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31.
Li J Zhao K Hong X Yuan H Ma L Li J Bai Y Li T 《Colloids and surfaces. B, Biointerfaces》2005,40(3-4):179-182
Colloidal semiconductor nanocrystals have attracted considerable attention as a novel biological luminescent label. The bioinorganic conjugates of luminescent CdTe nanocrystals and protein, including CdTe/BSA (bovine serum albumin) and CdTe/MAB (mouse monoclonal antibody against hepatities B surface antigen), were formed via electrostatic/coordination self-assembly. Pure CdTe nanocrystals, CdTe/BSA and CdTe/MAB were used in the immunochromatographic assay experiments, respectively. And the results indicated that CdTe nanocrystals could be used and developed as a novel label with good stability, high sensitivity and facile determination of several analytes in immunochromatographic assay strips. 相似文献
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Huynh MH Meyer TJ Hiskey MA Jameson DL 《Journal of the American Chemical Society》2004,126(11):3608-3615
Reactions between the Os(VI)-nitrido salts (e.g., trans-[Os(VI)(tpy)(Cl)(2)(N)]PF(6) (tpy = 2,2':6',2"-terpyridine), cis-[Os(VI)(tpy)(Cl)(2)(N)]PF(6), and fac-[Os(VI)(tpm)(Cl)(2)(N)]PF(6) (tpm = tris(pyrazol-1-yl)methane)) and the hydroxylamines (e.g., H(2)NOH and MeHNOH) and the methoxylamines (e.g., H(2)NOMe and MeHNOMe) in dry MeOH at room temperature give three different types of products. They are Os(II)-dinitrogen (e.g., trans-, cis-, or fac-[Os(II)-N(2)]), Os(II)-nitrosyl [Os(II)-NO](+) (e.g., trans- or cis-[Os(II)-NO](+)), Os(IV)-hydroxyhydrazido (e.g., cis-[Os(IV)-N(H)N(Me)(OH)](+)), and Os(IV)-methoxyhydrazido (e.g., trans-/cis-[Os(IV)-N(H)N(H)(OMe)](+), and trans-/cis-[Os(IV)-N(H)N(Me)(OMe)](+)) adducts. The products depend in a subtle way on the electron content of the starting nitrido complexes, the nature of the hydroxylamines, the nature of the methoxylamines, and the reaction conditions. Their appearance can be rationalized by invoking the formation of a series of related Os(IV) adducts which are stable or decompose to give the final products by two different pathways. The first involves internal 2-electron transfer and extrusion of H(2)O, MeOH, or MeOMe to give [Os(II)-N(2)]. The second which gives [Os(II)-NO](+) appears to involve seven-coordinate Os(IV) intermediates based on the results of an (15)N-labeling study. 相似文献
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Jian Zhang Zhao‐Ji Li Yi‐Hang Wen Yao Kang Jian‐Kai Cheng Yuan‐Gen Yao 《无机化学与普通化学杂志》2004,630(15):2731-2735
Two new metal succinates modified by rigid bipyridines, Cd(4, 4′‐bpy)(C4H4O4)·1/4H2O ( 1 ) and Cu(2, 2′‐bpy)(C4H4O4)0.5(NO3)(H2O) ( 2 ) (bpy = bipyridine), have been synthesized by hydrothermal reactions and structurally determined. Complex 1 crystallizes in the orthorhombic space group Cmca with the cell parameters a = 11.696(2), b = 15.554(2), c = 15.874(3) Å, α = β = γ = 90.00°, V = 2888(3) Å3, Z = 8. Complex 2 crystallizes in the triclinic space group with a = 7.077(1), b = 9.838(2), c = 10.461(2) Å, α = 71.941(3)°, β = 73.078(3)°, γ = 74.502(3)°, V = 649.8(2) Å3, Z = 2. In complex 1 , a 2‐D network was formed by Cd‐succinato bonding. The 2‐D networks are pillared by 4, 4′‐bpy ligands, forming a 3‐D grid framework. The 2‐fold interpenetration of the resulting 3‐D frameworks completes the molecular structure. In complex 2 , the CuII atom adopts a distorted octahedral in which the CuII atoms are bridged by two H2O molecules into an infinite zigzag chain, [Cu2(H2O)2(C4H4O4)]n. The neighboring chains are further linked by π‐π stacking interactions into a 2‐D network, and the interlayer hydrogen bonds lead to the final 3‐D crystal structure. 相似文献
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In recent decades, emotion recognition has received considerable attention. As more enthusiasm has shifted to the physiological pattern, a wide range of elaborate physiological emotion data features come up and are combined with various classifying models to detect one’s emotional states. To circumvent the labor of artificially designing features, we propose to acquire affective and robust representations automatically through the Stacked Denoising Autoencoder (SDA) architecture with unsupervised pre-training, followed by supervised fine-tuning. In this paper, we compare the performances of different features and models through three binary classification tasks based on the Valence-Arousal-Dominance (VAD) affection model. Decision fusion and feature fusion of electroencephalogram (EEG) and peripheral signals are performed on hand-engineered features; data-level fusion is performed on deep-learning methods. It turns out that the fusion data perform better than the two modalities. To take advantage of deep-learning algorithms, we augment the original data and feed it directly into our training model. We use two deep architectures and another generative stacked semi-supervised architecture as references for comparison to test the method’s practical effects. The results reveal that our scheme slightly outperforms the other three deep feature extractors and surpasses the state-of-the-art of hand-engineered features. 相似文献
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利用选择液相外延的方法制备GaAs微尖阵列,通过扫描电子显微镜对微尖形貌进行了表征,并对此微尖阵列进行了场发射性能测试。结果表明,选择液相外延法制备的GaAs微尖呈金字塔状,两对面夹角为71°;微尖高度由生长窗口的尺寸决定,对底边为60μm的微尖,其高度约为42μm。此微尖阵列排列规则,具有场发射特性,开启电场约为5.1V/μm。发射电流稳定,当电场由8.0V/μm增加到11.9V/μm,发射电流由6μA增到74μA,在发射时间超过3h的情况下,电流波动不超过3%。另外,GaAs微尖阵列场发射的F-N曲线不为直线,分析表明是表面态和场渗透共同作用的结果。这对GaAs微尖阵列在场发射阴极方面的进一步研究具有重要的意义。 相似文献
39.
X射线衍射增强成像中的定量测量 总被引:1,自引:1,他引:0
提出了一种基于X射线衍射增强成像(DEI)断层计算机X射线层析术(CT)图像的物体尺寸精确测量方法.X射线衍射增强成像是一种基于相位衬度的成像技术.通过建立DEI的简化模型,研究衍射成像过程中品体转角、投影图像谷点位置、成像系统等效模糊等因素之间关系,由此具体探讨了系统模糊效应对圆物体边界成像带来的位置偏移,并以圆形被测样品为例.提出可精确测定直径的简单有效算法.通过理论仿真模型数据和北京同步辐射装置上的实测数据验证了该算法的精度.该方法实现了利用DEI图像对被测物体几何尺寸的精确测量,可用于对牛物组织样品等物体内部微小结构的尺寸的精确测量. 相似文献
40.
Liangcong Hu Xudong Xie Hang Xue Tiantian Wang Adriana C. Panayi Ze Lin Yuan Xiong Faqi Cao Chengcheng Yan Lang Chen Peng Cheng Kangkang Zha Yun Sun Guodong Liu Chenyan Yu Yiqiang Hu Ranyang Tao Wu Zhou Bobin Mi Guohui Liu 《Experimental & molecular medicine》2022,54(7):961
MicroRNAs (miRNAs) broadly regulate normal biological functions of bone and the progression of fracture healing and osteoporosis. Recently, it has been reported that miR-1224-5p in fracture plasma is a potential therapy for osteogenesis. To investigate the roles of miR-1224-5p and the Rap1 signaling pathway in fracture healing and osteoporosis development and progression, we used BMMs, BMSCs, and skull osteoblast precursor cells for in vitro osteogenesis and osteoclastogenesis studies. Osteoblastogenesis and osteoclastogenesis were detected by ALP, ARS, and TRAP staining and bone slice resorption pit assays. The miR-1224-5p target gene was assessed by siRNA-mediated target gene knockdown and luciferase reporter assays. To explore the Rap1 pathway, we performed high-throughput sequencing, western blotting, RT-PCR, chromatin immunoprecipitation assays and immunohistochemical staining. In vivo, bone healing was judged by the cortical femoral defect, cranial bone defect and femoral fracture models. Progression of osteoporosis was evaluated by an ovariectomy model and an aged osteoporosis model. We discovered that the expression of miR-1224-5p was positively correlated with fracture healing progression. Moreover, in vitro, overexpression of miR-1224-5p slowed Rankl-induced osteoclast differentiation and promoted osteoblast differentiation via the Rap1-signaling pathway by targeting ADCY2. In addition, in vivo overexpression of miR-1224-5p significantly promoted fracture healing and ameliorated the progression of osteoporosis caused by estrogen deficiency or aging. Furthermore, knockdown of miRNA-1224-5p inhibited bone regeneration in mice and accelerated the progression of osteoporosis in elderly mice. Taken together, these results identify miR-1224-5p as a key bone osteogenic regulator, which may be a potential therapeutic target for osteoporosis and fracture nonunion.Subject terms: Translational research, Cell signalling 相似文献