamma-ray energy spectra were mapped to images in the RGB color space.A deep convolutional neural network(DCNN)model was constructed and trained on the ImageNet *** mapped gamma-ray energy spectrum images were applied as inputs to the DCNN model,and the corresponding outputs of the convolution layers and fully connected layers were transferred as descriptors of the images to construct a new classification model for radionuclide *** transferred image descriptors consist of global and local features,where the activation vectors of fully connected layers are global features,and activations from convolution layers are local features.A series of comparative experiments between the transferred image descriptors,peak information,features extracted by the histogram of the oriented gradients(HOG),and scale-invariant feature transform(SIFT)using both synthetic and measured data were applied to 11 classical *** results demonstrate that although the gamma-ray energy spectrum images are completely unfamiliar to the DCNN model and have not been used in the pre-training process,the transferred image descriptors achieved good classification *** global features have strong semantic information,which achieves an average accuracy of 92.76%and 94.86%on the synthetic dataset and measured dataset,*** results of the statistical comparison of features demonstrate that the proposed approach outperforms the peak-se

关键词： Radionuclide identification Feature extraction Transfer learning Gamma energy spectrum analysis Image descriptor

3D MXene architectures as sulfur hosts for high-performance lithium-sulfur batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2022年第3期31卷 429-439,I0012页

作者： Yu-Hong Liu cao-Yu Wang Si-lin Yang Fei-Fei cao Huan Ye College of Science Huazhong Agricultural UniversityWuhan 430070HubeiChina

Lithium-sulfur batteries(LSBs)are one of the most promising energy storage devices because of their high theoretical energy density;however,inherent issues including poor electrical conductivity and severe dissolution of S and its discharged products hinder their practical *** have metallic conductivity,ultra-thin two-dimensional(2D)structures,rich surface functional groups,and macrostructural adjustability and have been widely used to design advanced sulfur hosts.3D network structures assembled by 2D MXene nanosheets have shown superior performance for improving reaction kinetics,accommodating and dispersing sulfur at the micro-/nanoscale,and capturing polysulfides due to their porous interconnected ***,the applications of MXene architectures related to 2D layered structures,3D multilayered structures,and 3D spherical structures as sulfur hosts are *** structure-performance relationship,challenges for current designs,and opportunities for future 3D architectures for LSBs are also analyzed.

关键词： Lithium-sulfur batteries Cathodes Sulfur hosts MXenes 3D architectures

Direct Electrochemistry of Cytochrome c at a Hierarchically Nanostructured TiO_(2) Quantum Electrode

在线全文

学校读者我要写书评

暂无评论

Nano Research 2010年第5期3卷 369-378页

作者： Li Liu Ning Wang Xia cao lin Guo School of Chemistry and Environment Beijing University of Aeronautics and AstronauticsBeijing 100191China School of Material Science and Engineering Jiangsu University of Science and TechnologyJiangsu 212003China

Monodisperse TiO2 nanoparticles and urchin-like hierarchical TiO2 nanospheres assembled with ultrathin quantum nanowires(about 2 nm)have been synthesized by a simple template-free wet chemical *** morphology,structure,and crystallinity of the TiO2 nanomaterials were investigated by field emission scanning electron microscopy(FESEM),X-ray diffraction(XRD),and high resolution transmission electron microscopy(HRTEM).Electrochemical measurements with the hierarchically nanostructured TiO2 nanospheres as an electrode showed much better reversibility for direct electrochemistry of cytochrome c(cyt c)and much higher sensitivity than for an electrode composed of the monodisperse TiO2 *** excellent performance of the hierarchical TiO2 nanospheres may result from a quantum size effect,and their favorable nanostructure(with the presence of an abundance of both uniform macropores and mesopores),excellent structural stability and high specific surface *** relative ionic strength had significant effect on the direct *** high ionic strengths relative to cyt c concentration(I/c)induced a conformational change of cyt c on the nanostructure-coated electrode,from the native state to a partially unfolded one in 25 mmol/L phosphate buffer solution(pH 6.8).

关键词： Hierarchically nanostructured TiO2 cytochrome c ionic strength bioelectrochemistry

EXPERIMENTAL STUDY OF ENHANCED HEAT TRANSFER BY FLOW-INDUCED VIBRATION OF ELASTIC TUBE BUNDLES

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2000年第3期12卷 103-109页

作者： Tian, Maocheng Cheng, Fei Cheng, lin cao, Bingyang Shandong Univ of Technology Jinan China

New concept of heat transfer enhancement by flow-induced vibration was put forward, and a novel heat transfer element called elastic tube bundles was designed. The experimental investigation was performed on its characteristics of flow-induced vibration in out-tube or in-tube flow. Under the conditions of fixed heat flux and steam-water heat transfer, the regularity of heat transfer enhancement by flow-induced vibration was examined.

关键词： Flow of water Fluid structure interaction Heat exchangers Heat transfer Vibrations (mechanical)